Target Mechanism-Based Whole-Cell Screening Identifies Bortezomib as an Inhibitor of Caseinolytic Protease in Mycobacteria

Target Mechanism-Based Whole-Cell Screening Identifies Bortezomib as an Inhibitor of Caseinolytic Protease in Mycobacteria
Title:
Target Mechanism-Based Whole-Cell Screening Identifies Bortezomib as an Inhibitor of Caseinolytic Protease in Mycobacteria
Other Titles:
mBio
DOI:
10.1128/mBio.00253-15
Publication Date:
05 May 2015
Citation:
Target Mechanism-Based Whole-Cell Screening Identifies Bortezomib as an Inhibitor of Caseinolytic Protease in Mycobacteria Wilfried Moreira, Grace J. Y. Ngan, Jian Liang Low, Anders Poulsen, Brian C. S. Chia, Melgious J. Y. Ang, Amelia Yap, Justina Fulwood, Umayal Lakshmanan, Jolander Lim, Audrey Y. T. Khoo, Horst Flotow, Jeffrey Hill, Ravikiran M. Raju, Eric J. Rubin, and Thomas Dick 6:3 e00253-15; Published 5 May 2015, doi:10.1128/mBio.00253-15
Abstract:
A novel type of antibacterial screening method, a target mechanism-based whole-cell screening method, was developed to combine the advantages of target mechanism- and whole-cell-based approaches. A mycobacterial reporter strain with a synthetic phenotype for caseinolytic protease (ClpP1P2) activity was engineered, allowing the detection of inhibitors of this enzyme inside intact bacilli. A high-throughput screening method identified bortezomib, a human 26S proteasome drug, as a potent inhibitor of ClpP1P2 activity and bacterial growth. A battery of secondary assays was employed to demonstrate that bortezomib indeed exerts its antimicrobial activity via inhibition of ClpP1P2: Down- or upmodulation of the intracellular protease level resulted in hyper- or hyposensitivity of the bacteria, the drug showed specific potentiation of translation error-inducing aminoglycosides, ClpP1P2-specific substrate WhiB1 accumulated upon exposure, and growth inhibition potencies of bortezomib derivatives correlated with ClpP1P2 inhibition potencies. Furthermore, molecular modeling showed that the drug can bind to the catalytic sites of ClpP1P2. This work demonstrates the feasibility of target mechanism-based whole-cell screening, provides chemical validation of ClpP1P2 as a target, and identifies a drug in clinical use as a new lead compound for tuberculosis therapy.
License type:
http://creativecommons.org/licenses/by-nc-sa/4.0/
Funding Info:
Singapore Ministry of Health, National Medical Research Council, (NMRC/CBRG/0022/2012), National Medical Research Council, center grant MINE, Research Core no. 4 (NMRC/CG/013/2013), Agency for Science, Technology and Research (A*STAR)
Description:
ISSN:
2150-7511
Files uploaded:

File Size Format Action
moreira-mbio-2015-tuber-tb-bortezomib.pdf 2.26 MB PDF Open