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Molecular docking of cathepsin L inhibitors in the binding site of papain.

ABSTRACT: The papain/CLIK-148 coordinate system was employed as a model to study the interactions of a nonpeptide thiocarbazate inhibitor of cathepsin L ( 1). This small molecule inhibitor, a thiol ester containing a diacyl hydrazine functionality and one stereogenic center, was most active as the S-enantiomer, with an IC 50 of 56 nM; the R-enantiomer ( 2) displayed only weak activity (33 microM). Correspondingly, molecular docking studies with Extra Precision Glide revealed a correlation between score and biological activity for the two thiocarbazate enantiomers when a structural water was preserved. The molecular interactions between 1 and papain were very similar to the interactions observed for CLIK-148 ( 3a and 3b) with papain, especially with regard to the hydrogen-bonding and lipophilic interactions of the ligands with conserved residues in the catalytic binding site. Subsequent docking of virtual compounds in the binding site led to the identification of a more potent inhibitor ( 5), with an IC 50 of 7.0 nM. These docking studies revealed that favorable energy scores and correspondingly favorable biological activities could be realized when the virtual compound design included occupation of the S2, S3, and S1' subsites by hydrophobic and aromatic functionalities of the ligand, and at least three hydrogen bonding contacts between the ligand and the conserved binding site residues of the protein.

SUBMITTER: Beavers MP

PROVIDER: S-EPMC2923042 | biostudies-literature | 2008 Jul

REPOSITORIES: biostudies-literature

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Molecular docking of cathepsin L inhibitors in the binding site of papain.

Beavers Mary Pat MP Myers Michael C MC Shah Parag P PP Purvis Jeremy E JE Diamond Scott L SL Cooperman Barry S BS Huryn Donna M DM Smith Amos B AB

Journal of chemical information and modeling 20080704 7

The papain/CLIK-148 coordinate system was employed as a model to study the interactions of a nonpeptide thiocarbazate inhibitor of cathepsin L ( 1). This small molecule inhibitor, a thiol ester containing a diacyl hydrazine functionality and one stereogenic center, was most active as the S-enantiomer, with an IC 50 of 56 nM; the R-enantiomer ( 2) displayed only weak activity (33 microM). Correspondingly, molecular docking studies with Extra Precision Glide revealed a correlation between score an ...[more]

PMID: 18598021

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Dataset Information

Molecular docking of cathepsin L inhibitors in the binding site of papain.

Publications

Molecular docking of cathepsin L inhibitors in the binding site of papain.

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