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A novel acetate-bound complex of human carbonic anhydrase II.

ABSTRACT: The enzyme human carbonic anhydrase II (hCAII) crystallized in an acetate-bound complex belonging to space group P2(1)2(1)2(1), with unit-cell parameters a = 42.3, b = 71.8, c = 74.0 A. The structure was solved by the molecular-replacement method and refined to an R value of 0.18 and an R(free) of 0.21. The acetate molecule replaced the zinc-bound water molecule in the structure, differing from previous reports regarding the site of acetate binding. This mode of binding disrupts the hydrogen-bonded solvent network required for activity of the enzyme. This mode of inhibitor binding is a novel one that has not been observed previously.

SUBMITTER: Mazumdar PA

PROVIDER: S-EPMC2374158 | biostudies-literature | 2008 Mar

REPOSITORIES: biostudies-literature

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A novel acetate-bound complex of human carbonic anhydrase II.

Mazumdar Pooja Anjali PA Kumaran Desigan D Swaminathan Subramanyam S Das Amit Kumar AK

Acta crystallographica. Section F, Structural biology and crystallization communications 20080223 Pt 3

The enzyme human carbonic anhydrase II (hCAII) crystallized in an acetate-bound complex belonging to space group P2(1)2(1)2(1), with unit-cell parameters a = 42.3, b = 71.8, c = 74.0 A. The structure was solved by the molecular-replacement method and refined to an R value of 0.18 and an R(free) of 0.21. The acetate molecule replaced the zinc-bound water molecule in the structure, differing from previous reports regarding the site of acetate binding. This mode of binding disrupts the hydrogen-bon ...[more]

PMID: 18323598

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