Genus Mycobacterium comprises a group of pathogenic, non-pathogenic and
environmental bacteria. The extensive host range of this genus is a remarkable
characteristic. Mycobacterium avian complex has a close relationship with
nonpathogenic groups and plays a significant role in the evolutionary study of these
bacteria. Tuberculosis, a noxious bacterial disease caused by M. tuberculosis, has
infected a large section of the population throughout the world, including India. M.
tuberculosis is the most successful pathogen of this genus that invades the host as a
parasite and survives within the macrophages of its host’s immune-cell lineage.
Tuberculosis is of prime concern to clinicians as the development of drug resistance is
a common phenomenon of this pathogen. Treatment of patients particularly infected
with the multi-drug-resistant and extensively drug-resistant strains are very difficult
with the available pool of antibiotics. Some alternative strategies, like the use of novel
phytochemicals, synthetic nano-drugs, etc., have proven promising to treat the
drugresistant strains.