1MDL:
reference: Mechanism of the reaction catalyzed by mandelate racemase: structure and mechanistic properties of the K166R mutant., Kallarakal AT, Mitra B, Kozarich JW, Gerlt JA, Clifton JG, Petsko GA, Kenyon GL, Biochemistry 1995 Mar 7;34(9):2788-97. PMID: 7893690

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