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Ensembles of amino acid side chains often dominate the interfacial interactions of intrinsically disordered proteins; however, backbone contributions are far from negligible. Using a combination of nanoscale force measurements and molecular dynamics simulations, we demonstrated with analogous mussel-mimetic adhesive peptides and peptoids both 34 residues long that highly divergent adhesive/cohesive outcomes can be achieved on mica surfaces by altering backbone chemistry only. The Phe, Tyr, and Dopa containing peptoid variants used in this study deposited as dehydrated and incompressible films that facilitated analysis of peptoid side chain contributions to adhesion and cohesion. For example, whereas Phe and Dopa peptoids exhibited similar cohesion, Dopa peptoids were ∼3 times more adhesive than Phe peptoids on mica. Compared with the peptides, Phe peptoid achieved only ∼20% of Phe containing peptide adhesion, but the Dopa peptoids were >2-fold more adhesive than the Dopa peptides. Cation−π interactions accounted for some but not all of the cohesive interactions. Our results were corroborated by molecular dynamics simulations and highlight the importance of backbone chemistry and the potential of peptoids or peptoid/peptide hybrids as wet adhesives and primers.
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Guidelines for designing peptoid structures: Insights from the Peptoid Data Bank
Abstract The number of structural studies of peptoids has grown dramatically over the past 20 years. To date, over 100 high‐resolution structures have been reported for peptoids, which are typically defined as N‐substituted glycine oligomers. We have collected these structures and standardized their sequence representations to facilitate structural analysis as the dataset continues to grow. These structures are presented online as The Peptoid Data Bank (databank.peptoids.org), which also provides persistent links to the published structural data. This review analyzes the present collection of structures and finds extensive support for grouping side chains by their chemistry at the position adjacent to the backbone nitrogen. Groups of side chains with similar chemistry at this position show similar influences on the conformational preferences of the backbone. We also observe a relationship between the side chain and backbone conformations for many monomers that has not previously attracted significant discussion: the values of the χ1and ϕ dihedrals are correlated. We outline a general design strategy for attaining a specific backbone conformation based on the patterns seen in the collected structures.
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- Award ID(s):
- 2002890
- PAR ID:
- 10415883
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Peptide Science
- Volume:
- 115
- Issue:
- 3
- ISSN:
- 2475-8817
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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