HydDB provides access to an accurate classifier for hydrogenase sequences and a curated database of hydrogenases by known type. The service is provided by the School of Biological Sciences, Monash University and the Bioinformatics Research Centre, Aarhus University.


If an e-mail address is provided, a mail will be sent when the job succeeds or fails.


To use the classifier to predict the type of one or more hydrogenases from sequence, either:

  • paste your FASTA-formatted protein sequences into the text area, or
  • upload a FASTA-formatted file with your protein sequences.

Press the "Submit" button to upload the sequences and begin the classification.

If you provided an e-mail address you will receive an e-mail when your job finishes or fails including a link to the results. You will also be able to download the results as a CSV file.

Only sequences encoding the catalytic subunits of hydrogenases will be classified, i.e. those binding the [NiFe]-centre (NiFe-hydrogenases), [FeFe]-centre (FeFe-hydrogenases), or [Fe]-centre (Fe-hydrogenases). Electron-transfer subunits, accessory proteins, and maturation factors cannot be classified by this service.


A job can at most run for 2 hours and atmost 4000 sequences can be submitted. This should be enough for about 2500 sequences to be classified. Results will be stored for 2 weeks. However, we recommend to download the results as they may be deleted due to the rare event of a power outage or server crash.


Jobs completed in total 478559
Sequences classified in total 23132129
Jobs completed in the last 24 hours 2
Sequences classified in the last 24 hours 1423