过氧酸盐还原酶是细菌过氧化素的活性
1Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York 10021, USA.
Nature
|September 23, 2000
概括
过氧化素,就像沙门氏菌型菌中的AhpC一样,可以排毒有害的过氧化酸盐. 这种在细菌中发现的酶活动,保护像DNA这样的细胞分子免受氧化损伤.
科学领域:
- 生物化学 生物化学
- 微生物学 微生物学
- 细胞生物学 细胞生物学
背景情况:
- 氧化 (NO) 和超氧化 (O2-) 反应形成过氧化 (OONO-).
- 过氧酸盐是一种具有氧化,炎症,突变和细胞毒性潜力的活性分子.
- 应对过氧酸盐的细胞机制对于理解NO的生物效应至关重要.
研究的目的:
- 为了研究细胞是否具有能够排毒过氧酸盐的酶.
- 探索氧酸盐在氧酸盐排毒中的氧素的潜在作用.
主要方法:
- 酶测定使用来自沙门氏菌的氧化 (alkylhydroperoxide) 减少酶子单元C (AhpC) 来进行.
- 测试AhpC在排毒过氧酸盐中的催化活性.
- 将结果与来自Mycobacterium tuberculosis和Helicobacter pylori的过氧素进行比较.
主要成果:
- 沙门氏菌的AhpC被证明可以以催化方式将过氧酸盐解毒为酸盐.
- 这种解毒发生得很快,防止对旁观分子 (如DNA) 的损伤.
- 在Mycobacterium tuberculosis和Helicobacter pylori的过氧化素中观察到类似的过氧化缩酶活性.
结论:
- 氧化素,特别是AhpC,具有氧酸盐还原酶活性.
- 这种酶活性足以保护细胞组件免受过氧酸盐诱导的损伤.
- 过氧酸盐还原酶活性可能是细菌属中广泛存在的解毒机制.
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