Reviewed, UniProtKB/Swiss-Prot P21950 (MBHS_AZOVI)

Names and origin

Protein names

Recommended name:
    Uptake hydrogenase small subunit
    EC=1.12.99.6
Alternative name(s):
    Hydrogenlyase
    Membrane-bound hydrogenase small subunit
    Hydrogenase subunit beta

Gene names

Name:

hoxK

Organism

Azotobacter vinelandii

Taxonomic identifier

354 [NCBI]

Taxonomic lineage

Bacteria › Proteobacteria › Gammaproteobacteria › Pseudomonadales › Pseudomonadaceae › Azotobacter

Protein attributes

Sequence length	358 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	This enzyme recycles the H2 produced by nitrogenase to increase the production of ATP and to protect nitrogenase against inhibition or damage by O2 under carbon- or phosphate-limited conditions.
Catalytic activity	H2 + A = AH2.
Cofactor	Binds 1 3Fe-4S cluster By similarity. Binds 2 4Fe-4S clusters By similarity.
Subunit structure	Heterodimer of a large and a small subunit.
Subcellular location	Cell membrane; Peripheral membrane protein.
Post-translational modification	Predicted to be exported by the Tat system. The position of the signal peptide cleavage has been experimentally proven.
Sequence similarities	Belongs to the [NiFe]/[NiFeSe] hydrogenase small subunit family.

Ontologies

Keywords
Cellular component	Cell membrane Membrane
Domain	Signal
Ligand	3Fe-4S 4Fe-4S Iron Iron-sulfur Metal-binding
Molecular function	Oxidoreductase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	oxidation reduction Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	ferredoxin hydrogenase complex Inferred from electronic annotation. Source: InterPro plasma membrane Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	3 iron, 4 sulfur cluster binding Inferred from electronic annotation. Source: UniProtKB-KW 4 iron, 4 sulfur cluster binding Inferred from electronic annotation. Source: UniProtKB-KW NADH dehydrogenase (ubiquinone) activity Inferred from electronic annotation. Source: InterPro ferredoxin hydrogenase activity Inferred from electronic annotation. Source: InterPro hydrogenase (acceptor) activity Inferred from electronic annotation. Source: EC iron ion binding Inferred from electronic annotation. Source: UniProtKB-KW quinone binding Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Signal peptide	1 – 45	45	Tat-type signal Ref.1
	Chain	46 – 358	313	Uptake hydrogenase small subunit		PRO_0000013424
Sites
	Metal binding	62	1	Iron-sulfur 1 (4Fe-4S) By similarity
	Metal binding	65	1	Iron-sulfur 1 (4Fe-4S) By similarity
	Metal binding	160	1	Iron-sulfur 1 (4Fe-4S) By similarity
	Metal binding	194	1	Iron-sulfur 1 (4Fe-4S) By similarity
	Metal binding	232	1	Iron-sulfur 2 (4Fe-4S); via pros nitrogen By similarity
	Metal binding	235	1	Iron-sulfur 2 (4Fe-4S) By similarity
	Metal binding	260	1	Iron-sulfur 2 (4Fe-4S) By similarity
	Metal binding	266	1	Iron-sulfur 2 (4Fe-4S) By similarity
	Metal binding	275	1	Iron-sulfur 3 (3Fe-4S) By similarity
	Metal binding	294	1	Iron-sulfur 3 (3Fe-4S) By similarity
	Metal binding	297	1	Iron-sulfur 3 (3Fe-4S) By similarity

Sequences

	Sequence		Length	Mass (Da)
	P21950-1 [UniParc]. Last modified May 1, 1991. Version 1. Checksum: BDCE5646D41D1C23	FASTA	358	39,259
	10 20 30 40 50 60 MSRLETFYDV MRRQGITRRS FLKYCSLTAA ALGLGPAFAP RIAHAMETKP RTPVLWLHGL 70 80 90 100 110 120 ECTCCSESFI RSAHPLVKDV VLSMISLDYD DTLMAAAGHQ AEAALEETMR KYKGEYILAV 130 140 150 160 170 180 EGNPPLNEDG MFCIVGGKPF IEQLRHVAKD AKAVIAWGSC ASWGCVQAAR PNPTQAVPIH 190 200 210 220 230 240 KVITDKPIVK VPGCPPIAEV MTGVITYMLT FGKLPELDRQ GRPKMFYGQR IHDKCYRRPH 250 260 270 280 290 300 FDAGQFVEHW DDEGARKGYC LYKVGCKGPT SYNACSTVRW NEGTSFPIQA GHGCIGCSED 310 320 330 340 350 GFWDKGSFYE RLTTIPQFGI EKNADEIGAA VAGGVGAAIA AHAAVTAIKR LQNKGDRP

References

[1]

"Cloning, sequencing and characterization of the [NiFe]hydrogenase-encoding structural genes (hoxK and hoxG) from Azotobacter vinelandii." Menon A.L., Stults L.W., Robson R.L., Mortenson L.E. Gene 96:67-74(1990) [PubMed: 2265761] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA], PROTEIN SEQUENCE OF 46-55. Strain: ATCC 13705 / OP1 / DSM 366 / NCIB 11614 / LMG 3878 / UW.

Cross-references

Sequence databases
EMBLGenBankDDBJ	M33152 Genomic DNA. Translation: AAA82505.1. L23970 Unassigned DNA. Translation: AAA19498.1.
PIR	JQ0805.
3D structure databases
HSSP	HSSP built from PDB template 1FRF based on UniProtKB P18187.
ModBase	Search...
Enzyme and pathway databases
BRENDA	1.12.99.6. 883.
Family and domain databases
InterPro	IPR006137. NADH_UbQ_OxRdtase-like_20kDa. IPR001821. NiFe_hydrogenase_ssu. IPR006311. Tat. IPR017909. Twin_arg_translocation_Tat. [Graphical view]
Pfam	PF01058. Oxidored_q6. 1 hit. [Graphical view]
PIRSF	PIRSF000310. NiFe_hyd_ssu. 1 hit.
PRINTS	PR00614. NIHGNASESMLL.
TIGRFAMs	TIGR00391. hydA. 1 hit. TIGR01409. TAT_signal_seq. 1 hit.
PROSITE	PS51318. TAT. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

MBHS_AZOVI

Accession

Primary (citable) accession number: P21950

Entry history

Integrated into UniProtKB/Swiss-Prot:	May 1, 1991
Last sequence update:	May 1, 1991
Last modified:	June 16, 2009
This is version 68 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HAMAP (High-quality Automated and Manual Annotation of microbial Proteomes)