Search results for "Microbio"
showing 10 items of 8741 documents
The closure of Pak1-dependent macropinosomes requires the phosphorylation of CtBP1/BARS
2007
Membrane fission is an essential process in membrane trafficking and other cellular functions. While many fissioning and trafficking steps are mediated by the large GTPase dynamin, some fission events are dynamin independent and involve C-terminal-binding protein-1/brefeldinA-ADP ribosylated substrate (CtBP1/BARS). To gain an insight into the molecular mechanisms of CtBP1/BARS in fission, we have studied the role of this protein in macropinocytosis, a dynamin-independent endocytic pathway that can be synchronously activated by growth factors. Here, we show that upon activation of the epidermal growth factor receptor, CtBP1/BARS is (a) translocated to the macropinocytic cup and its surroundi…
The Social Life of Viruses
2021
Despite their simplicity, viruses exhibit certain types of social interactions. Situations in which a given virus achieves higher fitness in combination with other members of the viral population have been described at the level of transmission, replication, suppression of host immune responses, and host killing, enabling the evolution of viral cooperation. Although cellular coinfection with multiple viral particles is the typical playground for these interactions, cooperation between viruses infecting different cells is also established through cellular and viral-encoded communication systems. In general, the stability of cooperation is compromised by cheater genotypes, as best exemplified…
In vitro evolution of an atrazine-degrading population under cyanuric acid selection pressure: Evidence for the selective loss of a 47kb region on th…
2011
International audience; The adaptation of microorganisms to pesticide biodegradation relies on the recruitment of catabolic genes by horizontal gene transfer and homologous recombination mediated by insertion sequences (IS). This environment-friendly function is maintained in the degrading population but it has a cost which could diminish its fitness. The loss of genes in the course of evolution being a major mechanism of ecological specialization, we mimicked evolution in vitro by sub-culturing the atrazine-degrading Pseudomonas sp. ADP in a liquid medium containing cyanuric acid as the sole source of nitrogen. After 120 generations, a new population evolved, which replaced the original on…
The influence of backslopping on lactic acid bacteria diversity in tarhana fermentation
2020
Tarhana is produced at batch systems in which the microbiota has changed accordingly to the microbial load from ingredients. In order to stabilize the microbiota, the effects of backslopping carried out under different temperature regimes (25 and 30 °C), pH (3.70 and 4.00) and inoculation rates (5, 10 and 15%) on lactic acid bacteria (LAB) diversity were determined in tarhana dough. LAB and Total Aerobic Mesophilic Bacteria (TAMB) numbers increased in all tarhana dough samples subjected to backslopping. Temperature and pH significantly affected the microbiological diversity of tarhana whereas the different inoculation rates did not. Tarhana dough showed complex tarhana microbiota following …
Initiation of an Aquaculture of Sponges for the Sustainable Production of Bioactive Metabolites in Open Systems: Example, Geodia cydonium.
1999
Among Metazoa, sponges (phylum Porifera) are the richest source for different bioactive compounds. The availability of the raw material is, however, restricted. To obtain enough of the bioactive compounds for application in human therapy, sponges have to be cultured in in vitro systems. One technique for the establishment of a long-term cell culture from sponges has recently been elaborated. Here, we present a procedure to cultivate tissue samples from sponges in an open system. The species Geodia cydonium, which produces bioactive compounds, has been selected. Tissue samples of approximately 10 g were attached to the bottoms of cultivation trays. After 2 to 3 days, the tissue samples forme…
Spatial patterns of, and environmental controls on, soil properties at a riparianepaddock interface
2012
Abstract Riparian zones are prominent features of agricultural landscapes because they are the last point to intercept nutrients and sediments before they enter water bodies. We investigated the soil properties, nutrient dynamics and vegetation composition at the riparian–agriculture interface. Soil physicochemical and vegetation properties were spatially heterogeneous along the transition from the grazed paddock into the un-grazed and revegetated riparian zone. Soil C stocks varied considerably across the site, with values ranging from 2% in the paddock to 5% in the riparian zone. Using Bayesian model selection, a predictive model for total soil carbon was developed. By including soil mois…
Structural diversity and enzyme activity of volcanic soils at different stages of development and response to experimental disturbance
2008
We investigated the phospholipid fatty acid (PLFA) diversity and enzyme activities in soils from the volcano, Mt. Etna (Sicily). The soils were at sites which have been developing for different periods of time and have formed in volcanic lava of differing ages that have been supplemented with volcanic ejecta from subsequent eruptions. However, the plant communities indicated a marked successional difference between the sites and we have used this as a proxy for developmental stage. We have compared the structural and functional properties of the microbial communities in soils from the two sites and tested experimentally the hypothesis that the more diverse community was more resistant and r…
Greenhouse gas as a nutrient: methanotrophic activity in soils of hydrothermal systems
2012
Methane is the most abundant hydrocarbon in the atmosphere and a significant contributor to the radiative forcing with a global warming potential about 21 times that of CO2. Methane is released to the atmosphere by a wide number of sources, both natural and anthropogenic, with the latter being twice as large as the former. Significant amounts of geological methane, produced within the Earth’s crust (e.g. volcanic/geothermal areas), are currently released into the atmosphere (48 Tg CH4/y). Microbial oxidation in soils by methanotrophic bacteria contributes to the removal of CH4 from the atmosphere for about 3-9%. Methanotrophs belong to the Gamma- and Alpha-proteobacteria and to the recently…
Exploring methanotrophic activity in geothermal soils from Pantelleria Island (Italy)
2012
Methane is released to the atmosphere by a wide number of natural (geological and biological) and anthropogenic sources, and is the second most important greenhouse gas after CO2. Microbial oxidation in soils by methanotrophic bacteria contributes to the removal of CH4 from the atmosphere and methanotrophic activity was also detected in volcanic/geothermal areas where degassing of endogenous gases occurs. Our aim is to describe the methanotrophs at the main exhalative area of Le Favare site at Pantelleria Island, where high CH4 consumption (up to 950 ng/g/ per h) was measured. Total soil bacterial diversity was analysed by TTGE of amplified 16S rRNA genes and the diversity of proteobacteria…
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…