1. Inactivation and photoreactivation of blaNDM-1-carrying super-resistant bacteria by UV, chlorination and UV/chlorination.
- Author
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Yao, Shijie, Ye, Jianfeng, Xia, Jing, Hu, Yaru, Zhao, Xuetao, Xie, Jianhao, Lin, Kuangfei, and Cui, Changzheng
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CHLORINATION , *PLASMIDS , *REACTIVE oxygen species , *BACTERIAL cell surfaces , *SURFACE structure , *CELL membranes - Abstract
The excessive dissemination of New Delhi metallo-β-lactamase-1 (NDM-1), which mediates resistance to a majority of clinical β-lactam antibiotics, has created a major public health problem worldwide. Herein, a bla NDM-1 -carrying (plasmid encoded) super-resistant bacterium, Acinetobacter sp. CS-2, was selected to reveal its mechanisms of inactivation and photoreactivation during UV, chlorination and UV/chlorination disinfection. The inactivated CS-2 underwent a certain photoreactivation after UV and chlorination. The logistic model precisely fitted the data obtained in the photoreactivation experiments by UV treatment, with the estimated kinetic parameters S m (0.530%−12.071%) and k 2 (0.0009–0.0471). The photoreactivation of Acinetobacter sp. CS-2 was observed when treated by chlorination at a dosage of 0.5 mg/L with a survival ratio of 34.04%. UV/chlorination not only resulted in the high-efficiency reduction of CS-2 but also effectively controlled its photoreactivation with a survival ratio of 0%− 0.87%. UV/chlorination showed great advantages in causing the irreversible destruction of bacterial surface structures by making the cell membranes wrinkled and incomplete compared with UV disinfection. The singlet oxygen (1O 2) generated during UV/chlorination treatment played a vital role in bla NDM-1 removal. This study proposed new insights into the mechanism of inactivation and the characteristics of photoreactivation for the super-resistant bacteria by UV, chlorination and UV/chlorination. [Display omitted] • Logistic model precisely fitted photoreactivation experiments of superbug. • Photoreactivation and decay period were observed when treated by chlorination. • Irreversible destruction of cell surface structures by UV/chlorination treatment. • Singlet oxygen plays an important role on the plasmid-encoded bla NDM-1 removal. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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