Which characteristic is observed in Gram negative bacteria?

Gram negative bacteria are characterized by their unique cell wall structure, which consists of a thin peptidoglycan layer and an outer membrane containing lipopolysaccharide (LPS). One of the significant components of this outer membrane is the endotoxin, which can provoke strong immune responses in hosts. Endotoxins are integral to the structure of the bacteria and can be released when the bacterial cells are lysed, potentially causing complications in infections.

The other characteristics mentioned do not apply to Gram negative bacteria. Staining properties, such as the purple color that is observed in Gram positive bacteria due to their thick peptidoglycan layer, do not apply here. Gram negative bacteria typically stain pink or red after the Gram staining process, which is due to their thinner peptidoglycan layer that does not retain the crystal violet stain effectively. Therefore, the accurate understanding of Gram negative bacteria includes their production of endotoxins, which plays a crucial role in their pathogenicity.