在抗万科胺素耐药Enterococcus faecalis的病原性岛内调节毒性
Nathan Shankar1, Arto S Baghdayan, Michael S Gilmore
1nathan-shankar@ouhsc.eduDepartment of Pharmaceutical Sciences, University of Oklahoma Health Sciences Center, PO Box 26901, Oklahoma City, Oklahoma 73190, USA.
Nature
|June 18, 2002
概括
研究人员在常见的肠道细菌Enterococcus faecalis中发现了一个大型致病性岛屿. 这种基因元素在菌株之间微妙地变化,有助于调节毒性,并识别出不对正常肠道功能至关重要的新疾病点.
科学领域:
- 微生物学 微生物学
- 基因组学就是基因组学.
- 传染性疾病 传染性疾病
背景情况:
- 肠球菌是人类正常肠道菌群的一部分.
- 它们也是医院感染的主要原因,通常是抗生素耐药的.
- 之前的研究还没有确定该属的病原性岛屿.
研究的目的:
- 研究Enterococcus faecalis.alis中毒性的遗传基础.
- 识别新的毒性因素和潜在的治疗点.
主要方法:
- 两种不同的Enterococcus faecalis菌株的基因组测序 (医院爆发菌株和美国第一种抗万科米辛分离物).
- 进行比较基因组分析以识别独特的遗传元素.
- 分析已识别的病原性岛内的结构和变异.
主要成果:
- 一个大 (大约. 150 kb) 的病原性岛在两种菌株中都被确定,在Enterococci中以前是未知的.
- 这个岛屿的G+C含量较低,并被终端重复环绕.
- 岛内微妙的高频变化调节了细菌的毒性.
- 该岛上含有已知的毒性因子和在非致病性分离物中罕见的新基因.
结论:
- 肠球菌病原性岛是毒性的一个关键因素.
- 这个岛上的变异使得菌株能够适应并引起感染.
- 岛上的新基因代表了新的抗菌疗法的潜在目标.
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