Article

The ins and outs of Mycobacterium tuberculosis protein export.

Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, CB #7290, Chapel Hill, NC 27599, USA.
Tuberculosis (Edinburgh, Scotland) (impact factor: 2.54). 12/2011; 92(2):121-32. DOI:10.1016/j.tube.2011.11.005 pp.121-32
Source: PubMed

ABSTRACT Mycobacterium tuberculosis is an important pathogen that infects approximately one-third of the world's population and kills almost two million people annually. An important aspect of M. tuberculosis physiology and pathogenesis is its ability to export proteins into and across the thick mycobacterial cell envelope, where they are ideally positioned to interact with the host. In addition to the specific proteins that are exported by M. tuberculosis, the systems through which these proteins are exported represent potential targets for future drug development. M. tuberculosis possesses two well-known and conserved export systems: the housekeeping Sec pathway and the Tat pathway. In addition, M. tuberculosis possesses specialized export systems including the accessory SecA2 pathway and five ESX pathways. Here we review the current understanding of each of these export systems, with a focus on M. tuberculosis, and discuss the contribution of each system to disease and physiology.

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Keywords

accessory SecA2 pathway
 
current understanding
 
ESX pathways
 
export proteins
 
future drug development
 
interact
 
M. tuberculosis
 
M. tuberculosis physiology
 
M. tuberculosis possesses specialized export systems
 
Mycobacterium tuberculosis
 
pathogen
 
pathogenesis
 
potential targets
 
proteins
 
specific proteins
 
thick mycobacterial cell envelope
 
world's population