SAE carried out the molecular genetic work and drafted the manuscript. Both authors read and approved the final manuscript.”
“Background Brucellosis is primarily a zoonotic disease, caused by members of the genus Brucella, which currently constitutes several species based on pathogenicity, host preferences and phenotypic characteristics: E1 Activating inhibitor B. abortus (cattle), B. canis (dogs), B. RG-7388 melitensis (goats), B. suis (pigs), B. ovis (rams), B. neotomae (desert rats), B. ceti and

B. pinnipedialis (marine mammals), and B. microti (common vole) [1–6]. Recently, a novel species, Brucella inopinata, associated with a human infection has been recognized as the newest member of the genus Brucella [7, 8]. In early 1985, whole genome hybridization analysis studies revealed a high degree of genetic homology among the Brucella species, which led to the proposal that the genus Brucella was a mono-specific species with B. melitensis being the primary species and all others as sub-species and biovars [9–11]. However, due to the limited acceptability of the one-species concept, the traditional classification of Brucella OSI 906 spp. based on phenotypic characteristics has been re-instated by the Brucella Taxonomy Subcommittee in 2006 [3].

Brucella are facultative intracellular pathogens that infect many organs and soft tissues, including mammary glands. Infection frequently results in abortion, low milk production and fetal death in animals [2, 12–16]. Brucellosis in humans is mostly caused by B. abortus, B. melitensis, B. suis, and sometimes B. canis [14, 17–19], and is commonly associated with the consumption of unpasteurized dairy products, meat from infected animals and exposure to infected animal tissues or laboratory transmission [1, 2, 20]. Human brucellosis is a chronic debilitating infection with a very broad clinical picture potentially affecting any major organ, including the lung, causing varying respiratory symptoms [20]. Respiratory infections in humans caused by Brucella spp. is a rare manifestation with reports describing multifocal abscesses or nodules, hilar adenopathy and hemorrhagic pleural effusion with resolution

by antimicrobial therapy and lung decortications [21–26]. Most pulmonary brucellosis RVX-208 cases were found in farmers handling infected meat or travelers who consumed raw infected animal meat or unpasteurized milk products while visiting countries endemic for brucellosis [26, 27]. We report the isolation and identification of an unusual gram-negative, non-motile Brucella-like coccoid bacillus (BO2) isolated from a lung biopsy in a 52-year-old male in Australia with a history of chronic destructive pneumonia. The patient traveled worldwide but denied any common risk factors associated with brucellosis. Both biochemical and molecular characteristics of the BO2 strain have demonstrated unique similarity with a recently described B.