Skoulas, D.; Ojo, O.M.; Thalhammer, A.; Kochovski, Z.; Schlaad, H.: Solution Behavior of Glyco-Copoly(l-Glutamic Acid)s in Dilute Saline Solution. Biomacromolecules 25 (2024), p. 3724-3730
10.1021/acs.biomac.4c00288
Open Access Version
Abstract:
A small series of copoly(α,l-glutamic acid/dl-allylglycine)s with the same chain length and allylglycine content (∼10 mol %) but different spatial distribution of allylglycine units was synthesized and subsequently glycosylated via thiol-ene chemistry. Dilute aqueous copolypeptide solutions (0.1 wt %, physiological saline) were analyzed by circular dichroism spectroscopy, dynamic light scattering, and cryogenic transmission electron microscopy. The copolypeptides adopted a random coil or α-helix conformation, depending on solution pH, and the glycosylated residues either distorted or enhanced the folding into an α-helix depending on their location and spatial distribution along the chain. However, regardless of their secondary structure and degree of charging, all partially glycosylated copolypeptides self-assembled into 3D spherical structures, supposedly driven by a hydrophilic effect promoting microphase separation into glucose-rich and glutamate-rich domains.