Lipid
A -
Lipid A contains glucosamine, phosphate and fatty acids.
The carbohydrate component of lipid A consists of β-1, 6-D-glucosamine disaccharide units.
All the by droxyl and amino groups of the disaccharide are substituted. One of the substituents is the polysaccharidecl1.iJ.iit mentioned previously.
Two substituents are phosphates or pyrophosphates. The other substituents are fatty acids, which give lipid A its hydrophilic property.
There are six long chain fatty acid components of these lauric acid (12C), myristic acid (14C) and palmitic acid (16C) are present in the ratio of I: 1: 1.
In addition there are three molecules os 3-D-hydrnmyristic acid (14C).
Two of these have amide (-NH) linkages with each of the amino groups of the two glucosamine (GlcN) units.
The third is esterified through its hydroxyl group to myristic acid.
This chain is thought to be responsible for the fever-inducing properties of the LPS.
The fatty acid chains are presumed 10 penetrate the outer membrane and provide an anchor for the LPS.
