尤格莱娜的非典型呼吸链适应了 discoidal 形和灵活的新陈代谢
Zhaoxiang He1, Mengchen Wu1, Hongtao Tian1
1Department of Biophysics and Department of Critical Care Medicine of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China.
Nature communications
|February 22, 2024
概括
高分辨率的冷电磁结构显示了Euglena gracilis的形状.
科学领域:
- 生物化学和结构生物学.
- 单核细胞生物学 单核细胞生物学
- 分子和进化生物学分子和进化生物学
背景情况:
- 优格丽娜 (Euglena gracilis) 是真核超群迪斯科巴 (Discoba) 的模型生物,其中包括重要的寄生虫.
- 由于缺乏结构数据,其独特的电子传输链和代谢策略尚不清楚.
- 了解迪斯科巴的生物能量对于填补真核生物进化树上的空白至关重要.
研究的目的:
- 确定高分辨率冷电子显微镜 (cryo-EM) 结构的Euglena gracilis'呼吸体 (复合体I + III2 + IV) 和一个超复合体 (III2 + IV2).
- 阐明Euglena非典型电子运输链及其代谢适应的结构基础.
- 提供关于真核生物生物能学的进化背景的见解.
主要方法:
- 使用高分辨率冷电子显微镜 (cryo-EM) 来确定结构.
- 在Euglena的盘状晶体中分析呼吸和超复杂的安排.
- 详细检查复杂I结构及其与ubiquinone的相互作用.
主要成果:
- 报告了第一个Euglena呼吸体 (I + III2 + IV) 和超复杂体 (III2 + IV2) 的高分辨率冷EM结构.
- 在I复合体上确定了一种新的脂肪酸合成域,解释了其非典型的子单元组成.
- 揭示了复合物重新排列以适应膜曲率,并且复合物I被限制的ubiquinone访问禁用.
结论:
- 这些结构发现提供了对Euglena独特的电子运输链及其代谢适应的详细了解.
- 这些见解填补了迪斯科巴血统中真核生物能量学结构知识的重大差距.
- 这项研究为开发治疗治疗因euglenozoan寄生虫引起的感染提供了潜在的目标.
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