Smol'janinova T I, Zhidkov V A, Sokolov G V
Nucleic Acids Res. 1982 Mar 25;10(6):2121-34. doi: 10.1093/nar/10.6.2121.
The titration curves of nitrogen bases and fractions of disordered nucleotide pairs are obtained during DNA protonation. It is shown that purine bases are the first sites of the DNA double helix protonation. The cytosine protonation is due to proton-induced conformational transition within GC pairs with the sequence proton transfer from (N-7) of guanine to (N-3) of cytosine. Within DNA with unwound regions the bases are protonated in the following order: cytosine, adenine, guanine. It is shown that GC pairs are the primary centres in which the unwinding of protonated DNAs occurs.
在DNA质子化过程中获得了氮碱基和无序核苷酸对片段的滴定曲线。结果表明,嘌呤碱基是DNA双螺旋质子化的首个位点。胞嘧啶的质子化是由于质子诱导的GC碱基对构象转变,质子从鸟嘌呤的(N-7)转移至胞嘧啶的(N-3)。在具有解旋区域的DNA中,碱基按以下顺序质子化:胞嘧啶、腺嘌呤、鸟嘌呤。结果表明,GC碱基对是质子化DNA发生解旋的主要中心。