对pT181等离子体启动蛋白的复制特异性失活
1Department of Plasmid Biology, Public Health Research Institute, New York, NY 10016.
概括
黄金葡萄球菌等离子体复制包括将DNA片段附在RepC蛋白上. 这会使蛋白质失活,调节等离子体DNA复制,同时控制合成.
科学领域:
- 分子生物学分子生物学
- 微生物学 微生物学
- 遗传学 是一个遗传学.
背景情况:
- 黄金葡萄球菌等离子体pT181通过滚动圆机制复制.
- 等离子体复制启动由等离子体编码的启动蛋白RepC控制.
研究的目的:
- 为了研究黄金葡萄球菌等离子体pT181复制的调节机制.
- 了解启动蛋白RepC在复制控制中的作用.
主要方法:
- 在复制过程中对一个寡核酸与RepC蛋白的共价附着的分析.
- 修改后的RepC蛋白的功能性质的表征.
主要成果:
- 复制是伴随着对一个~12-残留的寡度氧核酸对一个RepC子单元的共价附着.
- 由此产生的RepC异构聚合物与等离子体DNA序列3'对位进行共连接.
- 与未经修改的RepC相比,修改后的RepC蛋白显示出降低的拓酶和复制活动.
结论:
- 启动蛋白RepC的复制后无活化是等离子体DNA复制中的关键调节步骤.
- 塑复制的调节包括对RepC合成的控制和其复制后的失活.
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