Thursday, 08. August 2019, 14.15 p.m. 

Ernst-Abbe-Platz 2, Seminarraum 3423

Characterization of Amino Acid Recognition in Aminoacyl-tRNA Synthetases

Dr. Florian Kaiser
(Center for Molecular and Cellular Bioengineering (CMCB), TU Dresden)

Genetic code and translation are key to all life. As a consequence, all kingdoms and species share the enzymes known as aminoacyl-tRNA synthetases, which link amino acids to their codons. For life to flourish, it is vital that these enzymes correctly implement the genetic code and hence correctly recognize amino acids. There are many theories on the emergence of aminoacyl-tRNA synthetases and their amino acid binding sites. While many insights have been gained from sequence analysis, the accurate amino acid recognition remains elusive. Here we use a novel approach to analyze all currently available aminoacyl-tRNA synthetase structures, which cover the recognition of all proteinogenic amino acids across all kingdoms of life. For the first time, we extensively characterize and quantify the interactions between aminoacyl-tRNA synthetases and bound amino acids. Our results show how different interaction features are used to delineate between the two major enzyme classes and the individual amino acids. Furthermore, we show that these features are conserved across a wide variety of species. The quantification of the similarity between the recognition of individual amino acids allows to pinpoint where the genetic code is vulnerable to encoding errors and additional correction mechanisms had to evolve.