Application

Lipopolysaccharides (LPSs) are characteristic components of the cell wall of Gram-negative bacteria. LPS and its lipid A moiety stimulate cells of the innate immune system by the Toll-like receptor 4 (TLR4), a member of the Toll-like receptor protein family, which recognizes common pathogen-associated molecular-patterns (PAMPs).

Biochem/physiol Actions

Lipopolysaccharides (LPS) are localized in the outer layer of the membrane and are, in noncapsulated strains, exposed on the cell surface. They contribute to the integrity of the outer membrane, and protect the cell against the action of bile salts and lipophilic antibiotics.

General description

This product is a 0.2 um filtered aqueous solution containing 1 mg/mL of lipopolysaccharides (LPS) from E. coli serotype O55:B5. The source strain is CDC 1644-70. This LPS serotype has been used in studies of septic shock and to induce myocarditis.

Preparation Note

The LPS used to prepare the solution have been phenol-extracted and chromatographically purified by gel filtration. Lipopolysaccharides prepared by phenol extraction contain up to 60% RNA and less than 1% protein. Subsequent purification by gel filtration chromatography removes much of protein present in the phenol-extracted LPS, but leaves a product that still contains 10-20% nucleic acids. Further purification using ion exchange chromatography yields an LPS product which contains ﹤1% protein and ﹤1% RNA.