Peptide-polymer conjugation

Borner and coworkers demonstrated that peptide-polymer conjugates can assemble to nanotapes with persistence lengths close to those of actin filaments (actin composes one part of the intercellular skeleton) [108, 109]. The generated nanostructures are flat ribbons (1.2 nm x 17 nm x 2 pm height x width x length) with... 

In this chapter, some methods for peptide-polymer conjugate synthesis are described and a number of examples are reviewed to illustrate the use of self-assembling peptide sequences to drive nanoscale organization. Conjugation of polymers with proteins or peptides for reasons other than self-assembly, for example, therapeutic protein or peptide PEGylation to prolong in vivo circulation half-lives, are not covered. 

Potential applications of peptide-polymer conjugates include drug delivery materials, optoelectronics, biosensors, tissue scaffolds, tissue replacement materials, hydrogels, adhesives, biomimetic polymers, lithographic masks, and templates for metallic or silica nanostructures. 

Hentschel, J., ten Cate, M.G.J., and Borner, H.G. "Peptide-guided organization of peptide-polymer conjugates expanding the approach from oligo- to polymers". Macromolecules 40(26), 9224-9232 (2007). 

Loschonsky, S., Couet, J., and Biesalki, M. "Synthesis of peptide/polymer conjugates by solution ATRP of butylacrylate using an initiator-modified cyclic D-alt-L-peptide". Macromol. 

Another encapsulation method, which has been used for short peptides, involves linking them to a larger polymer by reversible disulflde linkages [37, 58], The peptide/polymer conjugate can be either immobilized on the capsule wall or free... 

Figure 12 Peptide-polymer conjugates as tools to transfer the four basic concepts of proteins into the world of polymer science, (a) Precisely defined interactions along the polymer chain, (b) Programmable formation of hierarchical structures, (c) Positioning of functionalities to generate functions, (d) Active interactions with biological systems.

Figure 22 Schematic illustration of the peptide-guided organization of peptide-polymer conjugates by the self-assembly of peptide-aggregator domains. Peptide structure motifs such as p-sheet and a-helical coiled-coil (left) and peptide-guided organization of bioconjugates (right) forming fibrillar structures by the p-sheet secondary structure and distinct nano-objects by the coiled-coil motif (bottom).

Figure 29 Schematic illustration of the approach combining (1) peptide-directed self-assembly of polymer-peptide conjugates and (2) polymerization of positioned diacetylene moieties. Peptide-polymer conjugates (top, a) first organize into supramolecular assemblies (top, b), which exhibit a distinct superhelical structure (bottom) this can be converted into conjugated polymers (red) under retention of their previously assembled structure (top, c). Reprinted with permission from Frauenrath, H. Jahnke, E. Chem. Eur. J. 2008, 14, 2942. Copyright 2007, Wiley-VCH.

The p-sheet formation tendency of a peptide-polymer conjugate could be strongly enhanced by utilizing a suitable organic template to preorganize peptide segments in the... 

Figure 32 Hierarchically structured composite fibers formed by a hybrid process, combining self-assembly of polymer-peptide nanotapes with peptide-directed silicification. ( Organic hierarchy levels are classified as peptide-polymer conjugate (level I), nanotapes with single p-sheet core (level II) and double p-sheet core (level III). Composite hierarchy levels are specified as proto-composite tapes (level IV), proto-composite fibers (level V), and fiber bundles (level VI).) Adapted from Kessel, S. Thomas, A. Borner, H. G. Angew. Chem., Int. Ed. 2007, 46, 9023 and Kessel, S. Bomer, H. G. Macromol. Rapid Commun. 2008,29,419. Reprinted with permission from Bomer, H. G. Prog. Polym. Sci. 2009,34,811. Copyright 2009, Elsevier. ...

Beyond these three main concepts, the inverse bioconjugation approach offers another strategy to connect peptides or proteins with synthetic polymers. Using a solid support, which is preloaded with a polymer block, the biological molecule can be assembled in a stepwise fashion through solid-phase synthesis. Mutter and coworkers first showed the attachment of PEO to a poly(styrene) resin via a benzyl ether linker. This concept was finally developed further by Bayer and Rapp leading to a commercially available PAP resin, which is widely applied in solid-phase peptide synthesis. In a similar approach. Lutz, Borner, and coworkers demonstrated the preparation of cleavable and non-cleavable soluble polystyrene supports by ATRP for the liquid-phase synthesis of peptide-polymer conjugates. ... 

Jia and coworkers took advantage of CuAAC to design an elastin-like peptide-polymer conjugate. The reaction between a bifunctional, azide-terminated PEO block and an alkyne-functionalized peptide composed of two different functional domains yielded a multiblock copolymer (Figure 1.12). 

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