58 research outputs found
Putative P1B-type ATPase from the bacterium Achromobacter xylosoxidans A8 alters Pb2+/Zn2+/Cd2+-resistance and accumulation in Saccharomyces cerevisiae
AbstractPbtA, a putative P1B-type ATPase from the Gram-negative soil bacterium Achromobacter xylosoxidans A8 responsible for Pb2+/Zn2+/Cd2+-resistance in Escherichia coli, was heterologously expressed in Saccharomyces cerevisiae. When present in Zn2+- and Pb2+/Cd2+-hypersensitive S. cerevisiae strains CM137 and DTY168, respectively, PbtA was able to restore Zn2+- and Pb2+-resistant phenotype. At the same time, the increase of Pb, Zn, and Cd accumulation in yeast was observed. However, Cd2+-tolerance of the pbtA-bearing yeasts dramatically decreased. The PbtA-eGFP fusion protein was localized primarily in the tonoplast and also in the plasma membrane and the perinuclear region corresponding to the endoplasmic reticulum at later growth stages. This indicates that PbtA protein is successfully incorporated into membranes in yeasts. Since PbtA caused a substantial increase of Pb2+/Zn2+-resistance and accumulation in baker's yeast, we propose its further use for the genetic modification of suitable plant species in order to obtain an effective tool for the phytoremediation of sites polluted by toxic transition metals
Phytoextraction of Heavy Metals: A Promising Tool for Clean-Up of Polluted Environment?
Pollution by heavy metals (HM) represents a serious threat for both the environment and human health. Due to their elemental character, HM cannot be chemically degraded, and their detoxification in the environment mostly resides either in stabilization in situ or in their removal from the matrix, e.g., soil. For this purpose, phytoremediation, i.e., the application of plants for the restoration of a polluted environment, has been proposed as a promising green alternative to traditional physical and chemical methods. Among the phytoremediation techniques, phytoextraction refers to the removal of HM from the matrix through their uptake by a plant. It possesses considerable advantages over traditional techniques, especially due to its cost effectiveness, potential treatment of multiple HM simultaneously, no need for the excavation of contaminated soil, good acceptance by the public, the possibility of follow-up processing of the biomass produced, etc. In this review, we focused on three basic HM phytoextraction strategies that differ in the type of plant species being employed: natural hyperaccumulators, fast-growing plant species with high-biomass production and, potentially, plants genetically engineered toward a phenotype that favors efficient HM uptake and boosted HM tolerance. Considerable knowledge on the applicability of plants for HM phytoextraction has been gathered to date from both lab-scale studies performed under controlled model conditions and field trials using real environmental conditions. Based on this knowledge, many specific applications of plants for the remediation of HM-polluted soils have been proposed. Such studies often also include suggestions for the further processing of HM-contaminated biomass, therefore providing an added economical value. Based on the examples presented here, we recommend that intensive research be performed on the selection of appropriate plant taxa for various sets of conditions, environmental risk assessment, the fate of HM-enriched biomass, economical aspects of the process, etc
Two approaches to biological decontamination of groundwater and soil polluted by aromaticsâcharacterization of microbial populations
As part of the EU project MULTIBARRIERS, six new endogenous aerobic bacterial isolates able to grow in the presence of BTmX (benzene, toluene, m-xylene) were characterized with respect to their growth specificities. Preliminary analysis included restriction fragment length polymorphism profiles and 16S rDNA sequencing. The diversity of these strains was confirmed by denaturing gradient gel electrophoresis. Additional aerobic bacterial strains were isolated from the rhizospheres of plants grown in polychlorinated biphenyl (PCB)-contaminated soils. Pot experiments were designed to show the beneficial effect of plants on the bacterial degradation of PCBs. The effect of PCB removal from soil was evaluated and bacteria isolated from three different plant species were examined for the presence of the bph operon. [Int Microbiol 2005; 8(3):205-211
Plants Rather than Mineral Fertilization Shape Microbial Community Structure and Functional Potential in Legacy Contaminated Soil
Metabolic Effects of n-3 PUFA as Phospholipids Are Superior to Triglycerides in Mice Fed a High-Fat Diet: Possible Role of Endocannabinoids
Background n-3 polyunsaturated fatty acids, namely docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), reduce the risk of cardiovascular disease and can ameliorate many of obesity-associated disorders. We hypothesised that the latter effect will be more pronounced when DHA/EPA is supplemented as phospholipids rather than as triglycerides. Methodology/Principal Findings In a âprevention studyâ, C57BL/6J mice were fed for 9 weeks on either a corn oil-based high-fat obesogenic diet (cHF; lipids ~35% wt/wt), or cHF-based diets in which corn oil was partially replaced by DHA/EPA, admixed either as phospholipids or triglycerides from marine fish. The reversal of obesity was studied in mice subjected to the preceding cHF-feeding for 4 months. DHA/EPA administered as phospholipids prevented glucose intolerance and tended to reduce obesity better than triglycerides. Lipemia and hepatosteatosis were suppressed more in response to dietary phospholipids, in correlation with better bioavailability of DHA and EPA, and a higher DHA accumulation in the liver, white adipose tissue (WAT), and muscle phospholipids. In dietary obese mice, both DHA/EPA concentrates prevented a further weight gain, reduced plasma lipid levels to a similar extent, and tended to improve glucose tolerance. Importantly, only the phospholipid form reduced plasma insulin and adipocyte hypertrophy, while being more effective in reducing hepatic steatosis and low-grade inflammation of WAT. These beneficial effects were correlated with changes of endocannabinoid metabolome in WAT, where phospholipids reduced 2-arachidonoylglycerol, and were more effective in increasing anti-inflammatory lipids such as N-docosahexaenoylethanolamine. Conclusions/Significance Compared with triglycerides, dietary DHA/EPA administered as phospholipids are superior in preserving a healthy metabolic profile under obesogenic conditions, possibly reflecting better bioavalability and improved modulation of the endocannabinoid system activity in WA
Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020
We show the distribution of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three genomic nomenclature systems to all sequence data from the World Health Organization European Region available until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation, compare the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2
Developing common protocols to measure tundra herbivory across spatial scales
Understanding and predicting large-scale ecological responses to global environmental change requires comparative studies across geographic scales with coordinated efforts and standardized methodologies. We designed, applied and assessed standardized protocols to measure tundra herbivory at three spatial scales: plot, site (habitat), and study area (landscape). The plot and site-level protocols were tested in the field during summers 2014-2015 at eleven sites, nine of them comprising warming experimental plots included in the International Tundra Experiment (ITEX). The study area protocols were assessed during 2014-2018 at 24 study areas across the Arctic. Our protocols provide comparable and easy-to-implement methods for assessing the intensity of invertebrate herbivory within ITEX plots and for characterizing vertebrate herbivore communities at larger spatial scales. We discuss methodological constraints and make recommendations for how these protocols can be used and how sampling effort can be optimized to obtain comparable estimates of herbivory, both at ITEX sites and at large landscape scales. The application of these protocols across the tundra biome will allow characterizing and comparing herbivore communities across tundra sites and at ecologically relevant spatial scales, providing an important step towards a better understanding of tundra ecosystem responses to large-scale environmental change.CGB was funded by the Estonian Research Council (grant IUT 20-28), and
the European Regional Development Fund (Centre of Excellence EcolChange). JDMS was supported by the Research
Council of Norway (262064). OG and LB were supported by the French Polar Institute (program â1036
Interactionsâ) and PRC CNRS Russie 396 (program âICCVATâ). DSH, NL, MAG, JB and JDR were supported by the
Natural Sciences and Engineering Research Council (Canada). NL, MAG, JB and JDR were supported by the Polar
Continental Shelf Program. NL was supported by the Canada Research Chair program and the Canada Foundation
for Innovation. NL and JB were supported by Environment Canada and Polar Knowledge Canada. NL and MAG were
supported by the Government of Nunavut, the Igloolik Community, and Université de Moncton. NL, MAG and JB
were supported by the Northern Scientific Training Program. JMA was funded by Carl Tryggers stiftelse för
vetenskaplig forskning and Qatar Petroleum (QUEX-CAS-QP-RD-18_19). IHM-S was funded by the UK Natural
Environmental Research Council Shrub Tundra (NE/M016323/1) grant. ISJ was funded by the University of Iceland
Research Fund. Fieldwork in Yamal peninsula (Erkuta, Sabetta and Belyi) for DE, NS and AS was supported by the
Russian Foundation for Basic Research (No: 18-05-60261 and No: 18-54-15013), Fram Centre project YaES (No:
362259), the Russian Center of Development of the Arctic, and the âYamal-LNGâ company. Fieldwork in UtqiaÄĄvik
was supported by the U.S. Fish and Wildlife Service. Fieldwork in Svalbard was supported by the Norwegian
Research Council (AFG No: 246080/E10), the Norwegian Polar Institute, Climate-ecological Observatory for Arctic
Tundra â COAT, the Svalbard Environmental protection fund (project number 15/20), and the University Centre in
Svalbard (UNIS) and the AB-338/AB-838 students of 2018. Sampling at Billefjorden was supported by GACR 17-
20839S
Fast Simulation of Weightless Neural Networks on General Purpose Parallel Computers.
Available from STL Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi
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