Thuricin 4AJ1, produced by Bacillus thuringiensis strain 4AJ1, showed inhibition activity against Bacillus cereus 0938 and ATCC 10987. It began to appear in the stationary phase and reached its maximum activity level of 209.958 U at 18 h against B. cereus 0938 and 285.689 U at 24 h against B. cereus ATCC 10987. Tricine-SDS-PAGE results showed that the partly purified thuricin 4AJ1 was about 6.5 kDa. The molecular weights of the known B. thuringiensis bacteriocins and the ones obtained by the two mainstream websites for predicting bacteriocins were inconsistent with the size of the thuricin 4AJ1, indicating that the bacteriocin obtained in this study may have a novel structure. Based on the biochemical properties, the thuricin 4AJ1 activities increased after treatment with proteinase K and lipase II, and were not affected by a-amylase, catalase, α-chymotrypsin VII and α-chymotrypsin II. It was heat tolerant, being active up to 90º C. In the pH 3-10 range, it maintained most of its activity. Finally, the sensitivity of the strain 4AJ1 to commonly used antibiotics was tested. In view of its stability and antibacterial activity, thuricin 4AJ1 may be applied as a food biopreservative.
- MeSH
- antibakteriální látky farmakologie MeSH
- Bacillus cereus účinky léků MeSH
- Bacillus thuringiensis chemie metabolismus MeSH
- bakteriociny chemie izolace a purifikace farmakologie MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- molekulová hmotnost MeSH
- potravinářská mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
Amides of betulinic acid with cystamine were synthesized to investigate their antimicrobial and antitumor activity, and their influence on the cell cycle and cell apoptosis. The former target amide (6) displayed cytotoxicity in CEM cell line after 72 h of treatment (IC50 = 3.0 ± 0.7 μM; TI = 20), and induced apoptosis by caspase-3/7 activation in CEM cells. The latter target amide (9) displayed antimicrobial activity against Streptococcus mutans (MIC 3.125 μM; MBC 3.125 μM) and Bacillus cereus (MIC 25 μM; MBC 25 μM). The achieved results demonstrate enhancing of their biological activity over that of the parent compounds. However, two intermediate compounds (2 and 7) displayed either considerable cytotoxicity (2; 7.5 ± 0.8 μM; TI = 10, against G361) or antimicrobial activity (7; both against Actinomyces odontolycus and Clostridium perfrigens with MIC 12.5 µM and MBC 12.5 µM). The experimental data were compared with the in silico calculated physico-chemical and ADME parameters of the target compounds, including successful intermediates.
- MeSH
- Actinomyces účinky léků MeSH
- amidy chemie farmakologie MeSH
- antibakteriální látky chemická syntéza chemie farmakologie MeSH
- antitumorózní látky chemická syntéza chemie farmakologie MeSH
- apoptóza účinky léků MeSH
- Bacillus cereus účinky léků MeSH
- Clostridium účinky léků MeSH
- cystamin chemie farmakologie MeSH
- kultivované buňky MeSH
- léky antitumorózní - screeningové testy MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- molekulární konformace MeSH
- proliferace buněk účinky léků MeSH
- Streptococcus mutans účinky léků MeSH
- triterpeny chemie farmakologie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A novel Bacillus thuringiensis (Bt) bacteriocin BtCspB, active against a food-borne pathogen Bacillus cereus, was identified and purified by a traditional four-step chromatographic process with low yield (44.5 µg/L) in our lab previously. The aim of this study was to dramatically increase its yield by heterologous expression of BtCspB. The BtCspB gene from Bt BRC-ZYR2 was successfully heterologously expressed in Escherichia coli BL21 (DE3). Affinity chromatography was used to obtain the pure BtCspB up to 20 mg/L. The purified BtCspB showed a MIC value of 12.5 µg/mL and a MBC value of 50.0 µg/mL against Bacillus cereus ATCC 10987. The bacteriocin activity of BtCspB against B. cereus ATCC 10987 was further directly detected in a gel-overlay assay. The anti-B. cereus activity, however, was lower than the bacteriocin purified by the traditional four-step chromatographic process probably because of structural modifications. Compared with the traditional method, the yield of the bacteriocin by heterologous expression increased by 449 times, and the purification step was dramatically simplified, which laying a foundation for the industrial production of this novel cold-shock protein-like bacteriocin BtCspB active against B. cereus.
- MeSH
- Bacillus cereus účinky léků MeSH
- Bacillus thuringiensis genetika metabolismus MeSH
- bakteriální proteiny genetika izolace a purifikace farmakologie MeSH
- bakteriociny farmakologie MeSH
- Escherichia coli genetika růst a vývoj MeSH
- mikrobiální testy citlivosti MeSH
- Publikační typ
- časopisecké články MeSH
Bacterial metabolites with communicative functions could provide protection against stress conditions to members of the same species. Yet, information remains limited about protection provided by metabolites in Bacillus cereus and inter-species. This study investigated the effect of extracellular compounds derived from heat shocked (HS) and non-HS cultures of B. cereus and Geobacillus stearothermophilus on the thermotolerance of non-HS vegetative and sporulating B. cereus. Cultures of B. cereus and G. stearothermophilus were subjected to HS (42 or 65 °C respectively for 30 min) or non-HS treatments. Cells and supernatants were separated, mixed in a combined array, and then exposed to 50 °C for 60 min and viable cells determined. For spores, D values (85 and 95 °C) were evaluated after 120 h. In most cases, supernatants from HS B. cereus cultures added to non-HS B. cereus cells caused their thermotolerance to increase (D 50 12.2-51.9) when compared to supernatants from non-HS cultures (D 50 7.4-21.7). While the addition of supernatants from HS and non-HS G. stearothermophilus cultures caused the thermotolerance of non-HS cells from B. cereus to decrease initially (D 50 3.7-7.1), a subsequent increase was detected in most cases (D 50 18-97.7). In most cases, supernatants from sporulating G. stearothermophilus added to sporulating cells of B. cereus caused the thermotolerance of B. cereus 4810 spores to decline, whereas that of B. cereus 14579 increased. This study clearly shows that metabolites in supernatants from either the same or different species (such as G. stearothermophilus) influence the thermotolerance of B. cereus.
- MeSH
- Bacillus cereus účinky léků metabolismus fyziologie účinky záření MeSH
- Geobacillus stearothermophilus metabolismus fyziologie účinky záření MeSH
- mikrobiální interakce * MeSH
- mikrobiální viabilita účinky léků účinky záření MeSH
- spory bakteriální účinky léků fyziologie účinky záření MeSH
- teplota MeSH
- termotolerance účinky léků MeSH
- vysoká teplota MeSH
- Publikační typ
- časopisecké články MeSH
A novel approach was developed for rapid assessment of bioavailability and potential mobility of contaminants in soil. The response of the same test organism to the organic extract, water extract and solid phase of soil was recorded and compared. This approach was designed to give an initial estimate of the total organic toxicity (response to organic extractable fraction), as well as the mobile (response to water extract) and bioavailable fraction (response to solid phase) of soil samples. Eighteen soil samples with different levels of pollution and content of organic carbon were selected to validate the novel three-step ecotoxicological evaluation approach. All samples were chemically analysed for priority contaminants, including aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), hexachlorocyclohexane (HCH) and dichlordiphenyltrichloroethane (DDT). The ecotoxicological evaluation involved determination of toxicity of the organic, mobile and bioavailable fractions of soil to the test organism, bacterium Bacillus cereus. We found a good correlation between the chemical analysis and the toxicity of organic extract. The low toxicity of water extracts indicated low water solubility, and thus, low potential mobility of toxic contaminants present in the soil samples. The toxicity of the bioavailable fraction was significantly greater than the toxicity of water-soluble (mobile) fraction of the contaminants as deduced from comparing untreated samples and water extracts. The bioavailability of the contaminants decreased with increasing concentrations of organic carbon in evaluated soil samples. In conclusion, the three-step ecotoxicological evaluation utilised in this study can give a quick insight into soil contamination in context with bioavailability and mobility of the contaminants present. This information can be useful for hazard identification and risk assessment of soil-associated contaminants. Graphical Abstract New three-step ecotoxicological evaluation by using the same organism.
- MeSH
- Bacillus cereus účinky léků MeSH
- biodegradace MeSH
- biologická dostupnost MeSH
- chlorované uhlovodíky * analýza toxicita MeSH
- ekotoxikologie metody MeSH
- hodnocení rizik MeSH
- látky znečišťující půdu * analýza toxicita MeSH
- polycyklické aromatické uhlovodíky * analýza toxicita MeSH
- půda chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Polyaniline colloids rank among promising application forms of this conducting polymer. Cytotoxicity, antibacterial activity, and neutrophil oxidative burst tests were performed on cells treated with colloidal polyaniline dispersions. The antibacterial effect of colloidal polyaniline against gram-positive and gram-negative bacteria was most pronounced for Bacillus cereus and Escherichia coli, with a minimum inhibitory concentration of 3,500 μg mL(-1). The data recorded on human keratinocyte (HaCaT) and a mouse embryonic fibroblast (NIH/3T3) cell lines using an MTT assay and flow cytometry indicated a concentration-dependent cytotoxicity of colloid, with the absence of cytotoxic effect at around 150 μg mL(-1). The neutrophil oxidative burst test then showed that colloidal polyaniline, in concentrations <150 μg mL(-1), was not able to stimulate the production of reactive oxygen species in neutrophils and whole human blood. However, it worked efficiently as a scavenger of those already formed.
- MeSH
- aniliny chemická syntéza chemie farmakologie MeSH
- antibakteriální látky chemická syntéza chemie farmakologie MeSH
- apoptóza účinky léků MeSH
- Bacillus cereus účinky léků MeSH
- buněčné linie MeSH
- buňky NIH 3T3 MeSH
- Escherichia coli účinky léků MeSH
- koloidy chemická syntéza chemie farmakologie MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- myši MeSH
- neutrofily účinky léků metabolismus MeSH
- povrchové vlastnosti MeSH
- Pseudomonas aeruginosa účinky léků MeSH
- reaktivní formy kyslíku metabolismus MeSH
- Staphylococcus aureus účinky léků MeSH
- velikost částic MeSH
- viabilita buněk účinky léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Twelve lactobacilli isolates from mucosa of 3-5-week-old weaned pigs were found to exert good antimicrobial activity against common porcine pathogens (S. aureus, B. cereus, E. coli, C. perfringens). Two of them produced in addition to lactic acid also considerable amounts of acetic acid, and 6 of them produced hydrogen peroxide and metabolites other than organic acids. Isolates 4/26 and 2/25 (identified as L. crispatus or L. amylovorus) were inhibitory against most strains of S. aureus, B. cereus and E. coli, and especially the strain 4/26 survived well in simulated gastric and intestinal juice. Diarrhea-causing E. coli O8K88H9 Ent(+) was successfully inhibited by the growing culture as well as by the catalase-treated and neutralized supernatant of L. reuteri 12/26. Mucin degradation and multiple resistance to antibiotics were not observed.
- MeSH
- antibiotická rezistence MeSH
- Bacillus cereus účinky léků MeSH
- Clostridium perfringens účinky léků MeSH
- Escherichia coli účinky léků MeSH
- feces mikrobiologie MeSH
- ileum mikrobiologie MeSH
- kultivační média speciální farmakologie MeSH
- kultivační média farmakologie chemie MeSH
- kyselina mléčná farmakologie MeSH
- Lactobacillus izolace a purifikace metabolismus účinky léků MeSH
- muciny metabolismus MeSH
- nemoci prasat prevence a kontrola MeSH
- odstavení MeSH
- peroxid vodíku metabolismus MeSH
- přirozená imunita MeSH
- probiotika MeSH
- Staphylococcus aureus účinky léků MeSH
- střevní sliznice mikrobiologie MeSH
- Sus scrofa mikrobiologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
A change in interaction with spores of Bacillus cereus occurred in the range of critical concentrations of micelle formation. With 1-methyldodecyldimethylamine-N-oxide and N,N'-bis(dodecyldimethyl)-1,2-ethanediammonium dibromide, the induced release of dipicolinic acid was blocked and the adsorption dynamics changed, respectively.
- MeSH
- adsorpce MeSH
- Bacillus cereus účinky léků metabolismus MeSH
- bakteriální adheze účinky léků MeSH
- dimethylaminy farmakokinetika farmakologie MeSH
- kvartérní amoniové sloučeniny farmakokinetika farmakologie MeSH
- micely MeSH
- povrchově aktivní látky farmakokinetika farmakologie MeSH
- spory bakteriální účinky léků metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- Bacillus cereus patogenita účinky léků MeSH
- dezinficiencia MeSH
- spory patogenita účinky léků MeSH
- sterilizace MeSH
- Publikační typ
- techniky in vitro MeSH
