Development of a thermal-stable structure-switching cocaine-binding aptamer.
Biochimie
; 145: 137-144, 2018 Feb.
Article
en En
| MEDLINE
| ID: mdl-28838608
ABSTRACT
We have developed a new cocaine-binding aptamer variant that has a significantly higher melt temperature when bound to a ligand than the currently used sequence. Retained in this new construct is the ligand-induced structure-switching binding mechanism that is important in biosensing applications of the cocaine-binding aptamer. Isothermal titration calorimetry methods show that the binding affinity of this new sequence is slightly tighter than the existing cocaine-binding aptamer. The improved thermal performance, a Tm increase of 4 °C for the cocaine-bound aptamer and 9 °C for the quinine-bound aptamer, was achieved by optimizing the DNA sequence in stem 2 of the aptamer to have the highest stability based on the nearest neighbor thermodynamic parameters and confirmed by UV and fluorescence spectroscopy. The sequences in stem 1 and stem 3 were unchanged in order to retain the structure switching and ligand binding functions. The more favorable thermal stability characteristics of the OR3 aptamer should make it a useful construct for sensing applications employing the cocaine-binding aptamer system.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Cocaína
/
Aptámeros de Nucleótidos
/
Conformación de Ácido Nucleico
Idioma:
En
Revista:
Biochimie
Año:
2018
Tipo del documento:
Article
País de afiliación:
Canadá