RecBCD酶是一种双极DNA化酶
Mark S Dillingham1, Maria Spies, Stephen C Kowalczykowski
1Section of Microbiology, Center for Genetics and Development, University of California, Davis, California 95616, USA.
Nature
|June 20, 2003
概括
大肠杆菌RecBCD酶使用两个DNA螺旋酶,RecB和RecD,在相反的方向一起工作. 这种双引擎机制解释了RecBCDD.
科学领域:
- 分子生物学分子生物学
- 酶学 是一种酶学.
- 修复DNA修复DNA的修复
背景情况:
- 大肠杆菌 RecBCD 是DNA修复中的一个关键酶.
- 它处理双链断裂以获得同源重组.
- 已知RecB子单元具有3'到5'酶活性.
研究的目的:
- 为了研究RecD子单元的酶活性.
- 阐明由RecBCD全酶解的DNA解的机制.
主要方法:
- 净化RecD蛋白质的纯化.
- 用完整和突变的RecBCD进行酶活性测定.
- 进行DNA转位和解研究.
主要成果:
- 纯化的RecD蛋白显示5'至3'DNA基酶活性.
- 在完整的RecBCD酶中,RecB和RecD酶都活跃.
- 即使RecB或RecD发生突变,RecBCD仍然对DNA解保持活跃.
结论:
- RecBCD通过双极转位模型发挥作用.
- 两个DNA螺旋 (RecB和RecD) 在相同的方向移动,但与相反的极性.
- 这种机制解释了RecBCD在DNA修复中的高速,过程性和功能.
相关概念视频
DNA Helicases
23.9K
DNA unwinding helicase enzymes are a type of motor protein. Motor proteins can translocate along filaments or polymers using energy generated from ATP hydrolysis. Helicases are involved in all the important cellular processes where DNA unwinding is required, such as DNA replication, repair, recombination, and transcription. They are present in all living organisms, but vary in their structure, function, and mechanism of action. For example, in prokaryotes, DnaB helicase binds and translocates...
23.9K
DNA Replication
58.7K
DNA replication involves the separation of the two strands of the double helix, with each strand serving as a template from which the new complementary strand is copied. After replication, each double-stranded DNA includes one parental or “old” strand and one “new” strand. This is known as semiconservative replication. The resulting DNA molecules have the same sequence and are divided equally into the two daughter cells.
Replication in Prokaryotes
DNA replication...
Replication in Prokaryotes
DNA replication...
58.7K
The DNA Replication Fork
40.6K
An organism’s genome needs to be duplicated in an efficient and error-free manner for its growth and survival. The replication fork is a Y-shaped active region where two strands of DNA are separated and replicated continuously. The coupling of DNA unzipping and complementary strand synthesis is a characteristic feature of a replication fork. Organisms with small circular DNA, such as E. coli, often have a single origin of replication; therefore, they have only two replication...
40.6K
Bipolar Disorder
646
Bipolar disorder is a chronic mental health condition marked by significant mood fluctuations, including episodes of mania and depression. Elevated energy levels, heightened mood or irritability, impulsive behavior, reduced sleep needs, rapid speech, racing thoughts, inflated self-esteem, and distractibility characterize mania. Individuals with bipolar disorder often alternate between depressive and manic states, with periods of emotional stability lasting an average of six months to a year.
646
Enzymes
93.9K
Inside living organisms, enzymes act as catalysts for many biochemical reactions involved in cellular metabolism. The role of enzymes is to reduce the activation energies of biochemical reactions by forming complexes with its substrates. The lowering of activation energies favor an increase in the rates of biochemical reactions.
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
Enzyme deficiencies can often translate into life-threatening diseases. For example, a genetic abnormality resulting in the deficiency of the enzyme G6PD...
93.9K
Bipolar Junction Transistor
1.5K
Bipolar Junction Transistors (BJTs) are essential elements in electronic circuits, playing a crucial role in the functionality of amplifiers, memories, and microprocessors. These transistors can be designed as NPN or PNP based on their doping patterns. They consist of three layers: the emitter, base, and collector. The configuration of these layers and their respective doping levels—with N-type or P-type impurities—define the transistor's type and its operational...
1.5K


