Low Fouling Peptides with an All (<scp>d</scp>) Amino Acid Sequence Provide Enhanced Stability against Proteolytic Degradation While Maintaining Low Antifouling Properties
Cindy D. Beyer, Matthew L. Reback, Natalie Heinen, Sugina Thavalingam, Axel Rosenhahn, Nils Metzler‐Nolte
Abstract
Peptide-functionalized surfaces, composed of optimized l -peptides, show a high resistance toward nonspecific adsorption of proteins. As l -peptides are known to be prone to proteolytic degradation, the aim of this work is to enhance the stability against enzymatic degradation by using the all d -peptide mirror image of the optimized l -peptides and to determine if the all d -enantiomer retains the protein-resistant and antifouling properties. Two l -peptides and their d -peptide mirror images, some of them containing the nonproteinogenic amino acid α-aminoisobutyric acid (Aib), were synthesized and tested against non-specific adsorption of the proteins lysozyme and fibrinogen and the settlement of marine diatom Navicula perminuta and marine bacteria Cobetia marina . Both the d -enantiomer and the insertion of Aib protected the peptides from proteolytic degradation. Protein resistance was enhanced with the d -enantiomers while maintaining the resistance toward diatoms.