一个新的结合性转子子携带一个自主放大等离子体
Joseph H Vineis1, William S Reznikoff1, Dionysios A Antonopoulos2
1Josephine Bay Paul Center, Marine Biological Laboratory, Woods Hole, Massachusetts, USA.
mBio
|January 23, 2024
概括
在肠道细菌Bacteroides fragilis中,在一个移动遗传元件CTn214上发现了一种新的四环素耐药性基因tetQ. 这种元素可以以圆形的形式存在,提供一致的抗性,或集成到染色体中,其表达受到四环素的调节.
科学领域:
- 微生物学 微生物学
- 遗传学 遗传学 是一个
- 分子生物学分子生物学
背景情况:
- 环素是治疗细菌感染至关重要的广谱抗生素.
- 新兴的四环素耐药基因需要了解它们的机制,转移和对人类健康的影响.
- 肠道微生物组含有各种细菌,包括Bacteroides fragilis,它们可以携带抗生素耐药性基因.
研究的目的:
- 为了研究四环素耐药性基因tetQ在新型结合性转子体CTn214中的基因组安排和表达,在 Bacteroides fragilis.
- 在炎症性肠道疾病的背景下,探索四环素耐药性和基因转移的机制.
主要方法:
- 来自性结肠炎患者的囊样本的枪测序和元基因组读取映射.
- 隔离和培养Bacteroides fragilis菌株的方法.
- 在不同抗生素度下对细菌分离物的基因组和转录组测序.
主要成果:
- 在Bacteroides fragilis中发现了一种携带tetQ的55kbp结合性转子子 (CTn214) .
- CTn214表现出两种不同的基因组安排:集成到染色体中,并作为一个多副本的圆形外染色体元素.
- 含有tetQ的CTn214的圆形形式是构成性表达的,而综合形式的表达是四环素依赖的.
结论:
- CTn214代表了Bacteroides fragilis中四环素耐药性的新机制,涉及染色体集成和tetQ载体循环元素的自主放大.
- 从圆形形式的构成表达可以确保对四环素的持续性核糖体保护.
- 这一发现提供了关于抗生素耐药性病原生物在炎症性肠病患者的出现和持续性的见解.
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