Kdo2-lipid A modification in Gram-negative bacteria—A review

Abstract:

Abstract:In most Gram-negative bacteria，the Kdo2-lipid A moiety of lipopolysaccharide forms the outer monolayer of the outer membrane．Diverse covalent modifications of Kdo2-lipid A may occur in bacteria to survive different environmental conditions．Kdo2-lipid A is usually synthesized on the cytoplasmic surface of the inner membrane．After the core oligosaccharide is attached to Kdo2-lipid A，the molecule is flipped to the outer surface of the inner membrane，where the O-antigen repeats are attached to form lipopolysaccharide．Kdo2-lipid A could activate the innate immune system through TLR4．Therefore，researches on the structure modification of Kdo2-lipid A would be useful for developing new vaccines and adjuvants.