Application of real-time PCR for quantitative detection of Vibrio parahaemolyticus from seafood in eastern China.
Vibrio parahaemolyticus is recognized as a leading human food-borne pathogen. A TaqMan PCR assay based on the gyrase B gene (gyrB) sequence of V. parahaemolyticus was developed for quantitative detection of V. parahaemolyticus in seafood. The study involving 27 V. parahaemolyticus and 10 strains of other species indicated that the real-time PCR test was highly specific. The sensitivity of the assay was approximately a single CFU per PCR in pure culture and six to eight CFU per PCR in spiked raw oyster, respectively. Real-time PCR values of artificially inoculated oyster homogenates correlated well with plate counts determined using culture methods. A total of 300 seafood samples were analyzed and 78 (26%) of these samples were positive for V. parahaemolyticus using a conventional culture method and 97 (32.3%) using the real-time PCR assay. All culture-positive samples were PCR-positive. However, 19 samples positive by PCR were culture-negative. The results show that retail seafood is commonly contaminated with V. parahaemolyticus in harvest season in eastern China. These data also indicate that real-time PCR can provide sensitive species-specific detection and quantification of V. parahaemolyticus in seafood without prior isolation and characterization of the bacteria by traditional microbiological methods.
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
Tanxi
T
Cai
Luyan
L
Jiang
Chengbo
C
Yang
Kehe
K
Huang
D000818:Animals; D049872:Bivalvia / Q000382:microbiology*; D002681:China; D015342:DNA Probes; D004269:DNA, Bacterial / Q000032:analysis; D005399:Fishes / Q000382:microbiology*; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*; D017747:Seafood / Q000382:microbiology*; D012680:Sensitivity and Specificity; D019914:Taq Polymerase; D014736:Vibrio parahaemolyticus / Q000235:genetics / Q000302:isolation & purification*
D015342:DNA Probes; D004269:DNA, Bacterial; D019914:Taq Polymerase