title: Biosensor-based kinetic characterization of the interaction between HIV-1 reverse transcriptase and non-nucleoside inhibitors.
abstract: Details of the interaction between HIV-1 reverse transcriptase and non-nucleoside inhibitors (NNRTIs) have been elucidated using a biosensor-based approach. This initial study was performed with HIV-1 reverse transcriptase mutant K103N, the phenethylthioazolylthiourea compound (PETT) MIV-150, and the three NNRTIs licensed for clinical use: nevirapine, delavirdine, and efavirenz. Mathematical evaluation of the experimental data with several interaction models revealed that the four inhibitors interacted with HIV-1 RT with varying degrees of complexity. The simplest adequate model accounted for two different conformations of the free enzyme, of which only one can bind the inhibitor, consistent with a previously hypothesized population-shift model including a preformation of the NNRTI binding site. In addition, a heterogeneous binding was observed for delavirdine, efavirenz, and MIV-150, indicating that two noncompetitive and kinetically distinct enzyme-inhibitor complexes could be formed. Furthermore, for these compounds, there were indications for ligand-induced conformational changes.
authors.affiliation: Department of Biochemistry and Organic Chemistry, Box 576, Uppsala University, SE-751 23 Uppsala, Sweden.
authors.forename: Matthis
authors.initials: M
authors.lastname: Geitmann
authors.forename: Torsten
authors.initials: T
authors.lastname: Unge
authors.forename: U Helena
authors.initials: UH
authors.lastname: Danielson
mesh_terms: D000480:Alkynes; D048588:Benzoxazines; D001665:Binding Sites; D015374:Biosensing Techniques / Q000379:methods*; D003521:Cyclopropanes; D020008:Delavirdine / Q000737:chemistry / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors* / Q000737:chemistry; D007700:Kinetics; D015394:Molecular Structure; D019829:Nevirapine / Q000737:chemistry / Q000494:pharmacology; D010078:Oxazines / Q000737:chemistry / Q000494:pharmacology; D011487:Protein Conformation; D011725:Pyridines / Q000737:chemistry / Q000494:pharmacology; D018894:Reverse Transcriptase Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D013997:Time Factors; D014508:Urea / Q000031:analogs & derivatives / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000480:Alkynes; D048588:Benzoxazines; D003521:Cyclopropanes; C510296:MIV 150; D010078:Oxazines; D011725:Pyridines; D018894:Reverse Transcriptase Inhibitors; D014508:Urea; D019829:Nevirapine; D020008:Delavirdine; D054303:HIV Reverse Transcriptase; C098320:efavirenz