Search results for "BACTERIAL COMMUNIT"
showing 10 items of 70 documents
1,2-DICHLOROETHANE CONTAMINATED AQUIFER: MICROBIAL COMMUNITY RESPONSE TO BIOSTIMULATION IN MICROCOSM
2022
Preliminary results for application of culture-independent molecular methods to olive brines bacterial communities.
2006
Transformation of green table olives requires a brining stage during which olives ferment. In naturally transformed olives, both flavour improvement and debittering are associated to fermentation. Because of brine features, naturally occurring bacteria and yeasts are progressively selected by the high salt concentration, low pH and phenolic compounds with antimicrobial activity. The establishment of an adequate fermenting microflora is essential to obtain a good and safe product; then, during transformation, control of chemical and microbiological parameters is crucial. Currently, microflora is periodically monitored by plate-counting of main groups. These routine analyses, however, don’t s…
Validation and application of a PCR primer set to quantify fungal communities in the soil environment by real-time quantitative PCR
2011
Fungi constitute an important group in soil biological diversity and functioning. However, characterization and knowledge of fungal communities is hampered because few primer sets are available to quantify fungal abundance by real-time quantitative PCR (real-time Q-PCR). The aim in this study was to quantify fungal abundance in soils by incorporating, into a real-time Q-PCR using the SYBRGreen (R) method, a primer set already used to study the genetic structure of soil fungal communities. To satisfy the real-time Q-PCR requirements to enhance the accuracy and reproducibility of the detection technique, this study focused on the 18S rRNA gene conserved regions. These regions are little affec…
Microbiology meets geochemistry: geothermal flux shapes different microbial communities at the same exhalative area
2015
Volcanic/geothermal areas are sites of complex interactions between geosphere and biosphere. Pantelleria island (Southern Mediterranean Sea) hosts a high enthalpy geothermal system characterized by high CH4 and low H2S fluxes. Two sites, FAV1 and FAV2, located a few meters apart at the main exhalative area of the island (Favara Grande), recorded similar physical conditions (soil temperature 60°C, soil gas composition enriched in CH4, H2 and CO2). However, while high methanotrophic activity (59.2 nmol g-1 h-1) and high diversity of methanotrophs was detected at FAV2, FAV1 was not active and appeared deprived of methanotrophs (1). Our aim was to investigate the main factors influencing methan…
AEROBIC 1,2-DICHLOROETHANE DEGRADERS IN CONTAMINATED GROUNDWATER
2022
Erratum for Piwosz et al., "Light and Primary Production Shape Bacterial Activity and Community Composition of Aerobic Anoxygenic Phototrophic Bacter…
2020
Metabolic coupling between phytoplankton and bacteria determines the fate of dissolved organic carbon in aquatic environments, and yet how changes in the rate of primary production affect the bacterial activity and community composition remains understudied. Here, we experimentally limited the rate of primary production either by lowering light intensity or by adding a photosynthesis inhibitor. The induced decrease had a greater influence on bacterial respiration than on bacterial production and growth rate, especially at an optimal light intensity. This suggests that changes in primary production drive bacterial activity, but the effect on carbon flow may be mitigated by increased bacteria…
Effets du mode de travail du sol sur les microorganismes à l'échelle du profil cultural
2009
Soil tillage modifies the location of crop residues and soil structure and affects microbial populations and activities such as mineralization of soil organic matter. The aim of this work was to compare the effect of two tillage systems (traditional mouldboard ploughing, LT, and reduced tillage, TR) on crop residues distribution and soil structure as well as their consequences on soil microbial biomass (BM), the potential activity of C mineralization (Cmin) and soil bacterial community structure (through T-RFLP). In order to study simultaneously the effects of soil structure modifications and crop residues distribution on these microbial parameters we used a stratified sampling scheme based…
Molecular analysis of lichen-associated bacterial communities.
2006
The bacterial communities associated with 11 different lichen samples (belonging to eight different species) from different habitats were investigated. The culturable aerobic-heterotrophic fraction of the bacterial communities was isolated from nine lichen samples on protein-rich and sugar-rich/N-free media. Thirty-four bacterial isolates were purified and pooled into groups (phylotypes) by analysis of the ribosomal internal transcribed spacer polymorphism. Twenty five phylotypes were identified, each comprising between one and three isolates. One isolate of each phylotype was partially sequenced and the resulting 16S rRNA gene sequences were compared in a phylogenetic analysis. Three gener…
Grazing intensity in subarctic tundra affects the temperature adaptation of soil microbial communities
2015
Abstract Grazing by large ungulates, such as reindeer (Rangifer tarandus L.), in subarctic tundra exerts a considerable effect on the soil microclimate. Because of higher insulation by the aboveground vegetation in light versus heavily grazed areas, soil temperatures during the growing season are considerably higher under heavy grazing. Here, we hypothesized that these grazer-induced changes in soil microclimate affect the temperature sensitivity of soil microbial activity. To test this hypothesis, we conducted soil incubations at different temperatures (4 °C, 9 °C and 14 °C) for six weeks using soils from sites with contrasting long-term grazing intensities. Microbial respiration at low te…