Phosphosignaling controls Mycobacterium tuberculosis (Mtb) physiology and pathogenesis on every level. In addition to two-component systems that phosphorylate protein on His and Asp, Mtb also produces eleven Ser/Thr kinases (STPKs). These STPKs are central for bacterial adaptations, and two Mtb STPKs, PknA and PknB, are essential for growth and under development as drug targets. The eleven STPKs were identified in the 1998 Mtb genome sequence, and no new STPKs have been described since. In a functional proteomics screen of Mtb ATPases, we identified >80 hypothetical proteins as novel, previously unrecognized ATPases. Further characterization showed remote structural homology of one of the hypotheticals, Rv0647c, with non- typical STPKs. Given the ATPase activity of Rv0647c, we tested for STPK activity and found that Rv0647c is a novel, highly divergent STPK. Importantly, Rv0647c is predicted to be essential, suggesting that Rv0647c has central functions relating to Mtb growth. Here, we will test the hypothesis that Rv0647c is a growth regulator kinase in Mtb by testing Rv0647c's essentiality, identifying cellular substrates, and by solving the Rv0647c crystal structure. Together, this project identifies a new component of the Mtb phosphosignaling network and provides the basis for targeting this member of a highly druggable enzyme family.

Public Health Relevance

Tuberculosis (TB) has a massive impact on public health. This project aims to elucidate the role of a new Mtb phosphosignaling enzyme, a protein kinase. This project will provide insight into the kinase's physiologic role and potential as a new drug target.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21AI121829-01
Application #
9016364
Study Section
Prokaryotic Cell and Molecular Biology Study Section (PCMB)
Program Officer
Kraigsley, Alison
Project Start
2016-01-01
Project End
2017-12-31
Budget Start
2016-01-01
Budget End
2016-12-31
Support Year
1
Fiscal Year
2016
Total Cost
$299,187
Indirect Cost
$140,887
Name
Seattle Biomedical Research Institute
Department
Type
DUNS #
070967955
City
Seattle
State
WA
Country
United States
Zip Code
98109