{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Swairjo MA"],"funding":["NIGMS NIH HHS"],"pagination":["988-93"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC545860"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["102(4)"],"pubmed_abstract":["The genetic code is fixed in aminoacylation reactions catalyzed by aminoacyl-tRNA synthetases. Amino acid discrimination occurs at two sites: one for amino acid activation and aminoacylation and one for editing misactivated amino acids. Although the active site sieves out bulkier amino acids, misactivation occurs with substrates whose side chains are smaller than the cognate one. Paradoxically, although alanyl-tRNA synthetase activates glycine as well as alanine, the sterically larger (than alanine) serine is also misactivated. Here, we report crystal structures of an active fragment of Aquifex aeolicus alanyl-tRNA synthetase complexed, separately, with Mg2+-ATP, alanine, glycine, and serine. Ala and Gly are bound in similar orientations in a side-chain-accommodating pocket, where alpha-am"],"journal":["Proceedings of the National Academy of Sciences of the United States of America"],"pubmed_title":["Breaking sieve for steric exclusion of a noncognate amino acid from active site of a tRNA synthetase."],"pmcid":["PMC545860"],"funding_grant_id":["GM 15539","R01 GM015539"],"pubmed_authors":["Schimmel PR","Swairjo MA"],"additional_accession":[]},"is_claimable":false,"name":"Breaking sieve for steric exclusion of a noncognate amino acid from active site of a tRNA synthetase.","description":"The genetic code is fixed in aminoacylation reactions catalyzed by aminoacyl-tRNA synthetases. Amino acid discrimination occurs at two sites: one for amino acid activation and aminoacylation and one for editing misactivated amino acids. Although the active site sieves out bulkier amino acids, misactivation occurs with substrates whose side chains are smaller than the cognate one. Paradoxically, although alanyl-tRNA synthetase activates glycine as well as alanine, the sterically larger (than alanine) serine is also misactivated. Here, we report crystal structures of an active fragment of Aquifex aeolicus alanyl-tRNA synthetase complexed, separately, with Mg2+-ATP, alanine, glycine, and serine. Ala and Gly are bound in similar orientations in a side-chain-accommodating pocket, where alpha-am","dates":{"release":"2005-01-01T00:00:00Z","publication":"2005 Jan","modification":"2025-04-19T11:29:36.558Z","creation":"2019-03-27T01:08:32Z"},"accession":"S-EPMC545860","cross_references":{"pubmed":["15657145"],"doi":["10.1073/pnas.0409024102"]}}