1ublL:59-552 1wulL:59-552 1h2aL:59-552 1ubtL:59-552 1wujL:59-552 1ubuL:59-552 1ubkL:59-552 1ubhL:59-552 1ubmL:59-552 1wukL:59-552 1wuhL:59-552 1wuiL:59-552 1uboL:59-552 1ubrL:59-552 1frfL:50-549 Hydrogenases are enzymes that catalyze the reversible activation of hydrogen and which occur widely in prokaryotes as well as in some eukaryotes.
There are various types of hydrogenases, but all of them seem to contain at least one iron-sulphur cluster.
The [NiFe] and [NiFeSe] hydrogenases are heterodimer that consist of a small subunit that contains a signal peptide and a large subunit.
All the known large subunits seem to be evolutionary related;[1] they contain two Cys-x-x-Cys motifs; one at their N-terminal end; the other at their C-terminal end.
[2] In the [NiFeSe] hydrogenases the first cysteine of the C-terminal motif is a selenocysteine which has experimentally been shown to be a nickel ligand.