在真菌细菌中转换抗生素耐药性元素
1Unité de Genie Microbiologique (URA 209 du CNRS), Institut Pasteur, Paris, France.
Nature
|June 21, 1990
概括
研究人员确定了一个新的遗传区域,在Mycobacterium fortuitum中赋予了硫胺耐药性. 这种元素与插入序列相伴,可以转移到菌根菌的染色体内,为研究毒性提供了新的途径.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 细菌的抗生素耐药性通常由等离子体和可转移元素介导.
- 菌根菌表现出对许多抗生素的固有耐药性,通常归因于它们的细胞壁结构.
- 虽然真菌细菌中存在抗生素修饰酶,但具体的耐药基因以前没有被分离出来.
研究的目的:
- 隔离和鉴定Mycobacterium fortuitum抗生素耐药性的遗传决定因素.
- 为了研究菌根菌中的硫胺耐药性的遗传基础.
- 为了探索菌根菌中的基因操纵潜力.
主要方法:
- 隔离,克隆和测序来自M. fortuitum的硫胺抗性区域.
- 同性学搜索以确定相关的遗传元素 (例如,整合酶基因,插入序列).
- 在与之相关的快速生长物种Mycobacterium smegmatis中进行转换分析.
主要成果:
- 一个在M.fortuitum中赋予硫胺耐药性的遗传区域被成功分离和测序.
- 这一区域包含一个开放的读取框架,与Tn21家族转位子中发现的特定位点整合酶相同.
- 电阻元件的旁边是880bp的重复序列,类似于IS6家族插入元件.
- 插入元件表明转移到M. smegmatis的各种染色体位置.
结论:
- 这种特征的遗传元素代表了菌根菌中抗生素耐药性的新机制.
- 整合酶和可转移元素的存在表明,一个负责耐药性的移动遗传元素.
- 这一发现有助于开发转子子突变发生的工具,用于分析菌根菌的毒性和其他生物过程.
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