Premium
Temperature effect on inclusion body formation and stress response in the periplasm of Escherichia coli
Author(s) -
Hunke Sabine,
Betton JeanMichel
Publication year - 2003
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1046/j.1365-2958.2003.03785.x
Subject(s) - periplasmic space , biology , escherichia coli , mutant , heat shock , inclusion bodies , heat shock protein , microbiology and biotechnology , protein folding , biochemistry , enterobacteriaceae , gene
Summary We previously characterized a defective‐folding mutant of maltose‐binding protein of Escherichia coli , MalE31, which formed periplasmic inclusion bodies. Here, we show that MalE31 aggregation does not affect bacterial growth at 30°C but is lethal at 37°C. Surprisingly, under mild heat shock conditions at 42°C, inclusion bodies are degraded and bacterial growth is restored. One physiological consequence for the cells overproducing MalE31 was to induce an extracytoplasmic stress response by increasing the expression of the heat shock protease DegP via the CpxA/CpxR two‐component signalling pathway. Furthermore, we show that the Cpx response is required to rescue the cells from the toxicity mediated by MalE31. Finally, expression of highly destabilized MalE variants that do not aggregate in the periplasm also induces the Cpx pathway, indicating that inclusion body formation is not necessary to activate this specific extracytoplasmic stress regulatory system.