ID A0A0T7BMI8_9CYAN Unreviewed; 331 AA.
AC A0A0T7BMI8;
DT 17-FEB-2016, integrated into UniProtKB/TrEMBL.
DT 17-FEB-2016, sequence version 1.
DT 24-JAN-2024, entry version 42.
DE RecName: Full=Ketol-acid reductoisomerase (NADP(+)) {ECO:0000256|HAMAP-Rule:MF_00435};
DE Short=KARI {ECO:0000256|HAMAP-Rule:MF_00435};
DE EC=1.1.1.86 {ECO:0000256|HAMAP-Rule:MF_00435};
DE AltName: Full=Acetohydroxy-acid isomeroreductase {ECO:0000256|HAMAP-Rule:MF_00435};
DE Short=AHIR {ECO:0000256|HAMAP-Rule:MF_00435};
DE AltName: Full=Alpha-keto-beta-hydroxylacyl reductoisomerase {ECO:0000256|HAMAP-Rule:MF_00435};
GN Name=ilvC {ECO:0000256|HAMAP-Rule:MF_00435};
GN ORFNames=IJ00_02305 {ECO:0000313|EMBL:AKG20300.1};
OS Calothrix sp. 336/3.
OC Bacteria; Cyanobacteriota; Cyanophyceae; Nostocales; Calotrichaceae;
OC Calothrix.
OX NCBI_TaxID=1337936 {ECO:0000313|EMBL:AKG20300.1, ECO:0000313|Proteomes:UP000065745};
RN [1] {ECO:0000313|EMBL:AKG20300.1, ECO:0000313|Proteomes:UP000065745}
RP NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC STRAIN=336/3 {ECO:0000313|EMBL:AKG20300.1,
RC ECO:0000313|Proteomes:UP000065745};
RX PubMed=25614574;
RA Isojarvi J., Shunmugam S., Sivonen K., Allahverdiyeva Y., Aro E.M.,
RA Battchikova N.;
RT "Draft genome sequence of calothrix strain 336/3, a novel h2-producing
RT cyanobacterium isolated from a finnish lake.";
RL Genome Announc. 3:0-0(2015).
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:0000256|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:0000256|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:0000256|HAMAP-Rule:MF_00435};
CC -!- COFACTOR:
CC Name=Mg(2+); Xref=ChEBI:CHEBI:18420;
CC Evidence={ECO:0000256|HAMAP-Rule:MF_00435};
CC Note=Binds 2 magnesium ions per subunit. {ECO:0000256|HAMAP-
CC Rule:MF_00435};
CC -!- PATHWAY: Amino-acid biosynthesis; L-isoleucine biosynthesis; L-
CC isoleucine from 2-oxobutanoate: step 2/4.
CC {ECO:0000256|ARBA:ARBA00004885, ECO:0000256|HAMAP-Rule:MF_00435}.
CC -!- PATHWAY: Amino-acid biosynthesis; L-valine biosynthesis; L-valine from
CC pyruvate: step 2/4. {ECO:0000256|ARBA:ARBA00004864, ECO:0000256|HAMAP-
CC Rule:MF_00435}.
CC -!- SIMILARITY: Belongs to the ketol-acid reductoisomerase family.
CC {ECO:0000256|ARBA:ARBA00010318, ECO:0000256|HAMAP-Rule:MF_00435,
CC ECO:0000256|PROSITE-ProRule:PRU01198}.
CC -!- CAUTION: Lacks conserved residue(s) required for the propagation of
CC feature annotation. {ECO:0000256|HAMAP-Rule:MF_00435}.
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DR EMBL; CP011382; AKG20300.1; -; Genomic_DNA.
DR RefSeq; WP_035149661.1; NZ_CP011382.1.
DR AlphaFoldDB; A0A0T7BMI8; -.
DR STRING; 1337936.IJ00_02305; -.
DR KEGG; calh:IJ00_02305; -.
DR eggNOG; COG0059; Bacteria.
DR OrthoDB; 9804088at2; -.
DR UniPathway; UPA00047; UER00056.
DR UniPathway; UPA00049; UER00060.
DR Proteomes; UP000065745; Chromosome.
DR GO; GO:0016853; F:isomerase activity; IEA:UniProtKB-KW.
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; 2.
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 {ECO:0000256|ARBA:ARBA00022605, ECO:0000256|HAMAP-
KW Rule:MF_00435};
KW Branched-chain amino acid biosynthesis {ECO:0000256|ARBA:ARBA00023304,
KW ECO:0000256|HAMAP-Rule:MF_00435}; Isomerase {ECO:0000313|EMBL:AKG20300.1};
KW Magnesium {ECO:0000256|ARBA:ARBA00022842, ECO:0000256|HAMAP-Rule:MF_00435};
KW Metal-binding {ECO:0000256|ARBA:ARBA00022723, ECO:0000256|HAMAP-
KW Rule:MF_00435}; NADP {ECO:0000256|HAMAP-Rule:MF_00435};
KW Oxidoreductase {ECO:0000256|ARBA:ARBA00023002, ECO:0000256|HAMAP-
KW Rule:MF_00435}; Reference proteome {ECO:0000313|Proteomes:UP000065745}.
FT DOMAIN 2..182
FT /note="KARI N-terminal Rossmann"
FT /evidence="ECO:0000259|PROSITE:PS51850"
FT DOMAIN 183..328
FT /note="KARI C-terminal knotted"
FT /evidence="ECO:0000259|PROSITE:PS51851"
FT ACT_SITE 108
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435"
FT BINDING 25..28
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435"
FT BINDING 51
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435"
FT BINDING 53
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435"
FT BINDING 134
FT /ligand="NADP(+)"
FT /ligand_id="ChEBI:CHEBI:58349"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435"
FT BINDING 191
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435,
FT ECO:0000256|PROSITE-ProRule:PRU01198"
FT BINDING 191
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435,
FT ECO:0000256|PROSITE-ProRule:PRU01198"
FT BINDING 195
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="1"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435,
FT ECO:0000256|PROSITE-ProRule:PRU01198"
FT BINDING 227
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435,
FT ECO:0000256|PROSITE-ProRule:PRU01198"
FT BINDING 231
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /ligand_label="2"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435,
FT ECO:0000256|PROSITE-ProRule:PRU01198"
FT BINDING 252
FT /ligand="substrate"
FT /evidence="ECO:0000256|HAMAP-Rule:MF_00435,
FT ECO:0000256|PROSITE-ProRule:PRU01198"
SQ SEQUENCE 331 AA; 35805 MW; 89B3D09681158CDD CRC64;
MARMYYDSDA NLDLLTGKTI SIIGYGSQGH AHALNLKDSG LNVIVGLYPG SKSAAKAEAA
GLTVKNVADA AAAADMIMIL LPDEVQKTVY KTEIEPNLKP GNILAFAHGF NIHFGQVVPP
ADVDVVMVAP KGPGHLVRRT YEQGQGVPCL FAVYQDATGQ ARDRAMAYAK GVGGTRAGIL
ETTFREETET DLFGEQAVLC GGLSALIKAG FETLIEAGYQ PELAYFECLH EVKLIVDLVV
EGGLATMRDS ISNTAEYGDY TRGPRVVTEQ TKAEMKKILS EIQSGQFARE FVLENQSGKP
GFTAMRRQEA EHPIEEVGKD LRAMFSWLKK A
//
