ABSTRACT
Yersinia enterocolitica has been detected in surface water, and drinking untreated water is a risk factor for infection. PCR-based methods have been used to detect Y. enterocolitica in various sample types, but quantitative studies have not been conducted in water. In this study, quantitative PCR (qPCR)-based methods targeting the Yersinia virulence genes ail and yadA were used to survey the Grand River watershed in southern Ontario, Canada. Initial testing of reference strains showed that ail and yadA PCR assays were specific for pathogenic biotypes of Y. enterocolitica; however the genes were also detected in one clinical Yersinia intermedia isolate. A survey of surface water from the Grand River watershed showed that both genes were detected at five sampling locations, with the ail and yadA genes detected in 38 and 21% of samples, respectively. Both genes were detected more frequently at colder water temperatures. A screening of Yersinia strains isolated from the watershed showed that the ail gene was detected in three Y. enterocolitica 1A/O:5 isolates. Results of this study show that Yersinia virulence genes were commonly detected in a watershed used as a source of drinking water, and that the occurrence of these genes was seasonal.
Subject(s)
Adhesins, Bacterial/genetics , Bacterial Outer Membrane Proteins/genetics , Fresh Water/microbiology , Polymerase Chain Reaction/methods , Virulence Factors/genetics , Water Supply , Yersinia enterocolitica/genetics , Yersinia enterocolitica/isolation & purification , Colony Count, Microbial , DNA, Bacterial/analysis , OntarioABSTRACT
Yersinia enterocolitica is a foodborne pathogen, but the importance of water as a route of exposure for human infection is not well known. Y. enterocolitica isolation methods were developed primarily for food and clinical samples, and may not be effective for use with environmental samples. The objective of this study was to assess the recovery of Y. enterocolitica from surface water used for drinking water treatment. Four enrichment broths and an alkaline treatment protocol were compared for the isolation of Y. enterocolitica bioserogroup 4/O:3 spiked into surface water samples. Results showed that the methods tested were not effective for the recovery of Y. enterocolitica, primarily due to inadequate inhibition of interfering background microorganisms. Using one method that showed the most potential for recovery, Yersinia spp. were isolated from rivers in southwestern Ontario, Canada, over a 17-month period. Of 200 samples analysed, Yersinia spp. were isolated from 52 samples. All river isolates belonged to non-pathogenic sub-groups, including Y. enterocolitica biotype 1A, Y. aldovae, Y. bercovieri, Y. frederiksenii, Y. intermedia, Y. kristensenii and Y. mollaretii. Results of this study show that method improvements are required to more fully understand the role of water as a source of clinically important Yersinia strains.
Subject(s)
Fresh Water/microbiology , Water Supply , Yersinia enterocolitica/isolation & purification , Canada , HumansABSTRACT
The cytochrome p450 (CYP) superfamily is responsible for the oxidation, peroxidation, and (or) reduction of vitamins, steroids, xenobiotics, and the majority of cardiovascular drugs in an oxygen- and NADPH-dependent manner. Although hepatic CYP have been studied extensively, the role of CYP in cardiovascular physiology and disease is poorly understood. Increasing evidence suggests that these enzymes play an important role in the pathogenesis of a number of cardiovascular diseases. The current review summarizes the understanding as to the role that dysregulated CYP expression and (or) activity may play in the onset and progression of cardiovascular disease.