Peptide-polymer hybrids

Mei Y, Beers KL, Byrd HCM et al (2004) Solid-phase atrp synthesis of peptide- polymer hybrids. J Am Chem Soc 126 3472-3476... 

Fig. 11 Totally solid phase approach to the synthesis of a peptide-polymer hybrid material [52]...

In a second article the same approach was used to synthesize a peptidic polymer containing the peptide Tritrpticin, a 13 residue antimicrobial peptide (Fig. 16) [66]. This time they initiated the polymerization of f-butyl acrylate, followed by styrene to produce a triblock copolymer, which clearly formed micelles in solution. Interestingly, the antimicrobial activity of the peptide was enhanced relative to the free peptide and the detrimental side effects normally associated with antimicrobial peptides, such as a high hemolytic activity, were reduced, highhghting the benefits of using peptide polymer hybrids in place of peptides alone. 

In a third example of this methodology Mei et al. [65] produced a polymer containing the fibronectin-based peptide sequence GRGDS, a well-known cell adhesion sequence. This time, however, the polymerization of hydroxyethyl methacrylate was carried out on the sohd support in methyl ethyl ke-tone/propanol (7 3), resulting in a bio-hybrid with a polydispersity of 1.5. This peptide-polymer hybrid material was used as a support for the growth of mouse NIH-3T3 fibroblasts. It was shown that the cells adhered better to the polymer containing the peptide than to the unfunctionalized control polymer. This highhghts one of the many potential applications for protein-polymer hybrid materials. 

There are several examples in which protein engineering has been used to introduce specific functionalities at different points in a protein via site-directed mutagenesis, to facilitate the synthesis of peptide polymer hybrid materials. Stayton et al. [91] used protein engineering to create an N49C mutant streptavidin, in which the asparagine at position 49 was substituted... 

Mei, Y., et al. 2004. Solid-phase ATRP synthesis of peptide— polymer hybrids. Journal of the American Chemical Society 126(11) 3472-3476. 

Couet J, Jeyaprakash JD, Samuel S, Kopyshev A, Santer S et al (2005) Peptide-polymer hybrid nanotubes. Angew Chem Int Ed 44 3297-3301... 

Fig. 14 Chemical structures of various peptide-polymer hybrids that self-assemble into )6-sheet-based fibrous nanostructures...

Another approach for fabricating the peptide-polymer hybrid nanofibers is the polymerization method at the surface of self-assembled /3-sheet nanofibers (or nanotubes). In the jd-sheet structure, adjacent /3-strands align... 

Atom transfer radical polymerization (ATRP) is also an interesting strategy to construct peptide-polymer hybrid ID-arrays. Graft-polymerization of AT-isopropylacrylamide was carried out from the surface of self-assembled peptide nanotube in water, and as a result, cyclicpeptide-poly(f -isopropyl-acrylamide) hybrid nanotube was successfully prepared (Fig. 19) [61]. fii other words, this research indicates that surface chemistry of ID-peptide nano-assembly can be adjusted by the grafted synthetic polymers, such as thermo-sensitive PNIPAM and polyelectrolytes. 

Fig. 19 Schematic outline of the synthesis of peptide-polymer hybrid nanostructure. A cyclicpeptide with ATRP initiators self-assembles to form a peptide nanotube through /S-sheet formation. A subsequent surface-initiated ATRP of NIPAM monomer coats the peptide nanotube by PNIPAM-shell. (Adapted from [61])...

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