Y pseudotuberculosis and Y enterocolitica Assays

The high degree of homology between Y. pestis and Y. pseudotuberculosis at the DNA level makes development of molecular assays specific for the latter organism difficult. The 16S rRNA sequence is identical for these bacterial species. A 1 base pair difference was noted in the 23S rRNA gene, and an assay has been developed based on this polymorphism.[16]

Y. enterocolitica is a more important foodborne pathogen than is Y. pseudotuberculosis, and therefore more assays have been developed to detect this species (Table 3). The 16S rRNA sequence is significantly different from the other pathogenic Yersinia so that this makes a convenient higher copy number target. One

Table 3 Partial list of published molecular diagnostic tests for Yersinia

Organism Target Method Sensitivity Comments Reference

Y. pestis pla Standard PCR 10 CFU/reaction Early molecular diagnostic [19]

developed based on Y. pestis specific gene

Y. pestis pla Fluorogenic PCR ~ 850 copies/reaction Detection limit based [20]

on purified

DNA; specific detection obtained in fleas, blood, tracheal fluid, serum, and swabs

Y. pestis and pla, caf1, inv, Standard PCR ~ 80 CFU/reaction Useful assays for [21]

Y. pseudotuberculosis and yopM differentiation of closely related species of this genus

Y. pestis pla and caf1 Standard PCR ~ 10-50 CFU/reaction PCR assays developed [22]

for two species-specific genes

Pathogenic Yersinia rRNA Fluorogenic ~ 100 CFU/mL Suitable for identification [16]

probes, PCR of infected tissues and in situ hybridization

Y. enterocolitica rRNA Fluorogenic PCR 10 CFU/mL Sensitive method suitable for [23]

detection in blood samples

Y. enterocolitica rRNA and ail Standard PCR ~ 1 CFU/reaction Duplex PCR using two [17]

specific targets

Y. enterocolitica yst Fluorogenic PCR 100 CFU/reaction Good for identification of [24]

some pathogenic strains of the organism group has combined this target with the ail gene that is specific for only pathogenic strains of Y. enterocolitica.[17]

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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