检测脱氨基速率的超灵敏方法及应用  

A Sensitive Assay for the Detection of Cytosine Deamination Rate and Its Application

作　　者：陈洪[1] 李雨民[2] 

机构地区：[1]DepartmentofChemistryDukeUniversity [2]中国医学科学院中国协和医科大学放射医学研究所,天津300192

出　　处：《生物化学与生物物理进展》1997年第5期405-409,共5页Progress In Biochemistry and Biophysics

摘　　要：脱氨基被认为是引起细胞突变的主要因素 ,如果这些脱氨基的产物不被修复 ,将引起转换(transition)突变 .为了理解DNA结构和其化学活性的关系 ,介绍一种新的灵敏的遗传学方法 ,它应用在DNA特定点的脱氨基速率的测定 .这种方法基于M 1 3mp2噬菌体内的 1acZα基因中的CCC脯氨酸密码子的反转突变 ,即每个脱氨基事件表现为在白色菌斑背景中的一个蓝色菌斑 ,其灵敏度可达1 0 5M1 3mp2DNA分子中检验出一个脱氨基事件 .此外 ,该法可以计算脱氨基动力学速率常数和反应活化能 .Deamination of bases is regarded as the major factor for mutation in DNA and it will induce transition mutation if the products of deamination have not heen repaired. Now a new sensitive genetic assay to determine quanti- tatively deamination of bases in DNA special site has been introduced to understand the relationship between DNA structure and its chemical activities. The assay is based on reversion of a mutant of CCC proline coding sequence which is located in Lac Z α gene of bacteriophage M13mp2 from a colorless to blue plaque phenotype. This approach is highly sensitive; deamination of a single cytosine residue in 105 M13mp2 DNA molecules can be detected. Besides, the kinetic rate constant of the reaction and the activation energy of deamination can be calculated.

关 键 词：胞嘧啶 脱氨基 DNA突变 检测方法 

分 类 号：Q523.03[生物学—生物化学]