Reagents, kits and applications for detection of Escherichia coli o157:h7 serotype pathogenic bacteria

Abstract

The invention discloses a reagent, a kit and application for detection of escherichia coli O157:H7 serotype pathogenic bacteria. The detection reagent comprises a primer pair mainly composed of a first primer and a second primer, and the sequences of the first primer and the second primer are correspondingly shown in SEQ ID NO:1 and SEQ ID NO:2. According to the detection reagent, whether the escherichia coli O157:H7 exists in a sample to be detected can be directly and simultaneously judged by naked eyes through color change generated by the oxidation-reduction reaction of substrates catalyzed through G-quadruplex nucleic acids mimic enzymes, the sensitivity of detecting foodborne pathogens is improved, dual strategies of introducing enzyme cycle signal amplification and PCR product amplification by using G-quadruplex nucleic acids mimic enzymes are used for achieving the amplification of a final signal, and the visual detection of escherichia coli O157:H7 is realized.

Description

technical field [0001] The invention particularly relates to a reagent, kit and application for detection of Escherichia coli O157:H7 serotype pathogenic bacteria, belonging to the technical field of detection of molecular biology methods. Background technique [0002] The public health problem caused by foodborne pathogenic microorganisms is a major problem in the world, and its missed detection rate is as high as 95%. According to WHO estimates, no less than 2 million deaths are caused by foodborne microbial infectious diarrhea worldwide each year, most of which are due to microbial contamination of diet and drinking water. Enterohemorrhagic Escherichia coli (EHEC) in food sources Sexually pathogenic microorganisms occupy an important hygienic position. [0003] EHEC Escherichia coli O157:H7 mainly exists in the intestinal tract of livestock and poultry for a long time, and human beings have been reported to be ill all over the world. Escherichia coli O157:H7 infection c...

AI Technical Summary

Problems solved by technology

However, the main limitation of this method is that the culture period of several days can provide accurate information on the nature of the strain or the isolate itself. PCR has been widely used to detect E. coli O157:H7 from food and environmental samples. Recently, real-time PCR has been used because of its enhanced The sensitivity and specificity and fast turnaround time are becoming more and more popular. The existing fluorescent quantitative method for detecting E. coli O157:H7 has a detection sensitivity of 80 CFU / ml, but the fluorescent quantitative PCR instrument used is expensive and expensive to use , still cannot meet the monitoring requirements at the grassroots level

The traditional PCR instrument needs to combine the gel electrophoresis method to analyze the size and brightness of the bands to judge, not only the detection sensitivity is not as good as the fluorescence quantitative PCR, but also there are cumbersome gel electrophoresis operation steps and the contamination of laboratory nucleic acid dyes

With the popularization of traditional PCR technology and the development of portable instruments, field detection becomes possible, but gel electrophoresis to observe the results is time-consuming and laborious and has certain biological hazards, which requires high requirements for experimental operators. Therefore, a traditional PCR-based method is urgently needed. Portable, rapid, sensitive, safe, and visualized detection methods to respond to future outbreaks in a timely and effective manner must have sufficiently sensitive, specific, and reliable methods for the rapid and convenient detection of E. coli O157:H7

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