塑体的分子特征和流行率,共同携带mcr和ESBL基因
K M G Houkes1,2, V Weterings3, J J Verweij2
1Microvida, Laboratory of Medical Microbiology, Amphia Hospital, Breda, Netherlands.
Microbial genomics
|July 29, 2025
概括
携带扩展谱β-乳糖酶 (ESBLs) 和胆固醇抗性 (mcr) 基因的耐多药性肠道细菌是一个主要威胁. 这项研究发现,5.9%的ESBL-E分离物在IncHI等离子体上含有mcr基因,主要是mcr-9,这表明单一的引入事件和广泛传播.
科学领域:
- 微生物学 微生物学
- 遗传学 是一个遗传学.
- 公共卫生 公共卫生
背景情况:
- 耐多药性肠道细菌,特别是具有扩展谱β-乳糖酶 (ESBLs) 和移动胆固醇抗性 (mcr) 基因的肠道细菌,对全球健康构成重大挑战.
- 这些耐药细菌可能导致难以治疗的感染,需要对它们的遗传元素和传播模式有更深入的了解.
研究的目的:
- 在荷兰医院环境中调查ESBL和mcr基因共同携带的肠杆菌的流行情况.
- 描述携带ESBL和mcr基因的等离子体,包括它们的遗传关系和进化史.
主要方法:
- 使用已建立的实验室协议对产生ESBL的肠杆菌 (ESBL-E) 隔离物进行mcr基因的查.
- 全基因组测序 (长读和短读) 用于识别和表征具有抗性基因的等离子体.
- 生物信息学分析包括AMRFinderPlus,PlasmidFinder,SNP分析和家族遗传推断 (BEAST) 以评估等离子体多样性和进化关系.
主要成果:
- 在188个选的ESBL-E分离物中,11个 (5.9%) 含有mcr基因,其中mcr-9是最常见的.
- 所有携带ESBL和mcr基因的等离子体都属于IncHI不兼容组,携带mcr-9和/或mcr-4.3,以及blaCTX-M-9和/或blaSHV-12.
- 遗传学和SNP分析表明研究等离子体之间的多样性有限,这表明单一的引入事件和随后的传播,估计最近的共同祖先在1986年至2008年之间出现.
结论:
- 肠杆菌中ESBL和mcr基因的同时存在是一个有形的威胁,mcr-9在这个荷兰医院中是一个重要的贡献者.
- 限定的等离子体多样性表明,这些共存等离子体的单一引入事件,随后广泛传播.
- 与mcr-9相比,ESBL基因的移动性似乎更为近期,突出显示了抗菌素耐药性的正在进行的进化动态.
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