ID ILVC_PROM1 Reviewed; 331 AA. AC A2C482; DT 15-JAN-2008, integrated into UniProtKB/Swiss-Prot. DT 20-FEB-2007, sequence version 1. DT 13-SEP-2023, entry version 96. DE RecName: Full=Ketol-acid reductoisomerase (NADP(+)) {ECO:0000255|HAMAP-Rule:MF_00435}; DE Short=KARI {ECO:0000255|HAMAP-Rule:MF_00435}; DE EC=1.1.1.86 {ECO:0000255|HAMAP-Rule:MF_00435}; DE AltName: Full=Acetohydroxy-acid isomeroreductase {ECO:0000255|HAMAP-Rule:MF_00435}; DE Short=AHIR {ECO:0000255|HAMAP-Rule:MF_00435}; DE AltName: Full=Alpha-keto-beta-hydroxylacyl reductoisomerase {ECO:0000255|HAMAP-Rule:MF_00435}; DE AltName: Full=Ketol-acid reductoisomerase type 1 {ECO:0000255|HAMAP-Rule:MF_00435}; DE AltName: Full=Ketol-acid reductoisomerase type I {ECO:0000255|HAMAP-Rule:MF_00435}; GN Name=ilvC {ECO:0000255|HAMAP-Rule:MF_00435}; OrderedLocusNames=NATL1_17361; OS Prochlorococcus marinus (strain NATL1A). OC Bacteria; Cyanobacteriota; Cyanophyceae; Synechococcales; OC Prochlorococcaceae; Prochlorococcus. OX NCBI_TaxID=167555; RN [1] RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. RC STRAIN=NATL1A; RX PubMed=18159947; DOI=10.1371/journal.pgen.0030231; RA Kettler G.C., Martiny A.C., Huang K., Zucker J., Coleman M.L., Rodrigue S., RA Chen F., Lapidus A., Ferriera S., Johnson J., Steglich C., Church G.M., RA Richardson P., Chisholm S.W.; RT "Patterns and implications of gene gain and loss in the evolution of RT Prochlorococcus."; RL PLoS Genet. 3:2515-2528(2007). CC -!- FUNCTION: Involved in the biosynthesis of branched-chain amino acids CC (BCAA). Catalyzes an alkyl-migration followed by a ketol-acid reduction CC of (S)-2-acetolactate (S2AL) to yield (R)-2,3-dihydroxy-isovalerate. In CC the isomerase reaction, S2AL is rearranged via a Mg-dependent methyl CC migration to produce 3-hydroxy-3-methyl-2-ketobutyrate (HMKB). In the CC reductase reaction, this 2-ketoacid undergoes a metal-dependent CC reduction by NADPH to yield (R)-2,3-dihydroxy-isovalerate. CC {ECO:0000255|HAMAP-Rule:MF_00435}. CC -!- CATALYTIC ACTIVITY: CC Reaction=(2R)-2,3-dihydroxy-3-methylbutanoate + NADP(+) = (2S)-2- CC acetolactate + H(+) + NADPH; Xref=Rhea:RHEA:22068, ChEBI:CHEBI:15378, CC ChEBI:CHEBI:49072, ChEBI:CHEBI:57783, ChEBI:CHEBI:58349, CC ChEBI:CHEBI:58476; EC=1.1.1.86; Evidence={ECO:0000255|HAMAP- CC Rule:MF_00435}; CC -!- CATALYTIC ACTIVITY: CC Reaction=(2R,3R)-2,3-dihydroxy-3-methylpentanoate + NADP(+) = (S)-2- CC ethyl-2-hydroxy-3-oxobutanoate + H(+) + NADPH; Xref=Rhea:RHEA:13493, CC ChEBI:CHEBI:15378, ChEBI:CHEBI:49256, ChEBI:CHEBI:49258, CC ChEBI:CHEBI:57783, ChEBI:CHEBI:58349; EC=1.1.1.86; CC Evidence={ECO:0000255|HAMAP-Rule:MF_00435}; CC -!- COFACTOR: CC Name=Mg(2+); Xref=ChEBI:CHEBI:18420; CC Evidence={ECO:0000255|HAMAP-Rule:MF_00435}; CC Note=Binds 2 magnesium ions per subunit. {ECO:0000255|HAMAP- CC Rule:MF_00435}; CC -!- PATHWAY: Amino-acid biosynthesis; L-isoleucine biosynthesis; L- CC isoleucine from 2-oxobutanoate: step 2/4. {ECO:0000255|HAMAP- CC Rule:MF_00435}. CC -!- PATHWAY: Amino-acid biosynthesis; L-valine biosynthesis; L-valine from CC pyruvate: step 2/4. {ECO:0000255|HAMAP-Rule:MF_00435}. CC -!- SIMILARITY: Belongs to the ketol-acid reductoisomerase family. CC {ECO:0000255|HAMAP-Rule:MF_00435}. 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; CP000553; ABM76292.1; -; Genomic_DNA. DR RefSeq; WP_011824291.1; NC_008819.1. DR AlphaFoldDB; A2C482; -. DR SMR; A2C482; -. DR STRING; 167555.NATL1_17361; -. DR EnsemblBacteria; ABM76292; ABM76292; NATL1_17361. DR KEGG; pme:NATL1_17361; -. DR eggNOG; COG0059; Bacteria. DR HOGENOM; CLU_033821_0_1_3; -. DR OMA; RAMFSWL; -. DR UniPathway; UPA00047; UER00056. DR UniPathway; UPA00049; UER00060. DR Proteomes; UP000002592; Chromosome. DR GO; GO:0004455; F:ketol-acid reductoisomerase activity; IEA:UniProtKB-UniRule. DR GO; GO:0000287; F:magnesium ion binding; IEA:UniProtKB-UniRule. DR GO; GO:0050661; F:NADP binding; IEA:InterPro. DR GO; GO:0009097; P:isoleucine biosynthetic process; IEA:UniProtKB-UniRule. DR GO; GO:0009099; P:valine biosynthetic process; IEA:UniProtKB-UniRule. DR Gene3D; 6.10.240.10; -; 1. DR Gene3D; 3.40.50.720; NAD(P)-binding Rossmann-like Domain; 1. DR HAMAP; MF_00435; IlvC; 1. DR InterPro; IPR008927; 6-PGluconate_DH-like_C_sf. DR InterPro; IPR013023; KARI. DR InterPro; IPR000506; KARI_C. DR InterPro; IPR013116; KARI_N. DR InterPro; IPR014359; KARI_prok. DR InterPro; IPR036291; NAD(P)-bd_dom_sf. DR NCBIfam; TIGR00465; ilvC; 1. DR PANTHER; PTHR21371; KETOL-ACID REDUCTOISOMERASE, MITOCHONDRIAL; 1. DR PANTHER; PTHR21371:SF1; KETOL-ACID REDUCTOISOMERASE, MITOCHONDRIAL; 1. DR Pfam; PF01450; IlvC; 1. DR Pfam; PF07991; IlvN; 1. DR PIRSF; PIRSF000116; IlvC_gammaproteo; 1. DR SUPFAM; SSF48179; 6-phosphogluconate dehydrogenase C-terminal domain-like; 1. DR SUPFAM; SSF51735; NAD(P)-binding Rossmann-fold domains; 1. DR PROSITE; PS51851; KARI_C; 1. DR PROSITE; PS51850; KARI_N; 1. PE 3: Inferred from homology; KW Amino-acid biosynthesis; Branched-chain amino acid biosynthesis; Magnesium; KW Metal-binding; NADP; Oxidoreductase. FT CHAIN 1..331 FT /note="Ketol-acid reductoisomerase (NADP(+))" FT /id="PRO_1000050554" FT DOMAIN 2..182 FT /note="KARI N-terminal Rossmann" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01197" FT DOMAIN 183..328 FT /note="KARI C-terminal knotted" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01198" FT ACT_SITE 108 FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 25..28 FT /ligand="NADP(+)" FT /ligand_id="ChEBI:CHEBI:58349" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 51 FT /ligand="NADP(+)" FT /ligand_id="ChEBI:CHEBI:58349" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 53 FT /ligand="NADP(+)" FT /ligand_id="ChEBI:CHEBI:58349" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 83..86 FT /ligand="NADP(+)" FT /ligand_id="ChEBI:CHEBI:58349" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 134 FT /ligand="NADP(+)" FT /ligand_id="ChEBI:CHEBI:58349" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 191 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /ligand_label="1" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 191 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /ligand_label="2" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 195 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /ligand_label="1" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 227 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /ligand_label="2" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 231 FT /ligand="Mg(2+)" FT /ligand_id="ChEBI:CHEBI:18420" FT /ligand_label="2" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" FT BINDING 252 FT /ligand="substrate" FT /evidence="ECO:0000255|HAMAP-Rule:MF_00435" SQ SEQUENCE 331 AA; 36262 MW; E620EF4B1395C3DD CRC64; MAKLFYDSDA DLGLLQDKTV AIIGYGSQGH AHALNLKDSG IKVVVGLYEG SRSASKAKSD GLEVLSVAEA SERADWIMIL LPDEFQKDVY SKEIAPHLKA GKILSFAHGF NIRFELIKPP EFVDVVMIAP KGPGHTVRWE YQNGQGVPAL FAIEQDASGN ARALAMAYAK GIGGTRAGIL ETNFKEETET DLFGEQAVLC GGLSELVKAG FETLVEAGYQ PELAYFECLH EVKLIVDLMV KGGLTAMRDS ISNTAEYGDY VSGPRLITKE TKEEMKNILA DIQDGTFAKN FVKECDAGKP EMKRIRQKDS ELPIEKVGKT LRSMFSWLKS D //