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@article{,

title = {Modulation of aminoacylation and editing properties of leucyl-tRNA synthetase by a conserved structural module.},

author = {W Yan and Q Ye and M Tan and X Chen and G Eriani and E D Wang},

url = {http://www.ncbi.nlm.nih.gov/pubmed/25817995?dopt=Abstract},

doi = {10.1074/jbc.M115.639492},

isbn = {25817995},

year  = {2015},

date = {2015-01-01},

journal = {J Biol Chem},

volume = {290},

number = {19},

pages = {12256-12267},

abstract = {A conserved structural module following the KMSKS catalytic loop exhibits α-α-β-α topology in class Ia and Ib aminoacyl-tRNA synthetases. However, the function of this domain has received little attention. Here, we describe the effect this module has on the aminoacylation and editing capacities of leucyl-tRNA synthetases (LeuRSs) by characterizing the key residues from various species. Mutation of highly conserved basic residues on the third α-helix of this domain impairs the affinity of LeuRS for the anticodon stem of tRNALeu, which decreases both aminoacylation and editing activities. Two glycine residues on this α-helix contribute to flexibility, leucine activation and editing of LeuRS from Escherichia coli (EcLeuRS). Acidic residues on the β-strand enhance the editing activity of EcLeuRS and sense the size of the tRNALeu D-loop. Incorporation of these residues stimulates the tRNA-dependent editing activity of the chimeric minimalist enzyme MmLeuRS fused with the connective polypeptide 1 (CP1) editing domain and leucine-specific domain of (LSD) from EcLeuRS. Together, these results reveal the stem contact (SC)-fold to be functional as well as a structural linker between the catalytic site and tRNA binding domain. Sequence comparison of the EcLeuRS SC-fold domain with editing-deficient enzymes suggests that key residues of this module have evolved an adaptive strategy to follow the editing functions of LeuRSs.},

keywords = {aminoacyl tRNA synthetase aminoacylation editing enzyme evolution protein synthesis stem contact fold transfer RNA (tRNA), ERIANI, Unité ARN},

pubstate = {published},

tppubtype = {article}

}