Spectroscopic analysis and synthesis of nucleoside analogs for lethal mutagenesis

Thesis: S.B. in Chemistry and Biology, Massachusetts Institute of Technology, Department of Chemistry, 2014.

Bibliographic Details
Main Author: Silvestre, Katherine J
Other Authors: John M. Essigmann.
Format: Thesis
Language:eng
Published: Massachusetts Institute of Technology 2015
Subjects:
Online Access:http://hdl.handle.net/1721.1/100159
_version_ 1811086137841680384
author Silvestre, Katherine J
author2 John M. Essigmann.
author_facet John M. Essigmann.
Silvestre, Katherine J
author_sort Silvestre, Katherine J
collection MIT
description Thesis: S.B. in Chemistry and Biology, Massachusetts Institute of Technology, Department of Chemistry, 2014.
first_indexed 2024-09-23T13:21:27Z
format Thesis
id mit-1721.1/100159
institution Massachusetts Institute of Technology
language eng
last_indexed 2024-09-23T13:21:27Z
publishDate 2015
publisher Massachusetts Institute of Technology
record_format dspace
spelling mit-1721.1/1001592019-04-12T12:08:43Z Spectroscopic analysis and synthesis of nucleoside analogs for lethal mutagenesis Silvestre, Katherine J John M. Essigmann. Massachusetts Institute of Technology. Department of Chemistry. Massachusetts Institute of Technology. Department of Chemistry. Chemistry. Thesis: S.B. in Chemistry and Biology, Massachusetts Institute of Technology, Department of Chemistry, 2014. Cataloged from PDF version of thesis. Includes bibliographical references (pages 34-35). The high mutation rate of HIV makes treatment of HIV/AIDS difficult, as the virus can develop resistance to existing therapeutics. A novel antiviral nucleoside analog, 5-Aza-5,6-dihydro-2'- deoxycytidine (KP1212), employs the mechanism of lethal mutagenesis to avoid the problem of drug resistance and use the virus's high mutation rate against it. KP1212 is incorporated into DNA by HIV reverse transcriptase (RT) but mispairs with adenine instead of guanine, increasing the rate of purine transitions. This increased mutation rate can push HIV over its error catastrophe limit, resulting in viral ablation. To understand how KP1212 induces lethal mutagenesis, VT NMR studies were conducted on KP1212. These experiments revealed that the enol tautomers of KP1212 are more prevalent than the keto tautomers, in contrast to native 2'-deoxycytidine (dC) which is predominately found in the keto-amino tautomer. The enol tautomers are able to base-pair with adenine, causing the increase rate of purine transitions observed in tissue culture and in clinical trials of KP1212. The distribution of KP1212 tautomers measured by VT NMR support tautomerization as the molecular mechanism for KP1212-induced lethal mutagenesis. VT NMR experiments on a variety of known mutagenic nucleoside analogs found that many of them, including 5-aza-2'-deoxycytidine (decitabine), did not show multiple tautomers and thus had other molecular mechanisms behind their mutagenicity. This suggested that breaking the aromaticity of the nucleobase in KP1212 had a significant effect on the distribution of tautomers. To understand this structural change, the hydrogenated nucleoside analog 5,6-dihydro-2'- deoxycytidine (DHdC) was synthesized via continuous-flow hydrogenation of dC. VT NMR studies show multiple tautomers for DHdC, demonstrating that hydrogenated nucleoside analogs could provide a variety of untested lethal mutagens for further study. by Katherine J. Silvestre. S.B. in Chemistry and Biology 2015-12-07T19:52:04Z 2015-12-07T19:52:04Z 2014 2014 Thesis http://hdl.handle.net/1721.1/100159 892339668 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 49 pages application/pdf Massachusetts Institute of Technology
spellingShingle Chemistry.
Silvestre, Katherine J
Spectroscopic analysis and synthesis of nucleoside analogs for lethal mutagenesis
title Spectroscopic analysis and synthesis of nucleoside analogs for lethal mutagenesis
title_full Spectroscopic analysis and synthesis of nucleoside analogs for lethal mutagenesis
title_fullStr Spectroscopic analysis and synthesis of nucleoside analogs for lethal mutagenesis
title_full_unstemmed Spectroscopic analysis and synthesis of nucleoside analogs for lethal mutagenesis
title_short Spectroscopic analysis and synthesis of nucleoside analogs for lethal mutagenesis
title_sort spectroscopic analysis and synthesis of nucleoside analogs for lethal mutagenesis
topic Chemistry.
url http://hdl.handle.net/1721.1/100159
work_keys_str_mv AT silvestrekatherinej spectroscopicanalysisandsynthesisofnucleosideanalogsforlethalmutagenesis