Shigella sonnei lipopolysaccharide (S. sonnei LPS)

Shigella sonnei lipopolysaccharide is a complex amphipathic glycolipid forming the outermost layer of the outer membrane of Gram-negative *Shigella sonnei*. It consists of three structural domains: lipid A (a phosphorylated, acylated glucosamine disaccharide responsible for endotoxic effects), a conserved core oligosaccharide (contains Kdo, heptoses, and hexoses), and a serotype-specific O-antigen polysaccharide (composed in S. sonnei of repeating units containing 2-acetamido-2-deoxy-L-altruronic acid and 2-acetamido-2-deoxy-L-fucose). The O-antigen functions as the immunodominant and protective antigen, critical for immune evasion and as a vaccine target. The genetic determinants for the O-antigen are plasmid-encoded and structure-specific for S. sonnei. Antibodies targeting the O-antigen can prevent infection, making LPS a central focus for vaccine and immunotherapeutic development.

Other names

Shigella sonnei LPSS. sonnei LPSShigella sonnei O antigenS. sonnei O polysaccharide

Vaccines elicit antibodies that bind the *O-specific polysaccharide* and block infection via opsonization, complement activation, and neutralization. Antibiotics targeting LPS biosynthesis (e.g., LpxC inhibitors) interfere with cell wall construction, leading to bacterial death.