Formation of supramolecular structures of a native‐like protein in the presence of amphiphilic peptides: Variations in aggregate morphology

Abstract

a b s t r a c tA striking potential of the amphiphilic dipeptides, Arg-Phe or Asp-Phe, to induce aggregation of a model protein, alcohol dehydrogenase in its native-like state, has been demonstrated under physiologically relevant conditions, using dynamic light scattering, fluorescence spectroscopy, circular dichroism, transmission electron-and atomic force microscopy. The peptide action resulted in accumulation of a variety of morphologically distinct supramolecular structures profoundly differing from those generated by the heat-induced aggregation at the early stages of the process, when amyloid fibril assemblies were not detectable. The biogenic amphiphilic agents are suggested to act as regulators of structural transformations of native-like proteins.

The αA66–80 Peptide Interacts with Soluble α-Crystallin and Induces Its Aggregation and Precipitation: A Contribution to Age-Related Cataract Formation

“…41–44 Our data provide the evidence in support of this phenomenon. First, the quenching of tryptophan fluorescence of α-crystallin by the peptide suggests that the microenvironment of intrinsic tryptophan residues in α-crystallin is altered as a consequence of peptide binding.…”

“…Rapid aggregation of soluble proteins can be caused by self-association of proteins (which might be accompanied by subtle conformational changes), leading to the formation of small oligomers or HMW soluble or insoluble aggregates − as a result of interactions with peptides and small molecules. − Our data provide the evidence that supports this phenomenon. First, the quenching of the tryptophan fluorescence of α-crystallin by the peptide suggests that the microenvironment of intrinsic tryptophan residues in α-crystallin is altered as a consequence of peptide binding.…”

Functionalization of hydrophobic surfaces with antimicrobial peptides immobilized on a bio-interfactant layer

“…Laccase and peptides could interact not only by π–π stacking but also, by electrostatic interactions between the charged functional groups and formed hydrogen bonds. 34 ITC titration curves of the Tet 124-G-BrPh-DOPA-G into laccase/maltodextrin suspension shows a characteristic curve for an enzymatic reaction on contrary to Tet-124-G-BrPh (Fig. S1 † ).…”

Dynamic Covalent Disulfide Exchange Mediates Oral Delivery of Biomacromolecules

“…Complex coacervation of insulin with in-situ growing poly(disul de)s Given that dithiolanes tend to undergo concentration-dependent, strain-release-promoted ring-opening polymerization 20,21 , we surmise that, when the negatively charged patches on insulin surface bind the positively charged heads of amphiphilic LGs via salt bridges, the resulting decrease in net surface charge together with an increase in hydrophobicity will induce preliminary phase separation 27 , whereby the locally concentrated dithiolanes spontaneously grow into poly(disul de)s. The latter concomitantly form multivalent interaction-stabilized complex coacervates with insulin (Fig. 1a, b, Supplementary Fig.…”