Any feedback?
Please rate this page
(literature.php)
(0/150)

BRENDA support

Literature summary for 2.3.3.13 extracted from

  • Kohlhaw, G.B.
    Alpha-isopropylmalate synthase from yeast (1988), Methods Enzymol., 166, 414-423.
    View publication on PubMed

Cloned(Commentary)

Cloned (Comment) Organism
-
Saccharomyces cerevisiae

Inhibitors

Inhibitors Comment Organism Structure
2-Oxo-isohexanoate competitive Saccharomyces cerevisiae
2-oxopentanoate competitive Saccharomyces cerevisiae
CoA Zn2+-dependent reversible inactivation Saccharomyces cerevisiae
leucine pH: 7.2, complete inhibition, pH: 8.0, 70% inhibition, pH: 8.8, 15% inhibition Saccharomyces cerevisiae

KM Value [mM]

KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
additional information
-
additional information
-
Saccharomyces cerevisiae
0.2
-
pyruvate
-
Saccharomyces cerevisiae
0.57
-
2-oxobutanoate
-
Saccharomyces cerevisiae

Localization

Localization Comment Organism GeneOntology No. Textmining
cytoplasm alpha-isopropylmalate synthase Ib Saccharomyces cerevisiae 5737
-
mitochondrion alpha-isopropylmalate synthase Ia, MW 68000, is imported into the mitochondrial matrix Saccharomyces cerevisiae 5739
-

Metals/Ions

Metals/Ions Comment Organism Structure
K+ enzyme requires the presence of monovalent cations, K+ is most effective Saccharomyces cerevisiae
Zinc enzyme of strain S288C contains 2 gatoms of zinc per subunit Saccharomyces cerevisiae

Molecular Weight [Da]

Molecular Weight [Da] Molecular Weight Maximum [Da] Comment Organism
68416
-
x * 68416, isoenzyme I, calculation from nucleotide sequence Saccharomyces cerevisiae

Natural Substrates/ Products (Substrates)

Natural Substrates Organism Comment (Nat. Sub.) Natural Products Comment (Nat. Pro.) Rev. Reac.
2-oxo-3-methylbutanoate + acetyl-CoA + H2O Saccharomyces cerevisiae first enzyme in biosynthesis of L-Leu ?
-
?

Organism

Organism UniProt Comment Textmining
Saccharomyces cerevisiae
-
3 enzyme forms, 1. alpha-isopropylmalate synthase I, isoenzyme encoded by LEU, subform Ia, MW 68000, which is imported into the mitochondrial matrix, and cytoplasmic synthase Ib, 2. alpha-isopropylmalate synthase II, minor enzyme form
-

Purification (Commentary)

Purification (Comment) Organism
-
Saccharomyces cerevisiae

Specific Activity [micromol/min/mg]

Specific Activity Minimum [µmol/min/mg] Specific Activity Maximum [µmol/min/mg] Comment Organism
7.1
-
-
Saccharomyces cerevisiae

Substrates and Products (Substrate)

Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
2-oxo-3-methylbutanoate + acetyl-CoA + H2O
-
Saccharomyces cerevisiae 3-hydroxy-4-methyl-3-carboxypentanoate + CoA i.e. alpha-isopropylmalate ?
2-oxo-3-methylbutanoate + acetyl-CoA + H2O first enzyme in biosynthesis of L-Leu Saccharomyces cerevisiae ?
-
?
2-oxo-butanoate + acetyl-CoA + H2O
-
Saccharomyces cerevisiae 2-ethyl-2-hydroxysuccinic acid + CoA
-
?
pyruvate + acetyl-CoA + H2O
-
Saccharomyces cerevisiae 2-hydroxy-2-methylsuccinic acid + CoA
-
?

Subunits

Subunits Comment Organism
? x * 68416, isoenzyme I, calculation from nucleotide sequence Saccharomyces cerevisiae
dimer 2 * 65000-68000 Saccharomyces cerevisiae

pH Optimum

pH Optimum Minimum pH Optimum Maximum Comment Organism
7.2 8.5
-
Saccharomyces cerevisiae

pH Stability

pH Stability pH Stability Maximum Comment Organism
7
-
activity of enzyme drops off rapidly below pH 7.0 Saccharomyces cerevisiae
7.2 8.2 activity of enzyme drops off rapidly above pH 9.0 Saccharomyces cerevisiae

Ki Value [mM]

Ki Value [mM] Ki Value maximum [mM] Inhibitor Comment Organism Structure
0.07
-
CoA interacting with the product site Saccharomyces cerevisiae
0.1
-
leucine only isoenzyme I activity Saccharomyces cerevisiae
0.2
-
leucine pH: 7.2, half-maximal inhibition Saccharomyces cerevisiae
1.2
-
leucine only isoenzyme II activity Saccharomyces cerevisiae