title: A covalent adduct between the uracil ring and the active site of an aminoacyl tRNA synthetase.
abstract: A covalent adduct of an aminoacyl tRNA synthetase and uracil nucleoside has been isolated. The enzyme adduct is catalytically inactive; one nucleoside is bound per catalytic site. The release of uridine restores enzyme activity. The nucleoside attaches to a protein segment required for tRNA interaction. The findings add support to concepts of a covalent component for some protein-nucleic acid complexes.
mesh_terms: D000412:Alanine-tRNA Ligase / Q000378:metabolism; D000604:Amino Acyl-tRNA Synthetases / Q000378:metabolism*; D001665:Binding Sites; D004926:Escherichia coli / Q000201:enzymology; D007700:Kinetics; D011485:Protein Binding; D012343:RNA, Transfer / Q000378:metabolism; D014498:Uracil; D014529:Uridine
chemical_list: D014498:Uracil; D012343:RNA, Transfer; D000604:Amino Acyl-tRNA Synthetases; D000412:Alanine-tRNA Ligase; D014529:Uridine