生物化学和遗传学研究定义了甲基转移酶在甲生和甲类古生物中的功能
Kaleb Boswinkle1, Thuc-Anh Dinh1, Kylie D Allen1
1Department of Biochemistry, Virginia Tech, Blacksburg, VA, United States.
Frontiers in microbiology
|December 11, 2023
概括
甲基转移酶 (MTTases) 是重要的酶. 这项研究研究了古老的MTTases,揭示了它们在tRNA修饰和产生特定的甲基氨酸衍生物中的作用.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 酶学 是一种酶学.
背景情况:
- 甲基thiotransferases (MTTases) 是激进的S-adenosylmethionine酶,可催化甲基thio组的添加.
- 这些酶对于在所有生命领域的tRNA中产生2-甲基腺素 (ms2A) 衍生物至关重要.
- 虽然已知细菌和真核生物中的MTTase功能,但古老的MTTase及其基质特异性仍未得到充分研究.
研究的目的:
- 为了研究古代MTTases的酶活性和基质特异性.
- 阐明MTTases在古生物中的tRNA修饰中的作用,特别是在甲基生物中.
- 描述MtaB家族MTTases在古老tRNA修饰中的功能.
主要方法:
- 在*Ca.的MTTases上进行了体外酶分析. 甲醇菌 (ANME) 和甲醇菌 (Methanocaldococcus jannaschii) 是一种植物.
- 分析了N-threonylcarbamoyladenosine (t6A) 和N-hydroxynorvalylcarbamoyladenosine (hn6A) 的甲基化作用.
- 在 *Methanosarcina acetivorans* 中产生了一种基因删除突变 (MA1153),以研究tRNA修饰.
主要成果:
- 来自ANME和*M. jannaschii*的古老MTTases在体外表现出活性,催化了ms2t6A和ms2hn6A的形成.
- 在指数增长过程中, *Methanosarcina acetivorans* 产生 ms2hn6A,但不能检测到 ms2t6A.
- 在*M. acetivorans*中删除MA1153基因导致ms2A修饰的缺失,证实了MtaB家族的MTTase功能.
结论:
- 考古MTTases能够甲基化t6A和hn6A残留物.
- 在古生物中,MtaB家族的MTTase负责在精选的tRNA中产生ms2hn6A修饰核酸.
- 这项研究为考古时代tRNA修饰和MTTase功能的研究不足的领域提供了新的见解.
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