On March 7, 2003, Abu, Mika; Waters, Timothy R. published an article.COA of Formula: C6H5N3O The title of the article was The Main Role of Human Thymine-DNA Glycosylase Is Removal of Thymine Produced by Deamination of 5-Methylcytosine and Not Removal of Ethenocytosine. And the article contained the following:
Metabolites of vinyl chloride react with cytosine in DNA to form 3,N4-ethenocytosine. Recent studies suggest that ethenocytosine is repaired by the base excision repair pathway with the ethenobase being removed by thymine-DNA glycosylase. Here single turnover kinetics have been used to compare the excision of ethenocytosine by thymine-DNA glycosylase with the excision of thymine. The effect of flanking DNA sequence on the excision of ethenocytosine was also investigated. The 34-bp duplexes studied here fall into three categories. Ethenocytosine base-paired with guanine within a CpG site (i.e. CpG·εC-DNA) was by far the best substrate having a specificity constant (k2/Kd) of 25.1×106 M-1 s-1. The next best substrates were DNA duplexes containing TpG·εC, GpG·εC, and CpG·T. These had specificity constants 45-130 times smaller than CpG·εC-DNA. The worst substrates were DNA duplexes containing ApG·εC and TpG·T, which had specificity constants, resp., 1,600 and 7,400 times lower than CpG·εC-DNA. DNA containing ethenocytosine was bound much more tightly than DNA containing a G·T mismatch. This is probably because thymine-DNA glycosylase can flip out ethenocytosine from a G·εC base pair more easily than it can flip out thymine from a G·T mismatch. Because thymine-DNA glycosylase has a larger specificity constant for the removal of ethenocytosine, it has been suggested its primary purpose is to deal with ethenocytosine. However, these results showing that thymine-DNA glycosylase has a strong sequence preference for CpG sites in the excision of both thymine and ethenocytosine suggest that the main role of thymine-DNA glycosylase in vivo is the removal of thymine produced by deamination of 5-methylcytosine at CpG sites. The experimental process involved the reaction of Imidazo[1,2-c]pyrimidin-5(6H)-one(cas: 55662-66-3).COA of Formula: C6H5N3O
The Article related to thymine dna glycosylase deamination methylcytosine ethenocytosine, Toxicology: Carcinogens, Mutagens, and Teratogens and other aspects.COA of Formula: C6H5N3O
Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem