溴代胞嘧啶对三螺旋DNA稳定性的影响  

INFLUENCES OF SUBSTITUTION OF BROMIDE CYTOSINE ON STABILITY OF TRIPLEX DNA

作　　者：李清[1] 白春礼[1] ImshikLee 杨林静[1] 邓文礼[1] 王琛[1] 王乃新[1] 刘次全[2] 

机构地区：[1]中国科学院化学研究所 [2]中国科学院昆明动物研究所

出　　处：《计算机与应用化学》1999年第1期9-13,共5页Computers and Applied Chemistry

基　　金：中国科学院"九五"重大科研项目;国家自然科学基金

摘　　要：研究了三螺旋ＤＮＡ中胞嘧啶被５－溴胞嘧啶取代后的稳定性问题。通过建立ＣＧＣ，ＣＧＢｒＣ，ＢｒＣＧＣ和ＢｒＣＧＢｒＣ４种模型，并采用ＩｎｓｉｇｈｔⅡ软件包中的Ｄｉｓｃｏｖｅｒ程序进行计算模拟，发现用５－溴胞嘧啶取代三螺旋ＤＮＡ分子中的胞嘧啶后，整个分子的稳定性有所降低。同时，当用５－溴胞嘧啶取代三螺旋ＤＮＡ不同链上的胞嘧啶时，被取代链的碱基堆积能显著增高，导致分子链内稳定性降低，但被取代链和相邻链间相互作用能有所降低，使得链间作用趋向稳定。The influences of substitution of 5 bromide cytosine for cytosine in triplex DNA on whose stability are discussed in this paper. The program Discover in the software package of Insight Ⅱ was employed to simulate the substituted triplex DNA with the four models of CGC, CG Br C, Br CGC and Br CG Br C. The phenomenon of the substitution of 5 bromide cytosine for cytosine in triplex DNA indicates that. The stability of whole molecule is reduced. The phenomenon of the substitution in different chains of triplex DNA also shows that the base stacking energy of substituted chain increases obviously, which results in the decrease of internal stability of the molecule chain.However,the reduction of interaction energy between substituted chain and the neighbored chains leads to the interaction of chains remaining more stable.

关 键 词：三螺旋DNA DNA 稳定性 胞嘧啶 溴代胞嘧啶 

分 类 号：Q523.02[生物学—生物化学]