Professor Ian Hamley from the University of Reading, UK, visited our group on 28 November 2014 and gave a seminar.
Lincoln Soft Matter Seminar
Self-Assembling Peptide Conjugates: Nanostructures to Bionanotechnology
Ian W. Hamley (University of Reading, Dept of Chemistry)
28 November, JBL3C0 at 1-2pm
There has been great interest recently in the fibrillization of peptides, including the amyloid beta (Ab) peptide which is involved in diseases such as Alzheimer’s . We have recently commenced a study of the self-assembly of peptides and peptide copolymers based on a fragment KLVFF, corresponding to the core region of Ab(16-20). I will present results on the self-assembly of peptides containing the KLVFF motif along with hydrophobic residues at the N terminus and PEGylated diblock copolymers of these peptides. PEGylation is an important technique in the development of conjugates for applications in therapeutics . Self-assembly is studied in water for hydrophilic peptides and peptide copolymers. Gelation and lyotropic liquid phase formation at higher concentration is also discussed. The effect of PEG molar mass on the self-assembled nanostructure will be discussed . A twisted ribbon fibril structure was observed for a peptide containing non-natural b2-amino acids at the N terminus of KLVFF , and the fascinating structural properties of this will be discussed. However, a PEGylated version of this peptide forms spherical micelles in aqueous solution, pointing to the ability to modulate the self-assembled structure by introduction of amphiphilicity . The conjugate can be enzymatically degraded using a-chymotrypsin, releasing a peptide which does not aggregate. This nanocontainer delivery and release system could be useful in therapeutic applications.
I will also discuss thermoresponsive telechelic PEG/peptides with hydrophobic dipeptide end groups (di-tyrosine or di-phenylalanine), one of which shows a de-gelation transition near body temperature and which may be useful in bioresponsive delivery systems .
Time permitting, recent work on self-assembling lipopeptides will be outlined. Our focus is to investigate potential relationships between self-assembly and bioactivity. We have investigated several designed synthetic (e.g. ) as well as biological and bio-derived lipopeptides (e.g. ) which exhibit remarkable distinct nanostructures as well as diverse bioactivity with applications in cosmeceuticals, antimicrobial materials and immune therapies.
 I. W. Hamley Angew. Chem., Int. Ed. Engl. 2007, 46, 8128; I. W. Hamley, Chem. Rev. 2012, 112, 5147.
 I. W. Hamley Biomacromolecules 2014, 15, 1543.
 V. Castelletto, G. Cheng, I. W. Hamley Soft Matter 2012, 8, 5434.
 V. Castelletto et al. Angew. Chem., Int. Ed. Engl. 2009, 48, 2317; J. Adamcik, V. Castelletto, S. Bolisetty, I. W. Hamley and R. Mezzenga, Angew. Chem., Int. Ed. Eng., 2011, 50, 5495.
 V. Castelletto et al. Langmuir 2010, 26, 11624.
 I. W. Hamley, G. Cheng, V. Castelletto, Macromol. Biosci. 2011, 11, 1068.
 V. Castelletto et al. Chem. Comm. 2010, 46, 9185; R. R. Jones et al. Mol. Pharm. 2013, 10, 1063.
 I. W. Hamley et al. Soft Matter 2013, 9, 9572.