失去Pde1功能的行为作为一个进化门户,素耐药性在Streptococcus pneumoniae
Carolin M Kobras1, William Monteith2, Sophie Somerville1
1School for Biosciences, Florey Institute for Host-Pathogen Interactions, University of Sheffield, Sheffield S10 2TN, United Kingdom.
概括
新的研究表明,Streptococcus pneumoniae中pde1基因的突变可以导致青素耐药性. 这一发现为这种主要的人类病原体的抗生素耐药性途径提供了新的理解.
科学领域:
- 微生物学 微生物学
- 遗传学 遗传学 是一个
- 进化生物学 进化生物学
背景情况:
- 肺炎链球菌 (Streptococcus pneumoniae) 是一个重要的人类病原体.
- 对贝塔乳酸抗生素 (如青素) 的耐药性日益增加,构成了全球健康威胁.
- 虽然青素结合蛋白 (PBP) 突变会产生高水平的耐药性,但其他遗传因素也参与其中,但不太了解.
研究的目的:
- 为了确定Streptococcus pneumoniae中独立于PBP修饰的新型青素耐药性途径.
- 调查PBP突变之外的遗传因素在赋予青素耐药性的作用.
主要方法:
- 控制的实验室选择实验以确定高频突变.
- 从自然和临床分离物中对超过7200个Streptococcus pneumoniae基因组进行了种群分析.
- 酶活性测定用于评估突变对Pde1功能的影响.
主要成果:
- 在实验室选择中确定了高频率的pde1突变,从而赋予了青素耐药性.
- 对超过7200个基因组的分析证实了pde1位点变异在自然和临床种群中的重要性.
- pde1突变降低了Pde1酶的活性,增加了循环二氨酸单酸盐水平和青素耐药性.
结论:
- 在pde1中发生的快速de novo功能丧失突变代表了向低水平青素耐药性的进化途径.
- 这种遗传变化使细菌能够持续存在并获得进一步的突变以获得高水平的耐药性.
- 确定了一种新的,不依赖于PBP的机制,有助于Streptococcus pneumoniae的抗生素耐药性.
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