Complexes and supramolecular associates of dodecyl-containing oligonucleotides with serum albumin

Abstract

Serum albumin is currently in the focus of biomedical research as a promising platform for the creation of multicomponent self-assembling systems due to the presence of several sites with a high binding affinity of various compounds in its molecule, including lipophilic oligonucleotide conjugates. In this work, we investigated the stoichiometry of the dodecyl-containing oligonucleotides binding to bovine and human serum albumins via electrophoretic mobility shift assay. The results testify to the formation of albumin-oligonucleotide complexes with a stoichiometry of about 1 : (1.25 ± 0.25) under physiological-like conditions. Using atomic force microscopy, it was found that interaction of human serum albumin with a duplex of complementary dodecyl-containing oligonucleotides resulted in associates of round shape with a diameter of 165.5 ± 94.3 nm and 28.9 ± 16.9 nm in height, and with polydeoxyadenylic acid and dodecyl-containing oligothymidylate also resulted in formation of supramolecular associates with a size of about 315.4 ± 70.9 and 188.3 ± 43.7 nm. The obtained data allow considering dodecyl-containing oligonucleotides and albumin as potential components for the development of methods to design self-assembled systems for solving problems of molecular biology, biomedicine, and the development of unique theranostics with targeted action.