A gyrB-based PCR for the detection of Vibrio vulnificus and its application for direct detection of this pathogen in oyster enrichment broths

A polymerase chain reaction (PCR) method based on the gyrB (encoding gyrase B or topoisomerase II) gene sequence was developed for the detection of Vibrio vulnificus in seafood. The gyrB primers detected all laboratory isolates of V. vulnificus and did not cross react with other Vibiro and non- Vibrio species examined in this study. The sensitivity of detection of V. vulnificus by gyrB PCR was 300 CFU/g in artificially seeded oyster homogenate without enrichment while, 30 CFU/g could be detected following 18 h enrichment in alkaline peptone water (APW). The gyrB-specific PCR was employed for the direct detection of V. vulnificus in oyster enrichment broths. The assay detected V. vulnificus in 75% of natural oyster samples after 18 h enrichment in APW. The gyrB-based PCR described here offers a simple and specific one step PCR method for the detection of V. vulnificus in seafood enrichment broths.