Design of a PCR method for rapid detection of Neisseria Meningitidis bacterium

Neisseria Meningitidis is a causative agent of the bacterial meningitis, a life-threatening disease in children and adults. There are several classic methods for the diagnosis of this bacterium but these are time consuming and unreliable. The goal of this present study was to establish a PCR based rapid detection for Neisseria meningitidis.

In this study the target gene was crgA so the specific primers were designed for it. The PCR reaction was set up on the DNA genomic of N meningitidis. To create a positive control, the PCR product was cloned in the pTZ57R/T vector. The presence of crgA gene in the T-vector was confirmed by the digestion and sequencing. The sensitivity of this assay was tested by a serial dilution of the positive control plasmid with starting concentration of 70ng/µl. The test specificity was checked by performing the PCR on the other bacterial genomes.

This test amplified a DNA fragment with expected size of 500bp. The results of the digestion and sequencing proved the presence of crgA gene in the T-vector. The result of the sensitivity study showed that 70pg was the lowest concentration of the positive control plasmid during PCR. The specificity results indicated no cross reaction with the genomic DNA of the other bacteria.

Results of this study showed a high specificity and sensitivity of PCR method for the rapid and precise detection of N. meningitidis. This assay as an important supplement would be substituted the previous molecular and time consuming phenotypic assays used in our laboratory and work. in contrast of.