Color enhanced transmission electron micrograph (TEM) of Neisseria meningitidis. N. meningitidis is a gram-negative bacteria that infect the human nasopharynx, causing meningitis and meningococcal disease. The bacteria is responsible for mortality in developing countries. Symptoms begin with fatigue and develop into fever, headache, neck stiffness and then coma and death. Magnifcation 50,000x at 10 cm.