Characterization of Vibrio parahaemolyticus isolated from coastal water in Eastern Province of Saudi Arabia

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.

Improved isolation and detection of toxigenic Vibrio parahaemolyticus from coastal water in Saudi Arabia using immunomagnetic enrichment

“…The ERIC-PCR clusters indicate that the isolates could have originated from the same clonal lineage of V. parahaemolyticus . These results agreed with our previous study ( Elhadi & Nishibuchi, 2018 ) and are consistent with Marshall et al (1999) , who reported that ERIC-PCR was a useful method for evaluating genetic and epidemiological relationships among V. parahaemolyticus . The results obtained in this study are very significant for public health in this coastal region and should prompt us to pay attention to the role of these tdh positive V. parahaemolyticus in local foodborne diseases.…”

“…The highest percentage of tdh positivity was 17.5% from the total isolates detected among V. parahemolyticus isolated with IMB enrichment, while the lowest percentage of tdh positive isolates was (2.5%) detected in V. parahaemolyticus isolated without IMB enrichment ( Table 3 ). From our previous studies were conducted to investigate the presence of toxigenic V. parahaemolyticus in costal environment of the Eastern Province of Saudi Arabia, revealed none or less than 1% detection rate of isolates positive for virulence gene markers ( Elhadi & Nishibuchi, 2018 ; Ghenem & Elhadi, 2018 ). The detection of TDH positive strains of V. parahaemolyticus in the costal environment of the Eastern Province of Saudi Arabia is a pressing concern that has several impacts and requires instant attention.…”

“…DNA extraction was done for all selected colonies on TCBS and CaV agar isolated with and without IMB as described elsewhere ( Elhadi & Nishibuchi, 2018 ). Briefly, 1 ml of an overnight test culture in Luria Bertani (LB) broth was transferred into a 1.5 ml tube and centrifuged at 10,000 rpm for 2 min, and the supernatant was discarded.…”

“…Globally and compared with other foodborne illnesses, V. parahaemolyticus infections have been increasing and have become the leading cause of seafood bacterial infections ( Martinez-Urtaza et al, 2010 ; Abanto et al, 2020 ). In Saudi Arabia, no report of isolation of V. parahaemolyticus from any clinical cases and most of the reported isolation from environmental samples ( Elhadi, 2013 ; Elhadi & Nishibuchi, 2018 ; Ghenem & Elhadi, 2018 ).…”

Peer Review #2 of "Improved isolation and detection of toxigenic Vibrio parahaemolyticus from coastal water in Saudi Arabia using immunomagnetic enrichment (v0.1)"

“…DNA extraction was done for all selected colonies on TCBS and CaV agar isolated with and without IMB as described elsewhere (Elhadi et al, 2018). Briefly, 1 ml of an overnight test culture in Luria Bertani (LB) broth was transferred into a 1.5 ml tube and centrifuged at 10,000 rpm for 2 min, and the supernatant was discarded.…”