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Worldwide, obesity leads to major diseases in adults. Infants are affected as well, particularly because of growth and development issues. In this article we describe cases of early dental eruption in overweight and obese children, almost 1 year earlier than expected. The relations and mechanisms that cause these alterations remain to be determined.

To assess effects of N loads, season, and down-estuary transit on estuarine concentrations of nitrate (NO3), ammonium (NH4), dissolved organic nitrogen (DON), and total dissolved nitrogen (TDN), we sampled three estuaries within Waquoit Bay, MA (USA), subject to different N loads, from spring to fall, at nine stations spanning the salinity range. Conventional statistical analysis on the basis of entire data for the three estuaries suggested significant effects of N loads on concentrations, but comparisons with effect size measures suggested that the effects were minor, largely an artifactual result from the large number of samples. Constraining variation by binning data into weekly means, and partitioning data by season (summer vs. spring-fall) and down-estuary transit (based on salinity) improved interpretations, allowing emergence of detectable increases in NO3 concentrations in estuaries subject to larger N loads, confirmed interactions between N load and season (seasonal increases in NO3 larger in estuaries subject to higher N loads), and down-estuary gradients (highest NO3 concentrations in fresher reaches and significant down-estuary decreases in NO3). NH4 and DON were less responsive to N loads, with rapid uptake of NH4 and seasonal trajectories of DON subject to within-estuary features. TDN concentrations decreased down-estuary, with 13–36% of loss attributable to within-estuary interception, a considerable effect in spite of short water residence times. Management implications include the need to sample seasonally and cover the salinity gradient, checking conventional statistical analyses of pooled data from large databases, using effect size measures to ensure meaningful biological and management results, and attention to the limited lability of DON often included in considering estuarine TDN and N loads.

Microplastic particles are widespread in marine sediments and the abundance of the different types of particles vary widely. In this paper we demonstrate that salt marshes effectively capture microplastics in their sediments, and that microplastic accumulations increase with the level of urbanization of the land surrounding estuarine areas. We extracted microplastics from sediment cores in salt marshes of SE New England estuaries at different degrees of urbanization and land use intensity. Microplastics were present everywhere, but their abundances increased markedly with the degree of urbanization of the land. Microplastic fragment counts were linked to nearby urbanization and their abundances seemed to be linked to more local, within-watershed inputs. The number of fibers was similar across all sites suggesting that fiber accumulation in these sediments is likely influenced by effective long-distance transport from large-scale areas. The sedimentary record confirmed that microplastics have been accumulating in these estuaries since the early 1950s, and their abundances have increased greatly in more recent years in response to the progressive urbanization of the watersheds and intensification of land uses. Our results highlight the role of salt marsh sediments as sinks for microplastics in the marine environment.

El labio y paladar hendido es una de las patologías congénitas con mayor prevalencia en el mundo. En el presente trabajo se hace un análisis de 12 PNU localizados en las secuencias genómicas de ABCA4, BMP4, MSX1, SUMO1, VAX1 y IRF6, bajo una perspectiva epidemiológica, de genética molecular, genómica y de genética de poblaciones; todo lo anterior aplicado a una población de Querétaro, México, de origen genético mixto. Material y métodos: Se realizó un estudio observacional, analítico y descriptivo a partir de muestras de 93 tríadas (sujetos de estudio y sus padres). Al seleccionar PNU que puedan ser diferenciados por medio de RFLP esperamos distinguir entre marcadores genéticos que: 1) cumplan con la ecuación de equilibrio de Hardy-Weinberg y 2) validarlos como potenciales marcadores genéticos para ser empleados en estudios de asociación en poblaciones cerradas de origen genético mixto con labio y paladar hendido (Amealco, Querétaro, México). De ser así, posteriormente se plantea probar las frecuencias obtenidas con una población seleccionada genéticamente cerrada de Amealco, Querétaro. Resultados: Después de realizar el análisis RFLP de 12 PNU localizados en la secuencia de genes ABCA4, BMP4, MSX1, SUMO1, VAX1 y IRF6, hallamos el mismo alelo para PNU analizado, el cual se encuentra en el 100% de la población. Conclusión: De los 12 PNU analizados, en este reporte, por primera vez se menciona la frecuencia de cinco de ellos. Los restantes siete presentaron la misma frecuencia reportada en la literatura. Aunque los PNU seleccionados no fueron de utilidad como marcadores genéticos debido a que el mismo alelo está presente en el 100% de la población general. El hecho de haberlos encontrado en el mismo genotipo de todas las muestras indica que la población de la ciudad de Querétaro es genéticamente cerrada y con base en esto extremadamente útil para futuras validaciones de otros PNU como posibles marcadores genéticos.

Sinorhizobium meliloti synthesizes a linear mixed-linkage (1 → 3)(1 → 4)-β-d-glucan (ML β-glucan, MLG) in response to high levels of cyclic diguanylate (c-di-GMP). Two proteins BgsA and BgsB are required for MLG synthesis, BgsA being the glucan synthase which is activated upon c-di-GMP binding to its C-terminal domain. Here we report that the product of bgrR (SMb20447) is a diguanylate cyclase (DGC) that provides c-di-GMP for the synthesis of MLG by BgsA. bgrR is the first gene of a hexacistronic bgrRSTUWV operon, likely encoding a partner-switching regulatory network where BgrR is the final target. Using different approaches, we have determined that the products of genes bgrU (containing a putative PP2C serine phosphatase domain) and bgrW (with predicted kinase effector domain), modulate the phosphorylation status and the activity of the STAS domain protein BgrV. We propose that unphosphorylated BgrV inhibits BgrR DGC activity, perhaps through direct protein–protein interactions as established for other partner switchers. A bgrRSTUWV operon coexists with MLG structural bgsBA genes in many rhizobial genomes but is also present in some MLG non-producers, suggesting a role of this partner-switching system in other processes besides MLG biosynthesis., This work was supported by Grants BIO2014-55075-P, BIO2017-83533-P and BIO2015-64480/R MINECO/FEDEREU. I.B. was supported by a Ministerio de Educación FPU fellowship (AP2010-0811). DPM was supported by Andalucía Talent Hub Program launched by the Andalusian Knowledge Agency, co-funded by the European Union’s Seventh Framework Program, Marie Skłodowska-Curie actions (COFUND –Grant Agreement no. 291780) and the Ministry of Economy Innovation, Science and Employment of the Junta de Andalucía

Concern over the ecological damage of excess nitrogen has brought increased attention to the role of research institutions and universities in contributing to this problem. Institutions often utilize the concept of the ecological ‘footprint’ to quantify and track nitrogen emissions resulting from their activities and guide plans and commitments to reduce emissions. Often, large-scale changes and commitments to reduce nitrogen footprints are not feasible at small institutions due to monetary and manpower constraints. We partnered with managers in the dining and facilities departments at the Marine Biological Laboratory (MBL), a small research institution in Woods Hole, Massachusetts, to develop five low-effort strategies to address nitrogen emissions at the institution using only resources currently available within those departments. Each proposed strategy achieved emissions reductions in their sector and in the overall nitrogen footprint of the MBL. If all modelled strategies are applied simultaneously, the MBL can achieve a 7.7% decrease in its nitrogen footprint. Managers at MBL considered strategies that required no monetary input most feasible. The intersection of carbon and nitrogen emissions also means the modelled strategies had the co-benefit of reducing the MBL’s carbon footprint, strengthening the argument for applying these strategies. This paper may serve as a model for similar institutions looking to reduce the ecological impact of their activities.

This article shares the experiences, observations, and discussions that occurred during the completing of an ecosystem services (ES) indicator framework to be used at European Union (EU) and Member States' level. The experience base was drawn from 3 European research projects and 14 associated case study sites that include 13 transitional-water bodies (specifically 8 coastal lagoons, 4 riverine estuaries, and 1 fjord) and 1 coastal-water ecosystem. The ES pertinent to each case study site were identified along with indicators of these ES and data sources that could be used for mapping. During the process, several questions and uncertainties arose, followed by discussion, leading to these main lessons learned: 1) ES identification: Some ES that do not seem important at the European scale emerge as relevant at regional or local scales; 2) ES indicators: When direct indicators are not available, proxies for indicators (indirect indicators) might be used, including combined data on monitoring requirements imposed by EU legislation and international agreements; 3) ES mapping: Boundaries and appropriate data spatial resolution must be established because ES can be mapped at different temporal and spatial scales. We also acknowledge that mapping and assessment of ES supports the dialogue between human well-being and ecological status. From an evidence-based marine planning-process point of view, mapping and assessment of marine ES are of paramount importance to sustainable use of marine natural capital and to halt the loss of marine biodiversity. Integr Environ Assess Manag 2016;12:726-734. © 2016 SETAC.

As one of the main forms of reactive nitrogen delivered by anthropogenic sources, atmospheric emissions of nitrogen oxides and their subsequent deposition has significantly perturbed the natural nitrogen cycle in sensitive receiving ecosystems worldwide. In North America, despite of decades of increasingly stringent regulations of emissions, decreases in the deposition of nitrogen oxides were not observed until the turn of the century. Analysis of available deposition data and trends at various spatial scales revealed that the decrease took place at a continental scale, but is particularly evident in the eastern side of the continent, where there was an unprecedented 50 % decrease in deposition. The magnitude, timing and geographical extension of the observed changes in deposition resulted from a combination of successfully and relatively coordinated application of emission controls in major contributing regions and increasingly lower amounts of nitrogen oxides being transported from source to receptor areas, thereby extending the effects of emission controls over large geographical scales.

Author Posting. © Ecological Society of America, 2016. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Frontiers in Ecology and the Environment 14 (2016): 200-208, doi:10.1002/fee.1262.

Water quality in mangrove estuaries within Caroni Swamp, Trinidad is impaired by a combination of recent increases in nitrogen loads and lingering effects of a series of reclamation efforts that reduced tidal exchanges and fostered low oxygen and high ammonium concentrations, conditions that are relatively unusual for estuaries. Concentrations of available nitrogen diminish down-estuary, with an overall within-estuary interception of about 25% of total dissolved nitrogen. Caroni Swamp remains a productive mangrove environment, and a tourist attraction, in spite of failed and continuing reclamation efforts and increased N loads, a demonstration of remarkable resilience. Developing ecosystem-based management to support that resilience will benefit from improved understanding of processes involved in nitrogen retention and losses, consideration of the consequences in intensifying land use on contributing watersheds and plans to ease tidal water exchanges and diminish extent of shallow and stagnant areas.

During recent years, rapid seasonal growth of macroalgae covered extensive areas within the Yellow Sea, developing the world’s most spatially extensive “green tide”. The remarkably fast accumulation of macroalgal biomass is the joint result of high nitrogen supplies in Yellow Sea waters, plus ability of the macroalgae to optionally use C4 photosynthetic pathways that facilitate rapid growth. Stable isotopic evidence shows that the high nitrogen supply is derived from anthropogenic sources, conveyed from watersheds via river discharges, and by direct atmospheric deposition. Wastewater and manures supply about half the nitrogen used by the macroalgae, fertiliser and atmospheric deposition each furnish about a quarter of the nitrogen in macroalgae. The massive green tides affecting the Yellow Sea are likely to increase, with significant current and future environmental and human consequences. Addressing these changing trajectories will demand concerted investment in new basic and applied research as the basis for developing management policies.

Salt marshes are important coastal environments that provide key ecological services. As sea level rise has accelerated globally, concerns about the ability of salt marshes to survive submergence are increasing. Previous estimates of likely survival of salt marshes were based on ratios of sea level rise to marsh platform accretion. Here we took advantage of an unusual, long-term (1979–2015), spatially detailed comparison of changes in a representative New England salt marsh to provide an empirical estimate of habitat losses based on actual measurements. We show prominent changes in habitat mosaic within the marsh, consistent and coincident with increased submergence and coastal erosion. Model results suggest that at current rates of sea level rise, marsh platform accretion, habitat loss, and with the limitation of the widespread “coastal squeeze”, the entire ecosystem might disappear by the beginning of the next century, a fate that might be likely for many salt marshes elsewhere. Meta-analysis of available data suggests that 40 to 95% of the world's salt marshes will be submerged, depending on whether sea level rise remains at current or reaches anticipated rates for the end of this century.

Sinorhizobium fredii HH103 is a fast-growing rhizobial strain infecting a broad range of legumes including both American and Asiatic soybeans. In this work, we present the sequencing and annotation of the HH103 genome (7.25 Mb), consisting of one chromosome and six plasmids and representing the structurally most complex sinorhizobial genome sequenced so far. Comparative genomic analyses of S. fredii HH103 with strains USDA257 and NGR234 showed that the core genome of these three strains contains 4,212 genes (61.7% of the HH103 genes). Synteny plot analysis revealed that the much larger chromosome of USDA257 (6.48 Mb) is colinear to the HH103 (4.3 Mb) and NGR324 chromosomes (3.9 Mb). An additional region of the USDA257 chromosome of about 2 Mb displays similarity to plasmid pSfHH103e. Remarkable differences exist between HH103 and NGR234 concerning nod genes, flavonoid effect on surface polysaccharide production, and quorum-sensing systems. Furthermore a number of protein secretion systems have been found. Two genes coding for putative type III–secreted effectors not previously described in S. fredii, nopI and gunA, have been located on the HH103 genome. These differences could be important to understand the different symbiotic behavior of S. fredii strains HH103, USDA257, and NGR234 with soybean.

Nitrogen (N) supply by atmospheric deposition, wastewater, and fertilizers controls estuarine eutrophication. In New England, atmospheric N loads recently decreased by 50% and land-derived contributions rose about 80%, owing to national-scale emission controls and local urban development. The decrease in atmospheric deposition was large enough to balance increases in land-derived N loads, so total N loads to Waquoit Bay estuaries in Cape Cod did not change significantly between 1990 and 2014. Unchanged N regimes were corroborated by finding no differences in estuarine nutrient concentrations and macrophyte biomass between pre-2005 and in 2015. Coastal zones, subject to reasonably rapid changes in global and local driver variables, will require that assessment and management of eutrophication include adaptive strategies that capture effects of changing baselines. Management initiatives will be constrained by spatial scale of driver variables: local efforts may address wastewater and fertilizer N sources, but atmospheric sources require national or international attention.

A decision support framework for the management of lagoon ecosystems was tested using four European Lagoons: Ria de Aveiro (Portugal), Mar Menor (Spain), Tyligulskyi Liman (Ukraine) and Vistula Lagoon (Poland/Russia). Our aim was to formulate integrated management recommendations for European lagoons. To achieve this we followed a DPSIR (Drivers-Pressures-State Change-Impacts-Responses) approach, with focus on integrating aspects of human wellbeing, welfare and ecosystem sustainability. The most important drivers in each lagoon were identified, based on information gathered from the lagoons’ stakeholders, complemented by scientific knowledge on each lagoon as seen from a land-sea perspective. The DPSIR cycles for each driver were combined into a mosaic-DPSIR conceptual model to examine the interdependency between the multiple and interacting uses of the lagoon. This framework emphasizes the common links, but also the specificities of responses to drivers and the ecosystem services provided. The information collected was used to formulate recommendations for the sustainable management of lagoons within a Pan-European context. Several common management recommendations were proposed, but specificities were also identified. The study synthesizes the present conditions for the management of lagoons, thus analysing and examining the activities that might be developed in different scenarios, scenarios which facilitate ecosystem protection without compromising future generations.

We formulate fuel-optimal conflict-free aircraft trajectory planning as a hybrid optimal control problem. The discrete modes of the hybrid system capture the air traffic procedures for conflict resolution, e.g., speed and turn advisories. To solve problems of realistic dimensions arising from air traffic sector planning, we formulate a numerically tractable approach to solve the hybrid optimal control problem. The approach is based on introducing binary functions for each mode, relaxing the binary functions and including a penalty term on the relaxation. The transformed and discretized problem is a nonlinear program. We use the approach on a realistic case study with seven aircraft within an air traffic control sector, in which we find minimum-fuel conflict-free trajectories. Paper supported by the Spanish Ministry of Economy and Competitiveness via project TRA2014-58413-C2-2-R.

Boron (B) deficiency negatively affects legume–rhizobia symbiotic interactions and the development of N2-fixing nodules. Many described alterations are related to plant-derived carbohydrates involved in plant–microbe interactions; however, the effects of B on the bacterial polysaccharides that are crucial for correct symbiosis are unknown. Exopolysaccharide (EPS) production in several rhizobial strains grown in B-free media was analyzed following acetone extraction and silver-stained electrophoretic profiles of lipopolysaccharide (LPS). Moreover, the effects of B deficiency and mutations of the pathogenesis-related ABR17 protein on rhizobia cell surface polysaccharides on legume root colonization, nodulation, nitrogen fixation, and induction in pea nodules were investigated. B-deficiency led to a 65–80 % reduction in the amount of EPS and to modifications of LPS in all strains tested. B-deficient rhizobia were not affected in the degree of adsorption to roots. However, nodulation and nitrogen fixation were reduced or inhibited by B starvation or in plants inoculated with EPS or LPS defective mutants, and ABR17 was induced. The results provide evidence that B is important for production of rhizobia cell surface polysaccharides essential to establish a symbiotic rather than a pathogenic-like interaction, and for development of the N2-fixing legume root nodule.

El cáncer cérvicouterino (CaCu) es la segunda causa de muerte por cáncer en mujeres de todo el mundo, a pesar de la implementación de la citología de cérvix para su prevención. Esto se debe a la baja sensibilidad y especificidad de la prueba, lo cual apoya a un cambio urgente en la forma de tamizaje para su detección. Ahora se sabe que la infección persistente por virus del papiloma humano de alto riesgo (HR-HPV) es la causa de la totalidad de los casos de CaCu. En la actualidad se están utilizando vacunas frente a dos (Bivalente: HPV-16 y HPV-18) o cuatro (Tetravalente: HPV-6 HPV-11, HPV-16 y HPV-18) de las cepas de HR-HPV que causan la mayoría de los casos de CaCu. El propósito de este artículo es proporcionar una revisión de las características principales del virus y de los mecanismos que se echan a andar bajo la infección persistente de las células cervicales, lo cual conduce a la proliferación desordenada y a la malignización de las células infectadas. Es necesario que el virus se integre al genoma de la célula epitelial para que inicie la expresión de las oncoproteínas virales E6 y E7 lo cual conducirá al desarrollo del CaCu. Cervical cancer (CC) is the second cause of death for cancer in women worldwide in spite of the implementation of cervix cytology screenings for its prevention. The low sensibility and specificity of the test reduce the potential benefits of these screenings and supports urgent improvements in early detection tests for CC. It is now known that persistent infection with the high-risk human papiloma virus (HR-HPV) is the causal agent of almost all cases of CC. HR-HPV vaccines effective against two (Bivalent: HPV-16 and HPV-18) or four (Tetravalent: HPV-6 HPV-11, HPV-16 and HPV-18) strains that are responsible of the majority of the CC cases have been licensed in several countries. The present study aims to provide a review of the principal characteristics of the HR-HPV virus and of the mechanisms that take to the persistent infection of the cervical cells leading to abnormal proliferation and malignancy. It is necessary that the virus integrates into the genome of the epithelial cell to initiates the expression of the E6 and E7 viral oncoproteins which will lead to the development of the CC.

Behavioural responses are linked to complex biochemical and physiologic changes and may act as sensitive indicators of the sublethal effects of pollutants. This article investigates changes in the locomotor activity rhythms of the amphipod Gammarus aequicauda exposed to cadmium (Cd) as a model to study the effect of pollutants on an ecologically important species. Under a 12:12 h light-to-dark cycle, G. aequicauda showed a strict nocturnal rhythm, with 90.2±0.4% of their total daily activity occurring during the night. Under constant darkness, circadian rhythms persisted for 10 days, with a mean periodicity of 24.32 h, thus confirming endogenous control. Exposure to sublethal concentrations of Cd (0.16, 0.20, 0.24, and 0.28 mg l(-1)) did not change the nocturnal activity patterns of G. aequicauda, although their swimming activity during the night was significantly decreased by exposure to concentrations of 0.24 and 0.28 mg Cd l(-1). In conclusion, locomotor activity bioassays using the amphipod G. aequicauda appeared to be a sensitive indicator of Cd contamination, and sensitivity and tolerance to Cd in short-term bioassays may depend on the time of the day tests are carried out. These results provide further support for the idea that behavioural end points in amphipods are useful indicators of pollutant exposure and that future studies should take circadian rhythms into consideration.

Eutrophication is widely recognised as one of the major menaces to coastal environments, particularly enclosed bays and lagoons. Although there is a general understanding of the consequences of eutrophication in these systems, there is a lack of sufficient knowledge concerning biotic feedbacks that influence eutrophication patterns and the resistance capacity of coastal environments. In this paper, the isotope ratios of main producers and consumers of a Mediterranean lagoon were examined in order to elucidate the fate of anthropogenic inputs from the main watercourse flowing into the lagoon. The results of the study of stable isotope data in the Mar Menor lagoon reflected that the whole benthic community plays an important role as a natural 'filter' that removes excess nutrients from the water column and stores them in the sediments, thereby enhancing lagoon resistance to eutrophication.

Coastal zones are widely recognised as being particularly vulnerable to future environmental change. Although a significant number of previous papers warn of an increasing tendency in the appearance of eutrophication processes in such systems, very few papers have evaluated the influence of global climate change on eutrophication. In the Mar Menor lagoon (SE Spain), the high biomass of the main primary producer, Caulerpa prolifera Forsskal (Lamououx), covers most of the bottom, and has probably increased the resistance of the lagoon to eutrophication processes through the high uptake of nutrients from the water column and their retention in the sediments, avoiding high phytoplankton densities. Nevertheless, if climate change predictions become true, the current status of the lagoon is likely to collapse, since future environmental conditions could make C. prolifera unable to reach values of net photosynthesis greater than zero, and eutrophication processes are expected to appear. 2008 Elsevier Ltd. All rights reserved.

Two food webs from the Mar Menor coastal lagoon, differing in the distance from the desert-stream through which mining wastes were discharged, were examined by reference to essential (Zn and Cu) and non-essential (Pb and Cd) metal concentrations and stable isotopes content (C and N). The partial extraction technique applied, which reflects the availability of metals to organisms after sediment ingestion, showed higher bioavailable metal concentrations in sediments from the station influenced by the mining discharges, in agreement with the higher metal concentrations observed in organisms, which in many cases exceeded the regulatory limits established in Spanish legislation concerning seafood. Spatial differences in essential metal concentrations in the fauna suggest that several organisms are exposed to metal levels above their regulation capacity. Differences in isotopic composition were found between both food webs, the wadi-influenced station showing higher delta(15)N values and lower delta(13)C levels, due to the discharge of urban waste waters and by the entrance of freshwater and allochthonous marsh plants. The linear-regressions between trophic levels (as indicated by delta(15)N) and the metal content indicated that biomagnification does not occur. In the case of invertebrates, since the "handle strategy" of the species and the physiological requirements of the organisms, among other factors, determine the final concentration of a specific element, no clear relationships between trophic level and the metal content are to be expected. For their part, fish communities did not show clear patterns in the case of any of the analyzed metals, probably because most fish species have similar metal requirements, and because biological factors also intervened. Finally, since the study deals with metals, assumptions concerning trophic transfer factors calculation may not be suitable since the metal burden originates not only from the prey but also from adsorption over the body surfaces and seawater ingestion.

The environmental impact of two fish farms was assessed by larval toxicity bioassays using the sea urchin Paracetrotus lividus . Larval toxicity bioassays have become important for regulatory and monitoring programs, largely because they are assumed to be good indicators of ecological damage to benthic infaunal communities. The study was conducted in two Mediterranean fish farms which produce gilthead sea bream ( Sparus aurata ) and tuna ( Tunna tuna ), respectively. The data obtained from sediment toxicity tests and the physico–chemical characteristics of sediment were examined in two farming production periods to determine the relationships between toxicity and sediment impact. In the gilthead sea bream fish farm, only the sampling stations located at 0 and 35 m were classified as toxic (significant differences from control, p Sea urchin larval toxicity was significantly correlated with sulphides and seasonally, with total ammonia nitrogen in both fish farms. The results reported here are promising and indicate that embryo–larval bioassays with the sea urchin P. lividus represent a sensitive tool for describing the environmental impact of fish farming.

Historical mining activities have led to the presence of enormous quantities of mining wastes, which cover large extensions of the Cartagena-La Union mining district (SE, Spain). In the present work, we study the pulse entrance of mining wastes through two temporary streams (wadis) into the Mar Menor coastal lagoon in two torrential rain events and during a dry period. The characteristics of the runoff pointed to the generation of acid mine drainages in wastes, the acidified stormwater runoff loaded with particulate and dissolved heavy metals causing toxicity in the lagoon waters. The dissolved metals, which mainly affected the sampling stations located close to the wadi discharges, were rapidly eliminated from the water column, whereas the particulate metals were transported further and affected a wider area. Finally, both particulate and dissolved metals are eliminated from the water column and are accumulated in the sediments of the lagoon. The results of the water toxicity tests using sea-urchin embry...

Recent findings have shown that photosynthesis in the skin of the seed of Posidonia oceanica enhances seedling growth. The seagrass genus Posidonia is found only in two distant parts of the world, the Mediterranean Sea and southern Australia. This fact led us to question whether the acquisition of this novel mechanism in the evolution of this seagrass was a pre-adaptation prior to geological isolation of the Mediterranean from Tethys Sea in the Eocene. Photosynthetic activity in seeds of Australian species of Posidonia is still unknown. This study shows oxygen production and respiration rates, and maximum PSII photochemical efficiency (Fv : Fm) in seeds of two Australian Posidonia species (P. australis and P. sinuosa), and compares these with previous results for P. oceanica. Results showed relatively high oxygen production and respiratory rates in all three species but with significant differences among them, suggesting the existence of an adaptive mechanism to compensate for the relatively high oxygen demands of the seeds. In all cases maximal photochemical efficiency of photosystem II rates reached similar values. The existence of photosynthetic activity in the seeds of all three species implicates that it was an ability probably acquired from a common ancestor during the Late Eocene, when this adaptive strategy could have helped Posidonia species to survive in nutrient-poor temperate seas. This study sheds new light on some aspects of the evolution of marine plants and represents an important contribution to global knowledge of the paleogeographic patterns of seagrass distribution.

© 2015 PNAS. An artificial increase of cyclic diguanylate (c-di-GMP) levels in Sinorhizobium meliloti 8530, a bacterium that does not carry known cellulose synthesis genes, leads to overproduction of a substance that binds the dyes Congo red and calcofluor. Sugar composition and methylation analyses and NMR studies identified this compound as a linear mixed-linkage (1→3)(1→4)-β-D-glucan (ML β-glucan), not previously described in bacteria but resembling ML β-glucans found in plants and lichens. This unique polymer is hydrolyzed by the specific endoglucanase lichenase, but, unlike lichenan and barley glucan, it generates a disaccharidic →4)-β-DGlcp-(1→3)-β-D-Glcp-(1→ repeating unit. A two-gene operon bgsBA required for production of this ML β-glucan is conserved among several genera within the order Rhizobiales, where bgsA encodes a glycosyl transferase with domain resemblance and phylogenetic relationship to curdlan synthases and to bacterial cellulose synthases. ML β-glucan synthesis is subjected to both transcriptional and posttranslational regulation. bgsBA transcription is dependent on the exopolysaccharide/quorum sensing ExpR/SinI regulatory system, and posttranslational regulation seems to involve allosteric activation of the ML β-glucan synthase BgsA by c-di-GMP binding to its C-terminal domain. To our knowledge, this is the first report on a linear mixed-linkage (1→3)(1→4)-β-glucan produced by a bacterium. The S. meliloti ML β-glucan participates in bacterial aggregation and biofilm formation and is required for efficient attachment to the roots of a host plant, resembling the biological role of cellulose in other bacteria., We thank J. Nogales for Sme expR and sinI derivatives; M. J. Pérez-Mendoza, University of Granada, and I. Rodríguez-García, University of Almería, for help with initial chemical analyses; T. Felipe-Reyes and D. Rodríguez-Carbonell (Estación Experimental del Zaidín, EEZ) for excellent technical assistance; S. Muñoz for help with competitive nodulation; A. Olmedilla, EEZ, and G. Martín, University of Malaga, for help with scanning microscopy; J. Düvel, Helmholtz Centre for Infection Research, for assistance with dot blot assays and for providing cloned PA3353; and Centro de Investigación Tecnología e Innovación de la Universidad de Sevilla for support with NMR studies. This work was supported by Grant BIO2011-23032 from the Ministerio de Economía y Competitividad and Grant P10-CVI-5800 from the Junta de Andalucía, both cofinanced by the European Fund for Economic and Regional Development, and by Consejo Superior de Investigaciones Cientificas (CSIC) Grant 201440E026. D.P.-M. was supported by a Junta de Ampliación de Estudios (JAE)-doc CSIC contract and later by Grants P10-CVI-5800 and 201440E026; L.R.-J. was supported by a JAE-Pre fellowship; and G.d.A.F. was supported by a contract associated with Grant P10-CVI-5800.

Sinorhizobium meliloti produces an exopolysaccharide called succinoglycan that plays a critical role in promoting symbiosis with its host legume, alfalfa ( Medicago sativa ). We performed a transposon mutagenesis and screened for mutants with altered succinoglycan production and a defect in symbiosis. In this way, we identified a putative two-component histidine kinase associated with a PAS sensory domain, now designated CbrA ( c alcofluor- b right r egulator A ). The cbrA ::Tn 5 mutation causes overproduction of succinoglycan and results in increased accumulation of low-molecular-weight forms of this exopolysaccharide. Our results suggest the cbrA ::Tn 5 allele leads to this succinoglycan phenotype through increased expression of exo genes required for succinoglycan biosynthesis and modification. Interestingly, CbrA-dependent regulation of exo and exs genes is observed almost exclusively during stationary-phase growth. The cbrA ::Tn 5 mutant also has an apparent cell envelope defect, based on increased sensitivity to a number of toxic compounds, including the bile salt deoxycholate and the hydrophobic dye crystal violet. Growth of the cbrA mutant is also slowed under oxidative-stress conditions. The CbrA-regulated genes exsA and exsE encode putative inner membrane ABC transporters with a high degree of similarity to lipid exporters. ExsA is homologous to the Escherichia coli MsbA protein, which is required for lipopolysacharide transport, while ExsE is a member of the eukaryotic family of ABCD/hALD peroxisomal membrane proteins involved in transport of very long-chain fatty acids, which are a unique component of the lipopolysaccharides of alphaproteobacteria. Thus, CbrA could play a role in regulating the lipopolysaccharide or lipoprotein components of the cell envelope.

The Mar Menor is a Mediterranean coastal lagoon of high conservation interest, but highly threatened by non-point pollution derived from agricultural lands. This is the first comprehensive study that evaluates the inputs into the Mar Menor from a drainage channel and the Albujon wadi, the main watercourse, and their influence on the trophic state of the lagoon. Discharge variation during the study period was closely related to the precipitation pattern. Suspended sediments and particulate organic matter loads greatly increased with flash floods. Nitrate concentrations, too, increased after heavy autumn rains through washing of the nitrates accumulated in soils, although no significant correlations were found between nitrate concentrations and precipitation or discharge. The nitrate load depended on several factors including the intensity and frequency of precipitation, and the nitrates accumulated in soils as a result of fertilisation. Phosphate concentrations decreased with higher flows. The total input into the lagoon from the two discharges estimated for the period September 2002–October 2003 were 10,142 t.yr−1of suspended sediments, 389 t.yr−1 of particulate organic matter, 2,010 t.yr−1 of dissolved inorganic nitrogen (93 % as NO−3) and 178 t.yr−1 of soluble reactive phosphorus. The Albujon wadi exported about 80% of the N load and 70% of the P load. Higher flows contributed approximately 80% of the total discharge and nutrient loads, 99% of suspended sediment and 88% of the particulate organic matter. Mean suspended solids and nutrient concentrations in the lagoon followed a spatial pattern, decreasing with distance from the mouth of the Albujon wadi. Water nitrate and phosphate concentrations in the Mar Menor lagoon were lower than reference limits for eutrophic conditions, except after heavy rains. Nutrient concentrations were positively correlated with precipitation variables and particulate and nutrient inputs. Phosphorus was the most limiting nutrient in the Mar Menor, the DIN:SRP ratios found being higher than the Redfield ratio on all sampling dates. Phytoplankton bloom in the lagoon was only found next to the Albujon mouth during late summer and extending 5000 m into the lagoon in autumn as a consequence of large freshwater discharge caused by flash floods. Around 53.6% of the variation in chlorophyll a in the lagoon was explained by the NH4 and NO3 inputs and distance from the Albujon mouth. A good deal of P input into the lagoon is retained in the sediments, supporting a high biomass of the benthic macroalga Caulerpa prolifera in spring and summer.

1.As the interest of divers in exploring marine protected areas grows, so does their impact on sensitive marine organisms and communities. This situation has led managers to adopt a variety of measures to manage scuba diving in marine reserves. However, if marine areas need to be managed and protected from the adverse effects of human activities, then the characterization of marine habitats and the communities they contain, along with the potential effects of scuba diving, will need to be evaluated on scientific lines. 2.To this end, the use of benthic mapping, together with an evaluation of community vulnerability, constitutes a complementary tool for managing scuba diving, as is demonstrated in the present study. 3.The identification and evaluation of the different communities observed in Cabo de Palos-Islas Hormigas Marine Reserve enables managers to propose different measures for controlling potential diver impact and also for evaluating the effects of these measures, thus reducing the degradation of the benthic organisms and communities, benefiting the local tourism industry and allowing a more sustainable use of the marine reserve resources. Copyright © 2006 John Wiley & Sons, Ltd.

The aim of the present study was to check the usefulness of the benthic biotic indices proposed for application in the European water framework directive (WFD 2000/60/EC) for the ecological quality classification of coastal water bodies, together with some other benthic methodologies used in different countries of the world. The different approaches were applied in two marine ecosystems affected by the same heavy metal contamination source, coastal waters off Portman and the Mar Menor coastal lagoon, both in SE Spain. Two marine biotic indices proposed for application in the Directive (AMBI and BENTIX) were used, together with community descriptors (abundance, Shannon–Wiener diversity, Margalef’s species richness, Pielou’s evenness and Simpson’s Dominance), the relative benthic index (RBI) and the abundance-biomass comparison method (ABC). Water-sediment interface toxicity bioassays using sea urchin embryos and sediment metal analysis served to check the classifications obtained. The classical community descriptors pointed to a progressive variation in benthic communities along the metal contamination gradient of Portman, but, they did not correctly characterize the environmental status of the lagoon stations. Although the RBI was the index that best classified the sites according to their degree of pollution, the selection of indicator species can bias the results. Since the AMBI, the BENTIX and the ABC method are based on the pollution resulting from organic enrichment, their application in the case of purely toxic pollution may not be successful, as was found to be the case in these two mining-polluted ecosystems. Therefore, the development of new indicator lists according to the type of pollutant may serve to improve the results obtained with organic enrichment-based indices when studying other kinds of disturbance. Finally, we found the toxicity tests to be useful tools for the environmental assessment of aquatic ecosystems, and recommend their inclusion in the WFD.

In the Mar Menor lagoon (SE Spain) recent changes in the nearby agricultural practices, from extensive dry crop farming to intensively irrigated crops, have increased nutrient and particulate inputs through the principal watercourse that flows into the lagoon, the Albujon wadi. The concentration of nutrients and suspended sediments in the waters has risen, increasing phytoplankton densities and diminishing water column transparency. As a result of these environmental changes, the traditional main macrophyte of the Mar Menor, Cymodocea nodosa (Ucria) Ascherson, has been replaced by the macroalga Caulerpa prolifera (Forsskal) Lamouroux creating changes in the sediment characteristics with profound consequences to benthic communities and also to local fishing and tourism. In the study area, seagrass respiration exceeded photosynthesis while the macroalga presented positive rates of net photosynthesis. C. prolifera is better adapted to these new conditions of light and nutrient concentration and has expanded its distribution, occupying most of the bottom of the lagoon and restricting C. nodosa to small patches in very shallow areas, where plant growth is not limited by light and no C. prolifera can be found because of photoinhibition and emersion stress.

The colonization ability of Pseudomonas fluorescens F113rif in alfalfa rhizosphere and its interactions with the alfalfa microsymbiont Sinorhizobium meliloti EFB1 has been analyzed. Both strains efficiently colonize the alfalfa rhizosphere in gnotobiotic systems and soil microcosms. Colonization dynamics of F113rif on alfalfa were similar to other plant systems previously studied but it is displaced by S. meliloti EFB1, lowering its population by one order of magnitude in co-inoculation experiments. GFP tagged strains used to study the colonization patterns by both strains indicated that P. fluorescens F113rif did not colonize root hairs while S. meliloti EFB1 extensively colonized this niche. Inoculation of F113rif had a deleterious effect on plants grown in gnotobiotic systems, possibly because of the production of HCN and the high populations reached in these systems. This effect was reversed by co-inoculation. Pseudomonas fluorescens F113 derivatives with biocontrol and bioremediation abilities have been developed in recent years. The results obtained support the possibility of using this bacterium in conjunction with alfalfa for biocontrol or rhizoremediation technologies.

When grown under standard conditions, Sinorhizobium meliloti EFB1 simultaneously produces two acidic exopolysaccharides, succinoglycan and galactoglucan, yielding very mucoid colonies. In this strain, MucR is essential for galactoglucan synthesis. A mutation in the mucS gene resulted in less mucoid colonies than in the wild-type EFB1. This mucS¯ strain was complemented to the wild-type phenotype by the cloned mucS gene, indicating that mucS is necessary for a wild-type level of galactoglucan production. Reverse transcription-polymerase chain reaction analysis of exp genes, which encode the pathway for galactoglucan production, in EFB1 and in the mutants affected in mucS, mucR, and both genes simultaneously, showed that MucS is a transcriptional activator of the exp genes but does not affect its own transcription. Furthermore, MucR is necessary for mucS transcriptional activation. As introduction of a cloned mucS gene in a mucR¯ strain yielded colonies less mucoid than the wild type, MucR could also activate exp genes transcription through other pathways. Deletion analysis of the expE promoter showed a region important for transcription and MucS activation. This region, containing a palindrome, is present in the putative expA, expC, expD, and expE promoters but not in the mucS promoter, suggesting that it is the target for MucS. A mucR¯mucS¯ mutant, which does not produce galactoglucan, was impaired in competitive nodulation of alfalfa in soil microcosms, indicating another possible role for this exopolysaccharide in symbiosis.

Media facades are becoming part of our urban landscapes, challenging media artists and designers to create content for them. The diversity of resolution and spatial properties of these facades hasn't stopped content creators to adapt their projects to multiple media facades with significant different resolution, shapes, surroundings and social environment. \ In this paper we introduce Puzzle Facade as an example of an urban technological intervention that has a strong connection with the spatial properties of the media facade it was conceived for, the media facade of the Ars Electronica Center.

Sinorhizobium meliloti can produce two types of acidic exopolysaccharides, succinoglycan and galactoglucan, that are interchangeable for infection of alfalfa nodules. Strain SU47 and derivatives produce only succinoglycan, unless it grows under phosphate limitation or carries a mutation in either of two regulatory loci, mucR or expR. It has been proposed that MucR acts as a transcriptional repressor that blocks the expression of the exp genes responsible for galactoglucan production. Strain EFB1 simultaneously produces both exopolysaccharides. Heterologous expression of lacZ transcriptional fusions of the expE promoters has shown that genetic background is more important that promoter sequence for exp gene expression, since expE promoters from both strains are expressed at high level in EFB1 and not in SU47. We have found that mucR is present in mucoid and nonmucoid strains, and in EFB1 differs from SU47 in only one conservative amino acid change. MucR proteins from both strains are interchangeable. An mucR mutant of EFB1 cannot produce galactoglucan and does not express mucS.

Sinorhizobium fredii HH103 is a fast-growing rhizobial strain that is able to nodulate legumes that develop determinate nodules, e.g., soybean, and legumes that form nodules of the indeterminate type. Here we present the genome of HH103, which consists of one chromosome and five plasmids with a total size of 7.22 Mb.

We present a two player installation game called The Maze EV. The object of the game is for one player to try to escape a maze, before the time runs out, while their opponent creates and modifies that maze in real-time. During game-play, the creation of the maze happens through the use of a tangible interface. The fact that the maze designer is able to modify the structure of the maze during the game gives the game a unique and dynamic feel.

Human activities in coastal areas have increased the occurrence of eutrophication events, especially in vulnerable ecosystems such as coastal lagoons. Although we have a general knowledge of the consequences of eutrophication in these ecosystems, some efforts need to be made to understand biotic feedbacks that could modify the response of the environment to nutrient enrichment. The plant-mediated ‘coastal filter’ is one of the main factors that determine lagoonal efficiency in processing excess nutrients. In this context, the present paper examined the relative contribution of benthic macrofauna to the ‘coastal filter’ of a Mediterranean lagoon. The analysis of macrofaunal assemblages in the Mar Menor lagoon led to a clear differentiation between shallow areas of net nutrient recycling and exportation and deeper areas of net retention. These differences enhance nutrient removal from the water column, thus increasing the ecosystem’s resistance to eutrophication.

Glycine max (soybean) plants can be nodulated by fast-growing rhizobial strains of the genus Sinorhizobium as well as by slow-growing strains clustered in the genus Bradyrhizobium. Fast-growing rhizobia strains with different soybean cultivar specificities have been isolated from Chinese soils and from other geographical regions. Most of these strains have been clustered into the species Sinorhizobium fredii. The S. fredii strain HH103 was isolated from soils of Hubei province, Central China and was first described in 1985. This strain is capable to nodulate American and Asiatic soybean cultivars and many other different legumes and is so far the best studied fast-growing soybean-nodulating strain. Additionally to the chromosome S. fredii HH103 carries five indigenous plasmids. The largest plasmid (pSfrHH103e) harbours genes for the production of diverse surface polysaccharides, such as exopolysaccharides (EPS), lipopolysaccharides (LPS), and capsular polysaccharides (KPS). The second largest plasmid (pSfrHH103d) is a typical symbiotic plasmid (pSym), carrying nodulation and nitrogen fixation genes. The present mini review focuses on symbiotic properties of S. fredii HH103, in particular on nodulation and surface polysaccharides aspects. The model strain S. fredii HH103 was chosen for genomic sequencing, which is currently in progress. First analyses of the draft genome sequence revealed an extensive synteny between the chromosomes of S. fredii HH103 and Rhizobium sp. NGR234.

68 pages, 8 figures, 1 table, 3 additional files.-- Provisional PDF., [Background] The bacterial Hfq protein is able to interact with diverse RNA molecules, including regulatory small non-coding RNAs (sRNAs), and thus it is recognized as a global post-transcriptional regulator of gene expression. Loss of Hfq has an extensive impact in bacterial physiology which in several animal pathogens influences virulence. Sinorhizobium meliloti is a model soil bacterium known for its ability to establish a beneficial nitrogen-fixing intracellular symbiosis with alfalfa. Despite the predicted general involvement of Hfq in the establishment of successful bacteria-eukaryote interactions, its function in S. meliloti has remained unexplored., [Results] Two independent S. meliloti mutants, 2011-3.4 and 1021Deltahfq, were obtained by disruption and deletion of the hfq gene in the wild-type strains 2011 and 1021, respectively, both exhibiting similar growth defects as free-living bacteria. Transcriptomic profiling of 1021Deltahfq revealed a general down-regulation of genes of sugar transporters and some enzymes of the central carbon metabolism, whereas transcripts specifying the uptake and metabolism of nitrogen sources (mainly amino acids) were more abundant than in the wild-type strain. Proteomic analysis of the 2011-3.4 mutant independently confirmed these observations. Symbiotic tests showed that lack of Hfq led to a delayed nodulation, severely compromised bacterial competitiveness on alfalfa roots and impaired normal plant growth. Furthermore, a large proportion of nodules (55%-64%) elicited by the 1021Deltahfq mutant were non-fixing, with scarce content in bacteroids and signs of premature senescence of endosymbiotic bacteria. RT-PCR experiments on RNA from bacteria grown under aerobic and microoxic conditions revealed that Hfq contributes to regulation of nifA and fixK1/K2, the genes controlling nitrogen fixation, although the Hfq-mediated regulation of fixK is only aerobiosis dependent. Finally, we found that some of the recently identified S. meliloti sRNAs co-inmunoprecipitate with a FLAG-epitope tagged Hfq protein., [Conclusions] Our results support that the S. meliloti RNA chaperone Hfq underlies the control of central metabolic pathways in free-living bacteria and influences rhizospheric competence, survival of the microsymbiont within the nodule cells and nitrogen fixation during the symbiotic interaction with its legume host alfalfa. The identified S. meliloti Hfq-binding sRNAs are predicted to participate in the Hfq regulatory network., This work was funded by the Spanish Ministerio de Ciencia e Innovación (Projects AGL2006-12466 and AGL2009-07925) and Junta de Andalucía (Project CV1-01522). Work at RR laboratory has been funded by the Comunidad de Madrid MICROAMBIENTE-CM Program. OTQ is recipient of a FPI Fellowship from the Spanish Ministerio de Ciencia e Innovación.

Megaplasmid pSymB of the nitrogen-fixing symbiont Sinorhizobium meliloti , implicated in adaptation to hyperosmotic stress, contains 11 gene clusters that apparently encode surface polysaccharides. However, only 2 of these clusters, containing the exo and exp genes, have been associated with the synthesis of the acidic exopolysaccharides succinoglycan and galactoglucan, respectively. The functions of the other 9 clusters remain unsolved. The involvement of one of those regions, pSymB cluster 3, on surface polysaccharide synthesis and its possible implication in osmoadaptation were investigated. In silico analysis of cluster 3 showed that it putatively encodes for the synthesis and transport of a methylated surface polysaccharide. Mutants affected in this cluster were symbiotically effective but showed defects in growth under saline and nonsaline osmotic stress. The gene SMb21071, encoding a putative initiating glycosyltransferase, is transcriptionally induced under hyperosmotic conditions. Sodium dodecyl sulfate – polyacrylamide gel electrophoresis and silver staining showed that osmotic stresses changed the profiles of surface polysaccharides of wild-type and mutants strains in different ways. The overall results suggest that cluster 3 is important for growth under saline stress and essential for growth under nonsaline hyperosmotic stress, and it appears to be implicated in maintaining and (or) modifying surface polysaccharides in response to osmotic stress.

Sinorhizobium fredii HH103 produces cyclic β glucans (CG) composed of 18 to 24 glucose residues without or with 1-phosphoglycerol as the only substituent. The S. fredii HH103-Rifr cgs gene (formerly known as ndvB) was sequenced and mutated with the lacZ-gentamicin resistance cassette. Mutant SVQ562 did not produce CG, was immobile, and grew more slowly in the hypoosmotic GYM medium, but its survival in distilled water was equal to that of HH103-Rifr. Lipopolysaccharides and K-antigen polysaccharides produced by SVQ562 were not apparently altered. SVQ562 overproduced exopolysaccharides (EPS) and its exoA gene was transcribed at higher levels than in HH103-Rifr. In GYM medium, the EPS produced by SVQ562 was of higher molecular weight and carried higher levels of substituents than that produced by HH103-Rifr. The expression of the SVQ562 cgs∷lacZ fusion was influenced by the pH and the osmolarity of the growth medium. The S. fredii cgs mutants SVQ561 (carrying cgs∷Ω) and SVQ562 only formed pseudonodules on Glycine max (determinate nodules) and on Glycyrrhiza uralensis (indeterminate nodules). Although nodulation factors were detected in SVQ561 cultures, none of the cgs mutants induced any macroscopic response in Vigna unguiculata roots. Thus, the nodulation process induced by S. fredii cgs mutants is aborted at earlier stages in V. unguiculata than in Glycine max.

Pseudomonas fluorescens F113 is motile by means of type b flagella. Analysis of the region encoding the synthesis of the flagellar filament has shown a transcriptional organization different from that of type a flagella. Additionally to the promoters driving fliC , fliD , and fleQ expression, we have found promoters upstream of the flaG gene and the fliST operon. These promoters were functional in vivo. Both promoters have been mapped and appear to be dependent on the vegetative sigma factor and independent of FleQ, the master regulator of flagellum synthesis.

Portman Bay, southeast Spain, contains the most seriously metal-contaminated sediments of the Mediterranean Sea. From 1958 to 1991, approximately 50 million tons of mine tailings were dumped into the bay, completely filling up the bay and dispersing over an extensive area of the continental platform and continental slope. The objective of our study was to characterize the nature and extent of metal contamination and the responses of natural communities to it and to assess the toxicity of the sediment deposits 10 years after mining had ceased. We studied the physical and chemical characteristics of the sediments and toxicity (of the porewater and sediment–water interface) using two sea urchin species ( Arbacia lixula and Paracentrotus lividus ). Metal bioavailability and patterns of macroinvertebrate community composition along the contamination gradient were also studied. Univariate and multivariate analyses showed positive correlation between the sediment metal concentrations associated to the all biological effects (sea urchins toxicity tests and benthic indices). The effects of sediment contamination on the benthic community structure are visible among sampling stations.

The type IV secretion system (T4SS) of the plant intracellular symbiont Sinorhizobium meliloti 1021 is required for conjugal transfer of DNA. However, it is not required for host invasion and persistence, unlike the T4SSs of closely related mammalian intracellular pathogens. A comparison of the requirement for a bacterial T4SS in plant versus animal host invasion suggests an important difference in the intracellular niches occupied by these bacteria.