title: tRNA-independent pretransfer editing by class I leucyl-tRNA synthetase.
abstract: Aminoacyl-tRNA synthetases catalyze the formation of aminoacyl-tRNA in a two-step reaction starting with amino acid activation followed by aminoacyl group transfer to tRNA. To clear mistakes that occasionally occur, some of these enzymes carry out editing activities, acting on the misactivated amino acid (pretransfer editing) or after the transfer on the tRNA (post-transfer editing). The post-transfer editing pathway of leucyl-tRNA synthetase has been extensively studied by structural and biochemical approaches. Here, we report the finding of a tRNA-independent pretransfer editing pathway in leucyl-tRNA synthetases from Aquifex aeolicus. Using a CP1-mutant defective in its post-transfer editing function, we showed that this new editing pathway is distinct from the post-transfer editing site and may occur at the synthetic catalytic site, as recently proposed for other aminoacyl-tRNA synthetases.
authors.affiliation: State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Graduate School of the Chinese Academy of Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhu
authors.forename: Peng
authors.initials: P
authors.lastname: Yao
authors.forename: Min
authors.initials: M
authors.lastname: Tan
authors.forename: Gilbert
authors.initials: G
authors.lastname: Eriani
authors.forename: En-Duo
authors.initials: ED
authors.lastname: Wang
mesh_terms: D001419:Bacteria / Q000201:enzymology* / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D020134:Catalytic Domain / Q000502:physiology; D007935:Leucine-tRNA Ligase / Q000235:genetics / Q000378:metabolism*; D017393:RNA Editing / Q000502:physiology*; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism*; D012343:RNA, Transfer / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D012329:RNA, Bacterial; D012343:RNA, Transfer; D007935:Leucine-tRNA Ligase