Identification of Loa۲۲ coding gene in the vaccinal Leptospira serovars

Background and Aim : Leptospirosis is one of the most important zoonotic‎ diseases, which is caused by the Leptospira. Some Leptospra membrane lipoproteins perform as bacterial virulence factors. The aim of the present study was to molecular identification and investigation the presence of Loa۲۲ gene encoding a membrane lipoprotein in the vaccinal Leptospira serovars.Methods : In the present study, three vaccinal Leptospira serovars including L. Grippotyphosa, L. Canicola and L. Serjoe hardjo as well as a saprophytic serovar, L. Semanerga, were prepared. After DNA extraction by standard phenol-chloroform method and quantitative and qualitative analysis of the extracted DNA, PCR reaction was performed to amplify the Loa۲۲ gene. PCR products were evaluated by electrophoresis on agarose gel and finally sequenced. The resulting sequences were compared using Megalign software and the serovars genetic similarity was investigated.Results : The results of electrophoresis of PCR products showed ۶۷۱ bp bands indicating the presence of Loa۲۲ in vaccinal samples, while no band was formed in the saprophytic sample. The percentage of this gene similarity was high in pathogenic serovars so that the minimum similarity was ۹۷.۳% and the maximum similarity was ۹۹.۶%, which indicates the conservation of Loa۲۲ gene. Conclusion : Loa۲۲ gene is a specific conserved gene of vaccinal Leptospira serovars and can be used as a diagnostic marker to identify these serovars and differentiate them from the saprophytic ones.

کلیدواژه ها:

Leptospirosis ، Vaccinal Leptospira serovars ، Molecular identification ، Loa۲۲ gene