在Listeria monocytogenes中研究inlA的遗传多态性和功能,与Listeria monocytogenes中过早停止子
Xin Liu1, Binru Gao1, Zhuosi Li1
1School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
Foods (Basel, Switzerland)
|September 13, 2025
概括
在Listeria monocytogenes病毒性基因inlA中发生过早停止密码子 (PMSC) 突变在食品分离物中很常见,并与特定的克隆复合体 (CC) 类型相关. 这些突变显著影响细菌的附着性和侵入性,特别是在高毒性菌株中.
科学领域:
- 食品微生物学 食品微生物学
- 细菌病原体的产生
- 基因组学就是基因组学.
背景情况:
- 李斯特菌 (Listeria monocytogenes) 是一种重要的食物传播病原体,引起李斯特菌病.
- inlA基因对于L. monocytogenes侵入宿主细胞至关重要.
- 在inlA中发生的过早停止密码子 (PMSC) 突变可以减弱病毒性.
研究的目的:
- 在L. monocytogenes的食物分离物中,对包括PMSC突变在内的lA变异进行表征.
- 调查inlA完整性和PMSC突变对细菌毒性的功能影响.
- 为了确定inlA变异,克隆复合体 (CC) 类型和毒性之间的关联.
主要方法:
- 在546L中的inlA的表征.单细胞原体来自上海的食品分离物.
- 使用同源重组构建一个inlA删除的菌株.
- 在Caco-2细胞中对各种L. monocytogenes菌株进行完整或突变的inlA病毒性测试 (粘附和入侵测试).
主要成果:
- 36.1%的食品分离物中含有与PMSC的1A,主要在CC9和CC121.
- inlA删除没有影响细菌耐药性,但显著影响了粘附性和侵入性.
- 在inlA中的PMSC突变在高毒性CC型 (例如CC8,CC7) 中大大促进了粘附和侵入,但在低毒性菌株中却没有.
结论:
- inlA的完整性和PMSC突变的存在以CC类型依赖的方式影响L. monocytogenes的毒性.
- 过早终止inlA可以增强特定高风险L. monocytogenes菌株的毒性.
- 这项研究为了解INLA介导的致病机制提供了基础.
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