UCLA

The threonyl-tRNA synthetase is an enzyme that catalyzes the attachment of the amino acid threonine to the threonyl-tRNA so that protein synthesis at the ribosome can occur. In order to maintain translational fidelity, this tRNA synthetase must employ an editing function that is structurally and functionally separate from this enzyme's aminoacylation capacity. Here, we studied the importance editing function of the Bacillus subtilis threonyl synthetase, ThrRS, by making a single amino acid substitution in the separate editing domain. The data in this study suggest that disrupting editing function in the major B. subtilis ThrRS, thrS, is toxic to the cells under normal growth conditions. A future goal in this project is to study the effect of knocking out the editing function of the minor B. subtilis ThrRS, thrZ.