Nanoribbon self-assembly and hydrogel formation from an NOctanoyl octapeptide derived from the antiparallel β-Interface of a protein homotetramer

The effect of installing different lipid chains (C₆, C₈, C₁₀, and C₁₆) on the N-terminus of an octapeptide derived from the antiparallel β-interface of the diaminopimelate decarboxylase protein homotetramer has been investigated. Notably, the C₈ peptide conjugate assembled into wide twisted nanoribbons and formed hydrogels, which to the best of our knowledge constitutes the first example of a peptide containing an eight carbon alkyl chain that demonstrates these properties, a space typically occupied by peptide amphiphiles with long lipid chains. Furthermore, this self-assembling lipopeptide exhibited pH and temperature stability with shear thinning properties suitable for biomedical applications. Importantly, in this work the application of the polystyrene-based sorbent Diaion™ HP20SS for the simple large-scale purification of self-assembling peptides is presented as an alternative to the use of time-consuming and labor-intensive reverse-phase high-performance liquid chromatography. STATEMENT OF SIGNIFICANCE: Peptides that can self-assemble into defined nanostructures are highly attractive for many biomedical applications given their unique physical and chemical properties. It is recognized that self-assembling peptides derived from naturally occurring proteins offer an unlimited source of functionalities and structures, which are hard to uncover with designed sequences. In this study, we have investigated the effect of installing different lipids chains on the N-terminus of an octapeptide derived from the antiparallel β-interface of the diaminopimelate decarboxylase protein homo tetramer. We also reported the use of polymeric Diaion^Ⓡ HP20SS beads as an alternative solid support to purify self-assembling peptides.