Selective Covalent Conjugation of Phosphorothioate DNA Oligonucleotides with Streptavidin

Molecules

Kersten S. Rabe¹ 

[1] TU Dortmund, Fakultät Chemie, Biologisch-Chemische Mikrostrukturtechnik, Otto-Hahn Strasse 6, 44227 Dortmund, Germany

关键词: nanobiotechnology;    Protein-DNA conjugate;    phosphorothioate;    nuclease-stable;   

DOI  :  10.3390/molecules16086916

来源: mdpi

【 摘 要 】

Protein-DNA conjugates have found numerous applications in the field of diagnostics and nanobiotechnology, however, their intrinsic susceptibility to DNA degradation by nucleases represents a major obstacle for many applications. We here report the selective covalent conjugation of the protein streptavidin (STV) with phosphorothioate oligonucleotides (psDNA) containing a terminal alkylthiolgroup as the chemically addressable linking unit, using a heterobifunctional NHS-/maleimide crosslinker. The psDNA-STV conjugates were synthesized in about 10% isolated yields. We demonstrate that the terminal alkylthiol group selectively reacts with the maleimide while the backbone sulfur atoms are not engaged in chemical conjugation. The novel psDNA-STV conjugates retain their binding capabilities for both biotinylated macromolecules and the complementary nucleic acid. Moreover, the psDNA-STV conjugate retained its binding capacity for complementary oligomers even after a nuclease digestion step, which effectively degrades deoxyribonucleotide oligomers and thus the binding capability of regular DNA-STV conjugates. The psDNA-STV therefore hold particular promise for applications e.g. in proteome research and novel biosensing devices, where interfering endogenous nucleic acids need to be removed from analytes by nuclease digestion.

【 授权许可】

CC BY   
This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.