Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
1.
Arch Microbiol ; 201(9): 1285-1293, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31256199

RESUMEN

Aiming at revealing the arsenic (As) resistance of the endophytic Kocuria strains isolated from roots and stems of Sphaeralcea angustifolia grown at mine tailing, four strains belonging to different clades of Kocuria based upon the phylogeny of 16S rRNA genes were screened for minimum inhibitory concentration (MIC). Only the strain NE1RL3 was defined as an As-resistant bacterium with MICs of 14.4/0.0125 mM and 300/20.0 mM for As3+ and As5+, respectively, in LB/mineral media. This strain was identified as K. palustris based upon analyses of cellular chemical compositions (cellular fatty acids, isoprenoides, quinones, and sugars), patterns of carbon source, average nucleotide identity of genome and digital DNA-DNA relatedness. Six genes coding to enzymes or proteins for arsenate reduction and arsenite-bumping were detected in the genome, demonstrating that this strain is resistant to As possibly by reducing As5+ to As3+, and then bumping As3+ out of the cell. However, this estimation was not confirmed since no arsenate reduction was detected in a subsequent assay. This study reported for the first time the presence of phylogenetically distinct arsenate reductase genes in a Kocuria strain and evidenced the possible horizontal transfer of these genes among the endophytic bacteria.


Asunto(s)
Arseniato Reductasas/genética , Arseniatos/metabolismo , Micrococcaceae/enzimología , Micrococcaceae/genética , Arsénico/farmacología , Arsenitos/metabolismo , Pruebas de Sensibilidad Microbiana , Micrococcaceae/metabolismo , Filogenia , ARN Ribosómico 16S/genética , Tracheophyta/microbiología
2.
Microb Ecol ; 72(3): 538-48, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27324653

RESUMEN

Butane oxidation by the hydrocarbon degradation bacteria has long been described, but little is known about the microbial interaction in this process. To investigate this interaction, the efficiency of butane oxidation was estimated in monocultures and co-cultures of six strains of butane-oxidizing bacteria (BOB) and a butanol-oxidizing strain. Results showed that the butane degradation velocity was at least 26 times higher in the co-culture of the seven strains (228.50 nmol h(-1)) than in the six individual monocultures (8.71 nmol h(-1)). Gas chromatographic analysis of metabolites in the cultures revealed the accumulation of butanol in the monocultures of BOB strains but not in the co-culture with the butanol-oxidizing strain. These results evidenced a novel syntrophic association between BOB and butanol-oxidizing bacteria in the butane oxidation. The BOB strains oxidized butane into butanol, but this activity was inhibited by the accumulated butanol in monocultures, whereas the removal of butanol by the butanol-oxidizing strain in co-culture could eliminate the suppression and improve the butane degradation efficiency. In the co-culture, both BOB and butanol-oxidizing bacteria could grow and the time needed for butane complete removal was shortened from more than 192 h to less than 4 h. The unsuppressed effect of the co-culture was also consistent with the results of reverse transcription quantitative real-time PCR (RT-qPCR) of bmoX gene because increased expression of this gene was detected during the syntrophic growth compared with that in monoculture, pointing to the upregulation of bmoX in the syntrophic interaction.


Asunto(s)
Bacterias/aislamiento & purificación , Bacterias/metabolismo , Butanos/metabolismo , Consorcios Microbianos , Yacimiento de Petróleo y Gas/microbiología , Oxidación-Reducción , Bacterias/crecimiento & desarrollo , Carga Bacteriana , Proteínas Bacterianas/genética , Secuencia de Bases , Butanos/análisis , Butanoles/análisis , Butanoles/metabolismo , China , Cromatografía de Gases/métodos , Técnicas de Cocultivo , ADN Bacteriano , Genes Bacterianos/genética , Redes y Vías Metabólicas , ARN Ribosómico 16S/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Microbiología del Suelo , Factores de Tiempo
3.
Antonie Van Leeuwenhoek ; 108(1): 51-7, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25912732

RESUMEN

A Gram-negative, non-motive, aerobic and non-spore-forming strain 16-28-2(T) isolated from freshwater sediment of Taihu Lake was characterized by using a polyphasic approach. The optimum growth conditions were found to be as follows: 28 °C, pH 6.5 and 0-0.5 % NaCl in YG liquid medium. The major fatty acids were identified to be summed feature 3 (consisting of C16:1 ω7c and/or C16:1 ω6c), summed feature 8 (consisting of C18:1 ω7c and/or C18:1 ω6c), C14:0 2-OH, C17:1 ω6c, C16:0 and C18:1 ω7c 11-methyl (>5 %). Strain 16-28-2(T) was found to contain diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and sphingoglycolipid as the major polar lipids; and ubiquinone 10 (Q-10) as the major respiratory quinone. DNA G+C content of strain 16-28-2(T) was 63.5 mol % (Tm). A phylogenetic study of 16S rRNA gene indicated that strain 16-28-2(T) is a member of the genus Novosphingobium, with the highest 16S rRNA gene sequence similarity of 96.3 % with Novosphingobium lentum MT1(T) and below 96 % with the other Novosphingobium species. On the basis of the phylogenetic, phenotypic analyses and biochemical characterization, we suggest that strain 16-28-2(T) is a novel species in the genus Novosphingobium, for which the name Novosphingobium tardum sp. nov. is proposed. The type strain of N. tardum is 16-28-2(T) (=CGMCC 1.12989(T) =NBRC 110956(T)).


Asunto(s)
Sedimentos Geológicos/microbiología , Sphingomonadaceae/clasificación , Sphingomonadaceae/aislamiento & purificación , Aerobiosis , Técnicas de Tipificación Bacteriana , Composición de Base , Análisis por Conglomerados , Citosol/química , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Agua Dulce , Glucolípidos/análisis , Concentración de Iones de Hidrógeno , Lagos , Datos de Secuencia Molecular , Fosfolípidos/análisis , Filogenia , Quinonas/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Cloruro de Sodio/metabolismo , Sphingomonadaceae/genética , Sphingomonadaceae/fisiología , Temperatura
4.
World J Microbiol Biotechnol ; 31(6): 883-96, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25772498

RESUMEN

To investigate the temporal variation of the sediment prokaryote communities and their relation with the rapid increase of algae population in Taihu, a shallow eutrophic freshwater Lake, water and surface sediments were sampled from seven sites in different stages of algal bloom. The physicochemical characterization revealed positive correlations among the nutrient (N, P) parameters in the water and sediments, as well as TN/TP ratio 30.79 in average in water and 0.13 in sediments, demonstrating that P content was the limit factor for bloom in Taihu and sediment was an important nutrient resource for the water body. T-RFLP analysis of 16S rRNA genes revealed a diversity decrease of sediment prokaryotic communities along the bloom. The bacterial communities in sediments were more sensitive and shaped by the temporal changes, while archaea were more sensitive to the trophic level. The pyrosequencing data showed clear spatial and temporal changes in diversity of sediment bacteria. Betaproteobacteria was the most abundant group in all the samples, following by Delta-, Gama- and Alpha-proteobacteria, Acidobacteria, Chlorobi, Chloroflexi etc. At the genus level, Thiobacillus and Sulfuricurvum were the most dominant groups in the sediments, and the increase of Thiobacillus abundance in February might be used as bioindicator for the subsequent bloom. In addition, NO3 (-)-N was evidenced to be the main factor to regulate the bacterial community structure in the sediments. These results offered some novel and important data for the evaluation and predict the algal bloom in Taihu and can be reference for other shallow fresh water lakes.


Asunto(s)
Archaea/clasificación , Archaea/aislamiento & purificación , Bacterias/clasificación , Bacterias/aislamiento & purificación , Biodiversidad , Sedimentos Geológicos/microbiología , Lagos , Archaea/genética , Bacterias/genética , ADN de Archaea/química , ADN de Archaea/genética , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Eutrofización , Agua Dulce/química , Datos de Secuencia Molecular , Nitrógeno/análisis , Fósforo/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
5.
Int J Syst Evol Microbiol ; 62(Pt 9): 2127-2132, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22039006

RESUMEN

An orange-pigmented, Gram-reaction-positive, non-spore-forming, halophilic, alkali-tolerant rod, designated strain halo-2(T), was isolated from sediment of Xiarinaoer soda lake, in China's Inner Mongolia Autonomous Region. Strain halo-2(T) grew in a complex medium with 3-30 % (w/v) NaCl and at pH 5-10. The cell-wall peptidoglycan contained meso-diaminopimelic acid and the major respiratory isoprenoid quinone was MK-7. The predominant cellular fatty acids were anteiso-C(15 : 0) (43.6 %), anteiso-C(17 : 0) (14.8 %) and iso-C(15 : 0) (6.8 %) and the polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The genomic DNA G+C content of the novel strain was 48.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain halo-2(T) was most closely related to Bacillus agaradhaerens DSM 8721(T) (93.9 % sequence similarity). However, strain halo-2(T) could be clearly differentiated from its closest phylogenetic relatives on the basis of several phenotypic, genotypic and chemotaxonomic characteristics. Strain halo-2(T) therefore represents a novel species in a new genus for which the name Salisediminibacterium halotolerans gen. nov., sp. nov. is proposed. The type strain of the type species is halo-2(T) (= CGMCC 1.7654(T) = NBRC 104935(T)).


Asunto(s)
Bacilos Grampositivos Asporogénicos/clasificación , Lagos/microbiología , Filogenia , Microbiología del Agua , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/análisis , Sedimentos Geológicos/microbiología , Bacilos Grampositivos Asporogénicos/genética , Bacilos Grampositivos Asporogénicos/aislamiento & purificación , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
6.
Appl Microbiol Biotechnol ; 93(6): 2581-90, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22075634

RESUMEN

In this study, three bacterial communities were obtained from 12 Leonardite samples with the aim of identifying a clean, effective, and economic technique for the dissolution of Leonardite, a type of low-grade coal, in the production of humic acid (HA). The biodegradation ability and characteristics of the degraded products of the most effective bacterial community (MCSL-2), which degraded 50% of the Leonardite within 21 days, were further investigated. Analyses of elemental composition, (13)C NMR, and Fourier transform infrared revealed that the contents of C, O, and aliphatic carbon were similar in biodegraded humic acid (bHA) and chemically (alkali) extracted humic acid (cHA). However, the N and carboxyl carbon contents of bHA was higher than that of cHA. Furthermore, a positive correlation was identified between the degradation efficiency and the increasing pH of the culture medium, while increases of manganese peroxidase and esterase activities were also observed. These data demonstrated that both alkali production and enzyme reactions were involved in Leonardite solubilization by MCSL-2, although the former mechanism predominated. No fungus was observed by microscopy. Only four bacterial phylotypes were recognized, and Bacillus licheniformis-related bacteria were identified as the main group in MCSL-2 by analysis of amplified 16S rRNA genes, thus demonstrating that Leonardite degradation ability has a limited distribution in bacteria. Hormone-like bioactivities of bHA were also detected. In this study, a bacterial community capable of Leonardite degradation was identified and the products characterized. These data implicate the use of such bacteria for the exploitation of Leonardite as a biofertilizer.


Asunto(s)
Bacterias/metabolismo , Minerales/metabolismo , Álcalis/metabolismo , Bacterias/genética , Bacterias/aislamiento & purificación , Biodegradación Ambiental , Carbón Mineral/análisis , Sustancias Húmicas/análisis , Minerales/análisis , Datos de Secuencia Molecular , Filogenia , Microbiología del Suelo
7.
Microorganisms ; 9(5)2021 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-34068093

RESUMEN

Endophytic bacteria and fungi colonize plants that grow in various types of terrestrial and aquatic ecosystems. Our study investigates the communities of endophytic bacteria and fungi of halophyte Kalidium schrenkianum growing in stressed habitats with ionizing radiation. The geochemical factors and radiation (at low, medium, high level and control) both affected the structure of endophytic communities. The bacterial class Actinobacteria and the fungal class Dothideomycetes predominated the endophytic communities of K. schrenkianum. Aerial tissues of K. schrenkianum had higher fungal diversity, while roots had higher bacterial diversity. Radiation had no significant effect on the abundance of bacterial classes. Soil pH, total nitrogen, and organic matter showed significant effects on the diversity of root endophytes. Radiation affected bacterial and fungal community structure in roots but not in aerial tissues, and had a strong effect on fungal co-occurrence networks. Overall, the genetic diversity of both endophytic bacteria and fungi was higher in radioactive environments, however negative correlations were found between endophytic bacteria and fungi in the plant. The genetic diversity of both endophytic bacteria and fungi was higher in radioactive environments. Our findings suggest that radiation affects root endophytes, and that the endophytes associated with aerial tissues and roots of K. schrenkianum follow different mechanisms for community assembly and different paradigms in stress response.

8.
Front Cell Infect Microbiol ; 11: 789754, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35141169

RESUMEN

OBJECTIVE: The multicenter literature review and case studies of 3 patients were undertaken to provide an updated understanding of nocardiosis, an opportunistic bacterial infection affecting immunosuppressed nephrotic syndrome (NS) patients receiving long-term glucocorticoid and immunosuppressant treatment. The results provided clinical and microbiological data to assist physicians in managing nocardiosis patients. METHODS: Three cases between 2017 and 2018 from a single center were reported. Additionally, a systematic review of multicenter cases described in the NCBI PubMed, Web of Science, and Embase in English between January 1, 2001 and May 10, 2021 was conducted. RESULTS: This study described three cases of Nocardia infection in NS patients. The systematic literature review identified 24 cases with sufficient individual patient data. A total of 27 cases extracted from the literature review showed that most patients were > 50 years of age and 70.4% were male. Furthermore, the glucocorticoid or corticosteroid mean dose was 30.9 ± 13.7 mg per day. The average time between hormone therapy and Nocardia infection was 8.5 ± 9.7 months. Pulmonary (85.2%) and skin (44.4%) infections were the most common manifestations in NS patients, with disseminated infections in 77.8% of patients. Nodule/masses and consolidations were the major radiological manifestations. Most patients showed elevated inflammatory biomarkers levels, including white blood cell counts, neutrophils percentage, and C-reactive protein. Twenty-five patients received trimethoprim-sulfamethoxazole monotherapy (18.5%) or trimethoprim-sulfamethoxazole-based multidrug therapy (74.1%), and the remaining two patients (7.4%) received biapenem monotherapy. All patients, except the two who were lost to follow-up, survived without relapse after antibiotic therapy. CONCLUSIONS: Nephrotic syndrome patients are at high risk of Nocardia infection even if receiving low-dose glucocorticoid during the maintenance therapy. The most common manifestations of nocardiosis in NS patients include abnormal lungs revealing nodules and consolidations, skin and subcutaneous abscesses. The NS patients have a high rate of disseminated and cutaneous infections but a low mortality rate. Accurate and prompt microbiological diagnosis is critical for early treatment, besides the combination of appropriate antibiotic therapy and surgical drainage when needed for an improved prognosis.


Asunto(s)
Síndrome Nefrótico , Nocardiosis , Nocardia , Anciano , Antibacterianos/uso terapéutico , Quimioterapia Combinada , Humanos , Leprostáticos/uso terapéutico , Masculino , Estudios Multicéntricos como Asunto , Síndrome Nefrótico/complicaciones , Síndrome Nefrótico/tratamiento farmacológico , Nocardiosis/diagnóstico , Nocardiosis/tratamiento farmacológico , Nocardiosis/microbiología
9.
Zhonghua Yi Xue Za Zhi ; 89(9): 614-9, 2009 Mar 10.
Artículo en Zh | MEDLINE | ID: mdl-19595162

RESUMEN

OBJECTIVE: To investigate the effects of different mutated sites in the vpr gene of HIV on the apoptosis of host cells, and the possible mechanism thereof. METHODS: Fourteen HIV-1 vpr fragments were obtained from HIV-infected persons. Eukaryotic expression vector pcDNA3.1 (+) plasmid was extracted, the PCR purified product was double-cut by HindIII and BamH, and the cut products were ligated to vectors, thus establishing the JM109 competent cells. Sequencing was used to confirm the reconstruction of pcDNA-vpr eukaryotic expression vectors that were then transfected into HeLa cells. Blank vectors were transfected as control group. Cells were harvested after 24 hours and underwent Hoechst 33258 staining and observed under fluorescence microscope. Annexin-FITC-PI staining and flow cytometry were used to observe the percentage of apoptosis. The caspase-3 activity was detected by enzyme labeling instrument. RESULTS: The apoptotic rates shown by Hoechst and annexin--FITC-PI staining methods, and caspase-3 activity levels of the HeLa cells transfected with the gene fragments with mutated sites 70, 85, 86, and 94 cells were all lower than the cells transfected with the gene fragments without these mutated sites. The apoptosis causing ability levels of the No 1-7 recombinant plasmids (all of the Vpr AE subtype) were all lower than those of the No 8-14 plasmids (of Vpr B, AB, C, and C/BC subtypes). CONCLUSION: The apoptosis causing ability of the HIV with the vpr sequence with mutated sites 70, 85, 86, 94 is significantly lower than those without these sites. AE subtype induces lower apoptotic behavior in the hoist cells, and decreased activation of the caspase-3 pathway may be one of the mechanisms.


Asunto(s)
Apoptosis , Infecciones por VIH/virología , VIH-1/genética , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana/genética , Caspasa 3/metabolismo , Genes prv , Vectores Genéticos , Células HeLa , Humanos , Mutación , Transfección
10.
Front Microbiol ; 9: 3194, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30627123

RESUMEN

Quorum sensing (QS) plays an important role in the growth, nodulation, and nitrogen fixation of rhizobia. In this study, we show that water-soluble humic materials (WSHM) repress the expression of the QS related genes sinI, sinR, and expR in Sinorhizobium meliloti. This decreased the production of N-acetyl homoserine lactones (AHL) and exopolysaccharides (EPS), and ultimately increased S. meliloti cell density. We also identified a novel regulator, SMc03890 (renamed QsrR), which binds directly to the expR promoter. Deletion of qsrR increased expR expression. WSHM repressed the expression of expR by augmenting the interaction between QsrR and the expR promoter; this was determined by a bacterial-one-hybrid assay. These effects of WSHM on the QS system in S. meliloti may be the underlying mechanism by which WSHM increase the symbiotic nitrogen fixation of Medicago sativa inoculated with S. meliloti. This study provides the first evidence that humic acids regulate the QS of rhizobia and suggests that WSHM could be used as fertilizers to improve the efficiency of symbiotic nitrogen fixation.

11.
Bioresour Technol ; 131: 443-51, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23376835

RESUMEN

In order to investigate the details of lignin biodegradation, the characteristics and process of sugarcane bagasse (SCB) degradation by three lignin degrading fungi, Phanerochaete chrysosporium PC2, Lentinula edode LE16 and Pleurotus ostreatus PO45, were studied. We found that the ligninolytic enzymes polyphenol oxidase (PPO) and manganese peroxidase (MnP) were produced first, and that the cellulolytic enzyme CMCase was produced subsequently. These three fungi were more efficient to degrade lignin (85-93%) than hemicelluloses (64-88%) and cellulose (15-67%) in 12weeks, in which P. chrysosporium PC2 was the most efficient strain to degrade all the ingredients. Results of the FTIR and CP/MAS (13)C NMR revealed that the three fungi preferentially degraded syringyl units. The PPO and MnP as the main ligninolytic enzymes, especially the presence of PPO, were new findings in this study, which improved our knowledge of biopretreatment of SCB and evidenced these strains as valuable resource for SCB biotransformation.


Asunto(s)
Celulosa/metabolismo , Hongos/metabolismo , Residuos Industriales/prevención & control , Lignina/metabolismo , Eliminación de Residuos/métodos , Saccharum/microbiología , Agricultura/métodos , Biodegradación Ambiental , Técnicas de Cocultivo/métodos
12.
Huan Jing Ke Xue ; 33(1): 299-304, 2012 Jan.
Artículo en Zh | MEDLINE | ID: mdl-22452226

RESUMEN

Butane-oxidizing bacteria in soil sample sites from Puguang gas field in Sichuan province and Jianghan oil field in Hubei province were isolated and 16S rRNA gene sequence and phylogenetic analysis were applied. The differences of number and phylogenetic position and population diversity of hydrocarbon-oxidizing bacteria in different environment were investigated. The results show that 25 strains of butane-oxidizing bacteria were isolated. Based on sequencing of 16S rRNA gene, the species of bacteria in two samples are classified into 3 phyla including Firmicutes, Actinobacteria and Proteobacteria. The community structure of butane-oxidizing bacteria isolated from two oil samples is simple, both of them contain 4 genus including Bacillus, Pseudomonas, Rhodococcus and Arthrobacter. Strains in the genus of Ochrobactrum and Mycobacterium were only isolated from Puguang gas field. The number and population diversity of butane-oxidizing bacteria in Puguang gas field was more than those in Jianghan oil field.


Asunto(s)
Bacterias/crecimiento & desarrollo , Biodiversidad , Butanos/metabolismo , Yacimiento de Petróleo y Gas/microbiología , Microbiología del Suelo , Bacillus/crecimiento & desarrollo , Bacillus/aislamiento & purificación , Bacillus/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Biodegradación Ambiental , Oxidación-Reducción , Filogenia , Pseudomonas/crecimiento & desarrollo , Pseudomonas/aislamiento & purificación , Pseudomonas/metabolismo , ARN Ribosómico 16S/genética , Rhodococcus/crecimiento & desarrollo , Rhodococcus/aislamiento & purificación , Rhodococcus/metabolismo
13.
Huan Jing Ke Xue ; 33(8): 2735-40, 2012 Aug.
Artículo en Zh | MEDLINE | ID: mdl-23213898

RESUMEN

To improve the biomass and lipid productivity of the microalgae Chlorella pyrenoidosa-15, the carbon and nitrogen sources were screened to culture it heterotrophically. The best carbon and nitrogen sources were glucose and soy peptone, respectively. The carbon and nitrogen concentrations were optimized with the help of response surface design. The maximum biomass productivity was predicted to be 0.62 g x (L x d)(-1) with glucose and soy peptone concentrations of 17.53 g x L(-1) and 8.67 g x L(-1), respectively. The results of response surface design were validated with biomass productivity of 0.63 g x (L x d)(-1) and lipid content of 19.25%. The lipid productivity reached 121.3 mg x (L x d)(-1). In the research of Chlorella pyrenoidosa-15 cultured in non-autoclaved Beijing urban wastewater, the maximum algae biomass dry weight of 1.00 g x L(-1) was achieved with a lipid content of 24.12%. Results also showed that the treatment using Chlorella pyrenoidosa-15 effectively reduced the COD values and total nitrogen content in the wastewater, with a COD degradation rate of 80.9%, and a 69% decrease in total nitrogen content.


Asunto(s)
Biocombustibles/análisis , Chlorella/crecimiento & desarrollo , Chlorella/metabolismo , Eliminación de Residuos Líquidos/métodos , Biodegradación Ambiental , Medios de Cultivo , Técnicas de Cultivo/métodos , Gasolina/análisis , Procesos Fototróficos
14.
J Gen Appl Microbiol ; 58(5): 357-62, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23149680

RESUMEN

A Gram-negative, rod-shaped, aerobic, non-motile, bacterium (YG-17(T)) was isolated from eutrophic Taihu lake sediment. Colonies grown on YG agar plates were circular, convex, and yellow-colored. On the basis of 16S rRNA gene sequence similarity, strain YG-17(T) was shown to be closely related to Novosphingobium aromaticivorum (97.9%), followed by Novosphingobium stygium (97.5%), Novosphingobium subterranea (96.9%) and Novosphingobium taihuense (96.7%). The DNA-DNA relatedness values of strain YG-17(T) to the most phylogenetically related species N. aromaticivorum and N. stygium were 14% and 21%, respectively. The G+C content of the genomic DNA was 63.2 mol%. The major respiratory quinone was ubiquinone-10 and major fatty acids were C(18:1 ω7c), C(17:1 ω6c) and C(14:0)2-OH. Sphingoglycolipids were present, and spermidine was detected as the major polyamine. According to comparative physiological and chemotaxonomic analysis, strain YG-17(T) is proposed to be a novel species of the genus Novosphingobium, with the name of Novosphingobium sediminis sp. nov. The type strain is YG-17(T) (NBRC 106119(T)= CGMCC 1.9114(T)).


Asunto(s)
Alphaproteobacteria/clasificación , Sedimentos Geológicos/microbiología , Lagos/microbiología , Alphaproteobacteria/genética , Alphaproteobacteria/aislamiento & purificación , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/análisis , Genes Bacterianos , Filogenia , ARN Ribosómico 16S/genética , Espermidina/análisis , Esfingolípidos/análisis , Ubiquinona/análisis , Microbiología del Agua
15.
Int J Syst Evol Microbiol ; 60(Pt 6): 1339-1343, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19667365

RESUMEN

A Gram-stain-positive, rod-shaped, endospore-forming, halophilic, alkalitolerant bacterium, designated halo-1(T), was isolated from sediment of Xiarinaoer soda lake, located in the Inner Mongolia Autonomous Region of China. Strain halo-1(T) grew in the presence of 9-30 % (w/v) NaCl (optimum 19 %) and at pH 5-10 (optimum pH 9). The cell-wall peptidoglycan contained meso-diaminopimelic acid and the major respiratory isoprenoid quinone was MK-7. The predominant cellular fatty acids of the isolate were anteiso-C(15 : 0) (58.35 %), anteiso-C(17 : 0) (12.89 %) and C(16 : 0) (6.52 %). The polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, glycolipid and a phospholipid of unknown structure. The DNA G+C content of the strain was 46.4 mol%. On the basis of 16S rRNA gene sequence similarity, strain halo-1(T) showed the highest similarity (93.9 %) to Salsuginibacillus kocurii CH9d(T). Strain halo-1(T) could be clearly differentiated from its closest phylogenetic relative on the basis of several phenotypic, genotypic and chemotaxonomic features. Therefore, strain halo-1(T) represents a novel species, for which the name Salsuginibacillus halophilus sp. nov. is proposed, with the type strain halo-1(T) (=CGMCC 1.7653(T) =NBRC 104934(T)).


Asunto(s)
Bacilos Grampositivos/genética , Bacilos Grampositivos/aislamiento & purificación , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Cloruro de Sodio/metabolismo , Ambiente , Ácidos Grasos/análisis , Genotipo , Bacilos Grampositivos/clasificación , Bacilos Grampositivos/metabolismo , Datos de Secuencia Molecular , Fenotipo , Filogenia , Pigmentación , Microbiología del Agua
16.
Huan Jing Ke Xue ; 31(11): 2661-5, 2010 Nov.
Artículo en Zh | MEDLINE | ID: mdl-21250448

RESUMEN

Effects of phosphorus of low concentrations on the growth and the phosphorus removal efficiency of Scenedesmus obliquus were investigated in this study. Results showed that Scenedesmus obliquus achieved a phosphorus removal efficiency of 100% within 22 h when the initial algal cell concentration was 1 x 10(5) /mL and the initial phosphorus concentration was 0.02-0.10 mg/L. With the initial phosphorus concentration increased from 0.02 mg/L to 0.10 mg/L, both growth velocity of Scenedesmus obliquus and maximum biomass increased obviously. Research found that phosphorus concentration had a significant influence on cell morphology of algal. In the external phosphorus sufficient conditions, most of algae cell present as four cells gather round form, then transformed into two cells side by side form in the absence of external phosphorus in culture medium, Finally in single as the main form of existence.


Asunto(s)
Fósforo/aislamiento & purificación , Scenedesmus/crecimiento & desarrollo , Scenedesmus/metabolismo , Contaminantes Químicos del Agua/aislamiento & purificación , Biodegradación Ambiental , Técnicas de Cultivo , Agua Dulce/análisis , Fósforo/análisis , Fósforo/metabolismo , Scenedesmus/efectos de los fármacos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo
17.
Int J Syst Evol Microbiol ; 60(Pt 7): 1609-1612, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19700449

RESUMEN

A yellow-coloured bacterium, T41(T), was isolated from a soil sample of a subtropical rainforest in Nepal. Cells were Gram-reaction-positive, aerobic, non-motile, short rods. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain formed a cluster with Terrimonas ferruginea, Terrimonas lutea, Niabella soli, Flavisolibacter ginsengiterrae, Flavisolibacter ginsengisoli, Niastella yeongjuensis and Niastella koreensis in the phylum Bacteroidetes. The strain showed the highest sequence similarity to the type strain of Terrimonas lutea (93.2 %). The major isoprenoid quinone was MK-7 and the predominant cellular fatty acids (>10 %) were iso-15 : 0 (33.8 %), iso-15 : 1 G (13.3 %) and iso-17 : 0 3-OH (12.9 %). The DNA G+C content was 48.1 mol%. On the basis of phenotypic and phylogenetic data and genomic distinctiveness, strain T41(T) represents a novel species in a new genus in the phylum Bacteroidetes, for which the name Flavihumibacter petaseus gen. nov., sp. nov. is proposed. The type strain of Flavihumibacter petaseus is strain T41(T) (=CGMCC 1.7723(T) =NBRC 106054(T)).


Asunto(s)
Bacteroidetes/clasificación , Microbiología del Suelo , Árboles/microbiología , Bacteroidetes/genética , Bacteroidetes/aislamiento & purificación , Bacteroidetes/fisiología , Secuencia de Bases , Ácidos Grasos/análisis , Datos de Secuencia Molecular , Fenotipo , Filogenia
18.
Int J Syst Evol Microbiol ; 60(Pt 9): 2023-2026, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19819999

RESUMEN

A Gram-negative, yellow-pigmented bacterium, designated strain R2A-16(T), was isolated from sediment of Rupa Lake in Nepal and analysed using a polyphasic taxonomic approach. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain R2A-16(T) is affiliated to the genus Cloacibacterium of the family Flavobacteriaceae; 16S rRNA gene sequence similarity between strain R2A-16(T) and Cloacibacterium normanense CCUG 46293(T) was 98.07 %. The isolate contained iso-C(15 : 0) (35.6 %) as the major fatty acid and menaquinone MK-6 as the predominant respiratory quinone. The G+C content of the genomic DNA was 33.3 mol%. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain R2A-16(T) represents a novel species of the genus Cloacibacterium, for which the name Cloacibacterium rupense sp. nov. is proposed; the type strain is R2A-16(T) (=CGMCC 1.7656(T) =NBRC 104931(T)).


Asunto(s)
Flavobacteriaceae/clasificación , Flavobacteriaceae/aislamiento & purificación , Agua Dulce/microbiología , Sedimentos Geológicos/microbiología , ADN Bacteriano/genética , ADN Ribosómico/genética , Ácidos Grasos/metabolismo , Flavobacteriaceae/genética , Flavobacteriaceae/metabolismo , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética
19.
Int J Syst Evol Microbiol ; 59(Pt 11): 2666-9, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19625416

RESUMEN

A Gram-negative, rod-shaped, yellow-pigmented bacterium, designated strain R2A-7(T), was isolated from sediment of the eutrophic Taihu Lake in Jiangsu Province, China. The isolate was subjected to a taxonomic study using a polyphasic approach. Phylogenetic analysis based on the 16S rRNA gene sequences placed strain R2A-7(T) within the genus Flavobacterium in the family Flavobacteriaceae. The highest sequence similarity was found with Flavobacterium saliperosum (98.3 %), followed by other Flavobacterium species with similarities <96.0 %. The major fatty acids (>5 %) were 15 : 0 iso, 17 : 1 iso omega9c, 17 : 0 iso 3-OH, 15 : 1 iso G and 15 : 0 iso 3-OH. The G+C content of the genomic DNA of strain R2A-7(T) was 37.7 mol%. The DNA-DNA relatedness value with F. saliperosum CGMCC 1.3801(T) was 40.6 %. Molecular and phenotypic data suggest that strain R2A-7(T) represents a novel species within the genus Flavobacterium, for which the name Flavobacterium cauense is proposed. The type strain is R2A-7(T) (=CGMCC 1.7270(T)=NBRC 104929(T)).


Asunto(s)
Eutrofización , Flavobacterium/aislamiento & purificación , Agua Dulce/microbiología , Sedimentos Geológicos/microbiología , ADN Bacteriano/genética , ADN Ribosómico/genética , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Flavobacterium/clasificación , Flavobacterium/genética , Flavobacterium/metabolismo , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética
20.
Int J Syst Evol Microbiol ; 59(Pt 5): 1153-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19406810

RESUMEN

A novel strain, NJ-8(T), was isolated from sediment of the eutrophic Taihu Lake (China) and was subjected to a taxonomic study by using a polyphasic approach. The novel strain was aerobic and formed orange-pigmented colonies on R2A agar. Cells were Gram-negative single rods that were motile by means of gliding. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain NJ-8(T) belonged to the phylum Bacteroidetes, with Niastella yeongjuensis DSM 17621(T) (92.3 % gene sequence similarity) and Niastella koreensis DSM 17620(T) (92.0 % similarity) as its closest relatives. The major fatty acids (>5 % of the total) were iso-C(15 : 0) (27.8 %), iso-C(15 : 1) G (15.4 %), iso-C(17 : 0) 3-OH (14.5 %) and summed feature 3 (comprising C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH; 13.9 %). The genomic DNA G+C content was 46.6 mol%. Based on molecular and phenotypic data, strain NJ-8(T) is considered to represent a novel species of a new genus, for which the name Lacibacter cauensis gen. nov., sp. nov. is proposed. The type strain of the type species of the genus, Lacibacter cauensis, is NJ-8(T) (=CGMCC 1.7271(T)=NBRC 104930(T)).


Asunto(s)
Bacteroidetes/clasificación , Eutrofización , Agua Dulce/microbiología , Sedimentos Geológicos/microbiología , Técnicas de Tipificación Bacteriana , Bacteroidetes/genética , Bacteroidetes/aislamiento & purificación , Bacteroidetes/fisiología , Composición de Base , China , ADN Bacteriano/análisis , ADN Ribosómico/análisis , Ácidos Grasos/análisis , Genes de ARNr , Genotipo , Datos de Secuencia Molecular , Fenotipo , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Especificidad de la Especie
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA