Comparative transcriptome and phenotype analysis of acid-stressed Bacillus cereus strains
Ontology highlight
ABSTRACT:
ORGANISM(S): Bacillus cereus ATCC 10987 Bacillus cereus ATCC 14579 Bacillus cereus
PROVIDER: GSE13773 | GEO | 2009/11/25
SECONDARY ACCESSION(S): PRJNA110781
REPOSITORIES: GEO
Similar Datasets
Project description:This SuperSeries is composed of the following subset Series: GSE13711: Comparative transcriptome and phenotype analysis of acid-stressed Bacillus cereus strain ATCC 14579 GSE13729: Comparative transcriptome and phenotype analysis of acid-stressed Bacillus cereus strain ATCC 10987 Refer to individual Series
2010-06-25 | E-GEOD-13773 | biostudies-arrayexpress
Project description:The food-borne human pathogen Bacillus cereus is found in environments that often have a low pH, such as food and soil. The physiological response upon exposure to several levels of acidity were investigated of B. cereus model strain ATCC 10987, to elucidate the response of B. cereus to acid stress. pH 5.4, pH 5.0, pH 4.8 and pH 4.5 were selected to conduct microarray analyses, based on the differences in physiological response upon exposure to the acid conditions. The transcriptome data revealed response specific profiles. Showing mechanisms induced upon all the different acid down-shocks, such as nitrate reductase and energy production genes, and several genes specifically expressed differentially in mild or lethal levels of acidity, such as F1F0-ATPase and cydAB. Furthermore, mechanisms involved in oxidative stress response were found highly up-regulated in response to both mild and lethal acid stress. The induction of oxidative stress related genes may be a response to the formation of reactive oxygen species by a perturbation of the electron transport chain. Therefore, the formation of hydroxyl radicals and/ or peroxynitrite was monitored upon exposure to the different levels of acidity with a fluorescent probe in a flow cytometer. The formation of these oxidative compounds was shown to be specific for lethal pHs and a model to relate radical formation with the observed transcriptome profiles was proposed.
2009-11-25 | GSE13729 | GEO
Project description:The food-borne human pathogen Bacillus cereus is found in environments that often have a low pH, such as food and soil. The physiological response upon exposure to several levels of acidity were investigated of B. cereus model strain ATCC 14579, to elucidate the response of B. cereus to acid stress. pH 5.4, pH 5.0, pH 4.8 and pH 4.5 were selected to conduct microarray analyses, based on the differences in physiological response upon exposure to the acid conditions. The transcriptome data revealed response specific profiles. Showing mechanisms induced upon all the different acid down-shocks, such as nitrate reductase and energy production genes, and several genes specifically expressed differentially in mild or lethal levels of acidity, such as F1F0-ATPase and cydAB. Furthermore, mechanisms involved in oxidative stress response were found highly up-regulated in response to both mild and lethal acid stress. The induction of oxidative stress related genes may be a response to the formation of reactive oxygen species by a perturbation of the electron transport chain. Therefore, the formation of hydroxyl radicals and/ or peroxynitrite was monitored upon exposure to the different levels of acidity with a fluorescent probe in a flow cytometer. The formation of these oxidative compounds was shown to be specific for lethal pHs and a model to relate radical formation with the observed transcriptome profiles was proposed.
2009-11-25 | GSE13711 | GEO
Project description:The food-borne human pathogen Bacillus cereus is found in environments that often have a low pH, such as food and soil. The physiological response upon exposure to several levels of acidity were investigated of B. cereus model strain ATCC 14579, to elucidate the response of B. cereus to acid stress. pH 5.4, pH 5.0, pH 4.8 and pH 4.5 were selected to conduct microarray analyses, based on the differences in physiological response upon exposure to the acid conditions. The transcriptome data revealed response specific profiles. Showing mechanisms induced upon all the different acid down-shocks, such as nitrate reductase and energy production genes, and several genes specifically expressed differentially in mild or lethal levels of acidity, such as F1F0-ATPase and cydAB. Furthermore, mechanisms involved in oxidative stress response were found highly up-regulated in response to both mild and lethal acid stress. The induction of oxidative stress related genes may be a response to the formation of reactive oxygen species by a perturbation of the electron transport chain. Therefore, the formation of hydroxyl radicals and/ or peroxynitrite was monitored upon exposure to the different levels of acidity with a fluorescent probe in a flow cytometer. The formation of these oxidative compounds was shown to be specific for lethal pHs and a model to relate radical formation with the observed transcriptome profiles was proposed. Per acid down-shock three exposure times (i.e., 10, 30 and 60 min) were each compared with non-exposed cells (i.e., t0). In total 4 different acid down-shocks were applied, pH 5.4, pH 5.0, pH 4.8 and pH 4.5. The experiments were performed in duplicate and the duplicate samples were hybridised with a dye-swap.
2010-06-25 | E-GEOD-13711 | biostudies-arrayexpress
Project description:The food-borne human pathogen Bacillus cereus is found in environments that often have a low pH, such as food and soil. The physiological response upon exposure to several levels of acidity were investigated of B. cereus model strain ATCC 10987, to elucidate the response of B. cereus to acid stress. pH 5.4, pH 5.0, pH 4.8 and pH 4.5 were selected to conduct microarray analyses, based on the differences in physiological response upon exposure to the acid conditions. The transcriptome data revealed response specific profiles. Showing mechanisms induced upon all the different acid down-shocks, such as nitrate reductase and energy production genes, and several genes specifically expressed differentially in mild or lethal levels of acidity, such as F1F0-ATPase and cydAB. Furthermore, mechanisms involved in oxidative stress response were found highly up-regulated in response to both mild and lethal acid stress. The induction of oxidative stress related genes may be a response to the formation of reactive oxygen species by a perturbation of the electron transport chain. Therefore, the formation of hydroxyl radicals and/ or peroxynitrite was monitored upon exposure to the different levels of acidity with a fluorescent probe in a flow cytometer. The formation of these oxidative compounds was shown to be specific for lethal pHs and a model to relate radical formation with the observed transcriptome profiles was proposed. Per acid down-shock three exposure times (i.e., 10, 30 and 60 min) were each compared with non-exposed cells (i.e., t0). In total 4 different acid down-shocks were applied, pH 5.4, pH 5.0, pH 4.8 and pH 4.5. The experiments were performed in duplicate and the duplicate samples were hybridised with a dye-swap.
2010-06-25 | E-GEOD-13729 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below.
2015-10-10 | GSE24635 | GEO
Project description:Antimicrobial chemicals are widely applied to clean and disinfect food-contacting surfaces. However, the cellular response of bacteria, such as Bacillus cereus, to various disinfectants is unclear. In this study, the physiological and genome-wide transcriptional responses of B. cereus ATCC 14579 exposed to four different disinfectants (i.e., benzalkonium chloride, sodium hypochlorite, hydrogen peroxide, and peracetic acid) were analyzed. The physiological response of B. cereus to different concentrations of the disinfectants used was investigated. For each disinfectant, concentrations leading to the attenuation of growth, growth arrest, and cell death were studied in more detail. The simultaneous analysis of the transcriptional responses of B. cereus upon exposure to the different concentrations of disinfectants revealed common responses induced by the four disinfectants. Notably, genes involved in the general and oxidative stress responses were commonly up-regulated. Furthermore, the obtained results indicate that all the disinfectants also induce specific responses. Exposure to benzalkonium chloride, a disinfectant known to induce membrane damage, specifically induced genes involved in the fatty acid metabolism. Benzalkonium chloride induced-membrane damage was confirmed by fluorescence microscopy and fatty acid analysis confirmed that fatty acid composition of cell membrane was affected upon exposure to benzalkonium chloride. Sodium hypochlorite induced genes involved in sulfur and sulfur-containing amino acids metabolism, which correlated with the observed sodium hypochlorite-specific induction of oxidation of sulphydryl groups. Hydrogen peroxide and peracetic acid exposures induced genes involved in DNA damage and the SOS response. Notably, hydrogen peroxide and peracetic acid-treated cells exhibited higher mutation rates corroborating with the induced SOS response. Understanding the mechanisms displayed by microorganisms coping with disinfectants-induced stress may allow for design of more efficient sequential and/or disinfectant combination treatments in food processing environments.
2010-03-31 | GSE18807 | GEO
Project description:Sorbic acid (SA) is widely used as a preservative, but the effect of SA on spore germination and outgrowth has gained limited attention up to now. Therefore, the effect of sorbic acid on germination of spores of B. cereus strain ATCC 14579 was analyzed both at phenotype and transcriptome level. Spore germination and outgrowth was assessed at pH 5.5 without and with 0.75, 1.5 and 3.0mM (final concentrations) undissociated sorbic acid (HSA). This resulted in distinct HSA concentration-dependent phenotypes, varying from delays in germination and outgrowth to complete blockage of germination at 3.0mM HSA. The phenotypes reflecting different stages in the germination process could be confirmed using flow cytometry and could be recognized at transcriptome level by distinct expression profiles. In the absence and presence of 0.75 and 1.5mM HSA, similar cellular ATP levels were found up to the initial stage of outgrowth, suggesting that HSA-induced inhibition of outgrowth is not caused by depletion of ATP. Transcriptome analysis revealed the presence of a limited number of transcripts in dormant spores, outgrowth related expression, and genes specifically associated with sorbic acid stress, including alterations in cell envelope and multi-drug resistance. The potential role of these HSA-stress associated genes in spore outgrowth is discussed.
2010-11-01 | GSE19186 | GEO
Project description:The aim of the study was to carry out a CGH study utilizing a set of 39 diverse Bacillus isolates. Thirty four B. cereus and five B. anthracis strains and isolates were chosen so as to represent different lineages based on previous characterizations, including MLEE and MLST (Helgason, Okstad et al. 2000; Helgason, Tourasse et al. 2004). They represent the spectrum of B. cereus phenotypic diversity by including soil, dairy and periodontal isolates in addition to virulent B. anthracis strains.
2009-11-25 | GSE19068 | GEO
Project description:Sorbic acid (SA) is widely used as a preservative, but the effect of SA on spore germination and outgrowth has gained limited attention up to now. Therefore, the effect of sorbic acid on germination of spores of B. cereus strain ATCC 14579 was analyzed both at phenotype and transcriptome level. Spore germination and outgrowth was assessed at pH 5.5 without and with 0.75, 1.5 and 3.0mM (final concentrations) undissociated sorbic acid (HSA). This resulted in distinct HSA concentration-dependent phenotypes, varying from delays in germination and outgrowth to complete blockage of germination at 3.0mM HSA. The phenotypes reflecting different stages in the germination process could be confirmed using flow cytometry and could be recognized at transcriptome level by distinct expression profiles. In the absence and presence of 0.75 and 1.5mM HSA, similar cellular ATP levels were found up to the initial stage of outgrowth, suggesting that HSA-induced inhibition of outgrowth is not caused by depletion of ATP. Transcriptome analysis revealed the presence of a limited number of transcripts in dormant spores, outgrowth related expression, and genes specifically associated with sorbic acid stress, including alterations in cell envelope and multi-drug resistance. The potential role of these HSA-stress associated genes in spore outgrowth is discussed. Per concentration of undissociated sorbic acid (0, 0.75, and 1.5mM) four exposure times (10, 30, 60, and 120 minutes) were each compared with dormant spores (i.e., t0). The experiments were performed in duplicate and the duplicate samples were hybridized with a dye-swap
2010-11-01 | E-GEOD-19186 | biostudies-arrayexpress