Supramolecular aggregates of DNA, RNA, streptavidin, immunoglobulin, and nanocrystalline metal clusters can be generated by self-assembly on the basis of oligonucleotide hybridization (shown schematically). Following selective immunosorption on surface-immobilized antigen, the biometallic hybrid is detectable by electron microscopy.
Semisynthetic, covalent streptavidin-DNA adducts are versatile molecular connectors for the fabrication of both nano- and microstructured protein arrays by use of DNA hybridization. In this study, the hybridization characteristics of six adduct species, each containing a different DNA sequence of 21 or 24 bases, have been compared. First, the adducts were conjugated to biotinylated alkaline phosphatase, and their binding to immobilized oligomer complements of similar lengths was quantified in a microplate assay. The binding efficiency observed varied to a great extent with the specific sequence of the oligonucleotide attached, and could not be predicted from affiliated thermodynamic data of duplex stability. To further elucidate the hybridization properties, the hybridization rate constants of association and dissociation (kassn and kdissn) have been determined for both unconjugated oligonucleotides and protein adducts, using a surface plasmon resonance biosensor. The kassn values observed for the oligonucleotides are in the range of 9 x 10(3) to 2 x 10(5) M[-1] s(-1) and correlate with structural properties of the probe strands. Up to 3-fold decreased kassn values were obtained for the corresponding protein adducts. Likewise, values were observed for kdissn ranging from 1.4 x 10(-4) to 1.9 x 10(-5) s[-1] for the oligonucleotides. The dissociation of the analogous protein conjugates was reduced by up to 5-fold. The extent of this decrease correlates with the formation of homodimeric or intramolecular aggregation of probe strands. A mechanistic model for explaining these data is based on attractive intramolecular interaction between the nucleic acid and protein moiety.
Supramolekulare Aggregate aus DNA, RNA, Streptavidin, Immunglobulin und nanokristallinen Metallclustern können durch Selbstorganisation auf der Basis von Oligonucleotid‐Hybridisierung aufgebaut werden (siehe schematische Darstellung). Nach Immunosorption an Oberflächen‐immobilisiertes Antigen läßt sich das Biometallhybrid elektronenmikroskopisch nachweisen.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.