ID   ANFK_AZOVI              Reviewed;         462 AA.
AC   P16267;
DT   01-APR-1990, integrated into UniProtKB/Swiss-Prot.
DT   23-JAN-2007, sequence version 3.
DT   03-AUG-2022, entry version 90.
DE   RecName: Full=Nitrogenase iron-iron protein beta chain;
DE            EC=1.18.6.1;
DE   AltName: Full=Dinitrogenase 3 subunit beta;
DE   AltName: Full=Nitrogenase component I;
GN   Name=anfK;
OS   Azotobacter vinelandii.
OC   Bacteria; Proteobacteria; Gammaproteobacteria; Pseudomonadales;
OC   Pseudomonadaceae; Azotobacter.
OX   NCBI_TaxID=354;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX   PubMed=2644222; DOI=10.1128/jb.171.2.1075-1086.1989;
RA   Joerger R.D., Jacobson M.R., Premakumar R., Wolfinger E.D., Bishop P.E.;
RT   "Nucleotide sequence and mutational analysis of the structural genes
RT   (anfHDGK) for the second alternative nitrogenase from Azotobacter
RT   vinelandii.";
RL   J. Bacteriol. 171:1075-1086(1989).
RN   [2]
RP   PROTEIN SEQUENCE OF 2-7.
RC   STRAIN=RP306;
RX   PubMed=8392330; DOI=10.1042/bj2930101;
RA   Pau R.N., Eldridge M.E., Lowe D.J., Mitchenall L.A., Eady R.R.;
RT   "Molybdenum-independent nitrogenases of Azotobacter vinelandii: a
RT   functional species of alternative nitrogenase-3 isolated from a molybdenum-
RT   tolerant strain contains an iron-molybdenum cofactor.";
RL   Biochem. J. 293:101-107(1993).
CC   -!- FUNCTION: This iron-iron protein is part of the nitrogenase complex
CC       that catalyzes the key enzymatic reactions in nitrogen fixation. Other
CC       nitrogenase complexes utilize a molybdenum-iron protein or a vanadium-
CC       iron protein.
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=[8Fe-7S] cluster; Xref=ChEBI:CHEBI:21143; Evidence={ECO:0000250};
CC       Note=Binds 1 [8Fe-7S] cluster per heterodimer. {ECO:0000250};
CC   -!- SUBUNIT: Hexamer of two alpha, two beta, and two delta chains.
CC   -!- SIMILARITY: Belongs to the NifD/NifK/NifE/NifN family. {ECO:0000305}.
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DR   EMBL; M23528; AAA82511.1; -; Genomic_DNA.
DR   PIR; D32057; D32057.
DR   RefSeq; WP_012703359.1; NZ_FPKM01000001.1.
DR   AlphaFoldDB; P16267; -.
DR   SMR; P16267; -.
DR   OMA; VGFPTYD; -.
DR   BioCyc; MetaCyc:MON-16521; -.
DR   GO; GO:0005524; F:ATP binding; IEA:UniProtKB-KW.
DR   GO; GO:0018697; F:carbonyl sulfide nitrogenase activity; IEA:UniProtKB-EC.
DR   GO; GO:0051536; F:iron-sulfur cluster binding; IEA:UniProtKB-KW.
DR   GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR   GO; GO:0016163; F:nitrogenase activity; IEA:UniProtKB-EC.
DR   GO; GO:0009399; P:nitrogen fixation; IEA:UniProtKB-KW.
DR   InterPro; IPR000510; Nase/OxRdtase_comp1.
DR   InterPro; IPR000318; Nase_comp1_CS.
DR   InterPro; IPR014280; Nase_Fe-Fe_bsu.
DR   Pfam; PF00148; Oxidored_nitro; 1.
DR   TIGRFAMs; TIGR02931; anfK_nitrog; 1.
DR   PROSITE; PS00699; NITROGENASE_1_1; 1.
DR   PROSITE; PS00090; NITROGENASE_1_2; 1.
PE   1: Evidence at protein level;
KW   ATP-binding; Direct protein sequencing; Iron; Iron-sulfur; Metal-binding;
KW   Nitrogen fixation; Nucleotide-binding; Oxidoreductase.
FT   INIT_MET        1
FT                   /note="Removed"
FT                   /evidence="ECO:0000269|PubMed:8392330"
FT   CHAIN           2..462
FT                   /note="Nitrogenase iron-iron protein beta chain"
FT                   /id="PRO_0000153092"
FT   BINDING         20
FT                   /ligand="[8Fe-7S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:21143"
FT                   /ligand_note="ligand shared with alpha chain"
FT                   /evidence="ECO:0000250"
FT   BINDING         45
FT                   /ligand="[8Fe-7S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:21143"
FT                   /ligand_note="ligand shared with alpha chain"
FT                   /evidence="ECO:0000250"
FT   BINDING         104
FT                   /ligand="[8Fe-7S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:21143"
FT                   /ligand_note="ligand shared with alpha chain"
FT                   /evidence="ECO:0000250"
FT   BINDING         143
FT                   /ligand="[8Fe-7S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:21143"
FT                   /ligand_note="ligand shared with alpha chain"
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   462 AA;  51180 MW;  2E4DE6267094E3CC CRC64;
     MTCEVKEKGR VGTINPIFTC QPAGAQFVSI GIKDCIGIVH GGQGCVMFVR LIFSQHYKES
     FELASSSLHE DGAVFGACGR VEEAVDVLLS RYPDVKVVPI ITTCSTEIIG DDVDGVIKKL
     NEGLLKEKFP DREVHLIAMH TPSFVGSMIS GYDVAVRDVV RHFAKREAPN DKINLLTGWV
     NPGDVKELKH LLGEMDIEAN VLFEIESFDS PILPDGSAVS HGNTTIEDLI DTGNARATFA
     LNRYEGTKAA EYLQKKFEIP AIIGPTPIGI RNTDIFLQNL KKATGKPIPQ SLAHERGVAI
     DALADLTHMF LAEKRVAIYG APDLVIGLAE FCLDLEMKPV LLLLGDDNSK YVDDPRIKAL
     QENVDYGMEI VTNADFWELE NRIKNEGLEL DLILGHSKGR FISIDYNIPM LRVGFPTYDR
     AGLFRYPTVG YGGAIWLAEQ MANTLFADME HKKNKEWVLN VW