美国ABC出口商IrtAB进口并减少了真菌菌体
Fabian M Arnold1, Miriam S Weber2, Imre Gonda1
1Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland.
Nature
|April 17, 2020
概括
结核菌使用IrtAB转运器来进口消耗铁的 siderophores. 结构和功能研究显示,IrtAB作为异常的ABC输出者,对病原体的生存至关重要.
科学领域:
- 微生物学
- 结构生物学
- 生物化学
背景情况:
- 结核菌需要 siderophores 细胞内铁的获取和复制.
- 两种 siderophore 类,mycobactin 和 carboxymycobactin 是由 M. 结核菌产生的.
- ATP结合盒 (ABC) 载体 IrtAB 参与了 siderophore 进口.
研究的目的:
- 阐明结核病IRTAB载体的功能和结构.
- 解决IRTAB预测的出口人数与已知的进口人数之间的明显矛盾.
- 研究IrtAB的基质特异性和机制.
主要方法:
- IrtAB的膜复制
- 用X射线结晶学和冷电子显微镜来确定结构.
- 酶ATPase活性测定和体内生长测定.
主要成果:
- IrtAB作为一个ABC出口商来进口菌素.
- 结构分析揭示了使基质进口和铁释放成为可能的独特特征.
- IrtAB表现出对mycobactin而不是对carboxymycobactin的基质偏好.
结论:
- IrtAB是一个专门的 siderophore 进口机器.
- 这项研究提供了一个不寻常的ABC出口商的结构性见解.
- 了解IrtAB的功能可能为M.结核病提供新的治疗点.
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