title: Exposure of Bacillus subtilis to low pressure (5 kilopascals) induces several global regulons, including those involved in the SigB-mediated general stress response.
abstract: Studies of how microorganisms respond to pressure have been limited mostly to the extreme high pressures of the deep sea (i.e., the piezosphere). In contrast, despite the fact that the growth of most bacteria is inhibited at pressures below ∼2.5 kPa, little is known of microbial responses to low pressure (LP). To study the global LP response, we performed transcription microarrays on Bacillus subtilis cells grown under normal atmospheric pressure (∼101 kPa) and a nearly inhibitory LP (5 kPa), equivalent to the pressure found at an altitude of ∼20 km. Microarray analysis revealed altered levels of 363 transcripts belonging to several global regulons (AbrB, CcpA, CodY, Fur, IolR, ResD, Rok, SigH, Spo0A). Notably, the highest number of upregulated genes, 86, belonged to the SigB-mediated general stress response (GSR) regulon. Upregulation of the GSR by LP was confirmed by monitoring the expression of the SigB-dependent ctc-lacZ reporter fusion. Measuring transcriptome changes resulting from exposure of bacterial cells to LP reveals insights into cellular processes that may respond to LP exposure.
authors.affiliation: Department of Microbiology and Cell Science, University of Florida, Merritt Island, Florida, USA.
authors.forename: Samantha M
authors.initials: SM
authors.lastname: Waters
authors.affiliation: Department of Microbiology and Cell Science, University of Florida, Merritt Island, Florida, USA.
authors.forename: José A
authors.initials: JA
authors.lastname: Robles-Martínez
authors.affiliation: Department of Microbiology and Cell Science, University of Florida, Merritt Island, Florida, USA WLN@ufl.edu.
authors.forename: Wayne L
authors.initials: WL
authors.lastname: Nicholson
mesh_terms: D001412:Bacillus subtilis / Q000737:chemistry* / Q000235:genetics* / Q000502:physiology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D009876:Operon; D011312:Pressure; D018085:Regulon; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*; D013312:Stress, Physiological
chemical_list: D001426:Bacterial Proteins; C079011:SigB protein, Bacteria; D012808:Sigma Factor