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A pyrophosphatase activity associated with purified HIV-1 particles.
- Source :
-
Biochimie [Biochimie] 2012 Dec; Vol. 94 (12), pp. 2498-507. Date of Electronic Publication: 2012 Jul 03. - Publication Year :
- 2012
-
Abstract
- Treatment of HIV-1 with nucleoside reverse transcription inhibitors leads to the emergence of resistance mutations in the reverse transcriptase (RT) gene. Resistance to 3'-azido-3'-deoxythymidine (AZT) and to a lesser extent to 2'-3'-didehydro-2'-3'-dideoxythymidine is mediated by phosphorolytic excision of the chain terminator. Wild-type RT excises AZT by pyrophosphorolysis, while thymidine-associated resistance mutations in RT (TAMs) favour ATP as the donor substrate. However, in vitro, resistant RT still uses pyrophosphate more efficiently than ATP. We performed in vitro (-) strong-stop DNA synthesis experiments, with wild-type and AZT-resistant HIV-1 RTs, in the presence of physiologically relevant pyrophosphate and/or ATP concentrations and found that in the presence of pyrophosphate, ATP and AZTTP, TAMs do not enhance in vitro (-) strong-stop DNA synthesis. We hypothesized that utilisation of ATP in vivo is driven by intrinsic low pyrophosphate concentrations within the reverse transcription complex, which could be explained by the packaging of a cellular pyrophosphatase. We showed that over-expressed flagged-pyrophosphatase was associated with HIV-1 viral-like particles. In addition, we demonstrated that when HIV-1 particles were purified in order to avoid cellular microvesicle contamination, a pyrophosphatase activity was specifically associated to them. The presence of a pyrophosphatase activity in close proximity to the reverse transcription complex is most likely advantageous to the virus, even in the absence of any drug pressure.<br /> (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)
- Subjects :
- Adenosine Triphosphate metabolism
Anti-HIV Agents metabolism
Anti-HIV Agents pharmacology
DNA, Viral genetics
DNA, Viral metabolism
Dideoxynucleotides metabolism
Diphosphates metabolism
Drug Resistance, Viral drug effects
Drug Resistance, Viral genetics
HIV Reverse Transcriptase antagonists & inhibitors
HIV Reverse Transcriptase genetics
HIV-1 drug effects
HIV-1 genetics
Kinetics
Mutation
Pyrophosphatases genetics
Stavudine metabolism
Stavudine pharmacology
Substrate Specificity
Thymine Nucleotides metabolism
Virion drug effects
Virion genetics
Zidovudine analogs & derivatives
Zidovudine metabolism
Zidovudine pharmacology
HIV Reverse Transcriptase metabolism
HIV-1 enzymology
Pyrophosphatases metabolism
Virion enzymology
Subjects
Details
- Language :
- English
- ISSN :
- 1638-6183
- Volume :
- 94
- Issue :
- 12
- Database :
- MEDLINE
- Journal :
- Biochimie
- Publication Type :
- Academic Journal
- Accession number :
- 22766015
- Full Text :
- https://doi.org/10.1016/j.biochi.2012.06.025