In recent years, our laboratory has developed the thioamide, a single O to S substitution in canonical amide bonds, as a versatile probe for fluorescence and protease studies. Thus far, thioamides have been incorporated into the backbone of proteins via native chemical ligation (NCL) with a Cys or homocysteine (Hcs) at the ligation site. We utilized two different strategies to facilitate the site-specific incorporation of thioamides into proteins. First, we investigated selective thiol-desulfurization in the presence of thioamides. This allows us to perform traceless ligation reactions in the presence of thioamides and avoids have a Cys ligation scar. In another approach, showed that using alternative deprotection reagents in solid phase peptide synthesis, reduced epimerization and improved yield of thioamide containing peptides. With these strategies in hand, we synthesized different thioamide containing proteins and assessed their effect on protein stability using Circular Dichroism and thermal denaturation.

Thioamides: Improved incorporation methods and effects on protein stability

254th National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.