Exp Mol Med.  2013 Dec;45(12):e66.

Recognition of lipopolysaccharide pattern by TLR4 complexes

• Park BS
• Lee JO

Abstract

Lipopolysaccharide (LPS) is a major component of the outer membrane of Gram-negative bacteria. Minute amounts of LPS released from infecting pathogens can initiate potent innate immune responses that prime the immune system against further infection. However, when the LPS response is not properly controlled it can lead to fatal septic shock syndrome. The common structural pattern of LPS in diverse bacterial species is recognized by a cascade of LPS receptors and accessory proteins, LPS binding protein (LBP), CD14 and the Toll-like receptor4 (TLR4)-MD-2 complex. The structures of these proteins account for how our immune system differentiates LPS molecules from structurally similar host molecules. They also provide insights useful for discovery of anti-sepsis drugs. In this review, we summarize these structures and describe the structural basis of LPS recognition by LPS receptors and accessory proteins.

Keyword

lipopolysaccharide (LPS); Toll-like receptor 4 (TLR4); MD-2; CD14; LBP

MeSH Terms

Amino Acid Sequence
Animals
Binding Sites
Carbohydrate Sequence
Humans
Immunity, Innate
Lipopolysaccharides/*chemistry/immunology/pharmacology
Molecular Sequence Data
Toll-Like Receptor 4/*chemistry/immunology/metabolism
Lipopolysaccharides
Toll-Like Receptor 4