CarD Tricks and Magic Spots: Mechanisms of Stringent Control in Mycobacteria

Department of Microbiology and Immunology, Program in Microbial Pathogenesis and Host Defense, University of California, San Francisco, San Francisco, CA 94143, USA.
Cell host & microbe (Impact Factor: 12.33). 08/2009; 6(1):1-2. DOI: 10.1016/j.chom.2009.07.001
Source: PubMed


Tuberculosis (TB) continues to be a major global health problem, with 8.9 million new cases and 1.7 million deaths per year (Dye, 2006). A hallmark of Mycobacterium tuberculosis pathogenesis is the ability of bacilli to enter a slow-growing or nonreplicative state, leading to a latent infection lasting the lifetime of the host. Lack of vital nutrients, oxygen, and iron is thought to restrict bacterial replication during infection (Boshoff and Barry, 2005). For example, M. tuberculosis bacilli have the exceptional ability to persist for decades in vitro under starvation conditions and can revive upon addition of nutrients. This remarkable ability of M. tuberculosis to persist in the face of nutritional and immune stresses renders tuberculosis difficult to treat with current antibiotics, which generally require some bacterial growth to exert their killing effects. Thus, elucidating the mechanisms of persistence is of great interest in the field and critically important to the global control of this deadly disease.

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Available from: Lynn Connolly, Aug 04, 2014
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    • "The interaction with RNAP implicates CdnL in a possibly vital role in M. xanthus transcription. The CdnL homolog in mycobacteria, also essential, was recently implicated in the control of rRNA transcription at steady state and during diverse cellular stresses such as starvation, in the early stages of which there is as much as a 20-fold enhancement in cdnL expression (18,33). This CdnL was also shown to bind RNAP, but its mapping to the β subunit was deduced from observations with TtCdnL, since mycobacterial CdnL itself failed to exhibit such an interaction in the two-hybrid analysis employed. "
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