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Information on EC 1.1.1.382 - ketol-acid reductoisomerase (NAD+)
for references in articles please use BRENDA:EC1.1.1.382
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EC Tree 1 Oxidoreductases
1.1 Acting on the CH-OH group of donors
1.1.1 With NAD+ or NADP+ as acceptor
1.1.1.382 ketol-acid reductoisomerase (NAD+)
IUBMB Comments
The enzyme, characterized from the bacteria Thermacetogenium phaeum and Desulfococcus oleovorans and from the archaeon Archaeoglobus fulgidus, is specific for NADH [cf. EC 1.1.1.86, ketol-acid reductoisomerase (NADP+) and EC 1.1.1.383, ketol-acid reductoisomerase [NAD(P)+]].
The expected taxonomic range for this enzyme is: Bacteria, Archaea
Reaction Schemes
showSynonyms
ilvC, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
ilvC
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
(2R)-2,3-dihydroxy-3-methylbutanoate + NAD+ = (2S)-2-hydroxy-2-methyl-3-oxobutanoate + NADH + H+
-
-
-
-
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SYSTEMATIC NAME
IUBMB Comments
(2R)-2,3-dihydroxy-3-methylbutanoate:NAD+ oxidoreductase (isomerizing)
The enzyme, characterized from the bacteria Thermacetogenium phaeum and Desulfococcus oleovorans and from the archaeon Archaeoglobus fulgidus, is specific for NADH [cf. EC 1.1.1.86, ketol-acid reductoisomerase (NADP+) and EC 1.1.1.383, ketol-acid reductoisomerase [NAD(P)+]].
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
(2S)-2-hydroxy-2-methyl-3-oxobutanoate + NADH + H+
(2R)-2,3-dihydroxy-3-methylbutanoate + NAD+
(2S)-2-hydroxy-2-methyl-3-oxobutanoate + NADH + H+
(2R)-2,3-dihydroxy-3-methylbutanoate + NAD+
Substrates: (2S)-2-hydroxy-2-methyl-3-oxobutanoate i.e. (2S)-2-acetolactate
Products: -
Products: -
?
(2S)-2-hydroxy-2-methyl-3-oxobutanoate + NADH + H+
(2R)-2,3-dihydroxy-3-methylbutanoate + NAD+
-
Substrates: (2S)-2-hydroxy-2-methyl-3-oxobutanoate i.e. (2S)-2-acetolactate
Products: -
Products: -
?
(2S)-2-hydroxy-2-methyl-3-oxobutanoate + NADH + H+
(2R)-2,3-dihydroxy-3-methylbutanoate + NAD+
-
Substrates: (2S)-2-hydroxy-2-methyl-3-oxobutanoate i.e. (2S)-2-acetolactate
Products: -
Products: -
?
(2S)-2-hydroxy-2-methyl-3-oxobutanoate + NADH + H+
(2R)-2,3-dihydroxy-3-methylbutanoate + NAD+
-
Substrates: (2S)-2-hydroxy-2-methyl-3-oxobutanoate i.e. (2S)-2-acetolactate
Products: -
Products: -
?
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COFACTOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
additional information
NADH
-
Km-value for NADH is below 0.001 mM, pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
0.005
NADH
pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
0.032
NADH
-
pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
1.1
NADH
-
pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.1
NADH
pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
0.22
NADH
-
pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
0.25
NADH
-
pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
0.46
NADH
-
pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
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kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
additional information
NADH
-
kcat/Km for NADH is at least 460 /mM*s, pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
8
NADH
-
pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
20
NADH
pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
200
NADH
-
pH 7, temperature not specified in the publication, cosubstrate: (2S)-2-hydroxy-2-methyl-3-oxobutanoate
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
cf. EC 1.1.1.86
SwissProt
brenda
Highest Expressing Human Cell Lines
Cell Line LinksPlease wait a moment until the data is sorted. This message will disappear when the data is sorted.
UNIPROT
ENTRY NAME
ORGANISM
NO. OF AA
NO. OF TRANSM. HELICES
MOLECULAR WEIGHT[Da]
SOURCE
SEQUENCE
LOCALIZATION PREDICTION
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable).
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable). ILVC_DESOH
Desulfosudis oleivorans (strain DSM 6200 / JCM 39069 / Hxd3)
352
0
38685
Swiss-Prot
-
ILVC_THEPS
Thermacetogenium phaeum (strain ATCC BAA-254 / DSM 26808 / PB)
332
0
36963
Swiss-Prot
-
ILVC_ALIAD
Alicyclobacillus acidocaldarius subsp. acidocaldarius (strain ATCC 27009 / DSM 446 / BCRC 14685 / JCM 5260 / KCTC 1825 / NBRC 15652 / NCIMB 11725 / NRRL B-14509 / 104-IA)
344
0
37909
Swiss-Prot
Mitochondrion (Reliability: 4)
ILVC_IGNAA
Ignisphaera aggregans (strain DSM 17230 / JCM 13409 / AQ1.S1)
335
0
37346
Swiss-Prot
-
ILVC_ARCFU
Archaeoglobus fulgidus (strain ATCC 49558 / DSM 4304 / JCM 9628 / NBRC 100126 / VC-16)
332
0
37212
Swiss-Prot
-
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CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
in complex with substrate analog L-tartaric acid, to 2.5 A resolution. The enzyme displays a six-member specificity loop, with residues Arg48 and Ser52 forming hydrogen bonds to the NAD(H) phosphate
to 1.54 A resolution. Structure contains 2 Mg2+ ions and NADH. Glu46, the first residue of the beta2alphaB-loop, lies along the N3 edge of the adenine moiety and forms a bi-dentate interaction with the O2 hydroxy of the ribose. The position of this glutamate is stabilized by a hydrogen bond interaction with Asn55
apo-enzyme, to 1.39 A resolution, and in complex with NADP+. Enzyme accepts both cofactors NADH and NADPH. Insertions near the N-terminus of the specificity loop probably determine cofactor specificity, the laboratory engineering of NADH preference involved specific loop substitution
in complex with NADH, to 1.54 A resolution. The specificity loop differs significantly from any other crystallized ketol-acid reductoisomerases. Glu46, the first residue of the beta2alphaB-loop, lies along the N3 edge of the adenine moiety and forms a bi-dentate interaction with the O2' hydroxy of the ribose. The position of this glutamate is stabilized by a hydrogen bond interaction with Asn55
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
expression in Escherichia coli
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Cahn, J.K.; Brinkmann-Chen, S.; Spatzal, T.; Wiig, J.A.; Buller, A.R.; Einsle, O.; Hu, Y.; Ribbe, M.W.; Arnold, F.H.
Cofactor specificity motifs and the induced fit mechanism in Class I ketol-acid reductoisomerases
Biochem. J.
468
475-484
2015
Alicyclobacillus acidocaldarius subsp. acidocaldarius (C8WR67), Candidatus Methanophaga sp. ANME-1 ERB7 (Q64BR7), Ignisphaera aggregans (E0SRA9), Ignisphaera aggregans DSM 17230 (E0SRA9), uncultured archaeon (Q64BR7), uncultured archaeon GZfos26G2 (Q64BR7)
brenda
Brinkmann-Chen, S.; Cahn, J.K.; Arnold, F.H.
Uncovering rare NADH-preferring ketol-acid reductoisomerases
Metab. Eng.
26C
17-22
2014
Archaeoglobus fulgidus (O28294), Desulfosudis oleivorans, Thermacetogenium phaeum, uncultured archaeon
brenda
EXTERNAL LINKS (specific for EC-Number 1.1.1.382)
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