title: Cross-Linking and Bundling of Self-Assembled Protein-Based Polymer Fibrils via Heterodimeric Coiled Coils.
abstract: Previously, we developed triblock protein polymers that form fibrillar hydrogels at low protein polymer concentrations (denoted C2-SH48-C2). We here demonstrate that the structure of these hydrogels can be tuned via heterodimeric coiled coils that cross-link and bundle the self-assembled protein polymer fibrils. We fused well-characterized, 47 amino acids-long heterodimeric coiled coil "linkers" (DAor DB) to the C-terminus of the triblock polymer. The resulting C2-SH48-C2-DAand C2-SH48-C2-DBpolymers, were successfully produced as secreted proteins in Pichia pastoris, with titers of purified protein in the order of g L-1of clarified broth. Atomic force microscopy showed that fibrils formed by either C2-SH48-C2-DAor C2-SH48-C2-DBalone already displayed extensive bundling, apparently as a result of homotypic (DA/DAand DB/DB) interactions. For fibrils prepared from protein polymers having no linkers, plus a small fraction of polymers containing either DAor DBlinkers, no cross-linking and bundling was observed. At these same low concentrations of linkers, fibrils containing both the DAand the DBlinkers did show cross-linking and bundling as a consequence of heterodimer formation. This work shows that we can control the extent of bundling and cross-linking of supramolecular fibrils by varying the density of heterodimerizing coiled coils in the fibrils, which is promising for the further development of materials that mimic the extracellular matrix.
authors: Wageningen UR Food and Biobased Research, 6708 WG Wageningen, The Netherlands.|Physical Chemistry and Soft Matter, Wageningen University Stippeneng 4, 6708 WE Wageningen, The Netherlands.
authors: Natalia E
authors: NE
authors: Domeradzka
authors: Wageningen UR Food and Biobased Research, 6708 WG Wageningen, The Netherlands.
authors: Marc W T
authors: MW
authors: Werten
authors: Wageningen UR Food and Biobased Research, 6708 WG Wageningen, The Netherlands.
authors: Frits A
authors: FA
authors: de Wolf
authors: Physical Chemistry and Soft Matter, Wageningen University Stippeneng 4, 6708 WE Wageningen, The Netherlands.
authors: Renko
authors: R
authors: de Vries
mesh_terms: D003432:Cross-Linking Reagents / Q000737:chemistry*; D020100:Hydrogels / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism; D010843:Pichia / Q000254:growth & development / Q000378:metabolism*; D011108:Polymers / Q000737:chemistry* / Q000378:metabolism; D015202:Protein Engineering; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D003432:Cross-Linking Reagents; D020100:Hydrogels; D010446:Peptide Fragments; D011108:Polymers; D011506:Proteins; D011994:Recombinant Proteins