Mycobacterium smegmatis, a gram positive bacterium, is considered a non-pathogenic
microorganism. It does not cause disseminated disease even in immuno-suppressed individuals.
In some very rare cases, it may cause disease because it is related to immunosuppression. It
grows at a relatively high rate in many defined and nutrient-restricted media. As a result, M.
smegmatis has been used as an appropriate model for studying the pathogenesis of tuberculosis