Abundance and Antimicrobial Resistance of Three Bacterial Species along a Complete Wastewater Pathway

After consumption, antibiotic residues and exposed bacteria end up via the feces in wastewater, and therefore wastewater is believed to play an important role in the spread of antimicrobial resistance (AMR). We investigated the abundance and AMR profiles of three different species over a complete wastewater pathway during a one-year sampling campaign, as well as including antimicrobial consumption and antimicrobial concentrations analysis. A total of 2886 isolates (997 Escherichia coli, 863 Klebsiella spp., and 1026 Aeromonas spp.) were cultured from the 211 samples collected. The bacterial AMR profiles mirrored the antimicrobial consumption in the respective locations, which were highest in the hospital. However, the contribution of hospital wastewater to AMR found in the wastewater treatment plant (WWTP) was below 10% for all antimicrobials tested. We found high concentrations (7-8 logs CFU/L) of the three bacterial species in all wastewaters, and they survived the wastewater treatment (effluent concentrations were around 5 log CFU/L), showing an increase of E. coli in the receiving river after the WWTP discharge. Although the WWTP had no effect on the proportion of AMR, bacterial species and antimicrobial residues were still measured in the effluent, showing the role of wastewater contamination in the environmental surface water.</p

Determining Toxic Potencies of Water-Soluble Contaminants in Wastewater Influents and Effluent Using Gene Expression Profiling in C. elegans as a Bioanalytical Tool

With chemical analysis, it is impossible to qualify and quantify the toxic potency of especially hydrophilic bioactive contaminants. In this study, we applied the nematode C. elegans as a model organism for detecting the toxic potency of whole influent wastewater samples. Gene expression in the nematode was used as bioanalytical tool to reveal the presence, type and potency of molecular pathways induced by 24-h exposure to wastewater from a hospital (H), nursing home (N), community (C), and influent (I) and treated effluent (E) from a local wastewater treatment plant. Exposure to influent water significantly altered expression of 464 genes, while only two genes were differentially expressed in nematodes treated with effluent. This indicates a significant decrease in bioactive pollutant-load after wastewater treatment. Surface water receiving the effluent did not induce any genes in exposed nematodes. A subset of 209 genes was differentially expressed in all untreated wastewaters, including cytochromes P450 and C-type lectins related to the nematode's xenobiotic metabolism and immune response, respectively. Different subsets of genes responded to particular waste streams making them candidates to fingerprint-specific wastewater sources. This study shows that gene expression profiling in C. elegans can be used for mechanism-based identification of hydrophilic bioactive compounds and fingerprinting of specific wastewaters. More comprehensive than with chemical analysis, it can demonstrate the effective overall removal of bioactive compounds through wastewater treatment. This bioanalytical tool can also be applied in the process of identification of the bioactive compounds via a process of toxicity identification evaluation. [GRAPHICS]

Global change effects on land management in the Mediterranean region

International audienceThe Mediterranean region faces significant challenges to supply its growing population with food and living space. The region's potential to do so in the future is even more uncertain in the light of global change effects. Climate change will impact water availability in the region, which is already limited and often used at un-sustainable rates. To investigate the effects of global change and explore alternative development pathways of Mediterranean land use, we simulated two future scenarios with different land, water and biodiversity management transitions. We adopted a land systems approach, where land use and land cover are combined with data on land management, irrigation and livestock density, taking into account the characteristics of Mediterranean multifunctional landscapes, specific agricultural products, such as permanent crops, and irrigation water demands. Future land system changes were explored using the CLUMondo model for different development pathways of the region. We constrained the withdrawal of irrigation water based on existing freshwater resources. In a 'growth' scenario, we simulated a hypothetical future without consideration of environmental constraints and where food production and urban expansion are main priorities. The 'sustain-ability' scenario represents a future where limited water resources are extracted in a sustainable way and where areas of high biodiversity value are protected. The growth scenario projected significant intensification of land management, and loss of agro-silvo-pastoral mosaic systems. To achieve this, we calculate that the region would need to increase water withdrawal for irrigation significantly, resulting in increased pressure on freshwater resources. The sustainability scenario presents a way of increasing food production and at the same time improving the state of water resources, wetlands and traditional landscapes. Achieving this future would require improvements of yields of rain-fed systems and efficiencies of irrigated systems. The results indicate that coordinated environmental policy together with appropriate market access are needed to steer the regions land management towards a more sustainable future while ensuring food production

Noncoding RNA of Glutamine Synthetase I Modulates Antibiotic Production in Streptomyces coelicolor A3(2)

Overexpression of antisense chromosomal cis-encoded noncoding RNAss (ncRNAs) in glutamine synthetase I resulted in a decrease in growth, protein synthesis, and antibiotic production in Streptomyces coelicolor. In addition, we predicted 3,597 cis-encoded ncRNAs and validated 13 of them experimentally, including several ncRNAs that are differentially expressed in bacterial hormone-defective mutants.

Future land system scenarios for the Mediterranean

The Mediterranean region faces significant challenges to supply its growing population with food and living space. The region’s potential to do so in the future is even more uncertain in the light of global change effects, particularly climate and socio-economic change. Until know, it was unknown how land use and land management can respond to such global challenges. We present a set of scenarios on potential future changes to Mediterranean land systems. First, we present two different pathways in fulfilling the growing demand for crops, livestock and urban space. One is oriented towards growth, without any restrictions in terms of limiting the withdrawal of water for irrigation or expansion of protected areas. The second presents a future, where consumption of water for irrigation is reduced, and the network of protected areas is significantly expanded. The second set of scenarios presents how land use and land management might respond to different levels of reduced water losses in the irrigation systems. Irrigated cropland in the region is characterized by different levels of efficiency. In the study we show, that significant reductions of water losses is necessary in order to increase crop production in the region. The maps present the spatial distribution of Mediterranean land systems today and in the future (2050), and can be imported in a GIS. The maps are created in a Lambert Azimuthal Equal Area projection with a resolution of 2 x 2 km (custom projection with more details in the file "readme_projection"). We used the CLUMondo spatial allocation model in both studies. We present a novel approach, where we limit cropland intensification based on accessible water resources. Moreover, we studied what would decreases in water resources due to climate change mean to land use and land management. More information on the model in the publications and on www.environmentalgeography.nl The resulting scenarios can be used numerous ways: Evaluating different strategies to improve cropland productivity and increase crop production (implementing irrigation, improving irrigation efficiency, cropland intensification, crop type specialization, changes to multifunctionality…) Studying changes to Mediterranean terrestrial biodiversity and landscapes Identifying areas with different priorities: crop production, livestock grazing, biodiversity protection

Future land system scenarios for the Mediterranean

The Mediterranean region faces significant challenges to supply its growing population with food and living space. The region’s potential to do so in the future is even more uncertain in the light of global change effects, particularly climate and socio-economic change. Until know, it was unknown how land use and land management can respond to such global challenges. We present a set of scenarios on potential future changes to Mediterranean land systems. First, we present two different pathways in fulfilling the growing demand for crops, livestock and urban space. One is oriented towards growth, without any restrictions in terms of limiting the withdrawal of water for irrigation or expansion of protected areas. The second presents a future, where consumption of water for irrigation is reduced, and the network of protected areas is significantly expanded. The second set of scenarios presents how land use and land management might respond to different levels of reduced water losses in the irrigation systems. Irrigated cropland in the region is characterized by different levels of efficiency. In the study we show, that significant reductions of water losses is necessary in order to increase crop production in the region. The maps present the spatial distribution of Mediterranean land systems today and in the future (2050), and can be imported in a GIS. The maps are created in a Lambert Azimuthal Equal Area projection with a resolution of 2 x 2 km (custom projection with more details in the file "readme_projection"). We used the CLUMondo spatial allocation model in both studies. We present a novel approach, where we limit cropland intensification based on accessible water resources. Moreover, we studied what would decreases in water resources due to climate change mean to land use and land management. More information on the model in the publications and on www.environmentalgeography.nl The resulting scenarios can be used numerous ways: Evaluating different strategies to improve cropland productivity and increase crop production (implementing irrigation, improving irrigation efficiency, cropland intensification, crop type specialization, changes to multifunctionality…) Studying changes to Mediterranean terrestrial biodiversity and landscapes Identifying areas with different priorities: crop production, livestock grazing, biodiversity protection

Abundance and Antimicrobial Resistance of Three Bacterial Species along a Complete Wastewater Pathway

After consumption, antibiotic residues and exposed bacteria end up via the feces in wastewater, and therefore wastewater is believed to play an important role in the spread of antimicrobial resistance (AMR). We investigated the abundance and AMR profiles of three different species over a complete wastewater pathway during a one-year sampling campaign, as well as including antimicrobial consumption and antimicrobial concentrations analysis. A total of 2886 isolates (997 Escherichia coli, 863 Klebsiella spp., and 1026 Aeromonas spp.) were cultured from the 211 samples collected. The bacterial AMR profiles mirrored the antimicrobial consumption in the respective locations, which were highest in the hospital. However, the contribution of hospital wastewater to AMR found in the wastewater treatment plant (WWTP) was below 10% for all antimicrobials tested. We found high concentrations (7–8 logs CFU/L) of the three bacterial species in all wastewaters, and they survived the wastewater treatment (effluent concentrations were around 5 log CFU/L), showing an increase of E. coli in the receiving river after the WWTP discharge. Although the WWTP had no effect on the proportion of AMR, bacterial species and antimicrobial residues were still measured in the effluent, showing the role of wastewater contamination in the environmental surface water

Noncoding RNA of Glutamine Synthetase I Modulates Antibiotic Production in Streptomyces coelicolor A3(2)

Overexpression of antisense chromosomal cis-encoded noncoding RNAss (ncRNAs) in glutamine synthetase I resulted in a decrease in growth, protein synthesis, and antibiotic production in Streptomyces coelicolor. In addition, we predicted 3,597 cis-encoded ncRNAs and validated 13 of them experimentally, including several ncRNAs that are differentially expressed in bacterial hormone-defective mutants

Biodiversity scenarios neglect future land-use changes

International audienceEfficient management of biodiversity requires a forward-looking approach based on scenarios that explore biodiversity changes under future environmental conditions. A number of ecological models have been proposed over the last decades to develop these biodiversity scenarios. Novel modelling approaches with strong theoretical foundation now offer the possibility to integrate key ecological and evolutionary processes that shape species distribution and community structure. Although biodiversity is affected by multiple threats, most studies addressing the effects of future environmental changes on biodiversity focus on a single threat only. We examined the studies published during the last 25years that developed scenarios to predict future biodiversity changes based on climate, land-use and land-cover change projections. We found that biodiversity scenarios mostly focus on the future impacts of climate change and largely neglect changes in land use and land cover. The emphasis on climate change impacts has increased over time and has now reached a maximum. Yet, the direct destruction and degradation of habitats through land-use and land-cover changes are among the most significant and immediate threats to biodiversity. We argue that the current state of integration between ecological and land system sciences is leading to biased estimation of actual risks and therefore constrains the implementation of forward-looking policy responses to biodiversity decline. We suggest research directions at the crossroads between ecological and environmental sciences to face the challenge of developing interoperable and plausible projections of future environmental changes and to anticipate the full range of their potential impacts on biodiversity. An intergovernmental platform is needed to stimulate such collaborative research efforts and to emphasize the societal and political relevance of taking up this challenge

Global scenarios for biodiversity need to better integrate climate and land use change

International audienc