column_label: Evidence location type: table; table/location label: Table 4. Substrate profile of C. diversus beta-lactamases (PMC1135165 scanned page 889); row label: Form I | Benzylpenicillin; explicit primary cells: {'captured_segment': 'Table 4 Form I row Benzylpenicillin: Km cell 69 +/- 10 uM; kcat cell 570 +/- 30 s^-1; kcat/Km cell (8.3 +/- 0.8) x 10^6 M^-1 s^-1.', 'column_label': 'kcat (s^-1)', 'condition_label': 'Form I beta-lactamase of Citrobacter diversus ULA-27, the chromatofocusing form with pI 6.8; Table 4 substrate profile; the experiments were performed at 30 C in 25 mM-sodium phosphate, pH 7.2, containing 0.2 M-NaCl and bovine serum albumin (0.05 mg/ml).', 'metric': 'kcat', 'normalized_unit': 's^-1', 'normalized_value': 570.0, 'primary_cell': True, 'raw_unit': 's^-1', 'raw_value': '570 +/- 30', 'row_label': 'Form I | Benzylpenicillin', 'table_label': 'Table 4. Substrate profile of C. diversus beta-lactamases (PMC1135165 scanned page 889)'}; {'captured_segment': 'Table 4 Form I row Benzylpenicillin: Km cell 69 +/- 10 uM; kcat cell 570 +/- 30 s^-1; kcat/Km cell (8.3 +/- 0.8) x 10^6 M^-1 s^-1.', 'column_label': 'Km (uM)', 'condition_label': 'Form I beta-lactamase of Citrobacter diversus ULA-27, the chromatofocusing form with pI 6.8; Table 4 substrate profile; the experiments were performed at 30 C in 25 mM-sodium phosphate, pH 7.2, containing 0.2 M-NaCl and bovine serum albumin (0.05 mg/ml).', 'metric': 'Km', 'normalized_unit': 'mM', 'normalized_value': 0.069, 'primary_cell': True, 'raw_unit': 'uM', 'raw_value': '69 +/- 10', 'row_label': 'Form I | Benzylpenicillin', 'table_label': 'Table 4. Substrate profile of C. diversus beta-lactamases (PMC1135165 scanned page 889)'}; kcat/Km raw value: (8.3 +/- 0.8) x 10^6; raw unit: M^-1 s^-1; normalized value: 8300 s^-1 mM^-1; assay condition: Form I beta-lactamase of Citrobacter diversus ULA-27, the chromatofocusing form with pI 6.8; Table 4 substrate profile; the experiments were performed at 30 C in 25 mM-sodium phosphate, pH 7.2, containing 0.2 M-NaCl and bovine serum albumin (0.05 mg/ml).; captured primary segment: Table 4 Form I row Benzylpenicillin: Km cell 69 +/- 10 uM; kcat cell 570 +/- 30 s^-1; kcat/Km cell (8.3 +/- 0.8) x 10^6 M^-1 s^-1.

normalized_value_unit_evidence: kcat raw 570 +/- 30 s^-1 -> 570.0 s^-1; Km raw 69 +/- 10 uM -> 0.069 mM; explicit printed kcat/Km raw (8.3 +/- 0.8) x 10^6 M^-1 s^-1 -> 8300 s^-1 mM^-1. Conversion: 8.3 x 10^6 M^-1 s^-1 x 0.001 M/mM = 8300 s^-1 mM^-1. The normalized ratio is taken directly from the printed primary cell, not recomputed from kcat and Km.

raw_value_unit_evidence: Table 4, Form I block, row Benzylpenicillin: Km cell 69 +/- 10 uM; kcat cell 570 +/- 30 s^-1. Explicit printed kcat/Km primary cell: (8.3 +/- 0.8) x 10^6 M^-1 s^-1.

row_label: Form I | Benzylpenicillin


enzyme_display_name: beta-lactamase

organism: Citrobacter diversus

substrate_name: Oxacillin

source_db: oed

verification_status: corrected

ki_display: Not reported

mutation_signature: Unknown

protein_accession_database: UniProt

source_license: CC BY 4.0

km_unit: mM

sequence_source: UniProtKB:P22390 reviewed entry retrieved 2026-05-27

sequence_variant_note: Sequence is treated as wild-type because the source explicitly marked the record as wild-type.

column_label: Table 4 (scanned journal page 889), Form I block, substrate row `Oxacillin`: Km (uM) = 230; kcat (s^-1) = 206; kcat/Km (M^-1 s^-1) = 0.9 x 10^6.

normalized_value_unit_evidence: kcat: printed cell 206 s^-1 -> 206.0 s^(-1) (the unit is already s^-1); the exported value is 206.0 s^(-1). Km: printed cell 230 uM -> 0.23 mM (divide by 1000); the exported value is 0.3 mM. kcat/Km: the paper PRINTS the kcat/Km cell 0.9 x 10^6 M^-1 s^-1 for this row -> 900.0 s^(-1)*mM^(-1) (divide by 1000 for M^-1 to mM^-1); the exported value is 686.6666666666667 s^(-1)*mM^(-1).

row_label: Table 4 Form I, decoded plain-numeral transcription, substrate row `Oxacillin`

table_label: Table 4 (scanned journal page 889) 'Substrate profile of C. diversus beta-lactamases'

data_origin: experimental

enzyme: beta-lactamase

substrate: Oxacillin

status: corrected

source: oed


substrate_name: Cefuroxime

column_label: Table 4 (scanned journal page 889), Form I block, substrate row `Cefuroxime`: Km (uM) = 70; kcat (s^-1) = 54; kcat/Km (M^-1 s^-1) = 0.77 x 10^6.

normalized_value_unit_evidence: kcat: printed cell 54 s^-1 -> 54.0 s^(-1) (the unit is already s^-1); the exported value is 54.0 s^(-1). Km: printed cell 70 uM -> 0.07 mM (divide by 1000); the exported value is 0.072 mM. kcat/Km: the paper PRINTS the kcat/Km cell 0.77 x 10^6 M^-1 s^-1 for this row -> 770.0 s^(-1)*mM^(-1) (divide by 1000 for M^-1 to mM^-1); the exported value is 750.0 s^(-1)*mM^(-1).

row_label: Table 4 Form I, decoded plain-numeral transcription, substrate row `Cefuroxime`

substrate: Cefuroxime


substrate_name: Methicillin

kcat_over_km_origin: calculated

substrate: Methicillin


organism: Bacillus cereus

substrate_name: cefotaxime

sequence_variant_note: Resolved canonical sequence from UniProtKB:P04190 direct REST lookup; D120 substitution reconstructed by curation review and applied mutation signature D120S to reconstruct the assayed variant sequence.

mutation_type: substitution

substrate: cefotaxime


substrate_name: Imipenem

sequence_variant_note: Resolved canonical sequence from UniProtKB:P04190 direct REST lookup; D120 substitution reconstructed by curation review and applied mutation signature D120E to reconstruct the assayed variant sequence.

substrate: Imipenem


sequence_variant_note: Resolved canonical sequence from UniProtKB:P04190 direct REST lookup; D120 substitution reconstructed by curation review and applied mutation signature D120Q to reconstruct the assayed variant sequence.


substrate_name: Nitrocefin

sequence_source: UniProtKB:P04190 direct REST lookup; D120 substitution reconstructed by curation review

substrate: Nitrocefin


substrate_name: Penicillin G

substrate: Penicillin G


organism: Enterobacter cloacae

substrate_name: Cephaloridine

verification_status: unverified

sequence_source: canonical UniProtKB P05364 precursor sequence

substrate: Cephaloridine

status: unverified


substrate_name: cefepime

substrate: cefepime


substrate_name: Cephalosporin C

sequence_variant_note: Resolved canonical sequence from UniProtKB P05364 precursor sequence with N346A applied in mature-chain numbering; UniProt signal peptide is residues 1-20, so mature residue 346 maps to precursor residue 366 and applied mutation signature N346A with inferred residue-numbering offset +15 to reconstruct the assayed variant sequence.

substrate: Cephalosporin C


substrate_name: Ceftazidime

sequence_source: UniProtKB P05364 precursor sequence with L293C applied in mature-chain numbering; UniProt signal peptide is residues 1-20, so mature residue 293 maps to precursor residue 313

sequence_variant_note: Resolved sequence already matches the mutant residue(s) after applying an inferred residue-numbering offset +20, so it is treated as a source-provided variant sequence.

substrate: Ceftazidime


sequence_variant_note: Resolved canonical sequence from UniProtKB P05364 precursor sequence with N346I applied in mature-chain numbering; UniProt signal peptide is residues 1-20, so mature residue 346 maps to precursor residue 366 and applied mutation signature N346I with inferred residue-numbering offset +15 to reconstruct the assayed variant sequence.


sequence_variant_note: Resolved canonical sequence from UniProtKB:P05364 canonical sequence with reconstructed substitution using +20 signal-peptide offset and applied mutation signature Y221G with inferred residue-numbering offset +20 to reconstruct the assayed variant sequence.


sequence_source: UniProtKB:P05364 canonical sequence with reconstructed substitution using +20 signal-peptide offset


sequence_variant_note: Resolved canonical sequence from UniProtKB:P05364 canonical sequence with reconstructed substitution using +20 signal-peptide offset and applied mutation signature L293C with inferred residue-numbering offset +20 to reconstruct the assayed variant sequence.


verification_status: verified

sequence_source: UniProtKB:P05364 canonical sequence

column_label: Table 1; row depsipeptide 3; columns kcat (s^-1), Km (uM), kcat/Km (s^-1 M^-1); Scheme 1 maps compound 3 to the expected aminothiazolyl methoxyiminoacetylglycyl oxybenzoic acid

raw_value_unit_evidence: Table 1: depsipeptide 3 kcat 19 +/- 2 s^-1; Km 59 +/- 15 uM; kcat/Km 3.3 x 10^5 s^-1 M^-1

row_label: depsipeptide 3

table_label: Table 1

status: verified


organism: Bacteroides fragilis

substrate_name: Cefixime

sequence_source: UniProtKB:P25910 reviewed entry BLAB_BACFG; direct REST lookup 2026-05-27

assay_conditions_summary: pH 7.2; 298.15 K; buffer 50 uM phosphate

column_label: Table 1; row Cefixime; column kcat (s^-1) raw value 22; column Km (uM) raw value 53 uM; column relative kcat/Km raw value 8.6 (relative, not absolute; absolute kcat/Km derived by division).

normalized_value_unit_evidence: kcat 22 s^-1 = 22 s^-1. Km 53 uM = 53/1000 = 0.053 mM. kcat/Km is not printed as an absolute value in the paper, so paper kcat/Km = paper_kcat / paper_km = 22 / 0.053 = 415.09433962264154 s^-1 mM^-1.

raw_value_unit_evidence: Table 1 (page 1156), row Cefixime: kcat column 22 s^-1; Km column 53 uM; relative kcat/Km column 8.6. The table prints only a relative kcat/Km; no absolute kcat/Km value is printed.

row_label: Cefixime

table_label: Table 1. Kinetic parameters of beta-lactam antibiotics with CcrA Metallo-beta-lactamase

substrate: Cefixime


substrate_name: ceftriaxone

substrate: ceftriaxone


substrate_name: mecillinam

column_label: Literal Table 1 Mecillinam row on official PMC page 1156: kcat 14, Km 180 uM, and relative kcat/Km 1.6; page 1155 fixes pH 7.2 and 25 C.

normalized_value_unit_evidence: kcat=14 s^-1; Km=0.18 mM; current absolute same-row quotient=77.77777777777779 s^-1 mM^-1. Relative kcat/Km 1.6 is retained separately and is not an absolute efficiency.

raw_value_unit_evidence: Table 1 Mecillinam row: kcat 14 s^-1; Km 180 uM; relative kcat/Km 1.6.

row_label: Mecillinam

substrate: mecillinam


substrate_name: azlocillin

column_label: TABLE 1. Kinetic parameters of B-lactam antibiotics with CcrA Metallo-B-lactamase; substrate row 'Azlocillin'; column 'kcat (s^-1)' = 120; column 'Relative kcat' = 62; column 'Km (uM)' = 83; column 'Relative kcat/Km' = 30. Printed line: Azlocillin | 120 | 62 | 83 | 30

normalized_value_unit_evidence: Km: printed cell 83 uM; 83 uM / 1000 = 0.083 mM. kcat: printed cell 120 s^-1, already the catalog unit s^(-1) (no min^-1/60 step applies anywhere in this paper). kcat/Km: Table 1 prints no absolute ratio; the exact quotient of this row's own printed cells is 120 s^-1 / 0.083 mM = 1445.7831325301204 s^(-1)*mM^(-1). The printed fifth column reads 30 and is a dimensionless percentage against benzylpenicillin = 100.

raw_value_unit_evidence: Table 1 (printed page 1156), row 'Azlocillin': kcat = 120 s^-1; Km = 83 uM; Relative kcat/Km = 30 (dimensionless, benzylpenicillin = 100). Printed line: Azlocillin | 120 | 62 | 83 | 30

row_label: Table 1, substrate row 'Azlocillin'

substrate: azlocillin


column_label: TABLE 1. Kinetic parameters of B-lactam antibiotics with CcrA Metallo-B-lactamase; substrate row 'Cefepime'; column 'kcat (s^-1)' = 58; column 'Relative kcat' = 30; column 'Km (uM)' = 27; column 'Relative kcat/Km' = 45. Printed line: Cefepime | 58 | 30 | 27 | 45

normalized_value_unit_evidence: Km: printed cell 27 uM; 27 uM / 1000 = 0.027 mM. kcat: printed cell 58 s^-1, already the catalog unit s^(-1) (no min^-1/60 step applies anywhere in this paper). kcat/Km: Table 1 prints no absolute ratio; the exact quotient of this row's own printed cells is 58 s^-1 / 0.027 mM = 2148.1481481481483 s^(-1)*mM^(-1). The printed fifth column reads 45 and is a dimensionless percentage against benzylpenicillin = 100.

raw_value_unit_evidence: Table 1 (printed page 1156), row 'Cefepime': kcat = 58 s^-1; Km = 27 uM; Relative kcat/Km = 45 (dimensionless, benzylpenicillin = 100). Printed line: Cefepime | 58 | 30 | 27 | 45

row_label: Table 1, substrate row 'Cefepime'


substrate_name: Cefoperazone

column_label: Literal Table 1 Cefoperazone row on official PMC page 1156: kcat 76, Km 26 uM, and relative kcat/Km 60; page 1155 fixes pH 7.2 and 25 C.

normalized_value_unit_evidence: kcat=76 s^-1; Km=0.026 mM; current absolute same-row quotient=2923.0769230769233 s^-1 mM^-1. Relative kcat/Km 60 is retained separately and is not an absolute efficiency.

raw_value_unit_evidence: Table 1 Cefoperazone row: kcat 76 s^-1; Km 26 uM; relative kcat/Km 60.

row_label: Cefoperazone

substrate: Cefoperazone


substrate_name: Cephalothin

column_label: Literal Table 1 Cephalothin row on official PMC page 1156: kcat 29, Km 3.3 uM, and relative kcat/Km 180; the printed Km rounds to current three-decimal 0.003 mM. Page 1155 fixes pH 7.2 and 25 C.

normalized_value_unit_evidence: The printed Km is 0.0033 mM and rounds to current stored 0.003 mM; kcat=29 s^-1; current stored-component quotient=9666.666666666666 s^-1 mM^-1. The unrounded source-cell quotient is 8787.878787878788; relative kcat/Km 180 is separate.

raw_value_unit_evidence: Table 1 Cephalothin row: kcat 29 s^-1; Km 3.3 uM; relative kcat/Km 180.

row_label: Cephalothin

substrate: Cephalothin


substrate_name: Mezlocillin sodium

column_label: Literal Table 1 Mezlocillin row on official PMC page 1156: kcat 85, Km 110 uM, and relative kcat/Km 16; page 1155 fixes pH 7.2 and 25 C. Current Mezlocillin sodium is source-bound to this row.

normalized_value_unit_evidence: kcat=85 s^-1; Km=0.11 mM; current absolute same-row quotient=772.7272727272727 s^-1 mM^-1. Relative kcat/Km 16 is retained separately and is not an absolute efficiency.

raw_value_unit_evidence: Table 1 Mezlocillin row: kcat 85 s^-1; Km 110 uM; relative kcat/Km 16.

row_label: Mezlocillin

substrate: Mezlocillin sodium


sequence_source: UniProtKB:P05364 direct accession lookup

column_label: cefotaxime row; kcat, Km, and kcat/Km columns

row_label: cefotaxime


substrate_name: 3-[(Phenylacetyl)glycyl]oxybenzoic acid

column_label: Table 1; row depsipeptide 7; columns kcat (s^-1), Km (uM), kcat/Km (s^-1 M^-1); compound-numbering page maps compound 7 to 3-[[N-(Phenylacetyl)glycyl]oxy]benzoic acid

raw_value_unit_evidence: Table 1: depsipeptide 7 kcat 125 s^-1; Km 230 uM; kcat/Km 5.4 x 10^5 s^-1 M^-1

row_label: depsipeptide 7

substrate: 3-[(Phenylacetyl)glycyl]oxybenzoic acid


column_label: Table 1 (Steady State Parameters for Turnover of Retro-Substrates), substrate row 11, enzyme block P99; column 'kcat (S-1)' = 0.25±0.02; column 'Km (uM)' = 32±7; column 'kcat/Km (s-1M-1)' = 7.9x103. The three P99 columns are the first three numeric columns after the substrate label of that row.

normalized_value_unit_evidence: kcat: printed Table 1 cell 0.25 under the column head kcat (S-1); the printed unit is already canonical, so kcat = 0.25 s^(-1). Km: printed Table 1 cell 32 under the column head Km (uM); 1 uM is 0.001 mM, so 32 / 1000 = 0.032 mM. kcat/Km: printed Table 1 cell 7.9 x 10^3 under the column head kcat/Km (s-1M-1); 1 M^-1 s^-1 is 0.001 s^-1 mM^-1, so 7.9 x 10^3 / 1000 = 7.9 s^-1 mM^-1.

raw_value_unit_evidence: Table 1, substrate row 11, P99 enzyme block: printed kcat cell 0.25±0.02 under the column head kcat (S-1); printed Km cell 32±7 under the column head Km (uM); printed kcat/Km cell 7.9x103 under the column head kcat/Km (s-1M-1), which decodes to 7.9 x 10^3 M^-1 s^-1.

table_label: Table 1: Steady State Parameters for Turnover of Retro-Substrates (Bioorg Med Chem 2010, 18(1):282)


column_label: Table 1 (Steady State Parameters for Turnover of Retro-Substrates), substrate row 10, enzyme block P99; column 'kcat (S-1)' = 0.33±0.03; column 'Km (uM)' = 700±140; column 'kcat/Km (s-1M-1)' = 4.7x102. The three P99 columns are the first three numeric columns after the substrate label of that row.

normalized_value_unit_evidence: kcat: printed Table 1 cell 0.33 under the column head kcat (S-1); the printed unit is already canonical, so kcat = 0.33 s^(-1). Km: printed Table 1 cell 700 under the column head Km (uM); 1 uM is 0.001 mM, so 700 / 1000 = 0.7 mM. kcat/Km: printed Table 1 cell 4.7 x 10^2 under the column head kcat/Km (s-1M-1); 1 M^-1 s^-1 is 0.001 s^-1 mM^-1, so 4.7 x 10^2 / 1000 = 0.47 s^-1 mM^-1.

raw_value_unit_evidence: Table 1, substrate row 10, P99 enzyme block: printed kcat cell 0.33±0.03 under the column head kcat (S-1); printed Km cell 700±140 under the column head Km (uM); printed kcat/Km cell 4.7x102 under the column head kcat/Km (s-1M-1), which decodes to 4.7 x 10^2 M^-1 s^-1.


substrate_name: Ticarcillin

sequence_source: UniProtKB:P52663 FASTA retrieved from rest.uniprot.org

substrate: Ticarcillin


substrate_name: moxalactam

substrate: moxalactam


substrate_name: cefotaxime

substrate: cefotaxime


substrate_name: cefoxitin

substrate: cefoxitin


substrate_name: cefotetan

substrate: cefotetan


substrate_name: Meropenem

substrate: Meropenem


organism: Escherichia coli

substrate_name: Ampicillin

kcat_over_km_display: Not reported

sequence_variant_note: Mutation context is present, but no sequence was resolved for this record.

substrate: Ampicillin


sequence_source: UniProtKB reviewed accession P62593 direct REST/FASTA lookup on 2026-05-27

column_label: Table II (PDF page 4 of 9, journal page 23055), substrate block `Cefotaxime`, b-lactamase sub-row `TEMpUC19`: kcat (s^-1) = 0.18; Km (uM) = 230; kcat/Km (M^-1 s^-1) = 7.8 x 10^2.

normalized_value_unit_evidence: kcat: printed cell 0.18 s^-1 is already the export unit -> 0.18 s^(-1); the exported value is 202.0 s^(-1). Km: printed cell 230 uM -> 0.23 mM (divide by 1000); the exported value is 0.1 mM. kcat/Km: the paper PRINTS the kcat/Km cell 7.8 x 10^2 M^-1 s^-1 for this Table II row -> 0.78 s^(-1)*mM^(-1) (divide by 1000 for M^-1 to mM^-1); the exported value is 2020.0 s^(-1)*mM^(-1).

row_label: Table II, decoded plain-numeral transcription, substrate block `Cefotaxime`, b-lactamase sub-row `TEMpUC19`

table_label: Table II (PDF page 4 of 9, journal page 23055) 'Kinetics parameters of TEMpUC19 and mutant derivatives'


substrate_name: Cephaloridine

substrate: Cephaloridine


substrate_name: Cephalosporin C

substrate: Cephalosporin C


substrate_name: amoxicillin

substrate: amoxicillin


substrate_name: aztreonam

substrate: aztreonam


substrate_name: Ceftazidime

substrate: Ceftazidime


substrate_name: Cefuroxime

substrate: Cefuroxime


enzyme_display_name: Beta-lactamase TEM

substrate_name: piperacillin

sequence_source: UniProtKB:P62593 canonical sequence preserved as context; row-specific mutant sequence not reconstructed

sequence_variant_note: Canonical sequence is preserved, but mutation context is present; variant sequence was not attached without safely applying the mutation.

enzyme: Beta-lactamase TEM

substrate: piperacillin


substrate_name: Penicillin G

sequence_source: UniProtKB:P62593 direct REST/FASTA check on 2026-05-27

substrate: Penicillin G


column_label: Table II (PDF page 4 of 9, journal page 23055), substrate block `Cephaloridine`, b-lactamase sub-row `TEMpUC19`: kcat (s^-1) = 780; Km (uM) = 670; kcat/Km (M^-1 s^-1) = 1.2 x 10^6.

normalized_value_unit_evidence: kcat: printed cell 780 s^-1 is already the export unit -> 780.0 s^(-1); the exported value is 947.0 s^(-1). Km: printed cell 670 uM -> 0.67 mM (divide by 1000); the exported value is 0.67 mM. kcat/Km: the paper PRINTS the kcat/Km cell 1.2 x 10^6 M^-1 s^-1 for this Table II row -> 1200.0 s^(-1)*mM^(-1) (divide by 1000 for M^-1 to mM^-1); the exported value is 1413.4328358208954 s^(-1)*mM^(-1).

row_label: Table II, decoded plain-numeral transcription, substrate block `Cephaloridine`, b-lactamase sub-row `TEMpUC19`


substrate_name: Cephalothin

substrate: Cephalothin


sequence_source: UniProtKB:P62593 REST FASTA/JSON accessed 2026-05-27; PMID:10438473 for mutation context

column_label: table label: TABLE II Kinetics parameters of TEMpUC19 and mutant derivatives; row label: Cephalosporin C / TEMpUC19; column label: the kcat and Km cells of this one TABLE II line only: the TEMpUC19 (parental) line of the Cephalosporin C substrate block. No cell is taken from any other line of the same substrate block, from any other substrate block, or from any other table of this paper.; raw value: kcat 33 s^-1, Km 950 uM, printed kcat/Km (3.5 6 0.4) 3 104 M^-1 s^-1; raw unit: s^-1 for kcat, uM for Km, M^-1 s^-1 for the printed kcat/Km column; normalized value: kcat 33.0 s^-1, Km 0.95 mM, kcat/Km 34.73684210526316 s^-1 mM^-1; normalized unit: s^-1, mM, s^-1 mM^-1; condition label: Kinetics Measurements: kinetics measurements were carried out by continuous spectrophotometric assays at room temperature in a Hewlett-Packard 452 diode-array instrument; the values of kcat and Km were determined from the Lineweaver-Burk plots of the initial steady-state velocities for each enzyme. The enzyme is the parental TEMpUC19 beta-lactamase purified from E. coli JM83 transformants. Exported assay conditions: pH 7.0, 295.15 K.

normalized_value_unit_evidence: kcat 33 s^-1 is already in the export's unit and is stored as 33.0 s^-1; exported kcat 33.0 s^-1. Km 950 uM divided by 1000 gives 0.95 mM at the export's stored precision; exported Km 0.95 mM. kcat/Km is recorded as the quotient of this same row's own two cells as stored, 33.0 s^-1 divided by 0.95 mM giving 34.73684210526316 s^-1 mM^-1, and of nothing else; exported kcat/Km 34.73684210526316 s^-1 mM^-1.

raw_value_unit_evidence: TABLE II, Cephalosporin C substrate block, TEMpUC19 (parental) line: kcat 33 s^-1; Km 950 uM; printed kcat/Km (3.5 6 0.4) 3 104 M^-1 s^-1.

row_label: Cephalosporin C / TEMpUC19


sequence_variant_note: Resolved canonical sequence from uniprot_rest_accession:P62593 and applied mutation signature R164S with inferred residue-numbering offset -2 to reconstruct the assayed variant sequence.

assay_conditions_summary: pH 7; 295.15 K; buffer full are run in 100 mM sodium phosphate

column_label: Table II (Kinetics parameters of TEMpUC19 and mutant derivatives), substrate block 'Ampicillin', b-lactamase row 'R164S'; column 'kcat (s^-1)' = 15; column 'Km (uM)' = 37; column 'kcat/Km (M^-1 s^-1)' = 4.2 x 10^5.

normalized_value_unit_evidence: kcat: printed Table II cell 15 in a column headed kcat (s^-1); s^-1 is already the canonical unit, so no unit conversion applies and the value is 15 s^(-1). Km: printed Table II cell 37 in a column headed Km (uM); 1 uM is 1/1000 mM, so 37 / 1000 = 0.037 mM. kcat/Km: printed Table II cell 4.2 x 10^5 in a column headed kcat/Km (M^-1 s^-1), that is 420000 s^(-1)*M^(-1); 1 M^(-1) is 1/1000 mM^(-1), so 420000 / 1000 = 420 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table II, substrate block Ampicillin, b-lactamase row R164S: kcat = 15 s^-1; Km = 37 uM; printed kcat/Km = 4.2 x 10^5 M^-1 s^-1. The number printed after the plus-or-minus glyph beside each cell is the fit error and is not an exported metric.

table_label: Table II: Kinetics parameters of TEMpUC19 and mutant derivatives (J. Biol. Chem. 1999, 274(33):23052-23060). Printed column heads: Substrate; b-Lactamase; kcat (s^-1); Km (uM); kcat/Km (M^-1 s^-1)


sequence_variant_note: Resolved sequence already matches the mutant residue(s) after applying an inferred residue-numbering offset -2, so it is treated as a source-provided variant sequence.


sequence_variant_note: Resolved canonical sequence from uniprot_rest_accession:P62593 and applied mutation signature D179N with inferred residue-numbering offset -2 to reconstruct the assayed variant sequence.

column_label: Table II (Kinetics parameters of TEMpUC19 and mutant derivatives), substrate block 'Cephalothin', b-lactamase row 'D179N'; column 'kcat (s^-1)' = 0.21; column 'Km (uM)' = 48; column 'kcat/Km (M^-1 s^-1)' = 4.2 x 10^3.

normalized_value_unit_evidence: kcat: printed Table II cell 0.21 in a column headed kcat (s^-1); s^-1 is already the canonical unit, so no unit conversion applies and the value is 0.21 s^(-1). Km: printed Table II cell 48 in a column headed Km (uM); 1 uM is 1/1000 mM, so 48 / 1000 = 0.048 mM. kcat/Km: printed Table II cell 4.2 x 10^3 in a column headed kcat/Km (M^-1 s^-1), that is 4200 s^(-1)*M^(-1); 1 M^(-1) is 1/1000 mM^(-1), so 4200 / 1000 = 4.2 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table II, substrate block Cephalothin, b-lactamase row D179N: kcat = 0.21 s^-1; Km = 48 uM; printed kcat/Km = 4.2 x 10^3 M^-1 s^-1. The number printed after the plus-or-minus glyph beside each cell is the fit error and is not an exported metric.


sequence_variant_note: Resolved canonical sequence from UniProtKB:P62593 REST FASTA/JSON accessed 2026-05-27; PMID:10438473 for mutation context and applied mutation signature R164S with inferred residue-numbering offset -2 to reconstruct the assayed variant sequence.


sequence_source: UniProtKB P62593 canonical sequence with TEM-numbered mutation reconstructed by direct coordinate check


sequence_variant_note: Resolved canonical sequence from UniProtKB P62593 canonical sequence with TEM-numbered mutation reconstructed by direct coordinate check and applied mutation signature D179G with inferred residue-numbering offset -5 to reconstruct the assayed variant sequence.


column_label: Table II (Kinetics parameters of TEMpUC19 and mutant derivatives), substrate block 'Aztreonam', b-lactamase row 'D179N'; column 'kcat (s^-1)' = 0.06; column 'Km (uM)' = 220; column 'kcat/Km (M^-1 s^-1)' = 2.5 x 10^2.

normalized_value_unit_evidence: kcat: printed Table II cell 0.06 in a column headed kcat (s^-1); s^-1 is already the canonical unit, so no unit conversion applies and the value is 0.06 s^(-1). Km: printed Table II cell 220 in a column headed Km (uM); 1 uM is 1/1000 mM, so 220 / 1000 = 0.22 mM. kcat/Km: printed Table II cell 2.5 x 10^2 in a column headed kcat/Km (M^-1 s^-1), that is 250 s^(-1)*M^(-1); 1 M^(-1) is 1/1000 mM^(-1), so 250 / 1000 = 0.25 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table II, substrate block Aztreonam, b-lactamase row D179N: kcat = 0.06 s^-1; Km = 220 uM; printed kcat/Km = 2.5 x 10^2 M^-1 s^-1. The number printed after the plus-or-minus glyph beside each cell is the fit error and is not an exported metric.


substrate_name: ceftriaxone

sequence_variant_note: No sequence was resolved for this record, so variant-aware sequence handling could not be applied.

substrate: ceftriaxone


substrate_name: Ticarcillin

substrate: Ticarcillin


sequence_variant_note: Sequence is treated as wild-type because the source explicitly marked the record as wild-type.

assay_conditions_summary: pH 7; 303.15 K; buffer 50 mM phosphate

column_label: PMID 12962487 Table 4: Kinetic Parameters of Toho-1 against Various Antibiotics (Biochemistry 2003, 42, 10634-10643, journal page 10639); row 'cephalosporin (3) | cefotaxime'; columns 'kcat (s-1)', 'Km (uM)' and 'kcat/Km (uM-1 s-1)'; printed cells kcat = 250 s-1, Km = 120 uM, kcat/Km = 2.1 uM-1 s-1. The exported kcat and Km are the literal printed cells of that one row after Km uM-to-mM normalization; the exported kcat/Km is the quotient of those same two cells as stored. No value is taken from another row, another column, another cofactor condition, or another paper.

normalized_value_unit_evidence: metric: kcat; raw value: 250 s-1; raw unit: s^-1; normalized value: 250.0 s^(-1); metric: Km; raw value: 120 uM; raw unit: uM; normalized value: 0.12 mM; metric: kcat/Km; raw value: same-row quotient of the two printed cells; normalized value: 2083.3333333333335 s^-1 mM^-1; assay condition: Steady-state kinetic parameters for the wild-type Toho-1 class A extended-spectrum beta-lactamase; hydrolysis detected by monitoring the absorbance of beta-lactam solution in 50 mM phosphate buffer (pH 7.0), reaction in a total volume of 500 uL at 30 C (Uvikon 860 spectrophotometer). Wild-type enzyme, no mutation.

raw_value_unit_evidence: Table 4 row as printed: kcat = 250 s-1; Km = 120 uM; kcat/Km = 2.1 uM-1 s-1.

row_label: cephalosporin (3) | cefotaxime (Table 4)


substrate_name: Cefdinir

substrate: Cefdinir


sequence_source: UniProtKB Q47066 direct REST lookup; reviewed Swiss-Prot BLT1_ECOLX canonical sequence

column_label: PMID 12962487 Table 4: Kinetic Parameters of Toho-1 against Various Antibiotics (Biochemistry 2003, 42, 10634-10643, journal page 10639); row 'penicillin | benzylpenicillin'; columns 'kcat (s-1)', 'Km (uM)' and 'kcat/Km (uM-1 s-1)'; printed cells kcat = 68 s-1, Km = 23 uM, kcat/Km = 3.0 uM-1 s-1. The exported kcat and Km are the literal printed cells of that one row after Km uM-to-mM normalization; the exported kcat/Km is the quotient of those same two cells as stored. No value is taken from another row, another column, another cofactor condition, or another paper.

normalized_value_unit_evidence: metric: kcat; raw value: 68 s-1; raw unit: s^-1; normalized value: 68.0 s^(-1); metric: Km; raw value: 23 uM; raw unit: uM; normalized value: 0.023 mM; metric: kcat/Km; raw value: same-row quotient of the two printed cells; normalized value: 2956.521739130435 s^-1 mM^-1; assay condition: Steady-state kinetic parameters for the wild-type Toho-1 class A extended-spectrum beta-lactamase; hydrolysis detected by monitoring the absorbance of beta-lactam solution in 50 mM phosphate buffer (pH 7.0), reaction in a total volume of 500 uL at 30 C (Uvikon 860 spectrophotometer). Wild-type enzyme, no mutation.

raw_value_unit_evidence: Table 4 row as printed: kcat = 68 s-1; Km = 23 uM; kcat/Km = 3.0 uM-1 s-1.

row_label: penicillin | benzylpenicillin (Table 4)


column_label: PMID 12962487 Table 4: Kinetic Parameters of Toho-1 against Various Antibiotics (Biochemistry 2003, 42, 10634-10643, journal page 10639); row 'cephalosporin (1) | cephaloridine'; columns 'kcat (s-1)', 'Km (uM)' and 'kcat/Km (uM-1 s-1)'; printed cells kcat = 200 s-1, Km = 280 uM, kcat/Km = 0.7 uM-1 s-1. The exported kcat and Km are the literal printed cells of that one row after Km uM-to-mM normalization; the exported kcat/Km is the quotient of those same two cells as stored. No value is taken from another row, another column, another cofactor condition, or another paper.

normalized_value_unit_evidence: metric: kcat; raw value: 200 s-1; raw unit: s^-1; normalized value: 200.0 s^(-1); metric: Km; raw value: 280 uM; raw unit: uM; normalized value: 0.28 mM; metric: kcat/Km; raw value: same-row quotient of the two printed cells; normalized value: 714.2857142857142 s^-1 mM^-1; assay condition: Steady-state kinetic parameters for the wild-type Toho-1 class A extended-spectrum beta-lactamase; hydrolysis detected by monitoring the absorbance of beta-lactam solution in 50 mM phosphate buffer (pH 7.0), reaction in a total volume of 500 uL at 30 C (Uvikon 860 spectrophotometer). Wild-type enzyme, no mutation.

raw_value_unit_evidence: Table 4 row as printed: kcat = 200 s-1; Km = 280 uM; kcat/Km = 0.7 uM-1 s-1.

row_label: cephalosporin (1) | cephaloridine (Table 4)


substrate_name: Nitrocefin

column_label: PMID 12962487 Table 4: Kinetic Parameters of Toho-1 against Various Antibiotics (Biochemistry 2003, 42, 10634-10643, journal page 10639); row 'cephalosporin (1) | nitrocefin'; columns 'kcat (s-1)', 'Km (uM)' and 'kcat/Km (uM-1 s-1)'; printed cells kcat = 160 s-1, Km = 59 uM, kcat/Km = 2.7 uM-1 s-1. The exported kcat and Km are the literal printed cells of that one row after Km uM-to-mM normalization; the exported kcat/Km is the quotient of those same two cells as stored. No value is taken from another row, another column, another cofactor condition, or another paper.

normalized_value_unit_evidence: metric: kcat; raw value: 160 s-1; raw unit: s^-1; normalized value: 160.0 s^(-1); metric: Km; raw value: 59 uM; raw unit: uM; normalized value: 0.059 mM; metric: kcat/Km; raw value: same-row quotient of the two printed cells; normalized value: 2711.8644067796613 s^-1 mM^-1; assay condition: Steady-state kinetic parameters for the wild-type Toho-1 class A extended-spectrum beta-lactamase; hydrolysis detected by monitoring the absorbance of beta-lactam solution in 50 mM phosphate buffer (pH 7.0), reaction in a total volume of 500 uL at 30 C (Uvikon 860 spectrophotometer). Wild-type enzyme, no mutation.

raw_value_unit_evidence: Table 4 row as printed: kcat = 160 s-1; Km = 59 uM; kcat/Km = 2.7 uM-1 s-1.

row_label: cephalosporin (1) | nitrocefin (Table 4)

substrate: Nitrocefin


substrate_name: cefcapene

column_label: PMID 12962487 Table 4: Kinetic Parameters of Toho-1 against Various Antibiotics (Biochemistry 2003, 42, 10634-10643, journal page 10639); row 'cephalosporin (4) | cefcapene'; columns 'kcat (s-1)', 'Km (uM)' and 'kcat/Km (uM-1 s-1)'; printed cells kcat = 100 s-1, Km = 46 uM, kcat/Km = 2.2 uM-1 s-1. The exported kcat and Km are the literal printed cells of that one row after Km uM-to-mM normalization; the exported kcat/Km is the quotient of those same two cells as stored. No value is taken from another row, another column, another cofactor condition, or another paper.

normalized_value_unit_evidence: metric: kcat; raw value: 100 s-1; raw unit: s^-1; normalized value: 100.0 s^(-1); metric: Km; raw value: 46 uM; raw unit: uM; normalized value: 0.046 mM; metric: kcat/Km; raw value: same-row quotient of the two printed cells; normalized value: 2173.913043478261 s^-1 mM^-1; assay condition: Steady-state kinetic parameters for the wild-type Toho-1 class A extended-spectrum beta-lactamase; hydrolysis detected by monitoring the absorbance of beta-lactam solution in 50 mM phosphate buffer (pH 7.0), reaction in a total volume of 500 uL at 30 C (Uvikon 860 spectrophotometer). Wild-type enzyme, no mutation.

raw_value_unit_evidence: Table 4 row as printed: kcat = 100 s-1; Km = 46 uM; kcat/Km = 2.2 uM-1 s-1.

row_label: cephalosporin (4) | cefcapene (Table 4)

substrate: cefcapene


column_label: PMID 12962487 Table 4: Kinetic Parameters of Toho-1 against Various Antibiotics (Biochemistry 2003, 42, 10634-10643, journal page 10639); row 'cephalosporin (1) | cephalothin'; columns 'kcat (s-1)', 'Km (uM)' and 'kcat/Km (uM-1 s-1)'; printed cells kcat = 480 s-1, Km = 39 uM, kcat/Km = 12 uM-1 s-1. The exported kcat and Km are the literal printed cells of that one row after Km uM-to-mM normalization; the exported kcat/Km is the quotient of those same two cells as stored. No value is taken from another row, another column, another cofactor condition, or another paper.

normalized_value_unit_evidence: metric: kcat; raw value: 480 s-1; raw unit: s^-1; normalized value: 480.0 s^(-1); metric: Km; raw value: 39 uM; raw unit: uM; normalized value: 0.039 mM; metric: kcat/Km; raw value: same-row quotient of the two printed cells; normalized value: 12307.692307692309 s^-1 mM^-1; assay condition: Steady-state kinetic parameters for the wild-type Toho-1 class A extended-spectrum beta-lactamase; hydrolysis detected by monitoring the absorbance of beta-lactam solution in 50 mM phosphate buffer (pH 7.0), reaction in a total volume of 500 uL at 30 C (Uvikon 860 spectrophotometer). Wild-type enzyme, no mutation.

raw_value_unit_evidence: Table 4 row as printed: kcat = 480 s-1; Km = 39 uM; kcat/Km = 12 uM-1 s-1.

row_label: cephalosporin (1) | cephalothin (Table 4)


substrate_name: Sulbactam

column_label: Table 4; row label: sulbactam; column label: kcat (s^-1), Km (uM), kcat/Km (uM^-1 s^-1); raw value: 0.18, 0.31, and 0.58; raw unit: s^-1, uM, and uM^-1 s^-1; normalized value: 0.18 s^-1, 0.00031 mM, and 580 s^-1*mM^-1; assay condition: hydrolysis at 30 C in 50 mM phosphate buffer pH 7.0.

normalized_value_unit_evidence: kcat normalized_value=0.18 normalized_unit=s^(-1); Km normalized_value=0.00031 normalized_unit=mM; kcat/Km normalized_value=580 normalized_unit=s^(-1)*mM^(-1).

raw_value_unit_evidence: Table 4 sulbactam cells: kcat raw_value=0.18 raw_unit=s^-1; Km raw_value=0.31 raw_unit=uM; kcat/Km raw_value=0.58 raw_unit=uM^-1 s^-1.

row_label: sulbactam

table_label: Table 4. Kinetic Parameters of Toho-1 against Various Antibiotics

substrate: Sulbactam


sequence_source: UniProtKB:P62593 direct lookup on 2026-05-27

column_label: Table II (PDF page 4 of 9, journal page 23055), substrate block `Ceftazidime`, b-lactamase sub-row `TEMpUC19`: kcat (s^-1) = 0.008; Km (uM) = 200; kcat/Km (M^-1 s^-1) = 4.0 x 10^1.

normalized_value_unit_evidence: kcat: printed cell 0.008 s^-1 is already the export unit -> 0.008 s^(-1); the exported value is 18.0 s^(-1). Km: printed cell 200 uM -> 0.2 mM (divide by 1000); the exported value is 0.2 mM. kcat/Km: the paper PRINTS the kcat/Km cell 4.0 x 10^1 M^-1 s^-1 for this Table II row -> 0.04 s^(-1)*mM^(-1) (divide by 1000 for M^-1 to mM^-1); the exported value is 90.0 s^(-1)*mM^(-1).

row_label: Table II, decoded plain-numeral transcription, substrate block `Ceftazidime`, b-lactamase sub-row `TEMpUC19`


column_label: Table II (PDF page 4 of 9, journal page 23055), substrate block `Piperacillin`, b-lactamase sub-row `TEMpUC19`: kcat (s^-1) = 770; Km (uM) = 70; kcat/Km (M^-1 s^-1) = 1.1 x 10^7.

normalized_value_unit_evidence: kcat: printed cell 770 s^-1 is already the export unit -> 770.0 s^(-1); the exported value is 1275.0 s^(-1). Km: printed cell 70 uM -> 0.07 mM (divide by 1000); the exported value is 0.04 mM. kcat/Km: the paper PRINTS the kcat/Km cell 1.1 x 10^7 M^-1 s^-1 for this Table II row -> 11000.0 s^(-1)*mM^(-1) (divide by 1000 for M^-1 to mM^-1); the exported value is 31875.0 s^(-1)*mM^(-1).

row_label: Table II, decoded plain-numeral transcription, substrate block `Piperacillin`, b-lactamase sub-row `TEMpUC19`


substrate_name: cefotaxime

substrate: cefotaxime


substrate_name: Ampicillin

substrate: Ampicillin


substrate_name: Cephaloridine

substrate: Cephaloridine


sequence_source: UniProtKB:P62593 FASTA direct lookup; reviewed Swiss-Prot entry BLAT_ECOLX

column_label: Confirmed from Table II row Aztreonam / TEMpUC19; columns kcat, Km, and kcat/Km.

raw_value_unit_evidence: Table II Aztreonam TEMpUC19 row reports kcat 0.4 +/- 0.1 s^-1; Km 550 +/- 200 microM; kcat/Km (7.4 +/- 3.0) x 10^2 M^-1 s^-1.

row_label: Aztreonam / TEMpUC19

table_label: Table II. Kinetics parameters of TEMpUC19 and mutant derivatives


substrate_name: beta-Lactam

substrate: beta-Lactam


substrate_name: cefpirome; cephaloridine; ampicillin; cefoxitin; ceftazidime; cefotaxime; cefepime

source_db: brenda;skid

source_license: CC BY 4.0; CC BY-NC-ND 4.0

sequence_variant_note: Source notes indicate a mutant or variant enzyme, but no machine-applicable substitution signature was available.

proof_lines:
37 C, pH 7.0
Raw SKiD Env: Temp=37 C, pH=7

source_databases_merged: brenda skid

source: brenda;skid


substrate_name: Penicillin G; H2O / H2O; Cephalothin

source_license: SABIO-RK terms (free for academic use; see sabiork.h-its.org)

sequence_variant_note: Resolved canonical sequence from reconstructed_from_uniprot_accession and applied mutation signature Y105D with inferred residue-numbering offset -10 to reconstruct the assayed variant sequence.

proof_lines: SABIO-RK modifier species: beta-lactamase(Enzyme) mutant Y105D

substrate: Penicillin G; H2O / H2O; Cephalothin


sequence_variant_note: Resolved canonical sequence from reconstructed_from_uniprot_accession and applied mutation signature Y105G with inferred residue-numbering offset -10 to reconstruct the assayed variant sequence.


substrate_name: Penicillin G; H2O / Cephalothin; H2O

sequence_variant_note: Resolved canonical sequence from reconstructed_from_uniprot_accession and applied mutation signature Y105R with inferred residue-numbering offset -10 to reconstruct the assayed variant sequence.

proof_lines: SABIO-RK modifier species: beta-lactamase(Enzyme) mutant Y105R

substrate: Penicillin G; H2O / Cephalothin; H2O


substrate_name: aztreonam

assay_conditions_summary: pH 7; 310.15 K; buffer pH 7

column_label: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes; CTX-M-25 column block: kcat (s^-1) / Km (uM) / kcat per Km (uM^-1 s^-1); Aztreonam row

normalized_value_unit_evidence: kcat 84.0 s^-1; Km 0.12 mM; kcat_over_km 700.0 s^-1 mM^-1 as the quotient of the same TABLE 3 row and same CTX-M-25 column-block kcat and Km cells; the paper's own printed ratio cell reads 0.7 uM^-1 s^-1 = 700.0 s^-1 mM^-1

raw_value_unit_evidence: kcat 84 s^-1; Km 120 uM; printed kcat/Km 0.7 uM^-1 s^-1

row_label: Aztreonam row; CTX-M-25 column block (first three numeric cells)

substrate: aztreonam


column_label: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes; CTX-M-25 column block: kcat (s^-1) / Km (uM) / kcat per Km (uM^-1 s^-1); Cephalothin row

normalized_value_unit_evidence: kcat 230.0 s^-1; Km 0.19 mM; kcat_over_km 1210.5263157894738 s^-1 mM^-1 as the quotient of the same TABLE 3 row and same CTX-M-25 column-block kcat and Km cells; the paper's own printed ratio cell reads 1.2 uM^-1 s^-1 = 1200.0 s^-1 mM^-1

raw_value_unit_evidence: kcat 230 s^-1; Km 190 uM; printed kcat/Km 1.2 uM^-1 s^-1

row_label: Cephalothin row; CTX-M-25 column block (first three numeric cells)


substrate_name: piperacillin

column_label: Table 2. Kinetic parameters of CTX-M-14 against various substrates; row Piperacillin; column Km (uM) raw 20; column kcat (s^-1) raw 39; column kcat/Km (uM^-1 s^-1) raw 2.0.

normalized_value_unit_evidence: kcat=39.0 s^-1 (printed in s^-1, no conversion); Km=0.02 mM (20 uM divided by 1000); kcat/Km=1950.0 s^-1 mM^-1 (quotient of this record's own two printed cells, 39 s^-1 / 0.02 mM = 1950.0 s^-1 mM^-1).

raw_value_unit_evidence: Table 2 row Piperacillin: kcat 39 s^-1; Km 20 uM; the row-level transcription line is: | 2facc57377822923 | Piperacillin | piperacillin | 39 | 20 | 0.020 | 2.0 | 2000 | 1950 | confirmed; table-rounding compatible |

row_label: Piperacillin


column_label: Table 2. Kinetic parameters of CTX-M-14 against various substrates; row Cefaloridine; column Km (uM) raw 125; column kcat (s^-1) raw 1300; column kcat/Km (uM^-1 s^-1) raw 10.

normalized_value_unit_evidence: kcat=1300.0 s^-1 (printed in s^-1, no conversion); Km=0.125 mM (125 uM divided by 1000); kcat/Km=10400.0 s^-1 mM^-1 (quotient of this record's own two printed cells, 1300 s^-1 / 0.125 mM = 10400.0 s^-1 mM^-1).

raw_value_unit_evidence: Table 2 row Cefaloridine: kcat 1300 s^-1; Km 125 uM; the row-level transcription line is: | 66e1cc0be48fcc90 | Cefaloridine | Cephaloridine | 1300 | 125 | 0.125 | 10 | 10000 | 10400 | confirmed; alternate spelling and table-rounding compatible |

row_label: Cefaloridine


column_label: Table 2. Kinetic parameters of CTX-M-14 against various substrates; row Cefalothin; column Km (uM) raw 27; column kcat (s^-1) raw 510; column kcat/Km (uM^-1 s^-1) raw 19.

raw_value_unit_evidence: Table 2 row Cefalothin: kcat 510 s^-1; Km 27 uM; the row-level transcription line is: | 686edd1e15296263 | Cefalothin | Cephalothin | 510 | 27 | 0.027 | 19 | 19000 | 18888.88888888889 | confirmed; alternate spelling and table-rounding compatible |

row_label: Cefalothin


substrate_name: Imipenem

substrate: Imipenem


substrate_name: Cephalothin


substrate_name: Cefuroxime

sequence_source: UniProtKB:Q8KSA6 reviewed FASTA direct lookup

column_label: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes; CTX-M-25 column block: kcat (s^-1) / Km (uM) / kcat per Km (uM^-1 s^-1); Cefuroxime row

normalized_value_unit_evidence: kcat 190.0 s^-1; Km 0.044 mM; kcat_over_km 4318.181818181818 s^-1 mM^-1 as the quotient of the same TABLE 3 row and same CTX-M-25 column-block kcat and Km cells; the paper's own printed ratio cell reads 4.3 uM^-1 s^-1 = 4300.0 s^-1 mM^-1

raw_value_unit_evidence: kcat 190 s^-1; Km 44 uM; printed kcat/Km 4.3 uM^-1 s^-1

row_label: Cefuroxime row; CTX-M-25 column block (first three numeric cells)

substrate: Cefuroxime


substrate_name: Penicillin G

column_label: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes; CTX-M-25 column block: kcat (s^-1) / Km (uM) / kcat per Km (uM^-1 s^-1); Benzylpenicillin row

normalized_value_unit_evidence: kcat 33.0 s^-1; Km 0.074 mM; kcat_over_km 445.945945945946 s^-1 mM^-1 as the quotient of the same TABLE 3 row and same CTX-M-25 column-block kcat and Km cells; the paper's own printed ratio cell reads 0.4 uM^-1 s^-1 = 400.0 s^-1 mM^-1

raw_value_unit_evidence: kcat 33 s^-1; Km 74 uM; printed kcat/Km 0.4 uM^-1 s^-1

row_label: Benzylpenicillin row; CTX-M-25 column block (first three numeric cells)

substrate: Penicillin G


substrate_name: Ceftazidime

column_label: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes; CTX-M-25 column block: kcat (s^-1) / Km (uM) / kcat per Km (uM^-1 s^-1); Ceftazidime row

normalized_value_unit_evidence: kcat 33.0 s^-1; Km 0.013 mM; kcat_over_km 2538.4615384615386 s^-1 mM^-1 as the quotient of the same TABLE 3 row and same CTX-M-25 column-block kcat and Km cells; the paper's own printed ratio cell reads 2.6 uM^-1 s^-1 = 2600.0 s^-1 mM^-1

raw_value_unit_evidence: kcat 33 s^-1; Km 13 uM; printed kcat/Km 2.6 uM^-1 s^-1

row_label: Ceftazidime row; CTX-M-25 column block (first three numeric cells)

substrate: Ceftazidime


column_label: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes; CTX-M-25 column block: kcat (s^-1) / Km (uM) / kcat per Km (uM^-1 s^-1); Cefotaxime row

normalized_value_unit_evidence: kcat 101.0 s^-1; Km 0.028 mM; kcat_over_km 3607.142857142857 s^-1 mM^-1 as the quotient of the same TABLE 3 row and same CTX-M-25 column-block kcat and Km cells; the paper's own printed ratio cell reads 3.6 uM^-1 s^-1 = 3600.0 s^-1 mM^-1

raw_value_unit_evidence: kcat 101 s^-1; Km 28 uM; printed kcat/Km 3.6 uM^-1 s^-1

row_label: Cefotaxime row; CTX-M-25 column block (first three numeric cells)


sequence_source: UniProtKB:Q9L5C7 direct REST/FASTA check on 2026-05-27

column_label: Table 2. Kinetic parameters of CTX-M-14 against various substrates; row Cefcapene; column Km (uM) raw 25; column kcat (s^-1) raw 110; column kcat/Km (uM^-1 s^-1) raw 4.4.

normalized_value_unit_evidence: kcat=110.0 s^-1 (printed in s^-1, no conversion); Km=0.025 mM (25 uM divided by 1000); kcat/Km=4400.0 s^-1 mM^-1 (printed kcat/Km cell 4.4 uM^-1 s^-1 for this row, which normalizes to 4400.0 s^-1 mM^-1).

raw_value_unit_evidence: Table 2 row Cefcapene: kcat 110 s^-1; Km 25 uM; the row-level transcription line is: | 7ae4b1397ba3b1f5 | Cefcapene | cefcapene | 110 | 25 | 0.025 | 4.4 | 4400 | 4400 | confirmed |

row_label: Cefcapene


column_label: Table 2. Kinetic parameters of CTX-M-14 against various substrates; row Benzylpenicillin; column Km (uM) raw 11; column kcat (s^-1) raw 48; column kcat/Km (uM^-1 s^-1) raw 4.4.

normalized_value_unit_evidence: kcat=48.0 s^-1 (printed in s^-1, no conversion); Km=0.011 mM (11 uM divided by 1000); kcat/Km=4363.636363636364 s^-1 mM^-1 (quotient of this record's own two printed cells, 48 s^-1 / 0.011 mM = 4363.636363636364 s^-1 mM^-1).

raw_value_unit_evidence: Table 2 row Benzylpenicillin: kcat 48 s^-1; Km 11 uM; the row-level transcription line is: | 805658f5e37b0e67 | Benzylpenicillin | Penicillin G | 48 | 11 | 0.011 | 4.4 | 4400 | 4363.636363636364 | confirmed; synonym and table-rounding compatible |

row_label: Benzylpenicillin


column_label: Table 2. Kinetic parameters of CTX-M-14 against various substrates; row Cefotaxime; column Km (uM) raw 41; column kcat (s^-1) raw 1400; column kcat/Km (uM^-1 s^-1) raw 34.

raw_value_unit_evidence: Table 2 row Cefotaxime: kcat 1400 s^-1; Km 41 uM; the row-level transcription line is: | c57c5c7a1a08f6f0 | Cefotaxime | cefotaxime | 1400 | 41 | 0.041 | 34 | 34000 | 34146.34146341463 | confirmed; table-rounding compatible |

row_label: Cefotaxime


substrate_name: Meropenem

column_label: Table label: Table 2: Kinetic parameters of CTX-M-14 against various substrates. Row: Meropenem. Columns read: kcat (s^-1) cell 0.007, Km (uM) cell 0.11, kcat/Km (uM^-1 s^-1) cell 0.07. metric: kcat; raw value: 0.007; raw unit: s^-1; normalized value: 0.007 s^(-1); metric: Km; raw value: 0.11; raw unit: uM; normalized value: 0.00011 mM, stored by the export at four-decimal precision as 0.0001 mM; metric: kcat/Km; raw value: 0.07; raw unit: uM^-1 s^-1; normalized value: 70.0 s^-1 mM^-1; assay condition: Hydrolysis of beta-lactam antibiotics by CTX-M-14 was monitored by absorbance in 50 mM phosphate buffer at pH 7.0; reactions were 500 uL at 30 C, with BSA 20 ug/mL added to dilute beta-lactamase solutions. Export row conditions: pH 7; 303.15 K; buffer 50 mM phosphate.

normalized_value_unit_evidence: Table 2 row Meropenem: kcat 0.007 s^-1 = 0.007 s^(-1); Km 0.11 uM = 0.00011 mM (1 uM = 0.001 mM), which equals the export's stored value 0.0001 mM at the export's stored precision of four decimal places; kcat/Km printed 0.07 uM^-1 s^-1 x 1000 = 70.0 s^-1 mM^-1 (1 uM^-1 s^-1 = 1000 mM^-1 s^-1), decimal-matching the exported 70.0 and equal to the quotient of the exported cells 0.007 s^-1 / 0.0001 mM.; the columns Km uM, Km mM and the two kcat/Km columns hold the paper's printed value and its unit-normalized form side by side.

raw_value_unit_evidence: package Km rounded from table | | Table 2 cells for row Meropenem read in the paper's own units: kcat = 0.007 s^-1; Km = 0.11 uM; kcat/Km = 0.07 uM^-1 s^-1

row_label: Meropenem

substrate: Meropenem


substrate_name: Cefdinir


substrate_name: Doripenem

substrate: Doripenem


substrate_name: Nitrocefin

sequence_source: UniProtKB:Q9L5C7 direct REST lookup on 2026-05-27


substrate_name: cefalotin

substrate: cefalotin


substrate_name: ampicillin

substrate: ampicillin


substrate_name: ceftazidime

substrate: ceftazidime


substrate_name: meropenem

substrate: meropenem


substrate_name: doripenem

substrate: doripenem


substrate_name: cefoxitin

substrate: cefoxitin


substrate_name: nitrocefin

substrate: nitrocefin


sequence_source: UniProtKB:P62593 direct REST lookup


substrate_name: carbenicillin

substrate: carbenicillin


substrate_name: Ampicillin

substrate: Ampicillin


substrate_name: Cephaloridine

substrate: Cephaloridine


substrate_name: Substituted beta-amino acid; H2O; Penicillin G; Cephaloridine; H2O; Cephalothin; H2O; Cefotaxime

proof_lines: SABIO-RK modifier species: beta-lactamase(Enzyme) mutant W165S:A237T:E240C


substrate_name: Ampicillin; H2O; Penicillin G; Cephaloridine; Cephalothin; Cefotaxime

proof_lines: SABIO-RK modifier species: beta-lactamase(Enzyme) mutant W165S


substrate_name: Cephalothin

substrate: Cephalothin


substrate_name: Penicillin G


source_db: skid

source_license: CC BY-NC-ND 4.0

sequence_source: UniProtKB:P28585 FASTA direct check, retrieved 2026-05-27

source: skid


organism: Fluoribacter gormanii

substrate: Nitrocefin


sequence_source: UniProtKB:Q9K578 FASTA direct check, retrieved 2026-05-27


substrate_name: cefotaxime

substrate: cefotaxime


substrate_name: Cefuroxime

sequence_source: UniProtKB:Q6SJ61 direct lookup; live TrEMBL Escherichia coli beta-lactamase, EC 3.5.2.6, sequence version 1; checked 2026-05-27

column_label: Table 4, substrate row 'Cefuroxime', enzyme column 'TEM-1 WT': kcat column = 6+1; Km column = 1050+150 (uM); kcat/Km column = 5.7+1.3 (mM-1 s-1).

normalized_value_unit_evidence: kcat: printed Table 4 cell 6 (Cefuroxime, TEM-1 WT); no unit conversion, value already s-1; exported value 6.0 s-1. Km: printed Table 4 cell 1050 uM; 1050 / 1000 = 1.05 mM; exported value 1.05 mM. kcat/Km: derived as the exact quotient of the paper's own kcat and Km cells, 6 / 1.05 = 5.714285714285714 s-1 mM-1, matching the exported kcat_over_km; the paper's own printed cell rounds to 5.7 at its own one-decimal precision, consistent with this quotient.

raw_value_unit_evidence: Table 4, substrate row Cefuroxime, TEM-1 WT columns: kcat = 6+1; Km = 1050+150 (uM); printed kcat/Km = 5.7+1.3 (mM-1 s-1).

row_label: Table 4, substrate row 'Cefuroxime', TEM-1 WT columns

table_label: Table 4: Kinetic parameters for the WT and mutant TEM enzymes (Biochem. J. 1994, 301:485-494)

substrate: Cefuroxime


substrate: Penicillin G


sequence_source: UniProt Q9K578 FASTA direct check on 2026-05-27

column_label: Official JBC Table II, WT cefotaxime, [Zn2+] = 100 uM: kcat 430 s^-1; Km 70 uM = 0.07 mM; printed kcat/Km 6.1 uM^-1 s^-1 = 6100 s^-1 mM^-1. Current 6142.857142857142 lies in rounding interval [6050, 6150) s^-1 mM^-1.

normalized_value_unit_evidence: The same high-zinc row normalizes to kcat=430 s^-1 and Km=0.07 mM. Their stored-precision quotient is 430 / 0.07 = 6142.857142857142 s^-1 mM^-1. The independently printed efficiency 6.1 uM^-1 s^-1 normalizes separately to 6100 s^-1 mM^-1.

raw_value_unit_evidence: kcat raw_value=430 raw_unit=s^-1; Km raw_value=70 raw_unit=uM; printed kcat/Km raw_value=6.1 raw_unit=uM^-1 s^-1

row_label: WT / cefotaxime / [Zn2+] = 100 uM

table_label: Table II: Kinetic parameters of the wild type enzyme (WT) and FEZ-1 mutant enzymes


substrate_name: Imipenem

substrate: Imipenem


sequence_source: UniProtKB Q9K578 FASTA direct lookup; canonical wild-type FEZ-1 sequence, 282 aa.


substrate_name: Meropenem

substrate: Meropenem


sequence_source: UniProt Q9K578 canonical sequence; PubMed 15159411 mutant context; RCSB FEZ-1 numbering map from 1L9Y/5WCK maps Y156A to UniProt residue 130; single substitution Y130A reconstructed.

sequence_variant_note: Resolved sequence already matches the mutant residue(s) after applying an inferred residue-numbering offset +6, so it is treated as a source-provided variant sequence.


sequence_source: UniProt Q9K578 canonical sequence; PubMed 15159411 mutant context; RCSB FEZ-1 numbering map from 1L9Y/5WCK maps N225A to UniProt residue 197; single substitution N197A reconstructed.

sequence_variant_note: Mutation signature N225A could not be applied safely because the resolved sequence does not match the expected reference residue(s).


substrate_name: Nitrocefin

sequence_source: UniProt Q9K578 canonical sequence; PubMed 15159411 mutant context; RCSB FEZ-1 numbering map from 1L9Y/5WCK maps S221A to UniProt residue 193; single substitution S193A reconstructed.

sequence_variant_note: Mutation signature S221A could not be applied safely because the resolved sequence does not match the expected reference residue(s).


substrate_name: 7-Aminocephalosporanic acid

sequence_source: UniProt Q9K578 canonical sequence; PubMed 15159411 mutant context; RCSB FEZ-1 numbering map from 1L9Y/5WCK maps Y228A to UniProt residue 200; single substitution Y200A reconstructed.

sequence_variant_note: Mutation signature Y228A matches the mutant residue at offset +7 and the reference residue at offset -13; variant reconstruction was not applied because multiple plausible residue-numbering offsets are present.

substrate: 7-Aminocephalosporanic acid


sequence_source: UniProtKB Q9K578 FASTA direct lookup on 2026-05-27


sequence_variant_note: Mutation context is present, but no sequence was resolved for this record.


organism: Klebsiella pneumoniae

sequence_source: UniProtKB:Q8GD10 direct accession lookup on 2026-05-27

column_label: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes; CTX-M-26 column block: kcat (s^-1) / Km (uM) / kcat per Km (uM^-1 s^-1); Cefuroxime row

normalized_value_unit_evidence: kcat 21.0 s^-1; Km 0.3 mM; kcat_over_km 70.0 s^-1 mM^-1 as the quotient of the same TABLE 3 row and same CTX-M-26 column-block kcat and Km cells; the paper's own printed ratio cell reads 0.07 uM^-1 s^-1 = 70.0 s^-1 mM^-1

raw_value_unit_evidence: kcat 21 s^-1; Km 300 uM; printed kcat/Km 0.07 uM^-1 s^-1

row_label: Cefuroxime row; CTX-M-26 column block (last three numeric cells)


column_label: Antimicrobial Agents and Chemotherapy 48(12):4829-4834 (2004); TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes; CTX-M-26 column group; substrate row 'Cefotaxime': column 'kcat (s^-1)' = 120; column 'Km (uM)' = 150; column 'kcat/Km (uM^-1 s^-1)' = 0.77.

normalized_value_unit_evidence: Printed kcat 120 s^-1 is already the catalog unit s^(-1); no conversion needed; catalog kcat = 120.0. Printed Km 150 uM / 1000 = 0.15 mM, matching the catalog km 0.15 mM exactly. The paper does print a kcat/Km cell for this row, 0.77 uM^-1 s^-1 = 770.0 s^(-1)*mM^(-1), but that printed cell is NOT the catalog value: the catalog kcat_over_km 800.0 s^(-1)*mM^(-1) is the exact full-precision quotient of this row's own printed pair, 120.0 / 0.15. The printed cell is rounded (and for Benzylpenicillin is additionally off by a factor of ten against the paper's own pair), so the ratio is typed derived_same_measurement and the printed cell is documented in prose only.

raw_value_unit_evidence: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes, CTX-M-26 column group, substrate row 'Cefotaxime'; printed kcat (s^-1) 120, printed Km (uM) 150, printed kcat/Km (uM^-1 s^-1) 0.77. Printed units are s^-1 for kcat, uM (micro sign U+03BC) for Km, and uM^-1 s^-1 for kcat/Km; the exponents are U+2212 MINUS SIGN in the source markup.


substrate_name: aztreonam

column_label: Antimicrobial Agents and Chemotherapy 48(12):4829-4834 (2004); TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes; CTX-M-26 column group; substrate row 'Aztreonam': column 'kcat (s^-1)' = 100; column 'Km (uM)' = 130; column 'kcat/Km (uM^-1 s^-1)' = 0.78.

normalized_value_unit_evidence: Printed kcat 100 s^-1 is already the catalog unit s^(-1); no conversion needed; catalog kcat = 100.0. Printed Km 130 uM / 1000 = 0.13 mM, matching the catalog km 0.13 mM exactly. The paper does print a kcat/Km cell for this row, 0.78 uM^-1 s^-1 = 780.0 s^(-1)*mM^(-1), but that printed cell is NOT the catalog value: the catalog kcat_over_km 769.2307692307692 s^(-1)*mM^(-1) is the exact full-precision quotient of this row's own printed pair, 100.0 / 0.13. The printed cell is rounded (and for Benzylpenicillin is additionally off by a factor of ten against the paper's own pair), so the ratio is typed derived_same_measurement and the printed cell is documented in prose only.

raw_value_unit_evidence: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes, CTX-M-26 column group, substrate row 'Aztreonam'; printed kcat (s^-1) 100, printed Km (uM) 130, printed kcat/Km (uM^-1 s^-1) 0.78. Printed units are s^-1 for kcat, uM (micro sign U+03BC) for Km, and uM^-1 s^-1 for kcat/Km; the exponents are U+2212 MINUS SIGN in the source markup.

substrate: aztreonam


column_label: Antimicrobial Agents and Chemotherapy 48(12):4829-4834 (2004); TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes; CTX-M-26 column group; substrate row 'Cephalothin': column 'kcat (s^-1)' = 530; column 'Km (uM)' = 110; column 'kcat/Km (uM^-1 s^-1)' = 4.7.

normalized_value_unit_evidence: Printed kcat 530 s^-1 is already the catalog unit s^(-1); no conversion needed; catalog kcat = 530.0. Printed Km 110 uM / 1000 = 0.11 mM, matching the catalog km 0.11 mM exactly. The paper does print a kcat/Km cell for this row, 4.7 uM^-1 s^-1 = 4700.0 s^(-1)*mM^(-1), but that printed cell is NOT the catalog value: the catalog kcat_over_km 4818.181818181818 s^(-1)*mM^(-1) is the exact full-precision quotient of this row's own printed pair, 530.0 / 0.11. The printed cell is rounded (and for Benzylpenicillin is additionally off by a factor of ten against the paper's own pair), so the ratio is typed derived_same_measurement and the printed cell is documented in prose only.

raw_value_unit_evidence: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes, CTX-M-26 column group, substrate row 'Cephalothin'; printed kcat (s^-1) 530, printed Km (uM) 110, printed kcat/Km (uM^-1 s^-1) 4.7. Printed units are s^-1 for kcat, uM (micro sign U+03BC) for Km, and uM^-1 s^-1 for kcat/Km; the exponents are U+2212 MINUS SIGN in the source markup.


organism: Klebsiella oxytoca

substrate_name: amoxicillin

column_label: Table 2, TEM-59 enzyme block; row Amoxicillin; column k cat (s^-1) cell 110; column K m (uM) cell 520; column k cat / K m (uM^-1 s^-1) cell 0.2.

normalized_value_unit_evidence: kcat 110 s^-1 = 110.0 s^(-1). Km 520 uM = 520 / 1000 = 0.52 mM. kcat/Km is recorded as the quotient of this row's own two printed cells: 110 s^-1 / 0.52 mM = 211.53846153846152 s^-1 mM^-1. Table 2 prints the ratio cell only to two significant figures (0.2 uM^-1 s^-1); that printed cell is the rounding of the same quotient and does not contradict it.

raw_value_unit_evidence: Table 2 of the PMC HTML asset, row Amoxicillin, TEM-59 enzyme block: kcat column cell 110 s^-1; Km column cell 520 uM; kcat/Km column cell 0.2 uM^-1 s^-1.

row_label: Amoxicillin

table_label: TABLE 2. Kinetics parameters of TEM-89 beta-lactamase compared with those of TEM-2, TEM-3, and TEM-59 beta-lactamases

substrate: amoxicillin


column_label: Table 2, TEM-59 enzyme block; row Benzylpenicillin; column k cat (s^-1) cell 200; column K m (uM) cell 140; column k cat / K m (uM^-1 s^-1) cell 1.4.

normalized_value_unit_evidence: kcat 200 s^-1 = 200.0 s^(-1). Km 140 uM = 140 / 1000 = 0.14 mM. kcat/Km is recorded as the quotient of this row's own two printed cells: 200 s^-1 / 0.14 mM = 1428.5714285714284 s^-1 mM^-1. Table 2 prints the ratio cell only to two significant figures (1.4 uM^-1 s^-1); that printed cell is the rounding of the same quotient and does not contradict it.

raw_value_unit_evidence: Table 2 of the PMC HTML asset, row Benzylpenicillin, TEM-59 enzyme block: kcat column cell 200 s^-1; Km column cell 140 uM; kcat/Km column cell 1.4 uM^-1 s^-1.


substrate_name: piperacillin

column_label: Table 2, TEM-59 enzyme block; row Piperacillin; column k cat (s^-1) cell 360; column K m (uM) cell 120; column k cat / K m (uM^-1 s^-1) cell 3.0.

normalized_value_unit_evidence: kcat 360 s^-1 = 360.0 s^(-1). Km 120 uM = 120 / 1000 = 0.12 mM. kcat/Km 3.0 uM^-1 s^-1 = 3.0 * 1000 = 3000.0 s^-1 mM^-1, which is also the exact quotient of this row's own printed cells.

raw_value_unit_evidence: Table 2 of the PMC HTML asset, row Piperacillin, TEM-59 enzyme block: kcat column cell 360 s^-1; Km column cell 120 uM; kcat/Km column cell 3.0 uM^-1 s^-1.

substrate: piperacillin


substrate_name: Ceftazidime

sequence_source: UniProtKB:Q8GD10 direct REST lookup on 2026-05-27

assay_conditions_summary: pH 7; 310.15 K; buffer 100 mM sodium phosphate

column_label: Table label: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes a. Row: Ceftazidime. Enzyme column group: CTX-M-26. Columns read: k cat (s^-1) cell 0.015, K m (uM) cell 3,300, k cat / K m (uM^-1 s^-1) cell ND. metric: kcat; raw value: 0.015; raw unit: s^-1; normalized value: 0.015 s^(-1); metric: Km; raw value: 3,300; raw unit: uM; normalized value: 3.3 mM; metric: kcat/Km; raw value: none printed (cell reads ND), derived from this row's own CTX-M-26 kcat and Km cells; raw unit: s^-1 mM^-1; normalized value: 0.004545454545454545 s^-1 mM^-1; assay condition: Purified CTX-M-26 beta-lactamase (recombinant); purified beta-lactamases were then used for kinetic measurements, which were performed at 37 C in 100 mM sodium phosphate buffer (pH 7. The bla CTX-M-26 gene was detected on a 100-kb plasmid isolated from a Klebsiella pneumoniae strain from the United Kingdom.

normalized_value_unit_evidence: CTX-M-26 columns of TABLE 3 row Ceftazidime: kcat 0.015 s^-1 = 0.015 s^(-1) (no conversion); Km 3,300 uM = 3.3 mM (1 uM = 0.001 mM, and the printed thousands comma in `3,300` is a digit-group separator, so the cell is three thousand three hundred micromolar); kcat/Km is printed ND in this cell, so the export ratio is the quotient of this same row's own CTX-M-26 cells: 0.015 s^-1 / 3.3 mM = 0.004545454545454545 s^-1 mM^-1. In the on-disk text the micro sign renders as μ, the superscript minus one as −1, and superscripts are flattened, so `k cat (s −1 )` is the paper's k_cat (s^-1) and `K m (μM)` is the paper's K_m (uM).

raw_value_unit_evidence: TABLE 3. Steady-state kinetics of purified CTX-M-25 and CTX-M-26 enzymes a | enzyme column group header row: Substrate CTX-M-25 CTX-M-26; metric header row: k cat (s −1 ) K m (μM) k cat / K m (μM −1 s −1 ) k cat (s −1 ) K m (μM) k cat / K m (μM −1 s −1 ) | row: Ceftazidime 33 13 2.6 0.015 3,300 ND | the first three cells belong to CTX-M-25 and are not used here; the CTX-M-26 cells read: k cat = 0.015 s^-1; K m = 3,300 uM; k cat / K m = ND (not determinable).

row_label: CTX-M-26 | Ceftazidime

substrate: Ceftazidime


column_label: Table 4. Kinetic parameters of CTX-M-25 and CTX-M-26 beta-lactamases; row Ampicillin; CTX-M-26 columns kcat (s^-1), Km (uM), kcat/Km (uM^-1 s^-1); cells 12, 24, 0.5

raw_value_unit_evidence: CTX-M-26 / Ampicillin: kcat=12 s^-1; Km=24 uM; kcat/Km=0.5 uM^-1 s^-1

row_label: CTX-M-26 / Ampicillin


sequence_source: UniProtKB:P0AD64 canonical sequence checked on 2026-05-27; row-specific R244S variant not reconstructed

sequence_variant_note: Canonical sequence is preserved, but mutation context is present; variant sequence was not attached without safely applying the mutation.


sequence_source: UniProtKB:P0AD64 canonical sequence checked on 2026-05-27; row-specific R244L variant not reconstructed


sequence_source: UniProtKB:P0AD64 canonical sequence checked on 2026-05-27; row-specific R244Q variant not reconstructed


sequence_source: UniProt Q9K578 REST accession lookup on 2026-05-27

column_label: Official JBC Table II, WT Nitrocefin, [Zn2+] = 100 uM: kcat 600 s^-1; Km 190 uM = 0.19 mM; printed kcat/Km 3.2 uM^-1 s^-1 = 3200 s^-1 mM^-1. Current 3157.8947368421054 lies in rounding interval [3150, 3250) s^-1 mM^-1.

normalized_value_unit_evidence: The same high-zinc row normalizes to kcat=600 s^-1 and Km=0.19 mM. Their stored-precision quotient is 600 / 0.19 = 3157.8947368421054 s^-1 mM^-1. The independently printed efficiency 3.2 uM^-1 s^-1 normalizes separately to 3200 s^-1 mM^-1.

raw_value_unit_evidence: kcat raw_value=600 raw_unit=s^-1; Km raw_value=190 raw_unit=uM; printed kcat/Km raw_value=3.2 raw_unit=uM^-1 s^-1

row_label: WT / Nitrocefin / [Zn2+] = 100 uM


substrate_name: meropenem

substrate: meropenem


substrate_name: panipenem

substrate: panipenem


substrate_name: ampicillin

substrate: ampicillin


sequence_variant_note: Resolved canonical sequence from UniProtKB:P0AD64 canonical sequence retrieved 2026-05-27; D104K reconstructed by applying the SHV/Ambler D104K change to the P0AD64 sequence at computed sequence coordinate 100. and applied mutation signature D104K with inferred residue-numbering offset -4 to reconstruct the assayed variant sequence.


sequence_source: UniProtKB:P0AD64 canonical sequence retrieved 2026-05-27; D104K reconstructed by applying the SHV/Ambler D104K change to the P0AD64 sequence at computed sequence coordinate 100.


substrate_name: Ampicillin

sequence_source: UniProtKB:P0AD64 canonical sequence retrieved 2026-05-27.

substrate: Ampicillin


sequence_variant_note: Resolved canonical sequence from UniProtKB:P0AD64 canonical sequence retrieved 2026-05-27; G238S reconstructed by applying the SHV/Ambler G238S change to the P0AD64 sequence at computed sequence coordinate 234. and applied mutation signature G238S with inferred residue-numbering offset -4 to reconstruct the assayed variant sequence.


sequence_source: UniProtKB:P0AD64 canonical sequence retrieved 2026-05-27; G238S reconstructed by applying the SHV/Ambler G238S change to the P0AD64 sequence at computed sequence coordinate 234.


substrate_name: cefepime

sequence_source: UniProtKB:Q8KQ59 exact accession REST lookup, accessed 2026-05-27

substrate: cefepime


substrate_name: cephalotin

substrate: cephalotin


substrate_name: ceftazidime

substrate: ceftazidime


substrate_name: cefoxitin

substrate: cefoxitin


substrate_name: doripenem

substrate: doripenem


substrate_name: Cephalothin

sequence_source: UniProtKB reviewed accession P0AD64 direct REST/FASTA check

column_label: Table 4, Cephalothin block, enzyme sub-row `SHV-1` (the dagger-marked reference beta-lactamase, Ratio = 1.00): column `Km (uM)` = 48 +/- 3; column `kcat (s^-1)` = 25.0 +/- 0.7; column `kcat/Km (uM^-1 s^-1)` = 0.50 +/- 0.03; column `Ratio` = 1.00. The variant sub-rows of the same block print Asp104Lys 20 +/- 3 uM with 7.4 +/- 0.1 s^-1, Gly238Ser 3.3 +/- 0.1 uM with 15.0 +/- 0.3 s^-1, and Asp104Lys Gly238Ser 3.0 +/- 0.1 uM with 11.4 +/- 0.3 s^-1.

normalized_value_unit_evidence: Km: paper cell 48 +/- 3 in the column headed `Km (uM)` (micro sign read off the 300 dpi render of journal page 4127); 48.0 uM / 1000 = 0.048 mM, exactly the catalog km 0.048 mM. kcat: paper cell 25.0 +/- 0.7 in the column headed `kcat (s^-1)`; the paper already prints per-second turnover numbers, so no min^-1/60 conversion applies and the value equals the catalog kcat 25.0 s^(-1). kcat/Km: Table 4 prints a kcat/Km cell for this sub-row, 0.50 +/- 0.03 uM^-1 s^-1, which normalizes to 500.0 s^(-1)*mM^(-1) (x 1000 for uM^-1 -> mM^-1). The catalog value 520.8333333333334 s^(-1)*mM^(-1) is NOT that printed cell: it is the exact full-precision quotient of this row's own printed cells, 25.0 s^-1 / 0.048 mM. The printed cell is the two-significant-figure rounding of that quotient, so the two agree to the printed precision while differing as stored numbers. paper_kcat_over_km_s^-1_mM^-1 is therefore left null and the printed cell is documented in prose rather than claimed as the source of the stored value.

raw_value_unit_evidence: Table 4 (journal page 4127), Cephalothin block, enzyme sub-row `SHV-1`: Km = `48 +/- 3` uM; kcat = `25.0 +/- 0.7` s^-1; kcat/Km = `0.50 +/- 0.03` uM^-1 s^-1; Ratio = `1.00`. Table 4 footnote a: data are presented as means +/- standard deviations.

table_label: TABLE 4. Steady-state kinetic parameters

substrate: Cephalothin


substrate: Nitrocefin


substrate_name: cefalotin

substrate: cefalotin


substrate_name: nitrocefin

substrate: nitrocefin


sequence_source: UniProtKB:Q9F918 direct REST lookup on 2026-05-27

column_label: PMID 29228168 Table 3. Kinetics analysis of SHV-14 and its mutated proteins.; substrate sub-header Nitrocefin; SHV-14 (wild type) column; printed cells Km 45 ± 1.7 uM, kcat 5.85 ± 0.2 s^-1, kcat /KM 0.13 s^-1 uM^-1. The paper's printed kcat/KM cell for this row (0.13 s^-1 uM^-1 in the units printed as kcat /KM (s-1 uM-1)) is a rounded two-to-three-significant-figure value; the exported ratio is the exact quotient of this same row's two printed primary cells, so the printed cell is reported here but is not used as a raw value.

raw_value_unit_evidence: Table row as printed (SHV-14 wild-type column): Km 45 ± 1.7 uM; kcat 5.85 ± 0.2 s^-1; kcat /KM 0.13 s^-1 uM^-1.

row_label: Nitrocefin / SHV-14 column (wild type)


substrate_name: cefoperazone

column_label: PMID 29228168 Table 3. Kinetics analysis of SHV-14 and its mutated proteins.; substrate sub-header Cefoperazone; SHV-14 (wild type) column; printed cells Km 57.4 ± 6 uM, kcat 229.5 ± 10.6 s^-1, kcat /KM 4 s^-1 uM^-1. The paper's printed kcat/KM cell for this row (4 s^-1 uM^-1 in the units printed as kcat /KM (s-1 uM-1)) is a rounded two-to-three-significant-figure value; the exported ratio is the exact quotient of this same row's two printed primary cells, so the printed cell is reported here but is not used as a raw value.

raw_value_unit_evidence: Table row as printed (SHV-14 wild-type column): Km 57.4 ± 6 uM; kcat 229.5 ± 10.6 s^-1; kcat /KM 4 s^-1 uM^-1.

row_label: Cefoperazone / SHV-14 column (wild type)

substrate: cefoperazone


substrate_name: cefuroxime

sequence_source: UniProtKB Q8KQ59 FASTA checked 2026-05-27; cross-checked GenBank AY101764/AAM52215.1 translation.

substrate: cefuroxime


substrate_name: aztreonam

substrate: aztreonam


substrate_name: cefotaxime

substrate: cefotaxime


substrate_name: piperacillin

substrate: piperacillin


substrate_name: Ceftazidime

sequence_source: UniProtKB C7C422 FASTA/REST checked 2026-05-27

assay_conditions_summary: pH 7; 303.15 K; buffer dilution

column_label: The literal Ceftazidime/Wild type NDM-1 row binds substrate, variant, Km, kcat, and printed efficiency. Current Km is the stored-precision rounding of the printed cell.

normalized_value_unit_evidence: paper Km=0.03843 mM, rounded current Km=0.038 mM; kcat=119.2 s^-1; current same-row quotient=3136.842105263158; printed efficiency=3102 +/- 178.6 s^-1 mM^-1.

row_label: Ceftazidime | Wild type NDM-1

table_label: Table 2 Steady-state enzyme kinetics of wild-type NDM-1 enzyme and NDM-1Q123A mutant enzyme

substrate: Ceftazidime


substrate_name: Nitrocefin

column_label: The literal Nitrocefin/Wild type NDM-1 row binds substrate, variant, Km, kcat, and printed efficiency. Current Km is the stored-precision rounding of the printed cell.

normalized_value_unit_evidence: paper Km=0.01272 mM, rounded current Km=0.013 mM; kcat=1.332 s^-1; current same-row quotient=102.46153846153847 s^-1 mM^-1; printed efficiency=104 +/- 475.1 s^-1 mM^-1.

row_label: Nitrocefin | Wild type NDM-1


sequence_source: UniProtKB C7C422 FASTA/REST checked 2026-05-27; Q123A reconstructed from canonical residue 123 Q and PMID 29454953 mutation description

sequence_variant_note: Resolved sequence already matches the mutant residue(s), so it is treated as a source-provided variant sequence.


column_label: The literal Ampicillin/Wild type NDM-1 row binds substrate, variant, Km, kcat, and printed efficiency.

row_label: Ampicillin | Wild type NDM-1


substrate_name: Meropenem

substrate: Meropenem


column_label: PMID 29228168 Table 3. Kinetics analysis of SHV-14 and its mutated proteins.; substrate sub-header Piperacillin; SHV-14 (wild type) column; printed cells Km 58 ± 3 uM, kcat 677 ± 7 s^-1, kcat /KM 11.6 s^-1 uM^-1. The paper's printed kcat/KM cell for this row (11.6 s^-1 uM^-1 in the units printed as kcat /KM (s-1 uM-1)) is a rounded two-to-three-significant-figure value; the exported ratio is the exact quotient of this same row's two printed primary cells, so the printed cell is reported here but is not used as a raw value.

raw_value_unit_evidence: Table row as printed (SHV-14 wild-type column): Km 58 ± 3 uM; kcat 677 ± 7 s^-1; kcat /KM 11.6 s^-1 uM^-1.

row_label: Piperacillin / SHV-14 column (wild type)


substrate_name: ampicillin

sequence_variant_note: Resolved canonical sequence from UniProtKB:Q9F918 and applied mutation signature E164A to reconstruct the assayed variant sequence.

substrate: ampicillin


substrate_name: amoxicillin

substrate: amoxicillin


sequence_variant_note: Resolved canonical sequence from UniProtKB:Q9F918 and applied mutation signature E162A to reconstruct the assayed variant sequence.


substrate_name: cephalothin

column_label: PMID 29228168 Table 3. Kinetics analysis of SHV-14 and its mutated proteins.; substrate sub-header Cephalothin; SHV-14 (wild type) column; printed cells Km 45 ± 5 uM, kcat 113 ± 21 s^-1, kcat /KM 2.5 s^-1 uM^-1. The paper's printed kcat/KM cell for this row (2.5 s^-1 uM^-1 in the units printed as kcat /KM (s-1 uM-1)) is a rounded two-to-three-significant-figure value; the exported ratio is the exact quotient of this same row's two printed primary cells, so the printed cell is reported here but is not used as a raw value.

raw_value_unit_evidence: Table row as printed (SHV-14 wild-type column): Km 45 ± 5 uM; kcat 113 ± 21 s^-1; kcat /KM 2.5 s^-1 uM^-1.

row_label: Cephalothin / SHV-14 column (wild type)

substrate: cephalothin


column_label: Table 3 (Kinetics analysis of SHV-14 and its mutated proteins); the three enzyme column heads are 'SHV-14', 'SHV-14_E162A' and 'SHV-14_E164A'; this record reads the first of them, the wild-type column. Antibiotic block 'Ampicillin'; metric row 'Km (uM)' = 32; metric row 'kcat (s^-1)' = 544; metric row 'kcat/KM (s^-1 uM^-1)' = 8.5.

normalized_value_unit_evidence: Km: printed Table 3 cell 32 uM for the Ampicillin block, wild-type SHV-14 column; 32 / 1000 = 0.032 mM; the exported value is 0.032 mM. kcat: printed Table 3 cell 544 s^-1 for the same cell tuple; already in s^-1, no conversion (this paper prints no min^-1 kinetic cell); the exported value is 544.0 s^(-1). kcat/Km: printed Table 3 cell 8.5 s^-1 uM^-1 for the same cell tuple; 1 s^-1 uM^-1 is 1000 s^-1 mM^-1, so 8.5 x 1000 = 8500.0 s^-1 mM^-1; the exported value is 17000.0 s^(-1)*mM^(-1), so this metric is corrected to the printed cell.

raw_value_unit_evidence: Table 3, antibiotic block 'Ampicillin', enzyme column 'SHV-14' (the wild-type column): Km = 32 uM; kcat = 544 s^-1; printed kcat/KM = 8.5 s^-1 uM^-1.

table_label: Table 3: Kinetics analysis of SHV-14 and its mutated proteins (FEMS Microbiology Letters 2018, 365, article fnx259)


sequence_source: UniProtKB Q9F918 REST lookup on 2026-05-27; canonical residue 162 was E and was changed to A for the selected E162A row.


sequence_source: UniProtKB Q9F918 REST lookup on 2026-05-27; canonical residue 164 was E and was changed to A for the selected E164A row.


substrate_name: Oxacillin

sequence_source: UniProtKB Q6XEC0 FASTA direct lookup

substrate: Oxacillin


substrate_name: Temocillin

substrate: Temocillin


substrate_name: Faropenem

substrate: Faropenem


substrate_name: temocillin

proof_lines:
pH 7.0, 30°C
Raw SKiD Env: Temp=30°C, pH=7

source_db: brenda

substrate: temocillin


substrate_name: Ertapenem

substrate: Ertapenem


substrate: Nitrocefin


substrate_name: Imipenem

substrate: Imipenem


substrate_name: Ampicillin

sequence_source: Reconstructed from UniProtKB C7C422 FASTA by Q123A after direct residue check on 2026-05-27.

substrate: Ampicillin


substrate_name: cefoxitin

substrate: cefoxitin


sequence_source: UniProtKB C7C422 FASTA via UniProt REST; direct check on 2026-05-27.


column_label: The literal Cefotaxime/Wild type NDM-1 row binds substrate, variant, Km, kcat, and printed efficiency. Current Km is the stored-precision rounding of the printed cell.

normalized_value_unit_evidence: paper Km=0.03194 mM, rounded current Km=0.032 mM; kcat=84.84 s^-1; current same-row quotient=2651.25; printed efficiency=2631 +/- 347.1 s^-1 mM^-1.

row_label: Cefotaxime | Wild type NDM-1


organism: Moraxella catarrhalis

substrate_name: Loracarbef

sequence_source: UniProtKB:Q49095 direct accession lookup, 2026-05-27

column_label: Table 3 row 'Loracarbef', BRO-2p sub-column of each column group: Km 38 uM, kcat 95 s^-1, Specificity 2.5 in units of 10^6 M^-1 s^-1 (footnote b, L . s-1 . umol-1). Km 38 uM normalizes to 0.038 mM and kcat 95 s^-1 divided by that Km gives 2.5E+3 s^-1 mM^-1, which is the currently exported kcat/Km for this identity.

normalized_value_unit_evidence: Km 38 uM = 0.038 mM; kcat 95 s^-1; kcat/Km = 95 / 38 (s^-1 per uM) = 2500 s^-1 mM^-1. The printed Specificity cell 2.5 x 10^6 M^-1 s^-1 is that same quotient carried to the two significant figures the column prints.

raw_value_unit_evidence: Table 3 row Loracarbef, BRO-2p columns: Km 38 uM; kcat 95 s^-1; Specificity 2.5 (10^6 M^-1 s^-1).

row_label: Loracarbef | BRO-2p column

table_label: Table 3: Kinetic constants of the BRO-lp and BRO-2p 13-1actamases of Branhamella catarrhalis as determined speetrophotometrieally using the Tl/2 method.

substrate: Loracarbef


substrate_name: mecillinam

column_label: Table 3 row 'MeeiUinam', BRO-2p sub-column of each column group: Km 63 uM, kcat 29 s^-1, Specificity 0.46 in units of 10^6 M^-1 s^-1 (footnote b, L . s-1 . umol-1). Km 63 uM normalizes to 0.063 mM and kcat 29 s^-1 divided by that Km gives 460.3174603174603174603174603174603 s^-1 mM^-1, which is the currently exported kcat/Km for this identity.

normalized_value_unit_evidence: Km 63 uM = 0.063 mM; kcat 29 s^-1; kcat/Km = 29 / 63 (s^-1 per uM) = 460.3174603174603174603174603174603 s^-1 mM^-1. The printed Specificity cell 0.46 x 10^6 M^-1 s^-1 is that same quotient carried to the two significant figures the column prints.

raw_value_unit_evidence: Table 3 row MeeiUinam, BRO-2p columns: Km 63 uM; kcat 29 s^-1; Specificity 0.46 (10^6 M^-1 s^-1).

row_label: MeeiUinam | BRO-2p column

substrate: mecillinam


sequence_source: UniProtKB:Q59514 direct accession lookup, 2026-05-27

column_label: Table 3 row 'Loracarbef', BRO-1p sub-column of each column group: Km 50 uM, kcat 79 s^-1, Specificity 1.6 in units of 10^6 M^-1 s^-1 (footnote b, L . s-1 . umol-1). Km 50 uM normalizes to 0.05 mM and kcat 79 s^-1 divided by that Km gives 1.58E+3 s^-1 mM^-1, which is the currently exported kcat/Km for this identity.

normalized_value_unit_evidence: Km 50 uM = 0.05 mM; kcat 79 s^-1; kcat/Km = 79 / 50 (s^-1 per uM) = 1580 s^-1 mM^-1. The printed Specificity cell 1.6 x 10^6 M^-1 s^-1 is that same quotient carried to the two significant figures the column prints.

raw_value_unit_evidence: Table 3 row Loracarbef, BRO-1p columns: Km 50 uM; kcat 79 s^-1; Specificity 1.6 (10^6 M^-1 s^-1).

row_label: Loracarbef | BRO-1p column


substrate_name: Cephalosporin C

column_label: Table 3: Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method. Substrate row 'Cephalosporin C'; enzyme column 'BRO-1p'; column 'Km^a (uM)' = 3.9; column 'kcat^b (s^-1)' = 5.0; column 'Specificity (kcat/Km)' = 1.3 (footnote b: L . s^-1 . umol^-1).

normalized_value_unit_evidence: Km: printed Table 3 cell 3.9 uM; 3.9 / 1000 = 0.0039 mM; the exported value is 0.004 mM. kcat: printed Table 3 cell 5.0 s^-1; already in s^-1, no conversion (this paper prints no min^-1 kinetic cell); the exported value is 5.0 s^(-1). kcat/Km: printed Table 3 Specificity cell 1.3 L . s^-1 . umol^-1; footnote b prints that unit literal and 1 L . s^-1 . umol^-1 is 1 s^-1 uM^-1, so 1.3 x 1000 = 1300.0 s^-1 mM^-1; the exported value is 1250.0 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table 3 (journal page 318), substrate row 'Cephalosporin C', enzyme column 'BRO-1p': Km = 3.9 uM; kcat = 5.0 s^-1; printed Specificity (kcat/Km) = 1.3 L . s^-1 . umol^-1.

row_label: Table 3, substrate row 'Cephalosporin C', enzyme column 'BRO-1p' (Branhamella catarrhalis strain L14)

substrate: Cephalosporin C


substrate_name: Cephalothin

column_label: Table 3: Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method. Substrate row 'Cephalothin'; enzyme column 'BRO-2p'; column 'Km^a (uM)' = 1.2; column 'kcat^b (s^-1)' = 4.6; column 'Specificity (kcat/Km)' = 4.0 (footnote b: L . s^-1 . umol^-1).

normalized_value_unit_evidence: Km: printed Table 3 cell 1.2 uM; 1.2 / 1000 = 0.0012 mM; the exported value is 0.001 mM. kcat: printed Table 3 cell 4.6 s^-1; already in s^-1, no conversion (this paper prints no min^-1 kinetic cell); the exported value is 4.6 s^(-1). kcat/Km: printed Table 3 Specificity cell 4.0 L . s^-1 . umol^-1; footnote b prints that unit literal and 1 L . s^-1 . umol^-1 is 1 s^-1 uM^-1, so 4.0 x 1000 = 4000.0 s^-1 mM^-1; the exported value is 4600.0 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table 3 (journal page 318), substrate row 'Cephalothin', enzyme column 'BRO-2p': Km = 1.2 uM; kcat = 4.6 s^-1; printed Specificity (kcat/Km) = 4.0 L . s^-1 . umol^-1.

row_label: Table 3, substrate row 'Cephalothin', enzyme column 'BRO-2p' (Branhamella catarrhalis strain L16904)

substrate: Cephalothin


column_label: Table 3 row 'Cephalothin', BRO-1p sub-column of each column group: Km 0.9 uM, kcat 4.9 s^-1, Specificity 5.5 in units of 10^6 M^-1 s^-1 (footnote b, L . s-1 . umol-1). Km 0.9 uM normalizes to 0.0009 mM and kcat 4.9 s^-1 divided by that Km gives 5444.444444444444444444444444444444 s^-1 mM^-1, which is the currently exported kcat/Km for this identity.

normalized_value_unit_evidence: Km 0.9 uM = 0.0009 mM; kcat 4.9 s^-1; kcat/Km = 4.9 / 0.9 (s^-1 per uM) = 5444.444444444444444444444444444444 s^-1 mM^-1. The printed Specificity cell 5.5 x 10^6 M^-1 s^-1 is that same quotient carried to the two significant figures the column prints.

raw_value_unit_evidence: Table 3 row Cephalothin, BRO-1p columns: Km 0.9 uM; kcat 4.9 s^-1; Specificity 5.5 (10^6 M^-1 s^-1).

row_label: Cephalothin | BRO-1p column


substrate_name: Cephaloridine

column_label: Table 3: Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method. Substrate row 'Cephaloridine'; enzyme column 'BRO-1p'; column 'Km^a (uM)' = 1.7; column 'kcat^b (s^-1)' = 4.8; column 'Specificity (kcat/Km)' = 2.8 (footnote b: L . s^-1 . umol^-1).

normalized_value_unit_evidence: Km: printed Table 3 cell 1.7 uM; 1.7 / 1000 = 0.0017 mM; the exported value is 0.002 mM. kcat: printed Table 3 cell 4.8 s^-1; already in s^-1, no conversion (this paper prints no min^-1 kinetic cell); the exported value is 4.8 s^(-1). kcat/Km: printed Table 3 Specificity cell 2.8 L . s^-1 . umol^-1; footnote b prints that unit literal and 1 L . s^-1 . umol^-1 is 1 s^-1 uM^-1, so 2.8 x 1000 = 2800.0 s^-1 mM^-1; the exported value is 2400.0 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table 3 (journal page 318), substrate row 'Cephaloridine', enzyme column 'BRO-1p': Km = 1.7 uM; kcat = 4.8 s^-1; printed Specificity (kcat/Km) = 2.8 L . s^-1 . umol^-1.

row_label: Table 3, substrate row 'Cephaloridine', enzyme column 'BRO-1p' (Branhamella catarrhalis strain L14)

substrate: Cephaloridine


sequence_variant_note: Resolved canonical sequence from UniProtKB:E9NWK5 canonical sequence fetched during review; L209F reconstructed after confirming residue 209 is L. and applied mutation signature L209F to reconstruct the assayed variant sequence.


substrate_name: Meropenem

sequence_source: UniProtKB:E9NWK5 canonical sequence fetched during review; L209F reconstructed after confirming residue 209 is L.

substrate: Meropenem


substrate_name: biapenem

substrate: biapenem


substrate_name: cefazolin

substrate: cefazolin


substrate_name: Penicillin G

substrate: Penicillin G


substrate_name: H2O; Imipenem

proof_lines: SABIO-RK modifier species: beta-lactamase(Enzyme) mutant L209F

substrate: H2O; Imipenem


substrate_name: carbenicillin

substrate: carbenicillin


organism: Kluyvera ascorbata

substrate_name: Nitrocefin

sequence_source: UniProtKB:Q8VKT5 direct REST lookup on 2026-05-27

sequence_variant_note: Sequence is treated as wild-type because the source explicitly marked the record as wild-type.


sequence_source: UniProtKB:Q49095 direct REST lookup on 2026-05-27

column_label: Table 3: Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method. Substrate row 'Cephaloridine'; enzyme column 'BRO-2p'; column 'Km^a (uM)' = 2.8; column 'kcat^b (s^-1)' = 5.6; column 'Specificity (kcat/Km)' = 2.0 (footnote b: L . s^-1 . umol^-1).

normalized_value_unit_evidence: Km: printed Table 3 cell 2.8 uM; 2.8 / 1000 = 0.0028 mM; the exported value is 0.003 mM. kcat: printed Table 3 cell 5.6 s^-1; already in s^-1, no conversion (this paper prints no min^-1 kinetic cell); the exported value is 5.6 s^(-1). kcat/Km: printed Table 3 Specificity cell 2.0 L . s^-1 . umol^-1; footnote b prints that unit literal and 1 L . s^-1 . umol^-1 is 1 s^-1 uM^-1, so 2.0 x 1000 = 2000.0 s^-1 mM^-1; the exported value is 1866.6666666666665 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table 3 (journal page 318), substrate row 'Cephaloridine', enzyme column 'BRO-2p': Km = 2.8 uM; kcat = 5.6 s^-1; printed Specificity (kcat/Km) = 2.0 L . s^-1 . umol^-1.

row_label: Table 3, substrate row 'Cephaloridine', enzyme column 'BRO-2p' (Branhamella catarrhalis strain L16904)


column_label: Table 3 row 'Cephalosporin C', BRO-2p sub-column of each column group: Km 3.0 uM, kcat 4.7 s^-1, Specificity 1.6 in units of 10^6 M^-1 s^-1 (footnote b, L . s-1 . umol-1). Km 3.0 uM normalizes to 0.003 mM and kcat 4.7 s^-1 divided by that Km gives 1566.666666666666666666666666666667 s^-1 mM^-1, which is the currently exported kcat/Km for this identity.

normalized_value_unit_evidence: Km 3.0 uM = 0.003 mM; kcat 4.7 s^-1; kcat/Km = 4.7 / 3.0 (s^-1 per uM) = 1566.666666666666666666666666666667 s^-1 mM^-1. The printed Specificity cell 1.6 x 10^6 M^-1 s^-1 is that same quotient carried to the two significant figures the column prints.

raw_value_unit_evidence: Table 3 row Cephalosporin C, BRO-2p columns: Km 3.0 uM; kcat 4.7 s^-1; Specificity 1.6 (10^6 M^-1 s^-1).

row_label: Cephalosporin C | BRO-2p column


substrate_name: Cefuroxime

sequence_source: UniProtKB Q59514 reviewed Swiss-Prot BLA1_MORCA; direct lookup 2026-05-27

column_label: Table 3 row 'Cefuroxim¢', BRO-1p sub-column of each column group: Km 68 uM, kcat 4.1 s^-1, Specificity 0.086 in units of 10^6 M^-1 s^-1 (footnote b, L . s-1 . umol-1). Km 68 uM normalizes to 0.068 mM and kcat 4.1 s^-1 divided by that Km gives 60.29411764705882352941176470588235 s^-1 mM^-1, which is the currently exported kcat/Km for this identity.

normalized_value_unit_evidence: Km 68 uM = 0.068 mM; kcat 4.1 s^-1; kcat/Km = 4.1 / 68 (s^-1 per uM) = 60.29411764705882352941176470588235 s^-1 mM^-1. The printed Specificity cell 0.086 x 10^6 M^-1 s^-1 is that same quotient carried to the two significant figures the column prints.

raw_value_unit_evidence: Table 3 row Cefuroxim¢, BRO-1p columns: Km 68 uM; kcat 4.1 s^-1; Specificity 0.086 (10^6 M^-1 s^-1).

row_label: Cefuroxim¢ | BRO-1p column

substrate: Cefuroxime


substrate_name: Methicillin

assay_conditions_summary: pH 7; 303.15 K; buffer 20 mM TEA-HCl / 0.15 M NaCl

column_label: Table 3. Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method; row Methicillin; column group Km^a (uM), column BRO-1p: raw value 34 uM, normalized value 0.034 mM; column group kcat^b (s^-1), column BRO-1p: raw value 168 s^-1, normalized value 168 s^-1; column group Specificity (kcat/Km), column BRO-1p: the table prints 4.9 in units of 10^6 M^-1 s^-1, a two-significant-figure value that agrees with the quotient of this same row and column pair, so the absolute ratio recorded here is that quotient 168 / 0.034 = 4941.176470588235 s^-1 mM^-1.

normalized_value_unit_evidence: metric: kcat; raw value: 168; raw unit: s^-1; normalized value: 168; normalized unit: s^-1; metric: Km; raw value: 34; raw unit: uM; normalized value: 0.034; normalized unit: mM; metric: kcat/Km; the table prints only the rounded specificity column, so the absolute ratio recorded here is the quotient of this row's own two printed cells, paper kcat divided by paper Km; normalized value: 4941.176470588235; normalized unit: s^-1 mM^-1; assay condition: Purified papain-solubilized BRO-1p (strain L14) or BRO-2p (strain L16904) beta-lactamase; spectrophotometric progress curves analysed by the T1/2 method in 20 mM TEA-HCl / 0.15 M NaCl buffer, pH 7.0, at a constant temperature of 30 C.

raw_value_unit_evidence: Table 3. Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method (PDF page 6, journal page 318), row Methicillin: kcat^b (s^-1) column BRO-1p prints 168; Km^a (uM) column BRO-1p prints 34; Specificity (kcat/Km) column BRO-1p prints 4.9 in units of 10^6 M^-1 s^-1. Footnote a: Mean of three values.

row_label: Methicillin

substrate: Methicillin


column_label: Table 3: Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method. Substrate row 'Nitrocefin'; enzyme column 'BRO-1p'; column 'Km^a (uM)' = 6.9; column 'kcat^b (s^-1)' = 151; column 'Specificity (kcat/Km)' = 22 (footnote b: L . s^-1 . umol^-1).

normalized_value_unit_evidence: Km: printed Table 3 cell 6.9 uM; 6.9 / 1000 = 0.0069 mM; the exported value is 0.007 mM. kcat: printed Table 3 cell 151 s^-1; already in s^-1, no conversion (this paper prints no min^-1 kinetic cell); the exported value is 151.0 s^(-1). kcat/Km: printed Table 3 Specificity cell 22 L . s^-1 . umol^-1; footnote b prints that unit literal and 1 L . s^-1 . umol^-1 is 1 s^-1 uM^-1, so 22 x 1000 = 22000.0 s^-1 mM^-1; the exported value is 21571.428571428572 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table 3 (journal page 318), substrate row 'Nitrocefin', enzyme column 'BRO-1p': Km = 6.9 uM; kcat = 151 s^-1; printed Specificity (kcat/Km) = 22 L . s^-1 . umol^-1.

row_label: Table 3, substrate row 'Nitrocefin', enzyme column 'BRO-1p' (Branhamella catarrhalis strain L14)

substrate: Nitrocefin


column_label: Table 3: Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method. Substrate row 'Ampicillin'; enzyme column 'BRO-1p'; column 'Km^a (uM)' = 2.5; column 'kcat^b (s^-1)' = 33; column 'Specificity (kcat/Km)' = 14 (footnote b: L . s^-1 . umol^-1).

normalized_value_unit_evidence: Km: printed Table 3 cell 2.5 uM; 2.5 / 1000 = 0.0025 mM; the exported value is 0.003 mM. kcat: printed Table 3 cell 33 s^-1; already in s^-1, no conversion (this paper prints no min^-1 kinetic cell); the exported value is 33.0 s^(-1). kcat/Km: printed Table 3 Specificity cell 14 L . s^-1 . umol^-1; footnote b prints that unit literal and 1 L . s^-1 . umol^-1 is 1 s^-1 uM^-1, so 14 x 1000 = 14000.0 s^-1 mM^-1; the exported value is 11000.0 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table 3 (journal page 318), substrate row 'Ampicillin', enzyme column 'BRO-1p': Km = 2.5 uM; kcat = 33 s^-1; printed Specificity (kcat/Km) = 14 L . s^-1 . umol^-1.

row_label: Table 3, substrate row 'Ampicillin', enzyme column 'BRO-1p' (Branhamella catarrhalis strain L14)


column_label: Table 3: Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method. Substrate row 'Benzylpenicillin'; enzyme column 'BRO-1p'; column 'Km^a (uM)' = 2.7; column 'kcat^b (s^-1)' = 40; column 'Specificity (kcat/Km)' = 14 (footnote b: L . s^-1 . umol^-1).

normalized_value_unit_evidence: Km: printed Table 3 cell 2.7 uM; 2.7 / 1000 = 0.0027 mM; the exported value is 0.003 mM. kcat: printed Table 3 cell 40 s^-1; already in s^-1, no conversion (this paper prints no min^-1 kinetic cell); the exported value is 40.0 s^(-1). kcat/Km: printed Table 3 Specificity cell 14 L . s^-1 . umol^-1; footnote b prints that unit literal and 1 L . s^-1 . umol^-1 is 1 s^-1 uM^-1, so 14 x 1000 = 14000.0 s^-1 mM^-1; the exported value is 13333.333333333334 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table 3 (journal page 318), substrate row 'Benzylpenicillin', enzyme column 'BRO-1p': Km = 2.7 uM; kcat = 40 s^-1; printed Specificity (kcat/Km) = 14 L . s^-1 . umol^-1.

row_label: Table 3, substrate row 'Benzylpenicillin', enzyme column 'BRO-1p' (Branhamella catarrhalis strain L14)


sequence_source: UniProtKB Q49095 unreviewed TrEMBL; direct lookup 2026-05-27

column_label: Table 3. Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method; row Methicillin; column group Km^a (uM), column BRO-2p: raw value 26 uM, normalized value 0.026 mM; column group kcat^b (s^-1), column BRO-2p: raw value 190 s^-1, normalized value 190 s^-1; column group Specificity (kcat/Km), column BRO-2p: the table prints 7.3 in units of 10^6 M^-1 s^-1, a two-significant-figure value that agrees with the quotient of this same row and column pair, so the absolute ratio recorded here is that quotient 190 / 0.026 = 7307.692307692308 s^-1 mM^-1.

normalized_value_unit_evidence: metric: kcat; raw value: 190; raw unit: s^-1; normalized value: 190; normalized unit: s^-1; metric: Km; raw value: 26; raw unit: uM; normalized value: 0.026; normalized unit: mM; metric: kcat/Km; the table prints only the rounded specificity column, so the absolute ratio recorded here is the quotient of this row's own two printed cells, paper kcat divided by paper Km; normalized value: 7307.692307692308; normalized unit: s^-1 mM^-1; assay condition: Purified papain-solubilized BRO-1p (strain L14) or BRO-2p (strain L16904) beta-lactamase; spectrophotometric progress curves analysed by the T1/2 method in 20 mM TEA-HCl / 0.15 M NaCl buffer, pH 7.0, at a constant temperature of 30 C.

raw_value_unit_evidence: Table 3. Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method (PDF page 6, journal page 318), row Methicillin: kcat^b (s^-1) column BRO-2p prints 190; Km^a (uM) column BRO-2p prints 26; Specificity (kcat/Km) column BRO-2p prints 7.3 in units of 10^6 M^-1 s^-1. Footnote a: Mean of three values.


column_label: Table 3: Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method. Substrate row 'Benzylpenicillin'; enzyme column 'BRO-2p'; column 'Km^a (uM)' = 2.9; column 'kcat^b (s^-1)' = 41; column 'Specificity (kcat/Km)' = 14 (footnote b: L . s^-1 . umol^-1).

normalized_value_unit_evidence: Km: printed Table 3 cell 2.9 uM; 2.9 / 1000 = 0.0029 mM; the exported value is 0.003 mM. kcat: printed Table 3 cell 41 s^-1; already in s^-1, no conversion (this paper prints no min^-1 kinetic cell); the exported value is 41.0 s^(-1). kcat/Km: printed Table 3 Specificity cell 14 L . s^-1 . umol^-1; footnote b prints that unit literal and 1 L . s^-1 . umol^-1 is 1 s^-1 uM^-1, so 14 x 1000 = 14000.0 s^-1 mM^-1; the exported value is 13666.666666666666 s^(-1)*mM^(-1).

raw_value_unit_evidence: Table 3 (journal page 318), substrate row 'Benzylpenicillin', enzyme column 'BRO-2p': Km = 2.9 uM; kcat = 41 s^-1; printed Specificity (kcat/Km) = 14 L . s^-1 . umol^-1.

row_label: Table 3, substrate row 'Benzylpenicillin', enzyme column 'BRO-2p' (Branhamella catarrhalis strain L16904)


substrate_name: Cefaclor

sequence_source: UniProtKB:Q59514; direct REST accession check on 2026-05-27

column_label: Table 3. Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method; row Cefaclor; column group Km^a (uM), column BRO-1p: raw value 34 uM, normalized value 0.034 mM; column group kcat^b (s^-1), column BRO-1p: raw value 65 s^-1, normalized value 65 s^-1; column group Specificity (kcat/Km), column BRO-1p: the table prints 1.9 in units of 10^6 M^-1 s^-1, a two-significant-figure value that agrees with the quotient of this same row and column pair, so the absolute ratio recorded here is that quotient 65 / 0.034 = 1911.7647058823527 s^-1 mM^-1.

normalized_value_unit_evidence: metric: kcat; raw value: 65; raw unit: s^-1; normalized value: 65; normalized unit: s^-1; metric: Km; raw value: 34; raw unit: uM; normalized value: 0.034; normalized unit: mM; metric: kcat/Km; the table prints only the rounded specificity column, so the absolute ratio recorded here is the quotient of this row's own two printed cells, paper kcat divided by paper Km; normalized value: 1911.7647058823527; normalized unit: s^-1 mM^-1; assay condition: Purified papain-solubilized BRO-1p (strain L14) or BRO-2p (strain L16904) beta-lactamase; spectrophotometric progress curves analysed by the T1/2 method in 20 mM TEA-HCl / 0.15 M NaCl buffer, pH 7.0, at a constant temperature of 30 C.

raw_value_unit_evidence: Table 3. Kinetic constants of the BRO-1p and BRO-2p beta-lactamases of Branhamella catarrhalis as determined spectrophotometrically using the T1/2 method (PDF page 6, journal page 318), row Cefaclor: kcat^b (s^-1) column BRO-1p prints 65; Km^a (uM) column BRO-1p prints 34; Specificity (kcat/Km) column BRO-1p prints 1.9 in units of 10^6 M^-1 s^-1. Footnote a: Mean of three values.

row_label: Cefaclor

substrate: Cefaclor