在特定位点重组中的分子组织:菌体HP1整合酶的催化域在2.7A分辨率下
A B Hickman1, S Waninger, J J Scocca
1Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
Cell
|April 18, 1997
概括
惠普1整合酶在Haemophilus influenzae中促进了DNA重组. 它的C端域揭示了一种新的蛋白质折叠,对于结合和催化至关重要,形成反平行二极体.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 遗传学 是一个遗传学.
背景情况:
- HP1整合酶对于将HP1基因组整合到Haemophilus influenzae中至关重要.
- 了解HP1整合酶功能的结构基础是阐明其催化机制的关键.
研究的目的:
- 描述HP1整合酶C端域的结构和功能.
- 为了研究HP1整合酶介导的重组中涉及的分子相互作用.
主要方法:
- 蛋白质表达和净化HP1整合酶C端域.
- 使用X射线晶体学或NMR光谱学进行结构分析.
- 生物化学测试以评估DNA结合和催化活性.
主要成果:
- 分离的C端域 (残留165-337) 进行了表征.
- 这个域表现出一种新的折叠,包括α螺旋,β片和C端尾.
- 确定了关键的催化残留物和二元化接口,揭示了反平行二元形成.
结论:
- HP1整合酶的C端域具有其功能必不可少的独特结构折叠.
- 通过C-终端尾部进行二元化对于指向活性位点进行重组至关重要.
- 这种结构性的洞察力为理解整合和家庭机制提供了基础.
相关概念视频
DNA Helicases
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...
The Replisome
DNA replication is carried out by a large complex of proteins that act in a coordinated matter to achieve high-fidelity DNA replication. Together this complex is known as the DNA replication machinery or the replisome.
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with the...
Homologous Recombination
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
Conservative Site-specific Recombination and Phase Variation
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
Homologous Recombination
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
DNA Bacteriophages
Bacteriophages, or phages, are viruses that specifically infect bacteria, utilizing their genetic material to hijack host cellular machinery for replication. DNA bacteriophages employ single-stranded DNA (ssDNA) or double-stranded DNA (dsDNA) genomes. These phages exhibit diverse replication strategies and host interactions, influencing their ecological roles and applications in biotechnology and medicine.ssDNA BacteriophagesssDNA phages, with their small genomes, utilize unique strategies to...


