两种拓扑结构不相关的赖氨酰 - tRNA合成酶的功能趋同。

Functional convergence of two lysyl-tRNA synthetases with unrelated topologies.

作者信息

Terada Takaho, Nureki Osamu, Ishitani Ryuichiro, Ambrogelly Alexandre, Ibba Michael, Söll Dieter, Yokoyama Shigeyuki

机构信息

RIKEN Genomic Sciences Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan.

出版信息

Nat Struct Biol. 2002 Apr;9(4):257-62. doi: 10.1038/nsb777.

DOI:10.1038/nsb777

PMID:11887185

Abstract

Lysyl-tRNA can be synthesized by both a class I (LysRS-I) and a class II (LysRS-II) lysyl-tRNA synthetase. The crystal structure of LysRS-I from Pyrococcus horikoshii at 2.6 A resolution reveals extensive similarity with glutamyl-tRNA synthetase (GluRS). A comparison of the structures of LysRS-I and LysRS-II in complex with lysine shows that both enzymes use similar strategies for substrate recognition within unrelated active site topologies. A docking model based upon the GluRS-tRNA complex suggests how LysRS-I and LysRS-II can recognize the same molecular determinants in tRNALys, as shown by biochemical results, while approaching the acceptor helix of the tRNA from opposite sides.

摘要

赖氨酰 - tRNA可由I类（LysRS - I）和II类（LysRS - II）赖氨酰 - tRNA合成酶合成。来自嗜热栖热菌的LysRS - I的晶体结构在2.6埃分辨率下显示出与谷氨酰 - tRNA合成酶（GluRS）有广泛的相似性。对与赖氨酸结合的LysRS - I和LysRS - II的结构比较表明，两种酶在不相关的活性位点拓扑结构内使用相似的底物识别策略。基于GluRS - tRNA复合物的对接模型表明，LysRS - I和LysRS - II如何能够识别tRNALys中的相同分子决定因素，正如生化结果所示，同时从相反的两侧接近tRNA的受体螺旋。