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Zhuohui Liu,* Fan Zhang,* Fengfeng Jia, Shuling Li, Chaowu Jiang, Biao Ruan, Ruiqing Long Department of Otolaryngology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, People’s Republic of China*These authors contributed equally to this workCorrespondence: Ruiqing Long, Department of Otolaryngology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, People’s Republic of China, Email longruiqing@ydyy.cnPurpose: Chronic suppurative otitis media (CSOM) is a prominent contributor to preventable hearing loss globally. Probiotic therapy has attracted research interest in human infectious and inflammatory disease. As the most prevalent probiotic, the role of Lactobacillus in CSOM remains poorly defined. This study aimed to investigate the antipathogenic effects and underlying mechanism of Lactobacillus on CSOM.Methods: RNA sequencing of granulation of middle ear cavity from CSOM patients and lavage fluid of middle ear from normal volunteer was conducted. Human middle ear epithelial cells (HMEEC) and rats infected with Bacillus cereus (B. cereus) and Staphylococcus aureus (S. aureus) were used for CSOM constructing. Western blot, qPCR and Vybrant™ Alexa Fluor™ 488 lipid raft labeling were performed to explore the possible molecular mechanism by which lipid raft linker (RFTN1) regulates lipid raft/toll-like receptor 4 (TLR4). ELISA and HE staining was utilized to evaluate the effect of Lactobacillus on the progression of CSOM in vivo.Results: Based on RNA Sequence analysis, a total of 3646 differentially expressed genes (1620 up-regulated and 2026 down-regulated) were identified in CSOM. RFTN1 was highly expressed in CSOM. Inhibition of RFTN1 not only reduced the inflammatory response of CSOM but also suppressed the formation of lipid rafts. Further investigation revealed that RFTN1 inhibition could reduce the expression of TLR4, which also localizes to the lipid rafts. TLR4 responds to RFTN1-mediated inflammatory responses in CSOM. We treated the CSOM model with Lactobacillus, which has great potential for alleviating the inflammatory response, and found that Lactobacillus attenuated the development of CSOM by reducing RFTN1 and TLR4 expression.Conclusion: In conclusion, these findings suggest a crucial role for Lactobacillus in alleviating CSOM progression and uncovered the molecular mechanism involving Lactobacillus-regulated inhibition of the RFTN1-lipid raft-TLR4 signaling pathway under CSOM conditions.Keywords: CSOM, Lactobacillus, RFTN1, TLR4, S. aureus, B. cereus

Polyhydroxybutyrates (PHB) are granular polyesters synthesized by many bacteria as a carbon and energy source in environments where substances such as nitrogen, oxygen, carbon, and phosphorus are limited. Polyhydroxybutyrates is biodegradable, consisting of hydrophobic long chains, and is non-toxic. It is classified as one of the basic polymers of polyhydroxyalkanoates. In this study, the Polyhydroxybutyrates production of Bacillus cereus (ATCC 10876) and Cupriavidus necator (formerly Ralstonia eutropha ATCC17699) in the presence of different minimal carbon sources was investigated under static and shaking (150 rpm) states. According to the results of the research, the highest PHB production was observed in Bacillus cereus PBS + 1% xylose medium (7.395 µg/ml) in static conditions; Cupriavidus necator exhibited the highest production of polyhydroxybutyrates under shaking conditions in PBS + 1% fructose medium (9.626 µg/ml). The lowest polyhydroxybutyrates production was observed in Cupriavidus necator in PBS + 1% maltose medium (0.027 µg/ml) under static conditions; however, under shaking conditions, it was carried out in PBS + 1% dextrose medium (0.122 µg/ml). Considering these results, it is evident that there is an increase in the production of polyhydroxybutyrates by microorganisms as the shaking speed.

Abstract Background and aim Pathogenic Escherichia coli is a known harmful microorganism that takes advantage of favorable conditions to cause various infections in healthcare settings, such as bloodstream infections related to catheters, as well as infections in the urinary and respiratory tracts. E. coli utilizes biofilm development as a means to enhance its virulence and pathogenicity. This work aims to investigate the antibiofilm activity of α-amylase enzyme against uropathogenic E. coli (UPEC) and its effect on biofilm-regulatory genes. Methodology In this study, we evaluated the antibiofilm activity of α-amylase enzyme by spectrophotometric microtiter plate analysis and confocal laser scanning microscopy. Also, the antibacterial activity of the test enzyme was evaluated by measuring the MIC and MBC levels against UPEC. The quorum-quenching activity of α-amylase enzyme was assessed using a qRT-PCR to evaluate the impact on biofilm-regulatory genes. Results Based on our results, purified α-amylase showed MIC and MBC levels ranged between 128 and 512 µg /ml against UPEC isolates using broth microdilution assay. Crystal violet assay revealed MBIC of 128 µg/ml and MBEC of 256 µg/ml for the purified α-amylase. When the biofilm was analyzed by confocal laser scanning microscope, our results showed inhibition of biofilm thickness (56%) and live/dead cell percentages (43/55%). Furthermore, analysis of the effect on the expression of biofilm-encoding genes showed downregulation of both fimH and papC genes by 57 and 25%, respectively, upon treatment of UPEC with ½ of the MIC (64 µg/ml). Conclusions The results demonstrate that our purified α-amylase from B. cereus exhibits promising antibiofilm activities against UPEC at both phenotypic as well as genotypic levels. These findings suggest that this enzyme may serve as a natural effective tool for removing bacterial biofilms, potentially offering new therapeutic avenues for treating infections caused by UPEC.

Polyhydroxybutyrates (PHB) are granular polyesters synthesized by many bacteria as a carbon and energy source in environments where substances such as nitrogen, oxygen, carbon, and phosphorus are limited. Polyhydroxybutyrates is biodegradable, consisting of hydrophobic long chains, and is non-toxic. It is classified as one of the basic polymers of polyhydroxyalkanoates. In this study, the Polyhydroxybutyrates production of Bacillus cereus (ATCC 10876) and Cupriavidus necator (formerly Ralstonia eutropha ATCC17699) in the presence of different minimal carbon sources was investigated under static and shaking (150 rpm) states. According to the results of the research, the highest PHB production was observed in Bacillus cereus PBS + 1% xylose medium (7.395 µg/ml) in static conditions; Cupriavidus necator exhibited the highest production of polyhydroxybutyrates under shaking conditions in PBS + 1% fructose medium (9.626 µg/ml). The lowest polyhydroxybutyrates production was observed in Cupriavidus necator in PBS + 1% maltose medium (0.027 µg/ml) under static conditions; however, under shaking conditions, it was carried out in PBS + 1% dextrose medium (0.122 µg/ml). Considering these results, it is evident that there is an increase in the production of polyhydroxybutyrates by microorganisms as the shaking speed. [ABSTRACT FROM AUTHOR]

Milk rice pudding (MRP) is a commercial and popular dairy dessert, but owing to its characteristics and valuable ingredients, it may be contaminated by many pathogenic and spoilage microorganisms. So, this study aimed to improve the quality and safety of MRP by using cinnamon and clove essential oils. Concerning the evaluation of the minimum inhibitory concentration (MIC) for both oils with 0.2, 0.5, and 1% concentrations, B. cereus and B. subtilis were sensitive (+) to cinnamon and clove 0.5%, with inhibition zones of 13.3 and 14 mm for cinnamon and 11.3 and 12 mm for clove EO, respectively. While both bacteria were very sensitive (++) to cinnamon 1% (18.8 and 19.5 mm) and clove 1% (17.3 and 18.7 mm), respectively. Therefore, MRP was prepared by adding cinnamon and clove EOs at 0.6%. Treatments containing EOs showed a significant reduction of tested microorganisms compared to controls. B. cereus wasn’t detected in clove and cinnamon EO treatments at day 21 of the storage period, while B. subtilis vanished on day 14 for the cinnamon treatment and on day 21 for clove MRP. Moreover, the results revealed the enhancement of sensory characteristics of MRP supplemented with EOs without any significant alteration in their pH values. This study recommends the addition of cinnamon and clove EOs (0.6%) to MRP, as it isn’t only an excellent substitution of chemical preservatives with powerful antibacterial efficiency but also improves the overall acceptance of the product.

This study investigated the effects of low-pressure cold plasma on the inactivation of Bacillus cereus vegetative cells and spores in an inert matrix (borosilicate glass slide) and in rice grains, using oxygen as ionization gas. Greater reductions in B. cereus counts were observed in vegetative cells rather than spores. The experimental data obtained show that both the power of the plasma treatment and the matrix proved to be determining factors in the inactivation of both the spores and vegetative cells of B. cereus. To characterize the inactivation of B. cereus, experimental data were accurately fitted to the Weibull model. A significant decrease in parameter "a", representing resistance to treatment, was confirmed with treatment intensification. Furthermore, significant differences in the "a" value were observed between spores in inert and food matrices, suggesting the additional protective role of the food matrix for B. cereus spores. These results demonstrate the importance of considering matrix effects in plasma treatment to ensure the effective inactivation of pathogenic microorganisms, particularly in foods with low water activity, such as rice. This approach contributes to mitigating the impact of foodborne illnesses caused by pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

Milk rice pudding (MRP) is a commercial and popular dairy dessert, but owing to its characteristics and valuable ingredients, it may be contaminated by many pathogenic and spoilage microorganisms. So, this study aimed to improve the quality and safety of MRP by using cinnamon and clove essential oils. Concerning the evaluation of the minimum inhibitory concentration (MIC) for both oils with 0.2, 0.5, and 1% concentrations, B. cereus and B. subtilis were sensitive (+) to cinnamon and clove 0.5%, with inhibition zones of 13.3 and 14 mm for cinnamon and 11.3 and 12 mm for clove EO, respectively. While both bacteria were very sensitive (++) to cinnamon 1% (18.8 and 19.5 mm) and clove 1% (17.3 and 18.7 mm), respectively. Therefore, MRP was prepared by adding cinnamon and clove EOs at 0.6%. Treatments containing EOs showed a significant reduction of tested microorganisms compared to controls. B. cereus wasn't detected in clove and cinnamon EO treatments at day 21 of the storage period, while B. subtilis vanished on day 14 for the cinnamon treatment and on day 21 for clove MRP. Moreover, the results revealed the enhancement of sensory characteristics of MRP supplemented with EOs without any significant alteration in their pH values. This study recommends the addition of cinnamon and clove EOs (0.6%) to MRP, as it isn't only an excellent substitution of chemical preservatives with powerful antibacterial efficiency but also improves the overall acceptance of the product. [ABSTRACT FROM AUTHOR]

Hydrocarbon constituents of petroleum are persistent, bioaccumulated, and bio-magnified in living tissues, transported to longer distances, and exert hazardous effects on human health and the ecosystem. Bioaugmentation with microorganisms like bacteria is an emerging approach that can mitigate the toxins from environmental sources. The present study was initiated to target the petroleum-contaminated soil of gasoline stations situated in Lahore. Petroleum degrading bacteria were isolated by serial dilution method followed by growth analysis, biochemical and molecular characterization, removal efficiency estimation, metabolites extraction, and GC-MS of the metabolites. Molecular analysis identified the bacterium as Bacillus cereus, which exhibited maximum growth at 72 hours and removed 75% petroleum. Biochemical characterization via the Remel RapID™ ONE panel system showed positive results for arginine dehydrolase (ADH), ornithine decarboxylase (ODC), lysine decarboxylase (LDC), o-nitrophenyl-β-D-galactosidase (ONPG), p-nitrophenyl-β-D-glucosidase (βGLU), p-nitrophenyl-N-acetyl-β-D-glucosaminidase (NAG), malonate (MAL), adonitol fermentation (ADON), and tryptophane utilization (IND). GC-MS-based metabolic profiling identified alcohols (methyl alcohol, o-, p- and m-cresols, catechol, and 3-methyl catechol), aldehydes (methanone, acetaldehyde, and m-tolualdehyde), carboxylic acid (methanoic acid, cis,cis-muconic acid, cyclohexane carboxylic acid and benzoic acid), conjugate bases of carboxylic acids (benzoate, cis,cis-muconate, 4-hydroxybenzoate, and pyruvate) and cycloalkane (cyclohexene). It suggested the presence of methane, methylcyclohexane, toluene, xylene, and benzene degradation pathways in B. cereus.

Background: Bacillus cereus (B. cereus) biofilm is grown not only on medical devices but also on different substrata and is considered a potential hazard in the food industry. Quorum sensing (QS) plays a serious role in the synthesis of biofilm with its surrounding extracellular matrix enabling irreversible connection of the bacteria. Aim: The present study directed to determine the prevalence, antimicrobial resistance patterns, and biofilm formation ability of B. cereus in meat and meat products in Egypt. Methods: A total of one hundred and fifty meat and meat product samples were included in this study. The samples were transferred to the Bacteriology Laboratory for further bacteriological examination. Thereafter, the antimicrobial, antiquorum sensing and antibiofilm potential of apple cider vinegar (ACV) on B. cereus were evaluated. Results: Thirty four samples out of 150 samples (22.67%) were positive for B. cereus. Antimicrobial susceptibility testing revealed that all B. cereus isolates were resistant to ampicillin and colistin however none of them were resistant to ciprofloxacin and imipenem. All multidrug resistant (MDR) B. cereus isolates (n = 12) could produce biofilms with varying degrees; among them, 6 (50%), 3 (25%) and 3 (25%) isolates were weak, moderate and strong biofilm producers, respectively. Interestingly, the ACV exhibited marked inhibitory activities against B. cereus isolates with minimum inhibitory concentrations (MIC) ranging from 2 to 8 μg/mL. Moreover, it showed a good antibiofilm activity (> 50% reduction of biofilm formation) after exposure of biofilm producing B. cereus isolates to the minimum biofilm inhibitory concentrations 50 (MBIC50) of 4 μg/mL. Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) revealed down-regulation of biofilm genes (tasA and sipW) and their regulator (plcR) in strong biofilm producers in comparison to those of the control. Conclusion: Our study is the first report, which spotlight on the ACV activity against B. cereus biofilm and its consequence as a strong antibacterial and antibiofilm agent in food industry and human health risk. [Open Vet J 2024; 14(1.000): 186-199]

World health organization (WHO) recognizes antimicrobial resistance as a silent pandemic. It is estimated that 10 million deaths will occur annually due to antimicrobial resistant infections by 2050. Phytochemicals exhibit activity against drug resistant bacteria, offering potential for developing novel antibacterial agents. Garlic organosulphur compounds exhibit potent activity against a variety of drug-resistant bacteria. Identifying their mechanism of action is critical to assess their potential to be developed as novel antibacterial agents. Diallyl sulfide (DAS) is a component of garlic essential oil with antibacterial activity. In this study antibacterial activity of DAS was investigated against Bacillus cereus, a common foodborne pathogen. DAS exhibited activity against B. cereus with a minimum inhibitory concentration (MIC) of 54.75 mM. The presence of DAS significantly reduced the growth of B. cereus. The study also investigated the mechanism of antibacterial activity of DAS against B. cereus. Treating B. cereus with sub-MIC and MIC concentration of DAS resulted in a dose and time-dependent leakage of intracellular proteins. The protein leakage was enhanced at acidic pH. Scanning electron microscopy (SEM) of B. cereus treated with DAS showed deformation in the cell membrane. Thus, the data indicate that DAS exerts its antibacterial activity by compromising the membrane integrity of B. cereus. The study demonstrates DAS could be used to control B. cereus infections. The findings indicate that DAS has a membrane altering activity, suggesting that development of resistance to this mechanism is less likely and the compound could be novel antibacterial or a good adjuvant for antibiotics.

Background: Bacillus cereus (B. cereus) biofilm is grown not only on medical devices but also on different substrata and is considered a potential hazard in the food industry. Quorum sensing plays a serious role in the synthesis of biofilm with its surrounding extracellular matrix enabling irreversible connection of the bacteria. Aim: The goal of the current investigation was to ascertain the prevalence, patterns of antimicrobial resistance, and capacity for B. cereus biofilm formation in meat and meat products in Egypt. Methods: In all, 150 meat and meat product samples were used in this study. For additional bacteriological analysis, the samples were moved to the Bacteriology Laboratory. Thereafter, the antimicrobial, antiquorum sensing, and antibiofilm potential of apple cider vinegar (ACV) on B. cereus were evaluated. Results: Out of 150 samples, 34 (22.67%) tested positive for B. cereus. According to tests for antimicrobial susceptibility, every B. cereus isolates tested positive for colistin and ampicillin but negative for ciprofloxacin and imipenem. The ability to form biofilms was present in all 12 multidrug-resistant B. cereus isolates (n = 12); of these, 6 (50%), 3 (25%), and 3 (25%) isolates were weak, moderate, and strong biofilm producers, respectively. It is noteworthy that the ACV demonstrated significant inhibitory effects on B. cereus isolates, with minimum inhibitory concentrations varying between 2 and 8 μg/ml. Furthermore, after exposing biofilm-producing B. cereus isolates to the minimum biofilm inhibitory concentrations 50 of 4 μg/ml, it demonstrated good antibiofilm activity (>50% reduction of biofilm formation). Strong biofilm producers had down-regulated biofilm genes (tasA and sipW) and their regulator (plcR) compared to the control group, according to reverse transcriptase quantitative polymerase chain reaction analysis. Conclusion: Our study is the first report, that spotlights the ACV activity against B. cereus biofilm and its consequence as a strong antibacterial and antibiofilm agent in the food industry and human health risk. [ABSTRACT FROM AUTHOR]

Copyright of Terra Latinoamericana is the property of Sociedad Mexicana de la Ciencia del Suelo A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The physiology (membrane integrity, intracellular esterase and redox activity) of individual pathogenic bacteria is various in different growing phase, which has a profound significance for food safety testing and control. In this work, the aptamers against B. cereus in different growing phase was firstly selected based on whole bacterium-SELEX screening approach. Out of 32 candidate aptamers screened, aptamer B15 and B16 showed relatively high binding affinity with an apparent dissociation constant (Kd value) of 16.13 ± 4.98 nM and 20.67 ± 5.23 nM, respectively. A label-free impedance based aptasensor was further fabricated based on the screened aptamer, immobilized onto the GCE/Au surface. With the addition of B. cereus, the electron transfer process was prevented and exhibited a significant decrease in the electron-transfer resistance. Under optimal conditions, the fabricated aptasensor can achieve high sensitive detection of B. cereus as low as 10 cfu/mL. A satisfactory recovery of 90.5%–105.3% was achieved for the B. cereus detection in spiked milk samples, exhibiting its prospect in the sensitive detection of B. cereus in daily life.

This study investigated the effects of low-pressure cold plasma on the inactivation of Bacillus cereus vegetative cells and spores in an inert matrix (borosilicate glass slide) and in rice grains, using oxygen as ionization gas. Greater reductions in B. cereus counts were observed in vegetative cells rather than spores. The experimental data obtained show that both the power of the plasma treatment and the matrix proved to be determining factors in the inactivation of both the spores and vegetative cells of B. cereus. To characterize the inactivation of B. cereus, experimental data were accurately fitted to the Weibull model. A significant decrease in parameter “a”, representing resistance to treatment, was confirmed with treatment intensification. Furthermore, significant differences in the “a” value were observed between spores in inert and food matrices, suggesting the additional protective role of the food matrix for B. cereus spores. These results demonstrate the importance of considering matrix effects in plasma treatment to ensure the effective inactivation of pathogenic microorganisms, particularly in foods with low water activity, such as rice. This approach contributes to mitigating the impact of foodborne illnesses caused by pathogenic microorganisms.

Microorganisms are integral components of ecosystems, exerting profound impacts on various facets of human life. The recent United Nations General Assembly (UNGA) Science Summit emphasized the critical importance of comprehending the microbial world to address global challenges, aligning with the United Nations Sustainable Development Goals (SDGs). In agriculture, microbes are pivotal contributors to food production, sustainable energy, and environmental bioremediation. However, decades of agricultural intensification have boosted crop yields at the expense of soil health and microbial diversity, jeopardizing global food security. To address this issue, a study in West Bengal, India, explored the potential of a novel multi-strain consortium of plant growth promoting (PGP) Bacillus spp. for soil bioaugmentation. These strains were sourced from the soil’s native microbial flora, offering a sustainable approach. In this work, a composite inoculum of Bacillus zhangzhouensis MMAM, Bacillus cereus MMAM3), and Bacillus subtilis MMAM2 were introduced into an over-exploited agricultural soil and implications on the improvement of vegetative growth and yield related traits of Gylcine max (L) Meril. plants were evaluated, growing them as model plant, in pot trial condition. The study’s findings demonstrated significant improvements in plant growth and soil microbial diversity when using the bacterial consortium in conjunction with vermicompost. Metagenomic analyses revealed increased abundance of many functional genera and metabolic pathways in consortium-inoculated soil, indicating enhanced soil biological health. This innovative bioaugmentation strategy to upgrade the over-used agricultural soil through introduction of residual PGP bacterial members as consortia, presents a promising path forward for sustainable agriculture. The rejuvenated patches of over-used land can be used by the small and marginal farmers for cultivation of resilient crops like soybean. Recognizing the significance of multi-strain PGP bacterial consortia as potential bioinoculants, such technology can bolster food security, enhance agricultural productivity, and mitigate the adverse effects of past agricultural activities. [ABSTRACT FROM AUTHOR]

The soil-dwelling delta-proteobacterium Myxococcus xanthus is a model organism to study predation and competition. M. xanthus preys on a broad range of bacteria mediated by lytic enzymes, exopolysaccharides, Type-IV pilus-based motility, and specialized metabolites. Competition between M. xanthus and prey bacterial strains with various specialized metabolite profiles indicates a range of fitness, suggesting that specialized metabolites contribute to prey survival. To expand our understanding of how specialized metabolites affect predator–prey dynamics, we assessed interspecies interactions between M. xanthus and two strains of Bacillus cereus. While strain ATCC 14579 resisted predation, strain T was found to be highly sensitive to M. xanthus predation. The interaction between B. cereus ATCC 14579 and M. xanthus appears to be competitive, resulting in population loss for both predator and prey. Genome analysis revealed that ATCC 14579 belongs to a clade that possesses the biosynthetic gene cluster for production of thiocillins, whereas B. cereus strain T lacks those genes. Further, purified thiocillin protects B. cereus strains unable to produce this specialized metabolite, strengthening the finding that thiocillin protects against predation and contributes to the ecological fitness of B. cereus ATCC 14579. Lastly, strains that produce thiocillin appear to confer some level of protection to their own antibiotic by encoding an additional copy of the L11 ribosomal protein, a known target for thiopeptides. This work highlights the importance of specialized metabolites affecting predator–prey dynamics in soil microenvironments. [ABSTRACT FROM AUTHOR]

Bacillus cereus is a foodborne pathogen that has a widespread presence in the environment and frequently found in foods especially in dairy products. Raw milk contaminated with B. cereus could be the cause of its widespreadness in the environment. In this study, it was aimed to determine the genotypes, biofilm formation, antimicrobial susceptibilities, and antibiotypes of B. cereus isolates from raw milk. For this aim, B. cereus isolated and identified from 10 of 250 raw milk samples were investigated. Biofilm forming abilities were determined in vitro by Congo Red Agar Method. Kirby Bauer Disc Diffusion Method was used for determining the antibiotic susceptibilities of the isolates. According to the antibiotic susceptibility results, quantitative antibiotyping was implemented. Genotyping of the isolates were performed by RAPD-PCR. Biofilm formation was determined in 40% of the isolates. The resistances against amoxicillin-clavulanic acid, gentamicin, erythromycin, vancomycin, chloramphenicol, tetracycline, trimethoprim-sulfamethoxazole were determined in 100%, 0%, 30%, 0%, 0%, 0%, and 50% of the isolates, respectively. In the quantitative antibiotyping, the isolates showed similarity between 0.75 to 1.00. The phylogenetic similarities were calculated between 29% to 82%. In conclusion, raw milks might threat the public health because of having potential of containing the antibiotic resistant B. cereus.

Microorganisms are integral components of ecosystems, exerting profound impacts on various facets of human life. The recent United Nations General Assembly (UNGA) Science Summit emphasized the critical importance of comprehending the microbial world to address global challenges, aligning with the United Nations Sustainable Development Goals (SDGs). In agriculture, microbes are pivotal contributors to food production, sustainable energy, and environmental bioremediation. However, decades of agricultural intensification have boosted crop yields at the expense of soil health and microbial diversity, jeopardizing global food security. To address this issue, a study in West Bengal, India, explored the potential of a novel multi-strain consortium of plant growth promoting (PGP) Bacillus spp. for soil bioaugmentation. These strains were sourced from the soil’s native microbial flora, offering a sustainable approach. In this work, a composite inoculum of Bacillus zhangzhouensis MMAM, Bacillus cereus MMAM3), and Bacillus subtilis MMAM2 were introduced into an over-exploited agricultural soil and implications on the improvement of vegetative growth and yield related traits of Gylcine max (L) Meril. plants were evaluated, growing them as model plant, in pot trial condition. The study’s findings demonstrated significant improvements in plant growth and soil microbial diversity when using the bacterial consortium in conjunction with vermicompost. Metagenomic analyses revealed increased abundance of many functional genera and metabolic pathways in consortium-inoculated soil, indicating enhanced soil biological health. This innovative bioaugmentation strategy to upgrade the over-used agricultural soil through introduction of residual PGP bacterial members as consortia, presents a promising path forward for sustainable agriculture. The rejuvenated patches of over-used land can be used by the small and marginal farmers for cultivation of resilient crops like soybean. Recognizing the significance of multi-strain PGP bacterial consortia as potential bioinoculants, such technology can bolster food security, enhance agricultural productivity, and mitigate the adverse effects of past agricultural activities.

The soil-dwelling delta-proteobacterium Myxococcus xanthus is a model organism to study predation and competition. M. xanthus preys on a broad range of bacteria mediated by lytic enzymes, exopolysaccharides, Type-IV pilus-based motility, and specialized metabolites. Competition between M. xanthus and prey bacterial strains with various specialized metabolite profiles indicates a range of fitness, suggesting that specialized metabolites contribute to prey survival. To expand our understanding of how specialized metabolites affect predator–prey dynamics, we assessed interspecies interactions between M. xanthus and two strains of Bacillus cereus. While strain ATCC 14579 resisted predation, strain T was found to be highly sensitive to M. xanthus predation. The interaction between B. cereus ATCC 14579 and M. xanthus appears to be competitive, resulting in population loss for both predator and prey. Genome analysis revealed that ATCC 14579 belongs to a clade that possesses the biosynthetic gene cluster for production of thiocillins, whereas B. cereus strain T lacks those genes. Further, purified thiocillin protects B. cereus strains unable to produce this specialized metabolite, strengthening the finding that thiocillin protects against predation and contributes to the ecological fitness of B. cereus ATCC 14579. Lastly, strains that produce thiocillin appear to confer some level of protection to their own antibiotic by encoding an additional copy of the L11 ribosomal protein, a known target for thiopeptides. This work highlights the importance of specialized metabolites affecting predator–prey dynamics in soil microenvironments.

Introduction: Astragalus membranaceus Fisch. ex Bunge is a traditional botanical drug with antibacterial, antioxidant, antiviral, and other biological activities. In the process of industrialization of A. membranaceus, most of the aboveground stems and leaves are discarded without resource utilization except for a small amount of low-value applications such as composting. This study explored the antibacterial activity of A. membranaceus stem and leaf extracts to evaluate its potential as a feed antibiotic substitute. Materials and methods: The antibacterial activity of the flavonoid, saponin, and polysaccharide fractions in A. membranaceus stems and leaves was evaluated by the disk diffusion method. The inhibitory activity of the flavonoid fraction from A. membranaceus stems and leaves on B. cereus was explored from the aspects of the growth curve, cell wall, cell membrane, biofilm, bacterial protein, and virulence factors. On this basis, the flavonoid fraction in A. membranaceus stems and leaves were isolated and purified by column chromatography to determine the main antibacterial components. Results: The flavonoid fraction in A. membranaceus stems and leaves had significant inhibitory activity against B. cereus, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were 1.5625 and 6.25 mg/mL, respectively. A. membranaceus stem and leaf flavonoid fraction can induce death of B. cereus in many ways, such as inhibiting growth, destroying cell wall and cell membrane integrity, inhibiting biofilm formation, inhibiting bacterial protein synthesis, and downregulating virulence factor expression. In addition, it was clear that the main flavonoid with antibacterial activity in A. membranaceus stems and leaves was isoliquiritigenin. Molecular docking showed that isoliquiritigenin could form a hydrogen bonding force with FtsZ. Conclusion: A. membranaceus stem and leaf flavonoid fractions had significant inhibitory activity against B. cereus, and the main chemical composition was isoliquiritigenin. [ABSTRACT FROM AUTHOR]

Background and Aim: Bacillus cereus is accountable for several outbreaks of diseases spread by food. Therefore, the study aimed to use routine culture methods and direct PCR to detect the foodborne bacterial pathogen and its enterotoxins. Materials and Methods: In the present study, a total of 75 Kibda sandwiches, Sausage sandwiches, Chicken Luncheons, Beef Meat luncheons, and Chicken shawarma (Fifteen samples of each) were collected from different places in Kafr El-Sheikh governorate, Egypt, from July to September 2022. isolation, identification, and rapid analysis by PCR were done to find Foodborne bacterial pathogens in samples. Results: Bacterial isolation revealed 17 positive samples from different food types. From 17 infected samples, 40% were Kibda, 26.6% were Sausage, 20% were Chicken luncheon, and 13.3% were positive for Meat luncheon and Chicken shawarma sandwiches. Using PCR to identify B. cereus from positive isolates (group A), 8 isolates were detected having groEL, nhe & cytK genes amplified at 533, 766, and 421 bp, respectively. Also, the PCR, which was used to detection of Bacillus cereus directly in positive samples (group B) and revealed that 8 B. cereus in samples with its enterotoxins genes nhe & cytK, while group C which representssome random food samples of negative isolation resultsrevealed that 3 samples were infected by B. cereus. Conclusion: PCR assay was a sensitive & specific diagnostic tool in detecting Bacillus cereus with its enterotoxins genes directly from food samples, even in the presence of low numbers of B. cereus bacteria that traditional isolation and identification methods cannot detect. [ABSTRACT FROM AUTHOR]

Copyright of Kafkas Universitesi Veteriner Fakultesi Dergisi is the property of University of Kafkas, Faculty of Veterinary Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Bacillus cereus group includes species that act as food-borne pathogens causing diarrheal and emetic symptoms. They are widely distributed and can be found in various foods. In this study, out of 550 samples of milk and cheeses, 139 (25.3%) were found to be contaminated by B. cereus sensu lato (s.l.). One isolate per positive sample was characterized by Multilocus Sequence Typing (MLST) and for the presence of ten virulence genes. Based on MLST, all isolates were classified into 73 different sequence types (STs), of which 12 isolates were assigned to new STs. Virulence genes detection revealed that 90% and 61% of the isolates harboured the nheABC and the hblCDA gene cluster, respectively. Ninety-four percent of the isolates harboured the enterotoxin genes entS and entFM; 8% of the isolates possessed the ces gene. Thirty-eight different genetic profiles were identified, suggesting a high genetic diversity. Our study clearly shows the widespread diffusion of potentially toxigenic isolates of B. cereus s.l. in milk and cheeses in the Apulia region highlighting the need to adopt GMP and HACCP procedures along every step of the milk and cheese production chain in order to reduce the public health risk linked to the consumption of foods contaminated by B. cereus s.l. [ABSTRACT FROM AUTHOR]

Conventional methods for the detection and differentiation of Bacillus cereus group species have drawbacks mostly due to the complexity of genetic discrimination between the Bacillus cereus species. Here, we describe a simple and straightforward assay based on the detected unamplified bacterial 16S rRNA by DNA nanomachine (DNM). The assay uses a universal fluorescent reporter and four all-DNA binding fragments, three of which are responsible for "opening up" the folded rRNA while the fourth stand is responsible for detecting single nucleotide variation (SNV) with high selectivity. Binding of the DNM to 16S rRNA results in the formation of the 10–23 deoxyribozyme catalytic core that cleaves the fluorescent reporter and produces a signal, which is amplified over time due to catalytic turnover. This developed biplex assay enables the detection of B. thuringiensis 16S rRNA at fluorescein and B. mycoides at Cy5 channels with a limit of detection of 30 × 103 and 35 × 103 CFU/mL, respectively, after 1.5 h with a hands-on time of ~10 min. The new assay may simplify the analysis of biological RNA samples and might be useful for environmental monitoring as a simple and inexpensive alternative to amplification-based nucleic acid analysis. The DNM proposed here may become an advantageous tool for detecting SNV in clinically significant DNA or RNA samples and can easily differentiate SNV under broadly variable experimental conditions and without prior amplification. [ABSTRACT FROM AUTHOR]

In the study, a previously isolated plant beneficial endophytic B. cereus CaB1 was selected for the detailed analysis by whole-genome sequencing. The WGS has generated a total of 1.9 GB high-quality data which was assembled into a 5,257,162 bp genome with G + C content of 35.2%. Interestingly, CaB1 genome was identified to have 40 genes with plant beneficial functions by bioinformatic analysis. At the same time, it also showed the presence of various virulence factors except the diarrhoeal toxin, cereulide. Upon comparative analysis of CaB1 with other B. cereus strains, it was found to have random distributions of virulence and plant growth promoting traits. The core genome phylogenetic analysis of the Bacillus cereus strains further showed the close relation of plant associated strains with isolates from spoiled food products. The observed genome flexibility of B. cereus thus indicates its ability to make use of diverse hosts, which can result either in beneficial or harmful effects. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the sufficiency of food safety practices in a catering company. The presence of some pathogenic and indicator bacteria was monitored in the samples collected from raw materials, food, food contact surfaces and workers' hands and various steps of the tas kebab (a Turkish meat stew) and salad processing lines. Bacillus cereus was found in ready-to-eat (RTE) tas kebab and RTE salad, while Listeria monocytogenes was isolated from RTE salad. Furthermore, it was observed that RTE salad contained coagulase-positive Staphylococcus aureus without staphylococcal enterotoxin production. The swab samples obtained from cutting board surfaces, knives and workers' hands contained high counts of total aerobic bacteria and some samples were contaminated with coliforms and coagulase-positive/negative staphylococci. The presence of B. cereus and L. monocytogenes in RTE foods is a serious threat to public health, especially in the catering business. Preventing the presence of toxin-producing bacteria in RTE food is a fundamental action. Also, the occurrence of L. monocytogenes in RTE salad and B. cereus in RTE tas kebab/salad samples showed insufficient cleaning/disinfection practices. As a result, hygiene practices and regular monitoring in the catering business are necessary for food safety.

Astronauts remote from Earth, not least those who will inhabit the Moon or Mars, are vulnerable to disease due to their reduced immunity, isolation from clinical support, and the disconnect from any buffering capacity provided by the Earth. Here, we explore potential risks for astronaut health, focusing on key aspects of the biology of Bacillus anthracis and other anthrax-like bacilli. We examine aspects of Bacillus cereus group genetics in relation to their evolutionary biology and pathogenicity; a new clade of the Bacillus cereus group, close related to B. anthracis, has colonized the International Space Station (ISS), is still present, and could in theory at least acquire pathogenic plasmids from the other B. cereus group strains. The main finding is that the genomic sequence alignments of the B. cereus group ISS strains revealed a high sequence identity, indicating they originated from the same strain and that a close look to the genetic variations among the strains suggesting they lived, or they are living, in a vegetative form in the ISS enough time to accumulate genetic variations unique for each single strains. [ABSTRACT FROM AUTHOR]

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Bacillus cereus is a gram-positive, anaerobic, spore-forming bacterium related to food poisoning in humans. Vomit and diarrhea are the symptoms of foodborne B. cereus infection caused by emetic toxins and three enterotoxins, respectively. This bacterium is broadly present in soil and foods such as vegetables, spices, milk, and meat. The antibiotics impenem, vancomycin, chloramphenicol, gentamicin, and ciprofloxacin are used for all susceptible strains of B. cereus. But these antibiotics cause side effects in the host due to the drug–host interaction; because the targeted proteins by the drugs are not pathogen specific proteins, they are similar to human proteins also. To overcome this problem, this study focused on identifying putative drug targets in the pathogen B. cereus and finding new drugs to inhibit the function of the pathogen. The identification of drug targets is a pipeline process, starting with the identification of targets non-homologous to human and gutmicrobiota proteins, finding essential proteins, finding other proteins that highly interact with these essential proteins that are also highly important for protein network stability, finding cytoplasmic proteins with a clear pathway and known molecular function, and finding non-druggable proteins. Through this process, two novel drug targets were identified in B. cereus. Among the various antibiotics, Gentamicin had showed good binding affinity with the identified novel targets through molecular modeling and docking studies using Prime and GLIDE module of Schrödinger. Hence, this study suggest that the identified novel drug targets may very useful in drug therapeutic field for finding inhibitors which are similar to Gentamicin and designing new formulation of drug molecules to control the function of the foodborne illness causing pathogen B. cereus.

Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) are standard indexes for determining disinfection effectiveness. Nevertheless, they are static values disregarding the kinetics at sub-MIC concentrations where adaptation, growth, stationary, and death phases can be observed. The understanding of these dynamic mechanisms is crucial to designing effective disinfection strategies. In this study, we studied the 48 h kinetics of Bacillus cereus and Escherichia coli cells exposed to sub-MIC concentrations of didecyldimethylammonium chloride (DDAC). Two mathematical models were employed to reproduce the experiments: the only-growth classical logistic model and a mechanistic model including growth and death dynamics. Although both models reproduce the lag, exponential and stationary phases, only the mechanistic model is able to reproduce the death phase and reveals the concentration dependence of the bactericidal/bacteriostatic activity of DDAC. This model could potentially be extended to study other antimicrobials and reproduce changes in optical density (OD) and colony-forming units (CFUs) with the same parameters and mechanisms of action. [ABSTRACT FROM AUTHOR]

Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) are standard indexes for determining disinfection effectiveness. Nevertheless, they are static values disregarding the kinetics at sub-MIC concentrations where adaptation, growth, stationary, and death phases can be observed. The understanding of these dynamic mechanisms is crucial to designing effective disinfection strategies. In this study, we studied the 48 h kinetics of Bacillus cereus and Escherichia coli cells exposed to sub-MIC concentrations of didecyldimethylammonium chloride (DDAC). Two mathematical models were employed to reproduce the experiments: the only-growth classical logistic model and a mechanistic model including growth and death dynamics. Although both models reproduce the lag, exponential and stationary phases, only the mechanistic model is able to reproduce the death phase and reveals the concentration dependence of the bactericidal/bacteriostatic activity of DDAC. This model could potentially be extended to study other antimicrobials and reproduce changes in optical density (OD) and colony-forming units (CFUs) with the same parameters and mechanisms of action.

The Bacillus cereus group includes species that act as food-borne pathogens causing diarrheal and emetic symptoms. They are widely distributed and can be found in various foods. In this study, out of 550 samples of milk and cheeses, 139 (25.3%) were found to be contaminated by B. cereus sensu lato (s.l.). One isolate per positive sample was characterized by Multilocus Sequence Typing (MLST) and for the presence of ten virulence genes. Based on MLST, all isolates were classified into 73 different sequence types (STs), of which 12 isolates were assigned to new STs. Virulence genes detection revealed that 90% and 61% of the isolates harboured the nheABC and the hblCDA gene cluster, respectively. Ninety-four percent of the isolates harboured the enterotoxin genes entS and entFM; 8% of the isolates possessed the ces gene. Thirty-eight different genetic profiles were identified, suggesting a high genetic diversity. Our study clearly shows the widespread diffusion of potentially toxigenic isolates of B. cereus s.l. in milk and cheeses in the Apulia region highlighting the need to adopt GMP and HACCP procedures along every step of the milk and cheese production chain in order to reduce the public health risk linked to the consumption of foods contaminated by B. cereus s.l.

This study was conducted to evaluate the sufficiency of food safety practices in a catering company. The presence of some pathogenic and indicator bacteria was monitored in the samples collected from raw materials, food, food contact surfaces and workers' hands and various steps of the tas kebab (a Turkish meat stew) and salad processing lines. Bacillus cereus was found in ready-to-eat (RTE) tas kebab and RTE salad, while Listeria monocytogenes was isolated from RTE salad. Furthermore, it was observed that RTE salad contained coagulase-positive Staphylococcus aureus without staphylococcal enterotoxin production. The swab samples obtained from cutting board surfaces, knives and workers' hands contained high counts of total aerobic bacteria and some samples were contaminated with coliforms and coagulase-positive/negative staphylococci. The presence of B. cereus and L. monocytogenes in RTE foods is a serious threat to public health, especially in the catering business. Preventing the presence of toxin-producing bacteria in RTE food is a fundamental action. Also, the occurrence of L. monocytogenes in RTE salad and B. cereus in RTE tas kebab/salad samples showed insufficient cleaning/disinfection practices. As a result, hygiene practices and regular monitoring in the catering business are necessary for food safety. [ABSTRACT FROM AUTHOR]

We report the safe and effective use of oral linezolid for treatment of Bacillus cereus sepsis in an extremely preterm neonate, previously fed with human donor milk, in which a Brevibacillus sp. was eventually found. Due to several predisposing factors, premature, very low birth weight newborns are extremely vulnerable to invasive infections by environmental pathogens. After vancomycin microbiologic treatment failure (despite adequate blood concentrations and clinical response), linezolid was chosen for its optimal enteral absorption and bioavailability, also after exhaustion of peripheral venous heritage. No adverse events were recorded, with clinical cure. We reviewed the literature on B. cereus infections in newborns, together with the available evidence on the use of linezolid in similar contexts. [ABSTRACT FROM AUTHOR]

In this study, we have isolated and characterized proteolytic soil bacteria and their alkaline protease. Based on 16S rRNA sequence analysis, 12 isolates with the highest protease activity were classified as B. subtilis and B. cereus groups. B. subtilis D9 isolate showing the highest protease activity was selected for in vitro and in silico analysis for its ِِAKD9 protease. The enzyme has a molecular mass of 48 kDa, exhibiting optimal activity at 50 °C pH 9.5, and showed high stability till 65 °C and pH 8–11 for 1 h. Fe3+‏ stimulated, but Zn2+ and Hg2+ strongly inhibited the protease activity. Also, the maximum inhibition with PMSF indicated serine protease-type of AKD9 protease. AkD9 alkaline serine protease gene showed high sequence similarity and close phylogenetic relationship with AprX serine protease of B. subtilis isolates. Functional prediction of AKD9 resulted in the detection of subtilase domain, peptidase_S8 family, and subtilase active sites. Moreover, prediction of physicochemical properties indicated that AKD9 serine protease is hydrophilic, thermostable, and alkali-halo stable. Secondary structure prediction revealed the dominance of the coils enhances AKD9 activity and stability under saline and alkaline conditions. Based on molecular docking, AKD9 showed very promising binding affinities towards casein substrate with expected intrinsic proteolytic activities matching our obtained in vitro results. In conclusion, AKD9 alkaline serine protease seems to be a significant candidate for industrial applications because of its stability, hydrophilicity, enhanced thermostability, and alkali-halo stability.

Astronauts remote from Earth, not least those who will inhabit the Moon or Mars, are vulnerable to disease due to their reduced immunity, isolation from clinical support, and the disconnect from any buffering capacity provided by the Earth. Here, we explore potential risks for astronaut health, focusing on key aspects of the biology of Bacillus anthracis and other anthrax-like bacilli. We examine aspects of Bacillus cereus group genetics in relation to their evolutionary biology and pathogenicity; a new clade of the Bacillus cereus group, close related to B. anthracis, has colonized the International Space Station (ISS), is still present, and could in theory at least acquire pathogenic plasmids from the other B. cereus group strains. The main finding is that the genomic sequence alignments of the B. cereus group ISS strains revealed a high sequence identity, indicating they originated from the same strain and that a close look to the genetic variations among the strains suggesting they lived, or they are living, in a vegetative form in the ISS enough time to accumulate genetic variations unique for each single strains.

Background: Bacillus cereus is one of the important pathogen, which can be found in food samples like milk and principally responsible for food poisoning. Metallo-beta-lactamase (MBL) genes present in the Bacillus cereus bacterium, which provide resistance to the bacteria against the extreme condition. The objective of this study is to carry out molecular detection of blaTEM, blaCTX-M and blaSHV MBL genes in B. cereus strains, isolated from infant dry milk samples. Methods: Total 50 samples of infant dry milk were collected from the drug store, and 19 samples were selected for this investigation. After morphological and biochemical characterization of suspected colonies which are obtained from infant dry milk samples, these isolates were confirmed for B. cereus. Antibiotic susceptibility tests were done as per criteria of Clinical and Laboratory Standards Institute (CLSI). The phenotypic confirmatory analysis was done in Mueller Hinton agar (MHA) plates with clavulanic acid. If inhibition diameter is ≥5 mm increases in the clavulanic acid (CA) containing plate than to a plate without CA, it confirmed the presence of MBL genes. PCR used for detection of MBL genes in the isolated strains. Results: PCR detected the blaCTX-M (100%), blaSHV (4%) and blaTEM (84.2%) gene of B. cereus in the infant dry milk. Conclusion: The study confirms that the infant dry milk is a good source of B. cereus, if dry milk has absorbed water content from the air and hence providing a perfect condition for the growth of the bacterium, so It should be kept airtight the dry milk and stored in the cold condition.

Bacillus cereus is rarely implicated when diarrheal cases in children are diagnosed in developing countries due to the lack of molecular methods to identify its enterotoxigenic genes. We report that out of 62 enterobacteria isolated from 70 stool samples collected from children hospitalized at the Mile 4 Hospital, Ebonyi State, Nigeria, 24 isolates were identified as B. cereus based on 16SrRNA gene sequence. The enterotoxins genes nheA and cytK2 were detected in 23 out of the 24 isolates, while hblC was detected in 19 isolates. B. cereus may be responsible for greater number of yearly incidences of acute childhood gastroenteritis in Nigeria., Competing Interests: Declaration of competing interest Authors Declare No Competing Interest., (Copyright © 2024 Indian Association of Medical Microbiologists. Published by Elsevier B.V. All rights reserved.)

The biosynthesis of silver nanoparticles is considered to be a feasible, green, and eco-friendly method. Silver nanoparticles (AgNPs) were synthesized using badminton ball tree (Parkia biglandulosa) leaf extract and their significant physiochemical properties were characterized. The aqueous extract of the leaf of P. biglandulosa act as a reducing as well as capping agent for the reduction of Ag+ ​ions. FTIR analysis was conducted to find out the compounds that were liable for the bio-reduction of silver ions and to study the functional groups present in P. bigalandulosa leaf extract. The biologically reduced silver nanoparticles showed a surface plasmon resonance at 439 ​nm as studied from the UV–visible absorption spectrum. TEM studies confirmed the shape of the nanoparticles to be spherical with an average diameter of 15 ​nm. The anti-bacterial properties of the prepared nanoparticles were tested against Bacillus cereus by well plate method. Biosynthesized silver nanoparticles (PbAgNPs) at 0.02 ​M concentration showed the most antibacterial activity with a zone of inhibition of 7 ​mm. The high biocompatibility of the PbAgNPs by using human skin fibroblast cell line was evaluated by Alamar Blue reduction assay. The PbAgNPs had shown the highest cell viability when compared to native nanoparticles, meanwhile, a significant increase in cell viability was noted for the nanoparticles. The biosynthetic approach for synthesis was found to be a facile, rapid, single-step, safe, and effective alternative to the conventional physical/chemical methods.

Bacillus cereus plays an often unrecognized role in food borne diseases. Food poisoning caused by this pathogen is manifested by either diarrhea or emesis. Due to the relatively high prevalence of emetic toxin cereulide associated food poisoning, methods for simple and reliable detection of cereulide producing strains are of utmost importance. Recently, two different studies reported on the application of MALDI-ToF MS for either the differentiation of emetic and non-emetic strains of B. cereus or for direct detection of cereulide from bacterial colony smears. However, for implementation of cereulide detection using MALDI-ToF MS in routine microbiological diagnostics additional investigations on the sensitivity and specificity as well as on the fitting into common workflows for bacterial identification are needed. These aspects prompted us to investigate open issues and to test sample preparation methods, commonly used for microbial identification for their suitability to detect the emetic toxin from bacteria. Based on our experimental findings we propose a workflow that allows identification of B. cereus and sensitive detection of cereulide in parallel, using linear-mode MALDI-ToF MS equipment. The protocol was validated in a blinded study and is based on the well-established ethanol/formic acid extraction method. Cereulide is detected in the ethanol wash solution of samples identified as B. cereus as peaks at m/z 1175 and 1191. Peak position difference of 16 Th (Thomson) indicates detection of the sodium and potassium adducts of cereulide. This sample treatment offers possibilities for further characterization by more sophisticated LC-MS-based methods. In summary, the ease of use and the achieved level of analytical sensitivity as well as the wide-spread availability of MALDI-ToF MS equipment in clinical microbiological laboratories provides a promising tool to improve and to facilitate routine diagnostics of B. cereus associated food intoxications.

In México Zea mays (maize) is a crop which demands nitrogen fertilizer (NIFE) as a NH4NO3 (ammonium nitrate), in that sense hiperfertilization causes soil's lost productivity. An altemative of solution to solve this problem is the reduction and the optimization of NIFE with inoculants based on genus and species of plant growth-promoting bacteria (PGPB). The aim of this study was to analyze the growth of Z. mays inoculated with Bacillus cereus and Micromono-spora echinospora at 50% reduced NIFE. An experimental design of randomized blocks was used with (NH4NO3) as NIFE at the dose 50% (5 g/L) for Z. mays inoculated with the PGPB: the response variables on its seed: germination percent, day to germination, its shoot and root phenology: height plant, number of leaves, and root long and biomass: aerial fresh weight, root fresh weight, aerial dry weight, root dry weight (AFW/RFW/ADW/RDW). Experimental data were analyzed by ANOVA and minimal significant difference (LSD). Results showed a positive effect of B. cereus and M. echinospora on Z. mays seed as well as at seedling and flowering stages, where Z. mays had a RDW of 3.5 g, numerical valué statistically different compared with 1.1 g of RDW of Z. mays fed with NIFE at 100% dose, not inoculated used as a relative control (RC) Those data suggested that the inoculation of Z. mays with B. cereus and M. echinospora improving radical absorption of NIFE reduce at 50%, due to PGBP were able to transform seed and root organic exudates into growth promoting vegetal compounds (GPVC) or phytohormons avoiding soil's lost productivity.

Background: Bacillus cereus is one of the important pathogen, which can be found in food samples like milk and principally responsible for food poisoning. Metallo-beta-lactamase (MBL) genes present in the Bacillus cereus bacterium, which provide resistance to the bacteria against the extreme condition. The objective of this study is to carry out molecular detection of blaTEM, blaCTX-M and blaSHV MBL genes in B. cereus strains, isolated from infant dry milk samples. Methods: Total 50 samples of infant dry milk were collected from the drug store, and 19 samples were selected for this investigation. After morphological and biochemical characterization of suspected colonies which are obtained from infant dry milk samples, these isolates were confirmed for B. cereus. Antibiotic susceptibility tests were done as per criteria of Clinical and Laboratory Standards Institute (CLSI). The phenotypic confirmatory analysis was done in Mueller Hinton agar (MHA) plates with clavulanic acid. If inhibition diameter is ≥5 mm increases in the clavulanic acid (CA) containing plate than to a plate without CA, it confirmed the presence of MBL genes. PCR used for detection of MBL genes in the isolated strains. Results: PCR detected the blaCTX-M (100%), blaSHV (4%) and blaTEM (84.2%) gene of B. cereus in the infant dry milk. Conclusion: The study confirms that the infant dry milk is a good source of B. cereus, if dry milk has absorbed water content from the air and hence providing a perfect condition for the growth of the bacterium, so It should be kept airtight the dry milk and stored in the cold condition. [ABSTRACT FROM AUTHOR]

Bacillus cereus is a gram-positive, anaerobic, spore-forming bacterium related to food poisoning in humans. Vomit and diarrhea are the symptoms of foodborne B. cereus infection caused by emetic toxins and three enterotoxins, respectively. This bacterium is broadly present in soil and foods such as vegetables, spices, milk, and meat. The antibiotics impenem, vancomycin, chloramphenicol, gentamicin, and ciprofloxacin are used for all susceptible strains of B. cereus. But these antibiotics cause side effects in the host due to the drug–host interaction; because the targeted proteins by the drugs are not pathogen specific proteins, they are similar to human proteins also. To overcome this problem, this study focused on identifying putative drug targets in the pathogen B. cereus and finding new drugs to inhibit the function of the pathogen. The identification of drug targets is a pipeline process, starting with the identification of targets non-homologous to human and gutmicrobiota proteins, finding essential proteins, finding other proteins that highly interact with these essential proteins that are also highly important for protein network stability, finding cytoplasmic proteins with a clear pathway and known molecular function, and finding non-druggable proteins. Through this process, two novel drug targets were identified in B. cereus. Among the various antibiotics, Gentamicin had showed good binding affinity with the identified novel targets through molecular modeling and docking studies using Prime and GLIDE module of Schrödinger. Hence, this study suggest that the identified novel drug targets may very useful in drug therapeutic field for finding inhibitors which are similar to Gentamicin and designing new formulation of drug molecules to control the function of the foodborne illness causing pathogen B. cereus. [ABSTRACT FROM AUTHOR]

Bacillus cereus plays an often unrecognized role in food borne diseases. Food poisoning caused by this pathogen is manifested by either diarrhea or emesis. Due to the relatively high prevalence of emetic toxin cereulide associated food poisoning, methods for simple and reliable detection of cereulide producing strains are of utmost importance. Recently, two different studies reported on the application of MALDI-ToF MS for either the differentiation of emetic and non-emetic strains of B. cereus or for direct detection of cereulide from bacterial colony smears. However, for implementation of cereulide detection using MALDI-ToF MS in routine microbiological diagnostics additional investigations on the sensitivity and specificity as well as on the fitting into common workflows for bacterial identification are needed. These aspects prompted us to investigate open issues and to test sample preparation methods, commonly used for microbial identification for their suitability to detect the emetic toxin from bacteria. Based on our experimental findings we propose a workflow that allows identification of B. cereus and sensitive detection of cereulide in parallel, using linear-mode MALDI-ToF MS equipment. The protocol was validated in a blinded study and is based on the well-established ethanol/formic acid extraction method. Cereulide is detected in the ethanol wash solution of samples identified as B. cereus as peaks at m/z 1175 and 1191. Peak position difference of 16 Th (Thomson) indicates detection of the sodium and potassium adducts of cereulide. This sample treatment offers possibilities for further characterization by more sophisticated LC-MS-based methods. In summary, the ease of use and the achieved level of analytical sensitivity as well as the wide-spread availability of MALDI-ToF MS equipment in clinical microbiological laboratories provides a promising tool to improve and to facilitate routine diagnostics of B. cereus associated food intoxications. [ABSTRACT FROM AUTHOR]

We report the safe and effective use of oral linezolid for treatment of Bacillus cereus sepsis in an extremely preterm neonate, previously fed with human donor milk, in which a Brevibacillus sp. was eventually found. Due to several predisposing factors, premature, very low birth weight newborns are extremely vulnerable to invasive infections by environmental pathogens. After vancomycin microbiologic treatment failure (despite adequate blood concentrations and clinical response), linezolid was chosen for its optimal enteral absorption and bioavailability, also after exhaustion of peripheral venous heritage. No adverse events were recorded, with clinical cure. We reviewed the literature on B. cereus infections in newborns, together with the available evidence on the use of linezolid in similar contexts.