Abhishek Kumar
T uberculosis is highly contagious bacterial disease caused by bacteria Mycobacterium tuberculosis. Presently, it is the second most deadly infectious disease in world. As per WHO report, in 2018, it was estimated that 10 million people suffer from this disease were died. Though, these stats have decreased from previous years but due to the lack of new antibiotics, delay in diagnosis and continuous use of all the available antibiotics bacteria developed multi-drug resistance (MDR) against the available antibiotics.
Mycobacterium is evolved to sustain in wide range of external environment due to biofilm formation. Biofilm is form due to the quorum sensing in the bacteria. The presence of quorum sensing in mycobacterium is indicated by the presence of LuxR homologus and expression pattern of transcription regulator, WhiB3. Quorum sensing occurred by signaling molecules secreted by bacteria to its immediate external environment and the molecule are concentrated as bacterial population increases. When concentration of auto-inducer reaches to threshold level then it regulates several types of genes and phenotypes, which include virulence and biofilm formation. Formation of biofilms is regulated by c-di-GMP which is secondary messenger in signal transduction. Biofilms are highly resistance to drugs.
Thus, new, stronger, improved anti-tubercular drugs are required. Along with that several improvements needs to be made to the available antibiotics like targeted drug delivery with application of nanotechnology for developing microspheres, liposome, noisome, microencapsulations, dendriemers, nanoparticles, solid lipid nanoparticles, nanostructured lipid carriers and discovery of enhancers for increasing efficacy of available antibiotics, development of genomics and bioinformatics in diagnosis of drug resistance TB and several developments in therapy are required to combat MDR in tuberculosis.