Which of the following organism does not satisfy Koch's postulate?: (A) M.TB, (B) M.Lepra, (C) M.Avium, (D) Pneumococcus
Answer is B. It is not possible to culture M.Lepra in culture medium, so it doesnt follow Koch's postulate. Koch's postulate defines the criteria for establishing a causal relationship between a suspect pathogen and disease. According to the postulate a suspected bacterium must be found in all organisms suffering from the disease but not healthy ones, suspected bacterium must be isolated from a diseased organism, isolated bacterium should cause disease when introduced into a healthy organism and bacterium must be reisolated from the diseased organism. Ref: Textbook of Microbiology By Ananthanarayan And Paniker, 7th edition page 370.