ABSTRACT
Aims@#Vibrio parahaemolyticus is a marine and estuarine bacterium that has been documented as the causative agent of food-borne outbreak worldwide. The aim of this study was to confirm the identification of presumptive V. parahaemolyticus isolates to the species level by using PCR targeted to the outer membrane protein regulation operon gene (toxR) and to investigate antibiotic resistance, plasmid profile, and the main core virulence genes of thermostable direct hemolysin (tdh) and tdh-related hemolysin (trh). @*Methodology and results@# A total of 56 presumptive isolates of V. parahaemolyticus were isolated from seawater collected during year a 2010 sampling pilot study performed along the Arabian Gulf coast of the Eastern Province of Saudi Arabia. The purpose of this study was to confirm the identification of presumptive V. parahaemolyticus isolates to the species level by using PCR targeted to the toxR gene and to investigate antibiotic resistance, plasmid profile, and the main core virulence genes of tdh and trh. The toxR-specific PCR assay revealed that a total of 30 out of 56 isolates tested positive for V. parahaemolyticus. None of the 30 strains of the toxR gene were tested positive for tdh and trh genes. All (100%) of isolates were highly resistant to amikacin, cefuroxime, ampicillin, ticarcillin, cefaclor (80%), and tetracycline (70%). The multiple antibiotic resistance (MAR) index was measured for all 16 antimicrobial agents, and the high ranged from 0.25 to 0.56. Among the isolated V. parahaemolyticus, 22 out of 30 strains contained plasmid DNA bands ranging in size from 1.5 to 55 kb and no correlation was observed between the plasmid profiles and antibiotic resistance patterns. @*Conclusion, significance and impact of study@#The results obtained in this study indicate that V. parahaemolyticus is present in the coastal environment of the Eastern Province of Saudi Arabia.
ABSTRACT
Objective To establish a method for the identification of Vibrio parahaemolyticus based on Taqman-fluorescence probe quantitative PCR method targeting toxR gene.Methods Taking the standard strain of Vibrio parahaemolyticus (VPJS421) and other ommon pathogenic bacteria'standard strain as the research object,using the bio-software to design specific PCR primers and Taqman probe of Vibrio parahaemolyticus toxR gene and detected by fluorescence quantitative PCR instrument.Results ①The designed primers could amplify specific bands.②The amplification efficiency of the 0.5 μl probe in the amplification system was better than that of the 1.0μl probe.③The detection sensitivity of toxR gene of Vibrio parahaemolyticus by Taqman fluorescence quantitative PCR was 10-1 mg/L.④The detection method did not show positive amplification in detection of Enterococcus f aecalis,Staphylococcus aureus,Saprophytic staphylococcus,Enterobacter hormaechei,Pseudomonas aeruginosa,Escheri ch ia coli,Vibrio al ginol yticus,Vibrio vulnficus,Vibrio metschnikovii and Wbrio furnissii 10 other common pathogenic bacteria.The specificity was 100％.Conlusion The fluorescence quantitative PCR method for the identification of Vibrio parahaemolyticus was successfully established.The method was sensitivty and specificity,and it is suitable for rapid detection of Wbrio parahaemolyticus and has a good application value.