Q51296 (NIFH_NOSS6) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Nitrogenase iron protein
EC=1.18.6.1

Alternative name(s):
Nitrogenase Fe protein
Nitrogenase component II
Nitrogenase reductase

Gene names

Name:

nifH

Organism

Nostoc sp. (strain PCC 6720) (Anabaenopsis circularis)

Taxonomic identifier

34077 [NCBI]

Taxonomic lineage

Bacteria › Cyanobacteria › Nostocales › Nostocaceae › Nostoc

Protein attributes

Sequence length	295 AA.
Sequence status	Complete.
Protein existence	Inferred from homology

General annotation (Comments)

Function	The key enzymatic reactions in nitrogen fixation are catalyzed by the nitrogenase complex, which has 2 components: the iron protein and the molybdenum-iron protein. HAMAP MF_00533
Catalytic activity	8 reduced ferredoxin + 8 H+ + N2 + 16 ATP + 16 H2O = 8 oxidized ferredoxin + H2 + 2 NH3 + 16 ADP + 16 phosphate. HAMAP MF_00533
Cofactor	Binds 1 4Fe-4S cluster per dimer.
Subunit structure	Homodimer By similarity. HAMAP MF_00533
Post-translational modification	The reversible ADP-ribosylation of Arg-104 inactivates the nitrogenase reductase and regulates nitrogenase activity By similarity. HAMAP MF_00533
Sequence similarities	Belongs to the NifH/BchL/ChlL family.

Ontologies

Keywords
Biological process	Nitrogen fixation
Ligand	4Fe-4S ATP-binding Iron Iron-sulfur Metal-binding Nucleotide-binding
Molecular function	Oxidoreductase
PTM	ADP-ribosylation
Gene Ontology (GO)
Biological process	nitrogen fixation Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	molybdenum-iron nitrogenase complex Inferred from electronic annotation. Source: InterPro
Molecular function	4 iron, 4 sulfur cluster binding Inferred from electronic annotation. Source: UniProtKB-KW ATP binding Inferred from electronic annotation. Source: UniProtKB-KW carbonyl sulfide nitrogenase activity Inferred from electronic annotation. Source: EC metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW nitrogenase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 295	295	Nitrogenase iron protein HAMAP MF_00533		PRO_0000139516
Regions
	Nucleotide binding	13 – 20	8	ATP Potential
Sites
	Metal binding	101	1	Iron-sulfur (4Fe-4S); shared with dimeric partner By similarity
	Metal binding	135	1	Iron-sulfur (4Fe-4S); shared with dimeric partner By similarity
Amino acid modifications
	Modified residue	104	1	ADP-ribosylarginine; by dinitrogenase reductase ADP-ribosyltransferase By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q51296 [UniParc]. Last modified November 1, 1996. Version 1. Checksum: 4A3A913E6E78A3E0	FASTA	295	32,230
	10 20 30 40 50 60 MTDENIRQIA FYGKGGIGKS TTSQNTLAAM AEMGQRIMIV GCDPKADSTR LMLHAKAKTT 70 80 90 100 110 120 VLHLAAERGA VEDLELHEVM LTGFRGVRCV ESGGPEPGVG CAGRGIITAI NFLEENGAYQ 130 140 150 160 170 180 DLDFVSYDVL GDVVCGGFAM PIREGKAQEI YIVTSGEMMA MYAANNIARG ILKYAHSGGV 190 200 210 220 230 240 RLGGLICNSR KTDREAELIE NLAERLNTQM IHFVPRDNIV QHAELRRMTV NEYAPDSNQG 250 260 270 280 290 QEYRALAKKI INNDKLTIPT PIEMDELEAL LIEYGILDDD SKHAEIIGKP AEATK

References

[1]	"Cloning and nucleotide sequence of the gene encoding dinitrogenase reductase (nifH) from the cyanobacterium Nostoc 6720." Beesley C.E., Smith R.J., Temple S.J., Lea P.J. Biochim. Biophys. Acta 1219:548-550(1994) [PubMed: 7918657] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	Z31716 Genomic DNA. Translation: CAA83510.1.
PIR	S50135.
3D structure databases
ProteinModelPortal	Q51296.
SMR	Q51296. Positions 6-292.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Family and domain databases
HAMAP	MF_00533. NifH. [Tree]
InterPro	IPR000392. Nitogenase_NifH/Reductase_ChlL. IPR005977. Nitrogenase_Fe_NifH. [Graphical view]
PANTHER	PTHR13696:SF32. PTHR13696:SF32. 1 hit.
Pfam	PF00142. Fer4_NifH. 1 hit. [Graphical view]
PIRSF	PIRSF000363. Nitrogenase_iron. 1 hit.
PRINTS	PR00091. NITROGNASEII.
TIGRFAMs	TIGR01287. NifH. 1 hit.
PROSITE	PS00746. NIFH_FRXC_1. 1 hit. PS00692. NIFH_FRXC_2. 1 hit. PS51026. NIFH_FRXC_3. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

NIFH_NOSS6

Accession

Primary (citable) accession number: Q51296

Entry history

Integrated into UniProtKB/Swiss-Prot:	January 23, 2002
Last sequence update:	November 1, 1996
Last modified:	October 19, 2011
This is version 74 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program