Non-nucleoside analogue inhibitors bind to an allosteric site on HCV NS5B polymerase. Crystal structures and mechanism of inhibition.
X-ray crystal structures of two non-nucleoside analogue inhibitors bound to hepatitis C virus NS5B RNA-dependent RNA polymerase have been determined to 2.0 and 2.9 A resolution. These noncompetitive inhibitors bind to the same site on the protein, approximately 35 A from the active site. The common features of binding include a large hydrophobic region and two hydrogen bonds between both oxygen atoms of a carboxylate group on the inhibitor and two main chain amide nitrogen atoms of Ser(476) and Tyr(477) on NS5B. The inhibitor-binding site lies at the base of the thumb domain, near its interface with the C-terminal extension of NS5B. The location of this inhibitor-binding site suggests that the binding of these inhibitors interferes with a conformational change essential for the activity of the polymerase.
Wang
Meitian
M
Canadian Institutes for Health Research Group in Protein Structure and Function, Department of Biochemistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada.
Ng
Kenneth K-S
KK
Cherney
Maia M
MM
Chan
Laval
L
Yannopoulos
Constantin G
CG
Bedard
Jean
J
Morin
Nicolas
N
Nguyen-Ba
Nghe
N
Alaoui-Ismaili
Moulay H
MH
Bethell
Richard C
RC
James
Michael N G
MN
D000495:Allosteric Site; D000595:Amino Acid Sequence; D001665:Binding Sites; D001667:Binding, Competitive; D018360:Crystallography, X-Ray; D004305:Dose-Response Relationship, Drug; D006860:Hydrogen Bonding; D020128:Inhibitory Concentration 50; D008956:Models, Chemical; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009584:Nitrogen; D009705:Nucleosides / Q000737:chemistry*; D010100:Oxygen; D011485:Protein Binding; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry; D012694:Serine / Q000737:chemistry; D014443:Tyrosine / Q000737:chemistry; D017361:Viral Nonstructural Proteins / Q000235:genetics*; D012324:RNA-Dependent RNA Polymerase
D009584:Nitrogen; D009705:Nucleosides; D010100:Oxygen; D011994:Recombinant Proteins; D012694:Serine; D014443:Tyrosine; D017361:Viral Nonstructural Proteins; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase