在临床Carbapenemase产生C.C.中出现的FosA3 的朋友们
Vittoria Mattioni Marchetti1, Irene Venturelli2, Tiziana Cassetti2
1Microbiology and Clinical Microbiology Unit, Scienze Clinico, Chirurgiche, Diagnostiche, Pediatriche (SCCDP) Department, University of Pavia, Pavia, Italy.
Frontiers in cellular and infection microbiology
|September 9, 2024
概括
多药耐药细菌中的斯福米辛耐药性正在增加. 研究人员在Citrobacter freundii中发现了FosA3酶,这是一种低风险的病原体,强调了对抗生素耐药机制的持续监测的必要性.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 抗微生物耐药性 抗微生物耐药性
背景情况:
- 菌素 (FOS) 对抗多药耐药肠道细菌至关重要,但其有效性正在下降.
- A酶的患病率,特别是在像Citrobacter freundii这样的低风险病原体中,仍未得到充分研究.
研究的目的:
- 来自意大利的Citrobacter freundii分离物,用于对一种生产碳烯酶和FosA的分子特征进行鉴定.
- 为了研究这种临床隔离物中菌素耐药性的遗传基础.
主要方法:
- 全基因组测序 (WGS) 用于基因组和抗体分析.
- 抗微生物敏感性测试,包括斯福米辛最小抑制度 (MIC) 的确定.
- 移动遗传元素的等离子体分析和表征.
主要成果:
- 一个2023年分离物,AK867,表现出广泛耐药性 (XDR) 概况,只对素敏感.
- 据WGS发现,该分离物属于ST116,并含有fosaA3,blaKPC-2和blaVIM-1基因.
- fosA3基因位于一种结合性pKPC-CAV1312等离子体内的新型复合转子体上.
结论:
- 这项研究报告了FosA3生产在临床碳烯酶产生Citrobacter freundii ST116隔离物中的第一个实例.
- 肠道细菌中FosA3酶的发病率增加,包括像C. freundii这样的低毒性物种,对色胺的有效性构成越来越大的威胁.
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