ERA

Download the full-sized PDF of The mechanism of action of cidofovir and (S)-9-(3-hydroxy-2-phosphonomethoxypropyl)adenine against viral polymerasesDownload the full-sized PDF

Analytics

Share

Permanent link (DOI): https://doi.org/10.7939/R35K7X

Download

Export to: EndNote  |  Zotero  |  Mendeley

Communities

This file is in the following communities:

Graduate Studies and Research, Faculty of

Collections

This file is in the following collections:

Theses and Dissertations

The mechanism of action of cidofovir and (S)-9-(3-hydroxy-2-phosphonomethoxypropyl)adenine against viral polymerases Open Access

Descriptions

Other title
Subject/Keyword
(S)-HPMPA
Antiviral
DNA Polymerase
Vaccinia
Reverse Transcriptase
Nucleotide Analog
Cidofovir
Retrovirus
HIV-1
Poxvirus
Type of item
Thesis
Degree grantor
University of Alberta
Author or creator
Magee, Wendy C
Supervisor and department
Evans, David H (Medical Microbiology and Immunology)
Examining committee member and department
Tyrrell, D Lorne J (Medical Microbiology and Immunology)
Humar, A (Medicine)
Hobman, T (Cell Biology)
Götte, M (Microbiology and Immunology, McGill University)
Department
Department of Medical Microbiology and Immunology
Specialization

Date accepted
2009-08-21T17:50:22Z
Graduation date
2009-11
Degree
Doctor of Philosophy
Degree level
Doctoral
Abstract
The nucleoside phosphonates cidofovir (CDV) and (S)-9-[3-hydroxy-(2-phosphonomethoxy)propyl]adenine [(S)-HPMPA] are analogs of dCMP and dAMP, respectively. Collectively these drugs are effective inhibitors of a wide range of DNA viruses, RNA viruses, and retroviruses. Because they are nucleotide analogs, the drugs are thought to target viral polymerases and inhibit viral genome replication. However, the precise mechanism by which these drugs block viral growth remains unclear. We have studied the mechanism of action of these antivirals against three viral polymerases, vaccinia virus DNA polymerase and the reverse transcriptases from human immunodeficiency virus type 1 (HIV-1) and Moloney murine leukemia virus (MMLV). In vitro experiments using the active intracellular metabolites of CDV and (S)-HPMPA, CDV diphosphate (CDVpp) and (S)-HPMPA diphosphate [(S)-HPMPApp], respectively, showed that the drugs are substrates for each enzyme and can be incorporated into DNA without causing chain termination, although the rate of DNA elongation catalyzed by the vaccinia virus and MMLV polymerases is slowed. We have also found that incorporation of CDV or (S)-HPMPA blocked the 3′-to-5′ proofreading exonuclease activity of the vaccinia virus DNA polymerase. In addition, we determined that when these drugs are incorporated into a template DNA strand, they inhibited replication across the drug lesion. These results indicate that although CDV and (S)-HPMPA can inhibit some enzymes when incorporated into the primer strand, the main effects of drug action occur when they are incorporated into the template strand. Our findings point to a new avenue of targeted drug design, one in which nucleoside or nucleotide analogues are efficient substrates for the viral nucleic acid polymerase, do not inhibit primer strand elongation, but exert their effects in subsequent rounds of nucleic acid synthesis.
Language
English
DOI
doi:10.7939/R35K7X
Rights
Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.
Citation for previous publication

File Details

Date Uploaded
Date Modified
2014-05-02T17:45:23.898+00:00
Audit Status
Audits have not yet been run on this file.
Characterization
File format: pdf (Portable Document Format)
Mime type: application/pdf
File size: 7054874
Last modified: 2015:10:12 20:35:50-06:00
Filename: Magee_Wendy_Fall 2009.pdf
Original checksum: d520bbfe4b64d9f683427b57e3b468fc
Well formed: false
Valid: false
Status message: Invalid object number or object stream offset=7024326
Activity of users you follow
User Activity Date