Preparation and Analysis of Oligonucleotides Containing Lesions Resulting from C5‘-Oxidation
作者:Tetsuya Kodama、Marc M. Greenberg
DOI:10.1021/jo051666k
日期:2005.11.1
Hydrogen atom abstraction from the C5‘-position of nucleotides in DNA results in direct strand scission. The newly formed 5‘-termini of the cleaved DNA consists of alkali-labile fragments of the oxidized nucleotide. One terminus contains a 5‘-aldehyde as part of an otherwise undamaged nucleotide (T-al). A second more structurally distinct product that is produced in lower yields results from cleavage of the
从DNA中核苷酸的C5'位置提取氢原子会导致直接链断裂。切割的DNA的新形成的5'末端由氧化核苷酸的碱不稳定片段组成。一个末端含有5'-醛,作为否则未损坏的核苷酸(T-al)的一部分。C4'-C5'碳-碳键的断裂导致第二个结构更独特的产品,其收率较低。1,4-二氧代-2-磷酰基丁烷(DOB)是烷基化剂丁-2-烯-1,4-丁二酸酯的前体。为了促进对这些病变的研究,合成了包含DOB或T-al的寡脱氧核苷酸的方法在他们的5'端被开发出来。确定了这些损伤对双链体DNA的UV融解温度的影响及其裂解能力。T-al裂解非常慢(t 1/2 = 100.7 h),而DOB在37°C(pH 7.2)下的半衰期少于11 h。另外,DOB与Tris非常有效地形成了稳定的加合物,从而保护了无碱基位点不被裂解。