ABSTRACT
Tuberculosis (TB) has been a leading cause of death throughout human history. The World Health Organization reported over 1.6 million deaths from TB and over 10 million new cases of TB in 2017, making TB the single leading cause of death from an infectious agent today. The chemical structure of the genome of M. tuberculosis is remarkably uniform with a high guanine + cytosine content throughout, indicating that it has evolved with minimal incorporation of DNA from extraneous sources. The mycobacterial genome is also unique in containing a large number of genes, up to 10% of the total coding potential, that code for unrelated families, Pro-Glu and Pro-Pro-Glu, of acidic, glycine-rich proteins that contribute to the diversity in antigenic structure, virulence. The characteristic slow growth of Mycobacterium. tuberculosis and its virulence have slowed down its research. However, the ability to perform gene transfer in M. tuberculosis mycobacteria has provided many new ways to understand the tubercle bacillus and its biology.
