Peptide assemblies

Many examples exist of using this protein motif to construct hydrogels from protein or peptide assembly. For example, Dong et al., reported elongated fibrils with diameters as small as 4 nm by incorporation of charged amino acids in the... 

Amorin, M., Castedo, L., and Granja, J. R. (2003). New cyclic peptide assemblies with hydrophobic cavities The structural and thermodynamic basis of a new class of peptide nanotubues./. Am. Chem. Soc. 125, 2844-2845. 

E Atherton, PM Hardy, DE Harris, H Matthews. Racemization of C-terminal cysteine during peptide assembly, in E Giralt, D Andreu, eds. Peptides 1990. Proceedings of the 21st European Peptide Symposium. Escom, Leiden, 1991, pp 243-244. 

Pike, C.J., Burdick, D., Walencewicz, A.J., Glabe, C.G., and Cotman, C.W., Neurodegeneration induced by beta-amyloid peptides in vitro the role of peptide assembly state,. Neurosci., 13, 1676,1993. 

Similarly, iterative NRPSs operate in a linear fashion but utilize at least one domain or module multiple times for the synthesis of a single NRP product. Thus, peptides assembled by iterative synthetases contain short, repeating units of peptide building blocks. In such systems, the terminal PCP-TE (or infrequendy PCP-C) didomain is responsible for both condensation of the repeating peptide units and chain release from the assembly line. NRPs biosynthesized in this manner include enniatin, enterobactin, bacillibactin, " gramicidin and the depsi-peptides valinomycin and cereulide. Of these examples, condensation of the precursor peptides for both enterobactin and gramicidin S has been extensively studied and will be discussed in detail. 

Schnarr, N. A. Kennan, A. J. Specific control of peptide assembly with combined hydrophilic and hydrophobic interfaces. J. Am. Chem. Soc. 2003,125, 667-671. 

Rajangam K, Behanna HA, Hui MJ, Han X, Hulvat JF, Lomasney JW, Stupp SI. Heparin binding nanostructures to promote growth of blood vessels. Nano Lett 2006 6 2086-2090. Rapaport H. Ordered peptide assemblies at interfaces. Supramol Chem 2006 18 445-454. Rapaport H, Moeller G, Knobler CM, Jensen TR, Kjaer K, l eiserowitz L, Tirrell DA. Assembly of triple-stranded /3-sheet peptides at interfaces. J Am Chem Soc 2002 124 9342-9343. 

Two independent screens have been developed to investigate the effects of fluorinated building blocks on the interactions of the dimeric peptide assembly. The impact of fluorine side chain substitutions on the stability of coiled coil folding has been studied using temperature-dependant CD spectroscopy. The second screen is based on the ability of a-helical peptides to self-replicate. Thus, peptide... 

Peptide assembly commenced with Boc-Glu(OBzl)-NHMe, Boc-Glu(OBzl)-OH, Boc-Ser-[PO(OPh)2]-OH, Boc-Leu-OH, and AcOH being coupled as their isobutoxycarbonyl mixed anhydrides [repetitive excess mixed anhydride (REMA) method] and the Boc group cleaved by 40% TFA/CH2C12 (30 min). 

Nitrophenylalanine was originally used as a non-photolabile precursor for the photo-reactive 4-azidophenylalanine,121 to be converted into the light-labile compound at the completion of peptide assembly. In 1975, Escher and Schwyzer reported that it also acts as a photophore 16 Its advantages as a photophore are due to its stability under ambient light conditions and in the presence of liquid HF, which are conditions used in many solid-phase peptide syntheses. 

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