Gram-negative endotoxin: an extraordinary lipid with profound effects on eukaryotic signal transduction

FASEB J. 1991 Sep;5(12):2652-60. doi: 10.1096/fasebj.5.12.1916089.


The lipid A domain of lipopolysaccharide (LPS) is a unique, glucosamine-based phospholipid that makes up the outer monolayer of the outer membrane of most gram-negative bacteria. Because of its profound pharmacological effects on animal cells, especially those of the immune system, lipid A is also known as endotoxin. Despite decades of earlier work, the precise chemistry of endotoxins and the biochemical pathways for their enzymatic synthesis have been elucidated only within the past 5 years. In this review, we summarize the essentials of endotoxin biochemistry and also present recent experiments aimed at identifying surface receptors, signal-transducing elements, transcriptional factors, and key intracellular targets involved in the response of animal cells to endotoxins.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Endotoxins / chemistry
  • Endotoxins / pharmacology*
  • Eukaryotic Cells*
  • Gene Expression Regulation
  • Gram-Negative Bacteria*
  • Macrophages / physiology
  • Macrophages / ultrastructure
  • Molecular Structure
  • Receptors, Immunologic / metabolism
  • Signal Transduction*


  • Endotoxins
  • Receptors, Immunologic
  • endotoxin receptor