Combination impacts of gamma radiation and low temperature on the toxin producing Bacillus cereus isolated from fried and steam rice

2021 ◽  
Author(s):  
Md. Kamruzzaman Munshi ◽  
Farzana Akter Sukhi ◽  
Roksana Huque ◽  
Arzina Hossain ◽  
Shamim Mahbub ◽  
...  
Keyword(s):  
Low Temperature ◽  
Gamma Radiation ◽  
Bacillus Cereus

scholarly journals Direct-Imaging-Based Quantification of Bacillus cereus ATCC 14579 Population Heterogeneity at a Low Incubation Temperature

2009 ◽  
Vol 76 (3) ◽  
pp. 927-930 ◽  
Author(s):  
Heidy M. W. den Besten ◽  
Diego Garcia ◽  
Roy Moezelaar ◽  
Marcel H. Zwietering ◽  
Tjakko Abee
Keyword(s):  
Low Temperature ◽  
Bacillus Cereus ◽  
Growth Temperature ◽  
Incubation Temperature ◽  
Membrane Integrity ◽  
Population Heterogeneity ◽  
Direct Imaging

ABSTRACT Bacillus cereus ATCC 14579 was cultured in microcolonies on Anopore strips near its minimum growth temperature to directly image and quantify its population heterogeneity at an abusive refrigeration temperature. Eleven percent of the microcolonies failed to grow during low-temperature incubation, and this cold-induced population heterogeneity could be partly attributed to the loss of membrane integrity of individual cells.

Zur Strahleninaktivierung von Ribonuclease

1968 ◽  
Vol 23 (7) ◽  
pp. 934-943 ◽  
Author(s):  
Horst Jung ◽  
Helga Schüssler
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Low Temperature ◽  
Gamma Radiation ◽  
Enzymatic Activity ◽  
Amino Acid Residue ◽  
Atomic Hydrogen ◽  
Active Components ◽  
Experimental Conditions ◽  
Elution Pattern

Dry ribonuclease was irradiated with 60Co gamma radiation in vacuo, under oxygen atmosphere, and at 77 °K. By chromatography on Sephadex G-50 active ribonuclease was separated from inactive radiation products. From the elution pattern and by ultracentrifugation it was shown that mainly unfolded dimers are formed by gamma irradiation of dry ribonuclease. Amino acid analysis of these various products shows that in all components cystine, methionine, tyrosine, phenylalanine, lysine, and histidine are destroyed with increasing dose whereas glycine shows a small increase. Thus, in ribonuclease irradiated in the dry state the same amino acids are changed as was found after irradiation in aqueous solutions. The radiosensitivity of dry ribonuclease shows an increase by the presence of oxygen of about 2 and a decrease at low temperature in vacuo of about 5. The same factors were also found for the alteration of amino acids, which means that under various experimental conditions amino acid destruction is proportional to loss of enzymatic activity of ribonuclease. The observed selectivity of amino acid destruction may be explained by energy migration or by the attack of atomic hydrogen liberated at random from the molecule. The total number of amino acids destroyed per ribonuclease molecule increases with dose. In enzymatically inactive products this value is always higher by one amino acid residue than in the active components. From this result and from the increase with dose it is concluded that after destruction of one amino acid residue the ribonuclease molecule has a probability (not depending on dose of irradiation) of 0.45 to become inactivated whereas in 55 per cent of all cases the molecule maintains its enzymatic activity.

Involvement of the CasK/R two-component system in optimal unsaturation of the Bacillus cereus fatty acids during low-temperature growth

2015 ◽  
Vol 213 ◽  
pp. 110-117 ◽  
Author(s):  
Sara Esther Diomandé ◽  
Christophe Nguyen-the ◽  
Tjakko Abee ◽  
Marcel H. Tempelaars ◽  
Véronique Broussolle ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Low Temperature ◽  
Bacillus Cereus ◽  
Two Component System ◽  
Temperature Growth ◽  
Component System ◽  
Low Temperature Growth ◽  
Two Component

scholarly journals Differential Involvement of the Five RNA Helicases in Adaptation of Bacillus cereus ATCC 14579 to Low Growth Temperatures

2010 ◽  
Vol 76 (19) ◽  
pp. 6692-6697 ◽  
Author(s):  
Franck Pandiani ◽  
Julien Brillard ◽  
Isabelle Bornard ◽  
Caroline Michaud ◽  
Stéphanie Chamot ◽  
...  
Keyword(s):  
Low Temperature ◽  
Bacillus Cereus ◽  
Rna Helicase ◽  
Growth Conditions ◽  
Rna Helicases ◽  
Cold Sensitive ◽  
Differential Involvement ◽  
Encoding Genes

ABSTRACT Bacillus cereus ATCC 14579 possesses five RNA helicase-encoding genes overexpressed under cold growth conditions. Out of the five corresponding mutants, only the ΔcshA, ΔcshB, and ΔcshC strains were cold sensitive. Growth of the ΔcshA strain was also reduced at 30°C but not at 37°C. The cold phenotype was restored with the cshA gene for the ΔcshA strain and partially for the ΔcshB strain but not for the ΔcshC strain, suggesting different functions at low temperature.

Diarrhoeal toxin production at low temperature by selected strains of Bacillus cereus

1997 ◽  
Vol 64 (4) ◽  
pp. 551-559 ◽  
Author(s):  
CHRISTOPHE FERMANIAN ◽  
CHRISTIANE LAPEYRE ◽  
JEAN-MARC FREMY ◽  
MAURICE CLAISSE
Keyword(s):  
Low Temperature ◽  
Bacillus Cereus ◽  
Chinese Hamster Ovary Cells ◽  
Chinese Hamster ◽  
Toxin Production ◽  
Detection Methods ◽  
Clinical Strain ◽  
Ovary Cells ◽  
Protein Assay ◽  
Foodborne Outbreaks

The growth of four Bacillus cereus strains producing diarrhoeal toxin at 32°C (F4433/73 and 29.155, isolated on the occasion of foodborne outbreaks, and F4581/76L and F4581/76R, two variants of a clinical strain), a weakly toxigenic strain isolated in routine analysis of food (3505M) and an emetic isolate (F3502/73) was investigated at low temperature. Biomass was determined by protein assay. Generation times were: for strain F3502/73, which grew at [ges ]12°C, 8·71 h (at 12°C); for other strains, which grew at [ges ]10°C, 10·2 to ∼18·9 h (at 10°C). Toxin production during growth was evaluated by a commercial kit (Oxoid) and by a toxicity test on Chinese hamster ovary cells. Strains F4433/73 and F4581/76, secreting high levels of diarrhoeal toxin during the exponential phase at 32°C, produced high levels of toxicity at 10°C until the stationary phase. Strain 29.155 had decreased toxin production at 10°C. Toxicities for cellular extracts remained low when compared with culture filtrates. A correlation was found between the toxicity values given by the two detection methods tested, and the suitability of both methods for the detection of potential poisoning isolates is discussed.

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