Back to Search
Start Over
Selection, Characterization and Application of Artificial DNA Aptamer Containing Appended Bases with Sub-nanomolar Affinity for a Salivary Biomarker.
- Source :
-
Scientific reports [Sci Rep] 2017 Mar 03; Vol. 7, pp. 42716. Date of Electronic Publication: 2017 Mar 03. - Publication Year :
- 2017
-
Abstract
- We have attained a chemically modified DNA aptamer against salivary α-amylase (sAA), which attracts researchers' attention as a useful biomarker for assessing human psychobiological and social behavioural processes, although high affinity aptamers have not been isolated from a random natural DNA library to date. For the selection, we used the base-appended base (BAB) modification, that is, a modified-base DNA library containing (E)-5-(2-(N-(2-(N6-adeninyl)ethyl))carbamylvinyl)-uracil in place of thymine. After eight rounds of selection, a 75 mer aptamer, AMYm1, which binds to sAA with extremely high affinity (K <subscript>d</subscript> < 1 nM), was isolated. Furthermore, we have successfully determined the 36-mer minimum fragment, AMYm1-3, which retains target binding activity comparable to the full-length AMYm1, by surface plasmon resonance assays. Nuclear magnetic resonance spectral analysis indicated that the minimum fragment forms a specific stable conformation, whereas the predicted secondary structures were suggested to be disordered forms. Thus, DNA libraries with BAB-modifications can achieve more diverse conformations for fitness to various targets compared with natural DNA libraries, which is an important advantage for aptamer development. Furthermore, using AMYm1, a capillary gel electrophoresis assay and lateral flow assay with human saliva were conducted, and its feasibility was demonstrated.
Details
- Language :
- English
- ISSN :
- 2045-2322
- Volume :
- 7
- Database :
- MEDLINE
- Journal :
- Scientific reports
- Publication Type :
- Academic Journal
- Accession number :
- 28256555
- Full Text :
- https://doi.org/10.1038/srep42716