Brucella abortus is a Gram-negative alpha-proteobacterium in the family Brucellaceae and is one of the causative agents of brucellosis. Lipopolysaccharides (LPS), also known as lipoglycans and endotoxins, are large molecules consisting of a lipid and a polysaccharide composed of O-antigen, outer core and inner core joined by a covalent bond; they are found in the outer membrane of Gram-negative bacteria, and elicit strong immune responses in animals.