The role of thiol oxidative stress response in heat‐induced protein aggregate formation during thermotolerance in Bacillus subtilis. Issue 5 (29th January 2014)

• Record Type: Journal Article
• Authors: Runde, Stephanie; Molière, Noël; Heinz, Anja; Maisonneuve, Etienne; Janczikowski, Armgard; Elsholz, Alexander K. W.; Gerth, Ulf; Hecker, Michael; Turgay, Kürşad
• Is Part Of: Molecular microbiology. Volume 91:Issue 5(2014)
• Page Start: 1036
• Page End: 1052
• Publication Date: 2014-01-29
• Subjects: Molecular microbiology -- Periodicals; 572.829
• DOI: 10.1111/mmi.12521
• Languages: English
• ISSNs: 0950-382X

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p>Using <italic>B</italic><italic>acillus subtilis</italic> as a model organism, we investigated thermotolerance development by analysing cell survival and <italic>in vivo</italic> protein aggregate formation in severely heat‐shocked cells primed by a mild heat shock. We observed an increased survival during severe heat stress, accompanied by a strong reduction of heat‐induced cellular protein aggregates in cells lacking the ClpXP protease. We could demonstrate that the transcription factor Spx, a regulatory substrate of ClpXP, is critical for the prevention of protein aggregate formation because its regulon encodes redox chaperones, such as thioredoxin, required for protection against thiol‐specific oxidative stress. Consequently <italic>B</italic><italic>. subtilis</italic> cells grown in the absence of oxygen were more protected against severe heat shock and much less protein aggregates were detected compared to aerobically grown cells. The presented results indicate that in <italic>B</italic><italic>. subtilis</italic> Spx and its regulon plays not only an important role for oxidative but also for heat stress response and thermotolerance development. In addition, our experiments suggest that the protection of misfolded proteins from thiol oxidation during heat shock can be critical for the prevention of cellular protein aggregation <italic>in vivo</italic>.</p> </abstract>