Which of the Following is Released by Dying Gram-Negative Bacteria

Question

Which of the following is released by dying Gram-negative bacteria, whereupon it acts as endotoxin?
A) peptidoglycan
B) O-polysaccharides
C) porin proteins
D) pentaglycine
E) lipopolysacharides

Accepted Answer

Lipopolysaccharides (LPS) are components of the outer membrane of Gram-negative bacteria. When these bacteria die, their LPS is released and acts as an endotoxin, triggering an immune response in the host organism. Peptidoglycan, porin proteins, and pentaglycine are components of the bacterial cell wall, but they are not released specifically by dying Gram-negative bacteria and do not act as endotoxins. O-polysaccharides are components of the LPS molecule, but they do not specifically act as endotoxins when released by dying Gram-negative bacteria.