Poster abstracts

Poster number 45 submitted by Adil Moghal

Escherichia coli phenylalanyl-tRNA synthetase post-transfer editing prevents cytotoxic mistranslation of the genetic code with meta-tyrosine formed in oxidative stress conditions.

Adil B. Moghal (The Ohio State Biochemistry Program, The Ohio State University), Tammy J. Bullwinkle, Medha Raina, Andrei Rajkovic, Eleftheria Matsa (The Ohio State University), Noah M. Reynolds (The Ohio State University), Huseyin Kayadibi, Farbod Fazlollahi, Christopher Ryan, Nathaniel Howitz (University of California at Los Angeles), Beth Lazazzera, Kym F. Faull (University of California at Los Angeles)

Abstract:
Aminoacyl-tRNA synthetases are the enzymes responsible for attaching tRNA species with their appropriate amino acids to form aminoacyl-tRNAs, the substrates for ribosomal translation. Escherichia coli (E. coli) phenylalanyl-tRNA synthetase (PheRS) bears post-transfer editing activity that deacylates mischarged tRNA^Phe. Under oxidative stress, the nonprotein amino acid meta-Tyrosine (m-Tyr) accumulates due to direct oxidation of phenylalanine. m-Tyr is a direct threat to translational accuracy and cell survival in a PheRS editing mutant, but not in wild-type E. coli. These data, combined with the observation that PheRS editing activity is dispensable in normal growth conditions, suggest conservation of E. coli PheRS editing is due to the ability to protect the cell from cytotoxic mistranslation of the genetic code under oxidative stress conditions.

Keywords: Protein Mistranslation, Oxidative Stress, Aminoacyl-tRNA Synthetase