Tripartite functional assembly of a large class I aminoacyl tRNA synthetase

Hydrolytic editing by a class II aminoacyl-tRNA synthetase.

Editing reactions catalyzed by aminoacyl-tRNA synthetases are critical for accurate translation of the genetic code. To date, this activity, whereby misactivated amino acids are hydrolyzed either before or after transfer to noncognate tRNAs, has been characterized extensively only in the case of class I synthetases. Class II synthetases have an active-site architecture that is completely distin...

Aminoacyl-tRNA synthetase-induced cleavage of tRNA.

Aminoacyl-tRNA synthetases interact with their cognate tRNAs in a highly specific fashion. We have examined the phenomenon that upon complex formation E. coli glutaminyl-tRNA synthetase destabilizes tRNA(Gln) causing chain scissions in the presence of Mg2+ ions. The phosphodiester bond cleavage produces 3'-phosphate and 5'-hydroxyl ends. This kind of experiment is useful for detecting conformat...

Six Rossmannoid folds, including the Class I aminoacyl-tRNA synthetases, share a partial core with the anti-codon-binding domain of a Class II aminoacyl-tRNA synthetase

MOTIVATION Similarities in core residue packing provide evidence for divergence or convergence not reported using other methods. RESULTS We apply a new method for rapid structure comparison based on Simplicial Neighborhood Analysis of Protein Packing (SNAPP) to the diverse structural classification of proteins (SCOP) alpha/beta-class of protein folds. The procedure identifies inter-residue pa...

A truncated aminoacyl-tRNA synthetase modifies RNA.

Aminoacyl-tRNA synthetases are modular enzymes composed of a central active site domain to which additional functional domains were appended in the course of evolution. Analysis of bacterial genome sequences revealed the presence of many shorter aminoacyl-tRNA synthetase paralogs. Here we report the characterization of a well conserved glutamyl-tRNA synthetase (GluRS) paralog (YadB in Escherich...

Title Crystal Structure of Asparagine Synthetase Reveals a Close Evolutionary Relationship to Class II Aminoacyl-tRNA Synthetase (MOLECULAR BIOFUNCTION-Functional