1b4w: Difference between revisions

The basic phospholipase A2 (PLA2) from the venom of Agkistrodon halys, Pallas is a potent hemolytic toxin and anticoagulant. Crystal structure of, the enzyme complexed with detergent n-octyl beta-D-glucopyranoside, (beta-OG) in monoclinic crystal form has been determined to 2.6 A, resolution. Beta-OG molecules were found in the hydrophobic channels of, the enzyme. SDS-PAGE and dynamic light scattering measurements showed that, the enzyme had a strong tendency to dimerise in aqueous solution. In the, crystal structure the enzyme molecules associate into a tetramer with, pseudo 222 symmetry, and the interfacial recognition site linked dimers, constituting the tetramer have intensive interface interactions, and may, be stable in solution. The structure reveals a unique positively charged, face at the C-terminal region and a characteristic non-cationic, 'anticoagulant' region (53-77). The face is supposed to be the hemolytic, site, and based on sequence and structure comparison residues Trp70 and, Glu53 instead of the basic residues in 'anticoagulant' region might play, an important role in the anticoagulant activity.

1B4W is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Gloydius_halys Gloydius halys] with BOG as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Phospholipase_A(2) Phospholipase A(2)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.4 3.1.1.4] Structure known Active Sites: AC1, AC2, AC3 and AC4. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1B4W OCA].  

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