Deoxyguanosine
Deoxyguanosine (dG) is composed of the purine nucleobase guanine linked by its N9 nitrogen to the C1 carbon of deoxyribose. It is similar to guanosine, but with one hydroxyl group removed from the 2' position of the ribose sugar (making it deoxyribose). If a phosphate group is attached at the 5' position, it becomes deoxyguanosine monophosphate.
Deoxyguanosine is one of the four deoxyribonucleosides that make up DNA.[1]
Potential Damage to Deoxyguanosine
[edit]Deoxyguanosine is a base that is vulnerable to reactive oxygen species (ROS) because of its comparatively lower oxidation potential. As a result, ROS can oxidize dG to make 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG). This modification is known as a pre-mutagenic lesion, meaning that the damage can still be repaired, but can lead to a mutation if left alone. The oxidation of dG can be detrimental to the genome since 8-oxodG base pairs with deoxyadenosine (dA) instead of the deoxycytidine (dC), which is the proper Watson-Crick base pair. Consequently, if the lesion is not repaired via the mismatch repair mechanism, during DNA replication a dA will take the place of the dC, resulting in a mutation.[2]
Deoxyguanosine is also a base that is prone to reacting with carcinogens, such as polyaromatic hydrocarbons (PAHs). Once the PAHs are metabolized and made stable in the intracellular environment, they can react with dG to form 7-methyldeoxyguanosine or O6-methyldeoxyguanosine. The presence of these modifications can then lead to downstream effects that lower the fidelity of DNA replication and potentially cause mutations.[3]
See also
[edit]References
[edit]- ↑ "Human Metabolome Database (HMDB) metabocard for Deoxyguanosine (HMDB0000085)".
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- ↑ Peterson, L.A.; Urban, A.M.; Hecht, S.S. (2010-01-01). "Carcinogenic Effects of Cigarette Smoke on the Respiratory Tract". Comprehensive Toxicology (Second Edition): 351–377. doi:10.1016/B978-0-08-046884-6.00919-2.