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1.
Summary In an attempt to screen for air flora producing new potent antimicrobial substances, Bacillus megaterium NB-3, Bacillus cereus NB-4, Bacillus cereus NB-5, Bacillus subtilis NB-6 and Bacillus circulans NB-7, were isolated and were found to be antagonistic to bacteria and/or fungi. Production of antimicrobial substances by the bacterial strains was greatly influenced by variation of carbon sources. Glycerol strongly enhanced the antimicrobial activity of strains NB-3 and NB-6, whereas glucose increased the antimicrobial activity of strains NB-4 and NB-5. The maximum antibiotic yield of NB-7 was achieved with fructose as a carbon source. Starch (Bacillus megaterium NB-3), maltose (Bacillus cereus NB-5), glycerol (Bacillus circulans NB-7), arabinose, ribose (Bacillus cereus NB-4) and arabinose, fructose, glucose, ribose and sucrose (Bacillus subtilis NB-6) repressed the production of antimicrobial substances by the respective bacterial strains.  相似文献   

2.
The products of several Bacillus strains were investigated on rabbit serum calcium decreasing, oxytocic and toad heart function promoting activities. These products were obtained from the clear supernatant fluid of the culture medium after the cells were removed by centrifugation.

For the production of rabbit serum calcium decreasing substance, Bacillus subtilis K and Bacillus natto No. 8 were found to be usefull, Bacillus megaterium KM, Bacillus cereus var. mycoides and Bacillus subtilis K produced oxytocic principle. Bacillus subtilis K, Bacillus brevis and Bacillus megaterium KM also produced toad heart function promoting factor.

A procedure was developed to obtain the electrophoretically homogenous rabbit serum calcium decreasing substance from culture filtrate of Bacillus subtilis K. The crude substance was obtained as isoelectric precipitate by adjusting the culture filtrate to pH 3.0. The crude substance was purified by gel filtration on a Sephadex G-75 column, isoelectric fractionation and chromatography on DEAE-cellulose column. The purified preparation was shown to be homogenous by Tiselius electrophoresis but was separated into two bands by polyacrylamide electrophoresis. The chemical analysis of this biologically active substance indicated this substance to be a lipoprotein. The substance decreased rabbit serum calcium level about 12% at 6~8hr after intravenous injection (dose; 0.5 mg/kg body weight).  相似文献   

3.
Abstract

In this study, bacteria were isolated from two different magnesite quarries in Turanocak and Ortaocak mine in Kütahya-Eski?ehir region, one of the largest processed magnesite reserves in Turkey. The obtained isolates have a potential to solve important magnesite pollutant CaCO3 but incapable to solve magnesium that has the most crucial role in the industry. Thus, potential bacteria were identified to be used for magnesite enrichment studies. The obtained isolates were identified and characterized according to the morphological, physiological, biochemical, and molecular techniques (16S rDNA PCR). According to the gene sequencing analysis Bacillus genus bacteria have the ability to solve CaCO3. The data of the 16S rDNA gene sequence showed that there were 13 active strains grouped in Bacillus. These active strains; Bacillus sp (3), Bacillus atrophaeus (2), Bacillus thuringiensis (1), Bacillus circulans (1), Bacillus simplex (3), Bacillus endophyticus (1) Bacillus drentensis (1) and Bacillus idriensis (1).  相似文献   

4.
New isolates of spore-forming bacilli from larvae and pupae of 3 species of mosquitoes are recorded in central Iraq.Bacillus sphaericus Meyer and Neide was isolated fromCulex pipiens (L.) larva.Bacillus carotarum Koch andBacillus cereus Frankland & Frankland were isolated fromTheobaldia longiareolata (Macquart) pupae.Bacillus laterosporus Laubach andBacillus thuringiensis (H 18) were isolated fromAedes caspius (Pallas) larvae. In addition, unidentifiedBacillus spp. were isolated fromCx. pipiens, T. longiareolata andAe. caspius larvae. Examination of soil samples collected from mosquito natural breeding habitats revealed isolates ofB. cereus, Bacillus thuringiensis H4a 4b; H 12 and H 16 and an unidentifiedBacillus sp.
Résumé Des souches bactériennes sporogènes sont isolées de moustiques qui se trouvent dans la région centrale de l'Irak. Les résultats obtenus sont les suivants:Bacillus sphaericus Meyer & Neide [Culex pipiens (L.), larve],Bacillus carotarum Koch etBacillus cereus Frankland & Frankland [Theobaldia longiareolata (Macquart), nymphe],Bacillus laterosporus Laubach etBacillus thuringiensis (H 18) [Aedes caspius (Pallas), larvel]. L'examen des larves deCulex pipiens. T. longiareolata etAe. caspius, ainsi que l'analyse des échantillons du sol prélevés dans la région montrent la présence deBacillus cereus, Bacillus thuringiensis H4a 4b; H12 plus H16 et d'autresBacillus non identifiés.
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5.
Aims: To survey paperboard products from 17 US mills for bacterial populations and for bacteria potentially harmful to human health. Methods and Results: Culturable aerobic bacteria were isolated from paperboard products using selective and nonselective medium. Resulting colonies from samples from three regions of the United States were identified using fatty acid methyl ester analysis. Percentages of bacteria species found were Bacillus megaterium (47), Bacillus licheniformis (15), Bacillus pumilus (12), Paenibacillus macerans (5), Paenibacillus pabuli (3), Bacillus subtilis (2), Bacillus cereus (2), Bacillus coagulans (1), Bacillus circulans (1), Bacillus brevis (1), Bacillus thuringiensis (1), Paenibacillus polymyxa (1), Cellulomonas turbata (1), Cellulomonas flavigena (1), unidentified Bacillus sp. (3) and unidentified bacteria (1). Conclusions: Recycled paperboard contained high populations of bacteria, and a positive correlation was found between recycle content and bacterial populations. Escherichia coli, Salmonella, Shigella or confirmed coliform bacteria were not found in any product. Significance and Impact of the Study: Populations of bacteria did not differ significantly from original counts over a 4‐month period of dry storage, indicating that bacteria persist in paperboard over long periods and may re‐enter the recycling process. The predominance of heat‐tolerant endospore‐forming bacteria explains the high bacteria counts found in paperboard made from recycled materials .  相似文献   

6.
The D95°C value of Bacillus thuringiensis spores plated in the presence of lysozyme increased from 3.0 min to 3.6 min by post-treatment of heat-injured spores with 50mm EDTA. In the case of Bacillus alvei and Bacillus polymyxa spores D-values decreased from 4.9 to 4.3 min and from 4.7 to 4.1 min respectively. Post-treatment of heat-injured spores treated with alkaline thioglycollate increased D95°C values of Bacillus alvei from 4.2 to 5.3 min, B. thuringiensis 3.6 to 4.7 min, and Bacillus polymyxa from 4.2 to 5.0 min when spores were plated in the presence of lysozyme. Electron micrographs of heat-injured B. alvei spores treated with sodium thioglycollate indicated that the coat layers of the treated spores were granulated and less intact than the control spores.  相似文献   

7.
In order to obtain the diversity and temporal–spatial distribution of Bacillus community during the swine manure composting, we utilized traditional culture methods and the modern molecular biology techniques of polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) and –denaturing gradient gel electrophoresis (PCR-DGGE). Bacillus species were firstly isolated from the composting. Based on temperature changes, the temporal–spatial characteristics of total culturable Bacillus were remarkable that the number of the culturable Bacillus detected at the high-temperature stage was the highest in each layer of the pile and that detected in the middle layer was the lowest at each stage of composting respectively. The diversity of cultivated Bacillus species isolated from different composting stages was low. A total of 540 isolates were classified by the RFLP method and partial 16S rDNA sequences. They affiliated to eight species including Bacillus subtilis, Bacillus cereus, Bacillus thuringiensis, Bacillus anthracis, Bacillus megaterium, Bacillus licheniformis, Bacillus pumilus, and Bacillus circulans. The predominant species was B. subtilis, and the diversity of culturable Bacillus isolated in the middle-level samples at temperature rising and cooling stages was the highest. The DGGE profile and clone library analysis revealed that the temporal–spatial distribution of Bacillus community was not obvious, species belonging to the Bacillus were dominant (67%) with unculturable bacteria and B. cereus was the second major culturable Bacillus species. This study indicated that a combination of culture and culture-independent approaches could be very useful for monitoring the diversity and temporal–spatial distribution of Bacillus community during the composting process.  相似文献   

8.
Nine strains of bacteria, capable of synthesising amino acids from hydrocarbons, have been identified. Pseudomonas arvilla, Ps. fluorescens and Micrococcus ureae, previously reported as hydrocarbons assimilators, were found capable of synthesising amino acids. Pseudomonas taetrolens, Bacillus cereus var. mycoides, Bacillus subtilis and Bacillus sphaericus also synthesised amino acids from hydrocarbons.  相似文献   

9.
Summary Polyhydroxyalkanoates (PHAs) are polyesters of hydroxyalkanoates synthesized by numerous bacteria as intracellular carbon and energy storage compounds and accumulated as granules in the cytoplasm of cells. In this work, we constructed two recombinant plasmids, pBE2C1 and pBE2C1AB. The two plasmids were inserted into Bacillus subtilis DB104 and generated Bacillus subtilis/pBE2C1 and Bacillus subtilis/pBE2C1AB. The two recombinant strains were subjected to fermentation and showed PHA accumulation, the first reported example of medium-chain-length-PHA production in Bacillus subtilis. GC analysis identified the compound produced by Bacillus subtilis/pBE2C1 was a hydroxydecanoate-co-hydroxydodecanoate (HD-co-HDD) polymer while that produced by Bacillus subtilis/pBE2C1AB was a hydroxybutyrate-co-hydroxydecanoate-co-hydroxydodecanoate (HB-HD-HDD) polymer. The results also showed that the recombinant B. subtilis could utilize the malt waste in the medium as a carbon source better than that of glucose and thus could substantially lower the cost of production of PHA.  相似文献   

10.
Two Bacillus thuringiensis strains isolated from diseased Spodoptera frugiperda larvae collected in the northwest of Argentina were molecularly and phenotypically characterized. Insecticidal activity against Spodoptera frugiperda larvae was also determined. Both strains were highly toxic against first instar larvae. One strain (Bacillus thuringiensis LSM) was found to be even more toxic than the reference strain Bacillus thuringiensis var. kurstaki 4D1. This strong biological effect was represented by both a higher mortality which reached 90%, and a shorter LT50. Molecular characterization showed that Bacillus thuringiensis LSM carried a cry gene profile identical to that of Bacillus thuringiensis var. kurstaki 4D1. Evaluation of length polymorphism of the intergenic transcribed spacers between the 16S and 23S rDNA genes revealed an identical pattern between native strains and Bacillus thuringiensis var. kurstaki 4D1. In contrast, phenotypic characterization allowed differentiation among the isolates by means of their extracellular esterase profiles. Lytic activity that would contribute to Bacillus thuringiensis effectiveness was also studied in both strains. Analyses like those presented in the current study are essential to identify the most toxic strains and to allow the exploitation of local biodiversity for its application in biological control programmes.  相似文献   

11.
The Bacillus subtilis wild strains isolated from okpehe, a traditional fermented condiment used as seasoning in Nigeria, the reference and typed strains were investigated for their phenotypic diversity and their technological parameters with a view to obtain adequate data that would enable selection of appropriated starter cultures for vegetable protein fermentation in West Africa. All the 7 strains studied demonstrated diverse phenotypic characteristics and they were identified as Bacillus subtilis, based on the API 50 CHB combined with API 20E profile. Specific sugars that indicated a good hydrolytic potential of the wild strains were fermented. The highest proteinase activity of 90 AU/ml determined quantitatively was observed in the strain Bacillus subtilis BFE 5372, the proteinase was identified by the APIZYM gallery as chymotrypsin. Highest amylase activity of 13 AU/ml was noticed in strain Bacillus subtilis DSM 347 while only 4 strains produced polyglutamic acid with the strain Bacillus subtilis BFE 5359 producing the highest polyglutamate activity of 2.5 mm. Although strain Bacillus subtilis BFE 5301 did not release detectable polyglutamate, the strain demonstrated antagonism against different bacteria and the antimicrobial substance produced by strain Bacillus subtilis BFE 5301 was confirmed as a bacteriocin since its activities were lost after treatment with chymotrypsin and pepsin. The data generated showed the technological parameters that can aid selection of wild strains such as Bacillus subtilis BFE 5301, BFE 5359 and BFE 5372 for optimization of condiment production.  相似文献   

12.
A total of thirty-three strains of Bacillus were isolated from sixteen samples of naturally fermented congee in Inner Mongolia of China and identified by 16S rDNA sequence analysis. Probiotic properties including acid, bile tolerance and artificial gastrointestinal juice resistance as well as inhibition on pathogenic bacteria were used for screening of Bacillus. After the preliminary selection, four strains including Bacillus licheniformis IMAUB1002, Bacillus subtilis IMAUB1011, Bacillus amyloliquefaciens IMAUB1014 and Bacillus amyloliquefaciens IMAUB1034 showed high tolerance to simulated gastric juice at pH 2.0 for 3 h with survival rate all above 92%. And then through gastrointestinal transit, survival rates of these four strains were above 90%. Furthermore, Bacillus licheniformis IMAUB1002 performed well in tolerance to bile salt (0.6%) and inhibitory activity to five food-borne pathogens among four strains of Bacillus. The results suggested that Bacillus licheniformis IMAUB1002 should be considered as a potential probiotics. Further study will be focused on evaluation of these porbiotics properties in vivo and clarification of its other functional properties so as to use it in functional foods production in future.  相似文献   

13.
Marine bacteria from the hull of a ship in the form of biofilms or microfouling were isolated, cultured, and identified by phylogenetic analysis using 16S rDNA sequences. With an average length of 946 bp, all the 16 sequences were classified using the Ribosomal database project (RDP) and were submitted to the National Center for Biotechnology Information. Phylogenetic analysis using 16S rDNA sequences indicated that the 16 strains belonged to the Firmicutes (IK-MB6 Exiguobacterium aurantiacum, IK-MB7 Exiguobacterium arabatum, IK-MB8 Exiguobacterium arabatum, IK-MB9 Jeotgalibacillus alimentarius, IK-MB10 Bacillus megaterium, IK-MB11 Bacillus pumilus, IK-MB12 Bacillus pumilus, IK-MB13 Bacillus pumilus, IK-MB14 Bacillus megaterium), High GC, Gram-positive bacteria (IK-MB2 Micrococcus luteus, IK-MB5 Micrococcus luteus, IK-MB16 Arthrobacter mysorens), G-Proteobacteria (IK-MB3 Halomonas aquamarina, IK-MB15 Halotalea alkalilenta), CFB group bacteria (IK-MB1 Myroides odoratimimus), and Enterobacteria (IK-MB4 Proteus mirabilis). Among the 16 strains, representatives of the Firmicutes were dominant (56.25%) compared to the high GC, Gram-positive bacteria (18.75%), G-Proteobacteria (12.5%), CFB group bacteria (6.25%), and Enterobacteria (6.25%). Analysis revealed that majority of marine species found in marine biofilm are of anthropogenic origin.  相似文献   

14.
Aims: To investigate the ability of bacilli of various species (Bacillus clausii, Bacillus subtilis, Bacillus lentus, Bacillus pumilus. Bacillus megaterium, Bacillus firmus, Bacillus sp.) and origins (probiotic and collection strains) to counteract the activity of some representative DNA‐reactive agents. Methods and Results: The inhibitory effect of 21 bacilli strains, previously characterized by tDNA‐PCR, on four genotoxins, was examined in vitro using the short‐term assay SOS‐Chromotest. All strains had a high inhibitory activity against 4‐nitroquinoline‐1‐oxide and N‐methyl‐N′‐nitro‐nitrosoguanidine (direct agents), whereas the inhibitory activity was high or moderate against 2‐amino‐3,4‐dimethylimidazo[4,5‐f]quinoline and aflatoxin B1 (indirect agents). Antigenotoxicity was observed in vegetative cells, but not heat‐treated cells or spore suspensions. The spectroscopic properties of compounds were modified after cell co‐incubation and all the strains maintained high viability after exposure to the genotoxins. Conclusions: No relevant differences in antigenotoxicity were evidenced among strains of the examined species or between probiotic and collection strains. Significance and Impact of the Study: Although derived from an in vitro model, the results suggest that Bacillus‐based probiotics could be useful for reducing the gastrointestinal risk originating from genotoxic agents.  相似文献   

15.
Cell free extracts prepared from exponentially growing Escherichia coli and Bacillus cereus as well as from Bacillus cereus at the end of exponential growth were optimized for various factors required for amino acid incorporation when programmed with Bacillus ribonucleic acid. All three preparations synthesized glutamine synthetase antigen when ribonucleic acid from a Bacillus subtilis strain that overproduces glutamine synthetase was added. The post exponential Bacillus cereus extract, however, was most active for the synthesis of Bacillus cereus spore coat antigen when supplemented with the appropriate ribonucleic acid. There appears to be some specificity in the translation of at least this sporulation messenger RNA.Non-Standard Abbreviations PMSF phenyl methyl sulfonylfluoride - GS glutamine synthetase - UDS 8 M urea, 1% (W/V) sodium dodecyl sulfate, 50 mM dithioerythritol, 2 mM PMSF, 5 mM cyclohexylaminoethane sulfonic acid, pH 9.6  相似文献   

16.
The main purpose of the study was to isolate strains of bacteria capable of degrading hydrocarbons from contaminated mangroves and to investigate the ability of the isolated bacteria to degrade total petroleum hydrocarbons (TPH) in a microcosm model of an oily sludge. The potential use of these bacteria strains as environmental clean-up agents was tested by culturing them with six different polyaromatic hydrocarbon (PAH) compounds (phenothiazine, fluorene, fluoranthene, dibenzothiophene, phenanthrene, and pyrene). Six viable and culturable bacteria were isolated, and the 16S rDNA sequence for each was amplified using the primers 9F and 1510R. Sequence results were compared using the National Center for Biotechnology Information (NCBI) BLAST program and, combined with phenotypic and phylogenetic data, were used to identify three strains that belonged to the Bacillus genus and were most closely related (98–99%) to Bacillus aquimaris, Bacillus megaterium, and Bacillus pumilus. The other three strains were closely related (98–100%) to Flexibacteraceae bacterium, Halobacilus trueperi, and Rhodobacteraceae bacterium. Two isolates, BA-PZN and BM-PFFP, which were related to Bacillus aquimaris and Bacillus megaterium, respectively, were further characterized and showed great potential for the removal of more complex hydrocarbon compounds in the oily microcosm model.  相似文献   

17.
The expression of parasporal crystal protein (δ-endotoxin) coding gene(s) ofBacillus thuringlensis var.israelensis and its association, if any, with sporulation was studied in sporogenicBacillus cereus and its asporogenic mutant strains. Five asporogenous mutants ofBacillus cereus blocked at different stages of sporulation, were isolated from a streptomycin-resistant strain, The transconjugants isolated from the plasmid transfer experiments betweenBacillus thuringiensis var.israelensis and streptomycin resistantBacillus cereus and its asporogenous mutants, showed larvicidal activity. The crystal protein gene(s) are, therefore, expressed both in sporulating and in non-sporulating mutant strains ofBacillus cereus suggesting that the expression of crystal protein gene(s), is independent of sporulation specific functions inBacillus cereus. Part of the work was carried out at Biotechnology Programme, Jadavpur University, Calcutta 700 032, India.  相似文献   

18.
A Gram-positive, rod-shaped, endospore-forming organism, strain BL3-6T, was isolated from tidal flat sediments of the Yellow Sea in the region of Tae-An. A 16S rRNA gene sequence analysis demonstrated that this isolate belongs to the Bacillus cereus group, and is closely related to Bacillus mycoides (99.0% similarity), Bacillus thuringiensis (99.0%), Bacillus weihenstephanensis (99.0%), Bacillus cereus (98.9%), Bacillus anthracis (98.8%), and Bacillus pseudomycoides (98.1%). The phylogenetic distance from any validly described Bacillus species outside the Bacillus cereus group was less than 95.6%. The DNA G+C content of the strain was 39.4 mol% and the major respiratory quinone was menaquinone-7. The major cellular fatty acids were iso-C14:0 (17.8%), iso-C16:0 (15.8%), and iso-C12:0 (11.3%). The diagnostic amino acid of the cell wall was meso-diaminopimelic acid and the major cell wall sugar was galactose. The results of DNA-DNA hybridization (<55.6%) and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain BL3-6T from the published Bacillus species. BL3-6T therefore represents a new species, for which the name Bacillus gaemokensis sp. nov. is proposed, with the type strain BL3-6T (=KCTC 13318T =JCM 15801T).  相似文献   

19.
Microbiologically influenced corrosion is a problem commonly encountered in facilities in the oil and gas industries. The present study describes bacterial enumeration and identification in diesel and naphtha pipelines located in the northwest and southwest region in India, using traditional cultivation technique and 16S rDNA gene sequencing. Phylogenetic analysis of 16S rRNA sequences of the isolates was carried out, and the samples obtained from the diesel and naphtha-transporting pipelines showed the occurrence of 11 bacterial species namely Serratia marcescens ACE2, Bacillus subtilis AR12, Bacillus cereus ACE4, Pseudomonas aeruginosa AI1, Klebsiella oxytoca ACP, Pseudomonas stutzeri AP2, Bacillus litoralis AN1, Bacillus sp., Bacillus pumilus AR2, Bacillus carboniphilus AR3, and Bacillus megaterium AR4. Sulfate-reducing bacteria were not detected in samples from both pipelines. The dominant bacterial species identified in the petroleum pipeline samples were B. cereus and S. marcescens in the diesel and naphtha pipelines, respectively. Therefore, several types of bacteria may be involved in biocorrosion arising from natural biofilms that develop in industrial facilities. In addition, localized (pitting) corrosion of the pipeline steel in the presence of the consortia was observed by scanning electron microscopy analysis. The potential role of each species in biofilm formation and steel corrosion is discussed.  相似文献   

20.
Microorganisms were isolated and identified from speleothems at Khasi hill caves, Meghalaya. The aim was to understand their biomineralization potential. Analyses of the speleothems from Krem Soitan, Krem Mawpun, and Krem Lawbah using scanning electron microscope (SEM) showed evidences for microbe–mineral interactions. SEM showed microbial reticulate and beaded filaments, cells, fiber calcites, and clusters of coccoid-like structures. A total of 113 bacterial strains were isolated and identified by a combination of conventional and molecular based tools. 105 strains that were sequenced belonged to the genus: Bacillus, Rummeliibacillus, Staphylococcus, and Brevibacterium. The BLASTn sequence search of 16S rRNA sequences with the National Centre for Biotechnology Information database to establish the identity of the strains yielded similarity scores of ≥99% with the respective organisms. The strains were identified as Bacillus simplex, Bacillus gaemokensis, Bacillus subtilis, Bacillus thuringiensis, Bacillus albus, Bacillus cereus, Bacillus anthracis, Bacillus weihenstephanensis, Rummeliibacillus stabekisii, Bacillus wiedmannii, Staphylococcus epidermidis, Rummeliibacillus pycnus, Kurthia zopfii, and Brevibacterium frigoritolerans. These strains were tested for biomineralization on B-4 medium. Five strains (B. subtilis, R. stabekisii, Staphylococcus epiderdimis, B. cereus, and B. wiedmannii) had the capability to precipitate biominerals in vitro. B. subtilis, R. stabekisii, and S. epidermidis precipitated 0.24, 0.36, and 0.35 g/L of biominerals at 22°C at the end of the four week experiment period. These strains increased the pH of the medium from 7 to 8.95. The precipitated biominerals were imaged using an ultra-high resolution field emission SEM. X-ray diffraction of the biomineral precipitated by R. stabekisii showed that it was composed of vaterite and jungite. Whereas S. epidermidis showed that it was composed of calcite, vaterite, and jungite. B. subtilis produced small, circular calcite crystals. This is the first comprehensive report on the possible evidences about the role of R. stabekisii and S. epidermidis in calcite precipitation isolated from speleothems in the Indian caves. These results allow us to postulate that the identified strains have biomineralization potential. Further evidences of the coexistence of exopolysaccharides, whisker fiber calcites, microbial filaments, and coccoid-like forms point to biogenic inputs in the cave mineral formations.  相似文献   

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