ID   ILVH_AQUAE              Reviewed;         192 AA.
AC   O67703;
DT   30-MAY-2000, integrated into UniProtKB/Swiss-Prot.
DT   01-AUG-1998, sequence version 1.
DT   03-AUG-2022, entry version 116.
DE   RecName: Full=Acetolactate synthase small subunit;
DE            EC=2.2.1.6;
DE   AltName: Full=Acetohydroxy-acid synthase small subunit;
DE            Short=AHAS;
DE            Short=ALS;
GN   Name=ilvH; OrderedLocusNames=aq_1851;
OS   Aquifex aeolicus (strain VF5).
OC   Bacteria; Aquificae; Aquificales; Aquificaceae; Aquifex.
OX   NCBI_TaxID=224324;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=VF5;
RX   PubMed=9537320; DOI=10.1038/32831;
RA   Deckert G., Warren P.V., Gaasterland T., Young W.G., Lenox A.L.,
RA   Graham D.E., Overbeek R., Snead M.A., Keller M., Aujay M., Huber R.,
RA   Feldman R.A., Short J.M., Olsen G.J., Swanson R.V.;
RT   "The complete genome of the hyperthermophilic bacterium Aquifex aeolicus.";
RL   Nature 392:353-358(1998).
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   -!- 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 acetolactate synthase small subunit family.
CC       {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; AE000657; AAC07662.1; -; Genomic_DNA.
DR   PIR; E70459; E70459.
DR   RefSeq; NP_214271.1; NC_000918.1.
DR   RefSeq; WP_010881207.1; NC_000918.1.
DR   AlphaFoldDB; O67703; -.
DR   SMR; O67703; -.
DR   STRING; 224324.aq_1851; -.
DR   EnsemblBacteria; AAC07662; AAC07662; aq_1851.
DR   KEGG; aae:aq_1851; -.
DR   PATRIC; fig|224324.8.peg.1429; -.
DR   eggNOG; COG0440; Bacteria.
DR   HOGENOM; CLU_055003_1_3_0; -.
DR   InParanoid; O67703; -.
DR   OMA; EPYGIKE; -.
DR   OrthoDB; 1500398at2; -.
DR   UniPathway; UPA00047; UER00055.
DR   UniPathway; UPA00049; UER00059.
DR   Proteomes; UP000000798; Chromosome.
DR   GO; GO:0005829; C:cytosol; IBA:GO_Central.
DR   GO; GO:0003984; F:acetolactate synthase activity; IBA:GO_Central.
DR   GO; GO:1990610; F:acetolactate synthase regulator activity; IEA:InterPro.
DR   GO; GO:0009097; P:isoleucine biosynthetic process; IBA:GO_Central.
DR   GO; GO:0009099; P:valine biosynthetic process; IBA:GO_Central.
DR   CDD; cd04878; ACT_AHAS; 1.
DR   Gene3D; 3.30.70.1150; -; 1.
DR   InterPro; IPR004789; Acetalactate_synth_ssu.
DR   InterPro; IPR027271; Acetolactate_synth/TF_NikR_C.
DR   InterPro; IPR019455; Acetolactate_synth_ssu_C.
DR   InterPro; IPR045865; ACT-like_dom_sf.
DR   InterPro; IPR002912; ACT_dom.
DR   InterPro; IPR039557; AHAS_ACT.
DR   PANTHER; PTHR30239; PTHR30239; 1.
DR   Pfam; PF01842; ACT; 1.
DR   Pfam; PF10369; ALS_ss_C; 1.
DR   SUPFAM; SSF55021; SSF55021; 2.
DR   TIGRFAMs; TIGR00119; acolac_sm; 1.
DR   PROSITE; PS51671; ACT; 1.
PE   3: Inferred from homology;
KW   Amino-acid biosynthesis; Branched-chain amino acid biosynthesis;
KW   Reference proteome; Transferase.
FT   CHAIN           1..192
FT                   /note="Acetolactate synthase small subunit"
FT                   /id="PRO_0000151405"
FT   DOMAIN          29..103
FT                   /note="ACT"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01007"
SQ   SEQUENCE   192 AA;  21706 MW;  9C6558F7B814A51B CRC64;
     MADTLGKSEL EVIKPQKREI RKGQVRKHII TVKVRNEMGV LARIATLIAG KGYNIEGLSV
     GETHEKGISR MTIEVIGDDI VIEQVVKQLR RLIDTLKVSD LTDVPHVERE LALIKVYTPS
     SRARDEVLRI TEIFRGKVVD VSPDTYTIEV TGDEDKINAM IELLKPFGIK EMARTGKVAM
     RREMSIKEEE NE