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通过大肠杆菌脂肪乙-CoA脱酶产生内源性过氧化的证据
Chaiyos Sirithanakorn1,2, James A Imlay2
1Division of Molecular and Cellular Medicine, King Mongkut's Institute of Technology Ladkrabang, Faculty of Medicine, Bangkok, Thailand.
PloS one
|October 22, 2024
概括
有氧生物产生反应性氧物种 (ROS). 这项研究表明,脂肪酸代谢,特别是通过A-CoA脱酶 (FadE),显著增加过氧化的产生,影响细胞生长.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 微生物学 微生物学
背景情况:
- 有氧生物产生反应性氧物种 (ROS),如超氧化物和过氧化,这可能会损害细胞组件.
- 细胞拥有抗氧化酶,如超氧化物脱酶,催化酶和过氧化酶,以减轻ROS损伤.
- 主要的细胞内ROS源仍然在很大程度上未被确定,尽管它们在细胞健康中的关键作用.
研究的目的:
- 调查酶,特别是脂肪酸β-氧化中的Acyl-CoA脱酶 (FadE) 的作用,作为细胞内ROS的潜在来源.
- 为了确定脂肪酸的代谢是否对活细胞内的过氧化产生有显著的贡献.
- 评估FadE介导的ROS产生对细胞生长和应激反应的影响.
主要方法:
- 利用缺乏特定过氧化物清除酶的突变菌株来观察 dodecanoic acid 代谢过程中的生长缺陷.
- 在脂肪酸代谢条件下比较了野生型和fadE突变菌株的生长.
- 进行了直接测量,以量化β氧化过程中细胞内过氧化的形成.
主要成果:
- 多德卡诺酸代谢破坏了缺乏过氧化清理酶的菌株的生长.
- 这种生长缺陷在fadE突变体中不存在,这表明FadeE参与了ROS生成.
- 直接测量证实,β-氧化途径放大了细胞内过氧化的形成.
- 具有足够过氧化物清除能力的细胞在多德卡诺酸代谢过程中没有表现出生长缺陷或诱导过氧化物应激反应.
结论:
- 脂肪酸β-氧化,由乙-CoA脱酶 (FadE) 介导,是细胞内过氧化的重要来源.
- 细胞生长和应激反应受到来自代谢途径的ROS生产和抗氧化剂防御能力之间的平衡的影响.
- 需要进行进一步的体外研究,以阐明ROS从FadeE黄素部位释放的特定机制,并确定其天然氧化还原伙伴.
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