Evaluation of the virulence of Vibrio parahaemolyticus strains isolated in Russia and contiguous states
О А ШалуШалу Оксана АндреевнаЕ Н ГоленищеваЕ Н ГоленищеваЛ М СмоликоваЛ М СмоликоваГ В ГальцеваГ В ГальцеваН В БожкоН В БожкоE. V. MonakhovaE. V. MonakhovaО А ШалуО А ШалуYe N GolenishchevaGolenishcheva Ye NЛ М СмоликоваГ В ГальцеваН В БожкоYe V MonakhovaMonakhova Ye
1
Citation
0
Reference
20
Related Paper
Citation Trend
Abstract:
One hundred and ninety-six Vibrio parahaemolyticus strains that are etiological agents causing outbreaks and sporadic cases of food toxicoinfections and isolated from the environments of Russia, Ukraine, and Turkmenia are characterized by virulence-associated phenotypic and genotypic signs. Most clinical strains were found to contain the genes of the major pathogenicity factors - thermostable direct hemolysin (TDH) and/or TDH-related hemolysin (TRH); however, a large number of pathogens lack these genes. In all likelihood, these strains can cause human diseases, by producing other toxic substances. The presence of the trh gene correlated with that and expression of the urease genes. Comparative analysis of the findings has demonstrated that the results of polymerase chain reaction detection of the tdh gene do not always agree with the signs of hemolytic activity on the Wagatsum medium (Kanagawa phenomenon). Therefore, both tests that complement each other are recommended for a fuller evaluation of the potential danger of Vibrio parahaemolyticus strains.Keywords:
Hemolysin
Vibrio Infections
Objective To isolate pathogenes from stool samples of patients and other samples collected from food-processing tools in 3 food poisoning events,and identify the type and virulence gene of pathogens isolated. MethodsSuspect pathogen was isolated and identified in accordance with National Standard GB/T 4789-2003 and GB/T 4789.7 -2008;The detected Vibrio parahaemolyticus was tested for species-specific gene (320 bp),thermostable direct hemolysin gene (tdh 434 bp),tdh-related hemolysin gen (trh 250 bp) by PCR and thermolabile hemolysin gene (tlh 229 bp) by LAMP. Results Seven strains of V. parahaemolyticus was detected in 27 samples collected from patients,cooks and processing tools in 3 food poisoning events,including 6 strains from stool samples of patients and 1 strains from samples of processing tools. The serotype of 7 isolated V. parahaemolyticus strains were O10∶K66,O2∶K3,O1∶K33。 The isolates in each food poisoning events had the same biological characteristics,serotype and drug susceptibility test result and emerged Kanagawa phenomenon (KP),similar species-specific gene Vp bands were detected in tlh virulence genes,but the tdh,trh genes were negative. Conclusion It was confirmed the 3 food poisoning events were caused by the pollution of different serotype V. parahaemolyticu of tlh+/tdh-/trh-.
Hemolysin
Food poisoning
Thermolabile
Cite
Citations (0)
Hemolysin
Haemolysis
Vibrio Infections
Cite
Citations (39)
Forty clinical isolates of Vibrio parahaemolyticus were studied for the production of the thermostable direct hemolysin (TDH), and the TDH-related hemolysin (TRH) including the respective encoding genes, tdh and trh. The presence of TDH and its encoding genes were found amongst 95% of the strains, whereas the TRH was absent amongst these isolates. Thirty-two isolates were found to be plasmid-free, whereas eight isolates possessed plasmids with sizes ranging from 2.4 > or = 23 kb. Using a DNA probe coding for the homologous region of the tdh and trh, it was found that the tdh genes were present on the chromosomal DNA.
Hemolysin
Cite
Citations (5)
Hemolysin
Cite
Citations (0)
Hemolysin
Virulence factor
Cite
Citations (0)
ABSTRACT Virulence factor genes encoding the thermostable direct hemolysin ( tdh ) and the thermostable direct hemolysin-related hemolysin ( trh ) are strongly correlated with virulence of the emergent human pathogen Vibrio parahaemolyticus . The gene encoding the thermolabile hemolysin ( tlh ) is also considered a signature molecular marker for the species. These genes are typically reported in very low percentages (1 to 2%) of nonclinical strains. V. parahaemolyticus strains were isolated from various niches within a pristine estuary (North Inlet, SC) and were screened for these genes using both newly designed PCR primers and more commonly used primers. DNA sequences of tdh and trh were recovered from 48% and 8.3%, respectively, of these North Inlet strains. The recovery of pathogenic V. parahaemolyticus strains in such high proportions from an estuarine ecosystem that is virtually free of anthropogenic influences indicates the potential for additional, perhaps environmental roles of the tdh and trh genes.
Hemolysin
Thermolabile
Virulence factor
Cite
Citations (146)
Objective:To investigate the virulence gene change of Vibrio parahaemolyticus from 2006 to 2008 in Dongguan.Methods:PCR method and Kanagaw phenomenon method was used to detect the virulence gene.Results:The positive rate of tdh and trh gene in the Vibrio parahaemolyticus strains from food poisoning samples was 85.2%(127/149) and 8.7%(13/149),respectively.And it was 6.3%(3/48) and 2.1%(1/48) from the environment samples.The positive rate of Kanagaw phenomenon for all the Vibrio parahaemolyticus strains was 91.9%(137/149).Conclusion:The pathogenicity of Vibrio parahaemolyticus strains in Dongguan is very strong,and most of them from food poisoning include tdh gene.It is necessary to strengthen the surveillance of Vibrio parahaemolyticus.
Food poisoning
Cite
Citations (0)
Thermolabile
Hemolysin
Vibrio Infections
Cite
Citations (0)
Objective To understand the serotype and virulence genes of Vibrio parahaemolyticus isolated from patients of foodborne diseases and environment in Shenzhen. Methods There 133 Vibrio parahaemolyticus strains were isolated from patients of foodborne diseases and environment (such as the sea water and seafoods)during the years of 2006~2008, and were serotyped according to GB/T4789.7 -2008. Thermostable direct hemolysin gene (tdh) and thermostable direct hemolysin-related hemolysin gene(trh) wre also determined by PCR. Results O3(43.6%),O1(16.5%),O4(16.5%) were predominant serogroups. 84.4% (76/90)foodborne disease isolates carried tdh gene,and none carried trh gene only. 79.1%(34/43)environmental strains carried neither tdh nor trh,and none carried tdh and trh simultaneously. Conclusion In recent years,Vibrio parahaemolyticus causing foodborne disease carries tdh (+) and trh (-),and a majority of environmental isolates carry tdh(-)and trh(-)in Shenzhen.O3 was still the predominant serogroup.
Hemolysin
Cite
Citations (0)