[NiFe] Group 4i-hydrogenase

This entry was last updated at: Feb. 9, 2018, 6:24 a.m.

Properties

Group	[NiFe] Group 4: Respiratory H₂-evolving [NiFe] hydrogenases
Subgroup	[NiFe] Group 4i: Ferredoxin-coupled, Ehb-typ
Function	Forms supercomplex that couples H₂ oxidation to ferredoxin reduction by utilising the sodium-motive force. The reduced ferredoxin generated can be used anabolically to sustain biosynthetic reactions. While the reverse direction is energetically favourable, it is unclear whether it occurs physiologically.
Activity	H₂-uptake
Oxygen tolerance	O₂-sensitive
Localisation	Membrane-bound

Distribution

Ecosystem distribution	Methanogenic environments such as anoxic soils, marine sediments, and gastrointestinal tracts
Taxonomic distribution	Encoded in multiple methanogenic orders

Genetic Organisation

e.g. Methanothermobacter marburgensis (WP-013296415.1):

Architecture

Structures	None
Subunits	17
Subunit description	EhbN (hydrogenase large subunit) EhbM (hydrogenase small subunit) EhbL (iron-sulfur subunit) EhbK (polyferredoxin subunit) EhbO (NuoH-like transmembrane adaptor) EhbF (NuoL-like transmembrane adaptor) EhbABCDEGHIJ (transmembrane subunits) EhbPQ (conserved hypothetical subunits)
Catalytic site	[NiFe]-centre
FeS clusters	Proximal: 4Cys[4Fe4S] Medial: Absent Distal: Absent

Sequences in this class

NCBI Accession	Organism	Hydrogenase Class	Phylum	Order	Activity (Predicted)	Oxygen Tolerance (Predicted)	Subunits (Predicted)	Metal Centres (Predicted)	Accessory Subunits (Predicted)
WP_012794989.1	Methanocaldococcus fervens	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_013099747.1	Methanocaldococcus infernus	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_010870540.1	Methanocaldococcus jannaschii	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_012981217.1	Methanocaldococcus sp. FS406-22	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_004590220.1	Methanocaldococcus villosus	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_015732720.1	Methanocaldococcus vulcanius	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_011973026.1	Methanococcus aeolicus	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_012194251.1	Methanococcus maripaludis	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_011972283.1	Methanococcus vannielii	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_013180047.1	Methanococcus voltae	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_013866214.1	Methanothermococcus okinawensis	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_018154032.1	Methanothermococcus thermolithotrophicus	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_007044316.1	Methanotorris formicicus	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_013798188.1	Methanotorris igneus	[NiFe] Group 4i	Euryarchaeota	Methanococcales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_004029221.1	Methanobacterium formicicum	[NiFe] Group 4i	Euryarchaeota	Methanobacteriales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_013643876.1	Methanobacterium lacus	[NiFe] Group 4i	Euryarchaeota	Methanobacteriales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_013826680.1	Methanobacterium paludis	[NiFe] Group 4i	Euryarchaeota	Methanobacteriales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_023992909.1	Methanobacterium sp. MB1	[NiFe] Group 4i	Euryarchaeota	Methanobacteriales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_012956799.1	Methanobrevibacter ruminantium	[NiFe] Group 4i	Euryarchaeota	Methanobacteriales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_019262598.1	Methanobrevibacter smithii	[NiFe] Group 4i	Euryarchaeota	Methanobacteriales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_016359143.1	Methanobrevibacter sp. AbM4	[NiFe] Group 4i	Euryarchaeota	Methanobacteriales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_011407013.1	Methanosphaera stadtmanae	[NiFe] Group 4i	Euryarchaeota	Methanobacteriales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_013296415.1	Methanothermobacter marburgensis	[NiFe] Group 4i	Euryarchaeota	Methanobacteriales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals
WP_010876862.1	Methanothermobacter thermautotrophicus	[NiFe] Group 4i	Euryarchaeota	Methanobacteriales	Evolving	Sensitive	16	[NiFe]-centre, 1 x [4Fe4S] clusters	NuoH, NuoL, polyferredoxin, nine TM proteins, two hypotheticals

Literature

Genetics:

Søndergaard, D., Petersen, C.N.S., and Greening, C. (2017) HydDB: a web tool for hydrogenase classification and analysis. Sci. Rep. 6: 34212.
Tersteegen, A. and Hedderich, R. (1999) Methanobacterium thermoautotrophicum encodes two multisubunit membrane-bound [NiFe] hydrogenases. Eur. J. Biochem. 264: 930-943.

Physiology:

Major, T.A., Liu, Y., and Whitman, W.B. (2010) Characterization of energy-conserving hydrogenase B in Methanococcus maripaludis. J. Bacteriol. 192: 4022-4030.
Porat, I., Kim, W., Hendrickson, E.L., Xia, Q., Zhang, Y., Wang, T., Taub, F., Moore, B.C., Anderson, I.J., Hackett, M., and Leigh, J.A. (2006) Disruption of the operon encoding Ehb hydrogenase limits anabolic CO₂ assimilation in the archaeon Methanococcus maripaludis. J. Bacteriol. 188: 1373-1380.
Thauer, R.K., 2012. The Wolfe cycle comes full circle. Proc. Acad. Natl. Sci. USA 109: 15084-15085.
Thauer, R.K., Kaster, A.K., Seedorf, H., Buckel, W., and Hedderich, R. (2008) Methanogenic archaea: ecologically relevant differences in energy conservation. Nat. Rev. Microbiol. 6: 579-591.