B. melitensis (Brucella melitensis) is a Gram-negative, aerobic, facultative intracellular bacterial pathogen that causes abortion in goats and sheep and Malta fever in humans. Species in the genus Brucella are the etiological agents of Brucellosis, a zoonotic disease endemic in many areas of the world, characterized by chronic infections in animals leading to abortion and infertility, and a systemic, febrile illness in humans. Brucella is facultative intracellular pathogens that enter the host through mucosal surfaces and are able to survive inside macrophages (Ref.1 & 2). The presence of S-LPS (Smooth Lipopolysaccharide) is an important virulence factor of these organisms. The role of the O-side chain or O-antigen of S-LPS in the survival of Brucella has not been clearly defined; however [...]