Hydrolysis of non-cognate aminoacyl-adenylates by a class II aminoacyl-tRNA synthetase lacking an editing domain.
Aminoacyl-tRNA synthetases, a group of enzymes catalyzing aminoacyl-tRNA formation, may possess inherent editing activity to clear mistakes arising through the selection of non-cognate amino acid. It is generally assumed that both editing substrates, non-cognate aminoacyl-adenylate and misacylated tRNA, are hydrolyzed at the same editing domain, distant from the active site. Here, we present the first example of an aminoacyl-tRNA synthetase (seryl-tRNA synthetase) that naturally lacks an editing domain, but possesses a hydrolytic activity toward non-cognate aminoacyl-adenylates. Our data reveal that tRNA-independent pre-transfer editing may proceed within the enzyme active site without shuttling the non-cognate aminoacyl-adenylate intermediate to the remote editing site.
Gruic-Sovulj
Ita
I
Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000 Zagreb, Croatia. gruic@chem.pmf.hr
Rokov-Plavec
Jasmina
J
Weygand-Durasevic
Ivana
I
D000249:Adenosine Monophosphate / Q000737:chemistry*; D001665:Binding Sites; D003545:Cysteine / Q000737:chemistry; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics; D006868:Hydrolysis; D017434:Protein Structure, Tertiary; D017393:RNA Editing; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics; D012694:Serine / Q000031:analogs & derivatives / Q000737:chemistry; D012714:Serine-tRNA Ligase / Q000737:chemistry* / Q000235:genetics; D013379:Substrate Specificity; D013912:Threonine / Q000737:chemistry
D029968:Escherichia coli Proteins; D029701:Saccharomyces cerevisiae Proteins; D013912:Threonine; C028002:serine hydroxamate; D000249:Adenosine Monophosphate; D012694:Serine; D012714:Serine-tRNA Ligase; D003545:Cysteine