1KHQ

ORTHORHOMBIC FORM OF PAPAIN/ZLFG-DAM COVALENT COMPLEX

Summary for 1KHQ

• Entry DOI: 10.2210/pdb1khq/pdb
• Related: 1CVZ 1KHP 1PAD 1PE6 1PIP 1POP 1PPD 1PPN 1PPP 1STF 2PAD 5PAD 6PAD 9PAP
• Related PRD ID: PRD_000309
• Descriptor: Papain, peptidic inhibitor (3 entities in total)
• Functional Keywords: protease inhibitor, diazomethylketone inhibitor, irreversible inhibitor, hydrolase-hydrolase inhibitor complex, hydrolase/hydrolase inhibitor
• Biological source: Carica papaya (papaya)
• Total number of polymer chains: 2
• Total formula weight: 23964.30

Authors

Janowski, R.,Kozak, M.,Jankowska, E.,Grzonka, Z.,Jaskolski, M. (deposition date: 2001-11-30, release date: 2003-09-09, Last modification date: 2024-11-06)

Primary citation

Janowski, R.,Kozak, M.,Jankowska, E.,Grzonka, Z.,Jaskolski, M.
Two polymorphs of a covalent complex between papain and a diazomethylketone inhibitor
J.Pept.Res., 64:141-150, 2004

PubMed Abstract: 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.

PubMed: 15357669
DOI: 10.1111/j.1399-3011.2004.00181.x

Experimental method

X-RAY DIFFRACTION (1.6 Å)