Lipopolysaccharides, from S. enterica serotype typhimurium

Note:
1. To maintain the integrity of LPS, it is recommended to store LPS solution in silanized containers. This is because LPS can adhere to plastics and certain types of glass, particularly at concentrations below 0.1 mg/mL. If concentration of LPS is higher than 1 mg/mL, this adsorption effect is relatively small, it is recommended to prepare ≥2 mg/mL stock solution, vortex thoroughly for more than 10 minutes, and use ultrasound to assist dissolution if necessary, and ensure sufficient mixing and dissolution. If using glass containers, ensure that the solution is thoroughly mixed for at least 30 minutes before use to redissolve any LPS that may have adsorbed to the tube walls.
2. LPS is a molecule capable of forming micelles of varying sizes in solution, and its molecular weight is not fixed. Both the stock solution and working solution can be prepared directly based on mass concentration (mg/mL, μg/mL, etc.).
3. Upon dissolution in water or PBS, LPS may form a uniformly turbid solution. For sterilization, DO NOT filter the stock solution directly. It is recommended to dilute the stock solution to the working concentration before sterilizing through a 0.22 μm filter membrane.

Lipopolysaccharides, from S. enterica serotype typhimurium are lipopolysaccharides distinct from those secreted by common Salmonella species. The LPS of common Salmonella species has only one wild-type core oligosaccharide structure (the Ra core in serotype Typhimurium), whereas Lipopolysaccharides, from S. enterica serotype typhimurium differ from the Ra core in a single terminal branch of the outer core, which may determine different immunogenicity^[1]. S. enterica serotype typhimurium possesses two Wzz proteins: Wzz_ST (which sets the modal range of O-antigen to 16–35 repeat units^[RU]) and Wzz_fepE (which sets the modal value above 100 RU) (RU: sugar repeat units). The Wzz proteins regulate the length of the O-antigen in Lipopolysaccharides, and the number of RUs attached to lipid A is determined by the modal value set by the Wzz proteins. Mutations in the corresponding protein-coding genes lead to the formation of short-chain O-antigens and significantly reduce bacterial pathogenicity^[2].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.