The potential impact of structural genomics on tuberculosis drug discovery

Mycobacterium tuberculosis, the causative agent of tuberculosis (TB) in humans, is a devastating infectious organism that kills approximately two million people annually. The current suite of antibiotics used to treat TB faces two main difficulties: (i) the emergence of multidrug-resistant (MDR) strains of M. tuberculosis, and (ii) the persistent state of the bacterium, which is less susceptible to antibiotics and causes very long antibiotic treatment regimes. The complete genome sequences of a laboratory strain (H37Rv) and a clinical strain (CDC1551) of M. tuberculosis and the concurrent identification of all the open reading frames that encode proteins within this organism, present structural biologists with a wide array of protein targets for structure determination. Comparative genomics of the species that make up the M. tuberculosis complex has also added an array of genomic information to our understanding of these organisms. In response to this, structural genomics consortia have been established for targeting proteins from M. tuberculosis. This review looks at the progress of these major initiatives and the potential impact of large scale structure determination efforts on the development of inhibitors to many proteins. Increasing sophistication in structure-based drug design approaches, in combination with increasing numbers of protein structures and inhibitors for TB proteins, will have a significant impact on the downstream development of TB antibiotics.