Inhibition of a viral enzyme by a small-molecule dimer disruptor

• Published in: Nature chemical biology Vol. 5; no. 9; pp. 640 - 646
• Main Authors: Roels, Christina M, Guy, R Kiplin, Shahian, Tina, Lazic, Ana, Craik, Charles S, Velusamy, Priya, Arnold, Leggy A, Lee, Gregory M
• Format: Journal Article
• Language: English
• Published: New York Nature Publishing Group US 01.09.2009; Nature Publishing Group
• Subjects: Binding Sites; Biochemical Engineering; Biochemistry; Bioorganic Chemistry; Cell Biology; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Chromatography; Enzymes; Herpes viruses; Herpesvirus 8, Human - drug effects; Herpesvirus 8, Human - enzymology; Herpesvirus 8, Human - genetics; Human herpesvirus 8; Humans; Inhibitors; Kaposi's sarcoma-associated herpesvirus; Models, Molecular; Molecular biology; Point Mutation; Protease inhibitors; Protease Inhibitors - chemical synthesis; Protease Inhibitors - chemistry; Protease Inhibitors - pharmacology; Protein Conformation; Protein Multimerization - drug effects; Sarcoma; Small Molecule Libraries - chemical synthesis; Small Molecule Libraries - chemistry; Small Molecule Libraries - pharmacology; Solubility; Substrate Specificity
• ISSN: 1552-4450; 1552-4469
• DOI: 10.1038/nchembio.192

We identified small-molecule dimer disruptors that inhibit an essential dimeric protease of human Kaposi's sarcoma–associated herpesvirus (KSHV) by screening an α-helical mimetic library. Next, we synthesized a second generation of low-micromolar inhibitors with improved potency and solubility. Complementary methods including size exclusion chromatography and 1 H- 13 C HSQC titration using selectively labeled 13 C-Met samples revealed that monomeric protease is enriched in the presence of inhibitor. 1 H- 15 N HSQC titration studies mapped the inhibitor binding site to the dimer interface, and mutagenesis studies targeting this region were consistent with a mechanism where inhibitor binding prevents dimerization through the conformational selection of a dynamic intermediate. These results validate the interface of herpesvirus proteases and other similar oligomeric interactions as suitable targets for the development of small-molecule inhibitors.