The genomic analysis of Brucella melitensis field isolates based on OMP۳۱ gene

Background and Aim : Brucella melitensis is the global pathogenic species of Brucella that contributed to ovine, caprine and, human brucellosis.The gene of omp۳۱encodes the major ۳۱-kDa Brucella Outer Membrane Proteins of B. melitensis and play important roles indirectly interacting with host cells but littleinformation is available on genomic analysisof these proteins in different serovars of B. melitensisand different hosts of human, goat, sheep cattle and camel in Iran. The purpose of the project is to know the genomic characterization of the omp۳۱ based PCRfrom Iranian isolates of B. melitensis in this study. Methods : ۱۴۶ samples were selected from human blood samples, bovine and camel lymph nodes as well assheep and goat aborted fetuses including fetal kidney, abomasum, liver, lung, spleen, andheart for bacteriological investigation. The molecular detection of omp۳۱ and IS۷۱۱ gene were performed using theisolated B. melitensis (n=۱۴). Sequencing of omp۳۱ gene of B. melitensisin Iranian field isolates was performedfor whole gene sequencing. The omp۳۱ gene of ۱۴Iranianhuman and animal field isolatesof B. melitensis were analyzed for the presence of nucleotidevariations by PCR amplification and sequence analysis and the results confirmed with AMOS- PCR assay.Results : Our results showed thatB. misolates were recovered from ۱۴ examined cases and confirmed by the IS۷۱۱ based-PCR with a PCR product of ۷۳۱ bp.The ۱۴ Iranian B.melitensis sequences clustered together as a monophyletic grouping with abootstrap support of ۶۳, and they are most closely related to the B. melitensis references isolates. Conclusion : This omp۳۱ based phylogenetic placement powerfullyindicates a monophyletic origin of Iranian B. melitensis in different animals and human hosts. Our data may help to develop improved diagnostic tools and a subunit vaccine candidatefor the control of brucellosis.

Keywords:

Brucella melitensis , omp۳۱gene , PCR , Genomics