Novel inducers of the envelope stress response BaeSR in Salmonella Typhimurium: BaeR is critically required for tungstate waste disposal

• Published in: PloS one Vol. 6; no. 8; p. e23713
• Main Authors: Appia-Ayme, Corinne, Patrick, Elaine, Sullivan, Matthew J, Alston, Mark J, Field, Sarah J, AbuOun, Manal, Anjum, Muna F, Rowley, Gary
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 23.08.2011; Public Library of Science (PLoS)
• Subjects: Animals; Antibiotics; Bacterial Outer Membrane Proteins; Biology; Calves; Cell division; Cellular stress response; Chickens; Cloning; Drug Resistance - genetics; E coli; Escherichia coli; Gene Expression Regulation, Bacterial; Genes; Health aspects; Infection; Infections; Iron; Kinases; Laboratories; Medicine; Mice; Multidrug Resistance-Associated Proteins - physiology; Nodulation; Phosphorylation; Physiology; Poultry; Protein Kinases - physiology; Proteins; Pseudomonas syringae; Salmonella; Salmonella Typhimurium; Salmonella typhimurium - genetics; Salmonella typhimurium - physiology; Sodium; Sodium tungstate; Soil water; Stationary phase; Stress response; Stress, Physiological; Stresses; Survival; Tungsten compounds; Tungsten Compounds - metabolism; Typhoid; Waste disposal; Waste management; United Kingdom > UK
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0023713

The RpoE and CpxR regulated envelope stress responses are extremely important for Salmonella Typhimurium to cause infection in a range of hosts. Until now the role for BaeSR in both the Salmonella Typhimurium response to stress and its contribution to infection have not been fully elucidated. Here we demonstrate stationary phase growth, iron and sodium tungstate as novel inducers of the BaeRregulon, with BaeR critically required for Salmonella resistance to sodium tungstate. We show that functional overlap between the resistance nodulation-cell division (RND) multidrug transporters, MdtA, AcrD and AcrB exists for the waste disposal of tungstate from the cell. We also point to a role for enterobactinsiderophores in the protection of enteric organisms from tungstate, akin to the scenario in nitrogen fixing bacteria. Surprisingly, BaeR is the first envelope stress response pathway investigated in S. Typhimurium that is not required for murine typhoid in either ity(S) or ity(R) mouse backgrounds. BaeR is therefore either required for survival in larger mammals such as pigs or calves, an avian host such as chickens, or survival out with the host altogether where Salmonella and related enterics must survive in soil and water.