Cloning And Sequence Analysis Of The B2L Gene Of Contagious Ecthyma Virus Isolates And Diagnosis Of CEV By PCR

The OV/nm-05 virus was propagated and the total DNA of virus was extracted. According to the published B2L gene sequence of CEV strain in GenBank, one pair of primer was designed. The B2L gene of virus was amplificated with the primer by PCR and then cloned into pMD18-T plasmids and then sequenced and analysed in homology. The acquired sequences contained 1133bp, The homology analysis revealed that the homology of the strain NZ2 and the OV/nm-05 was 97.9%, the N86.20a and the OV/nm-05 was 84.2%. There were a little variation between OV/nm-05 strain and the referenced virus strains.According to the published sequence of strain NZ2 in GenBank, another pair of primer was designed. The virus DNA was amplificated with the primer by PCR, then PCR diagnostic method was established, and this method's specificity and sensitivity was detected. The results indicated that the PCR method could detect the nucleic acid of OV/nm-05 virus only and a 440bp DNA fragment was amplificated. The minimum CEV DNA's detection level was 1.1ng. This illustrated that this method was specific and sensitive for the detection of CEV.