Biochem/physiol Actions Lipid A molecules compose the lipid membrane anchoring core components of endotoxins produced by Gram-negative bacteria. Lipid A molecules induce immune responses. Structually, lipid A molecules are composed of two glucosamine unites with varied, species dependent, fatty acyl chain number and identity and degree of phosphorylation. Lipid A, diphosphoryl from Escherichia coli F583 may be used in comparative assessment of the antigenicity of specific structures within different LPA molecules and analogues. |