RESUMEN
A 98.1 Kb genomic region from B. pumilus 15.1, a strain isolated as an entomopathogen toward C. capitata, the Mediterranean fruit fly, has been characterised in search of potential virulence factors. The 98.1 Kb region shows a high number of phage-related protein-coding ORFs. Two regions with different phylogenetic origins, one with 28.7 Kb in size, highly conserved in Bacillus strains, and one with 60.2 Kb in size, scarcely found in Bacillus genomes are differentiated. The content of each region is thoroughly characterised using comparative studies. This study demonstrates that these two regions are responsible for the production, after mitomycin induction, of a phage-like particle that packages DNA from the host bacterium and a novel phage for B. pumilus, respectively. Both the phage-like particles and the novel phage are observed and characterised by TEM, and some of their structural proteins are identified by protein fingerprinting. In addition, it is found that the phage-like particle shows bacteriocin activity toward other B. pumilus strains. The effect of the phage-like particles and the phage in the toxicity of the strain toward C. capitata is also evaluated.
Asunto(s)
Bacillus pumilus , Bacteriocinas/metabolismo , Bacteriófagos , Ceratitis capitata/microbiología , Factores de Virulencia/metabolismo , Animales , Bacillus pumilus/aislamiento & purificación , Bacillus pumilus/patogenicidad , Bacillus pumilus/virología , Bacteriófagos/patogenicidad , Bacteriófagos/fisiologíaRESUMEN
In this study, Li+ biosorption profiles of Micrococcus luteus and Bacillus pumilus bacterial strains were investigated. Comparative surface characterization of the biomasses revealed that B. pumilus had a significantly greater surface negativity than the other, which had a direct positive effect on the ability to attract the Li+ ions. Biosorption experiments showed that B. pumilus cell had more efficient performance at all pH and initial Li+ concentration values in the ranges of 3.0-10.0 and 2.5-20.0 mg/L, respectively. The maximum adsorption capacities obtained at initial Li+ concentration of 20.0 mg/L and pH 9.0 were 1.160 mg Li+/g (167.1 µmol/g) and 2.280 mg Li+/g (328.5 µmol/g) for M. luteus and B. pumilus, respectively. For all the cases studied, the biosorption equilibrium was reached very quickly, suggesting that physical interaction dominated this process. Experimental data were found to be compatible with both Langmuir and Freundlich models under the studied experimental conditions. This study highlights the idea that B. pumilus bacterial strain will be a new and preferred biosorbent for Li+ ions by providing a low cost, rapid and quite efficient process.
Asunto(s)
Bacillus pumilus , Litio/metabolismo , Micrococcus luteus , Bacillus pumilus/crecimiento & desarrollo , Bacillus pumilus/aislamiento & purificación , Micrococcus luteus/crecimiento & desarrollo , Micrococcus luteus/aislamiento & purificaciónRESUMEN
Plant-rhizobacteria interaction and co-evolution developed adaptive strategies which may help the plant survive in nature. Plant rhizosphere soil isolates were analyzed to investigated the effects of rhizobacteria for promoting plant growth and suppress plant disease. Bacterial strains which isolated from plant rhizosphere soil were screened for elicitation of induced systemic resistance (ISR) on tobacco. Strain S2-3-2 results in significant reduction of disease severity on tobacco, it was identified as Bacillus pumilus by multilocus sequence analysis (MLSA). Strain S2-3-2 was deeper studied for pepper plant growth promotion and biological control activity against pepper bacterial spot disease. It was found that the pepper disease severity was decreased when the roots were drenched with strain S2-3-2, and the pepper plants had a higher weight and chlorophyll content, as compared with the mock-treated plants. Transcriptional expression of pathogenesis-related (PR) protein genes in pepper was analyzed by real-time PCR, gene expressions of CaPR1, CaPR4, and CaPR10 were increased when the plants were treated with strain S2-3-2. Moreover, strain S2-3-2 was tested for the production of indole-3-acetic acid (IAA), and it was determined to emit volatiles that enhance the growth of the tobacco plants. Interesting, heat-killed S2-3-2 enhance the pepper root growth, increase the gene expressions of CaPR4 and CaPR10 after pathogen challenge for 6 h, but limited to suppress the pepper bacterial spot disease as compare to the mock-treated plants. Strain S2-3-2 can be a potential biological control agent on the plant root for plant growth promoting and disease suppression.
Asunto(s)
Bacillus pumilus/aislamiento & purificación , Raíces de Plantas/crecimiento & desarrollo , Rizosfera , Microbiología del Suelo , Bacillus pumilus/genética , Bacillus pumilus/fisiología , Capsicum/genética , Capsicum/crecimiento & desarrollo , Capsicum/microbiología , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Tipificación de Secuencias Multilocus/métodos , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/microbiología , Nicotiana/genética , Nicotiana/crecimiento & desarrollo , Nicotiana/microbiologíaRESUMEN
Public concern for food safety and environmental issues and the increase in fungicide-resistant pathogen have enhanced the interest in developing alternative methods to fungicides to control postharvest fruit decay. In this study, a bacterial strain isolated from stale potato vermicelli was identified as Bacillus pumilus HN-10 based on morphological characteristics and 16S rRNA gene sequence analysis. Furthermore, two novel cationic antifungal peptides named P-1 and P-2 were purified from B. pumilus HN-10 using macroporous adsorbent resin AB-8, Sephadex G-100 chromatography, and reversed-phase high-performance liquid chromatography. The primary structure of P-1 and P-2, which were proved to be novel antifungal peptides by BLAST search in NCBI database, was PLSSPATLNSR and GGSGGGSSGGSIGGR with a molecular weight of 1142.28 and 1149.14 Da, respectively, as indicated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Both P-1 and P-2 exhibited strong antifungal activity against Trichothecium roseum with minimum inhibitory concentrations starting from 1 µg/mL. The two novel antifungal peptides were stable below 80 °C for 2 h, but lost their activity in 15 min at 121 °C. In addition, they were resistant to the proteolytic action of pepsin, trypsin, and papain, and stable within a wide range of pH (2.0-12.0). These results showed that P-1 and P-2 are novel cationic antifungal peptides with specific activity against T. roseum.
Asunto(s)
Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Péptidos Catiónicos Antimicrobianos/aislamiento & purificación , Péptidos Catiónicos Antimicrobianos/farmacología , Ascomicetos/efectos de los fármacos , Bacillus pumilus/metabolismo , Secuencia de Aminoácidos , Antifúngicos/química , Antifúngicos/metabolismo , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/metabolismo , Bacillus pumilus/clasificación , Bacillus pumilus/genética , Bacillus pumilus/aislamiento & purificación , ADN Bacteriano/genética , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Peso Molecular , Papaína , Pepsina A/metabolismo , Filogenia , Estabilidad Proteica , ARN Ribosómico 16S/genética , Análisis de Secuencia de Proteína , Solanum tuberosum/microbiología , Temperatura , Tripsina/metabolismoRESUMEN
The study involves isolation of arsenic resistant bacteria from soil samples. The characterization of bacteria isolates was based on 16S rRNA gene sequences. The phylogenetic consanguinity among isolates was studied employing rpoB and gltX gene sequence. RAPD-PCR technique was used to analyze genetic similarity between arsenic resistant isolates. In accordance with the results Bacillus subtilis and Bacillus pumilus strains may exhibit extensive horizontal gene transfer. Arsenic resistant potency in Bacillus sonorensis and high arsenite tolerance in Bacillus pumilus strains was identified. The RAPD-PCR primer OPO-02 amplified a 0.5kb DNA band specific to B. pumilus 3ZZZ strain and 0.75kb DNA band specific to B. subtilis 3PP. These unique DNA bands may have potential use as SCAR (Sequenced Characterized Amplified Region) molecular markers for identification of arsenic resistant B. pumilus and B. subtilis strains.
Asunto(s)
Arsénico/toxicidad , Bacillus pumilus/efectos de los fármacos , Bacillus pumilus/genética , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/genética , Reacción en Cadena de la Polimerasa/métodos , Técnica del ADN Polimorfo Amplificado Aleatorio/métodos , Bacillus pumilus/aislamiento & purificación , Bacillus subtilis/aislamiento & purificación , Evolución Molecular , Genes Bacterianos , Concentración de Iones de Hidrógeno , Funciones de Verosimilitud , Filogenia , SueloRESUMEN
This report provides the first confirmed evidence of Bacillus-like bacteria present in a wine from Washington State. These bacteria were isolated from a 2013 Pinot noir wine whose aroma was sensorially described as being 'dirty' or 'pond scum.' Based on physiological traits and genetic sequencing, three bacterial isolates were identified as Bacillus megaterium (strain NHO-1), Bacillus pumilus (strain NHO-2), and Paenibacillus polymyxa (strain NHO-3). These bacteria grew in synthetic media of low pH (pH 3.5) while some survived ethanol concentrations up to 15% v/v. However, none tolerated molecular SO2 concentrations ≥0.4 mg/l. Growth of strains NHO-1 and NHO-3 in a Merlot grape juice resulted in increases of titratable and volatile acidities while decreases in titratable acidity were noted for NHO-2.
Asunto(s)
Bacillus megaterium/aislamiento & purificación , Bacillus pumilus/aislamiento & purificación , Paenibacillus polymyxa/aislamiento & purificación , Vino/microbiología , Bacillus megaterium/genética , Bacillus megaterium/metabolismo , Bacillus pumilus/genética , Bacillus pumilus/metabolismo , Fermentación , Paenibacillus polymyxa/genética , Paenibacillus polymyxa/metabolismo , Vitis/metabolismo , Vitis/microbiología , Washingtón , Vino/análisisRESUMEN
The multifaceted role of chitinase in medicine, agriculture, environmental remediation and various other industries greatly demands the isolation of high yielding chitinase producing microorganisms with improved properties. The current study aimed to investigate the isolation, characterization and biocontrol prospective of chitinase producing bacterial strains autochthonous to the extreme conditions of mangrove ecosystems. Among the 51 bacterial isolates screened, Bacillus pumilus MCB-7 with highest chitinase production potential was identified and confirmed by 16S rDNA typing. Chitinase enzyme of MCB-7 was purified; the chitin degradation was evaluated by SEM and LC-MS. Unlike previously reported B.pumilus isolates, MCB-7 exhibited highest chitinase activity of 3.36U/mL, active even at high salt concentrations and temperature up to 60°C. The crude as well as purified enzyme showed significant antimycotic activity against agricultural pathogens such as Aspergillus flavus, Aspergillus niger, Aspergillus fumigatus, Ceratorhiza hydrophila and Fusarium oxysporum. The enzyme also exhibited biopesticidal role against larvae of Scirpophaga incertulas (Walker). [Lep.: Pyralidae], a serious agricultural pest of rice. The high chitinolytic and antimycotic potential of MCB-7 increases the prospects of the isolate as an excellent biocontrol agent. To the best of our knowledge, this is the first report of high chitinase yielding Bacillus pumilus strain from mangrove ecosystem with a biocontrol role against phytopathogenic fungi and insect larval pests.
Asunto(s)
Bacillus pumilus/metabolismo , Agentes de Control Biológico/farmacología , Quitinasas/farmacología , Fungicidas Industriales/farmacología , Mariposas Nocturnas/efectos de los fármacos , Humedales , Animales , Bacillus pumilus/aislamiento & purificación , Agentes de Control Biológico/aislamiento & purificación , Quitinasas/biosíntesis , Quitinasas/aislamiento & purificación , Transmisión de Enfermedad Infecciosa/prevención & control , Fungicidas Industriales/aislamiento & purificación , Mariposas Nocturnas/patogenicidad , ARN Ribosómico 16S/genética , Microbiología del SueloRESUMEN
Tailed phages with genomes larger than 200 kbp are classified as jumbo phage and exhibit extremely high diversity. In this study, a novel jumbo phage, vB_BpuM_BpSp, infecting pathogenic Bacillus pumilus, the cause of ginger rhizome rot disease, was isolated. Notable features of phage vB_BpuM_BpSp are the large phage capsid of 137 nm and baseplate-attached curly tail fibers. The genome of the phage is 255,569 bp in size with G+C content of 25.9 %, and it shows low similarity to known biological entities. The phage genome contains 318 predicted coding sequences. Among these predicted coding sequences, 26 genes responsible for nucleotide metabolism were found, and seven structural genes could be identified. The findings of this study provide new understanding of the genetic diversity of phages.
Asunto(s)
Fagos de Bacillus/genética , Fagos de Bacillus/aislamiento & purificación , Bacillus pumilus/virología , ADN Viral/genética , Genoma Viral , Análisis de Secuencia de ADN , Fagos de Bacillus/clasificación , Fagos de Bacillus/ultraestructura , Bacillus pumilus/aislamiento & purificación , Composición de Base , Cápside/ultraestructura , Orden Génico , Zingiber officinale/microbiología , Microscopía Electrónica de Transmisión , Sistemas de Lectura Abierta , Enfermedades de las Plantas/microbiología , Rizoma/microbiología , Homología de Secuencia de AminoácidoRESUMEN
In this paper, a plate confrontation method was used to isolate bacteria antagonistic to the rice blast fungus Magnaporthe grisea from samples collected from China's Dalian Bay. The antagonist strain LM-031 was obtained. We studied this strain's morphological, physiological and biochemical characteristics and analyzed its 16S rDNA sequence. We compared the effects of different culture conditions (type of media, carbon and nitrogen source, incubation temperature and time, and initial pH value) on the inhibitory effect against M. grisea. Strain LM-031 was preliminarily identified as Bacillus pumilus and was found to strongly inhibit M. grisea, especially when grown on BPY medium at an initial pH 7 for 72 h at 30°C. The optimum carbon and nitrogen sources for growth were lactose and peptone, respectively. The most suitable carbon and nitrogen sources for production of active substances were glucose and NH4Cl, respectively. Our results show that development and utilization of B. pumilus LM-031 has great potential for biological control of M. grisea.
Asunto(s)
Bacillus pumilus/aislamiento & purificación , Bacillus pumilus/fisiología , Magnaporthe/fisiología , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/terapia , Bacillus pumilus/genética , Bacillus pumilus/metabolismo , China , ADN Ribosómico/genética , Oryza , Agua de Mar/microbiologíaRESUMEN
Bacillus pumilus MTCC7615, a biocontrol agent isolated from rice rhizosphere was characterized to be antagonistic to Rhizoctonia solani, the pathogen causing sheath blight disease of rice. The phenazine-1-carboxylic acid gene (phc CD) of this bacterium was PCR amplified (1400 bp), cloned, and sequenced. The sequence analysis revealed the presence of two ORFs of phc CD gene commonly found in Pseudomonas species. The sequence showed 98% similarity to phc CD gene of the Pseudomonas isolate LBUM223 (DQ788993). The crude antibiotic extract from B. pumilus MTCC7615 was observed to inhibit mycelial growth of R. solani under in vitro conditions. The HPLC analysis of crude antibiotic extract from B. pumilus MTCC7615 confirmed the presence of phenazine. The study has also reported the presence of phc CD gene which is responsible for the synthesis of phenazine-1-carboxylic acid in B. pumilus. The ability of the bacterial isolate to control sheath blight disease in rice seedlings under in vivo conditions was confirmed by the pot culture experiment. The structural and functional genomics of phc C and phc D genes would lead to a better understanding of phenazine biosynthesis in B. pumilus for its efficient utilization in plant protection strategies.
Asunto(s)
Antibiosis , Bacillus pumilus/genética , Bacillus pumilus/patogenicidad , Agentes de Control Biológico , Control Biológico de Vectores , Rhizoctonia/crecimiento & desarrollo , Bacillus pumilus/aislamiento & purificación , Secuencia de Bases , ADN Bacteriano/genética , Micelio/crecimiento & desarrollo , Sistemas de Lectura Abierta/genética , Oryza/microbiología , Fenazinas/metabolismo , Enfermedades de las Plantas/microbiología , Reacción en Cadena de la Polimerasa , Rizosfera , Análisis de Secuencia de ADNRESUMEN
Wastewater-algal biomass is a promising option to biofuel production. However, microbial contaminants constitute a substantial barrier to algal biofuel yield. A series of algal strains, Nannochloris oculata and Chlorella vulgaris samples (n = 30), were purchased from the University of Texas, and were used for both stock flask cultures and flat-panel vertical bioreactors. A number of media were used for isolation and differentiation of potential contaminants according to laboratory standards (CLSI). Conventional PCR amplification was performed followed by 16S rDNA sequencing to identify isolates at the species level. Nanotherapeutics involving a nanomicellar combination of natural chitosan and zinc oxide (CZNPs) were tested against the microbial lytic groups through Minimum Inhibitory Concentration (MIC) tests and Transmission Electronic Microscopy (TEM). Results indicated the presence of Pseudomonas spp., Bacillus pumilus/ safensis, Cellulosimicrobium cellulans, Micrococcus luteus and Staphylococcus epidermidis strains at a substantial level in the wastewater-fed algal reactors. TEM confirmed the effectiveness of CZNPs on the lytic group while the average MICs (mg/mL) detected for the strains, Pseudomonas spp, Micrococcus luteus, and Bacillus pumilus were 0.417, 3.33, and 1.458, respectively. Conclusively, CZNP antimicrobials proved to be effective as inhibitory agents against currently identified lytic microbial group, did not impact algae cells, and shows promise for in situ interventions.
Asunto(s)
Biotecnología/instrumentación , Quitosano/farmacología , Aguas Residuales/microbiología , Óxido de Zinc/farmacología , Bacillus pumilus/efectos de los fármacos , Bacillus pumilus/aislamiento & purificación , Biocombustibles , Biomasa , Reactores Biológicos/microbiología , Biotecnología/métodos , Chlorella vulgaris , Chlorophyta , Pruebas de Sensibilidad Microbiana , Micrococcus luteus/efectos de los fármacos , Micrococcus luteus/aislamiento & purificación , Nanotecnología/instrumentación , Nanotecnología/métodos , Pseudomonas/efectos de los fármacos , Pseudomonas/aislamiento & purificación , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/aislamiento & purificaciónRESUMEN
Bioremediation of surfactants in water bodies holds significant ecological importance as they are contaminants of emerging concern posing substantial threats to the aquatic environment. Microbes exhibiting special ability in terms of bioremediation of contaminants have always been reported to thrive in extraordinary environmental conditions that can be extreme in terms of temperature, lack of nutrients, and salinity. Therefore, in the present investigation, a total of 46 bacterial isolates were isolated from the Indian sector of the Southern Ocean and screened for degradation of sodium dodecyl sulphate (SDS). Further, two Gram-positive psychrotolerant bacterial strains, ASOI-01 and ASOI-02 were identified with significant SDS degradation potential. These isolates were further studied for growth optimization under different environmental conditions. The strains were characterized as Staphylococcus saprophyticus and Bacillus pumilus based on morphological, biochemical, and molecular (16S RNA gene) characteristics. The study reports 88.9% and 93.4% degradation of SDS at a concentration of 100 mgL-1, at 20 °C, and pH 7 by S. saprophyticus ASOI-01 and B. pumilus ASOI-02, respectively. The experiments were also conducted in wastewater samples where a slight reduction in degradation efficiency was observed with strains ASOI-01 and ASOI-02 exhibiting 76.83 and 64.93% degradation of SDS respectively. This study infers that these bacteria can be used for the bioremediation of anionic surfactants from water bodies and establishes the potential of extremophilic microbes for the utilization of sustainable wastewater management.
Asunto(s)
Bacillus pumilus , Biodegradación Ambiental , Agua de Mar , Dodecil Sulfato de Sodio , Staphylococcus saprophyticus , Dodecil Sulfato de Sodio/metabolismo , Bacillus pumilus/genética , Bacillus pumilus/metabolismo , Bacillus pumilus/aislamiento & purificación , Bacillus pumilus/clasificación , Staphylococcus saprophyticus/genética , Staphylococcus saprophyticus/aislamiento & purificación , Staphylococcus saprophyticus/metabolismo , Staphylococcus saprophyticus/clasificación , Agua de Mar/microbiología , Tensoactivos/metabolismo , Filogenia , ARN Ribosómico 16S/genética , Contaminantes Químicos del Agua/metabolismo , Aguas Residuales/microbiologíaRESUMEN
Rice (Oryza sativa L.) growth and productivity has been negatively affected due to high soil salinity. However, some salt-tolerant plant growth-promoting bacteria (ST-PGPB) enhance crop growth and reduce the negative impacts of salt stress through regulation of some biochemical, physiological, and molecular features. Total thirty six ST-PGPB were isolated from sodic soil of eastern Uttar Pradesh, India, and screened for salt tolerance at different salt (NaCl) concentrations up to 2000 millimolar (mM). Out of thirty-six, thirteen strains indicated better growth and plant growth properties (PGPs) in NaCl amended medium. Among thirteen, one most effective Bacillus pumilus strain JPVS11 was molecularly characterized, which showed potential PGPs, such as indole-3-acetic acid (IAA),1-aminocyclo propane-1-carboxylicacid (ACC) deaminase activity, P-solubilization, proline accumulation and exopolysaccharides (EPS) production at different concentrations of NaCl (0 -1200 mM). Pot experiment was conducted on rice (Variety CSR46) at different NaCl concentrations (0, 50, 100, 200, and 300 mM) with and without inoculation of Bacillus pumilus strain JPVS11. At elevated concentrations of NaCl, the adverse effects on chlorophyll content, carotenoids, antioxidant activity was recorded in non-inoculated (only NaCl) plants. However, inoculation of Bacillus pumilus strain JPVS11 showed positive adaption and improve growth performance of rice as compared to non-inoculated in similar conditions. A significant (P < 0.05) enhancement plant height (12.90-26.48%), root length (9.55-23.09%), chlorophyll content (10.13-27.24%), carotenoids (8.38-25.44%), plant fresh weight (12.33-25.59%), and dry weight (8.66-30.89%) were recorded from 50 to 300 mM NaCl concentration in inoculated plants as compared to non-inoculated. Moreover, the plants inoculated with Bacillus pumilus strain JPVS11showed improvement in antioxidant enzyme activities of catalase (15.14-32.91%) and superoxide dismutase (8.68-26.61%). Besides, the significant improvement in soil enzyme activities, such as alkaline phosphatase (18.37-53.51%), acid phosphatase (28.42-45.99%), urease (14.77-47.84%), and ß-glucosidase (25.21-56.12%) were recorded in inoculated pots as compared to non-inoculated. These results suggest that Bacillus pumilus strain JPVS11 is a potential ST-PGPB for promoting plant growth attributes, soil enzyme activities, microbial counts, and mitigating the deleterious effects of salinity in rice.
Asunto(s)
Bacillus pumilus/fisiología , Oryza/crecimiento & desarrollo , Oryza/microbiología , Desarrollo de la Planta , Estrés Salino/fisiología , Plantas Tolerantes a la Sal/crecimiento & desarrollo , Plantas Tolerantes a la Sal/microbiología , Suelo/química , Antioxidantes , Bacillus pumilus/clasificación , Bacillus pumilus/genética , Bacillus pumilus/aislamiento & purificación , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Clorofila , Cianuro de Hidrógeno/metabolismo , Ácidos Indolacéticos , Fijación del Nitrógeno , Fosfatos/metabolismo , Prolina/metabolismo , Salinidad , Tolerancia a la Sal/fisiología , Semillas/microbiología , Sideróforos/metabolismo , Microbiología del Suelo , Estrés FisiológicoRESUMEN
The capacity of four bacterial strains isolated from productive soil potato fields to solubilize tricalcium phosphate on Pikovskaya agar or in a liquid medium was evaluated. A bacterial strain was selected to evaluate in vitro capacity of plant-growth promotion on Solanum tuberosum L. culture. Bacterial strain A3 showed the highest value of phosphate solubilization, reaching a 20 mm-diameter halo and a concentration of 350 mg/l on agar and in a liquid medium, respectively. Bacterial strain A3 was identified by 16S rDNA analysis as Bacillus pumilus with 98% identity; therefore, it is the first report for Bacillus pumilus as phosphate solubilizer. Plant-growth promotion assayed by in vitro culture of potato microplants showed that the addition of bacterial strain A3 increased root and stems length after 28 days. It significantly increased stem length by 79.3%, and duplicated the fresh weight of control microplants. In this paper, results reported regarding phosphorus solubilization and growth promotion under in vitro conditions represent a step forward in the use of innocuous bacterial strain biofertilizer on potato field cultures.
Asunto(s)
Bacterias/metabolismo , Fosfatos/metabolismo , Microbiología del Suelo , Solanum tuberosum/crecimiento & desarrollo , Bacillus pumilus/clasificación , Bacillus pumilus/genética , Bacillus pumilus/aislamiento & purificación , Bacillus pumilus/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Cinética , Filogenia , Raíces de Plantas/crecimiento & desarrollo , Tallos de la Planta/crecimiento & desarrollo , ARN Ribosómico 16S/genética , Rizosfera , Solanum tuberosum/metabolismo , Sacarosa/metabolismoRESUMEN
Aflatoxin M1 (AFM1 ) is a potent mycotoxin which causes serious health concerns in developing countries, where it is mainly found in milk, meat, and other foods. Biological detoxification is a promising method for eliminating AFM1 . The aim of this work was to search for AFM1 -degrading bacterial strains from animal waste, soil, and activated sludge. High-performance liquid chromatography and Fourier-transform infrared spectroscopy were used to analyze the AFM1 degradation products. A strain designated E-1-1-1 was obtained from African elephants feces, with the degradation ratio of AFM1 reaching 89.55% in 12 hr. Based on morphology, physiological and biochemical tests, and 16S rRNA gene sequence analysis, strain E-1-1-1 was identified as Bacillus pumilus. The culture supernatant of B. pumilus E-1-1-1 degraded AFM1 effectively, whereas the cells and cell extracts of B. pumilus E-1-1-1 were far less effective. Carbon and nitrogen sources had highly significant effects on the degradation of AFM1 by B. pumilus E-1-1-1. The AFM1 -degrading strain, B. pumilus E1-1-1, could have great potential in industrial applications.
Asunto(s)
Aflatoxina M1/metabolismo , Bacillus pumilus/metabolismo , Venenos/metabolismo , Animales , Bacillus pumilus/clasificación , Bacillus pumilus/aislamiento & purificación , Biotransformación , Cromatografía Líquida de Alta Presión , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Elefantes , Heces/microbiología , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Aguas del Alcantarillado/microbiología , Microbiología del Suelo , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Here we show that Bacillus pumilus ICVB403 recently isolated from copepod eggs is able to produce, after 48-72 h of growth in Landy medium, extracellular inhibitory compounds, which are active against Staphylococcus aureus ATCC 25923, methicillin-resistant S. aureus (MRSA) ATCC 43300, MRSA-S1, Staphylococcus epidermidis 11EMB, Staphylococcus warneri 27EMB, and Staphylococcus hominis 13EMB. Moreover, these extracellular inhibitory compound(s) were able to potentiate erythromycin against the aforementioned staphylococci. The minimum inhibitory concentration (MIC) of erythromycin was reduced from 32 µg/mL to 8 µg/mL for MRSA ATCC 43300 and MRSA SA-1 strains, and from 32-64 µg/mL to 4 µg/mL for S. epidermidis 11EMB and S. hominis 13EMB strains.The genome sequencing and analysis of B. pumilus ICVB403 unveiled 3.666.195 nucleotides contained in 22 contigs with a G + C ratio of 42.0%, 3.826 coding sequences, and 73 RNAs. In silico analysis guided identification of two putative genes coding for synthesis of surfactin A, a lipopeptide with 7 amino acids, and for a circular bacteriocin belonging to the circularin A/uberolysin family, respectively.
Asunto(s)
Antibacterianos/farmacología , Bacillus pumilus/química , Bacillus pumilus/genética , Bacillus pumilus/aislamiento & purificación , Bacteriocinas/farmacología , Copépodos/microbiología , Huevos/microbiología , Lipopéptidos/farmacología , Animales , Antibacterianos/metabolismo , Bacillus pumilus/metabolismo , Bacteriocinas/genética , Bacteriocinas/metabolismo , Genoma Bacteriano , Lipopéptidos/genética , Lipopéptidos/metabolismo , Pruebas de Sensibilidad Microbiana , Análisis de Secuencia de ADN , Staphylococcus aureus/clasificación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrolloRESUMEN
To increase the shelf life of edible insects, modern techniques (e.g. freeze-drying) add to the traditional methods (degutting, boiling, sun-drying or roasting). However, microorganisms become inactivated rather than being killed, and when rehydrated, many return to vegetative stadia. Crickets (Gryllus bimaculatus) and superworms (Zophobas atratus) were submitted to four different drying techniques (T1 = 10' cooking, 24 h drying at 60â; T2 = 10' cooking, 24 h drying at 80â; T3 = 30' cooking, 12 h drying at 80â, and 12 h drying at 100â; T4 = boiling T3-treated insects after five days) and analysed for total bacteria counts, Enterobacteriaceae, staphylococci, bacilli, yeasts and moulds counts, E. coli, salmonellae, and Listeria monocytogenes (the latter three being negative throughout). The microbial counts varied strongly displaying species- and treatment-specific patterns. T3 was the most effective of the drying treatments tested to decrease all counts but bacilli, for which T2 was more efficient. Still, total bacteria counts remained high (G. bimaculatus > Z. atratus). Other opportunistically pathogenic microorganisms (Bacillus thuringiensis, B. licheniformis, B. pumilis, Pseudomonas aeruginosa, and Cryptococcus neoformans) were also encountered. The tyndallisation-like T4 reduced all counts to below detection limit, but nutrients leakage should be considered regarding food quality. In conclusion, species-specific drying procedures should be devised to ensure food safety.
Asunto(s)
Contaminación de Alimentos/prevención & control , Manipulación de Alimentos , Microbiología de Alimentos , Gryllidae/microbiología , Calor , Hiperfagia/microbiología , Animales , Bacillus licheniformis/aislamiento & purificación , Bacillus pumilus/aislamiento & purificación , Bacillus thuringiensis/aislamiento & purificación , Recuento de Colonia Microbiana , Seguridad de Productos para el Consumidor , Cryptococcus neoformans/aislamiento & purificación , Desecación , Escherichia coli/aislamiento & purificación , Inocuidad de los Alimentos , Límite de Detección , Listeria monocytogenes/aislamiento & purificación , Pseudomonas aeruginosa/aislamiento & purificación , Salmonella/aislamiento & purificaciónRESUMEN
Chitinase and surfactin-mediated biocontrol of Rhizoctonia solani and Fusarium oxysporum causing wilt and root rot of Fagopyrum esculentum respectively has been studied in this communication. Bacillus pumilus MSUA3 as a potential bacterial strain strongly inhibited the growth of R. solani and F. oxysporum involving the chitinolytic enzymes and an antibiotic surfactin. Plant growth promoting attributes seem to be involved in plant growth promotion and yield attributes. The action of cell-free culture supernatant (CFCS) was found deleterious to F. oxysporum and R. solani even in the heat-treated (boiled/autoclaved) CFCS. The possible involvement of surfactin in disease control was revealed by colony PCR amplification of SrfA. Chitinolytic enzyme and antibiotic surfactin evidenced differential biocontrol of F. oxysporum and R. solani by B. pumilus MSUA3. A significant reduction in disease index under gnotobiotic conditions and productivity enhancement of F. esculentum using vermiculite-based bioformulation revealed B. pumilus MSUA3 as a successful potential biocontrol agent (BCA) and an efficient plant growth promoting rhizobacterium (PGPR) for disease management and productivity enhancement of buckwheat crop.
Asunto(s)
Antibiosis , Bacillus pumilus/fisiología , Agentes de Control Biológico , Fagopyrum/microbiología , Fusarium/fisiología , Micosis , Rhizoctonia/fisiología , Antifúngicos/metabolismo , Bacillus pumilus/clasificación , Bacillus pumilus/genética , Bacillus pumilus/aislamiento & purificación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Quitinasas/metabolismo , Fagopyrum/crecimiento & desarrollo , Fusarium/crecimiento & desarrollo , Fusarium/patogenicidad , Péptido Sintasas/genética , Péptido Sintasas/metabolismo , Filogenia , Desarrollo de la Planta , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Raíces de Plantas/microbiología , Rhizoctonia/crecimiento & desarrollo , Rhizoctonia/patogenicidad , Microbiología del Suelo , Tensoactivos/metabolismo , Tensoactivos/farmacologíaRESUMEN
Decabromodiphenyl ether (BDE-209) is a brominated flame retardant and a priority contaminant. Currently, little information is available about its significance in the environment, specifically about its susceptibility to aerobic biotransformation at low temperature. In this work, five phylogenetically diverse BDE-209-degrading bacterial strains were isolated from river sediments of northern China. These strains were distributed among four different genera-Acinetobacter, Pseudomonas, Bacillus and Staphylococcus. All five isolates were capable of growing on BDE-209, among which two isolates show better growth. By detailed morphological, physiological, and biochemical characteristics and 16S rDNA sequence analysis, the two strains were identified and named as Staphylococcus haemolyticus LY1 and Bacillus pumilus LY2. The two bacteria can grow in mineral salt medium containing BDE-209 substrate across the temperatures ranging from 2.5 to 35 °C, with an optimum temperature of 25 °C which could be considered as psychrotrophs accordingly. The degradation experiment showed that more than 70.6 and 85.5 % of 0.5 mg/L BDE-209 were degraded and the highest mineralization efficiencies of 29.8 and 39.2 % were achieved for 0.5 mg/L BDE-209 by S. haemolyticus LY1 and B. pumilus LY2, respectively. To the best of our knowledge, this is the first demonstration for the biodegradation of BDE-209 by two psychrotrophic bacteria isolated from environment.