HIV-1 protease molecular dynamics of a wild-type and of the V82F/I84V mutant: possible contributions to drug resistance and a potential new target site for drugs.
The protease from type 1 human immunodeficiency virus (HIV-1) is a critical drug target against which many therapeutically useful inhibitors have been developed; however, the set of viral strains in the population has been shifting to become more drug-resistant. Because indirect effects are contributing to drug resistance, an examination of the dynamic structures of a wild-type and a mutant could be insightful. Consequently, this study examined structural properties sampled during 22 nsec, all atom molecular dynamics (MD) simulations (in explicit water) of both a wild-type and the drug-resistant V82F/I84V mutant of HIV-1 protease. The V82F/I84V mutation significantly decreases the binding affinity of all HIV-1 protease inhibitors currently used clinically. Simulations have shown that the curling of the tips of the active site flaps immediately results in flap opening. In the 22-nsec MD simulations presented here, more frequent and more rapid curling of the mutant's active site flap tips was observed. The mutant protease's flaps also opened farther than the wild-type's flaps did and displayed more flexibility. This suggests that the effect of the mutations on the equilibrium between the semiopen and closed conformations could be one aspect of the mechanism of drug resistance for this mutant. In addition, correlated fluctuations in the active site and periphery were noted that point to a possible binding site for allosteric inhibitors.
Perryman
Alexander L
AL
University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0365, USA. aperryma@mccammon.ucsd.edu
Lin
Jung-Hsin
JH
McCammon
J Andrew
JA
D019943:Amino Acid Substitution; D001665:Binding Sites; D015195:Drug Design; D024882:Drug Resistance, Viral; D016333:HIV Protease / Q000737:chemistry* / Q000187:drug effects / Q000235:genetics; D017320:HIV Protease Inhibitors / Q000737:chemistry / Q000494:pharmacology; D015497:HIV-1 / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D019906:Nuclear Magnetic Resonance, Biomolecular; D017434:Protein Structure, Tertiary / Q000235:genetics
D017320:HIV Protease Inhibitors; D016333:HIV Protease