Low Concentrations of Bile Salts Induce Stress Responses and Reduce Motility in Bacillus cereus ATCC 14579

ABSTRACT Tolerance to bile salts was investigated in forty Bacillus cereus strains, including 17 environmental isolates, 11 dairy isolates, 3 isolates from food poisoning outbreaks, and 9 other clinical isolates. Growth of all strains was observed at low bile salt concentrations, but no growth was observed on LB agar plates containing more than 0.005% bile salts. Preincubation of the B. cereus type strain, ATCC 14579, in low levels of bile salts did not increase tolerance levels. B. cereus ATCC 14579 was grown to mid-exponential growth phase and shifted to medium containing bile salts (0.005%). Global expression patterns were determined by hybridization of total cDNA to a 70-mer oligonucleotide microarray. A general stress response and a specific response to bile salts were observed. The general response was similar to that observed in cultures grown in the absence of bile salts but at a higher (twofold) cell density. Up-regulation of several putative multidrug exporters and transcriptional regulators and down-regulation of most motility genes were observed as part of the specific response. Motility experiments in soft agar showed that motility decreased following bile salts exposure, in accordance with the transcriptional data. Genes encoding putative virulence factors were either unaffected or down-regulated.

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Mild Intermittent Hypoxia Does Not Induce Stress Responses in the Neonatal Rat Brain

Neonatology ◽

10.1159/000087629 ◽

2005 ◽

Vol 88 (4) ◽

pp. 313-320 ◽

Cited By ~ 2

Author(s):

Valerie Boss ◽

Augusto Sola ◽

Tong-Chun Wen ◽

Michael J. Decker

Keyword(s):

Rat Brain ◽

Stress Responses ◽

Intermittent Hypoxia ◽

Neonatal Rat ◽

Induce Stress ◽

Neonatal Rat Brain

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Transcriptional and proteomic stress responses of a soil bacterium Bacillus cereus to nanosized zero-valent iron (nZVI) particles

Chemosphere ◽

10.1016/j.chemosphere.2013.05.082 ◽

2013 ◽

Vol 93 (6) ◽

pp. 1077-1083 ◽

Cited By ~ 48

Author(s):

C. Fajardo ◽

M.L. Saccà ◽

M. Martinez-Gomariz ◽

G. Costa ◽

M. Nande ◽

...

Keyword(s):

Bacillus Cereus ◽

Stress Responses ◽

Zero Valent Iron ◽

Soil Bacterium ◽

Bacterium Bacillus

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Exposure to Cadmium Elevates Expression of Genes in the OxyR and OhrR Regulons and Induces Cross-Resistance to Peroxide Killing Treatment in Xanthomonas campestris

Applied and Environmental Microbiology ◽

10.1128/aem.71.4.1843-1849.2005 ◽

2005 ◽

Vol 71 (4) ◽

pp. 1843-1849 ◽

Cited By ~ 55

Author(s):

Peerakan Banjerdkij ◽

Paiboon Vattanaviboon ◽

Skorn Mongkolsuk

Keyword(s):

Induced Resistance ◽

Stress Responses ◽

Xanthomonas Campestris ◽

Cadmium Toxicity ◽

Cross Resistance ◽

Organic Hydroperoxide ◽

Alkyl Hydroperoxide ◽

Expression Of Genes ◽

Low Concentrations ◽

Peroxide Stress

ABSTRACT Cadmium is an important heavy metal pollutant. For this study, we investigated the effects of cadmium exposure on the oxidative stress responses of Xanthomonas campestris, a soil and plant pathogenic bacterium. The exposure of X. campestris to low concentrations of cadmium induces cross-protection against subsequent killing treatments with either H2O2 or the organic hydroperoxide tert-butyl hydroperoxide (tBOOH), but not against the superoxide generator menadione. The cadmium-induced resistance to peroxides is due to the metal's ability to induce increased levels of peroxide stress protective enzymes such as alkyl hydroperoxide reductase (AhpC), monofunctional catalase (KatA), and organic hydroperoxide resistance protein (Ohr). Cadmium-induced resistance to H2O2 is dependent on functional OxyR, a peroxide-sensing transcription regulator. Cadmium-induced resistance to tBOOH shows a more complex regulatory pattern. The inactivation of the two major sensor-regulators of organic hydroperoxide, OxyR and OhrR, only partially inhibited cadmium-induced protection against tBOOH, suggesting that these genes do have some role in the process. However, other, as yet unknown mechanisms are involved in inducible organic hydroperoxide protection. Furthermore, we show that the cadmium-induced peroxide stress response is mediated by the metal's ability to predominately cause an increase in intracellular concentrations of organic hydroperoxide and, in part, H2O2. Analyses of various mutants of peroxide-metabolizing enzymes suggested that this increase in organic hydroperoxide levels is, at least in part, responsible for cadmium toxicity in Xanthomonas.

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PHOSPHATASE OF RABBIT POLYMORPHONUCLEAR LEUCOCYTES

Canadian Journal of Research ◽

10.1139/cjr49e-039 ◽

1949 ◽

Vol 27e (5) ◽

pp. 290-307 ◽

Cited By ~ 15

Author(s):

D. M. Cram ◽

R. J. Rossiter

Keyword(s):

Alkaline Phosphatase ◽

Enzyme Activity ◽

Acid Phosphatase ◽

Bile Salts ◽

Polymorphonuclear Leucocytes ◽

Alkyl Sulphate ◽

Low Concentrations ◽

Activity Curve ◽

Surface Active ◽

Active Substances

Rabbit polymorphonuclear leucocytes contain an active phosphatase that readily hydrolyzes disodium phenyl phosphate. The pH activity curve of the enzyme was found to have two maxima, one in the region of pH 10 and the other in the region of pH 5. The alkaline phosphatase was much more active than the acid phosphatase. The concentration of alkaline phosphatase in rabbit white cells was approximately one thousand times that of the enzyme in the serum. Under the conditions of study, the alkaline phosphatase activity was proportional to the concentration of the enzyme. The effect of substrate concentration on the enzyme activity was studied and the Michaelis constant (Ks) determined. An excess of substrate inhibited the enzyme. The course of the reaction was linear with time for the first 60 min.; after 90 min. the activity fell off faster than would be expected if the reaction were of the first order.Magnesium and glycine, in low concentrations, caused an increase in the enzyme activity, whereas zinc, cyanide, borate, phosphate, bile salts, and glycine, in higher concentrations, were inhibitory. Fluoride had no demonstrable effect. Surface-active substances, such as saponin, bile salts, or alkyl sulphate, liberated the enzyme from the cells. Similar results were obtained when α-glycerophosphate or β-glycerophosphate was used as the substrate.The alkaline phosphatase can be considered to belong to Class AI of Folley and Kay (22) and the acid phosphatase to Class AII. The alkaline phosphatase can also be considered to be a Phosphatase II of Cloetens (9).

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Impact of Phytochemicals on Viability and Cereulide Toxin Synthesis in Bacillus cereus Revealed by a Novel High-Throughput Method, Coupling an AlamarBlue-Based Assay with UPLC-MS/MS

Toxins ◽

10.3390/toxins13090672 ◽

2021 ◽

Vol 13 (9) ◽

pp. 672

Author(s):

Markus Kranzler ◽

Elrike Frenzel ◽

Veronika Walser ◽

Thomas F. Hofmann ◽

Timo D. Stark ◽

...

Keyword(s):

Bacillus Cereus ◽

High Throughput ◽

Food Poisoning ◽

Small Scale ◽

Natural Substances ◽

Viability Assay ◽

Food Borne ◽

Low Concentrations ◽

Hydroxycinnamic Acid Derivatives ◽

Antibacterial Potential

Due to its food-poisoning potential, Bacillus cereus has attracted the attention of the food industry. The cereulide-toxin-producing subgroup is of particular concern, as cereulide toxin is implicated in broadscale food-borne outbreaks and occasionally causes fatalities. The health risks associated with long-term cereulide exposure at low doses remain largely unexplored. Natural substances, such as plant-based secondary metabolites, are widely known for their effective antibacterial potential, which makes them promising as ingredients in food and also as a surrogate for antibiotics. In this work, we tested a range of structurally related phytochemicals, including benzene derivatives, monoterpenes, hydroxycinnamic acid derivatives and vitamins, for their inhibitory effects on the growth of B. cereus and the production of cereulide toxin. For this purpose, we developed a high-throughput, small-scale method which allowed us to analyze B. cereus survival and cereulide production simultaneously in one workflow by coupling an AlamarBlue-based viability assay with ultraperformance liquid chromatography–mass spectrometry (UPLC-MS/MS). This combinatory method allowed us to identify not only phytochemicals with high antibacterial potential, but also ones specifically eradicating cereulide biosynthesis already at very low concentrations, such as gingerol and curcumin.

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Correction to: Industrial antifoam agents impair ethanol fermentation and induce stress responses in yeast cells

Applied Microbiology and Biotechnology ◽

10.1007/s00253-017-8643-4 ◽

2017 ◽

Vol 102 (1) ◽

pp. 513-513

Author(s):

Jens Christian Nielsen ◽

Felipe Senne de Oliveira Lino ◽

Thomas Gundelund Rasmussen ◽

Jette Thykær ◽

Christopher T. Workman ◽

...

Keyword(s):

Stress Responses ◽

Ethanol Fermentation ◽

Yeast Cells ◽

Induce Stress

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Characterization of a Novel Lytic Protein Encoded by the Bacillus cereus E33L GeneampDas a Bacillus anthracis Antimicrobial Protein

Applied and Environmental Microbiology ◽

10.1128/aem.06906-11 ◽

2012 ◽

Vol 78 (8) ◽

pp. 3025-3027 ◽

Cited By ~ 7

Author(s):

Feliza A. Bourguet ◽

Brian E. Souza ◽

Angela K. Hinz ◽

Matthew A. Coleman ◽

Paul J. Jackson

Keyword(s):

Bacillus Cereus ◽

Bacillus Anthracis ◽

Antimicrobial Protein ◽

Cell Wall Biosynthesis ◽

Bacterial Genomes ◽

Content Type ◽

Highly Active ◽

Low Concentrations

ABSTRACTLytic proteins encoded by bacterial genomes have been implicated in cell wall biosynthesis and recycling. TheBacillus cereusE33LampDgene encodes a putativeN-acetylmuramoyl-l-alanine amidase. This gene, expressedin vitro, produced a very stable, highly active lytic protein. Very low concentrations rapidly and efficiently lyse vegetativeBacillus anthraciscells.

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Effects of bile salts on the plasma membranes of isolated rat hepatocytes

Biochemical Journal ◽

10.1042/bj1880321 ◽

1980 ◽

Vol 188 (2) ◽

pp. 321-327 ◽

Cited By ~ 99

Author(s):

D Billington ◽

C E Evans ◽

P P Godfrey ◽

R Coleman

Keyword(s):

Alkaline Phosphatase ◽

Bile Salt ◽

Bile Salts ◽

Plasma Membranes ◽

Rat Hepatocytes ◽

Isolated Hepatocytes ◽

Soluble Form ◽

Isolated Rat Hepatocytes ◽

Low Concentrations

The conjugated trihydroxy bile salts glycocholate and taurocholate removed approx. 20–30% of the plasma-membrane enzymes 5′-nucleotidase, alkaline phosphatase and alkaline phosphodiesterase I from isolated hepatocytes before the onset of lysis, as judged by release of the cytosolic enzyme lactate dehydrogenase. The conjugated dihydroxy bile salt glycodeoxycholate similarly removed 10–20% of the 5′-nucleotidase and alkaline phosphatase activities, but not alkaline phosphodiesterase activity; this bile salt caused lysis of hepatocytes at approx. 10-fold lower concentrations (1.5–2.0mM) than either glycocholate or taurocholate (12–16mM). At low concentrations (7 mM), glycocholate released these enzymes in a predominantly particulate form, whereas at higher concentrations (15 mM) glycocholate further released these components in a predominantly ‘soluble’ form. Inclusion of 1% (w/v) bovine serum albumin in the incubations had a small protective effect on the release of enzymes from hepatocytes by glycodeoxycholate, but not by glycocholate. These observations are discussed in relation to the possible role of bile salts in the origin of some biliary proteins.

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Role of Bacteriocin Immunity Proteins in the Antimicrobial Sensitivity of Streptococcus mutans

Journal of Bacteriology ◽

10.1128/jb.00908-06 ◽

2006 ◽

Vol 188 (23) ◽

pp. 8095-8102 ◽

Cited By ~ 46

Author(s):

Michiyo Matsumoto-Nakano ◽

Howard K. Kuramitsu

Keyword(s):

Quorum Sensing ◽

Streptococcus Mutans ◽

Stress Responses ◽

Antimicrobial Agents ◽

Protein Gene ◽

Immunity Protein ◽

Antimicrobial Sensitivity ◽

Sensing Systems ◽

Low Concentrations ◽

First Time

ABSTRACT Bacteria utilize quorum-sensing systems to modulate environmental stress responses. The quorum-sensing system of Streptococcus mutans is mediated by the competence-stimulating peptide (CSP), whose precursor is encoded by the comC gene. A comC mutant of strain GS5 exhibited enhanced antimicrobial sensitivity to a wide variety of different agents. Since the addition of exogenous CSP did not complement this phenotype, it was determined that the increased tetracycline, penicillin, and triclosan sensitivities resulted from repression of the putative bacteriocin immunity protein gene, bip, which is located immediately upstream from comC. We further demonstrated that the inactivation of bip or smbG, another bacteriocin immunity protein gene present within the smb operon in S. mutans GS5, affected sensitivity to a variety of antimicrobial agents. Furthermore, both the bip and smbG genes were upregulated in the presence of low concentrations of antibiotics and were induced during biofilm formation relative to in planktonic cells. These results suggest, for the first time, that the antimicrobial sensitivity of a bacterium can be modulated by some of the putative bacteriocin immunity proteins expressed by the organism. The implications of these observations for the evolution of bacteriocin immunity protein genes as well as for potential new chemotherapeutic strategies are discussed.

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