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1s1d
From Proteopedia
Structure and protein design of human apyrase
Overview
Hematophagous arthropods secrete a salivary apyrase that inhibits platelet activation by catabolizing ADP released from damaged tissues and blood cells. We report the X-ray crystal structures of a human enzyme of the soluble apyrase family in its apo state and bound to a substrate analog. The structures reveal a nucleotide binding domain comprising a five-blade beta propeller, binding determinants of the substrate and the active site, and an unusual calcium binding site with a potential regulatory function. Using a comparative structural biology approach, we were able to redesign the human apyrase so as to enhance its ADPase activity by more than 100-fold. The engineered enzyme is a potent inhibitor of platelet aggregation and may serve as the basis for the development of a new class of antithrombotic agents.
About this Structure
1S1D is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structure and protein design of a human platelet function inhibitor., Dai J, Liu J, Deng Y, Smith TM, Lu M, Cell. 2004 Mar 5;116(5):649-59. PMID:15006348 Page seeded by OCA on Sat May 3 08:10:23 2008
