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Journal of Applied Microbiology Sep 2011To determine the effects of Mn levels in Bacillus megaterium sporulation and spores on spore resistance.
AIMS
To determine the effects of Mn levels in Bacillus megaterium sporulation and spores on spore resistance.
METHODS AND RESULTS
Bacillus megaterium was sporulated with no added MnCl(2) and up to 1 mmol l(-1) MnCl(2). The resultant spores were purified and loosely bound Mn removed, and spore Mn levels were found to vary c. 100-fold. The Mn level had no effect on spore γ-radiation resistance, but B. megaterium spores with elevated Mn levels had higher resistance to UVC radiation (as did Bacillus subtilis spores), wet and dry heat and H(2)O(2). However, levels of dipicolinic acid and the DNA-protective α/β-type small, acid-soluble spore proteins were the same in spores with high and low Mn levels.
CONCLUSIONS
Mn levels either in sporulation or in spores are important factors in determining levels of B. megaterium spore resistance to many agents, with the exception of γ-radiation.
SIGNIFICANCE AND IMPACT OF THE STUDY
The Mn level in sporulation is an important factor to consider when resistance properties of B. megaterium spores are examined, and will influence the UV resistance of B. subtilis spores, some of which are used as biological dosimeters.
Topics: Bacillus megaterium; Bacillus subtilis; Bacterial Proteins; Gamma Rays; Hot Temperature; Hydrogen Peroxide; Manganese; Picolinic Acids; Spores, Bacterial; Ultraviolet Rays
PubMed: 21714839
DOI: 10.1111/j.1365-2672.2011.05095.x -
Applied and Environmental Microbiology Oct 2018The exosporium of QM B1551 spores is morphologically distinct from exosporia observed for the spores of many other species. Previous work has demonstrated that...
The exosporium of QM B1551 spores is morphologically distinct from exosporia observed for the spores of many other species. Previous work has demonstrated that unidentified genes carried on one of the large indigenous plasmids are required for the assembly of the exosporium. Here, we provide evidence that pBM600-encoded orthologues of the CotW and CotX proteins, which form the crust layer in spores of that species, are structural components of the QM B1551 spore exosporium. The introduction of plasmid-borne and orthologous genes to the PV361 strain, which lacks all indigenous plasmids and produces spores that are devoid of an exosporium, results in the development of spores with a rudimentary exosporium-type structure. Additionally, purified recombinant CotW protein is shown to assemble at the air-water interface to form thin sheets of material, which is consistent with the idea that this protein may form a basal layer in the QM B1551 exosporium. When starved of nutrients, some bacterial species develop metabolically dormant spores that can persist in a viable state in the environment for several years. The outermost layers of spores are of particular interest since (i) these represent the primary site for interaction with the environment and (ii) the protein constituents may have biotechnological applications. The outermost layer, or exosporium, in QM B1551 spores is of interest, as it is morphologically distinct from the exosporia of spores of the pathogenic family. In this work, we provide evidence that structurally important protein constituents of the exosporium are different from those in the family. We also show that one of these proteins, when purified, can assemble to form sheets of exosporium-like material. This is significant, as it indicates that spore-forming bacteria employ different proteins and mechanisms of assembly to construct their external layers.
Topics: Bacillus megaterium; Bacillus subtilis; Bacterial Proteins; Mutation; Plasmids; Spores, Bacterial
PubMed: 30097448
DOI: 10.1128/AEM.01734-18 -
Microbiology (Reading, England) Jun 2020A range of bacteria and archaea produce gas vesicles as a means to facilitate flotation. These gas vesicles have been purified from a number of species and their... (Review)
Review
A range of bacteria and archaea produce gas vesicles as a means to facilitate flotation. These gas vesicles have been purified from a number of species and their applications in biotechnology and medicine are reviewed here. sp. NRC-1 gas vesicles have been engineered to display antigens from eukaryotic, bacterial and viral pathogens. The ability of these recombinant nanoparticles to generate an immune response has been quantified both and . These gas vesicles, along with those purified from and , have been developed as an acoustic reporter system. This system utilizes the ability of gas vesicles to retain gas within a stable, rigid structure to produce contrast upon exposure to ultrasound. The susceptibility of gas vesicles to collapse when exposed to excess pressure has also been proposed as a biocontrol mechanism to disperse cyanobacterial blooms, providing an environmental function for these structures.
Topics: Animals; Bacillus megaterium; Biotechnology; Environment; Gases; Halobacterium; Humans; Medicine; Nanotechnology; Organelles
PubMed: 32324529
DOI: 10.1099/mic.0.000912 -
Anais Da Academia Brasileira de Ciencias 2019The strains CM-Z19 and CM-Z6, which are capable of highly degrading chlorpyrifos-methyl, were isolated from soil. They were identified as Bacillus megaterium CM-Z19 and...
The strains CM-Z19 and CM-Z6, which are capable of highly degrading chlorpyrifos-methyl, were isolated from soil. They were identified as Bacillus megaterium CM-Z19 and Pseudomonas syringae CM-Z6, respectively, based on the 16S rRNA and an analysis of their morphological, physiological and biochemical characteristics. The strain CM-Z19 showed 92.6% degradation of chlorpyrifos-methyl (100 mg/L) within 5 days of incubation, and the strain CM-Z6 was 99.1% under the same conditions. In addition, the degradation characteristics of the two strains were compared and studied, and the results showed that the strain CM-Z19 had higher phosphoesterase activity and ability to degrade the organophosphorus pesticide than did the strain CM-Z6. However, the strain CM-Z19 could not degrade its first hydrolysis metabolite 3,5,6-trichloro-2-pyridinol (TCP) and could not completely degrade chlorpyrifos-methyl. The strain CM-Z6 could effectively degrade TCP and could degrade chlorpyrifos-methyl more quickly than strain CM-Z19.
Topics: Bacillus megaterium; Biodegradation, Environmental; Chlorpyrifos; Insecticides; Pesticides; Pseudomonas syringae; RNA, Ribosomal, 16S; Soil Microbiology
PubMed: 31618412
DOI: 10.1590/0001-3765201920180694 -
Bioengineered Dec 2021High production costs still hamper fast expansion of commercial production of polyhydroxyalkanoates (PHAs). This problem is greatly related to the cultivation medium...
High production costs still hamper fast expansion of commercial production of polyhydroxyalkanoates (PHAs). This problem is greatly related to the cultivation medium which accounts for up to 50% of the whole process costs. The aim of this research work was to evaluate the potential of using volatile fatty acids (VFAs), derived from acidogenic fermentation of food waste, as inexpensive carbon sources for the production of PHAs through bacterial cultivation. could assimilate glucose, acetic acid, butyric acid, and caproic acid as single carbon sources in synthetic medium with maximum PHAs production yields of 9-11%, on a cell dry weight basis. Single carbon sources were then replaced by a mixture of synthetic VFAs and by a VFAs-rich stream from the acidogenic fermentation of food waste. After 72 h of cultivation, the VFAs were almost fully consumed by the bacterium in both media and PHAs production yields of 9-10%, on cell dry weight basis, were obtained. The usage of VFAs mixture was found to be beneficial for the bacterial growth that tackled the inhibition of propionic acid, iso-butyric acid, and valeric acid when these volatile fatty acids were used as single carbon sources. The extracted PHAs were revealed to be polyhydroxybutyrate (PHB) by characterization methods of Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The obtained results proved the possibility of using VFAs from acidogenic fermentation of food waste as a cheap substrate to reduce the cost of PHAs production.
Topics: Acids; Bacillus megaterium; Biomass; Calorimetry, Differential Scanning; Fatty Acids, Volatile; Fermentation; Food; Glucose; Hydrogen-Ion Concentration; Polyhydroxyalkanoates; Refuse Disposal; Spectroscopy, Fourier Transform Infrared
PubMed: 34115556
DOI: 10.1080/21655979.2021.1935524 -
Manually curated genome-scale reconstruction of the metabolic network of Bacillus megaterium DSM319.Scientific Reports Dec 2019Bacillus megaterium is a microorganism widely used in industrial biotechnology for production of enzymes and recombinant proteins, as well as in bioleaching processes....
Bacillus megaterium is a microorganism widely used in industrial biotechnology for production of enzymes and recombinant proteins, as well as in bioleaching processes. Precise understanding of its metabolism is essential for designing engineering strategies to further optimize B. megaterium for biotechnology applications. Here, we present a genome-scale metabolic model for B. megaterium DSM319, iJA1121, which is a result of a metabolic network reconciliation process. The model includes 1709 reactions, 1349 metabolites, and 1121 genes. Based on multiple-genome alignments and available genome-scale metabolic models for other Bacillus species, we constructed a draft network using an automated approach followed by manual curation. The refinements were performed using a gap-filling process. Constraint-based modeling was used to scrutinize network features. Phenotyping assays were performed in order to validate the growth behavior of the model using different substrates. To verify the model accuracy, experimental data reported in the literature (growth behavior patterns, metabolite production capabilities, metabolic flux analysis using C glucose and formaldehyde inhibitory effect) were confronted with model predictions. This indicated a very good agreement between in silico results and experimental data. For example, our in silico study of fatty acid biosynthesis and lipid accumulation in B. megaterium highlighted the importance of adopting appropriate carbon sources for fermentation purposes. We conclude that the genome-scale metabolic model iJA1121 represents a useful tool for systems analysis and furthers our understanding of the metabolism of B. megaterium.
Topics: Bacillus megaterium; Fatty Acids; Feasibility Studies; Genome, Bacterial; Genomics; Industrial Microbiology; Lipid Metabolism; Metabolic Engineering; Metabolic Networks and Pathways; Metabolomics; Models, Biological
PubMed: 31822710
DOI: 10.1038/s41598-019-55041-w -
Journal of Bacteriology Aug 1983Megacins A-216 and A-19213 in Bacillus megaterium are plasmid encoded, as shown by analysis of cured, non-megacinogenic (Meg-) derivatives of strains 216 and ATCC 19213...
Megacins A-216 and A-19213 in Bacillus megaterium are plasmid encoded, as shown by analysis of cured, non-megacinogenic (Meg-) derivatives of strains 216 and ATCC 19213 and by polyethylene glycol-mediated protoplast transformation of Meg- bacteria with plasmid DNA. The results of both techniques implicated a 31-megadalton plasmid, pBM309, in megacin A-216 production and a 29-megadalton plasmid, pBM113, in megacin A-19213 production.
Topics: Bacillus megaterium; Bacteriocins; DNA, Bacterial; Immunodiffusion; Megacins; Mutation; Plasmids; Propylene Glycols; Protoplasts; Transformation, Genetic
PubMed: 6409886
DOI: 10.1128/jb.155.2.872-877.1983 -
Journal of Agricultural and Food... Apr 2020Squalene synthase (SQS) catalyzes the conversion of two farnesyl pyrophosphates to squalene, an important intermediate in between isoprene and valuable triterpenoids. In...
Squalene synthase (SQS) catalyzes the conversion of two farnesyl pyrophosphates to squalene, an important intermediate in between isoprene and valuable triterpenoids. In this study, we have constructed a novel biosynthesis pathway for squalene in and performed metabolic engineering aiming at facilitating further exploitation and production of squalene-derived triterpenoids. Therefore, systematic studies and analysis were performed including selection of multiple SQS candidates from various organisms, comparison of expression vectors, optimization of cultivation temperatures, and examination of rate-limiting factors within the synthetic pathway. We were, for the first time, able to obtain squalene synthesis in . Furthermore, we achieved a 29-fold increase of squalene yield (0.26-7.5 mg/L) by expressing SQS from and eliminating bottlenecks within the upstream methylerythritol-phosphate pathway. Moreover, our findings showed that also could positively affect the production of squalene.
Topics: Bacillus megaterium; Bacillus subtilis; Bacterial Proteins; Farnesyl-Diphosphate Farnesyltransferase; Metabolic Engineering; Squalene
PubMed: 32208656
DOI: 10.1021/acs.jafc.0c00375 -
International Journal of Biological... Jun 2018Poly-[(R)-3-hydroxybutyrate] (PHB) films prepared by compression molding and solvent casting, respectively, were degraded with the intracellular depolymerase enzyme...
Poly-[(R)-3-hydroxybutyrate] (PHB) films prepared by compression molding and solvent casting, respectively, were degraded with the intracellular depolymerase enzyme natively synthetized by the strain Bacillus megaterium. Quantitative analysis proved that practically only (R)-3-hydroxybutyric acid (3-HBA) forms in the enzyme catalyzed reaction, the amount of other metabolites or side products is negligible. The purity of the product was verified by several methods (UV-VIS spectroscopy, liquid chromatography, mass spectroscopy). Degradation was followed as a function of time to determine the rate of enzymatic degradation. Based on the Michaelis-Menten equation a completely new kinetic model has been derived which takes into consideration the heterogeneous nature of the enzymatic reaction. Degradation proceeds in two steps, the adsorption of the enzyme onto the surface of the PHB film and the subsequent degradation reaction. The rate of both steps depend on the preparation method of the samples, degradation proceed almost twice as fast in compression molded films than in solvent cast samples. The model can describe and predict the formation of the reaction product as a function of time. The approach can be used even for the commercial production of 3-HBA, the chemical synthesis of which is complicated and expensive.
Topics: Adsorption; Bacillus megaterium; Carboxylic Ester Hydrolases; Catalysis; Hydrolysis; Hydroxybutyrates; Kinetics; Polyesters
PubMed: 29414726
DOI: 10.1016/j.ijbiomac.2018.01.104 -
Journal of Bacteriology Jan 1975Bacillus megaterium grows in a medium containing L-tryptophan as the sole carbon, nitrogen, and energy source. Kynurenine, anthranilic acid, and catechol are metabolic...
Bacillus megaterium grows in a medium containing L-tryptophan as the sole carbon, nitrogen, and energy source. Kynurenine, anthranilic acid, and catechol are metabolic intermediates, suggesting that this organism used the anthranilic acid pathway for tryptophan degradation. Cells that grow on L-tryptophan oxidize kynurenine, alanine, and anthranilic acid and the presence of tryptophan oxygenase (EC 1.13.1.12), kynureninase (EC 3.7.1.3), and catechol oxygenase (EC 1.13.1.1) in cell extracts provide additional evidence for the degradative pathway in B. megaterium. Tryptophan oxygenase is inhibited by sodium azide, potassium cyanide, and hydroxylamine, indicating that the enzyme has a functional heme group. D-Tryptophan is not a substrate for tryptophan oxygenase, and the D-isomer does not inhibit this enzyme. Formamidase (EC 3.5.1.9) and anthranilate hydroxylase are not detectable in extracts. Tryptophan catabolism is inducible in B megaterium and is subject to catabolite repression by glucose and glutamate. Arginine does not cause repression, and kynurenine induces both tryptophan oxygenase and kynureninase.
Topics: Alanine; Arginine; Bacillus megaterium; Catechols; Cell-Free System; Enzyme Induction; Enzyme Repression; Glucose; Hydrolases; Kynurenine; Oxidation-Reduction; Oxygen Consumption; Oxygenases; Tryptophan; ortho-Aminobenzoates
PubMed: 803956
DOI: 10.1128/jb.121.1.70-76.1975