EVOLUTION OF ESSENTIAL TRANSLATIONAL PATHWAYS IN ARCHAEA

古生菌基本翻译途径的进化

• 批准号: 6138562
• 负责人: DIETER SOLL
• 金额: $ 20.74万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-01-01 至 2001-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6138562
• 关键词: Archaea; RNA biosynthesis; aminoacyl tRNA; biochemical evolution; genetic translation

(adapted from investigator's abstract): This proposal will investigate a number of unique components of the archael translation apparatus which are essential for the faithful decoding of mRNA into protein. Correctly amino- aceylated tRNAs are required for accurate ribosomal translation. They are generally believed to be provided solely by the aminoacyl-tRNA synthetases, a ubiquitous and highly conserved family of enzymes found throughout the living kingdom. However, many organisms and some organelles lack at least one aminoacyl-tRNA synthetase, glutaminyl-tRNA synthetase. In these organisms and organelles Gln-tRNA is formed by the amidation of glutamate mis acylated to t-RNA Gln. The P.I. has recently shown that a comparable pathway also exists for the synthesis of Asn-tRNA in Archaea. Thus amino acid transformations, previously only associated with intermediary metabolism, are a key requirement for translational fidelity particularly in Archaea. A second unique feature of archael aminoacyl-tRNA formation is the use of enzymes distinct from any yet found in either eubacteria or eukaryotes to generate lysyl-tRNA and cysteinyl-tRNA.

（改编自研究者的摘要）：该提案将调查 archael 翻译装置的许多独特组件是 对于将 mRNA 忠实地解码为蛋白质至关重要。正确氨基- 准确的核糖体翻译需要乙酰化 tRNA。他们是 一般认为仅由氨酰基-tRNA 提供 合成酶，一个普遍存在且高度保守的酶家族 整个生命王国。然而，许多生物体和一些细胞器 缺乏至少一种氨酰-tRNA合成酶、谷氨酰胺酰-tRNA合成酶。 在这些生物体和细胞器中，Gln-tRNA 是通过酰胺化形成的 谷氨酸错误酰化为 t-RNA Gln。 P.I.最近表明，一个 古细菌中也存在类似的 Asn-tRNA 合成途径。 因此，氨基酸转化以前仅与 中间代谢是翻译保真度的关键要求 特别是在古细菌中。古菌氨酰-tRNA 的第二个独特特征 形成是使用与任何一种中尚未发现的酶不同的酶 真细菌或真核生物产生赖氨酰-tRNA和半胱氨酰-tRNA。