OBJECTIVE: To isolate and identify a novel strain with cis-epoxysuccinate hydrolase (CESH) activity and to optimize its enzyme production. METHODS: The isolated strain was identified by electron microscopy, Biolog gram negative (GN) test, G+C (guanine plus cytosine) content measurement and 16S rDNA sequence. The purified enzymatic biotransformed product was identified by IR, 1H-NMR, 13C-NMR, MS and optical rotation analysis. Then the fermentation conditions for CESH production were optimized. RESULTS: A novel CESH-producing strain was isolated for biotransforming cis-epoxysuccinate to D(-)-tartaric acid. It was assigned to genus Bordetella and named Bordetella sp. BK-52. The optimal conditions were found to be 30 degrees C, pH 7.0, fermentation time 36 h, carbon source of saccharose, inorganic nitrogen source of ammonium sulfate and enzyme inducer of disodium cis-epoxysuccinate. Under these conditions, the maximum CESH activity reached 764 U/g biomass. CONCLUSION: The isolated Bordetella sp. BK-52 provided a new alternative for biosynthesis of D(-)-tartaric acid from cis-epoxysuccinate.
OBJECTIVE: To isolate and identify a novel strain with cis-epoxysuccinate hydrolase (CESH) activity and to optimize its enzyme production. METHODS: The isolated strain was identified by electron microscopy, Biolog gram negative (GN) test, G+C (guanine plus cytosine) content measurement and 16S rDNA sequence. The purified enzymatic biotransformed product was identified by IR, 1H-NMR, 13C-NMR, MS and optical rotation analysis. Then the fermentation conditions for CESH production were optimized. RESULTS: A novel CESH-producing strain was isolated for biotransforming cis-epoxysuccinate to D(-)-tartaric acid. It was assigned to genus Bordetella and named Bordetella sp. BK-52. The optimal conditions were found to be 30 degrees C, pH 7.0, fermentation time 36 h, carbon source of saccharose, inorganic nitrogen source of ammonium sulfate and enzyme inducer of disodium cis-epoxysuccinate. Under these conditions, the maximum CESH activity reached 764 U/g biomass. CONCLUSION: The isolated Bordetella sp. BK-52 provided a new alternative for biosynthesis of D(-)-tartaric acid from cis-epoxysuccinate.