Off-campus University of Richmond users: To download campus access theses, please use the following link to log in to our proxy server with your university username and password.
Date of Award
Restricted Thesis: Campus only access
Bachelor of Science
Biochemistry & Molecular Biol.
Dr. Michelle Hamm
8-oxo-2'-deoxyguanosine (OdG) , a promutagenic lesion, arises from a reaction between 2'-deoxyguanosine (dG) and reactive oxygen species (ROS) such as peroxides, hydroxy radicals, and superoxides. ROS are produced from environmental carcinogens, radiation exposure, and metabolic respiration. OdG can base pair with both 2'-deoxycytidine (dC) and and 2' deoxyadenosine (dA), the latter of which causes dG to thymidine (dT) transversions. These mutations may be responsible for the link between OdG and aging, cancer, lupus, and
rheumatoid arthritis. To examine the preference for dCTP and dATP incorporation opposite OdG, the A-family polymerase Klen-Taq-1 (KT) was studied. KT is a Kienow-Fragment (KF) analog of Taq DNA polymerase from Thermophilus aquaticus and is more stable than KF while also lacking a 3'- exonuclease site. Previous studies have determined that potential steric clashing between a major groove amino acid and the C2- and C8- positions of OdG is critical in determining the efficiency of dCTP or dATP incorporation. KT (like KF) possesses a methionine in the major groove (Met672) rather than the isoleucine that is found in A-family polymerase I from the bacterium Bacillus Stearothermophilus (BF). The activity of dCTP and dATP incorporation opposite OdG and seven of its analogues was examined with wild-type KT and compared with wild-type BF to study major groove steric clashing with the C2- and C8- positions and their importance to OdG mutagenicity.
Byram, Nicole, "Importance of Met672 in the mutagenic potential of 8-oxo-2'-deoxyguanosine (OdG) with Klen-Taq polymerase" (2017). Honors Theses. 985.