差异基因表达分析表明,对头素的耐药性是Clostridioides difficile菌株630固有的
Lara A Turello1, Amber Consul1, Christopher Yip1
1Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, Las Vegas, NV, USA.
The Journal of antibiotics
|December 13, 2024
概括
由于抗生素耐药性,Clostridioides difficile感染 (CDI) 越来越令人担忧. 这项研究发现,像blaCDD和ABC载体这样的关键基因,虽然被类素调高,但不会在C. difficile中产生抗性.
科学领域:
- 微生物学 微生物学
- 基因组学就是基因组学.
- 抗生素耐药性 抗生素耐药性
背景情况:
- 困难菌感染 (CDI) 是一种严重的医院感染,因抗生素耐药性增加而恶化.
- 类抗生素是一类β-乳酸抗生素,与较高的CDI风险和C. difficile耐药性有关.
- 了解C. difficile中抗素耐药性的遗传基础对于开发有效治疗方法至关重要.
研究的目的:
- 在暴露于类素后,调查Clostridioides difficile菌株630中假定抗生素耐药性基因的作用.
- 确定负责C. difficile.中抗素耐药性的特定基因.
- 为了分析不同氨酸治疗下抗性基因的表达模式.
主要方法:
- 对C. difficile菌株630的基因组分析,以确定31个假定的β-乳酸盐耐药基因.
- 野生型和突变的C. difficile菌株暴露于塞福西丁和其他类素 (塞夫拉丁,塞夫塔西迪姆,塞费皮姆).
- 转录组分析和基因删除研究,以评估基因表达和在抗生素耐药性中的功能作用.
主要成果:
- 很少有假定的抗生素耐药性基因在素暴露时过度表达,blaCDD显示出~600倍的上调调节.
- 删除blaCDD或vanY并没有改变类素的敏感性.
- 一种异构体的ABC转运体 (CD630_04590和CD630_04600) 常见上调,但其删除突变仍然具有抗生素耐药性.
结论:
- 尽管有显著的上调,但blaCDD基因似乎没有参与C. difficile菌株630的头类素耐药性.
- 鉴定到的ABC载体 (CD630_04590/CD630_04600) 似乎也没有在素耐药性中发挥直接作用.
- 在C. difficile中产生抗素的机制尚不完全理解,需要进一步研究.
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