Addition of racemase activity

As mentioned above, changing Cys 188 to a weak proton donor, Ser, and introducing Cys instead of Gly74 brought about the inversion of enantioselectivity of 

As expected, the Gly74Cys single mutant enzyme exhibited racemase activity to some arylpropionates as summarized in Table 4. In general, good substrates 

decarboxylase of disubstituted malonic acid could be easily converted to racemase of the corresponding monobasic acid, in spite of the fact that decarboxylation and racemization are quite different from each other. The key for the success is the mechanistic consideration focusing on the fact that the intermediate of both reactions is the same type of enolate of monobasic carboxylic acid. 

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