Loading...
Please wait, while we are loading the content...
Similar Documents
Self-assembling homopolymeric peptide tapes in moderately polar organic solvents
| Content Provider | Semantic Scholar |
|---|---|
| Author | Aggeli, Amalia Bell, Mark Owens, Robert W. Smith, Amy Boden, Neville |
| Copyright Year | 1999 |
| Abstract | K 2 4 ( N H2 -KLEALYVLGFFGFFTLGIMLSYIR-COOH), modelled on the single transmembrane domain of IsK protein, was synthesised using standard automated solid phase synthesis protocols [3]. In very dilute solutions in methanol (below 5 μM), the peptide exists in a predominantly monomeric random coil state, as revealed by Circular Dichroism (CD) spectroscopy. Above a critical peptide concentration, ca 5 μM, the peptide molecules self-assemble into β -sheets, as observed by a characteristic minimum ellipticity at 216 nm in the CD spectra [2]. Clear, thermostable, self-supporting gels are obtained for peptide concentations in excess of 0.2% v/v (mM concentation). The polymeric structures giving rise to the gel network can be directly visualised by atomic force microscopy (AFM) and transmission electron microscopy (TEM). A typical AFM image of a K24 β -sheet polymer from a methanolic peptide gel is shown in Figure 1. The polymer is seen to be several micrometers in length, and to twist around itself to produce a distinctive loop. The thickness of the polymer (z axis, perpendicular to the plane of the image) was measured to be 0.5–1 nm, corresponding to the thickness of a single β sheet. The width of the polymer, ca 8 nm, was found to be in agreement with the expected length of a 24-residue peptide in a fully extended β -strand conformation. These observations show that the peptide β -strands self-assemble in register, with their long axes perpendicular to the long axis of the tapes (cross β structure). Specific peptide–peptide interactions are believed to drive the alignment of the peptide molecules during self-assembly. This is necessary in order to produce one-dimensional self-assembling elongated polymers, as opposed to |
| Starting Page | 73 |
| Ending Page | 75 |
| Page Count | 3 |
| File Format | PDF HTM / HTML |
| DOI | 10.1007/0-306-46864-6_21 |
| Alternate Webpage(s) | https://page-one.springer.com/pdf/preview/10.1007/0-306-46864-6_21 |
| Alternate Webpage(s) | https://doi.org/10.1007/0-306-46864-6_21 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
