someone diagnosed with meningitis has inflamed membranes that cover and protect the brain and spinal cord. meningitis is a result of pathogenic gram-negative bacteria that cause extreme infections when their bacterial cell wall dies and lipopolysaccharide (a lipid and polysaccharide) is released. the lipopolysaccharide is an example of a(n) endotoxin. exotoxin. stomach microbiota. parasite.