Tuberculosis is a major global health challenge and is far from being controlled. Development of resistance to currently available drugs due to the successful adaptation of the pathogen has been a major contributing factor for its control failure. Presently, there is an immense interest in identification of pathways, unique to the intracellular environment that could be utilized for the development of new and better drugs. In this sequence, targeting essential functions of Mycobacterium tuberculosis has emerged as a reliable strategy for containing the spread of the disease by this organism. The fact that iron has been known to be the key player required for its survival and ability to spread infection, the organism must carefully balance iron acquisition with iron uptake for its infectivity. Conversely, this iron homeostatic process could be disrupted to interfere with the survival and replication of this bacterium in host. Urgency to develop such an approach has been further strengthened with the worldwide recrudescence of tuberculosis especially in the developing nations of the world. In the current review, we have focused on the recent developments in targeting the essential functions of mycobacterium especially interfering in its iron homeostatic process. The relevance of iron for mycobacterial virulence, the intracellular survival and the immense potential of targeting iron-sulfur (Fe-S) cluster containing proteins in tuberculosis drug discovery has been discussed.

Nanobiotechnology is the innovative field of science which involves biological synthesis, characterization and application of numerous nanoparticles. The present study was planned to explore potential of endophytic fungi for eco-friendly synthesis of silver nanoparticles with antibacterial activity. In this study 8 endophytic fungal isolates were obtained from different parts of medicinal plants. These isolates were identified belonging to different genera namely, Penicillium, Aspergillus, Alternaria etc. All endophytic fungi were subjected to extra cellular biosynthesis of silver nanoparticles. Out of these Penicillium sp.,Aspergillus sp., Alternaria sp., isolated from healthy plant parts of Aegle marmelos, Dalbergia sissoo and Lantana camara respectively, gave positive results. The antibacterial activities of these nanoparticles were determined against some pathogenic bacteria by Agar Well Diffusion assay. During which it was found that the silver nanoparticles sample exhibiting highest antibacterial potential was characterized by UV-Visible Spectroscopy, Dynamic Light Scattering (DLS), Zeta Potential analysis and Transmission Electron Microscopy. UV-Visible spectroscopy analysis gave surface plasmone resonance peak alternatively 416nm, 444nm and420nm.The average size range of silver nanoparticles as determined via, dynamic light scattering analysis is: 126nm, 88nm, 141nm. The Zeta potential of three samples as determined by zeta sizer showed a high negative surface charge on them which confers stability to them. The zeta potentials of these particles are: -19.1 mV, -22.0 mV, -16.2 mV. Silver nanoparticles produced by endophytic fungi displays considerable antibacterial agent and hence the study would prove to provide novel antibacterial agents.