A propidium monoazide-polymerase spiral reaction (PMA-PSR) designed for direct detection of Escherichia coli O157:H7 viable cell

• DOI: 10.1016/j.lwt.2023.115212
• Publication Date: 2023-08-19T06:29:45Z
• Authors: Junyan Liu; Tengyi Huang; Riyi Xu; Zhufang Xiang; Thanapop Soteyome; Xiangyi Chen; Qianfei Zhang; Qiurong Huang; Zixu Wu; Yunyi Huang; Gongliang Liu; Chunyun Qu; Gamini Seneviratne; Birthe V. Kjellerup; Zhenbo Xu
• Keywords: Propidium monoazide; STX2; Foodborne pathogen

Escherichia coli O157:H7 is a major foodborne pathogen causing food poisoning. Standard detection method for E. plate counting, which time consuming and omits VBNC cells. PSR an isothermal amplification technique identifying trace amount DNA. However, its effectiveness influenced by residual DNA from dead This study aimed at designing PMA-PSR system accurate determination of viable cells O157:H7. Firstly, was optimized in fluorescence indicator, betaine concentration reaction time. The could successfully identify rfbE, stx1 stx2 genes within 45 min 65 °C. Secondly, sensitivity specificity were tested pure culture different samples. With 100% specificity, determine as low 1.12 pg/μL. Thirdly, designed Cells treated with 5 μg/mL PMA to remove Pretreated adapted PSR, thus specifically detected. Fourthly, the applied samples Viable be accurately determined accordance regular assay. In conclusion, efficient tool