Open AccessThis article is
- freely available
Selective Covalent Conjugation of Phosphorothioate DNA Oligonucleotides with Streptavidin
TU Dortmund, Fakultät Chemie, Biologisch-Chemische Mikrostrukturtechnik, Otto-Hahn Strasse 6, 44227 Dortmund, Germany
* Author to whom correspondence should be addressed.
Received: 26 June 2011; in revised form: 8 August 2011 / Accepted: 11 August 2011 / Published: 15 August 2011
Abstract: 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.
Keywords: nanobiotechnology; Protein-DNA conjugate; phosphorothioate; nuclease-stable
Citations to this Article
Cite This Article
MDPI and ACS Style
Rabe, K.S.; Niemeyer, C.M. Selective Covalent Conjugation of Phosphorothioate DNA Oligonucleotides with Streptavidin. Molecules 2011, 16, 6916-6926.
Rabe KS, Niemeyer CM. Selective Covalent Conjugation of Phosphorothioate DNA Oligonucleotides with Streptavidin. Molecules. 2011; 16(8):6916-6926.
Rabe, Kersten S.; Niemeyer, Christof M. 2011. "Selective Covalent Conjugation of Phosphorothioate DNA Oligonucleotides with Streptavidin." Molecules 16, no. 8: 6916-6926.