Structural basis for anticodon recognition by discriminating glutamyl-tRNA synthetase
Structural basis for anticodon recognition by discriminating glutamyl-tRNA synthetase
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DOI：
10.1038/84927
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发表时间：
2001-03-01
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影响因子：
--
通讯作者：
Yokoyama, S
中科院分区：
文献类型：
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作者：
Sekine, S;Nureki, O;Yokoyama, S
Glutamyl-tRNA synthetases (GluRSs) are divided into two distinct types, with regard to the presence or absence of glutaminyl-tRNA synthetase (GlnRS) in the genetic translation systems. In the original 19-synthetase systems lacking GlnRS, the 'non-discriminating' GluRS glutamylates both tRNA(Glu) and tRNA(Gln) In contrast, in the evolved 20-synthetase systems with GlnRS, the 'discriminating' GluRS aminoacylates only tRNA(Glu). Here we report the 2.4 Angstrom resolution crystal structure of a 'discriminating' GluRS.tRNA(Glu) complex from Thermus thermophilus. The GluRS recognizes the tRNA(Glu) anticodon bases via two a-helical domains, maintaining the base stacking. We show that the discrimination between the Glu and Gin anticodons ((YUC36)-Y-34 and (34)YUG(36), respectively) is achieved by a single arginine residue (Arg 358). The mutation of Arg 358 to Gin resulted in a GluRS that does not discriminate between the Glu and Gin anticodons. This change mimics the reverse course of GluRS evolution from anticodon 'non-dicsriminating' to 'discriminating'.
