Acetolactate decarboxylase

acetolactate decarboxylase
Identifiers
EC no.	4.1.1.5
CAS no.	9025-02-9
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 / QuickGO
Search PMC articles PubMed articles NCBI proteins

The enzyme acetolactate decarboxylase (EC 4.1.1.5) catalyzes the chemical reaction

(S)-2-hydroxy-2-methyl-3-oxobutanoate ${\displaystyle \rightleftharpoons }$ (R)-2-acetoin + CO₂

Hence, this enzyme has one substrate, (S)-2-hydroxy-2-methyl-3-oxobutanoate, and two products, (R)-2-acetoin and CO₂. ^[1]

This enzyme belongs to the family of lyases, specifically the carboxy-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is (S)-2-hydroxy-2-methyl-3-oxobutanoate carboxy-lyase [(R)-2-acetoin-forming]. Other names in common use include alpha-acetolactate decarboxylase, and (S)-2-hydroxy-2-methyl-3-oxobutanoate carboxy-lyase. This enzyme participates in butanoate metabolism and c5-branched dibasic acid metabolism.

Structural studies

As of late 2007, only one structure has been solved for this class of enzymes, with the PDB accession code 1XV2.

References

1. Hill RK, Sawada S, Arfin SM (1979). "Stereochemistry of valine and isoleucine biosynthesis. IV Synthesis, configuration, and enzymatic specificity of alpha-acetolactate and alpha-aceto-alpha-hydroxybutyrate". Bioorg. Chem. 8 (2): 175–189. doi:10.1016/0045-2068(79)90003-8.

• Stormer FC (1967). "Isolation of crystalline pH 6 acetolactate-forming enzyme from Aerobacter aerogenes". J. Biol. Chem. 242 (8): 1756–9. PMID   6024768.