title: Inhibition of a viral enzyme by a small-molecule dimer disruptor.
abstract: We identified small-molecule dimer disruptors that inhibit an essential dimeric protease of human Kaposi's sarcoma-associated herpesvirus (KSHV) by screening an alpha-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 1H-13C HSQC titration using selectively labeled 13C-Met samples revealed that monomeric protease is enriched in the presence of inhibitor. 1H-15N 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.
authors.affiliation: Graduate Group in Biochemistry and Molecular Biology, University of California, San Francisco, California, USA.
authors.forename: Tina
authors.initials: T
authors.lastname: Shahian
authors.forename: Gregory M
authors.initials: GM
authors.lastname: Lee
authors.forename: Ana
authors.initials: A
authors.lastname: Lazic
authors.forename: Leggy A
authors.initials: LA
authors.lastname: Arnold
authors.forename: Priya
authors.initials: P
authors.lastname: Velusamy
authors.forename: Christina M
authors.initials: CM
authors.lastname: Roels
authors.forename: R Kiplin
authors.initials: RK
authors.lastname: Guy
authors.forename: Charles S
authors.initials: CS
authors.lastname: Craik
mesh_terms: D001665:Binding Sites; D019288:Herpesvirus 8, Human / Q000187:drug effects* / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D008958:Models, Molecular; D017354:Point Mutation; D011480:Protease Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D011487:Protein Conformation; D055503:Protein Multimerization / Q000187:drug effects*; D054852:Small Molecule Libraries / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D013379:Substrate Specificity
chemical_list: D011480:Protease Inhibitors; D054852:Small Molecule Libraries