The structure of alanyl-tRNA synthetase with editing domain.

ABSTRACT: Alanyl-tRNA synthetase (AlaRS) catalyzes synthesis of Ala-tRNA(Ala) and hydrolysis of mis-acylated Ser- and Gly-tRNA(Ala) at 2 different catalytic sites. Here, we describe the monomer structures of C-terminal truncated archaeal AlaRS, with both activation and editing domains in the apo form, in complex with an Ala-AMP analog, and in a high-resolution lysine-methylated form. The structures show docking of the editing domain to the activation domain opposite from the predicted tRNA-binding surface. Thus, the editing site is positioned >35 A from the activation site, prompting us to model 2 different tRNA complexes: one binding tRNA at the activation site, and the other binding tRNA at the editing site. Interestingly, a gel-shift assay also implies the presence of 2 types of tRNA complex with

SUBMITTER: Sokabe M 

PROVIDER: S-EPMC2708700 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature