同时存在的细菌氨基酸-tRNA合成酶对应物表现出不同的遗传学背景和与大肠杆菌的功能兼容性
Alexander A Radecki1, Ariana Fantasia-Davis1, Juan S Maldonado1
1Department of Molecular Biology and Biophysics, UConn Health, Farmington, Connecticut, USA.
IUBMB life
|October 17, 2024
概括
许多细菌拥有额外的氨基酸-tRNA合成酶 (aaRS) 基因,但它们的功能尚不清楚. 这项研究发现重复的aaRS基因往往具有不同的起源,在细菌中通常只有一个活跃的基因.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 氨基酸-tRNA合成酶 (aaRSs) 是蛋白质合成的关键酶,催化氨基酸与它们的同源tRNA的附着.
- 虽然通常由单个基因编码,但一些生物体拥有多个aaRS基因拷贝,可能是为了适应生活方式.
- 这些重复的aaRS基因 (对应基因) 的功能往往难以确定,因为它们具有独特的角色和不一致的注释.
研究的目的:
- 调查人类致病细菌中共存的aaRS类型的遗传起源和功能活动.
- 了解识别,分类和预测重复的aaRS基因的作用所面临的挑战.
- 提供对aARS对细菌病原体的仿制物生物意义的见解.
主要方法:
- 进行了对特定的aaRS对应物 (三法尼尔,氨基,氨基和prolyl-tRNA合成酶) 的比较,遗传学和功能分析.
- 在体内进行了功能性表征,使用工程Escherichia coli菌株来评估tRNA氨基化活性.
- 遗传学研究研究了重复的aaRS基因之间的进化关系.
主要成果:
- 重复的aaRS基因通常来自不同的家族遗传背景.
- 在大多数情况下,只有一个共存的aaRS对应物在大肠杆菌中表现出功能性tRNA氨基化活性.
- 另一种对应物经常与大肠杆菌宿主系统不兼容,表明了专门的或非正规的功能.
结论:
- 识别和预测aARS对应器的功能是复杂的,突出说明和分类方面的挑战.
- 这项研究揭示了aARS基因复杂的进化途径及其在细菌病原体生物学中的潜在作用.
- 这项工作为探索不同细菌物种中反复发生的aaRS对比的生理重要性奠定了基础知识.
关键词:
氨基酸-tRNA合成酶的氨基酸.细菌 细菌 细菌是一种细菌.进化 演化 演化 演化 演化 演化 演化 演化基因复制是基因的复制.蛋白质合成 蛋白质合成这是一个tRNARNA.翻译翻译翻译翻译翻译翻译更多相关视频
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