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

BRENDA support

Literature summary extracted from

  • Lee, M.; Lee, S.; Cho, J.; Ryu, S.; Koo, B.; Yoon, M.
    Role of a highly conserved and catalytically important glutamate-49 in the Enterococcus faecalis acetolactate synthase (2013), Bull. Korean Chem. Soc., 34, 669-672.
No PubMed abstract available

Cloned(Commentary)

EC Number Cloned (Comment) Organism
2.2.1.6 expressed in Escherichia coli BL21(DE3) cells Enterococcus faecalis
2.2.1.6 recombinant expression of wild-type and mutants enzymes in Escherichia coli strain BL21(DE3) Enterococcus faecalis

Protein Variants

EC Number Protein Variants Comment Organism
2.2.1.6 E49A site-directed mutagenesis, the mutant shows decreased activities and weakened thiamine diphosphate binding. The Km for substrate pyruvate is 22fold higher than that of the wild-type cALS. In addition, the E49A mutation also has a drastic effect on cofactor thiamine diphosphate activation. The half-saturating concentration (Kc) for thiamine diphosphate is 2000fold higher than that of wild-type cALS Enterococcus faecalis
2.2.1.6 E49A the mutation causes a 190fold reduction in affinity for thiamine diphosphate Enterococcus faecalis
2.2.1.6 E49D site-directed mutagenesis, the mutant exhibits normal substrate kinetics, with the Km for pyruvate equal to that of wild-type cALS Enterococcus faecalis
2.2.1.6 E49D the mutation causes a 150fold reduction in affinity for thiamine diphosphate Enterococcus faecalis
2.2.1.6 E49Q site-directed mutagenesis, the mutant shows decreased activities and weakened thiamine diphosphate binding, the Kc for ThDP that is 3600fold higher than that of wild-type cALS Enterococcus faecalis
2.2.1.6 E49Q the mutant causes a 170fold reduction in affinity for thiamine diphosphate shows 7% of wild type activity Enterococcus faecalis
2.2.1.6 additional information the aspartate substitution significantly affects the activation of thiamine diphosphate. The Kc for thiamine diphosphate is determined to be 280fold higher than that of wild-type cALS Enterococcus faecalis

KM Value [mM]

EC Number KM Value [mM] KM Value Maximum [mM] Substrate Comment Organism Structure
2.2.1.6 additional information
-
 additional information substrate and cofactor kinetics of wild-type and mutant enzymes, overview Enterococcus faecalis
2.2.1.6 1.37
-
 pyruvate wild type enzyme, pH and temperature not specified in the publication Enterococcus faecalis
2.2.1.6 1.37
-
 pyruvate recombinant wild-type enzyme, pH and temperature not specified in the publication Enterococcus faecalis
2.2.1.6 1.7
-
 pyruvate recombinant mutant E49D, pH and temperature not specified in the publication Enterococcus faecalis
2.2.1.6 1.7
-
 pyruvate mutant enzyme E49D, pH and temperature not specified in the publication Enterococcus faecalis
2.2.1.6 16.24
-
 pyruvate recombinant mutant E49Q, pH and temperature not specified in the publication Enterococcus faecalis
2.2.1.6 16.24
-
 pyruvate mutant enzyme E49Q, pH and temperature not specified in the publication Enterococcus faecalis
2.2.1.6 30.58
-
 pyruvate recombinant mutant E49A, pH and temperature not specified in the publication Enterococcus faecalis
2.2.1.6 30.58
-
 pyruvate mutant enzyme E49A, pH and temperature not specified in the publication Enterococcus faecalis

Metals/Ions

EC Number Metals/Ions Comment Organism Structure
2.2.1.6 Mg2+ required Enterococcus faecalis

Natural Substrates/ Products (Substrates)

EC Number Natural Substrates Organism Comment (Nat. Sub.) Natural Products Comment (Nat. Pro.) Rev. Reac.
2.2.1.6 2 pyruvate Enterococcus faecalis
-
 2-acetolactate + CO2
-
 ?

Organism

EC Number Organism UniProt Comment Textmining
2.2.1.6 Enterococcus faecalis
-
-
-

Purification (Commentary)

EC Number Purification (Comment) Organism
2.2.1.6
-
 Enterococcus faecalis
2.2.1.6 recombinant wild-type and mutants enzymes from Escherichia coli strain BL21(DE3) Enterococcus faecalis

Substrates and Products (Substrate)

EC Number Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
2.2.1.6 2 pyruvate
-
 Enterococcus faecalis 2-acetolactate + CO2
-
 ?

Synonyms

EC Number Synonyms Comment Organism
2.2.1.6 ALS
-
 Enterococcus faecalis

Cofactor

EC Number Cofactor Comment Organism Structure
2.2.1.6 FAD required Enterococcus faecalis
2.2.1.6 thiamine diphosphate dependent on Enterococcus faecalis

General Information

EC Number General Information Comment Organism
2.2.1.6 evolution two types of ALSs, anabolic acetohydroxyacid synthase (AHAS) and catabolic ALSs (cALS). The anabolic AHAS is primarily found in plants, fungi, and bacteria, is involved in the biosynthesis of branched-chain amino acids, and contains FAD, whereas the cALS is found only in some bacteria and is involved in the butanediol fermentation pathway. Both of the enzymes are thiamine diphosphate-dependent and require a divalent metal ion for catalytic activity. The catabolic ALS can be distinguished from anabolic AHAS by a low optimal pH of about pH 6.0, FAD-independent functionality, a genetic location within the butanediol operon, and lack of a regulatory subunit. In all of the crystal structures of ThDP-dependent enzymes determined to date, with the exception of glyoxylate carbo-ligase (GCL), a highly conerved glutamate residue is found at hydrogen-bonding distance from the N1' atom of the aminopyrimidine ring of the boundThDP and plays a key role in catalysis. In Enterococcus faecalis it is Glu49 Enterococcus faecalis