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Brucella abortus is a facultative, intracellular zoonotic pathogen which can cause undulant fever in humans and abortions in cattle. A 14-kDa protein of B. abortus was previously identified to be immunogenic in animals infected with Brucella spp. In this study, we discovered that the 14-kDa protein possessed immunoglobulin binding and hemagglutination properties that appeared to be based on the protein's lectin-like properties. Hemagglutination inhibition experiments suggested that the 14-kDa protein has affinity towards mannose. Disruption of the gene encoding the 14-kDa protein in virulent B. abortus strain 2308 induced a rough-like phenotype with an altered smooth lipopolysaccharide (LPS) immunoblot profile and a significant reduction in the bacterium's ability to replicate in mouse spleens. However, the mutant strain was stably maintained in mouse spleens at 2.0 to 2.6 log 10 CFU/spleen from day 1 to week 6 after intraperitoneal inoculation with 4.65 log 10 CFU. In contrast to the case for the smooth virulent strain 2308, in the rough attenuated strain RB51 disruption of the 14-kDa protein's gene had no effect on the mouse clearance pattern. These findings indicate that the 14-kDa protein of B. abortus possesses lectin-like properties and is essential for the virulence of the species, probably because of its direct or indirect role in the synthesis of smooth LPS.The members of the Brucella genus are small, nonmotile, gram-negative, facultatively intracellular bacteria that can cause brucellosis in a variety of mammals. Brucellosis is a chronic zoonotic disease resulting in undulant fever in humans and abortion and/or infertility in affected animals. There are six species of Brucella that are currently recognized based on host specificity. They include Brucella abortus (cattle), B. melitensis (goats), B. suis (hogs), B. canis (dogs), B. ovis (sheep), and B. neotomae (wood rats) (7). Recently, Brucella has been isolated from a variety of marine mammals, including cetaceans (e.g., dolphins), seals, and otters (11).Brucella organisms can be phenotypically categorized based on their colony morphology into smooth, rough, and intermediate/mucoid types (7). Organisms characterized as smooth contain the O antigen (O-polysaccharide composed of perosamine polymers) in their lipopolysaccharide (LPS); true rough organisms do not express the O antigen. In general, smooth Brucella species are more virulent than their rough counterparts. B. canis and B. ovis are the only species of Brucella that naturally occur in the rough form and yet are still pathogenic in their host species. All four other named species naturally occur in the smooth form; the newly discovered marine isolates all appear to be smooth.The basis for the virulence of Brucella species can be attributed to the ability of these bacteria to escape the host defense mechanisms and to survive and replicate within host cells. Virulent Brucella organisms are capable of invading and replicating in professional phagocytes (4) such as macrophages as well as in nonphago...

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Currently, human cancer genomics is making great progress, and many mutations of new cancer driver genes have been detected at an unprecedented rate in a variety of human cancers. Many details of the genetic alterations in cancer cell genomes have been revealed by the massively parallel sequencing. Long-lasting aneuploidy caused large-scale somatic copy number alterations remains a difficulty as there are too many genes located on such big chromosomal fragments, and this cannot simply be solved by increasing sequencing depth and tumor sample numbers. Comparative oncogenomics may provide us with a solution to this problem. Here, we review some of the common animal cancer models and propose to analyze cancer cell genomics in vertebrate phylogenetic backgrounds. Thus phylooncogenomics may provide us with a unique perspective on he nature of cancer biology unattainable by single species studies.