HAMAP

Accession	MF_00533
Dates	21-JAN-2002 (Created) 10-OCT-2011 (Last updated, Version 37)

Data class

Protein

Predictors

HAMAP; MF_00533; [distribution of match scores in UniProtKB];[seed alignment for MF_00533]

Names

NifH

Identifier

NIFH

Protein name

RecName: Full=Nitrogenase iron protein; EC=1.18.6.1; AltName: Full=Nitrogenase Fe protein; AltName: Full=Nitrogenase component II; AltName: Full=Nitrogenase reductase;

Gene name

nifH

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).

CATALYTIC ACTIVITY: 8 reduced ferredoxin + 8 H(+) + N(2) + 16 ATP + 16 H(2)O = 8 oxidized ferredoxin + H(2) + 2 NH(3) + 16 ADP + 16 phosphate.

COFACTOR: Binds 1 4Fe-4S cluster per dimer (By similarity).

SUBUNIT: Homodimer (By similarity).

PTM: The reversible ADP-ribosylation of #{Arg-101} inactivates the nitrogenase reductase and regulates nitrogenase activity (By similarity).

SIMILARITY: Belongs to the NifH/BchL/ChlL family.

Pfam	PF00142; Fer4_NifH; 1;
PIRSF	PIRSF000363; Nitrogenase_iron; 1;
PRINTS	PR00091; NITROGNASEII; 1;
TIGRFAMs	TIGR01287; NifH; 1;
PROSITE	PS00746; NIFH_FRXC_1; 1; PS00692; NIFH_FRXC_2; 1; PS51026; NIFH_FRXC_3; 1;

Oxidoreductase, Nitrogen fixation, Metal-binding, Iron, Iron-sulfur, 4Fe-4S, ATP-binding, Nucleotide-binding.

ADP-ribosylation.

GO:0005524; Molecular function: ATP binding.
GO:0016163; Molecular function: nitrogenase activity.
GO:0009399; Biological process: nitrogen fixation.
GO:0055114; Biological process: oxidation-reduction process.

From: NIFH1_AZOVI (P00459)
Key		From		To		Description		Condition		FTGroup
NP_BIND		10		17		ATP (Potential)		G-K-G-G-I-[GA]-K-S
METAL		98		98		Iron-sulfur (4Fe-4S); shared with dimeric partner (By similarity)		C
METAL		133		133		Iron-sulfur (4Fe-4S); shared with dimeric partner (By similarity)		C
MOD_RES		101		101		ADP-ribosylarginine; by dinitrogenase reductase ADP-ribosyltransferase (By similarity)		R

Size range:	263-307 amino acids
Related UniRules:	MF_00355 (BCHL)
Template:	P00459 (NIFH1_AZOVI); P00456 (NIFH1_CLOPA): [Recover all]
Scope:	Bacteria Archaea
Fusion:	Nter: None; Cter: None
Duplicate:	in NOSS1, ANAVA, AZOC5, AZOCH, CLOPA, MASLA, METBA, METIV, METTH, METTL, PAEAZ, RHOCA
Plasmid encoded:	in RHIET, RHIME, RHISN
Comments:	CYAA5 has a divergent nifH with a 37 N-terminal extension; this sequence is not shown in the alignment and not used for the size range