Functional segregation of a predicted "hinge" site within the beta-strand linkers of Escherichia coli leucyl-tRNA synthetase.

ABSTRACT: Some aminoacyl-tRNA synthetases (AARSs) employ an editing mechanism to ensure the fidelity of protein synthesis. Leucyl-tRNA synthetase (LeuRS), isoleucyl-tRNA synthetase (IleRS), and valyl-tRNA synthetase (ValRS) share a common insertion, called the CP1 domain, which is responsible for clearing misformed products. This discrete domain is connected to the main body of the enzyme via two beta-strand tethers. The CP1 hydrolytic editing active site is located approximately 30 A from the aminoacylation active site in the canonical core of the enzyme, requiring translocation of mischarged amino acids for editing. An ensemble of crystal and cocrystal structures for LeuRS, IleRS, and ValRS suggests that the CP1 domain rotates via its flexible beta-strand linkers relative to the main body along va

SUBMITTER: Mascarenhas AP 

PROVIDER: S-EPMC2905381 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature