# $$Mycobacterium$$ $$tuberculosis$$ ClpP1 and ClpP2 Function Together in Protein Degradation and are Required for Viability $$in$$ $$vitro$$ and During Infection

 Title: $$Mycobacterium$$ $$tuberculosis$$ ClpP1 and ClpP2 Function Together in Protein Degradation and are Required for Viability $$in$$ $$vitro$$ and During Infection Author: Unnikrishnan, Meera; Krishnamoorthy, Vidhya; Raju, Ravikiran M.; Rubin, Daniel H. F.; Kandror, Olga; Akopian, Tatos; Goldberg, Alfred L.; Rubin, Eric Joseph Note: Order does not necessarily reflect citation order of authors. Citation: Raju, Ravikiran M., Meera Unnikrishnan, Daniel H. F. Rubin, Vidhya Krishnamoorthy, Olga Kandror, Tatos N. Akopian, Alfred L. Goldberg, and Eric J. Rubin. 2012. Mycobacterium tuberculosis ClpP1 and ClpP2 function together in protein degradation and are required for viability in vitro and during infection. PLoS Pathogens 8(2): e1002511. Full Text & Related Files: 3280978.pdf (885.4Kb; PDF) Abstract: In most bacteria, Clp protease is a conserved, non-essential serine protease that regulates the response to various stresses. Mycobacteria, including $$Mycobacterium$$ $$tuberculosis$$ (Mtb) and $$Mycobacterium$$ $$smegmatis$$, unlike most well studied prokaryotes, encode two ClpP homologs, ClpP1 and ClpP2, in a single operon. Here we demonstrate that the two proteins form a mixed complex (ClpP1P2) in mycobacteria. Using two different approaches, promoter replacement, and a novel system of inducible protein degradation, leading to inducible expression of $$clpP1$$ and $$clpP2$$, we demonstrate that both genes are essential for growth and that a marked depletion of either one results in rapid bacterial death. ClpP1P2 protease appears important in degrading missense and prematurely terminated peptides, as partial depletion of ClpP2 reduced growth specifically in the presence of antibiotics that increase errors in translation. We further show that the ClpP1P2 protease is required for the degradation of proteins tagged with the SsrA motif, a tag co-translationally added to incomplete protein products. Using active site mutants of ClpP1 and ClpP2, we show that the activity of each subunit is required for proteolysis, for normal growth of Mtb $$in$$ $$vitro$$ and during infection of mice. These observations suggest that the Clp protease plays an unusual and essential role in Mtb and may serve as an ideal target for antimycobacterial therapy. Published Version: doi:10.1371/journal.ppat.1002511 Other Sources: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3280978/pdf/ Terms of Use: This article is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#LAA Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:9368031 Downloads of this work: