Lipopolysaccharide Chemotyping

Lipopolysaccharide (LPS), traditionally termed somatic antigen or O-antigen, forms an integral part of the outer membrane of Gram-negative bacteria. In general, LPS consists of essentially three parts:

1.	A hydrophobic portion, lipid A, which is composed of long-chain fatty acids and which anchors LPS molecules into the outer membrane;
2.	The core region; and
3.	The long-chain LPS, which is comprised of polymers of oligosaccharide units and contains the epitopes involved in LPS serotyping reactions.