Poster abstracts

Poster number 48 submitted by Anne-Cecile Duc

Targeting the A-site rRNA with peptides

Anne-Cecile E. Duc (Department of Chemistry, Wayne State University), Chamila N. Rupasinghe, Adnan Memic, Edvin Klosi, Tony H. Wang (Department of Chemistry, Wayne State University), Mark R. Spaller (Department of Chemistry, Wayne State University), Christine S. Chow (Department of Chemistry, Wayne State University)

Abstract:
The ribosome is a known target for antibiotics, which bind to a limited number of sites, in both the large and the small ribosomal subunits.(1) One important target is the A site of the 16 S rRNA of the 30 S subunit. The universality of the decoding phenomenom renders the A site an interesting target, with reduced possibilities for mutations. In our research, diverse modes of selection were used to identify peptides that bind to the 27-nucleotide A-site RNA model,(2) including phage display and chemical split-pool peptide library synthesis. Biophysical characterization of the selected peptide sequences was done using several methods, such as fluorescence spectroscopy, electrospray-ionization mass spectrometry, and enzymatic footprinting. These studies give some insights about the affinity and specificity of the peptides with their target RNA. Understanding these intreactions will lead us to modify the peptides to enhance their affinity and specificity, therefore their activity.

References:
1. Steitz. T. A., On the structural basis of peptide-bond formation and antibiotic resistance from atomic structures of the large ribosomal subunit. FEBS Letters 2005, 579, 955-958.
2. Fourmy D., Blanchard S. C., Puglisi J. D., Science 274, 1367 (22 november, 1996).

Keywords: rRNA, peptides