Salmonella Enteritidis O-polysaccharide antigen (SE OAg)

The O-polysaccharide (O-antigen) of Salmonella Enteritidis is the distal, repeating carbohydrate component of the lipopolysaccharide (LPS) located on the bacterial outer membrane (NIH, 2024). It is composed of a trisaccharide backbone consisting of mannose, rhamnose, and galactose, with a unique alpha-3,6-tyvelose side chain that defines the O:9 serogroup specificity (NIH, 2024; ASM, 2026). This molecule plays a vital role in bacterial pathogenesis by protecting the organism from complement-mediated lysis and facilitating survival within host macrophages and the environment (ResearchGate, 2024; ASM, 2026). As a primary target of the host immune response, the O-antigen is the focus of various vaccine development efforts, including glycoconjugate vaccines and live attenuated strains (PLOS, 2024; Frontiers, 2024). These vaccines aim to elicit high-titer, functional antibodies that enhance bacterial clearance through opsonization and bactericidal activity (Scilit, 2024; NIH, 2024).

Other names

Salmonella Enteritidis O-antigenSomatic antigen 9O:9 antigenSalmonella Enteritidis OPSLipopolysaccharide O-side chain

Induction of serovar-specific antibodies (IgG, IgM) that promote opsonophagocytosis and complement-mediated killing of the bacteria.