The catalytic flexibility of tRNAIle-lysidine synthetase can generate alternative tRNA substrates for isoleucyl-tRNA synthetase.

ABSTRACT: Bacteria decode the isoleucine codon AUA using a tRNA species that is posttranscriptionally modified at the wobble position of the anticodon with a lysine-containing cytidine derivative called lysidine. The lysidine modification of tRNA(Ile2) is an essential identity determinant for proper aminoacylation by isoleucyl tRNA synthetase (IleRS) and codon recognition on the ribosome. The ATP- and lysine-dependent formation of lysidine is catalyzed by tRNA(Ile)-lysidine synthetase. Using the purified recombinant enzyme from Escherichia coli and an in vitro transcribed tRNA substrate, we have confirmed that lysidine modification is both necessary and sufficient to convert tRNA(Ile2) into a substrate for IleRS. A series of lysine analogs were tested as potential inhibitors during the mechanistic c

SUBMITTER: Salowe SP 

PROVIDER: S-EPMC2665086 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature