菌体的定向进化:被多产的菌体阻碍了
Tracey Lee Peters1,2, Jacob Schow2, Emma Spencer2
1Institute for Modeling Collaboration and Innovation, University of Idaho, Moscow, Idaho, USA.
Applied and environmental microbiology
|October 30, 2024
概括
前体,而不是进化的菌体,在一个定向进化实验中引起了明显的宿主范围扩张. 这凸显了在菌体研究中查菌体的必要性,特别是对于治疗应用.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 定向进化经常用于扩大菌体宿主范围,准耐药细菌.
- 这个过程涉及菌体在细菌宿主上的代传播,理论上产生进化的菌体.
- 然而,细菌菌体可以污染菌体制剂,使实验结果复杂化.
研究的目的:
- 为了研究在使用Appelmans协议的定向进化实验中观察到的宿主范围扩张.
- 为了确定 * Pseudomonas aeruginosa * 菌体-宿主系统中意想不到的宿主范围扩张的来源.
- 评估菌体对定向进化实验和菌体疗法开发的影响.
主要方法:
- 对菌体定向进化的Appelmans协议的实施.
- 菌体尾酒在多种*Pseudomonas aeruginosa*菌株上的传播.
- 隔离的菌体和宿主菌株的测序,以确定遗传组件.
- 种内对抗性测试检测出抑制性活动和prophage存在.
主要成果:
- 观察到的宿主范围的快速扩张归因于*Casadabanvirus*的传播,而不是进化的菌体.
- 导体起源于实验早期包含的溶解性宿主,并感染了多个细菌宿主.
- 在测序的样本中,其中一半的样本中存在菌体,但在实验条件下没有演变的迹象.
- 跨物种对抗性测试对于检测prophage的存在非常有用.
结论:
- 前体可以显著影响定向进化实验,导致关于体适应的错误结论.
- 对菌体的遗传验证和对菌体的查至关重要,特别是在菌体治疗应用中.
- 在实验设计中,物种内对抗性测试是基线评估和菌体检测的宝贵工具.
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