P06661 (NIFH_THIFE) 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

Thiobacillus ferrooxidans (Acidithiobacillus ferrooxidans)

Taxonomic identifier

920 [NCBI]

Taxonomic lineage

cellular organisms › Bacteria › Proteobacteria › Gammaproteobacteria › Acidithiobacillales › Acidithiobacillaceae › Acidithiobacillus

Protein attributes

Sequence length	296 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 By similarity. HAMAP-Rule 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-Rule MF_00533
Cofactor	Binds 1 4Fe-4S cluster per dimer By similarity.
Subunit structure	Homodimer By similarity.
Post-translational modification	The reversible ADP-ribosylation of Arg-103 inactivates the nitrogenase reductase and regulates nitrogenase activity By similarity. HAMAP-Rule MF_00533
Sequence similarities	Belongs to the NifH/BchL/ChlL family.
Sequence caution	The sequence AAA27374.1 differs from that shown. Reason: Erroneous initiation.

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: HAMAP
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: HAMAP 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: HAMAP
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 296	296	Nitrogenase iron protein HAMAP-Rule MF_00533		PRO_0000139532
Regions
	Nucleotide binding	12 – 19	8	ATP Potential
Sites
	Metal binding	100	1	Iron-sulfur (4Fe-4S); shared with dimeric partner By similarity
	Metal binding	134	1	Iron-sulfur (4Fe-4S); shared with dimeric partner By similarity
Amino acid modifications
	Modified residue	103	1	ADP-ribosylarginine; by dinitrogenase reductase ADP-ribosyltransferase By similarity

Sequences

	Sequence		Length	Mass (Da)
	P06661 [UniParc]. Last modified January 23, 2002. Version 2. Checksum: CC8697F8CC9606EC	FASTA	296	31,823
	10 20 30 40 50 60 MSDKLRQIAF YGKGGIGKST TSQKHLAALA EMGQKILIVG CDPKADSTRL ILHSKAQDTV 70 80 90 100 110 120 LSLAAEAGSV EDLELEDVMK VGYRDIRCVE SGGPEPGVGC AGRGVITSIN FLEENGAYDG 130 140 150 160 170 180 ANYVSYDVLG DVVCGGFAMP IRKQAQEIYI VMSGEMMAMY AANNISKGVL KYANSGGVRL 190 200 210 220 230 240 GGLICNERQT DKELELAEAL AGKLGTKLIH FVPRDFIVQH AELRRMTVLE YAPESKQAQE 250 260 270 280 290 YRTLAEKIHA NAGNPAIPTP ITMDELEDLL MDFGIMQKED TSIIGKTAAE LAAAGM

References

[1]	"Nucleotide sequence of the gene encoding the nitrogenase iron protein of Thiobacillus ferrooxidans." Pretorius I.-M., Rawlings D.E., O'Neill E.G., Jones W.A., Kirby R., Woods D.R. J. Bacteriol. 169:367-370(1987) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].

Cross-references

Sequence databases
EMBL GenBank DDBJ	M15238 Genomic DNA. Translation: AAA27374.1. Different initiation.
PIR	A26931.
3D structure databases
ProteinModelPortal	P06661.
SMR	P06661. Positions 5-291.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Family and domain databases
HAMAP	MF_00533. NifH.
InterPro	IPR000392. Nitogenase_NifH/Reductase_ChlL. IPR005977. Nitrogenase_Fe_NifH. [Graphical view]
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_THIFE

Accession

Primary (citable) accession number: P06661

Entry history

Integrated into UniProtKB/Swiss-Prot:	January 1, 1988
Last sequence update:	January 23, 2002
Last modified:	April 3, 2013
This is version 90 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program