将牺牲的DNA修复蛋白N-ada转化为催化甲基三修复酶
Chuan He1, Hua Wei, Gregory L Verdine
1Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, Massachusetts 02138, USA.
Journal of the American Chemical Society
|February 6, 2003
概括
在N-Ada中活性位点残留物Cys38的突变,一种DNA修复蛋白,使其能够利用甲乙醇作为外部试剂,以催化方式修复DNA甲基酸.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- DNA 修复机制的修复机制
背景情况:
- 基因甲基三是有害的DNA添加物,需要修复.
- N-Ada是一种参与DNA修复的蛋白质,通常充当牺牲剂.
研究的目的:
- 在N-Ada.中研究突变活性部位残留物Cys38的功能后果.
- 为了确定N-Ada是否可以被设计为利用外部试剂进行DNA修复.
主要方法:
- 用于改变N-Ada的活性部位残留物Cys38的部位定向突变发生.
- 进行了酶活性测定,以评估DNA甲基酸的修复.
- 为了描述催化机制,进行了动力学分析.
主要成果:
- 在N-Ada中Cys38的突变将其从牺牲性DNA修复蛋白转化为酶.
- 突变的N-Ada酶有效地修复了使用甲乙醇作为外部牺牲试剂的DNA甲基酸.
- 证明了催化修复活性,表明了N-Ada的新机制.
结论:
- 活性部位残留物Cys38对于N-Ada的牺牲DNA修复功能至关重要.
- 通过突变Cys38,工程N-Ada产生了一种多功能DNA修复酶,能够利用外部试剂.
- 这项研究提供了对DNA修复的酶工程和新治疗策略的开发的见解.
相关概念视频
01:08Nucleotide Excision Repair
Overview
01:54Base Excision Repair
One of the common DNA damages is the chemical alteration of single bases by alkylation, oxidation, or deamination. The altered bases cause mispairing and strand breakage during replication. This type of damage causes minimal change to the DNA double helix structure and can be repaired by the base excision repair (BER) pathways. BER corrects damaged DNA sequences by removing the damaged base and restoring the original base sequence using the complementary strand as a template.
The first step of...
The first step of...
01:02Long-patch Base Excision Repair
Since the discovery of the two BER pathways, there has been a debate about how a cell chooses one pathway over the other and the factors determining this selection. Numerous in vitro experiments have pointed out multiple determinants for the sub-pathway selection. These are:
01:08Nucleotide Excision Repair
Overview
01:54Base Excision Repair
One of the common DNA damages is the chemical alteration of single bases by alkylation, oxidation, or deamination. The altered bases cause mispairing and strand breakage during replication. This type of damage causes minimal change to the DNA double helix structure and can be repaired by the base excision repair (BER) pathways. BER corrects damaged DNA sequences by removing the damaged base and restoring the original base sequence using the complementary strand as a template.
The first step of...
The first step of...
01:38Nucleotide Excision Repair
DNA Distortion and Damage
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...