4-hydroxy-2-oxovalerate aldolase

In enzymology, a 4-hydroxy-2-oxovalerate aldolase (EC4.1.3.39) is an enzyme that catalyzes the chemical reaction

Hence, this enzyme has one substrate, 4-hydroxy-2-oxopentanoate, and two products, acetaldehyde and pyruvate. Baker et al.. showed that BphI, a member of this family from Burkholderia xenovorans LB400 was able to utilize 4-hydroxy- 2-oxohexanoate (HOHA) with equal catalytic efficiency as 4-hydroxy-2-oxopentanoate, producing propionaldehyde + pyruvate. Furthermore, the enzyme was also able to catalyze the cleavage of 4-hydroxy-2-oxoheptanoate (HOHEP), forming butryaldehyde + pyruvate. Baker et al.. we also able to show that acetaldehyde and propionaldehyde are not released into the bulk solvent, but are channeled to an associated acetaldehyde dehydrogenase known as BphJ. This is the first demonstration of substrate channeling in this family of enzymes.