Shooter K V
Chem Biol Interact. 1976 May;13(2):151-63. doi: 10.1016/0009-2797(76)90004-1.
The degradation in alkali of normal DNA and DNA alkylated with dimethyl sulphate (DMS), N-methyl-N-nitrosourea (MNUA) and N-ethyl-N-nitrosourea (ENUA) has been investigated using analytical ultracentrifugation techniques. For control T7-DNA (w.st. denatured form 12.5 - 10(6) daltons) the rate of degradation at 37 degrees varies from 0.14 breaks/molecule/h in 0.1 M NaOH to 1.2 breaks/molecule/h in 0.4 M NaOH. When DNA is alkylated with reagents known to produce phosphotriesters addition of alkali leads to an initial rapid degradation not observed with control DNA. Ethyl phosphotriesters are hydrolysed at about half the rate of methyl phosphotriesters. Approximately one third of the methyl or ethyl phosphotriesters present hydrolyse to give breaks in the DNA chain.
利用分析超速离心技术研究了正常DNA以及用硫酸二甲酯（DMS）、N-甲基-N-亚硝基脲（MNUA）和N-乙基-N-亚硝基脲（ENUA）烷基化的DNA在碱中的降解情况。对于对照T7-DNA（重量沉降变性形式为12.5 - 10⁶道尔顿），在37℃时，其在0.1 M NaOH中的降解速率为0.14次断裂/分子/小时，在0.4 M NaOH中为1.2次断裂/分子/小时。当DNA用已知能产生磷酸三酯的试剂烷基化后，加入碱会导致最初快速降解，而对照DNA未观察到这种情况。乙基磷酸三酯的水解速率约为甲基磷酸三酯的一半。大约三分之一的甲基或乙基磷酸三酯水解会导致DNA链断裂。
