Mechanisms of biofilm-based antibiotic resistance and tolerance in Mycobacterium tuberculosis

Mycobacterium tuberculosis is foremost public health issues globally, and the emergence of multidrug resistance (MDR) and extensively drug resistance tuberculosis (XDR-TB) has further worsened the situation. Eradication of tuberculosis (TB) has become increasingly difficult due to the acquisition of the remarkable intrinsic mechanisms by M. tuberculosis to counter most of the antibiotics. In addition, adaptive antibiotic resistance in M. tuberculosis is recently characterized mechanisms, which include biofilm-mediated resistance and formation of drug-tolerant persister cells and are responsible for relapse cases of infection. Biofilms are formed by a spectrum of pathogenic microorganisms, and provide a means for these organisms to guard themselves against antimicrobial agents. Bacterial biofilms are the basis of several diseases and mainly attributed to the increased antibiotic resistance unveiled by the microbial communities within the biofilm. The resistance in M. tuberculosis is multifactorial, there are several drug resistance mechanisms exist that act together in order to provide an increased level of resistance to biofilm communities. These mechanisms are based on wild type genes and are not the result of mutations. This chapter summarizes both historical and current scientific data in support of the known biofilm-based resistance and tolerance mechanisms in M. tuberculosis, that can further explore in clinical settings.