Peptide diacetylenes

Fig. 27 Peptide-diacetylene P-sheet (formed by self-assembly of 2) before (p2) and after (P2) polymerisation. Reproduced with permission from Jahnke et al. [70], Copyright Wiley-VCH...

Furthermore, Oda et al. pointed out that there are two topologically distinct types of chiral bilayers, as shown in Figure 5.46.165 Helical ribbons (helix A) have cylindrical curvature with an inner face and an outer face and are the precursors of tubules. These are, for example, the same structures that are observed in the diacetylenic lipid systems discussed in Section 4.1. By contrast, twisted ribbons (helix B) have Gaussian saddlelike curvature, with two equally curved faces and a C2 symmetry axis. They are similar to the aldonamide and peptide ribbons discussed in Sections 2 and 3, respectively. The twisted ribbons in the tartrate-gemini surfactant system were found to be stable in water for alkyl chains with 14-16 carbons. Only micelles form... 

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.

Frauenrath, H., Jahnke, E., Weiss, J. et al. (2009) Synthesis of diacetylene-containing peptide building blocks and amphiphiles, their self-assembly and topochemical polymerization in organic solvents. Chemistry - A European Journal, 15,388 04. 

Mehla, J. and Sood, S.K. (2011). Substantiation in Enterococcus faecalis of dose-dependent resistance and crossresistance to pore-forming antimicrobial peptides by use of a poly diacetylene-based color metric assay. Appl Environ Microbiol 77, 786-793. 

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