G-quadruplex aptamers with peroxidase-like DNAzyme functions: which is the best and how does it work?
Some G-quadruplex DNA aptamers have been found to strongly bind hemin to form DNAzymes with peroxidase-like activity. To help determine the most suitable DNAzymes and to understand how they work, five previously reported G-quadruplex aptamers were compared for their binding affinity and then the potential catalytic mechanism of their corresponding hemin-G-quadruplex DNAzymes was explored. Among these aptamers, a G-quadruplex named AGRO100 was shown to possess the highest hemin-binding affinity and the best DNAzyme function. This means that AGRO100 is the most ideal candidate for DNAzyme-based analysis. Furthermore, we found the peroxidase-like activity of DNAzyme to be primarily dependent on the concentration of H(2)O(2) and independent of that of the peroxidase substrate (that is, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt). Accordingly, a reaction mechanism for DNAzyme-catalyzed peroxidation is proposed. This study provides new insights into the G-quadruplex-based DNAzymes and will help us to further extend their applications in the analytical field.
Li
Tao
T
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022 (China).|Graduate School of the Chinese Academy of Sciences, Beijing, 100039 (China), Fax: (+86) 431-85689711.
Dong
Shaojun
S
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022 (China).|Graduate School of the Chinese Academy of Sciences, Beijing, 100039 (China), Fax: (+86) 431-85689711.
Wang
Erkang
E
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022 (China).|Graduate School of the Chinese Academy of Sciences, Beijing, 100039 (China), Fax: (+86) 431-85689711.
D052157:Aptamers, Nucleotide / Q000737:chemistry*; D001483:Base Sequence; D021881:DNA, Catalytic / Q000737:chemistry* / Q000378:metabolism; D054856:G-Quadruplexes; D006427:Hemin / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000378:metabolism; D007700:Kinetics; D010544:Peroxidases / Q000378:metabolism; D013056:Spectrophotometry, Ultraviolet
D052157:Aptamers, Nucleotide; D021881:DNA, Catalytic; D006427:Hemin; D006861:Hydrogen Peroxide; D010544:Peroxidases