title: Multiplexed real-time PCR amplification of tlh, tdh and trh genes in Vibrio parahaemolyticus and its rapid detection in shellfish and Gulf of Mexico water.
abstract: In this study, we have developed a SYBR Green I-based real-time multiplexed PCR assay for the detection of Vibrio parahaemolyticus in Gulf of Mexico water (gulf water), artificially seeded and natural oysters targeting three hemolysin genes, tlh, tdh and trh in a single reaction. Post-amplification melt-temperature analysis confirmed the amplification of all three targeted genes with high specificity. The detection sensitivity was 10 cfu (initial inoculum) in 1 ml of gulf water or oyster tissue homogenate, following 5 h enrichment. The results showed 58% of the oysters to be positive for tlh, indicating the presence of V. parahaemolyticus; of which 21% were positive for tdh; and 0.7% for trh, signifying the presence of pathogenic strains. The C(t) values showed that oyster tissue matrix had some level of inhibition, whereas the gulf water had negligible effect on PCR amplification. The assay was rapid (approximately 8 h), specific and sensitive, meeting the ISSC guidelines. Rapid detection using real-time multiplexed PCR will help reduce V. parahaemolyticus-related disease outbreaks, thereby increasing consumer confidence and economic success of the seafood industry.
authors.affiliation: Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294-1179, USA.
authors.forename: Amy V
authors.initials: AV
authors.lastname: Rizvi
authors.forename: Asim K
authors.initials: AK
authors.lastname: Bej
mesh_terms: D000818:Animals; D001267:Atlantic Ocean; D001426:Bacterial Proteins / Q000235:genetics* / Q000302:isolation & purification; D001427:Bacterial Toxins / Q000235:genetics / Q000302:isolation & purification; D052160:Benzothiazoles; D015342:DNA Probes; D004269:DNA, Bacterial / Q000032:analysis; D003959:Diamines; D005516:Food Microbiology; D005798:Genes, Bacterial; D006460:Hemolysin Proteins / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D017403:In Situ Hybridization; D009930:Organic Chemicals; D010125:Ostreidae / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D011804:Quinolines; D012623:Seawater / Q000382:microbiology*; D012680:Sensitivity and Specificity; D012758:Shellfish / Q000382:microbiology*; D014736:Vibrio parahaemolyticus / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D052160:Benzothiazoles; D015342:DNA Probes; D004269:DNA, Bacterial; D003959:Diamines; D006460:Hemolysin Proteins; D009930:Organic Chemicals; D011804:Quinolines; C088609:thermostable direct hemolysin-related hemolysin protein, Vibrio parahaemolyticus; C068489:thermostable direct hemolysin; C098022:SYBR Green I