Periplasmic peptidyl-prolyl isomerases SurA and FkpA play an important role in the starvation-stress response (SSR) of Salmonella enterica serovar Typhimurium

Kenyon, W.J., Humphreys, S., Roberts, M. and Spector, M.P. (2010) Periplasmic peptidyl-prolyl isomerases SurA and FkpA play an important role in the starvation-stress response (SSR) of Salmonella enterica serovar Typhimurium. Antonie van Leeuwenhoek, 98(1), pp. 51-63. (doi: 10.1007/s10482-010-9428-2)

Abstract

Carbon-energy source (C)-starved cells of Salmonella enterica serovar Typhimurium (S. Typhimurium) are remarkably more resistant to stress than actively growing ones. Carbon-starved S. Typhimurium is capable of withstanding extended periods of starvation and assault from a number of different stresses that rapidly kill growing cells. These unique properties of the C-starved cell are the direct result of a series of genetic and physiological adaptations referred to as the starvation-stress response (SSR). Previous work established that the SSR of S. Typhimurium is partially regulated by the extracytoplasmic function sigma factor σE. As part of an effort to identify σE-regulated SSR genes, we investigated surA and fkpA, encoding two different classes of peptidyl-prolyl isomerase that function in folding cell envelope proteins. Both surA and fkpA are members of the heat-shock-inducible σE regulon of Escherichia coli. Although both genes are expressed in C-starved Salmonella cells, evidence indicates that surA and fkpA are not C-starvation-inducible. Furthermore, their expression during C-starvation does not appear to be σE-dependent. Nonetheless, surA and fkpA proved to be important, to differing degrees, for long-term C-starvation survival and for the cross-resistance of C-starved cells to high temperature, acidic pH, and the antimicrobial peptide polymyxin B, but neither were required for cross-resistance to oxidative stress. These results point to fundamental differences between heat-shock-inducible and C-starvation-inducible genes regulated by σE and suggest that genes other than surA and fkpA are involved in the σE-regulated branch of the SSR in Salmonella.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Roberts, Professor Mark
• Authors: Kenyon, W.J., Humphreys, S., Roberts, M., and Spector, M.P.
• Subjects: Q Science > QR Microbiology
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Antonie van Leeuwenhoek
• Publisher: 0003-6072
• ISSN (Online): 1572-9699
• Published Online: 16 March 2010