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Full data Every field, with sequences, SMILES and paper links JSON Lines (gzip) Table The table’s columns; no sequences, SMILES or paper links JSON Lines (gzip) Review files Source records and review notes, on request by email Dataset notes Fields, units, sources, licenses and how to cite

Filtered records: Export results, above the table.

CatLog enzyme kinetics records

Enzyme kcat, Km and kcat/Km values, being read from their papers. How it works →Loading CatLog snapshot

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CatLog in numbers

People behind CatLog

The loop runs clockwise from cited papers.

Using CatLog

Enzyme kcat, Km and kcat/Km values read from the original papers, mostly those the enzyme databases cite.

Chowdhury Lab, Iowa State University

Records and values

Enzyme Organism Substrate kcat s−1 Km mM kcat/Km mM−1 s−1 Review result 4-hydroxyacetophenone monooxygenase (HAPMO) Pseudomonas fluorescens 4‑aminoacetophenone 12.7 Acceptedfrom paper
One record, three values: Table 1, PMID 12514023.
Record
One row of Browse: one enzyme (wild type or variant), one substrate, one set of assay conditions, one paper.
Value
One number: a kcat, a Km or a kcat/Km. A record holds up to three.
Paper
One publication; a paper can give many records.

Review result

Accepted
Read from the paper by CatLog; or, for a record not yet re-read, accepted by the earlier automated review.
Not confirmed
The earlier review left a question open.
Not checked
No review result. The record says Unverified (no final check) or Not reviewed (no PMID or DOI).
Disputed
A check found a problem.

Tags

from paper
Read from the paper by CatLog’s current version (method).
not re-read
From CatLog’s earlier version, built from the enzyme databases; replaced when the paper is read.
human-checked
A human reviewer approved every value shown (a kcat/Km may instead agree with kcat ÷ Km).
earlier extraction
Read from a paper by CatLog’s earlier version.
corrected
Corrected by the earlier review; the record shows the change.
no paper linked
No PMID or DOI.

How CatLog works

How CatLog reads a value

  1. Read An AI model (Claude, Anthropic) reads each value with its unit, conditions and printed line, without seeing what the databases list.
  2. Check A second AI check compares each value with the paper; code confirms the printed line is in the paper.
  3. Compare Each value is compared with what the enzyme databases list for that paper.
  4. Review AI audits and people re-check samples for systematic errors; findings update the reading rules.

Units are converted by code, never by the model.

Records not yet re-read

Built from the enzyme databases by CatLog’s earlier version. Its automated review checked part of them against their papers.

Checks on Stats People behind CatLog

Read a record

4-hydroxyacetophenone monooxygenase (HAPMO)

EC 1.14.13.84 · Pseudomonas fluorescens · Wild type

Substrate: 4-aminoacetophenone

Acceptedhuman-checkedfrom paper

Values

Printed in Table 1
ParameterValueUnitAs printed
kcat12.7s−112.7 (0.7) s−1
KmmM0.82 (0.1) µM
kcat/KmmM−1 s−115,000 × 103 s−1·M−1

In the paper: “4-Aminoacetophenone 0.82 (0.1) 12.7 (0.7) 15,000”

Checks

Second check All values confirmed.

Human review Approved by a human reviewer.

ConditionsProtein and substratePaper

  1. Header Enzyme, EC number, organism, form and substrate.
  2. Review result The result and its tags (labels).
  3. Values In CatLog’s units, beside the cell as printed.
  4. In the paper The line the values come from.
  5. Checks The second AI check, AI audits and human review (How CatLog reads a value).
  6. Details Conditions, protein, substrate and paper.

Marks and cautions

Marks beside a value

A human reviewer approved this value.
A caution (Cautions).
calc.
kcat ÷ Km, calculated by CatLog.
—
No value (table cells only).

Cautions

What each beside a value means
Filter groupCautions
kcat/Km mismatch
  • kcat/Km mismatch (printed kcat/Km and kcat ÷ Km differ; all three kept; a factor near 60 points to minutes, near 1,000 to a concentration unit)
Unit or magnitude error

The unit or the value may be wrong.

  • Km > 10 M, Km < 1 nM
  • kcat > 108 s−1
  • possible 1000× unit error (in the kcat/Km concentration unit)
  • above diffusion limit (kcat/Km above 1010 M−1 s−1, 107 mM−1 s−1)
  • printed unit differs (from the concentration unit CatLog read)
No unit given
  • no unit
Temperature questionable
  • T questionable (exactly 0 °C may mean none was given)

Evidence labels

On records not yet re-read
Located in the paper
Where the paper prints the values; the text may be context, not this value.
Note from BRENDA
The database’s own note; no paper text.
Several database records
Merged from several database listings; no paper text.
Paper cited
The paper is linked; where it prints the values was not saved.
Database record only
Only the database record.

Usage notes

  • Only Accepted records passed review.
  • Read each value’s unit (Units).
  • A printed kcat/Km can differ from kcat ÷ Km (mismatch).
  • For training sets, split by paper or UniProt accession.

Reference

Find records

Search, filters and links
Search
An enzyme, EC number, organism, substrate, UniProt accession, PMID or DOI: laccase 1.10.3.2 P11509 12514023. A substrate word matches the start of a name part (lactose does not find galactose). Gene names are not indexed.
Filters
Enzyme, EC number, organism, substrate; parameter; review result.
More filters
Source, wild type or variant, assay conditions, cautions and source database.
Share
Every view and open record has its own address.

Try

Units

kcat s−1 · Km mM · kcat/Km mM−1 s−1
  • kcats−1Turnover number
  • KmmMMichaelis constant
  • kcat/KmmM−1 s−1Catalytic efficiency (× 1,000 for M−1 s−1)
× 10n
From 100,000, below 0.001, and from 1,000 when trailing zeros are not figures (3.5 × 104, not 35000).
Digits
Values read from the paper keep its significant figures; the downloads keep every stored digit.
T and pH
In the record and the downloads, not as table columns.
Other units
A few records not yet re-read keep another unit (min−1, mg/mL) or no unit.

Downloads

Full data, the table and the comparison
Full data
Every record and field, with sequences, SMILES and paper links.
Table
The table’s columns with pH and temperature; joins Full data on record_key.
Format
gzip JSON Lines, one record per line: pandas.read_json(path, lines=True, compression="gzip"). The Dataset notes list every field.
Review files
Behind records not yet re-read: request by email.
Pages
The records read from the paper, one page per paper and per EC number; about the data.
Download full data

Visits

What the site counts

The Visits page shows visits per day and by country. A visit ends after 30 minutes without a page view. A visitor is one browser and network per day, recognised by a code that changes daily and is deleted. No cookies. No addresses stored. Automated browsers and browsers that send Global Privacy Control are not counted. Cloudflare Web Analytics also measures page loads, without cookies.

License and citation

CatLog: CC BY 4.0. Database records keep their own license; quoted paper text remains the publisher’s.

Snapshot
—
Data ID
—
Cite

Sajeevan, K. A., et al. (2026). CatRange enables robust prediction of enzyme variant kinetic regimes. PNAS Nexus, pgag309. doi: 10.1093/pnasnexus/pgag309.

CatLog snapshot (date and data ID appear when the page loads)

More on citing

One value, the Data ID, CatLog-27k

For one value, add its record ID.

The Data ID is the first 10 characters of the SHA-256 of the decompressed Full data file (gunzip -c catlog-enriched.jsonl.gz | shasum -a 256).

CatLog grew out of CatLog-27k, the CatRange paper’s training set.

Sources and their licenses

Cite any database whose records you use
Read from the paper
CC BY 4.0
Earlier paper extractions
As published (see paper)
BRENDA
CC BY 4.0
SABIO-RK
See the source’s terms
SKiD
CC BY-NC-ND 4.0
UniProt
CC BY 4.0

For reuse of CatLog review notes and corrections, contact the Chowdhury Lab.

Questions

Why does a value differ from BRENDA?

BRENDA may use another unit, round the value or take it from another table, condition or enzyme form.

Why is a sequence or SMILES missing?

The enzyme matched no single UniProt entry, or the substrate no single structure (uniprot_candidate_ids lists the candidates).

How do I report an error?

Choose Report a problem in the record. For anything else, use Report a data issue.