Acetolactate Synthase (ALS) (乙酰乳酸合酶)

Acetohydroxyacid synthase (ALS), a thiamine diphosphate-dependent enzyme, can condense either two pyruvate molecules to form acetolactate for synthesizing Lvaline and L-leucine or pyruvate with 2-ketobutyrate to form acetohydroxybutyrate for synthesizing L-isoleucine. Because the key reaction catalyzed by acetohydroxyacid synthase in the biosynthetic pathways of branched-chain amino acids (valine, leucine, and isoleucine) exists in plants, fungi, archaea, and bacteria, but not in animals, acetohydroxyacid synthase becomes a potential target for developing novel herbicides and antimicrobial compounds.