What type of bacteria typically contains endotoxins?

Endotoxins are a type of toxin that are part of the outer membrane of the cell wall of Gram-negative bacteria. These toxins are lipopolysaccharides (LPS) that are released when the bacteria are destroyed or undergo division. The presence of endotoxins is significant because they can trigger strong immune responses in the host organism, which can lead to fever, inflammation, and, in severe cases, septic shock.

In contrast, Gram-positive bacteria, which have a thicker peptidoglycan cell wall and no outer membrane, do not produce endotoxins. While aerobic and facultative anaerobic classifications describe the metabolic processes of bacteria, these categories do not inherently relate to the presence or absence of endotoxins. Therefore, Gram-negative bacteria's unique structure is what makes them the primary group that contains endotoxins. This distinction is critical in microbiology and medical interventions, especially regarding infection management and understanding the pathogenicity of different bacteria.