Detection of Campylobacter jejuni based on CRISPR/Cas12a with novel target yclQ obtained by pan-genome analysis

Campylobacter jejuni (C. jejuni) is one of the most common causes of bacterial gastrointestinal foodborne infections worldwide. Conventional detection methods based on bacterial culture are time-consuming, therefore, rapid detection methods are urgently needed to be developed. The objective of this study was to screen a novel species-specific target and to develop a rapid and accurate method for the detection of C. jejuni in food. Through pan-genome analysis of 298 Campylobacter whole-genome sequence data, a new species-specific target yclQ was screened. The yclQ gene was verified through PCR to be unique to C. jejuni. Subsequently, based on the target yclQ, we developed of a CRISPR/Cas12a-based platform for fluorescence visualization and nucleic acid test strips. The RAA-CRISPR/Cas12a system demonstrates the ability to detect C. jejuni at 1.8 CFU/mL within 50 minutes. Compared to PCR (1.8×101 CFU/mL), the RAA and RAA-CRISPR/Cas12a assay showed higher sensitivity. The detection results of the actual samples were consistent with those of the isolation and culture procedures. In conclusion, the RAA-CRISPR/Cas12a system, based on the target yclQ, demonstrates significant potential for the rapid and accurate detection of C. jejuni in food.