5ZMY:
reference: Structural insight into the catalytic mechanism of a cis-epoxysuccinate hydrolase producing enantiomerically pure d(-)-tartaric acid., Dong S, Liu X, Cui GZ, Cui Q, Wang X, Feng Y, Chem Commun (Camb). 2018 Jul 26;54(61):8482-8485. doi: 10.1039/c8cc04398a. PMID: 30003205

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