菌体介导的毒素基因的基因间转移
1Kimmel Center for Biology and Medicine, Skirball Institute for Biomolecular Medicine, New York University Medical Center, New York, NY, 10016, USA.
Science (New York, N.Y.)
|January 3, 2009
概括
菌体 (感染细菌的病毒) 可以在不同细菌物种之间转移基因,而不仅仅是在它们内部. 这一发现对人类病原体的进化有重大影响.
科学领域:
- 微生物学 微生物学
- 遗传学 是一个遗传学.
- 进化生物学 进化生物学
背景情况:
- 菌体通常会感染特定的细菌宿主,这导致人们认为遗传交换仅限于物种内部转移.
- 移动遗传元素,包括病原性岛屿,对于细菌的适应性和毒性至关重要.
研究的目的:
- 为了研究由细菌介导的物种间基因转移的潜力.
- 评估葡萄球菌病原性岛屿转移到Listeria monocytogenes的频率.
- 探索菌体介导的基因交换对病原体进化的影响.
主要方法:
- 使用葡萄球菌菌体和Listeria monocytogenes的实验转导试验.
- 在黄金葡萄球菌和L. monocytogenes之间的病原性岛屿转移频率的量化.
- 在生牛奶中模拟菌体治疗条件,以观察物种间的转移.
主要成果:
- 葡萄球菌病原性岛屿和移动元素在高频率转移到Listeria monocytogenes,与物种内部转移相似.
- 葡萄球菌菌体成功转化了L. monocytogenes,尽管没有观察到斑块的形成.
- 在模拟菌体治疗的生牛奶模型中证实了S. aureus和L. monocytogenes之间的病原性岛屿转移.
结论:
- 菌体促进了不同细菌物种之间广泛的遗传信息交换,挑战了以前的假设.
- 这种由菌体介导的物种间基因转移对包括人类病原体在内的细菌病原体的进化有重大影响.
- 这些发现表明菌体在细菌进化和适应中的作用比以前认为的要更广泛.
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