title: Evaluating the role of phage-shock protein A in Burkholderia pseudomallei.
abstract: The phage-shock protein (Psp) response is an extracytoplasmic response system that is vital for maintenance of the cytoplasmic membrane when the cell encounters stressful conditions. The paradigm of the Psp response has been established in Escherichia coli. The response has been shown to be important for survival during the stationary phase, maintenance of the proton motive force across membranes and implicated in virulence. In this study, we identified a putative PspA homologue in Burkholderia pseudomallei, annotated as BPSL2105. Similar to the induction of PspA in E. coli, the expression of B. pseudomallei BPSL2105 was induced by heat shock. Deletion of BPSL2105 resulted in a survival defect in the late stationary phase coincident with dramatic changes in the pH of the culture medium. The B. pseudomallei BPSL2105 deletion mutant also displayed reduced survival in macrophage infection - the first indication that the Psp response plays a role during intracellular pathogenesis in this species. The purified protein formed large oligomeric structures similar to those observed for the PspA protein of E. coli, and PspA homologues in Bacillus, cyanobacteria and higher plants, providing further evidence to support the identification of BPSL2105 as a PspA-like protein in B. pseudomallei.
authors.affiliation: 1​Biomedical Sciences, Defence Science and Technology Laboratory, Porton Down, Salisbury, UK.
authors.forename: Stephanie J
authors.initials: SJ
authors.lastname: Southern
authors.affiliation: 2​Department of Chemistry, University of Southampton, Southampton, UK.
authors.forename: Abigail
authors.initials: A
authors.lastname: Male
authors.affiliation: 1​Biomedical Sciences, Defence Science and Technology Laboratory, Porton Down, Salisbury, UK.
authors.forename: Timothy
authors.initials: T
authors.lastname: Milne
authors.affiliation: 1​Biomedical Sciences, Defence Science and Technology Laboratory, Porton Down, Salisbury, UK 3​University of Western Australia, QEII Medical Centre, Nedlands, Western Australia, Australia.
authors.forename: Mitali
authors.initials: M
authors.lastname: Sarkar-Tyson
authors.affiliation: 2​Department of Chemistry, University of Southampton, Southampton, UK 4​The Institute for Life Sciences, University of Southampton, Southampton, UK.
authors.forename: Ali
authors.initials: A
authors.lastname: Tavassoli
authors.affiliation: 1​Biomedical Sciences, Defence Science and Technology Laboratory, Porton Down, Salisbury, UK.
authors.forename: Petra C F
authors.initials: PC
authors.lastname: Oyston
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D016957:Burkholderia pseudomallei / Q000235:genetics / Q000502:physiology* / Q000528:radiation effects; D003470:Culture Media / Q000737:chemistry; D017353:Gene Deletion; D020869:Gene Expression Profiling; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008264:Macrophages / Q000276:immunology / Q000382:microbiology; D050296:Microbial Viability / Q000528:radiation effects; D055503:Protein Multimerization; D013312:Stress, Physiological
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D006360:Heat-Shock Proteins; C069816:phage shock protein, Bacteria