Characterization of the reverse transcriptase of a human immunodeficiency virus type 1 group O isolate.
The catalytic properties and sensitivity to different inhibitors have been determined for the reverse transcriptase (RT) of group O human immunodeficiency virus type 1 (HIV-1). The RT-coding region was cloned from a new HIV-1 group O isolate from Spain, expressed in Escherichia coli, and purified by affinity chromatography. This new RT showed 79% amino acid sequence identity with the corresponding enzyme of group M subtype B strain BH10. The two enzymes showed very similar kinetics of RNA-dependent DNA polymerization using homopolymeric template-primers and RNase H specific activity. Inhibitor sensitivity to ddTTP and 3'-azido-2',3'-dideoxythymidine triphosphate (AZTTP) was also similar for both enzymes. However, the two enzymes differed dramatically in their sensitivity to several inhibitors. While the RT of the BH10 isolate was sensitive to nevirapine and loviride (IC50 ranged from 0.16 to 8.2 microM, depending on the substrates used), the enzyme of the Spanish HIV-1 group O isolate showed high-level resistance to those compounds (IC50 > 200 microM). The amino acid sequence of the RT of group O HIV-1 contains three amino acids (Cys-181, Glu-179, and Gly-98), which are found in group M subtype B strains resistant to nonnucleoside RT inhibitors. The recombinant group O HIV-1 RT should be useful for studies aimed at discovering and designing drugs directed toward group O isolates of HIV-1.
Quiñones-Mateu
M E
ME
Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Universidad Autónoma de Madrid, Spain.
Soriano
V
V
Domingo
E
E
Menéndez-Arias
L
L
D000328:Adult; D000595:Amino Acid Sequence; D019380:Anti-HIV Agents / Q000494:pharmacology; D001483:Base Sequence; D002384:Catalysis; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D015658:HIV Infections / Q000821:virology; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D015497:HIV-1 / Q000145:classification* / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D007700:Kinetics; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D013030:Spain
D019380:Anti-HIV Agents; D017931:DNA Primers; D004279:DNA, Viral; D018894:Reverse Transcriptase Inhibitors; D054303:HIV Reverse Transcriptase