LipopolysaccharideMoleküle

Lipopolysaccharide, often abbreviated as LPS, is a complex molecule found in the outer membrane of Gram-negative bacteria. It is a major component of the bacterial cell wall and plays a crucial role in the structural integrity of these microorganisms. LPS is composed of three distinct regions: lipid A, the core oligosaccharide, and the O-antigen.

Lipid A is the innermost component and is embedded within the bacterial membrane. It is responsible for the molecule's endotoxic properties, meaning it can trigger a strong inflammatory response in the host organism when released from the bacteria. The core oligosaccharide is a branched chain of sugars that connects lipid A to the O-antigen. The O-antigen is the outermost and most variable part of LPS, extending outwards from the bacterial surface. This region is highly diverse among different bacterial species and even strains, and it is a key factor in determining the bacterial serotype.

The presence of LPS in the outer membrane contributes to the barrier function of Gram-negative bacteria, protecting them from certain environmental stresses and the host's immune system. However, when Gram-negative bacteria are lysed or their membranes damaged, LPS can be released into the surrounding environment. This release is a significant trigger for the innate immune system, initiating a cascade of inflammatory responses that can lead to symptoms such as fever, shock, and disseminated intravascular coagulation. Research into LPS continues to be important for understanding bacterial pathogenesis and developing new therapeutic strategies against infections.