RT Journal Article SR Electronic(1) A1 Estorninho, Megan A1 Smith, Hilde A1 Thole, Jelle A1 Harders-Westerveen, Jose A1 Kierzek, Andrzej A1 Butler, Rachel E. A1 Neyrolles, Olivier A1 Stewart, Graham R.YR 2010 T1 ClgR regulation of chaperone and protease systems is essential for Mycobacterium tuberculosis parasitism of the macrophage JF Microbiology, VO 156 IS 11 SP 3445 OP 3455 DO https://doi.org/10.1099/mic.0.042275-0 PB Microbiology Society, SN 1465-2080, AB Chaperone and protease systems play essential roles in cellular homeostasis and have vital functions in controlling the abundance of specific cellular proteins involved in processes such as transcription, replication, metabolism and virulence. Bacteria have evolved accurate regulatory systems to control the expression and function of chaperones and potentially destructive proteases. Here, we have used a combination of transcriptomics, proteomics and targeted mutagenesis to reveal that the clp gene regulator (ClgR) of Mycobacterium tuberculosis activates the transcription of at least ten genes, including four that encode protease systems (ClpP1/C, ClpP2/C, PtrB and HtrA-like protease Rv1043c) and three that encode chaperones (Acr2, ClpB and the chaperonin Rv3269). Thus, M. tuberculosis ClgR controls a larger network of protein homeostatic and regulatory systems than ClgR in any other bacterium studied to date. We demonstrate that ClgR-regulated transcriptional activation of these systems is essential for M. tuberculosis to replicate in macrophages. Furthermore, we observe that this defect is manifest early in infection, as M. tuberculosis lacking ClgR is deficient in the ability to control phagosome pH 1 h post-phagocytosis., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.042275-0