2 KINDS OF 2-HALO ACID DEHALOGENASES FROM PSEUDOMONAS SP YL INDUCED BY 2-CHLOROACRYLATE AND 2-CHLOROPROPIONATE

The bacterial isolates WS, WL, and YL, which were identified as Pseudo monas, grew in 2-chloro-acrylate (2-CAA) and 2-chloropropionate (2-CPA ) media to produce 2-halo acid dehalogenases. Pseudomonas sp. YL showe d the highest 2-CPA dehalogenase activity among the three strains, and inducibly produced two kinds of 2-halo acid dehalogenases in a medium containing either 2-CAA or 2-CPA. The 2-CAA-induced enzyme catalyzed dehalogenation of D- and L-2-CPA to produce L- and D-lactate, respecti vely. Its pH optimum of the dehalogenation and activity staining indic ated that a single enzyme catalyzes the dehalogenation of both enantio mers of 2-CPA. The 2-CPA-induced enzyme catalyzed production of D-lact ate from L-2-CPA, but did not act on D-2-CPA. The two dehalogenases ar e different from each other in mobility upon polyacrylamide gel electr ophoresis and sensitivity towards thiol reagents.