title: Peptide Backbone Composition and Protease Susceptibility: Impact of Modification Type, Position, and Tandem Substitution.
abstract: The clinical utility of peptides is limited by their rapid degradation by endogenous proteases. Modification of the peptide backbone can generate functional analogues with enhanced proteolytic stability. Existing principles for the design of such oligomers have focused primarily on effective structural mimicry. A more robust strategy would incorporate a rational approach for engineering maximal proteolytic stability with minimal unnatural residue content. We report here the systematic comparison of the proteolytic resistance imparted by four backbone modifications commonly employed in the design of protease-stable analogues of peptides with complex folding patterns. The degree of protection was quantified as a function of modification type, position, and tandem substitution in the context of a long, unstructured host sequence and a canonical serine protease. These results promise to inform ongoing work to develop biostable mimics of increasingly complex peptides and proteins.
authors.affiliation: Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, PA, 15213, USA.
authors.forename: Halina M
authors.initials: HM
authors.lastname: Werner
authors.affiliation: Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, PA, 15213, USA.
authors.forename: Chino C
authors.initials: CC
authors.lastname: Cabalteja
authors.affiliation: Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, PA, 15213, USA. horne@pitt.edu.
authors.forename: W Seth
authors.initials: WS
authors.lastname: Horne
mesh_terms: D008958:Models, Molecular; D010447:Peptide Hydrolases / Q000737:chemistry / Q000378:metabolism*; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D059748:Proteolysis
chemical_list: D010455:Peptides; D010447:Peptide Hydrolases
keywords: foldamers; peptides; peptidomimetics; proteases; protein-protein interactions