Isolation, identification, and molecular charac- terization of Brucella melitensis from aborted sheep fetuses in Kars, Turkey

Brucellosis is an emerging zoonosis and an economically important infectious disease of livestock with worldwide distribution [14]. The disease is manifested by abortion and infertility and caused by Brucella spp. which are Gramnegative, facultative intracellular bacteria. Six species in the genus of Brucella are currently recognized on the basis of the phenotypic characteristics, antigenic properties and host distribution [13]. Brucella melitensis is the main etiological agent of brucellosis in small ruminants and it can be responsible for bovine brucellosis in some areas [14, 23]. It is the most important and pathogenic Brucella sp. for humans causing clinically apparent human brucellosis. The disease is usually contracted by direct contact of the contaminated fetal tissues or consumption of contaminated unpasteurized milk or milk products. Brucellosis is geographically distributed in Mediterranean region, Middle East, parts of Africa, Western Asia and Latin America [8, 14, 20, 23]. B. melitensis is enzootic in different regions of Turkey and is the main cause of abortion in sheep [1, 2, 8, 9, 15, 20, 22-24]. The reports on brucellosis in Turkey are mainly diagnosed based on the isolation of the organism followed by identification with set of phenotypic tests, detection of Brucella DNA by Polymerase Chain Reaction (PCR) and serological tests [1, 2, 8, 9, 15, 20, 22-24]. However, B. melitensis strains isolated or detected in Turkey have not been genetically characterized in detail. The characterization of the causative agent of an infectious disease has a pivotal role in epidemiological studies, management of the outbreaks and implementing control and preventive measures. PCR-Restriction Fragment Length Polymorphism (RFLP) of Outer Membrane Protein (OMP) genes of Brucella has been widely and successfully used for genotyping of several Brucella isolates from geographically divergent regions including recent isolates from marine mammals [7, 10-12, 16].