Multidrug-resistant (MOR) tuberculosis (TB) is recognized as an emerging infectious disease and a major problem in global public health. MDR 44. tuberculosis is also classified as a Category C Priority Pathogen for biodefense research. The threat of MDR and extensively/extremely drug-resistant (XDR) TB outbreaks that are resistant to current anti-TB drugs, either due to natural emergence or bioterrorism, is an alarming scenario since untreated (or untreatable) TB carries a mortality rate of 40-60%. Public health preparedness for intractable TB cases requires the development of new chemotherapies that kill M. tuberculosis or impair its virulence or growth in the host. To this end, studies on M. tuberculosis biology are priorities of utmost importance as they may illuminate avenues to develop new chemotherapies. The long-term goal of this project is to elucidate the biosynthesis of mycobacterial siderophores (iron-scavenging compounds) that are required for multiplication of M. tuberculosis inside the macrophages of the host, an ability of (0. tuberculosis needed to produ?e disease. We will pursue this goal through two specific aims: (1) To probe in vitro the enzymatic functions of the MbtABCDEF enzyme system in siderophore biosynthesis;and (2) To investigate the involvement of the genes in the mbt gene cluster in siderophore production using a genetic approach. These two aims are highly complementary, yet independent, and represent biochemical and genetic approaches, respectively, to study the biosynthesis of mycobacterial siderophores. The knowledge gained will shed light on unexplored aspects of mycobacterial siderophore biosynthesis. This project will revealed potential new targets for anti-tuberculosis drug development and thus it may illuminate novel avenues for developing drugs that may find a particularly important niche in therapeutic and/or prophylactic multi-drug treatments against MDRIXDR M. tuberculosis, which is a major threat to global public health and a potential agent for use in bioterrorism.

Public Health Relevance

The knowledge gained with the proposed studies will shed light on unexplored aspects of mycobacterial siderophore biosynthesis. This project will reveal potential new target candidates for anti-tuberculosis drug development, and thus it may illuminate novel avenues for developing drugs that may find a particularly important niche in therapeutic and/or prophylactic multi drug treatments against multidrug resistant and extensively drug-resistant Mycobacterium tuberculosis, which is a major threat to global public health and a potential agent for use in bioterrorism.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
1R01AI075092-01A1
Application #
7467066
Study Section
Bacterial Pathogenesis Study Section (BACP)
Program Officer
Lacourciere, Karen A
Project Start
2009-05-08
Project End
2010-01-31
Budget Start
2009-05-08
Budget End
2010-01-31
Support Year
1
Fiscal Year
2009
Total Cost
$344,724
Indirect Cost
Name
Weill Medical College of Cornell University
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
060217502
City
New York
State
NY
Country
United States
Zip Code
10065
Lun, Shichun; Guo, Haidan; Adamson, John et al. (2013) Pharmacokinetic and in vivo efficacy studies of the mycobactin biosynthesis inhibitor salicyl-AMS in mice. Antimicrob Agents Chemother 57:5138-40
Tatham, Elizabeth; Sundaram Chavadi, Sivagami; Mohandas, Poornima et al. (2012) Production of mycobacterial cell wall glycopeptidolipids requires a member of the MbtH-like protein family. BMC Microbiol 12:118
Ferreras, Julian A; Gupta, Akash; Amin, Neal D et al. (2011) Chemical scaffolds with structural similarities to siderophores of nonribosomal peptide-polyketide origin as novel antimicrobials against Mycobacterium tuberculosis and Yersinia pestis. Bioorg Med Chem Lett 21:6533-7
Chavadi, Sivagami Sundaram; Stirrett, Karen L; Edupuganti, Uthamaphani R et al. (2011) Mutational and phylogenetic analyses of the mycobacterial mbt gene cluster. J Bacteriol 193:5905-13