Dihydroxy-acid dehydratase

Dihydroxy-acid dehydratase
dihydroxy-acid dehydratase
Identifiers
EC number 4.2.1.9
CAS number 9024-32-2
Databases
IntEnz IntEnz view
BRENDA BRENDA entry
ExPASy NiceZyme view
KEGG KEGG entry
MetaCyc metabolic pathway
PRIAM profile
PDB structures RCSB PDB PDBe PDBsum
Gene Ontology AmiGO / EGO

In enzymology, a dihydroxy-acid dehydratase (EC 4.2.1.9) is an enzyme that catalyzes the chemical reaction

2,3-dihydroxy-3-methylbutanoate \rightleftharpoons 3-methyl-2-oxobutanoate + H2O

Hence, this enzyme has one substrate, 2,3-dihydroxy-3-methylbutanoate, and two products, 3-methyl-2-oxobutanoate and H2O.

This enzyme belongs to the family of lyases, specifically the hydro-lyases, which cleave carbon-oxygen bonds. The systematic name of this enzyme class is 2,3-dihydroxy-3-methylbutanoate hydro-lyase (3-methyl-2-oxobutanoate-forming). Other names in common use include acetohydroxyacid dehydratase, alpha,beta-dihydroxyacid dehydratase, 2,3-dihydroxyisovalerate dehydratase, alpha,beta-dihydroxyisovalerate dehydratase, dihydroxy acid dehydrase, DHAD, and 2,3-dihydroxy-acid hydro-lyase. This enzyme participates in valine, leucine and isoleucine biosynthesis and pantothenate and coa biosynthesis.

References

  • KANAMORI M, WIXOM RL (1963). "Studies in valine biosynthesis. V. Characteristics of the purified dihydroxyacid dehydratase from spinach leaves". J. Biol. Chem. 238: 998–1005. PMID 14030545. 
  • MYERS JW (1961). "Dihydroxy acid dehydrase: an enzyme involved in the biosynthesis of isoleucine and valine". J. Biol. Chem. 236: 1414–8. PMID 13727223.