Temperature-robust and ratiometric G-quadruplex proximate DNAzyme assay for robustly monitoring of uranium pollution and its microbial biosorbents screening.


Yang Y(1), Yang H(2), Wan Y(3), Zhou W(4), Deng S(2), He Y(1), He G(2), Xie X(1), Deng R(5).
Author information:
(1)Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, No. 64, Mianshan Road, Mianyang 621900, China.
(2)College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China.
(3)Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Life and Pharmaceutical Sciences, Marine College, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 570228, China.
(4)Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, Hunan 410013, China.
(5)College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, China. Electronic address: [Email]


Uranium pollution in environment and food chain is a serious threat to public security and human health. Herein, we proposed a temperature-robust, ratiometric, and label-free bioassay based on G-quadruplex proximate DNAzyme (G4DNAzyme), accommodating us to precisely monitor uranium pollution and biosorption. The proximity of split G-quadruplex probes was proposed to sense UO22+-activated DNAzyme activity, thus eliminating the use of chemically labeled nucleic acid probes. And the simultaneous monitoring of G-quadruplex and double-stranded structures of DNAzyme probes contributed to a ratiometric and robust detection of UO22+. Particularly, the separation of enzymatic digestion and fluorescence monitoring endued a robust and highly responsive detection of UO22+ upon the temperature of enzymatic digestion process ranged from 18° to 41 °C. Consequently, G4DNAzyme assay allowed a robust, label-free and ratiometric quantification of uranium. We demonstrated the feasibility of G4DNAzyme assay for estimating uranium pollution in water and aquatic product samples. Ultimately, G4DNAzyme assay was adopted to serve as the platform to screen bacterial species and conditions for uranium biosorption, promising its roles in uranium associated biosafety control.