1oz6
From Proteopedia
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X-ray structure of acidic phospholipase A2 from Indian saw-scaled viper (Echis carinatus) with a potent platelet aggregation inhibitory activity
Overview
The crystal structure of an acidic phospholipase A(2) from the venom of, Echis carinatus (saw-scaled viper; scPLA(2)) has been determined at 2.6 A, resolution and refined to a crystallographic R factor of 0.192. Although, the overall structure of scPLA(2) is essentially similar to those of other, group II acidic PLA(2)s from different species, it shows unique features, in several parts. Particularly noteworthy is the C-terminal part, which, folds differently to those of other group II PLA(2)s. This part is, considered to be responsible for inhibition of the platelet-aggregation, activity. The calcium-binding loop is tightly organized with sevenfold, coordination. Another striking feature of scPLA(2) is the involvement of, Asn79 O(delta1) of a symmetry-related molecule in a coordination linkage, with Ca(2+) of the calcium-binding loop. This is the first observation of, an internal metal ion participating in an intermolecular interaction. The, beta-wing of a molecule is deeply inserted into the hydrophobic channel of, another molecule and forms several intermolecular interactions. This, results in the formation of an infinite chain of molecules. These chains, are stacked in an antiparallel arrangement in the crystals.
About this Structure
1OZ6 is a Single protein structure of sequence from Echis carinatus with CA as ligand. Active as Phospholipase A(2), with EC number 3.1.1.4 Full crystallographic information is available from OCA.
Reference
Structure of an acidic phospholipase A2 from Indian saw-scaled viper (Echis carinatus) at 2.6 A resolution reveals a novel intermolecular interaction., Jasti J, Paramasivam M, Srinivasan A, Singh TP, Acta Crystallogr D Biol Crystallogr. 2004 Jan;60(Pt 1):66-72. Epub 2003, Dec 18. PMID:14684894
Page seeded by OCA on Sun Nov 25 01:42:22 2007
