Biantennary oligoglycines and glyco-oligoglycines self-associating in aqueous medium

Abstract

SummaryOligoglycines designed in a star-like fashion, so-called tri- and tetraantennary molecules, were found to form highly ordered supramers in aqueous medium. The formation of these supramers occurred either spontaneously or due to the assistance of a mica surface. The driving force of the supramer formation is hydrogen bonding, the polypeptide chain conformation is related to the folding of helical polyglycine II (PG II). Tri- and tetraantennary molecules are capable of association if the antenna length reach 7 glycine (Gly) residues. Properties of similar biantennary molecules have not been investigated yet, and we compared their self-aggregating potency with similar tri- and tetraantennary analogs. Here, we synthesized oligoglycines of the general formula R-Glyn-Х-Glyn-R (X = -HN-(СН2)m-NH-, m = 2, 4, 10; n = 1–7) without pendant ligands (R = H) and with two pendant sialoligands (R = sialic acid or sialooligosaccharide). Biantennary oligoglycines formed PG II aggregates, their properties, however, differ from those of the corresponding tri- and tetraantennary oligoglycines. In particular, the tendency to aggregate starts from Gly4 motifs instead of Gly7. The antiviral activity of end-glycosylated peptides was studied, and all capable of assembling glycopeptides demonstrated an antiviral potency which was up to 50 times higher than the activity of peptide-free glycans.

Smart Complex Fluids Based on Two‐Antennary Oligoglycines

“…The adsorption from these solutions again leads to a partial decrease of hydrophilicity of the substrates. One possible reason might be the formation of oligoglycine monolayer coverage on the substrate with the hydrophilic portions of the molecules directed towards the solution bulk . Patches of a second layer with the opposite orientation of the peptide entities may be formed with the hydrophilic portion of the molecules pointing towards the solution bulk, which results in partial recovery of the hydrophilicity of the substrates.…”

A rare polyglycine type II‐like helix motif in naturally occurring proteins

“…Hexagonal PG II ‐helical structures were originally found in synthetic polyglycines, but subsequently also in various structurally related molecules such as aliphatic polyamides, the tripeptide Pro‐Gly‐Gly, the copolyamide poly(glycyl‐β‐alanine), oligoglycine‐based bolaamphiphiles and antennary oligoglycines . Synthetic polyglycine‐derived supramolecules extend further into two or three dimensions without forming a hydrophobic core.…”

Multifunctional, biocompatible and pH-responsive carbon nanotube- and graphene oxide/tectomer hybrid composites and coatings

“…In the case of oligoglycine solutions, pH values depend on concentration, due to HCl coming from oligoglycine synthesis. 49,55 Thus, for 2 mg mL -1 , 1 mg mL -1 and 0.5 mg mL -1 2T solutions in water, pH was 5.2, 5.6, and 5.8, respectively, while in the case of 4T, pH was 5.7, 6.0, and 6.1. Buffer pH 12.0 was purchased from Aldrich, while buffer pH 7.4 and buffer pH 2.2 were prepared from Na 2 HPO 4 and NaH 2 PO 4 solutions, and from citric acid and Na 2 HPO 4 solutions, respectively.…”

“…Amino-terminated bi-, tri-, and tetraantennary oligoglycines non-covalently assemble, through cooperative hydrogen bonding formation, into biocompatible rigid, two-dimensional (2D) structures called tectomers, either in solution or in surface-promoted processes. 48,49 The unique self-assembly features of amino-terminated oligoglycine have been successfully exploited to coat negatively-charged surfaces, such as mica 48,50 and bacteria membranes, 51 viruses through oligoglycine glycosylation, 50,52,53 and polymer fibers by covalent functionalization. 54 Furthermore, we have recently demonstrated the capabilities of tectomers as efficient pH-sensitive nanocarriers, making them extremely attractive for biosensing and therapeutic applications.…”