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Controlling self-assembly of diphenylalanine peptides at high pH using heterocyclic capping groups.

ABSTRACT: Using small angle neutron scattering (SANS), it is shown that the existence of pre-assembled structures at high pH for a capped diphenylalanine hydrogel is controlled by the selection of N-terminal heterocyclic capping group, namely indole or carbazole. At high pH, changing from a somewhat hydrophilic indole capping group to a more hydrophobic carbazole capping group results in a shift from a high proportion of monomers to self-assembled fibers or wormlike micelles. The presence of these different self-assembled structures at high pH is confirmed through NMR and circular dichroism spectroscopy, scanning probe microscopy and cryogenic transmission electron microscopy.

SUBMITTER: Martin AD

PROVIDER: S-EPMC5341053 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Controlling self-assembly of diphenylalanine peptides at high pH using heterocyclic capping groups.

Martin Adam D AD Wojciechowski Jonathan P JP Robinson Andrew B AB Heu Celine C Garvey Christopher J CJ Ratcliffe Julian J Waddington Lynne J LJ Gardiner James J Thordarson Pall P

Scientific reports 20170308

Using small angle neutron scattering (SANS), it is shown that the existence of pre-assembled structures at high pH for a capped diphenylalanine hydrogel is controlled by the selection of N-terminal heterocyclic capping group, namely indole or carbazole. At high pH, changing from a somewhat hydrophilic indole capping group to a more hydrophobic carbazole capping group results in a shift from a high proportion of monomers to self-assembled fibers or wormlike micelles. The presence of these differe ...[more]

PMID: 28272523

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