1J9W:
reference: Crystal structure of a zinc-activated variant of human carbonic anhydrase I, CA I Michigan 1: evidence for a second zinc binding site involving arginine coordination., Ferraroni M, Tilli S, Briganti F, Chegwidden WR, Supuran CT, Wiebauer KE, Tashian RE, Scozzafava A, Biochemistry. 2002 May 21;41(20):6237-44. PMID: 12009884

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