Crystal structures of HIV protease V82A and L90M mutants reveal changes in the indinavir-binding site.
The crystal structures of the wild-type HIV-1 protease (PR) and the two resistant variants, PR(V82A) and PR(L90M), have been determined in complex with the antiviral drug, indinavir, to gain insight into the molecular basis of drug resistance. V82A and L90M correspond to an active site mutation and nonactive site mutation, respectively. The inhibition (K(i)) of PR(V82A) and PR(L90M) was 3.3- and 0.16-fold, respectively, relative to the value for PR. They showed only a modest decrease, of 10-15%, in their k(cat)/K(m) values relative to PR. The crystal structures were refined to resolutions of 1.25-1.4 A to reveal critical features associated with inhibitor resistance. PR(V82A) showed local changes in residues 81-82 at the site of the mutation, while PR(L90M) showed local changes near Met90 and an additional interaction with indinavir. These structural differences concur with the kinetic data.
Mahalingam
Bhuvaneshwari
B
Department of Biology, Georgia State University, PO Box 4010, Atlanta, GA 30302-4010, USA.
Wang
Yuan-Fang
YF
Boross
Peter I
PI
Tozser
Jozsef
J
Louis
John M
JM
Harrison
Robert W
RW
Weber
Irene T
IT
D019943:Amino Acid Substitution; D000596:Amino Acids / Q000737:chemistry; D001665:Binding Sites; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D016333:HIV Protease / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D017320:HIV Protease Inhibitors / Q000378:metabolism* / Q000494:pharmacology; D006860:Hydrogen Bonding; D019469:Indinavir / Q000378:metabolism* / Q000494:pharmacology; D007700:Kinetics; D008958:Models, Molecular; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013816:Thermodynamics; D014508:Urea / Q000737:chemistry
D000596:Amino Acids; D017320:HIV Protease Inhibitors; D009842:Oligopeptides; D011994:Recombinant Proteins; D019469:Indinavir; D014508:Urea; D016333:HIV Protease