NIFH_TRIAZ
ID NIFH_TRIAZ Reviewed; 295 AA.
AC P0A3S2; O08050; Q43886;
DT 15-MAR-2005, integrated into UniProtKB/Swiss-Prot.
DT 15-MAR-2005, sequence version 1.
DT 03-AUG-2022, entry version 68.
DE RecName: Full=Nitrogenase iron protein;
DE EC=1.18.6.1;
DE AltName: Full=Nitrogenase Fe protein;
DE AltName: Full=Nitrogenase component II;
DE AltName: Full=Nitrogenase reductase;
GN Name=nifH;
OS Trichormus azollae (Anabaena azollae).
OC Bacteria; Cyanobacteria; Nostocales; Nostocaceae; Trichormus.
OX NCBI_TaxID=1164;
RN [1]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RC STRAIN=1a;
RX PubMed=7496536; DOI=10.1099/13500872-141-9-2235;
RA Jackman D.M., Mulligan M.E.;
RT "Characterization of a nitrogen-fixation (nif) gene cluster from Anabaena
RT azollae 1a shows that closely related cyanobacteria have highly variable
RT but structured intergenic regions.";
RL Microbiology 141:2235-2244(1995).
CC -!- FUNCTION: The key enzymatic reactions in nitrogen fixation are
CC catalyzed by the nitrogenase complex, which has 2 components: the iron
CC protein and the molybdenum-iron protein. {ECO:0000250}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=16 ATP + 16 H2O + N2 + 8 reduced [2Fe-2S]-[ferredoxin] = 16
CC ADP + 6 H(+) + H2 + 2 NH4(+) + 8 oxidized [2Fe-2S]-[ferredoxin] + 16
CC phosphate; Xref=Rhea:RHEA:21448, Rhea:RHEA-COMP:10000, Rhea:RHEA-
CC COMP:10001, ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:17997,
CC ChEBI:CHEBI:18276, ChEBI:CHEBI:28938, ChEBI:CHEBI:30616,
CC ChEBI:CHEBI:33737, ChEBI:CHEBI:33738, ChEBI:CHEBI:43474,
CC ChEBI:CHEBI:456216; EC=1.18.6.1;
CC -!- COFACTOR:
CC Name=[4Fe-4S] cluster; Xref=ChEBI:CHEBI:49883; Evidence={ECO:0000250};
CC Note=Binds 1 [4Fe-4S] cluster per dimer. {ECO:0000250};
CC -!- SUBUNIT: Homodimer. {ECO:0000250}.
CC -!- PTM: The reversible ADP-ribosylation of Arg-104 inactivates the
CC nitrogenase reductase and regulates nitrogenase activity.
CC {ECO:0000250}.
CC -!- SIMILARITY: Belongs to the NifH/BchL/ChlL family. {ECO:0000305}.
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DR EMBL; L34879; AAA87251.1; -; Genomic_DNA.
DR AlphaFoldDB; P0A3S2; -.
DR SMR; P0A3S2; -.
DR GO; GO:0051539; F:4 iron, 4 sulfur cluster binding; IEA:UniProtKB-KW.
DR GO; GO:0005524; F:ATP binding; IEA:UniProtKB-UniRule.
DR GO; GO:0018697; F:carbonyl sulfide nitrogenase activity; IEA:UniProtKB-EC.
DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR GO; GO:0016163; F:nitrogenase activity; IEA:UniProtKB-UniRule.
DR GO; GO:0009399; P:nitrogen fixation; IEA:UniProtKB-UniRule.
DR Gene3D; 3.40.50.300; -; 1.
DR HAMAP; MF_00533; NifH; 1.
DR InterPro; IPR030655; NifH/chlL_CS.
DR InterPro; IPR000392; NifH/frxC.
DR InterPro; IPR005977; Nitrogenase_Fe_NifH.
DR InterPro; IPR027417; P-loop_NTPase.
DR PANTHER; PTHR42864; PTHR42864; 1.
DR Pfam; PF00142; Fer4_NifH; 1.
DR PIRSF; PIRSF000363; Nitrogenase_iron; 1.
DR SUPFAM; SSF52540; SSF52540; 1.
DR TIGRFAMs; TIGR01287; nifH; 1.
DR PROSITE; PS00746; NIFH_FRXC_1; 1.
DR PROSITE; PS00692; NIFH_FRXC_2; 1.
DR PROSITE; PS51026; NIFH_FRXC_3; 1.
PE 3: Inferred from homology;
KW 4Fe-4S; ADP-ribosylation; ATP-binding; Iron; Iron-sulfur; Metal-binding;
KW Nitrogen fixation; Nucleotide-binding; Oxidoreductase.
FT CHAIN 1..295
FT /note="Nitrogenase iron protein"
FT /id="PRO_0000139479"
FT BINDING 13..20
FT /ligand="ATP"
FT /ligand_id="ChEBI:CHEBI:30616"
FT /evidence="ECO:0000255"
FT BINDING 101
FT /ligand="[4Fe-4S] cluster"
FT /ligand_id="ChEBI:CHEBI:49883"
FT /ligand_note="ligand shared between dimeric partners"
FT /evidence="ECO:0000250"
FT BINDING 135
FT /ligand="[4Fe-4S] cluster"
FT /ligand_id="ChEBI:CHEBI:49883"
FT /ligand_note="ligand shared between dimeric partners"
FT /evidence="ECO:0000250"
FT MOD_RES 104
FT /note="ADP-ribosylarginine; by dinitrogenase reductase ADP-
FT ribosyltransferase"
FT /evidence="ECO:0000250"
SQ SEQUENCE 295 AA; 32230 MW; FBF64A53D8A4EF84 CRC64;
MTDENIRQIA FYGKGGIGKS TTSQNTLAAM AEMGQRIMIV GCDPKADSTR LMLHAKAQTT
VLHLAAERGA VEDLELHEVM LTGFRGVRCV ESGGPEPGVG CAGRGIITAI NFLEENGAYQ
DLDFVSYDVL GDVVCGGFAM PIREGKAQEI YIVTSGEMMA MYAANNIARG ILKYAHSGGV
RLGGLICNSR KTDREAELIE NLAERLNTQM IHFVPRDNIV QHAELRRMTV NEYAPDSNQG
QEYRALAKKI INNDKLTIPT PIEMDELEAL LIEYGILDDD SKHAEIIGKP AEATK
