5Y2R:
reference: Active-site solvent replenishment observed during human carbonic anhydrase II catalysis., Kim JK, Lomelino CL, Avvaru BS, Mahon BP, McKenna R, Park S, Kim CU, IUCrJ. 2018 Jan 1;5(Pt 1):93-102. doi: 10.1107/S2052252517017626. eCollection, 2018 Jan 1. PMID: 29354275

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