The Burkholderia pseudomallei RpoE (AlgU) operon is involved in environmental stress tolerance and biofilm formation.
Burkholderia pseudomallei, the causative agent of melioidosis, can be isolated from soil and water. To persist, adapt and survive within and outside their human host, bacteria rely on regulatory mechanisms that allow them to respond rapidly to stressful situations. We have examined the possible role of B. pseudomallei alternative sigma factor sigma(E) (RpoE) in the stress response and found that rpoE and its putative regulators (bprE-rseB-mucD) are transcribed in a single transcriptional unit. Inactivation of the rpoE operon changed the B. pseudomallei phenotype. Changes included increased susceptibility to killing by menadione and H(2)O(2), susceptibility to high osmolarity, reduced ability to form biofilms, and reduced survival in macrophage J774A.1. Therefore, we conclude that rpoE controls gene expression that contributes, at least in part, to B. pseudomallei adaptation to adverse environmental conditions.
Korbsrisate
Sunee
S
Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand. grsks@mahidol.ac.th
Vanaporn
Muthita
M
Kerdsuk
Phansupa
P
Kespichayawattana
Wannapa
W
Vattanaviboon
Paiboon
P
Kiatpapan
Pornpimon
P
Lertmemongkolchai
Ganjana
G
D000222:Adaptation, Physiological; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D018441:Biofilms / Q000254:growth & development*; D016957:Burkholderia pseudomallei / Q000235:genetics / Q000502:physiology*; D002460:Cell Line; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D005809:Genes, Regulator; D008264:Macrophages / Q000382:microbiology; D051379:Mice; D008854:Microscopy, Electron; D016254:Mutagenesis, Insertional; D009876:Operon; D009997:Osmotic Pressure; D016877:Oxidants / Q000633:toxicity; D018384:Oxidative Stress; D012329:RNA, Bacterial / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012808:Sigma Factor / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D016877:Oxidants; D012329:RNA, Bacterial; D012333:RNA, Messenger; D012808:Sigma Factor; D014157:Transcription Factors; C063202:sporulation-specific sigma factors