Toggle Main Menu Toggle Search

Open Access padlockePrints

The FtsH protease is involved in development, stress response and heat shock control in Caulobacter crescentus

Lookup NU author(s): Dr Phillip AldridgeORCiD

Downloads

Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Abstract

The ftsH gene of Caulobacter crescentus has been isolated and identified as a component of the general stress response of this organism. In C. crescentus, ftsH expression is transiently induced after temperature upshift and in stationary phase. Consistent with this, mutants deprived of the FtsH protease are viable at normal growth conditions, but are highly sensitive to elevated temperature, increased salt concentration or the presence of antibiotics. Overexpression of ftsH resulted in an increased salt but not thermotolerance, emphasizing the importance of the FtsH protease in stress response. Mutants lacking FtsH were unable to undergo morphological and physiological adaptation in stationary phase and, upon starvation, experienced a more pronounced loss of viability than cells containing FtsH. In addition, cells lacking FtsH had an increased cellular concentration of the heat shock sigma factor sigma32, indicating that, as in Escherichia coli, the FtsH protease is involved in the control of the C. crescentus heat shock response. In agreement with this, transcription of the heat-induced sigma32-dependent gene dnaK was derepressed at normal temperature when FtsH was absent. In contrast, the groEL gene, which is controlled in response to heat stress by both sigma32 and a HcrA/CIRCE mechanism, was not derepressed in an ftsH mutant. Finally, FtsH is involved in C. crescentus development and cell cycle control. ftsH mutants were unable to synthesize stalks efficiently and had a severe cell division phenotype. In the absence of FtsH, swarmer cells differentiated into stalked cells faster than when FtsH was present, even though the entire cell cycle was longer under these conditions. Thus, directly or indirectly, the FtsH protease is involved in the inherent biological clock mechanism, which controls the timing of cell differentiation in C. crescentus.


Publication metadata

Author(s): Aldridge P; Fischer B; Rummel G; Jenal U

Publication type: Article

Publication status: Published

Journal: Molecular Microbiology

Year: 2002

Volume: 44

Issue: 2

Pages: 461-478

ISSN (print): 0950-382X

ISSN (electronic): 1365-2958

Publisher: Wiley-Blackwell Publishing Ltd.

URL: http://dx.doi.org/10.1046/j.1365-2958.2002.02887.x

DOI: 10.1046/j.1365-2958.2002.02887.x


Altmetrics

Altmetrics provided by Altmetric


Share