Gram-negative endotoxin: an extraordinary lipid with profound effects on eukaryotic signal transduction.
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.
Raetz
C R
CR
Department of Biochemistry, Merck Sharp and Dohme Research Laboratories, Rahway, New Jersey 07065.
Ulevitch
R J
RJ
Wright
S D
SD
Sibley
C H
CH
Ding
A
A
Nathan
C F
CF
D004731:Endotoxins / Q000737:chemistry / Q000494:pharmacology*; D005057:Eukaryotic Cells; D005786:Gene Expression Regulation; D006090:Gram-Negative Bacteria; D008264:Macrophages / Q000502:physiology / Q000648:ultrastructure; D015394:Molecular Structure; D011971:Receptors, Immunologic / Q000378:metabolism; D015398:Signal Transduction
D004731:Endotoxins; D011971:Receptors, Immunologic; C048071:endotoxin receptor