ID   NIFS_TRIAZ              Reviewed;         400 AA.
AC   Q43884;
DT   01-NOV-1997, integrated into UniProtKB/Swiss-Prot.
DT   01-NOV-1996, sequence version 1.
DT   03-AUG-2022, entry version 84.
DE   RecName: Full=Cysteine desulfurase {ECO:0000250|UniProtKB:P05341};
DE            EC=2.8.1.7 {ECO:0000250|UniProtKB:P05341};
DE   AltName: Full=Nitrogenase metalloclusters biosynthesis protein NifS {ECO:0000250|UniProtKB:P05341};
GN   Name=nifS {ECO:0000250|UniProtKB:P05341};
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: Catalyzes the removal of elemental sulfur atoms from cysteine
CC       to produce alanine. Seems to participate in the biosynthesis of the
CC       nitrogenase metalloclusters by providing the inorganic sulfur required
CC       for the Fe-S core formation. {ECO:0000250|UniProtKB:P05341}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=[sulfur carrier]-H + L-cysteine = [sulfur carrier]-SH + L-
CC         alanine; Xref=Rhea:RHEA:43892, Rhea:RHEA-COMP:14737, Rhea:RHEA-
CC         COMP:14739, ChEBI:CHEBI:29917, ChEBI:CHEBI:35235, ChEBI:CHEBI:57972,
CC         ChEBI:CHEBI:64428; EC=2.8.1.7;
CC         Evidence={ECO:0000250|UniProtKB:P05341};
CC   -!- COFACTOR:
CC       Name=pyridoxal 5'-phosphate; Xref=ChEBI:CHEBI:597326;
CC         Evidence={ECO:0000250|UniProtKB:P05341};
CC   -!- SUBUNIT: Homodimer. {ECO:0000250|UniProtKB:P05341}.
CC   -!- SIMILARITY: Belongs to the class-V pyridoxal-phosphate-dependent
CC       aminotransferase family. NifS/IscS subfamily. {ECO:0000305}.
CC   ---------------------------------------------------------------------------
CC   Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC   Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC   ---------------------------------------------------------------------------
DR   EMBL; L34879; AAA87249.1; -; Genomic_DNA.
DR   AlphaFoldDB; Q43884; -.
DR   SMR; Q43884; -.
DR   GO; GO:0031071; F:cysteine desulfurase 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:0030170; F:pyridoxal phosphate binding; IEA:InterPro.
DR   GO; GO:0006520; P:cellular amino acid metabolic process; IEA:InterPro.
DR   GO; GO:0009399; P:nitrogen fixation; IEA:UniProtKB-KW.
DR   Gene3D; 3.40.640.10; -; 1.
DR   Gene3D; 3.90.1150.10; -; 1.
DR   InterPro; IPR000192; Aminotrans_V_dom.
DR   InterPro; IPR020578; Aminotrans_V_PyrdxlP_BS.
DR   InterPro; IPR017772; Cys_deSase_NifS_bac/arc.
DR   InterPro; IPR016454; Cysteine_dSase.
DR   InterPro; IPR015424; PyrdxlP-dep_Trfase.
DR   InterPro; IPR015421; PyrdxlP-dep_Trfase_major.
DR   InterPro; IPR015422; PyrdxlP-dep_Trfase_small.
DR   Pfam; PF00266; Aminotran_5; 1.
DR   PIRSF; PIRSF005572; NifS; 1.
DR   SUPFAM; SSF53383; SSF53383; 1.
DR   TIGRFAMs; TIGR03402; FeS_nifS; 1.
DR   PROSITE; PS00595; AA_TRANSFER_CLASS_5; 1.
PE   3: Inferred from homology;
KW   Iron; Iron-sulfur; Metal-binding; Nitrogen fixation; Pyridoxal phosphate;
KW   Transferase.
FT   CHAIN           1..400
FT                   /note="Cysteine desulfurase"
FT                   /id="PRO_0000150246"
FT   ACT_SITE        324
FT                   /note="Cysteine persulfide intermediate"
FT                   /evidence="ECO:0000250|UniProtKB:P05341"
FT   BINDING         71..72
FT                   /ligand="pyridoxal 5'-phosphate"
FT                   /ligand_id="ChEBI:CHEBI:597326"
FT                   /evidence="ECO:0000250|UniProtKB:P0A6B9"
FT   BINDING         150
FT                   /ligand="pyridoxal 5'-phosphate"
FT                   /ligand_id="ChEBI:CHEBI:597326"
FT                   /evidence="ECO:0000250|UniProtKB:O29689"
FT   BINDING         178
FT                   /ligand="pyridoxal 5'-phosphate"
FT                   /ligand_id="ChEBI:CHEBI:597326"
FT                   /evidence="ECO:0000250|UniProtKB:P0A6B9"
FT   BINDING         198..200
FT                   /ligand="pyridoxal 5'-phosphate"
FT                   /ligand_id="ChEBI:CHEBI:597326"
FT                   /evidence="ECO:0000250|UniProtKB:P0A6B9"
FT   BINDING         236
FT                   /ligand="pyridoxal 5'-phosphate"
FT                   /ligand_id="ChEBI:CHEBI:597326"
FT                   /evidence="ECO:0000250|UniProtKB:P0A6B9"
FT   BINDING         324
FT                   /ligand="[2Fe-2S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:190135"
FT                   /note="via persulfide group"
FT                   /evidence="ECO:0000250|UniProtKB:O29689"
FT   MOD_RES         201
FT                   /note="N6-(pyridoxal phosphate)lysine"
FT                   /evidence="ECO:0000250|UniProtKB:P0A6B9"
SQ   SEQUENCE   400 AA;  43685 MW;  8DEF6B713C5C3A6E CRC64;
     MSVIYLDNNA TTKVDPEVVE AIMPYLTDYY GNPSSMHTFG GQLGKAVRTA REQVAALLGA
     DESEIVFTSC GTEGDNAAIR AALLAQPEKR HIITTQVEHP AVLNVCKQLE TQGYTVTYLS
     VNGHGQLDLD ELEASLTGNT ALVTIMYANN ETGTVFPIEE IGKRVKERGA IFHVDAVQAV
     GKIPLNMKTS TIDMLTISGH KIHAPKGIGA LYVRRGVRFR PLLIGGHQER GRRAGTENVP
     GIVGLGKAAE LELIHIETAI KKETRLRDRL EQTLLAKIPD CEVNGDVTQR LPNTTNIGFK
     YIEGEAILLS LNKYGICASS GSACTSGSLE PSHVLRAMGL PYTTLHGSIR FSLCRYTTEA
     QIDRVIEVMP EIVERLRALS PFKNDEAGWL QAQEQTLAHR