1MRA:
reference: Mechanism of the reaction catalyzed by mandelate racemase: structure and mechanistic properties of the D270N mutant., Schafer SL, Barrett WC, Kallarakal AT, Mitra B, Kozarich JW, Gerlt JA, Clifton JG, Petsko GA, Kenyon GL, Biochemistry 1996 May 7;35(18):5662-9. PMID: 8639525

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