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1khq
From Proteopedia
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ORTHORHOMBIC FORM OF PAPAIN/ZLFG-DAM COVALENT COMPLEX
Overview
The three-dimensional structure of two polymorphs of a ZLFG-CH2-papain, covalent complex has been determined by X-ray crystallography. The, structures indicate that: (i) the methylene carbon atom of the inhibitor, is covalently bound to the Sgamma atom of Cys25 of papain; (ii) the, hydrophobic S2 pocket formed by Pro68, Val133, Val157, and Asp158 is, occupied by the inhibitor's phenylalanyl P2 side chain; (iii) extensive, hydrogen bonding and hydrophobic interactions are responsible for the, interaction of the inhibitor with the enzyme. Comparison with similar, structures suggests that in covalent complexes preservation of main, chain-main chain interactions between the enzyme and the inhibitor may, have higher priority than the P-S interactions.
About this Structure
1KHQ is a Single protein structure of sequence from Carica papaya. Active as Papain, with EC number 3.4.22.2 Full crystallographic information is available from OCA.
Reference
Two polymorphs of a covalent complex between papain and a diazomethylketone inhibitor., Janowski R, Kozak M, Jankowska E, Grzonka Z, Jaskolski M, J Pept Res. 2004 Oct;64(4):141-50. PMID:15357669
Page seeded by OCA on Tue Nov 20 19:14:50 2007
