Consulta: subjectFacets:"Bacterial diversity"
Registros recuperados: 20
Data/hora: 02/06/2024 04:52:08

Microbial quality of soil from the Pampa biome in response to different grazing pressures
Provedor de dados: 74
Autores: Vargas,Rafael S.; Bataiolli,Renata; da Costa,Pedro B.; Lisboa,Bruno; Passaglia,Luciane Maria P.; Beneduzi,Anelise; Vargas,Luciano K.
The aim of this study was to evaluate the impact of different grazing pressures on the activity and diversity of soil bacteria. We performed a long-term experiment in Eldorado do Sul, southern Brazil, that assessed three levels of grazing pressure: high pressure (HP), with 4% herbage allowance (HA), moderate pressure (MP), with 12% HA, and low pressure (LP), with 16% HA. Two reference areas were also assessed, one of never-grazed native vegetation (NG) and another of regenerated vegetation after two years of grazing (RG). Soil samples were evaluated for microbial biomass and enzymatic (β-glucosidase, arylsulfatase and urease) activities. The structure of the bacterial community and the population of diazotrophic bacteria were evaluated by RFLP of the 16S...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterial diversity; Diazotrophic bacteria; Diversity; Grasslands; Soil microbial communities.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572015000200205

Diversity and dynamics of rare and of resident bacterial populations in coastal sands
Provedor de dados: 5
Autores: Gobet, Angelique; Boeer, Simone I.; Huse, Susan M.; Van Beusekom, Justus E. E.; Quince, Christopher; Sogin, Mitchell L.; Boetius, Antje; Ramette, Alban.
Coastal sands filter and accumulate organic and inorganic materials from the terrestrial and marine environment, and thus provide a high diversity of microbial niches. Sands of temperate climate zones represent a temporally and spatially highly dynamic marine environment characterized by strong physical mixing and seasonal variation. Yet little is known about the temporal fluctuations of resident and rare members of bacterial communities in this environment. By combining community fingerprinting via pyrosequencing of ribosomal genes with the characterization of multiple environmental parameters, we disentangled the effects of seasonality, environmental heterogeneity, sediment depth and biogeochemical gradients on the fluctuations of bacterial communities...
Tipo: Text
Palavras-chave: 454 pyrosequencing; Coastal seas; Bacterial diversity; Multivariate analysis; Rare biosphere.
Ano: 2012
URL: https://archimer.ifremer.fr/doc/00488/59947/63192.pdf

Screening and selection of growth-promoting bacteria for Dunaliella cultures
Provedor de dados: 5
Autores: Le Chevanton, Myriam; Garnier, Matthieu; Bougaran, Gael; Schreiber, Nathalie; Lukomska, Ewa; Berard, Jean-baptiste; Fouilland, E.; Bernard, Olivier; Cadoret, Jean-paul.
Previous studies have demonstrated that bacteria influence microalgal metabolism, suggesting that the selection and characterization of growth-promoting bacteria should offer a new strategy for improving industrial algal cultivation. In the present study, 48 cultivable bacteria were isolated from marine microalgae species and identified using 16S rRNA phylogenetic analysis. The recovered bacteria were found to be members of the α- and γ-Proteobacteria, Cytophaga–Flavobacterium–Bacteroides (CFB) and gram-positive monophyletic clusters. To address the effect of these bacteria on the growth of Dunaliella sp. individually, an experimental high-throughput tool was developed to simultaneously compare replicated associations. A two-step approach was used to...
Tipo: Text
Palavras-chave: Microalgae; Dunaliella; Bacteria; Interaction; Bacterial diversity.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00142/25334/24768.pdf

Abundance and diversity of Planctomycetes in a Tyrrhenian coastal system of central Italy
Provedor de dados: 5
Autores: Pizzetti, Ilaria; Gobet, Angelique; Fuchs, Bernhard M.; Amann, Rudolf; Fazi, Stefano.
The phylum Planctomycetes is involved in important processes, such as the mineralization of algal biomass and the removal of nitrogen. Using a combination of 16S rRNA sequence analysis and in situ hybridization, we analyzed the diversity and dynamics of Planctomycetes in a shallow meso-eutrophic lake, Lago di Paola, Italy. Planctomycetes detected by the probe PLA46 accounted for 1 to 5% of prokaryotic picoplankton. Abundances were higher in the coastal lake than in the adjacent marine waters. In the surface waters of the lake, the numbers of Planctomycetes fluctuated greatly, reaching a maximum of 1.5 x 10(6) cells ml(-1) in July. The hypoxic bottom waters had less variable cell abundances. The Planctomycetes counts were positively correlated with...
Tipo: Text
Palavras-chave: Coastal lake ecology; Planctomycetes; Bacterial diversity; FISH; CARD-FISH; 16S rRNA gene sequencing.
Ano: 2011
URL: https://archimer.ifremer.fr/doc/00488/59948/63196.pdf

A spatiotemporal study of bacterial community profiles associated with Atlantic bluefin tuna larvae, Thunnus thynnus L., in three Mediterranean hatcheries
Provedor de dados: 5
Autores: Gatesoupe, Joel; Coves, Denis; Ortega, Aurelio; Papandroulakis, Nikos; Vadstein, Olav; De La Gandara, Fernando.
During the first 2 years of larval rearing trials with Atlantic bluefin tuna, survival was a challenging issue. As bacterial colonization of the gut has been shown to play a key role for other species, we studied the profiles of the microbiota associated with individual larvae at different stages in three distant hatcheries. The Bacterial Community Profile (BCP) was quantified based on PCR-DGGE analyses of partial amplicons from 16S rDNA. Considerable individual variability in BCP was observed before onset of feeding, and the BCP did not show regular fluctuation during ontogenesis. Microalgae were added to the rearing tanks in two of the three hatcheries, but it was not possible to distinguish the effect of location from the effect of algal addition on...
Tipo: Text
Palavras-chave: Larval rearing; Bacterial diversity; DGGE; Thunnus thynnus.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00075/18648/16197.pdf

Bacterial diversity associated with the rhizosphere of wheat plants (Triticum aestivum): Toward a metagenomic analysis
Provedor de dados: 85
Autores: Velázquez-Sepúlveda,I; Orozco-Mosqueda,MC; Prieto-Barajas,CM; Santoyo,G.
Rhizospheric soil is one the largest reservoirs of microbial genetic diversity. Before conducting a large-scale metagenomic analysis of an environment, such as a rhizospheric soil, it is necessary to perform a pre-screening of the resident genetic diversity. In this study, we analyzed the bacterial diversity associated with the rhizosphere of wheat plants by PCR amplification, construction of a library and sequencing of 16S rDNA genes. Thirty OTUs were detected, including the Classes Alfaproteobacteria, Betaproteobacteria, Deltaproteobacteria, Gammaproteobateria, Actinobacteria, Bacilli, Clostridia and Uncultivable bacteria. Within the Gamma­proteobacteria class, the genera Pseudomonas, Stenotrophomonas and Bacillus were the most abundant, since they...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterial diversity; Rhizosphere; Wheat; 16S ribosomal genes.
Ano: 2012
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-56572012000100012

Bacteria diversity and microbial biomass in forest, pasture and fallow soils in the southwestern Amazon basin
Provedor de dados: 90
Autores: Cenciani,Karina; Lambais,Marcio Rodrigues; Cerri,Carlos Clemente; Azevedo,Lucas Carvalho Basílio de; Feigl,Brigitte Josefine.
It is well-known that Amazon tropical forest soils contain high microbial biodiversity. However, anthropogenic actions of slash and burn, mainly for pasture establishment, induce profound changes in the well-balanced biogeochemical cycles. After a few years the grass yield usually declines, the pasture is abandoned and is transformed into a secondary vegetation called "capoeira" or fallow. The aim of this study was to examine how the clearing of Amazon rainforest for pasture affects: (1) the diversity of the Bacteria domain evaluated by Polymerase Chain Reaction and Denaturing Gradient Gel Electrophoresis (PCR-DGGE), (2) microbial biomass and some soil chemical properties (pH, moisture, P, K, Ca, Mg, Al, H + Al, and BS), and (3) the influence of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Land use changes; PCR-DGGE; Bacterial diversity; Microbial biomass; Principal component analysis.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832009000400015

Microbial diversity in an Oxisol under no-tillage and conventional tillage in southern Brazil
Provedor de dados: 124
Autores: Babujia,Letícia Carlos; Silva,Adriana Pereira; Nogueira,Marco Antonio; Hungria,Mariangela.
The no-tillage (NT) system of soil management is recognized as more sustainable than conventional tillage (CT), with an important role played by soil microorganisms. The objective of this study was to estimate differences in soil microbial diversity under NT and CT at different soil depths. For that, bacterial (16S rDNA) and fungal (18S rDNA) communities were evaluated by denaturing gradient gel electrophoresis (DGGE) in a 20-year field experiment established on an Oxisol in southern Brazil on which soybean has been grown in the summer and wheat in the winter. Soil samples were collected at the depths of 0-5, 5-10, 10-20 and 20-30 cm, and submitted to DGGE analyses. The results revealed lower similarity (28%) between bacterial communities in the NT and the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterial diversity; Fungal diversity; PCR-DGGE; Soil tillage.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902014000500001

Intercropping of wheat changed cucumber rhizosphere bacterial community composition and inhibited cucumber Fusarium wilt disease
Provedor de dados: 63
Autores: Jin,Xue; Shi,Yajing; Wu,Fengzhi; Pan,Kai; Zhou,Xingang.
ABSTRACT: Enhancing the plant rhizosphere microbial community function by increasing plant diversity in the field is a promising strategy for enhancing agricultural sustainability. This study evaluated the effectiveness of the intercropping of wheat in controlling cucumber Fusarium wilt disease. Bacterial community diversity and abundance in cucumber rhizosphere were estimated by high-throughput amplicon sequencing and quantitative polymerase chain reaction (PCR). Results showed that the intercropping of wheat inhibited the severity of cucumber seedling Fusarium wilt disease, increased the alpha diversity and altered the composition of the bacterial community in cucumber rhizosphere. Compared with monocropped cucumber, intercropped cucumber had higher...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cucumis sativus L.; Triticum aestivum L.; Fusarium oxysporum f.sp. cucumerinum; Pseudomonas spp.; Bacterial diversity.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162020000500202

Ecology and biotechnological potential of bacterial community from three marine sponges of the coast of Rio de Janeiro, Brazil
Provedor de dados: 42
Autores: ARAÚJO,FÁBIO V. DE; NETTO,MARCELLE C.M.; AZEVEDO,GUSTAVO P.; JAYME,MARCELLY M.A.; NUNES-CARVALHO,MONICA C.; SILVA,MARIANA M.; CARMO,FLÁVIA L. DO.
ABSTRACT Marine sponges has been a large reservoir of microbial diversity, with the presence of many species specific populations as well as producing biologically active compounds, which has attracted great biotechnological interest. In order to verify the influence of the environment in the composition of the bacterial community present in marine sponges and biotechnological potential of bacteria isolated from these organisms, three species of sponges and the waters surrounding them were collected in different beaches of Rio de Janeiro, Brazil. The profile of the bacterial community present in sponges and water was obtained by PCR-DGGE technique and the biotechnological potential of the strains isolated by producing amylase, cellulase, protease and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterial diversity; Biosurfactants; Enzymes; Marine sponges; PCR-DGGE.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000602785

Bacterial Diversity in the Digestive Tracts of Four Indian Air-Breathing Fish Species Investigated by PCR Based Denaturing Gradient Gel Electrophoresis
Provedor de dados: 52
Autores: He,Suxu; Zhou,Zhigang; Banerjee,Goutam; Huang,Lu; Ray,Arun Kumar; Ringø,Einar.
ABSTRACT An investigation was conducted to identify the allochthonous microbiota (entire intestine) and the autochthonous microbiota in proximal intestine (PI) and distal intestine (DI) of four species of Indian air-breathing fish (climbing perch; Anabas testudineus, murrel; Channa punctatus, walking catfish; Clarias batrachus and stinging catfish; Heteropneustes fossilis) by PCR based denaturing gradient gel electrophoresis (DGGE). High similarities of the allochthonous microbiota were observed between climbing perch and murrel, walking catfish and stinging catfish, indicating similar food behavior. The autochthonous microbiota of PI and DI from climbing perch and murrel revealed more similarity, than the result obtained from walking catfish and stinging...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Allochthonous and autochthonous gut microbiota; Air-breathing fish; Bacterial diversity; DGGE.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132016000100350

Diversity of the candidate phylum Poribacteria in the marine sponge Aplysina fulva
Provedor de dados: 58
Autores: Hardoim,C.C.P.; Cox,C.J.; Peixoto,R.S.; Rosado,A.S.; Costa,R.; Elsas,J.D. van.
Poribacterial clone libraries constructed for Aplysina fulva sponge specimens were analysed with respect to diversity and phylogeny. Results imply the coexistence of several, prevalently "intraspecific" poribacterial genotypes in a single sponge host, and suggest quantitative analysis as a desirable approach in studies of the diversity and distribution of poribacterial cohorts in marine sponges.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Marine sponges; Bacterial diversity; Bacterial phylogeny; 16S rRNA gene.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822013000100048

A survey of the bacterial diversity in the cup filler of dental chair units
Provedor de dados: 58
Autores: Silva,Vítor; Figueira,Vânia; Figueiral,Helena; Manaia,Célia M.
Water from the cup filler of dental chair units (CFDC) was observed to contain sphingomonads, environmental mycobacteria and methylobacteria, among other minor bacteria. Some of the bacteria detected are recognized opportunistic pathogens. Some of these, tended to persist over time.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Dental unit water; Water safety; Bacterial diversity.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822011000300015

The effect of different growth regimes on the endophytic bacterial communities of the fern, Dicksonia sellowiana hook (Dicksoniaceae)
Provedor de dados: 58
Autores: Barros,Irene de Araújo; Araújo,Welington Luiz; Azevedo,João Lúcio.
Endophytic bacteria associated with the fern Dicksonia sellowiana were investigated. The bacterial communities from the surface-sterilized pinnae and rachis segments of the plants from the Brazilian Atlantic Rainforest that grew in native field conditions were compared with the bacterial communities from plants grown in greenhouses and plants that were initially grown in greenhouses and then transferred to the forest. From 540 pinnae and 540 rachis segments, 163 (30.2%) and 346 (64.2%) were colonized by bacteria, respectively. The main bacterial genera and species that were isolated included Bacillus spp. (B. cereus, B. megaterium, B. pumilus and B. subtilis), Paenibacillus sp., Amphibacillus sp., Gracilibacillus sp., Micrococcus sp. and Stenotrophomonas...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brazilian Tropical forest; Ferns; 16S rDNA; Bacterial diversity; Bacillus.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822010000400014

A primary assessment of the endophytic bacterial community in a xerophilous moss (Grimmia montana) using molecular method and cultivated isolates
Provedor de dados: 58
Autores: Liu,Xiao Lei; Liu,Su Lin; Liu,Min; Kong,Bi He; Liu,Lei; Li,Yan Hong.
Investigating the endophytic bacterial community in special moss species is fundamental to understanding the microbial-plant interactions and discovering the bacteria with stresses tolerance. Thus, the community structure of endophytic bacteria in the xerophilous moss Grimmia montana were estimated using a 16S rDNA library and traditional cultivation methods. In total, 212 sequences derived from the 16S rDNA library were used to assess the bacterial diversity. Sequence alignment showed that the endophytes were assigned to 54 genera in 4 phyla (Proteobacteria, Firmicutes, Actinobacteria and Cytophaga/Flexibacter/Bacteroids). Of them, the dominant phyla were Proteobacteria (45.9%) and Firmicutes (27.6%), the most abundant genera included Acinetobacter,...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Bacterial diversity; Endophytes; Moss; Molecular method; Cultivated isolates.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822014000100022

Evaluation of bacterial diversity recovered from petroleum samples using different physical matrices
Provedor de dados: 58
Autores: Dellagnezze,Bruna Martins; Vasconcellos,Suzan Pantaroto de; Melo,Itamar Soares de; Santos Neto,Eugênio Vaz dos; Oliveira,Valéria Maia de.
ABSTRACT Unraveling the microbial diversity and its complexity in petroleum reservoir environments has been a challenge throughout the years. Despite the techniques developed in order to improve methodologies involving DNA extraction from crude oil, microbial enrichments using different culture conditions can be applied as a way to increase the recovery of DNA from environments with low cellular density for further microbiological analyses. This work aimed at the evaluation of different matrices (arenite, shale and polyurethane foam) as support materials for microbial growth and biofilm formation in enrichments using a biodegraded petroleum sample as inoculum in sulfate reducing condition. Subsequent microbial diversity characterization was carried out...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterial diversity; Microbial enrichment; Petroleum reservoir; Physical support; 16S rRNA.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822016000300712

Bacterial diversity characterization in petroleum samples from Brazilian reservoirs
Provedor de dados: 58
Autores: Oliveira,Valéria Maia de; Sette,Lara Durães; Simioni,Karen Christina Marques; Santos Neto,Eugênio Vaz dos.
This study aimed at evaluating potential differences among the bacterial communities from formation water and oil samples originated from biodegraded and non-biodegraded Brazilian petroleum reservoirs by using a PCR-DGGE based approach. Environmental DNA was isolated and used in PCR reactions with bacterial primers, followed by separation of 16S rDNA fragments in the DGGE. PCR products were also cloned and sequenced, aiming at the taxonomic affiliation of the community members. The fingerprints obtained allowed the direct comparison among the bacterial communities from oil samples presenting distinct degrees of biodegradation, as well as between the communities of formation water and oil sample from the non-biodegraded reservoir. Very similar DGGE band...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterial diversity; Community DNA; Cultivation-independent analysis; Petroleum; 16S rDNA.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822008000300007

Effect of sulfonylurea tribenuron methyl herbicide on soil Actinobacteria growth and characterization of resistant strains
Provedor de dados: 58
Autores: Rachedi,Kounouz; Zermane,Ferial; Tir,Radja; Ayache,Fatima; Duran,Robert; Lauga,Béatrice; Karama,Solange; Simon,Maryse; Boulahrouf,Abderrahmane.
ABSTRACT Repeated application of pesticides disturbs microbial communities and cause dysfunctions on soil biological processes. Granstar® 75 DF is one of the most used sulfonylurea herbicides on cereal crops; it contains 75% of tribenuron-methyl. Assessing the changes on soil microbiota, particularly on the most abundant bacterial groups, will be a useful approach to determine the impact of Granstar® herbicide. For this purpose, we analyzed Actinobacteria, which are known for their diversity, abundance, and aptitude to resist to xenobiotic substances. Using a selective medium for Actinobacteria, 42 strains were isolated from both untreated and Granstar® treated soils. The number of isolates recovered from the treated agricultural soil was fewer than that...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterial diversity; Actinobacteria; Granstar® herbicide; Resistance; 16S rRNA genes.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822018000100079

Bacterial communities in mining soils and surrounding areas under regeneration process in a former ore mine
Provedor de dados: 58
Autores: Fernandes,Camila Cesário; Kishi,Luciano Takeshi; Lopes,Erica Mendes; Omori,Wellington Pine; Souza,Jackson Antonio Marcondes de; Alves,Lucia Maria Carareto; Lemos,Eliana Gertrudes de Macedo.
Abstract Human activities on the Earth's surface change the landscape of natural ecosystems. Mining practices are one of the most severe human activities, drastically altering the chemical, physical and biological properties of the soil environment. Bacterial communities in soil play an important role in the maintenance of ecological relationships. This work shows bacterial diversity, metabolic repertoire and physiological behavior in five ecosystems samples with different levels of impact. These ecosystems belong to a historical area in Iron Quadrangle, Minas Gerais, Brazil, which suffered mining activities until its total depletion without recovery since today. The results revealed Proteobacteria as the most predominant phylum followed by Acidobacteria,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Iron mine; Bacterial diversity; Functional diversity; Brazilian soils.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822018000300489

Polyphasic characterization of bacteria obtained from upland rice cultivated in Cerrado soil
Provedor de dados: 58
Autores: Braga,Lívia Fabiana; Oliveira,Fênix Araújo de; Couto,Eva Aparecida Prado do; Santos,Karina Freire d'Eça Nogueira; Ferreira,Enderson Petrônio de Brito; Martin-Didonet,Claudia Cristina Garcia.
ABSTRACT This work aimed to characterize 20 isolates obtained from upland rice plants, based on phenotypic (morphology, enzymatic activity, inorganic phosphate solubilization, carbon source use, antagonism), genotypic assays (16S rRNA sequencing) and plant growth promotion. Results showed a great morphological, metabolic and genetic variability among bacterial isolates. All isolates showed positive activity for catalase and protease enzymes and, 90% of the isolates showed positive activity for amylase, catalase and, nitrogenase. All isolates were able to metabolize sucrose and malic acid in contrast with mannitol, which was metabolized only by one isolate. For the other carbon sources, we observed a great variability in its use by the isolates. Most...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; PGPR; Associative bacteria; Bacterial diversity.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822018000100020