Turn residues in beta-hairpin peptides as points for covalent modification

ORGN 430

W. John Cooper, jcooper4@email.unc.edu and Marcey L. Waters, mlwaters@email.unc.edu. Department of Chemistry, University of North Carolina at Chapel Hill, CB 3290, Venable Hall, Chapel HIll, NC 27599
Beta-turns are known to be important sites for protein-protein and protein-peptide interactions, but there has been little research exploring the range of functionality that can be incorporated while maintaining a well-folded structure. To probe the effect of amending turn residue side chains, beta-hairpin peptides containing the known type 1' turn sequence Val-Asn-Gly-Orn(Lys) were synthesized with modifications that include alkylation of Asn and acylation of Lys. Analysis by NMR demonstrates that in moderately to well-folded systems these variations impose only a small energetic penalty (<0.5 kcal/mol). These results illustrate the potential that beta-turns possess for covalent modification allowing the display of a wide range of functionality. Specific applications including biotinylation and fluorescent labeling will be discussed.

Bioorganic, Metal-Mediated Reactions, and Molecular Recognition
8:00 PM-10:00 PM, Tuesday, 30 August 2005 Washington DC Convention Center -- Hall A, Poster

8:00 PM-10:00 PM, Monday, 29 August 2005 Washington DC Convention Center -- Hall A, Sci-Mix

Division of Organic Chemistry

The 230th ACS National Meeting, in Washington, DC, Aug 28-Sept 1, 2005