Biology:Nickel-dependent hydrogenase

From HandWiki
Nickel-dependent hydrogenase
Identifiers
SymbolNiFeSe_Hases
PfamPF00374
InterProIPR001501
PROSITEPDOC00400
SCOP21frv / SCOPe / SUPFAM
TCDB3.D.7

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. They can be broadly divided into two groups: hydrogenases containing nickel and, in some cases, also selenium (the [NiFe] and [NiFeSe] hydrogenases) and those lacking nickel (the [Fe] hydrogenases).

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. These four cysteines are involved in the binding of nickel.[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.[3]

References

  1. "Cloning and sequencing of a putative Escherichia coli [NiFe hydrogenase-1 operon containing six open reading frames"]. J. Bacteriol. 172 (4): 1969–1977. 1990. doi:10.1128/jb.172.4.1969-1977.1990. PMID 2180913. 
  2. "Crystal structure of the nickel-iron hydrogenase from Desulfovibrio gigas". Nature 373 (6515): 580–587. 1995. doi:10.1038/373580a0. PMID 7854413. 
  3. "Evidence for selenocysteine coordination to the active site nickel in the [NiFeSehydrogenases from Desulfovibrio baculatus"]. Proc. Natl. Acad. Sci. U.S.A. 86 (1): 147–151. 1989. doi:10.1073/pnas.86.1.147. PMID 2521386. 
This article incorporates text from the public domain Pfam and InterPro: IPR001501