Article ID Journal Published Year Pages File Type
2185037 Journal of Molecular Biology 2011 18 Pages PDF
Abstract

All members of the human herpesvirus protease (HHV Pr) family are active as weakly associating dimers but inactive as monomers. A small-molecule allosteric inhibitor of Kaposi's sarcoma-associated herpesvirus protease (KSHV Pr) traps the enzyme in an inactive monomeric state where the C-terminal helices are unfolded and the hydrophobic dimer interface is exposed. NMR titration studies demonstrate that the inhibitor binds to KSHV Pr monomers with low micromolar affinity. A 2.0-Å-resolution X-ray crystal structure of a C-terminal truncated KSHV Pr–inhibitor complex locates the binding pocket at the dimer interface and displays significant conformational perturbations at the active site, 15 Å from the allosteric site. NMR and CD data suggest that the small molecule inhibits human cytomegalovirus protease via a similar mechanism. As all HHV Prs are functionally and structurally homologous, the inhibitor represents a class of compounds that may be developed into broad-spectrum therapeutics that allosterically regulate enzymatic activity by disrupting protein–protein interactions.

Graphical AbstractFigure optionsDownload full-size imageDownload high-quality image (253 K)Download as PowerPoint slideResearch Highlights► First presentation of an allosterically inhibited HHV Pr monomer crystal structure. ► Inhibitor binds to monomeric protease in the absence of the interfacial helices. ► Trapping an inactivate KSHV Pr monomeric state subsequently inhibits dimerization. ► Loss of helices at the dimer interface disrupts enzyme active-site conformation. ► Small-molecule binding pocket is conserved among HHV Prs.

Related Topics
Life Sciences Biochemistry, Genetics and Molecular Biology Cell Biology
Authors
, , , , ,