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Toxins Jun 2021sp. H16v8 and sp. HGD9229 were identified as Aflatoxin B (AFB) degrader in nutrient broth after a 12 h incubation at 37 °C. The degradation efficiency of the...
sp. H16v8 and sp. HGD9229 were identified as Aflatoxin B (AFB) degrader in nutrient broth after a 12 h incubation at 37 °C. The degradation efficiency of the two-strain supernatant on 100 μg/L AFB was higher than the bacterial cells and cell lysate. Moreover, degradations of AFB were strongly affected by the metal ions in which Cu stimulated the degradation and Zn inhibited the degradation. The extracellular detoxifying enzymes produced by co-cultivation of two strains were isolated and purified by ultrafiltration. The molecular weight range of the detoxifying enzymes was 20-25 kDa by SDS-PAGE. The co-culture of two strains improved the total cell growth with the enhancement of the total protein content and detoxifying enzyme production. The degradation efficiency of the supernatant from mixed cultures increased by 87.7% and 55.3% compared to sp. H16v8 and HGD9229, individually. Moreover, after the degradation of AFB, the four products of the lower toxicity were identified by LC-Triple TOF-MS with the two proposed hypothetical degradation pathways.
Topics: Aflatoxin B1; Bacillus; Bacterial Proteins; Biodegradation, Environmental; Coculture Techniques; Endopeptidase K
PubMed: 34206659
DOI: 10.3390/toxins13070435 -
FEMS Microbiology Ecology Jun 2013Bacillus cereus comprises a highly versatile group of bacteria, which are of particular interest because of their capacity to cause disease. Emetic food poisoning is... (Review)
Review
Bacillus cereus comprises a highly versatile group of bacteria, which are of particular interest because of their capacity to cause disease. Emetic food poisoning is caused by the toxin cereulide produced during the growth of emetic B. cereus in food, while diarrhoeal food poisoning is the result of enterotoxin production by viable vegetative B. cereus cells in the small intestine, probably in the mucus layer and/or attached to the host's intestinal epithelium. The numbers of B. cereus causing disease are highly variable, depending on diverse factors linked to the host (age, diet, physiology and immunology), bacteria (cellular form, toxin genes and expression) and food (nutritional composition and meal characteristics). Bacillus cereus group strains show impressive ecological diversity, ranging from their saprophytic life cycle in soil to symbiotic (commensal and mutualistic) lifestyles near plant roots and in guts of insects and mammals to various pathogenic ones in diverse insect and mammalian hosts. During all these different ecological lifestyles, their toxins play important roles ranging from providing competitive advantages within microbial communities to inhibition of specific pathogenic organisms for their host and accomplishment of infections by damaging their host's tissues.
Topics: Animals; Bacillaceae Infections; Bacillus; Bacillus cereus; Bacterial Toxins; Diarrhea; Ecosystem; Emetics; Enterotoxins; Food Microbiology; Foodborne Diseases; Humans; Microbial Interactions; Phylogeny
PubMed: 23488744
DOI: 10.1111/1574-6941.12110 -
Journal of Applied Microbiology Jan 2017To determine the responses of spores of Bacillus subtilis and Bacillus anthracis surrogate Bacillus thuringiensis Al Hakam to I treatment.
AIMS
To determine the responses of spores of Bacillus subtilis and Bacillus anthracis surrogate Bacillus thuringiensis Al Hakam to I treatment.
METHODS AND RESULTS
Spores of B. subtilis and B. thuringiensis killed by aqueous 30°C-I could germinate, and their inner membrane (IM) was intact. Spore coats were important in I resistance, DNA-protective proteins were not important, and survivors of I treatment were not mutagenized. Viabilities of I -treated, 90-98% killed spores were much lower on high-salinity media, and the treated spores were more heat sensitive than the untreated spores. Germinated I -killed spores were dead as determined by staining with nucleic acid dyes, and many appeared to have been lysed.
CONCLUSIONS
Aqueous I appeared to kill B. subtilis and B. thuringiensis spores such that spores lyse soon after they germinate, and not by causing DNA damage or rupture of spores' IM. I treatment also generated many damaged spores that could only be recovered under nonstressful conditions.
SIGNIFICANCE AND IMPACT OF THE STUDY
This work shows that spores of the model organism B. subtilis, and B. thuringiensis, a surrogate for B. anthracis spores, exhibit similar mechanisms of resistance to and killing by I . Generation by I treatment of conditionally dead spores indicates that appropriate media are essential to efficiently enumerate viable I -treated spores.
Topics: Bacillus; Bacillus anthracis; Bacillus subtilis; DNA Damage; Hot Temperature; Iodine; Spores, Bacterial
PubMed: 27696602
DOI: 10.1111/jam.13310 -
Genomics Nov 2020Bacillus sp. SFC 500-1E is used for the effective treatment of tannery effluents since it consistently removes hexavalent chromium from diverse contaminated matrices....
Bacillus sp. SFC 500-1E is used for the effective treatment of tannery effluents since it consistently removes hexavalent chromium from diverse contaminated matrices. The aim of the present study was to complete identification of the strain through a polyphasic characterization, which included the pattern of carbohydrate utilization, fatty acids profile, multilocus sequence analysis, multiplex PCR profile and the analysis of the complete genome sequence. Morpho-physiological and biochemical characterization results and analysis of 16S rRNA sequences were not conclusive. The strain formed a monophyletic clade with B. toyonensis BCT-7112, B. thuringiensis MC28 and B. cereus Rock 1-3. However, genomic comparisons with type strains of B. cereus and B. thuringiensis showed that the isolated belonged to a different species. Results of this study highlight the relevance of the genome sequence of this strain, identified as Bacillus toyonensis SFC 500-1E, to expand knowledge of its bioremediation potential and to explore unknown decontamination activities.
Topics: Bacillus; Bacillus cereus; Biodegradation, Environmental; Genome, Bacterial; Genomics; Phylogeny; RNA, Ribosomal, 16S
PubMed: 32781202
DOI: 10.1016/j.ygeno.2020.08.008 -
Journal of Bacteriology Oct 1967Eight strains of highly amylolytic, sporeforming bacilli (hereafter referred to as Bacillus amyloliquefaciens) were compared with respect to their taxonomic relationship...
Eight strains of highly amylolytic, sporeforming bacilli (hereafter referred to as Bacillus amyloliquefaciens) were compared with respect to their taxonomic relationship to B. subtilis. The physiological-biochemical properties of these two groups of organisms showed that B. amyloliquefaciens differed from B. subtilis by their ability to grow in 10% NaCl, characteristic growth on potato plugs, increased production of alpha-amylase, and their ability to ferment lactose with the production of acid. The base compositions of the deoxyribonucleic acid (DNA) of the B. subtilis strains consistently fell in the range of 41.5 to 43.5% guanine + cytosine (G + C), whereas that of the B. amyloliquefaciens strains was in the 43.5 to 44.9% G + C range. Hybrid formation between B. subtilis W23 and B. amyloliquefaciens F DNA revealed only a 14.7 to 15.4% DNA homology between the two species. Transducing phage, SP-10, was able to propagate on B. subtilis W23 and B. amyloliquefaciens N, and would transduce B. subtilis 168 (indole(-)) and B. amyloliquefaciens N-10 (arginine(-)) to prototrophy with a frequency of 3.9 x 10(-4) and 2.4 x 10(-5) transductants per plaque-forming unit, respectively. Attempts to transduce between the two species were unsuccessful. These data show that Bacillus amyloliquefaciens is a valid species and should not be classified as a strain or variety of B. subtilis.
Topics: Adenine; Amylases; Bacillus; Bacillus subtilis; Culture Media; Cytosine; DNA, Bacterial; Fermentation; Guanine; Hybridization, Genetic; Lactates; Lactose; Mutation; Thymine; Transduction, Genetic; Transformation, Genetic
PubMed: 4963774
DOI: 10.1128/jb.94.4.1124-1130.1967 -
Isolation, selection and evaluation of Bacillus spp. as potential multi-mode probiotics for poultry.The Journal of General and Applied... Sep 2020Bacillus based probiotics are becoming relevant as alternatives to antibiotics used in poultry production and in other animal husbandry. This study describes the...
Bacillus based probiotics are becoming relevant as alternatives to antibiotics used in poultry production and in other animal husbandry. This study describes the isolation of 48 Bacillus spp. candidates, from chickens and chicken environments, for use as potential probiotics in poultry production. These isolates, plus a further 18, were tested in a comprehensive in vitro screening regime that was specifically designed to select the best isolates that satisfied multiple modes of action desirable for commercial poultry probiotics. This screening programme involved the evaluation of the ability of the isolates to survive and grow in the limiting conditions of the chicken gastrointestinal tract. Only 11 of the isolates fulfilled these criteria; hence, they were further evaluated for the ability to adhere to epithelial cells, produce extracellular enzymes, and to demonstrate antagonistic activity against selected pathogens of significant importance in poultry production. Of these, a total of 6 isolates were selected, due to their all-round probiotic capability. Identification by 16S RNA sequencing confirmed these isolates as B. subtilis and B. velezensis, identities which are generally regarded as safe. The Bacillus isolates reported in our study exhibit strong all-inclusive probiotic effects and can potentially be formulated as a probiotic preparation for poultry production.
Topics: Animal Feed; Animals; Bacillus; Bacillus subtilis; Chickens; DNA, Bacterial; Dietary Supplements; Gastrointestinal Tract; Poultry; Probiotics; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 32536637
DOI: 10.2323/jgam.2019.11.002 -
Journal of Microbiology and... Mar 2020Bacteria that are resistant to high temperatures and alkaline environments are essential for the biological repair of damaged concrete. Alkaliphilic and halotolerant...
Bacteria that are resistant to high temperatures and alkaline environments are essential for the biological repair of damaged concrete. Alkaliphilic and halotolerant sp. AK13 was isolated from the rhizosphere of . Unlike other tested species, the AK13 strain grows at pH 13 and withstands 11% (w/v) NaCl. Growth of the AK13 strain at elevated pH without urea promoted calcium carbonate (CaCO) formation. Irregular vateritelike CaCO minerals that were tightly attached to cells were observed using field-emission scanning electron microscopy. Energy-dispersive X-ray spectrometry, confocal laser scanning microscopy, and X-ray diffraction analyses confirmed the presence of CaCO around the cell. Isotope ration mass spectrometry analysis confirmed that the majority of CO ions in the CaCO were produced by cellular respiration rather than being derived from atmospheric carbon dioxide. The minerals produced from calcium acetate-added growth medium formed smaller crystals than those formed in calcium lactate-added medium. Strain AK13 appears to heal cracks on mortar specimens when applied as a pelletized spore powder. Alkaliphilic sp. AK13 is a promising candidate for self-healing agents in concrete.
Topics: Alkalies; Bacillus; Calcium Carbonate; Chemical Precipitation; Genome, Bacterial; Phylogeny
PubMed: 31693829
DOI: 10.4014/jmb.1908.08044 -
Scientific Reports Nov 2017Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a reliable and rapid technique applied widely in the identification and...
Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a reliable and rapid technique applied widely in the identification and classification of microbes. MALDI-TOF MS has been used to identify many endospore-forming Bacillus species; however, endospores affect the identification accuracy when using MALDI-TOF MS because they change the protein composition of samples. Since culture conditions directly influence endospore formation and Bacillus growth, in this study we clarified how culture conditions influence the classification of Bacillus species by using MALDI-TOF MS. We analyzed members of the Bacillus subtilis group and Bacillus cereus group using different incubation periods, temperatures and media. Incubation period was found to affect mass spectra due to endospores which were observed mixing with vegetative cells after 24 hours. Culture temperature also resulted in different mass spectra profiles depending on the temperature best suited growth and sporulation. Conversely, the four common media for Bacillus incubation, Luria-Bertani agar, nutrient agar, plate count agar and brain-heart infusion agar did not result in any significant differences in mass spectra profiles. Profiles in the range m/z 1000-3000 were found to provide additional data to the standard ribosomal peptide/protein region m/z 3000-15000 profiles to enable easier differentiation of some highly similar species and the identification of new strains under fresh culture conditions. In summary, control of culture conditions is vital for Bacillus identification and classification by MALDI-TOF MS.
Topics: Bacillus; Bacterial Proteins; Bacterial Typing Techniques; Culture Media; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Spores, Bacterial
PubMed: 29138467
DOI: 10.1038/s41598-017-15808-5 -
Journal of Bacteriology Nov 1972Changes in the endogenous intracellular amino acid pool and total free amino acid production in Bacillus licheniformis grown in minimal media were investigated. The...
Changes in the endogenous intracellular amino acid pool and total free amino acid production in Bacillus licheniformis grown in minimal media were investigated. The total intracellular pool increased during exponential growth and then decreased rapidly after the end of growth. Most of the amino acids were present at low concentrations, but glutamate and alanine comprised 60 to 90% of the total intracellular free amino acid at most times during the growth cycle. It was concluded that, in addition to providing monomers for protein synthesis, the intracellular amino acid pool may be maintained for the storage of energy-providing metabolic intermediates and possibly as a balance to the ionic strength of the medium. The total free amino acid production by the cell was found to be dependent upon the composition of the salts medium as well as the culture age under conditions in which the carbon and nitrogen sources were the same. A 10-fold increase in extracellular amino acid was observed as the cells changed from vegetative to sporulation metabolism, mostly due to the extrusion of intracellular amino acid. The impact of this increase upon amino acid uptake and pulse-labeling studies using unwashed cells is discussed.
Topics: Alanine; Amino Acids; Autoanalysis; Bacillus; Bacterial Proteins; Culture Media; Glucose; Glutamates; Micropore Filters; Spores, Bacterial; Time Factors
PubMed: 5086658
DOI: 10.1128/jb.112.2.715-725.1972 -
Scientific Reports Jan 2023Monitoring the presence of pathogenic Bacillus spores is important for industrial applications, as well as necessary for ensuring human health. Bacillus thuringiensis is...
Monitoring the presence of pathogenic Bacillus spores is important for industrial applications, as well as necessary for ensuring human health. Bacillus thuringiensis is used as a biopesticide against several insect pests. Bacillus cereus spores are a significant cause of food poisoning, and Bacillus anthracis is a recognized biosecurity threat. Laboratory-based methods, such as polymerase chain reaction, enzyme-linked immunosorbent assay, or matrix-assisted laser desorption ionization spectroscopy provide sensitive detection of bacteria and spores, but the application of those methods for quasi-continuous environmental monitoring presents a significant challenge requiring frequent human intervention. To address this challenge, we developed a workstation for quasi-autonomous monitoring of water reservoirs for the presence of bacteria and spores, and designed and validated the functionality of a microprocessor-controlled module capable of repetitive collection and pre-concentration of spores in liquid samples tested with fiberglass (FG), polyether sulfone and polyvinylidene fluoride filters. The best results were obtained with FG filters delivering a 20× concentration of B. thuringiensis and B. cereus spores from saline suspensions. The successful 20× pre-concentration of Bacillus spores demonstrated with FG filters could be repeated up to 3 times when bleach decontamination is applied between filtrations. Taken together, our results demonstrate an attractive instrument suitable for semi-automated, quasi-continuous sampling and pre-processing of water samples for biosensing of bacterial spores originating from a complex environment.
Topics: Humans; Bacillus; Bacillus cereus; Bacillus anthracis; Spores, Bacterial; Bacillus thuringiensis
PubMed: 36646757
DOI: 10.1038/s41598-023-27900-0