Defects in transient tRNA translocation bypass tRNA synthetase quality control mechanisms.

Quality control mechanisms during protein synthesis are essential to fidelity and cell survival. Leucyl-tRNA synthetase (LeuRS) misactivates non-leucine amino acids including isoleucine, methionine, and norvaline. To prevent translational errors, mischarged tRNA products are translocated 30A from the canonical aminoacylation core to a hydrolytic editing-active site within a completely separate domain.