Molecular approach for rapid diagnostic kit to detect Yersinia pestis from infected soil, water sample

ABSTRACT

Yersinia pestis is the cause for the acute infection and may be chosen for biological terrorism. Rapid diagnosis of this agent from infected soil - water is essential. Y. pestis habours 3 specific plasmids providing virulent factors to the bacterium. Objectives: (1) Testing the sensitivity and accurateness of PCR for Y. pestis. (2) Carrying out PCR using total genomic DNA serially diluted as a template. (3) Undertaking PCR on artificical experimentation by diluting Y. pestis in soil water as samples to test PCR based fast diagnostic approach. Methods: Yersinia pestis (inactivated) was used. Genomic DNA was extracted by DNeasy kit (Qiagen Inc). Using primer - pairs PLAF - PLAR (binding on pia gene of plasmid pPCP1) a specific product of PCR was 480 bp. After determination of the PCR sensitivity, a molecular based diagnostic kit was developed. Sensitivity and specificity of this kit was tested by PCR using diluted genomic DNA and bacterium itself; and mix of these templates in water and soil as samples. Results: With the diluted genomic DNA, it was successful to obtain specific PCR with 0.6ng template, which is equal to a single bacterium. Additionally, successful PCR amplification was obtained using the whole bacterium (without extraction of genomic DNA) and diluted quantity ranging from 101 to 102. Based on these results, the bacterium was artificially diluted with sample of soil - water as a natural isolate for PCR amplification. Conclusions: Evidently, approach for PCR-based diagnostic kit was successfully carried out from any template including soil - water samples with high fidelity, using the pia gene genetic marker of pPCR of Y. pestis.