ID   ILVB_METAO              Reviewed;         599 AA.
AC   O08353;
DT   16-AUG-2005, integrated into UniProtKB/Swiss-Prot.
DT   01-JUL-1997, sequence version 1.
DT   03-AUG-2022, entry version 87.
DE   RecName: Full=Probable acetolactate synthase large subunit;
DE            Short=AHAS;
DE            EC=2.2.1.6;
DE   AltName: Full=Acetohydroxy-acid synthase large subunit;
DE            Short=ALS;
GN   Name=ilvB;
OS   Methanococcus aeolicus.
OC   Archaea; Euryarchaeota; Methanomada group; Methanococci; Methanococcales;
OC   Methanococcaceae; Methanococcus.
OX   NCBI_TaxID=42879;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX   PubMed=9099862; DOI=10.1016/s0378-1119(96)00779-2;
RA   Bowen T.L., Union J., Tumbula D.L., Whitman W.B.;
RT   "Cloning and phylogenetic analysis of the genes encoding acetohydroxyacid
RT   synthase from the archaeon Methanococcus aeolicus.";
RL   Gene 188:77-84(1997).
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=H(+) + 2 pyruvate = (2S)-2-acetolactate + CO2;
CC         Xref=Rhea:RHEA:25249, ChEBI:CHEBI:15361, ChEBI:CHEBI:15378,
CC         ChEBI:CHEBI:16526, ChEBI:CHEBI:58476; EC=2.2.1.6;
CC   -!- COFACTOR:
CC       Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000250};
CC       Note=Binds 1 Mg(2+) ion per subunit. {ECO:0000250};
CC   -!- COFACTOR:
CC       Name=thiamine diphosphate; Xref=ChEBI:CHEBI:58937;
CC         Evidence={ECO:0000250};
CC       Note=Binds 1 thiamine pyrophosphate per subunit. {ECO:0000250};
CC   -!- PATHWAY: Amino-acid biosynthesis; L-isoleucine biosynthesis; L-
CC       isoleucine from 2-oxobutanoate: step 1/4.
CC   -!- PATHWAY: Amino-acid biosynthesis; L-valine biosynthesis; L-valine from
CC       pyruvate: step 1/4.
CC   -!- SUBUNIT: Dimer of large and small chains. {ECO:0000250}.
CC   -!- SIMILARITY: Belongs to the TPP enzyme family. {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; U35458; AAB53488.1; -; Genomic_DNA.
DR   AlphaFoldDB; O08353; -.
DR   SMR; O08353; -.
DR   BioCyc; MetaCyc:MON-11900; -.
DR   UniPathway; UPA00047; UER00055.
DR   UniPathway; UPA00049; UER00059.
DR   GO; GO:0003984; F:acetolactate synthase activity; IEA:UniProtKB-EC.
DR   GO; GO:0050660; F:flavin adenine dinucleotide binding; IEA:InterPro.
DR   GO; GO:0000287; F:magnesium ion binding; IEA:InterPro.
DR   GO; GO:0030976; F:thiamine pyrophosphate binding; IEA:InterPro.
DR   GO; GO:0009097; P:isoleucine biosynthetic process; IEA:UniProtKB-UniPathway.
DR   GO; GO:0044272; P:sulfur compound biosynthetic process; IEA:UniProt.
DR   GO; GO:0009099; P:valine biosynthetic process; IEA:UniProtKB-UniPathway.
DR   CDD; cd02015; TPP_AHAS; 1.
DR   InterPro; IPR012846; Acetolactate_synth_lsu.
DR   InterPro; IPR039368; AHAS_TPP.
DR   InterPro; IPR029035; DHS-like_NAD/FAD-binding_dom.
DR   InterPro; IPR029061; THDP-binding.
DR   InterPro; IPR012000; Thiamin_PyroP_enz_cen_dom.
DR   InterPro; IPR012001; Thiamin_PyroP_enz_TPP-bd_dom.
DR   InterPro; IPR000399; TPP-bd_CS.
DR   InterPro; IPR045229; TPP_enz.
DR   InterPro; IPR011766; TPP_enzyme-bd_C.
DR   PANTHER; PTHR18968; PTHR18968; 1.
DR   Pfam; PF02775; TPP_enzyme_C; 1.
DR   Pfam; PF00205; TPP_enzyme_M; 1.
DR   Pfam; PF02776; TPP_enzyme_N; 1.
DR   SUPFAM; SSF52467; SSF52467; 1.
DR   SUPFAM; SSF52518; SSF52518; 2.
DR   TIGRFAMs; TIGR00118; acolac_lg; 1.
DR   PROSITE; PS00187; TPP_ENZYMES; 1.
PE   3: Inferred from homology;
KW   Amino-acid biosynthesis; Branched-chain amino acid biosynthesis; FAD;
KW   Flavoprotein; Magnesium; Metal-binding; Thiamine pyrophosphate;
KW   Transferase.
FT   CHAIN           1..599
FT                   /note="Probable acetolactate synthase large subunit"
FT                   /id="PRO_0000090807"
FT   REGION          404..484
FT                   /note="Thiamine pyrophosphate binding"
FT   BINDING         47
FT                   /ligand="thiamine diphosphate"
FT                   /ligand_id="ChEBI:CHEBI:58937"
FT                   /evidence="ECO:0000250"
FT   BINDING         149
FT                   /ligand="FAD"
FT                   /ligand_id="ChEBI:CHEBI:57692"
FT                   /evidence="ECO:0000250"
FT   BINDING         258..279
FT                   /ligand="FAD"
FT                   /ligand_id="ChEBI:CHEBI:57692"
FT                   /evidence="ECO:0000250"
FT   BINDING         301..320
FT                   /ligand="FAD"
FT                   /ligand_id="ChEBI:CHEBI:57692"
FT                   /evidence="ECO:0000250"
FT   BINDING         455
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /evidence="ECO:0000250"
FT   BINDING         482
FT                   /ligand="Mg(2+)"
FT                   /ligand_id="ChEBI:CHEBI:18420"
FT                   /evidence="ECO:0000250"
SQ   SEQUENCE   599 AA;  65424 MW;  59630C57DECE0D62 CRC64;
     MNGAEAMIKA LEAEKVEILF GYPGGALLPF YDALHHSDLI HLLTRHEQAA AHAADGYARA
     SGKVGVCIGT SGPGATNLVT GVATAHSDSS PMVALTGQVP TKLIGNDAFQ EIDALGLFMP
     IVKHNFQIQK TCQIPEIFRS AFEIAQTGRP GPVHIDLPKD VQELELDIDK HPIPSKVKLI
     GYNPTTIGHP RQIKKAIKLI ASAKRPIILA GGGVLLSGAN EELLKLVELL NIPVCTTLMG
     KGCISENHPL ALGMVGMHGT KPANYCLSES DVLISIGCRF SDRITGDIKS FATNAKIIHI
     DIDPAEIGKN VNVDVPIVGD AKLILKEVIK QLDYIINKDS KENNDKENIS QWIENVNSLK
     KSSIPVMDYD DIPIKPQKIV KELMAVIDDL NINKNTIITT DVGQNQMWMA HYFKTQTPRS
     FLSSGGLGTM GFGFPSAIGA KVAKPDSKVI CITGDGGFMM NCQELGTIAE YNIPVVICIF
     DNRTLGMVYQ WQNLFYGKRQ CSVNFGGAPD FIKLAESYGI KARRIESPNE INEALKEAIN
     CDEPYLLDFA IDPSSALSMV PPGAKLTNII DAVQEHPNEK IVCFDEIKRR YMENKRNRK