Methods for producing optically active amino acids

A method for producing from one of the optical isomers (optical isomer I) of an amino acid represented by Formula (1):

• R—CH(NH2)—COOH (1)
• (wherein R is an optionally substituted C1-C12 alkyl group, an optionally substituted C4-C8 cycloalkyl group or an optionally substituted C6-C14 aryl group) the other of the optical isomers (optical isomer II), said method comprising reacting a biological material which has an ability of converting said one of the optical isomers (optical isomer I) to said the other of the optical isomers (optical isomer II), the isomerism being on the basis of an assymetric carbon atom to which both of an amino group and a carboxyl group are bound and said ability being not inhibited seriously by an amino acid transferase inhibitor β-chloro-D-alanine, β-chloro-L-alanine or gabaculine, with said one of the optical isomers (optical isomer I).