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

Abstract

Oligoglycines 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 selfaggregating potency with similar tri-and tetraantennary analogs. Here, we synthesized oligoglycines of the general formula R-Gly n-?-Glyn-R (X =-HN-(2)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 Gly 7. 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. ©2014 Tsygankova et al;.