The

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecule ...

acetolactate decarboxylase ()

catalyzes Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycl ...

the

chemical reaction A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and break ...

:(S)-2-hydroxy-2-methyl-3-oxobutanoate

\rightleftharpoons

(R)-2-acetoin + CO₂ Hence, this enzyme has one

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (locomotion), the surface over which an organism lo ...

, (S)-2-hydroxy-2-methyl-3-oxobutanoate, and two products, (R)-2-acetoin and CO₂. This enzyme belongs to the family of

lyase In biochemistry, a lyase is an enzyme that catalyzes the breaking (an elimination reaction) of various chemical bond A chemical bond is a lasting attraction between atoms or ions that enables the formation of molecules and crystals. The bon ...

s, specifically the carboxy-lyases, which cleave carbon-carbon bonds. The

systematic name A systematic name is a name given in a systematic way to one unique group, organism, object or chemical substance, out of a specific population or collection. Systematic names are usually part of a nomenclature. A semisystematic name or semitrivial ...

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 Butyric acid (; from grc, βούτῡρον, meaning "butter"), also known under the systematic name butanoic acid, is a straight-chain alkyl carboxylic acid with the chemical formula CH3CH2CH2CO2H. It is an oily, colorless liquid with an unple ...

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 .

References

* EC 4.1.1 Enzymes of known structure {{4.1-enzyme-stub