Digital Commons Network^™

Trna Aminoacylation: New Protein Players And New Reactions, Whitney Noel Wood

Wayne State University Dissertations

TRNA AMINOACYLATION: NEW PROTEIN PLAYERS AND NEW REACTIONS

by

WHITNEY N. WOOD

May 2019

Advisor: Dr. Tamara L. Hendrickson

Major: Chemistry (Biochemistry)

Degree: Doctor of Philosophy

Protein translation must usually occur with high accuracy for an organism to survive. However, Helicobacter pylori, Staphylococcus aureus, and many other microorganisms including important human pathogens, lack one or more aminoacyl-tRNA synthetase (aaRS), the enzymes that typically aminoacylate tRNAs for ribosomal translation. These organisms must use an indirect pathway to aminoacylate some tRNAs. Specifically, H. pylori lacks the genes that encode for asparaginyl- and glutaminyl-tRNA synthetases (AsnRS and GlnRS, respectively). Instead, H. pylori uses …

Functional Characterization Of Accessory Proteins And Novel Activities In Direct And Indirect Trna Aminoacylation, Udumbara Menike Rathnayake

Wayne State University Dissertations

Indirect tRNA aminoacylation is essential for most bacteria and archaea, particularly when these species do not have genes encoding asparaginyl- and/or glutaminyl-tRNA synthetase (AsnRS and GlnRS). In the absence of AsnRS, the first step in Asn-tRNAAsn synthesis involves misacylation of tRNAAsn with aspartate to produce Asp-tRNAAsn; this reaction is catalyzed by a non-discriminating aspartyl-tRNA synthetase (ND-AspRS). Subsequently, in bacteria, an amidotransferase called GatCAB converts Asp-tRNAAsn to Asn-tRNAAsn. An analogous, two-step processes exist to produce Gln-tRNAGln. In this case, a non-discriminating glutamyl-tRNA synthetase (ND-GluRS) misacylates tRNAGln to produce Glu-tRNAGln, which is then converted to Gln-tRNAGln by GatCAB. The central hub of …