The Daily Bulletin

Youngha Ryu, associate professor in the Department of Chemistry and Biochemistry at Texas Christian University, will present "Chemical Biology of Bacteria: N-terminal Protein Modification and Riboswitches" at 12:30 p.m. Thursday, October 15, in Classroom Building B119. This seminar series is sponsored by the Faculty-Student Association. An abstract of his talk appears below.

Abstract
In eukaryotes, N-terminal acetylation is one of the most common post-translational modifications of proteins and plays a significant role in the activity of certain proteins. Nevertheless, this particular modification has been reported for only a few endogenous proteins and several recombinant proteins in bacteria. In this seminar, an N-terminal acetyltransferase involved in this rare bacterial N-terminal protein acetylation and its substrate specificity are presented. Also presented are a few methods for the N-terminal selective chemical modification of proteins.

Mainly found in bacteria, riboswitches are mRNA structures that specifically bind their natural ligand and consequently control the expression of the genes associated with the biosynthesis, transport, or degradation of the specific ligand. Riboswitches have been discovered for many important cellular metabolites including amino acids, nitrogenous bases, and coenzymes. In this seminar, the rational design and synthesis of fluorescent small molecules that probe these natural riboswitches are presented. Our recent efforts in developing synthetic riboswitches that control gene expression in response to exogenous ligands are also presented.