| Biotechnological preparations of L(+)-Tartaric acid have superceded chemical synthesize due to ecological and economical advantages. Bacterial cells with cis-epoxysuccinate hydrolase(ESH) activity are able to catalyse single step and stereospecific biohydrolysis of cis-epoxysuccinate yielding enantiomerically pure L(+)-Tartrate.In this paper,we investigate the biocatalytic properties of cis-epoxysuccinate hydrolase. The material of the experiment are bacteria cells(Corynebacterium sp. JZ-1) immobilized with cis-epoxysuccinate hydrolase activity.Immobilized bacteria cells converted sodium cis-epoxysuccinate (PH8.0) to L(+)-tartaric acid at 37°C with constant stiring(100r/min),the results show that Km of cis-epoxysuccinate hydrolase is 0.255mol/L,the maximal rate Vmax is 3.527μmol/min.When the PH of cis-epoxysuccinate sodium solution is in 8.0~9.0, the activity of cis-epoxysuccinate hydrolase is very high. Molybdate ions, tungstateions ions and maleic acid have great influence on the activity of cis-epoxysuccinate hydrolase,they are inhibitors of cis-epoxysuccinate hydrolase,so it is better to remove them off before the bioconversion. |
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