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Sample records for promoting industrial symbiosis

  1. Applying industrial symbiosis to chemical industry: A literature review

    NASA Astrophysics Data System (ADS)

    Cui, Hua; Liu, Changhao

    2017-08-01

    Chemical industry plays an important role in promoting the development of global economy and human society. However, the negative effects caused by chemical production cannot be ignored, which often leads to serious resource consumption and environmental pollution. It is essential for chemical industry to achieve a sustainable development. Industrial symbiosis is one of the key topics in the field of industrial ecology and circular economy, which has been identified as a creative path leading to sustainability. Based on an extensively searching for literatures on linking industrial symbiosis with chemical industry, this paper aims to review the literatures which involves three aspects: (1) economic and environmental benefits achieved by chemical industry through implementing industrial symbiosis, (2) chemical eco-industrial parks, (3) and safety issues for chemical industry. An outlook is also provided. This paper concludes that: (1) chemical industry can achieve both economic and environmental benefits by implementing industrial symbiosis, (2) establishing eco-industrial parks is essential for chemical industry to implement and improve industrial symbiosis, and (3) there is a close relationship between IS and safety issues of chemical industry.

  2. Determinant factors of industrial symbiosis: greening Pasir Gudang industrial park

    NASA Astrophysics Data System (ADS)

    Teh, B. T.; Ho, C. S.; Matsuoka, Y.; Chau, L. W.; Gomi, K.

    2014-02-01

    Green industry has been identified as an important element in attaining greater sustainability. It calls for harmonizing robust economic growth with environment protection. Industries, particularly in developing and transitional nations such as Malaysia, are in need of a reform. Many experts and international organizations suggest the concept of industrial symbiosis. Mainly, there are successful cases of industrial symbiosis practices around the world. However, there are numerous cases of failure too. As industrial symbiosis is an emerging new approach, with a short history of two decades, a lot of researches are generally focused on narrow context and technical details. There is a lack of concerted efforts to look into the drivers and barriers of industrial symbiosis across different cases. This paper aims to examine the factors influencing the development of industrial symbiosis from various countries to supports such networks to evolve in Pasir Gudang. The findings show institution, law and regulation, finance, awareness and capacity building, technology, research and development, information, collaboration, market, geography proximity, environmental issues and industry structure affect the formation of industrial symbiosis.

  3. Network analysis of eight industrial symbiosis systems

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Zheng, Hongmei; Shi, Han; Yu, Xiangyi; Liu, Gengyuan; Su, Meirong; Li, Yating; Chai, Yingying

    2016-06-01

    Industrial symbiosis is the quintessential characteristic of an eco-industrial park. To divide parks into different types, previous studies mostly focused on qualitative judgments, and failed to use metrics to conduct quantitative research on the internal structural or functional characteristics of a park. To analyze a park's structural attributes, a range of metrics from network analysis have been applied, but few researchers have compared two or more symbioses using multiple metrics. In this study, we used two metrics (density and network degree centralization) to compare the degrees of completeness and dependence of eight diverse but representative industrial symbiosis networks. Through the combination of the two metrics, we divided the networks into three types: weak completeness, and two forms of strong completeness, namely "anchor tenant" mutualism and "equality-oriented" mutualism. The results showed that the networks with a weak degree of completeness were sparse and had few connections among nodes; for "anchor tenant" mutualism, the degree of completeness was relatively high, but the affiliated members were too dependent on core members; and the members in "equality-oriented" mutualism had equal roles, with diverse and flexible symbiotic paths. These results revealed some of the systems' internal structure and how different structures influenced the exchanges of materials, energy, and knowledge among members of a system, thereby providing insights into threats that may destabilize the network. Based on this analysis, we provide examples of the advantages and effectiveness of recent improvement projects in a typical Chinese eco-industrial park (Shandong Lubei).

  4. Academia-industry symbiosis in organic chemistry.

    PubMed

    Michaudel, Quentin; Ishihara, Yoshihiro; Baran, Phil S

    2015-03-17

    Collaboration between academia and industry is a growing phenomenon within the chemistry community. These sectors have long held strong ties since academia traditionally trains the future scientists of the corporate world, but the recent drastic decrease of public funding is motivating the academic world to seek more private grants. This concept of industrial "sponsoring" is not new, and in the past, some companies granted substantial amounts of money per annum to various academic institutions in exchange for prime access to all their scientific discoveries and inventions. However, academic and industrial interests were not always aligned, and therefore the investment has become increasingly difficult to justify from industry's point of view. With fluctuating macroeconomic factors, this type of unrestricted grant has become more rare and has been largely replaced by smaller and more focused partnerships. In our view, forging a partnership with industry can be a golden opportunity for both parties and can represent a true symbiosis. This type of project-specific collaboration is engendered by industry's desire to access very specific academic expertise that is required for the development of new technologies at the forefront of science. Since financial pressures do not allow companies to spend the time to acquire this expertise and even less to explore fundamental research, partnering with an academic laboratory whose research is related to the problem gives them a viable alternative. From an academic standpoint, it represents the perfect occasion to apply "pure science" research concepts to solve problems that benefit humanity. Moreover, it offers a unique opportunity for students to face challenges from the "real world" at an early stage of their career. Although not every problem in industry can be solved by research developments in academia, we argue that there is significant scientific overlap between these two seemingly disparate groups, thereby presenting an

  5. Academia–Industry Symbiosis in Organic Chemistry

    PubMed Central

    2015-01-01

    Conspectus Collaboration between academia and industry is a growing phenomenon within the chemistry community. These sectors have long held strong ties since academia traditionally trains the future scientists of the corporate world, but the recent drastic decrease of public funding is motivating the academic world to seek more private grants. This concept of industrial “sponsoring” is not new, and in the past, some companies granted substantial amounts of money per annum to various academic institutions in exchange for prime access to all their scientific discoveries and inventions. However, academic and industrial interests were not always aligned, and therefore the investment has become increasingly difficult to justify from industry’s point of view. With fluctuating macroeconomic factors, this type of unrestricted grant has become more rare and has been largely replaced by smaller and more focused partnerships. In our view, forging a partnership with industry can be a golden opportunity for both parties and can represent a true symbiosis. This type of project-specific collaboration is engendered by industry’s desire to access very specific academic expertise that is required for the development of new technologies at the forefront of science. Since financial pressures do not allow companies to spend the time to acquire this expertise and even less to explore fundamental research, partnering with an academic laboratory whose research is related to the problem gives them a viable alternative. From an academic standpoint, it represents the perfect occasion to apply “pure science” research concepts to solve problems that benefit humanity. Moreover, it offers a unique opportunity for students to face challenges from the “real world” at an early stage of their career. Although not every problem in industry can be solved by research developments in academia, we argue that there is significant scientific overlap between these two seemingly disparate

  6. Understanding resilience in industrial symbiosis networks: insights from network analysis.

    PubMed

    Chopra, Shauhrat S; Khanna, Vikas

    2014-08-01

    Industrial symbiotic networks are based on the principles of ecological systems where waste equals food, to develop synergistic networks. For example, industrial symbiosis (IS) at Kalundborg, Denmark, creates an exchange network of waste, water, and energy among companies based on contractual dependency. Since most of the industrial symbiotic networks are based on ad-hoc opportunities rather than strategic planning, gaining insight into disruptive scenarios is pivotal for understanding the balance of resilience and sustainability and developing heuristics for designing resilient IS networks. The present work focuses on understanding resilience as an emergent property of an IS network via a network-based approach with application to the Kalundborg Industrial Symbiosis (KIS). Results from network metrics and simulated disruptive scenarios reveal Asnaes power plant as the most critical node in the system. We also observe a decrease in the vulnerability of nodes and reduction in single points of failure in the system, suggesting an increase in the overall resilience of the KIS system from 1960 to 2010. Based on our findings, we recommend design strategies, such as increasing diversity, redundancy, and multi-functionality to ensure flexibility and plasticity, to develop resilient and sustainable industrial symbiotic networks.

  7. Discaria trinervis - Frankia symbiosis promotion by saprophytic actinomycetes.

    PubMed

    Solans, Mariana

    2007-06-01

    The influence of saprophytic actinomycetes strains on the Discaria trinervis - Frankia actinorhizal symbiosis was investigated. Three strains out of 122 isolated from the rhizosphere and rhizoplane of D. trinervis with multiple enzymatic activities, were selected for plant growth experiments: Streptomyces (BCRU-MM40), Actinoplanes (BCRU-ME3) and Micromonospora (BCRU-MM18). Inoculated seedlings of Discaria trinervis were grown in glass tubes with vermiculite-sand for 12 weeks. They were inoculated either with a single saprophytic strain or a combination of one or two of them together with the symbiotic N(2) fixing strain Frankia BCU110501. The saprophytic strains were applied in two experimental series, i.e. mycelium + supernatant simultaneously or mycelium and supernatant (growth medium free of cells) separately. Micromonospora strain MM18 showed a direct promotion effect on shoot growth, when plants were inoculated with mycelium and supernatant together. Streptomyces strain MM40 and Actinoplanes strain ME3 promoted the actinorhizal symbiosis with Frankia and consequently the development of plant shoots, when supernatant was involved as inoculum. It is supposed, that the strains MM18, MM40 and ME3 produce bioactive metabolites, which are released into the culture medium. The saprophytic strains studied could be considered as "promoting or helper rhizoactinomycetes" of the actinorhizal plant D. trinervis.

  8. Harm promotion: observations on the symbiosis between government and private industries in Australasia for the development of highly accessible gambling markets.

    PubMed

    Livingstone, Charles; Adams, Peter J

    2011-01-01

    To illustrate ways in which industry control over the gambling market and its regulatory system have enabled rapid proliferation in gambling consumption and harm. To discuss the relationship between government regulation and the accessibility, marketing and technologies of electronic gambling machines in Australia and New Zealand. The regulatory framework for gambling in both countries has encouraged highly accessible,regressively distributed and heavily marketed high-impact electronic gambling machines. This framework has developed in large part through the conjunction of government revenue needs and the adaptation of a folk model of gambling appropriated by gambling businesses and engineered to incorporate a discourse that legitimate their gambling businesses. Governments should be encouraged to invest in 'upstream' public health strategies that contain the economic and social drivers for intensifying gambling consumption. One key aspect involves questioning the most suitable scale, location and marketing of gambling operations, and the reliance of government on gambling revenues (whether directly or as substitution for other government expenditure). Technological solutions to disrupt the development of obsessive gambling habits are also available and are likely to reduce gambling-related harm.

  9. Pilot testing model to uncover industrial symbiosis in Brazilian industrial clusters.

    PubMed

    Saraceni, Adriana Valélia; Resende, Luis Mauricio; de Andrade Júnior, Pedro Paulo; Pontes, Joseane

    2017-04-01

    The main objective of this study was to create a pilot model to uncover industrial symbiosis practices in Brazilian industrial clusters. For this purpose, a systematic revision was conducted in journals selected from two categories of the ISI Web of Knowledge: Engineering, Environmental and Engineering, Industrial. After an in-depth revision of literature, results allowed the creation of an analysis structure. A methodology based on fuzzy logic was applied and used to attribute the weights of industrial symbiosis variables. It was thus possible to extract the intensity indicators of the interrelations required to analyse the development level of each correlation between the variables. Determination of variables and their weights initially resulted in a framework for the theory of industrial symbiosis assessments. Research results allowed the creation of a pilot model that could precisely identify the loopholes or development levels in each sphere. Ontology charts for data analysis were also generated. This study contributes to science by presenting the foundations for building an instrument that enables application and compilation of the pilot model, in order to identify opportunity to symbiotic development, which derives from "uncovering" existing symbioses.

  10. Emergy-based assessment on industrial symbiosis: a case of Shenyang Economic and Technological Development Zone.

    PubMed

    Geng, Yong; Liu, Zuoxi; Xue, Bing; Dong, Huijuan; Fujita, Tsuyoshi; Chiu, Anthony

    2014-12-01

    Industrial symbiosis is the sharing of services, utility, and by-product resources among industries. This is usually made in order to add value, reduce costs, and improve the environment, and therefore has been taken as an effective approach for developing an eco-industrial park, improving resource efficiency, and reducing pollutant emission. Most conventional evaluation approaches ignored the contribution of natural ecosystem to the development of industrial symbiosis and cannot reveal the interrelations between economic development and environmental protection, leading to a need of an innovative evaluation method. Under such a circumstance, we present an emergy analysis-based evaluation method by employing a case study at Shenyang Economic and Technological Development Zone (SETDZ). Specific emergy indicators on industrial symbiosis, including emergy savings and emdollar value of total emergy savings, were developed so that the holistic picture of industrial symbiosis can be presented. Research results show that nonrenewable inputs, imported resource inputs, and associated services could be saved by 89.3, 32.51, and 15.7 %, and the ratio of emergy savings to emergy of the total energy used would be about 25.58 %, and the ratio of the emdollar value of total emergy savings to the total gross regional product (GRP) of SETDZ would be 34.38 % through the implementation of industrial symbiosis. In general, research results indicate that industrial symbiosis could effectively reduce material and energy consumption and improve the overall eco-efficiency. Such a method can provide policy insights to industrial park managers so that they can raise appropriate strategies on developing eco-industrial parks. Useful strategies include identifying more potential industrial symbiosis opportunities, optimizing energy structure, increasing industrial efficiency, recovering local ecosystems, and improving public and industrial awareness of eco-industrial park policies.

  11. Design for sustainability of industrial symbiosis based on emergy and multi-objective particle swarm optimization.

    PubMed

    Ren, Jingzheng; Liang, Hanwei; Dong, Liang; Sun, Lu; Gao, Zhiqiu

    2016-08-15

    Industrial symbiosis provides novel and practical pathway to the design for the sustainability. Decision support tool for its verification is necessary for practitioners and policy makers, while to date, quantitative research is limited. The objective of this work is to present an innovative approach for supporting decision-making in the design for the sustainability with the implementation of industrial symbiosis in chemical complex. Through incorporating the emergy theory, the model is formulated as a multi-objective approach that can optimize both the economic benefit and sustainable performance of the integrated industrial system. A set of emergy based evaluation index are designed. Multi-objective Particle Swarm Algorithm is proposed to solve the model, and the decision-makers are allowed to choose the suitable solutions form the Pareto solutions. An illustrative case has been studied by the proposed method, a few of compromises between high profitability and high sustainability can be obtained for the decision-makers/stakeholders to make decision.

  12. Beyond the Boundary: Science, Industry, and Managing Symbiosis

    ERIC Educational Resources Information Center

    Hansen, Birgitte Gorm

    2011-01-01

    Whether celebratory or critical, STS research on science-industry relations has focused on the blurring of boundaries and hybridization of codes and practices. However, the vocabulary of boundary and hybrid tends to reify science and industry as separate in the attempt to map their relation. Drawing on interviews with the head of a research center…

  13. Beyond the Boundary: Science, Industry, and Managing Symbiosis

    ERIC Educational Resources Information Center

    Hansen, Birgitte Gorm

    2011-01-01

    Whether celebratory or critical, STS research on science-industry relations has focused on the blurring of boundaries and hybridization of codes and practices. However, the vocabulary of boundary and hybrid tends to reify science and industry as separate in the attempt to map their relation. Drawing on interviews with the head of a research center…

  14. Methods for assessing the energy-saving efficiency of industrial symbiosis in industrial parks.

    PubMed

    Li, Wenfeng; Cui, Zhaojie; Han, Feng

    2015-01-01

    The available energy resources are being depleted worldwide. Industrial symbiosis (IS) provides a promising approach for increasing the efficiency of energy utilization, with numerous studies reporting the superiority of this technology. However, studies quantifying the energy-saving efficiency of IS remain insufficient. This paper proposes an index system for the quantitative evaluation of the energy-saving efficiency of IS. Both energy-saving and financial indexes were selected, the former include the IS energy-saving index, the contribution rate of energy saved through IS, fractional energy savings, and cut rate of energy consumption per total output value; and the latter include the IS investment payback period, IS input-output ratio, net present value (NPV), and internal rate of return (IRR) of IS. The proposed methods were applied to a case study on the XF Industrial Park (XF IP), in the city of Liaocheng in Shandong Province of China. Three energy-saving channels using IS were found in the XF IP: (a) utilizing the energy of high-temperature materials among industrial processes, (b) recovering waste heat and steam between different processes, and (c) saving energy by sharing infrastructures. The results showed that the energy efficiency index of IS was 0.326, accounting for 34.6% of the comprehensive energy-saving index in 2011, and the fractional energy-savings were 12.42%. The index of energy consumption per total industrial output value varied from 90.9 tce/MRMB to 51.6 tce/MRMB. Thus, the cut rate of energy consumption per total industrial output value was 43.42%. The average values of the IS input-output ratio was 406.2 RMB/tce, 57.2% lower than the price of standard coal. Static investment payback period in the XF IP was 8.5 months, indicating that the XF IP began to earn profit 8.5 months after the construction of all IS modes. The NVP and IRR of each IS mode in the XF IP were greater than zero, with average values equal to 1,789.96 MRMB and 140

  15. Industrial symbiosis: corn ethanol fermentation, hydrothermal carbonization, and anaerobic digestion.

    PubMed

    Wood, Brandon M; Jader, Lindsey R; Schendel, Frederick J; Hahn, Nicholas J; Valentas, Kenneth J; McNamara, Patrick J; Novak, Paige M; Heilmann, Steven M

    2013-10-01

    The production of dry-grind corn ethanol results in the generation of intermediate products, thin and whole stillage, which require energy-intensive downstream processing for conversion into commercial animal feed products. Hydrothermal carbonization of thin and whole stillage coupled with anaerobic digestion was investigated as alternative processing methods that could benefit the industry. By substantially eliminating evaporation of water, reductions in downstream energy consumption from 65% to 73% were achieved while generating hydrochar, fatty acids, treated process water, and biogas co-products providing new opportunities for the industry. Processing whole stillage in this manner produced the four co-products, eliminated centrifugation and evaporation, and substantially reduced drying. With thin stillage, all four co-products were again produced, as well as a high quality animal feed. Anaerobic digestion of the aqueous product stream from the hydrothermal carbonization of thin stillage reduced chemical oxygen demand (COD) by more than 90% and converted 83% of the initial COD to methane. Internal use of this biogas could entirely fuel the HTC process and reduce overall natural gas usage. Copyright © 2013 Wiley Periodicals, Inc.

  16. Industrial and urban symbiosis in Japan: analysis of the Eco-Town Program 1997-2006.

    PubMed

    Van Berkel, Rene; Fujita, Tsuyoshi; Hashimoto, Shizuka; Geng, Yong

    2009-03-01

    Japan's Eco-Town Program spearheaded in Japan the integration of Industrial Symbiosis and Urban Symbiosis, seeking to maximise the economic and environmental benefit from close geographic proximity of industrial and urban areas, through the use of previously discarded commercial, municipal and industrial waste materials in industrial applications. The program established 26 Eco-Towns around Japan. Approximately 1.65 billion USD was invested in 61 innovative recycling projects, with an average government subsidy of 36%. In addition at least 107 other recycling facilities have been constructed without government subsidy. 14 Eco-Towns primarily contributed to improving industry's productivity, whilst 10 Eco-Towns primarily contributed to improving environmental amenity. In 16 Eco-Towns the private sector was the most important actor supporting local government in the realisation of the Eco-Town, whilst in 9 Eco-Towns this was civil society. The availability of investment subsidies, the coming into force of ambitious recycling legislation with quantified, product-specific targets, access to the significant technological resources of the private sector, and widespread recognition of the urgency to act on environmental issues, all contributed to the success of the Eco-Town Program.

  17. Assessment of life cycle environmental benefits of an industrial symbiosis cluster in China.

    PubMed

    Yu, Fei; Han, Feng; Cui, Zhaojie

    2015-04-01

    Reusing industrial waste may have impressive potential environmental benefits, especially in terms of the total life cycle, and life cycle assessment (LCA) has been proved to be an effective method to evaluate industrial symbiosis (IS). Circular economy and IS have been developed for decades and have been successful in China. However, very few studies about the environmental benefit assessment of IS applied by LCA in China have been conducted. In the current article, LCA was used to evaluate the environmental benefits and costs of IS, compared with a no-IS scenario for four environmental impact categories. The results showed that four environmental benefits were avoided by the 11 symbiosis performances, namely, 41.6 thousand TJ of primary energy, 4.47 million t CO2e of greenhouse gasses, 19.7 thousand t SO2e of acidification, and 81.1 t PO4(3+)e of eutrophication. Among these IS performances, the comprehensive utilization of red mud produced the most visible benefit. The results also present that energy conservation was the distinctive feature of IS in China.

  18. A diverse host thrombospondin-type-1 repeat protein repertoire promotes symbiont colonization during establishment of cnidarian-dinoflagellate symbiosis.

    PubMed

    Neubauer, Emilie-Fleur; Poole, Angela Z; Neubauer, Philipp; Detournay, Olivier; Tan, Kenneth; Davy, Simon K; Weis, Virginia M

    2017-05-08

    The mutualistic endosymbiosis between cnidarians and dinoflagellates is mediated by complex inter-partner signaling events, where the host cnidarian innate immune system plays a crucial role in recognition and regulation of symbionts. To date, little is known about the diversity of thrombospondin-type-1 repeat (TSR) domain proteins in basal metazoans or their potential role in regulation of cnidarian-dinoflagellate mutualisms. We reveal a large and diverse repertoire of TSR proteins in seven anthozoan species, and show that in the model sea anemone Aiptasia pallida the TSR domain promotes colonization of the host by the symbiotic dinoflagellate Symbiodinium minutum. Blocking TSR domains led to decreased colonization success, while adding exogenous TSRs resulted in a 'super colonization'. Furthermore, gene expression of TSR proteins was highest at early time-points during symbiosis establishment. Our work characterizes the diversity of cnidarian TSR proteins and provides evidence that these proteins play an important role in the establishment of cnidarian-dinoflagellate symbiosis.

  19. Quantifying the Contribution of Urban-Industrial Efficiency and Symbiosis to Deep Decarbonization: Impact of 637 Chinese Cities

    NASA Astrophysics Data System (ADS)

    Ramaswami, A.; Tong, K.; Fang, A.; Lal, R.; Nagpure, A.; Li, Y.; Yu, H.; Jiang, D.; Russell, A. G.; Shi, L.; Chertow, M.; Wang, Y.; Wang, S.

    2016-12-01

    Urban activities in China contribute significantly to global greenhouse gas (GHG) emissions and to local air pollution-related health risks. Co-location analysis can help inform the potential for energy- and material-exchanges across homes, businesses, infrastructure and industries co-located in cities. Such co-location dependent urban-industrial symbiosis strategies offer a new pathway toward urban energy efficiency and health that have not previously been quantified. Key examples includes the use of waste industrial heat in other co-located industries, and in residential-commercial district heating-cooling systems of cities. To quantify the impact of these strategies: (1) We develop a new data-set of 637 Chinese cities to assess the potential for efficiency and symbiosis across co-located homes, businesses, industries and the energy and construction sectors in the different cities. (2) A multi-scalar urban systems model quantifies trans-boundary CO2 impacts as well as local health benefits of these uniquely urban, co-location-dependent strategies. (3) CO2 impacts are aggregated across the 637 Chinese cities (home to 701 million people) to quantify national CO2 mitigation potential. (4) The local health benefits are modeled specific to each city and mapped geospatially to identify areas where co-benefits between GHG mitigation and health are maximized. Results: A first order conservative analysis of co-location dependent urban symbiosis indicates potential for reducing 6% of China's national total CO2 emissions in a relatively short time period, yielding a new pathway not previously considered in China's energy futures models. The magnitude of these reductions (6%) was similar in magnitude to sector specific industrial, power sector and buildings efficiency strategeies that together contributed 9% CO2 reduction aggregated across the nation. CO2 reductions mapped to the 637 cities ranged from <1% to 40%, depending upon co-location patterns, climate and other

  20. Quantifying the total environmental impacts of an industrial symbiosis - a comparison of process-, hybrid and input-output life cycle assessment.

    PubMed

    Mattila, Tuomas J; Pakarinen, Suvi; Sokka, Laura

    2010-06-01

    Industrial symbiosis, representing resource sharing and byproduct use among colocated firms, is a key concept of industrial ecology. Local co-operation in industrial symbioses can reduce raw material use and waste disposal, but material and energy flows extending outside symbiosis boundaries can cause considerable environmental impacts. These external impacts are often ignored in industrial symbiosis studies. In this study, we compared process, hybrid and input-output life cycle assessment (LCA) approaches in quantifying the overall environmental impacts of a forest industrial symbiosis, situated in Kymenlaakso, Finland. Conclusions from an earlier process-LCA were strengthened by the use of hybrid-LCA as local emissions were found to cause less than half of the global impacts. In some impact categories, the whole impact was caused by supply chain emissions (land use, metal depletion and ozone depletion). The cutoff in process-LCA was found to be less than 25%, except in metal depletion and terrestrial ecotoxicity. Input-output LCA approximated hybrid-LCA results well in most impact categories, but seriously underestimated land use and overestimated terrestrial ecotoxicity. Based on the results we conclude, that input-output based LCA can be used to analyze the global impacts of an industrial symbiosis, but a careful interpretation of the results is necessary in order to understand the influence of aggregation and allocation.

  1. Strategies for sustainable development of industrial park in Ulsan, South Korea--from spontaneous evolution to systematic expansion of industrial symbiosis.

    PubMed

    Park, Hung-Suck; Rene, Eldon R; Choi, Soo-Mi; Chiu, Anthony S F

    2008-04-01

    The Korea National Cleaner Production Center (KNCPC) affiliated to the Korea Institute of Industrial Technology (KITECH) has started a 15 year, 3-phase EIP master plan with the support of Ministry of Commerce, Industry, and Energy (MOCIE). A total of 6 industrial parks, including industrial parks in Ulsan city, known as the industrial capital of South Korea, are planning projects to find the feasibility of shifting existing industrial parks to eco-industrial parks. The basic survey shows that Ulsan industrial complex has been continuously evolving from conventional industrial complexes to eco-industrial parks by spontaneous industrial symbiosis. This paper describes the Korean national policies and the developmental activities of this vision to drive the global trend of innovation for converting the existing industrial parks to eco-industrial parks through inter-industry waste, energy, and material exchange in Ulsan Industrial complexes. In addition, the primary and supportive components of the Ulsan EIP pilot project, which will be implemented for 5 years is elaborated with its schedules and economic benefits.

  2. Designing symbiosis.

    PubMed

    Hosoda, Kazufumi; Yomo, Tetsuya

    2011-01-01

    Organisms rarely live as isolated species and usually show symbiosis in nature. As natural selection is not simple in symbiosis, the establishment and development of symbiosis is still unclear. Insight can be gained by not only retracing the history of well-developed natural symbiotic relationships, but also by observing the development of nascent symbiosis. By using synthetic symbiosis composed of two previously noninteracting populations, we can observe the establishment and its development. We have recently simulated the establishment of nascent symbiosis using two genetically engineered auxotrophic strains of Escherichia coli. One strain, 10 h after mixing with the partner strain, began to oversupply metabolites essential for the partner's growth, eventually leading to continual growth of both strains. Transcriptome analysis revealed that the oversupply was accompanied by global metabolic changes. This study demonstrated that an organism has the potential to adapt to the first encounter with another organism to establish symbiosis.

  3. Medicago sativa--Sinorhizobium meliloti Symbiosis Promotes the Bioaccumulation of Zinc in Nodulated Roots.

    PubMed

    Zribi, Kais; Nouairi, Issam; Slama, Ines; Talbi-Zribi, Ons; Mhadhbi, Haythem

    2015-01-01

    In this study we investigated effects of Zn supply on germination, growth, inorganic solutes (Zn, Ca, Fe, and Mg) partitioning and nodulation of Medicago sativa This plant was cultivated with and without Zn (2 mM). Treatments were plants without (control) and with Zn tolerant strain (S532), Zn intolerant strain (S112) and 2 mM urea nitrogen fertilisation. Results showed that M. sativa germinates at rates of 50% at 2 mM Zn. For plants given nitrogen fertilisation, Zn increased plant biomass production. When grown with symbionts, Zn supply had no effect on nodulation. Moreover, plants with S112 showed a decrease of shoot and roots biomasses. However, in symbiosis with S532, an increase of roots biomass was observed. Plants in symbiosis with S. meliloti accumulated more Zn in their roots than nitrogen fertilised plants. Zn supply results in an increase of Ca concentration in roots of fertilised nitrogen plants. However, under Zn supply, Fe concentration decreased in roots and increased in nodules of plants with S112. Zn supply showed contrasting effects on Mg concentrations for plants with nitrogen fertilisation (increase) and plants with S112 (decrease). The capacity of M. sativa to accumulate Zn in their nodulated roots encouraged its use in phytostabilisation processes.

  4. Schoolyard Symbiosis.

    ERIC Educational Resources Information Center

    Allard, David W.

    1996-01-01

    Discusses different types of symbiosis--mutualism, commensalism, and parasitism--and examples of each type including lichens, legumes, mistletoe, and epiphytes. Describes how teachers can use these examples in the study of symbiosis which allows teachers to focus on many basic concepts in evolution, cell biology, ecology, and other fields of…

  5. Schoolyard Symbiosis.

    ERIC Educational Resources Information Center

    Allard, David W.

    1996-01-01

    Discusses different types of symbiosis--mutualism, commensalism, and parasitism--and examples of each type including lichens, legumes, mistletoe, and epiphytes. Describes how teachers can use these examples in the study of symbiosis which allows teachers to focus on many basic concepts in evolution, cell biology, ecology, and other fields of…

  6. Symbiosis with systemic fungal endophytes promotes host escape from vector-borne disease.

    PubMed

    Perez, L I; Gundel, P E; Marrero, H J; Arzac, A González; Omacini, M

    2017-03-18

    Plants interact with a myriad of microorganisms that modulate their interactions within the community. A well-described example is the symbiosis between grasses and Epichloë fungal endophytes that protects host plants from herbivores. It is suggested that these symbionts could play a protective role for plants against pathogens through the regulation of their growth and development and/or the induction of host defences. However, other endophyte-mediated ecological mechanisms involved in disease avoidance have been scarcely explored. Here we studied the endophyte impact on plant disease caused by the biotrophic fungus, Claviceps purpurea, under field conditions through (1) changes in the survival of the pathogen´s resistance structure (sclerotia) during overwintering on the soil surface, and (2) effects on insects responsible for the transportation of pathogen spores. This latter mechanism is tested through a visitor exclusion treatment and the measurement of plant volatile cues. We found no significant effects of the endophyte on the survival of sclerotia and thus on disease inocula. However, both pathogen incidence and severity were twofold lower in endophyte-symbiotic plants than in non-symbiotic ones, though when insect visits were prevented this difference disappeared. Endophyte-symbiotic and non-symbiotic plots presented different emission patterns of volatiles suggesting that they can play a role in this protection. We show a novel indirect ecological mechanism by which endophytes can defend host grasses against diseases through negatively interacting with intermediary vectors of the epidemic process.

  7. The Piriformospora indica effector PIIN_08944 promotes the mutualistic Sebacinalean symbiosis

    PubMed Central

    Akum, Fidele N.; Steinbrenner, Jens; Biedenkopf, Dagmar; Imani, Jafargholi; Kogel, Karl-Heinz

    2015-01-01

    Pathogenic and mutualistic microbes actively suppress plant defense by secreting effector proteins to manipulate the host responses for their own benefit. Current knowledge about fungal effectors has been mainly derived from biotrophic and hemibiotrophic plant pathogenic fungi and oomycetes with restricted host range. We studied colonization strategies of the root endophytic basidiomycete Piriformospora indica that colonizes a wide range of plant species thereby establishing long-term mutualistic relationships. The release of P. indica’s genome helped to identify hundreds of genes coding for candidate effectors and provides an opportunity to investigate the role of those proteins in a mutualistic symbiosis. We demonstrate that the candidate effector PIIN_08944 plays a crucial role during fungal colonization of Arabidopsis thaliana roots. PIIN_08944 expression was detected during chlamydospore germination, and fungal deletion mutants (PiΔ08944) showed delayed root colonization. Constitutive over-expression of PIIN_08944 in Arabidopsis rescued the delayed colonization phenotype of the deletion mutant. PIIN_08944-expressing Arabidopsis showed a reduced expression of flg22-induced marker genes of pattern-triggered immunity (PTI) and the salicylic acid (SA) defense pathway, and expression of PIIN_08944 in barley reduced the burst of reactive oxygen species (ROS) triggered by flg22 and chitin. These data suggest that PIIN_08944 contributes to root colonization by P. indica by interfering with SA-mediated basal immune responses of the host plant. Consistent with this, PIIN_08944-expressing Arabidopsis also supported the growth of the biotrophic oomycete Hyaloperonospora arabidopsidis while growth of the necrotrophic fungi Botrytis cinerea on Arabidopsis and Fusarium graminearum on barley was not affected. PMID:26579156

  8. ANDES TOOLS: Promotional slides for Industrial Clients

    DTIC Science & Technology

    2015-09-03

    Briefing Charts 3. DATES COVERED (From - To) 10 August 2015 – 3 September 2015 4. TITLE AND SUBTITLE ANDES TOOLS: Promotional slides for Industrial...Industrial Clients PA Case Number: #15479; Clearance Date: 9/3/2015 14. ABSTRACT Briefing Charts/Viewgraphs 15. SUBJECT TERMS N/A 16. SECURITY

  9. Pharmacy residents' attitudes toward pharmaceutical industry promotion.

    PubMed

    Ashker, Sumer; Burkiewicz, Jill S

    2007-08-15

    The attitudes of pharmacy residents toward pharmaceutical industry promotion and the perceived effects of such promotion on the knowledge and professional practice of the residents were studied. A questionnaire study of current postgraduate year 1 and postgraduate year 2 pharmacy residents was conducted. Questions were adapted from instruments used in studies of medical student or physician attitudes regarding the pharmaceutical industry. The questionnaire requested demographic information about the resident, information regarding the resident's exposure to specific types of pharmaceutical company-related activities, and the resident's perception of whether the residency program or department had policies or guidelines regarding interactions with the pharmaceutical industry. Questions investigated the attitudes toward pharmaceutical industry promotion and the perceived influence of pharmaceutical industry promotion on the professional knowledge and behavior of the residents. Responses were received from 496 pharmacy residents. Nearly all (89%) residents agreed that pharmaceutical company-sponsored educational events enhance knowledge. Almost half (43%) of the respondents reported that information from educational events influences therapeutic recommendations. One quarter (26%) of the pharmacy residents indicated prior training regarding pharmacist-industry interactions, and most (60%) residents indicated that their institution's residencies or departments have policies regarding interactions with the pharmaceutical industry. Most surveyed pharmacy residents believed that educational events sponsored by pharmaceutical companies enhance knowledge. Respondents whose institutions had policies or who had received training about such events were less likely than other respondents to perceive an influence of the events on their knowledge and behavior.

  10. Saltational symbiosis.

    PubMed

    Sapp, Jan

    2010-09-01

    Symbiosis has long been associated with saltational evolutionary change in contradistinction to gradual Darwinian evolution based on gene mutations and recombination between individuals of a species, as well as with super-organismal views of the individual in contrast to the classical one-genome: one organism conception. Though they have often been dismissed, and overshadowed by Darwinian theory, suggestions that symbiosis and lateral gene transfer are fundamental mechanisms of evolutionary innovation are borne out today by molecular phylogenetic research. It is time to treat these processes as central principles of evolution.

  11. Teaching Symbiosis.

    ERIC Educational Resources Information Center

    Harper, G. H.

    1985-01-01

    Argues that the meaning of the word "symbiosis" be standardized and that it should be used in a broad sense. Also criticizes the orthodox teaching of general principles in this subject and recommends that priority be given to continuity, intimacy, and associated adaptations, rather than to the harm/benefit relationship. (Author/JN)

  12. Health Promotion in Business and Industry.

    ERIC Educational Resources Information Center

    Health Education (Washington D.C.), 1985

    1985-01-01

    Three articles suggest that the roots of health promotion in business and industry extend back into the early twentieth century: (1) "Health Programs of Business Concerns" (Schirmer); (2) "Teach Health, Not Disease" (Bauer); and (3) "A Leader in Health Education: Metropolitan Life Insurance Company" (Means). (CB)

  13. A plant growth-promoting symbiosis between Mycena galopus and Vaccinium corymbosum seedlings.

    PubMed

    Grelet, Gwen-Aëlle; Ba, Ren; Goeke, Dagmar F; Houliston, Gary J; Taylor, Andy F S; Durall, Daniel M

    2017-08-25

    Typically, Mycena species are viewed as saprotrophic fungi. However, numerous detections of Mycena spp. in the roots of green plants suggest that a continuum from saprotrophy to biotrophy could exist. In particular, mycenoid species have repeatedly been found in Ericaceae plant roots. Our study asked whether (1) Mycena species are commonly found in the roots of green Ericaceae plants; (2) Mycena sequences are limited to a single group/lineage within the genus; and (3) a Mycena sp. can behave as a beneficial root associate with a typical ericoid mycorrhizal plant (Vaccinium corymbosum), regardless of how much external labile carbon is available. We detected Mycena sequences in roots of all sampled Ericaceae plants. Our Mycena sequences clustered in four different groups distributed across the Mycena genus. Only one group could be assigned with confidence to a named species (M. galopus). Our Mycena sequences clustered with other Mycena sequences detected in roots of ericoid mycorrhizal plant species collected throughout Europe, America, and Australia. An isolate of M. galopus promoted growth of V. corymbosum seedlings in vitro regardless of external carbon supply in the media. Seedlings inoculated with M. galopus grew as well as those inoculated with the ericoid mycorrhizal fungus Rhizoscyphus ericae. Surprisingly, this M. galopus isolate colonized Vaccinium roots and formed distinctive peg-like structures. Our results suggest that Mycena species might operate along a saprotroph-symbiotic continuum with a range of ericoid mycorrhizal plant species. We discuss our results in terms of fungal partner recruitment by Ericaceae plants.

  14. Symbiosis: An Evolutionary Innovator.

    ERIC Educational Resources Information Center

    Case, Emily

    2003-01-01

    Defines symbiosis and describes the connection between symbiosis and evolution, how it is described in science textbooks, and genetic variability. Discusses educational policy and science curriculum content. (YDS)

  15. AEC to Referee, Not Promote, Industry.

    PubMed

    1971-10-29

    A major turnabout in the attitude of the Atomic Energy Commission toward the nuclear power industry was signaled last week by the ntew AEC chairman James R. Schlesinger. With patrician froideur, Schlesinger informed a mass gathering of the nuclear power industry at Bal Harbour, Florida, that from henceforth the AEC woLuld act as the referee of nuclear power, not its promoter. Saying he would dispense with the "anecdotes and clumsy jests" customary on such occasions, Schlesinger served notice on the nuclear banqueters that their cozy relationship with the AEC was at an end. The industry should not expect the AEC to fight its battles: it should take its own case to the public-as the Sierra Club does. Nor did the AEC intend to bend the rules in industry's favor. "We have had a fair amount of advice on how to evade the clear mandate of the federal courts. It is advice we did not think proper to accept," Schlesinger said. Even on matters of engineering quality, the diners were told they knew full well they had "reason to blush." Roused out of any postprandial euphoria by this glacial disdain, the industry representatives heard the new chairman announce the following radical upheavals in official AEC philosophy.

  16. Promoting sustainable industry through waste minimisation clubs.

    PubMed

    Barclay, S J; Buckley, C A

    2002-01-01

    The concept of waste minimisation clubs was developed in the early 1990s to promote the exchange of experiences between geographically close manufacturers in the implementation of waste minimisation measures. It is a successful approach, resulting not only in a reduction in environmental impact, but also significant financial savings for the companies involved. Two pilot waste minimisation clubs were established in the province of kwaZulu Natal in South Africa in 1998 and 1999, to determine if this approach was a feasible method of promoting sustainable industrial development in South Africa. On conclusion of this project in December 2000, the 20 companies that participated in these clubs had saved a total of US$ 1.7 million, and reduced their water use and effluent discharge by over 2,400 Ml/y.

  17. Engineering the nifH promoter region and abolishing poly-beta-hydroxybutyrate accumulation in Rhizobium etli enhance nitrogen fixation in symbiosis with Phaseolus vulgaris.

    PubMed

    Peralta, Humberto; Mora, Yolanda; Salazar, Emmanuel; Encarnación, Sergio; Palacios, Rafael; Mora, Jaime

    2004-06-01

    Rhizobium etli, as well as some other rhizobia, presents nitrogenase reductase (nifH) gene reiterations. Several R. etli strains studied in this laboratory showed a unique organization and contained two complete nifHDK operons (copies a and b) and a truncated nifHD operon (copy c). Expression analysis of lacZ fusion demonstrated that copies a and b in strain CFN42 are transcribed at lower levels than copy c, although this copy has no discernible role during nitrogen fixation. To increase nitrogenase production, we constructed a chimeric nifHDK operon regulated by the strong nifHc promoter sequence and expressed it in symbiosis with the common bean plant (Phaseolus vulgaris), either cloned on a stably inherited plasmid or incorporated into the symbiotic plasmid (pSym). Compared with the wild-type strain, strains with the nitrogenase overexpression construction assayed in greenhouse experiments had, increased nitrogenase activity (58% on average), increased plant weight (32% on average), increased nitrogen content in plants (15% at 32 days postinoculation), and most importantly, higher seed yield (36% on average), higher nitrogen content (25%), and higher nitrogen yield (72% on average) in seeds. Additionally, expression of the chimeric nifHDK operon in a poly-beta-hydroxybutyrate-negative R. etli strain produced an additive effect in enhancing symbiosis. To our knowledge, this is the first report of increased seed yield and nutritional content in the common bean obtained by using only the genetic material already present in Rhizobium.

  18. Engineering the nifH Promoter Region and Abolishing Poly-β-Hydroxybutyrate Accumulation in Rhizobium etli Enhance Nitrogen Fixation in Symbiosis with Phaseolus vulgaris

    PubMed Central

    Peralta, Humberto; Mora, Yolanda; Salazar, Emmanuel; Encarnación, Sergio; Palacios, Rafael; Mora, Jaime

    2004-01-01

    Rhizobium etli, as well as some other rhizobia, presents nitrogenase reductase (nifH) gene reiterations. Several R. etli strains studied in this laboratory showed a unique organization and contained two complete nifHDK operons (copies a and b) and a truncated nifHD operon (copy c). Expression analysis of lacZ fusion demonstrated that copies a and b in strain CFN42 are transcribed at lower levels than copy c, although this copy has no discernible role during nitrogen fixation. To increase nitrogenase production, we constructed a chimeric nifHDK operon regulated by the strong nifHc promoter sequence and expressed it in symbiosis with the common bean plant (Phaseolus vulgaris), either cloned on a stably inherited plasmid or incorporated into the symbiotic plasmid (pSym). Compared with the wild-type strain, strains with the nitrogenase overexpression construction assayed in greenhouse experiments had, increased nitrogenase activity (58% on average), increased plant weight (32% on average), increased nitrogen content in plants (15% at 32 days postinoculation), and most importantly, higher seed yield (36% on average), higher nitrogen content (25%), and higher nitrogen yield (72% on average) in seeds. Additionally, expression of the chimeric nifHDK operon in a poly-β-hydroxybutyrate-negative R. etli strain produced an additive effect in enhancing symbiosis. To our knowledge, this is the first report of increased seed yield and nutritional content in the common bean obtained by using only the genetic material already present in Rhizobium. PMID:15184121

  19. Heavy metal stress in alders: Tolerance and vulnerability of the actinorhizal symbiosis.

    PubMed

    Bélanger, Pier-Anne; Bellenger, Jean-Philippe; Roy, Sébastien

    2015-11-01

    Alders have already demonstrated their potential for the revegetation of both mining and industrial sites. These actinorhizal trees and shrubs and the actinobacteria Frankia associate in a nitrogen-fixing symbiosis which could however be negatively affected by the presence of heavy metals, and accumulate them. In our hydroponic assay with black alders, quantification of the roots and shoots metal concentrations showed that, in the absence of stress, symbiosis increases Mo and Ni root content and simultaneously decreases Mo shoot content. Interestingly, the Mo shoot content also decreases in the presence of Ni, Cu, Pb, Zn and Cd for symbiotic alders. In symbiotic alders, Pb shoot translocation was promoted in presence of Pb. On the other hand, Cd exclusion in symbiotic root tissues was observed with Pb and Cd. In the presence of symbiosis, only Cd and Pb showed translocation into aerial tissues when present in the nutrient solution. Moreover, the translocation of Ni to shoot was prevented by symbiosis in the presence of Cd, Ni and Pb. The hydroponic experiment demonstrated that alders benefit from the symbiosis, producing more biomass (total, root and shoot) than non nodulated alders in control condition, and in the presence of metals (Cu, Ni, Zn, Pb and Cd). Heavy metals did not reduce the nodule numbers (SNN), but the presence of Zn or Cd did reduce nodule allocation. Our study suggests that the Frankia-alder symbiosis is a promising (and a compatible) plant-microorganism association for the revegetation of contaminated sites, with minimal risk of metal dispersion.

  20. Cell biology of cnidarian-dinoflagellate symbiosis.

    PubMed

    Davy, Simon K; Allemand, Denis; Weis, Virginia M

    2012-06-01

    The symbiosis between cnidarians (e.g., corals or sea anemones) and intracellular dinoflagellate algae of the genus Symbiodinium is of immense ecological importance. In particular, this symbiosis promotes the growth and survival of reef corals in nutrient-poor tropical waters; indeed, coral reefs could not exist without this symbiosis. However, our fundamental understanding of the cnidarian-dinoflagellate symbiosis and of its links to coral calcification remains poor. Here we review what we currently know about the cell biology of cnidarian-dinoflagellate symbiosis. In doing so, we aim to refocus attention on fundamental cellular aspects that have been somewhat neglected since the early to mid-1980s, when a more ecological approach began to dominate. We review the four major processes that we believe underlie the various phases of establishment and persistence in the cnidarian/coral-dinoflagellate symbiosis: (i) recognition and phagocytosis, (ii) regulation of host-symbiont biomass, (iii) metabolic exchange and nutrient trafficking, and (iv) calcification. Where appropriate, we draw upon examples from a range of cnidarian-alga symbioses, including the symbiosis between green Hydra and its intracellular chlorophyte symbiont, which has considerable potential to inform our understanding of the cnidarian-dinoflagellate symbiosis. Ultimately, we provide a comprehensive overview of the history of the field, its current status, and where it should be going in the future.

  1. Cell Biology of Cnidarian-Dinoflagellate Symbiosis

    PubMed Central

    Allemand, Denis; Weis, Virginia M.

    2012-01-01

    Summary: The symbiosis between cnidarians (e.g., corals or sea anemones) and intracellular dinoflagellate algae of the genus Symbiodinium is of immense ecological importance. In particular, this symbiosis promotes the growth and survival of reef corals in nutrient-poor tropical waters; indeed, coral reefs could not exist without this symbiosis. However, our fundamental understanding of the cnidarian-dinoflagellate symbiosis and of its links to coral calcification remains poor. Here we review what we currently know about the cell biology of cnidarian-dinoflagellate symbiosis. In doing so, we aim to refocus attention on fundamental cellular aspects that have been somewhat neglected since the early to mid-1980s, when a more ecological approach began to dominate. We review the four major processes that we believe underlie the various phases of establishment and persistence in the cnidarian/coral-dinoflagellate symbiosis: (i) recognition and phagocytosis, (ii) regulation of host-symbiont biomass, (iii) metabolic exchange and nutrient trafficking, and (iv) calcification. Where appropriate, we draw upon examples from a range of cnidarian-alga symbioses, including the symbiosis between green Hydra and its intracellular chlorophyte symbiont, which has considerable potential to inform our understanding of the cnidarian-dinoflagellate symbiosis. Ultimately, we provide a comprehensive overview of the history of the field, its current status, and where it should be going in the future. PMID:22688813

  2. Department of Industrial Health and Saftey Promotion: Curriculum Plan.

    ERIC Educational Resources Information Center

    Brody, Carmen

    The industrial health and safety promotion curriculum described in this paper is intended for an industrial manufacturing plant employing approximately 10,000 people. The paper begins by describing the plant and the workers for which the curriculum was designed. Next, a rationale for having a Department of Industrial Health and Safety program…

  3. Department of Industrial Health and Saftey Promotion: Curriculum Plan.

    ERIC Educational Resources Information Center

    Brody, Carmen

    The industrial health and safety promotion curriculum described in this paper is intended for an industrial manufacturing plant employing approximately 10,000 people. The paper begins by describing the plant and the workers for which the curriculum was designed. Next, a rationale for having a Department of Industrial Health and Safety program…

  4. How Symbiosis Creates Diversity

    ERIC Educational Resources Information Center

    Lord, Joshua

    2010-01-01

    Diversity in habitats on Earth is astounding--whether on land or in the sea--and this is in part due to symbiosis. The lesson described in this article helps students understand how symbiosis affects different organisms through a fun and engaging game where they match hosts and symbionts based on their respective needs. This 45-minute lesson is…

  5. How Symbiosis Creates Diversity

    ERIC Educational Resources Information Center

    Lord, Joshua

    2010-01-01

    Diversity in habitats on Earth is astounding--whether on land or in the sea--and this is in part due to symbiosis. The lesson described in this article helps students understand how symbiosis affects different organisms through a fun and engaging game where they match hosts and symbionts based on their respective needs. This 45-minute lesson is…

  6. 76 FR 22751 - Softwood Lumber Research, Promotion, Consumer Education and Industry Information Order...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-22

    ... Lumber Research, Promotion, Consumer Education and Industry Information Order; Referendum Procedures... 0581-AD03 Softwood Lumber Research, Promotion, Consumer Education and Industry Information Order... Research, Promotion, Consumer Education and Industry Information Order (Order) is favored by domestic...

  7. Health promotion in the Finnish shipping industry.

    PubMed

    Saarni, H; Laine, M; Niemi, L; Pentti, J

    2001-01-01

    In autumn 1997 a pilot project was started in Finland to develop methods for promoting the health of sailors. Four Finnish shipping companies, (4 cargo ships and 2 passenger-cruise ferries), with altogether 730 sailors participated in the project. Special attention was paid to individuals with health problems and those who generally did not take care of their own health or fitness. Three-quarters of the respondents saw their health as good and one fifth as fair. Thirty-four persons responded that their working capacity was poor. 154 sailors were selected into further physical fitness evaluations. The main task of the project team was to activate sailors to take care of their own health and well-being. The health-promoting activities were directed especially at those persons who needed it. Information lectures concerning healthier eating habits and meals were given. Anti-smoking and anti-alcohol drinking information was given. On board one cruise ferry a project was started on how to react as early as possible to alcohol abuse among seafarers. Courses on shore for sailors were arranged to improve their physical fitness and to increase their resting benefit between working periods at sea. The intervention time was one year. Information about smoking and alcohol led to reduced alcohol consumption. The sailors had started to exercise more often both on board ship and on shore. Those who had increased their physical exercise during free time more often found their own health and working ability to have improved than those who had not changed their exercise habits. It appeared that health intervention projects are really needed especially by older sailors. The results also showed that positive effects could be achieved in the fitness of sailors. Better fitness was good for their health and also increased the work safety.

  8. Tobacco related bar promotions: insights from tobacco industry documents

    PubMed Central

    Katz, S; Lavack, A

    2002-01-01

    Design: Over 2000 tobacco industry documents available as a result of the Master Settlement Agreement were reviewed on the internet at several key web sites using keyword searches that included "bar", "night", "pub", "party", and "club". The majority of the documents deal with the US market, with a minor emphasis on Canadian and overseas markets. Results: The documents indicate that bar promotions are important for creating and maintaining brand image, and are generally targeted at a young adult audience. Several measures of the success of these promotions are used, including number of individuals exposed to the promotion, number of promotional items given away, and increased sales of a particular brand during and after the promotion. Conclusion: Bar promotions position cigarettes as being part of a glamorous lifestyle that includes attendance at nightclubs and bars, and appear to be highly successful in increasing sales of particular brands. PMID:11893819

  9. Avoiding "truth": tobacco industry promotion of life skills training.

    PubMed

    Mandel, Lev L; Bialous, Stella Aguinaga; Glantz, Stanton A

    2006-12-01

    To understand why and how two tobacco companies have been promoting the Life Skills Training program (LST), a school-based drug prevention program recommended by the Centers for Disease Control and Prevention to reduce youth smoking. We analyzed internal tobacco industry documents available online as of October 2005. Initial searches were conducted using the keywords "life skills training," "LST," and "positive youth development." Tobacco industry documents reveal that since 1999, Philip Morris (PM) and Brown and Williamson (B&W) have worked to promote LST and to disseminate the LST program into schools across the country. As part of their effort, the companies hired a public relations firm to promote LST and a separate firm to evaluate the program. The evaluation conducted for the two companies did not show that LST was effective at reducing smoking after the first or second year of implementing the program. Even so, the tobacco companies continued to award grants to schools for the program. PM and B&W's role in promoting LST is part of a public relations strategy to shift the "youth smoking paradigm" away from programs that highlight the tobacco industry's behavior and toward programs in which the industry can be a partner. Individuals and organizations responsible for developing and implementing tobacco control and youth smoking prevention programs should be aware of PM and B&W's role and motivations to encourage the wide-spread adoption of LST in schools.

  10. Strategies for Improving Compliance with Health Promotion Programs in Industry.

    ERIC Educational Resources Information Center

    Feldman, Robert H. L.

    1983-01-01

    Behavioral, educational, and organizational methods for improving the degree to which workers comply with the objectives of industrial health promotion programs are discussed. Compliance can be enhanced through: (1) better program location and scheduling; (2) increased worker satisfaction; (3) use of psychological and educational techniques; and…

  11. Chinese tobacco industry promotional activity on the microblog Weibo.

    PubMed

    Wang, Fan; Zheng, Pinpin; Yang, Dongyun; Freeman, Becky; Fu, Hua; Chapman, Simon

    2014-01-01

    Although China ratified the WHO Framework Convention on Tobacco Control [FCTC] in 2005, the partial ban on tobacco advertising does not cover the internet. Weibo is one of the most important social media channels in China, using a format similar to its global counterpart, Twitter. The Weibo homepage is a platform to present products, brands and corporate culture. There is great potential for the tobacco industry to exploit Weibo to promote products. Seven tobacco industry Weibo accounts that each had more than 5000 fans were selected to examine the content of Weibos established by tobacco companies or their advertising agents. Of the 12073 posts found on the seven accounts, 92.3% (11143) could be classified into six main themes: traditional culture, popular culture, social and business affairs, advertisement, public relations and tobacco culture. Posts under the theme of popular culture accounted for about half of total posts (49%), followed by 'advertisement' and 'tobacco culture' (both at 12%), 'traditional culture' and 'public relations' (both at 11%), and finally 'social and business affairs' (5%). 33% of posts included the words 'cigarette' or 'smoking' and 53% of posts included the tobacco brand name, indicating that tobacco companies carefully construct the topic and content of posts. Weibo is an important new online marketing tool for the Chinese tobacco industry. Tobacco industry use of Weibo to promote brands and normalize smoking subverts China's ratification of the WHO FCTC. Policy to control tobacco promotion needs reforming to address this widespread circumvention of China's tobacco advertising ban.

  12. Tobacco point-of-purchase promotion: examining tobacco industry documents.

    PubMed

    Lavack, Anne M; Toth, Graham

    2006-10-01

    In the face of increasing media restrictions around the world, point-of-purchase promotion (also called point-of-sale merchandising, and frequently abbreviated as POP or POS) is now one of the most important tools that tobacco companies have for promoting tobacco products. Using tobacco industry documents, this paper demonstrates that tobacco companies have used point-of-purchase promotion in response to real or anticipated advertising restrictions. Their goal was to secure dominance in the retail setting, and this was achieved through well-trained sales representatives who offered contracts for promotional incentive programmes to retailers, which included the use of point-of-sale displays and merchandising fixtures. Audit programmes played an important role in ensuring contract enforcement and compliance with a variety of tobacco company incentive programmes. Tobacco companies celebrated their merchandising successes, in recognition of the stiff competition that existed among tobacco companies for valuable retail display space.

  13. Tobacco point‐of‐purchase promotion: examining tobacco industry documents

    PubMed Central

    Lavack, Anne M; Toth, Graham

    2006-01-01

    In the face of increasing media restrictions around the world, point‐of‐purchase promotion (also called point‐of‐sale merchandising, and frequently abbreviated as POP or POS) is now one of the most important tools that tobacco companies have for promoting tobacco products. Using tobacco industry documents, this paper demonstrates that tobacco companies have used point‐of‐purchase promotion in response to real or anticipated advertising restrictions. Their goal was to secure dominance in the retail setting, and this was achieved through well‐trained sales representatives who offered contracts for promotional incentive programmes to retailers, which included the use of point‐of‐sale displays and merchandising fixtures. Audit programmes played an important role in ensuring contract enforcement and compliance with a variety of tobacco company incentive programmes. Tobacco companies celebrated their merchandising successes, in recognition of the stiff competition that existed among tobacco companies for valuable retail display space. PMID:16998172

  14. Symbiosis: Rich, Exciting, Neglected Topic

    ERIC Educational Resources Information Center

    Rowland, Jane Thomas

    1974-01-01

    Argues that the topic of symbiosis has been greatly neglected and underemphasized in general-biology textbooks. Discusses many types and examples of symbiosis, and provides an extensive bibliography of the literature related to this topic. (JR)

  15. Norwegian industry and health promotion 1910-1967.

    PubMed

    Ibsen, H

    1993-01-01

    The development of occupational health services in Norway is explored by making a case study of both a chocolate factory and a cement factory. The study shows how different motives and ideological positions promoted the industrial health service. Prominent among them were a social and political philosophy, those of welfare capitalism, as an alternative to socialism and state policy in building the affluent society and the move toward improvements of production. All leading to a growing interest in the human factor in industry, where the medical officer should help to shape a satisfied, rational and productive worker in a healthy work environment.

  16. Health promoting leadership practices in four Norwegian industries.

    PubMed

    Skarholt, Kari; Blix, Elisabeth H; Sandsund, Mariann; Andersen, Thale K

    2016-12-01

    The aim of this article is to address health promoting leadership; what do leaders actually do to promote health at work? Leadership practice plays a crucial role in the workplace and greatly affects the working environment and working conditions. Through a theoretical and empirical approach, we seek to find characteristics/patterns of health promoting leadership. The definition of health promoting leadership is a democratic and supportive leadership style, where leaders seek to motivate and inspire their employees. The study in this article is based on qualitative research methods. We have investigated and compared leadership practice in four different organizations/industries in Norway: construction, oil and gas, health care and cleaning. These organizations and professions are quite different, and thus leadership must be understood and developed within its context. However, we found some generic characteristics of health promoting leadership: hands-on, accessible, supportive, inclusive and democratic. Current literature only rarely addresses how leadership affects health promotion at work. Consequently, more knowledge is needed about how leaders really succeed in creating healthy workplaces and healthy employees.

  17. Health promotion: what's in it for business and industry?

    PubMed

    Brennan, A J

    1982-01-01

    Health promotion has been linked to improved morale, increased productivity, reduced absenteeism and turnover, more appropriate utilization of medical services and decreased disability and premature death claims due to unhealthy lifestyles. Preliminary data in favor of HPPs are being accumulated. Final proof is not available to "sell" myopic bottom line managers on the concept, however, as Immanuel Kant stated, "It is often necessary to make a decision on the basis of knowledge sufficient for action but insufficient to satisfy the intellect." If techniques can be developed to quantify in economic terms the impact of health promotion in these areas, business and industry will have a profound, hard line reason beyond their genuine interest in the health of their employees, for providing health promotion to employee populations--MONEY.

  18. Chinese Tobacco Industry Promotional Activity on the Microblog Weibo

    PubMed Central

    Wang, Fan; Zheng, Pinpin; Yang, Dongyun; Freeman, Becky; Fu, Hua; Chapman, Simon

    2014-01-01

    Background Although China ratified the WHO Framework Convention on Tobacco Control [FCTC] in 2005, the partial ban on tobacco advertising does not cover the internet. Weibo is one of the most important social media channels in China, using a format similar to its global counterpart, Twitter. The Weibo homepage is a platform to present products, brands and corporate culture. There is great potential for the tobacco industry to exploit Weibo to promote products. Methods Seven tobacco industry Weibo accounts that each had more than 5000 fans were selected to examine the content of Weibos established by tobacco companies or their advertising agents. Results Of the 12073 posts found on the seven accounts, 92.3% (11143) could be classified into six main themes: traditional culture, popular culture, social and business affairs, advertisement, public relations and tobacco culture. Posts under the theme of popular culture accounted for about half of total posts (49%), followed by ‘advertisement’ and ‘tobacco culture’ (both at 12%), ‘traditional culture’ and ‘public relations’ (both at 11%), and finally ‘social and business affairs’ (5%). 33% of posts included the words ‘cigarette’ or ‘smoking’ and 53% of posts included the tobacco brand name, indicating that tobacco companies carefully construct the topic and content of posts. Conclusions Weibo is an important new online marketing tool for the Chinese tobacco industry. Tobacco industry use of Weibo to promote brands and normalize smoking subverts China's ratification of the WHO FCTC. Policy to control tobacco promotion needs reforming to address this widespread circumvention of China's tobacco advertising ban. PMID:24914739

  19. Human Machine Learning Symbiosis

    ERIC Educational Resources Information Center

    Walsh, Kenneth R.; Hoque, Md Tamjidul; Williams, Kim H.

    2017-01-01

    Human Machine Learning Symbiosis is a cooperative system where both the human learner and the machine learner learn from each other to create an effective and efficient learning environment adapted to the needs of the human learner. Such a system can be used in online learning modules so that the modules adapt to each learner's learning state both…

  20. Symbiosis-mediated outbreaks

    USDA-ARS?s Scientific Manuscript database

    Symbiosis simply means "living together" and in its narrowest form can mean two species deriving mutual benefit from the association. Recent studies have made evident that insect associations with microorganisms can range the gamut from casual associations to obligate or context-dependent mutualisms...

  1. Survival through Symbiosis.

    ERIC Educational Resources Information Center

    Abdi, S. Wali

    1992-01-01

    Describes symbiosis and its significance in the day-to-day lives of plants and animals. Gives specific examples of mutualism, commensalism, and parasitism in the relationships among fungus and plant roots, animals and bacteria, birds and animals, fish, and predator and prey. (MDH)

  2. Survival through Symbiosis.

    ERIC Educational Resources Information Center

    Abdi, S. Wali

    1992-01-01

    Describes symbiosis and its significance in the day-to-day lives of plants and animals. Gives specific examples of mutualism, commensalism, and parasitism in the relationships among fungus and plant roots, animals and bacteria, birds and animals, fish, and predator and prey. (MDH)

  3. 76 FR 53816 - Softwood Lumber Research, Promotion, Consumer Education and Industry Information Order; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-30

    ... This rule establishes a Softwood Lumber Research, Promotion, Consumer Education and Industry... Agricultural Marketing Service 7 CFR Part 1217 RIN 0581-AD03 Softwood Lumber Research, Promotion, Consumer Education and Industry Information Order; Correction AGENCY: Agricultural Marketing Service. ACTION...

  4. Strategies for promoting renewables in a new electric industry

    SciTech Connect

    Driver, B.

    1996-12-31

    This paper describes strategies for promoting renewable resources in an era characterized by competitive pressures in the electric industry. It begins with a background section to describe the perspective from which I am writing and the nature of the pressures confronting renewables in 1996. Then, the paper turns to a discussion of the regulatory and other options to promote renewables in this environment. The major conclusion of the paper is that there is no {open_quotes}magic bullet{close_quotes} to guide the development of renewables through the developing competitive era within the electric industry. Indeed, it appears that the job can get done only through a combination of different measures at all levels of government. The author believes that among the most effective measures are likely to be: a national renewable resources generation standard; conditions attached to restructuring events; regional interstate compacts; regional risk-sharing consortia supported by federal and state tax and fiscal policy; and state {open_quotes}systems benefits charges;{close_quotes}

  5. Symbiosis-Promoting and Deleterious Effects of NopT, a Novel Type 3 Effector of Rhizobium sp. Strain NGR234▿

    PubMed Central

    Dai, Wei-Jun; Zeng, Yong; Xie, Zhi-Ping; Staehelin, Christian

    2008-01-01

    Establishment of symbiosis between certain host plants and nitrogen-fixing bacteria (“rhizobia”) depends on type 3 effector proteins secreted via the bacterial type 3 secretion system (T3SS). Here, we report that the open reading frame y4zC of strain NGR234 encodes a novel rhizobial type 3 effector, termed NopT (for nodulation outer protein T). Analysis of secreted proteins from NGR234 and T3SS mutants revealed that NopT is secreted via the T3SS. NopT possessed autoproteolytic activity when expressed in Escherichia coli or human HEK 293T cells. The processed NopT exposed a glycine (G50) to the N terminus, which is predicted to be myristoylated in eukaryotic cells. NopT with a point mutation at position C93, H205, or D220 (catalytic triad) showed strongly reduced autoproteolytic activity, indicating that NopT is a functional protease of the YopT-AvrPphB effector family. When transiently expressed in tobacco plants, proteolytically active NopT elicited a rapid hypersensitive reaction. Arabidopsis plants transformed with nopT showed chlorotic and necrotic symptoms, indicating a cytotoxic effect. Inoculation experiments with mutant derivatives of NGR234 indicated that NopT affected nodulation either positively (Phaseolus vulgaris cv. Yudou No. 1; Tephrosia vogelii) or negatively (Crotalaria juncea). We suggest that NopT-related polymorphism may be involved in evolutionary adaptation of NGR234 to particular host legumes. PMID:18487326

  6. Symbiosis-promoting and deleterious effects of NopT, a novel type 3 effector of Rhizobium sp. strain NGR234.

    PubMed

    Dai, Wei-Jun; Zeng, Yong; Xie, Zhi-Ping; Staehelin, Christian

    2008-07-01

    Establishment of symbiosis between certain host plants and nitrogen-fixing bacteria ("rhizobia") depends on type 3 effector proteins secreted via the bacterial type 3 secretion system (T3SS). Here, we report that the open reading frame y4zC of strain NGR234 encodes a novel rhizobial type 3 effector, termed NopT (for nodulation outer protein T). Analysis of secreted proteins from NGR234 and T3SS mutants revealed that NopT is secreted via the T3SS. NopT possessed autoproteolytic activity when expressed in Escherichia coli or human HEK 293T cells. The processed NopT exposed a glycine (G50) to the N terminus, which is predicted to be myristoylated in eukaryotic cells. NopT with a point mutation at position C93, H205, or D220 (catalytic triad) showed strongly reduced autoproteolytic activity, indicating that NopT is a functional protease of the YopT-AvrPphB effector family. When transiently expressed in tobacco plants, proteolytically active NopT elicited a rapid hypersensitive reaction. Arabidopsis plants transformed with nopT showed chlorotic and necrotic symptoms, indicating a cytotoxic effect. Inoculation experiments with mutant derivatives of NGR234 indicated that NopT affected nodulation either positively (Phaseolus vulgaris cv. Yudou No. 1; Tephrosia vogelii) or negatively (Crotalaria juncea). We suggest that NopT-related polymorphism may be involved in evolutionary adaptation of NGR234 to particular host legumes.

  7. 76 FR 55947 - Industrial Relations Promotion Project, Phase II in Vietnam

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-09

    ... of the Secretary Industrial Relations Promotion Project, Phase II in Vietnam AGENCY: Bureau of... funded.. DAI, through its Industrial Relations Promotion Project (IRRP), is the only organization that... disputes and sound industrial relations by developing approaches in cooperation with trade unions/worker...

  8. 7 CFR 1260.169 - Promotion, research, consumer information and industry information.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Promotion, research, consumer information and... Operating Committee § 1260.169 Promotion, research, consumer information and industry information. The... approval any plans and projects for promotion, research, consumer information and industry information...

  9. 7 CFR 1260.169 - Promotion, research, consumer information and industry information.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Promotion, research, consumer information and... Operating Committee § 1260.169 Promotion, research, consumer information and industry information. The... approval any plans and projects for promotion, research, consumer information and industry information...

  10. 78 FR 58956 - Softwood Lumber Research, Promotion, Consumer Education and Industry Information Order; Changes...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-25

    ... Research, Promotion, Consumer Education and Industry Information Order (Order). The Board administers the...--SOFTWOOD LUMBER RESEARCH, PROMOTION, CONSUMER EDUCATION AND INDUSTRY INFORMATION ORDER 0 1. The authority...; ] DEPARTMENT OF AGRICULTURE Agricultural Marketing Service 7 CFR Part 1217 Softwood Lumber Research, Promotion...

  11. Symbiosis in eukaryotic evolution.

    PubMed

    López-García, Purificación; Eme, Laura; Moreira, David

    2017-02-28

    Fifty years ago, Lynn Margulis, inspiring in early twentieth-century ideas that put forward a symbiotic origin for some eukaryotic organelles, proposed a unified theory for the origin of the eukaryotic cell based on symbiosis as evolutionary mechanism. Margulis was profoundly aware of the importance of symbiosis in the natural microbial world and anticipated the evolutionary significance that integrated cooperative interactions might have as mechanism to increase cellular complexity. Today, we have started fully appreciating the vast extent of microbial diversity and the importance of syntrophic metabolic cooperation in natural ecosystems, especially in sediments and microbial mats. Also, not only the symbiogenetic origin of mitochondria and chloroplasts has been clearly demonstrated, but improvement in phylogenomic methods combined with recent discoveries of archaeal lineages more closely related to eukaryotes further support the symbiogenetic origin of the eukaryotic cell. Margulis left us in legacy the idea of 'eukaryogenesis by symbiogenesis'. Although this has been largely verified, when, where, and specifically how eukaryotic cells evolved are yet unclear. Here, we shortly review current knowledge about symbiotic interactions in the microbial world and their evolutionary impact, the status of eukaryogenetic models and the current challenges and perspectives ahead to reconstruct the evolutionary path to eukaryotes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Speciation by Symbiosis: the Microbiome and Behavior.

    PubMed

    Shropshire, J Dylan; Bordenstein, Seth R

    2016-03-31

    Species are fundamental units of comparison in biology. The newly discovered importance and ubiquity of host-associated microorganisms are now stimulating work on the roles that microbes can play in animal speciation. We previously synthesized the literature and advanced concepts of speciation by symbiosis with notable attention to hybrid sterility and lethality. Here, we review recent studies and relevant data on microbes as players in host behavior and behavioral isolation, emphasizing the patterns seen in these analyses and highlighting areas worthy of additional exploration. We conclude that the role of microbial symbionts in behavior and speciation is gaining exciting traction and that the holobiont and hologenome concepts afford an evolving intellectual framework to promote research and intellectual exchange between disciplines such as behavior, microbiology, genetics, symbiosis, and speciation. Given the increasing centrality of microbiology in macroscopic life, microbial symbiosis is arguably the most neglected aspect of animal and plant speciation, and studying it should yield a better understanding of the origin of species.

  13. Speciation by Symbiosis: the Microbiome and Behavior

    PubMed Central

    Shropshire, J. Dylan

    2016-01-01

    ABSTRACT Species are fundamental units of comparison in biology. The newly discovered importance and ubiquity of host-associated microorganisms are now stimulating work on the roles that microbes can play in animal speciation. We previously synthesized the literature and advanced concepts of speciation by symbiosis with notable attention to hybrid sterility and lethality. Here, we review recent studies and relevant data on microbes as players in host behavior and behavioral isolation, emphasizing the patterns seen in these analyses and highlighting areas worthy of additional exploration. We conclude that the role of microbial symbionts in behavior and speciation is gaining exciting traction and that the holobiont and hologenome concepts afford an evolving intellectual framework to promote research and intellectual exchange between disciplines such as behavior, microbiology, genetics, symbiosis, and speciation. Given the increasing centrality of microbiology in macroscopic life, microbial symbiosis is arguably the most neglected aspect of animal and plant speciation, and studying it should yield a better understanding of the origin of species. PMID:27034284

  14. Tobacco industry use of flavourings to promote smokeless tobacco products.

    PubMed

    Kostygina, Ganna; Ling, Pamela M

    2016-11-01

    While fruit, candy and alcohol characterising flavours are not allowed in cigarettes in the USA, other flavoured tobacco products such as smokeless tobacco (ST) continue to be sold. We investigated tobacco manufacturers' use of flavoured additives in ST products, the target audience(s) for flavoured products, and marketing strategies promoting products by emphasising their flavour. Qualitative analysis of internal tobacco industry documents triangulated with data from national newspaper articles, trade press and internet. Internally, flavoured products have been consistently associated with young and inexperienced tobacco users. Internal studies confirmed that candy-like sweeter milder flavours (eg, mint, fruit) could increase appeal to starters by evoking a perception of mildness, blinding the strong tobacco taste and unpleasant mouth feel; or by modifying nicotine delivery by affecting product pH. Similar to cigarettes, flavoured ST is likely to encourage novices to start using tobacco, and regulations limiting or eliminating flavours in cigarettes should be extended to include flavoured ST products. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  15. 7 CFR 1220.230 - Promotion, research, consumer information, and industry information.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Promotion, research, consumer information, and...), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order Expenses and Assessments § 1220.230 Promotion, research, consumer information, and industry...

  16. 7 CFR 1220.230 - Promotion, research, consumer information, and industry information.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Promotion, research, consumer information, and...), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order Expenses and Assessments § 1220.230 Promotion, research, consumer information, and industry...

  17. Expanding genomics of mycorrhizal symbiosis

    SciTech Connect

    Kuo, Alan; Kohler, Annegret; Martin, Francis M.; Grigoriev, Igor V.

    2014-11-04

    The mycorrhizal symbiosis between soil fungi and plant roots is a ubiquitous mutualism that plays key roles in plant nutrition, soil health, and carbon cycling. The symbiosis evolved repeatedly and independently as multiple morphotypes [e.g., arbuscular mycorrhizae (AM), ectomycorrhizal (ECM)] in multiple fungal clades (e.g., phyla Glomeromycota, Ascomycota, Basidiomycota). The accessibility and cultivability of many mycorrhizal partners make them ideal models for symbiosis studies. Alongside molecular, physiological, and ecological investigations, sequencing led to the first three mycorrhizal fungal genomes, representing two morphotypes and three phyla. The genome of the ECM basidiomycete Laccaria bicolor showed that the mycorrhizal lifestyle can evolve through loss of plant cell wall-degrading enzymes (PCWDEs) and expansion of lineage-specific gene families such as short secreted protein (SSP) effectors. The genome of the ECM ascomycete Tuber melanosporum showed that the ECM type can evolve without expansion of families as in Laccaria, and thus a different set of symbiosis genes. The genome of the AM glomeromycete Rhizophagus irregularis showed that despite enormous phylogenetic distance and morphological difference from the other two fungi, symbiosis can involve similar solutions as symbiosis-induced SSPs and loss of PCWDEs. The three genomes provide a solid base for addressing fundamental questions about the nature and role of a vital mutualism.

  18. Expanding genomics of mycorrhizal symbiosis

    DOE PAGES

    Kuo, Alan; Kohler, Annegret; Martin, Francis M.; ...

    2014-11-04

    The mycorrhizal symbiosis between soil fungi and plant roots is a ubiquitous mutualism that plays key roles in plant nutrition, soil health, and carbon cycling. The symbiosis evolved repeatedly and independently as multiple morphotypes [e.g., arbuscular mycorrhizae (AM), ectomycorrhizal (ECM)] in multiple fungal clades (e.g., phyla Glomeromycota, Ascomycota, Basidiomycota). The accessibility and cultivability of many mycorrhizal partners make them ideal models for symbiosis studies. Alongside molecular, physiological, and ecological investigations, sequencing led to the first three mycorrhizal fungal genomes, representing two morphotypes and three phyla. The genome of the ECM basidiomycete Laccaria bicolor showed that the mycorrhizal lifestyle can evolvemore » through loss of plant cell wall-degrading enzymes (PCWDEs) and expansion of lineage-specific gene families such as short secreted protein (SSP) effectors. The genome of the ECM ascomycete Tuber melanosporum showed that the ECM type can evolve without expansion of families as in Laccaria, and thus a different set of symbiosis genes. The genome of the AM glomeromycete Rhizophagus irregularis showed that despite enormous phylogenetic distance and morphological difference from the other two fungi, symbiosis can involve similar solutions as symbiosis-induced SSPs and loss of PCWDEs. The three genomes provide a solid base for addressing fundamental questions about the nature and role of a vital mutualism.« less

  19. Expanding genomics of mycorrhizal symbiosis

    PubMed Central

    Kuo, Alan; Kohler, Annegret; Martin, Francis M.; Grigoriev, Igor V.

    2014-01-01

    The mycorrhizal symbiosis between soil fungi and plant roots is a ubiquitous mutualism that plays key roles in plant nutrition, soil health, and carbon cycling. The symbiosis evolved repeatedly and independently as multiple morphotypes [e.g., arbuscular mycorrhizae (AM), ectomycorrhizal (ECM)] in multiple fungal clades (e.g., phyla Glomeromycota, Ascomycota, Basidiomycota). The accessibility and cultivability of many mycorrhizal partners make them ideal models for symbiosis studies. Alongside molecular, physiological, and ecological investigations, sequencing led to the first three mycorrhizal fungal genomes, representing two morphotypes and three phyla. The genome of the ECM basidiomycete Laccaria bicolor showed that the mycorrhizal lifestyle can evolve through loss of plant cell wall-degrading enzymes (PCWDEs) and expansion of lineage-specific gene families such as short secreted protein (SSP) effectors. The genome of the ECM ascomycete Tuber melanosporum showed that the ECM type can evolve without expansion of families as in Laccaria, and thus a different set of symbiosis genes. The genome of the AM glomeromycete Rhizophagus irregularis showed that despite enormous phylogenetic distance and morphological difference from the other two fungi, symbiosis can involve similar solutions as symbiosis-induced SSPs and loss of PCWDEs. The three genomes provide a solid base for addressing fundamental questions about the nature and role of a vital mutualism. PMID:25408690

  20. Industry Self-Regulation as a Means to Promote Nonproliferation

    SciTech Connect

    Hund, Gretchen; Elkhamri, Oksana O.

    2005-10-01

    Companies within numerous industries that have been “early adopters” of self-regulation concept, considering the environment and society alongside business issues, have realized several benefits and some competitive advantage while substantially improving their environmental performance. Given that proliferation prevention is also a public good, our premise is that the experience gained and lessons learned from the self-regulation initiative in other industries and more broadly in the arena of sustainable development provide a basis for examining the feasibility of developing self-regulation mechanisms applicable to industries involved with sensitive technologies (nuclear, radiological source, and other dual-use industries)

  1. Arbuscular mycorrhizal symbiosis decreases strigolactone production in tomato.

    PubMed

    López-Ráez, Juan A; Charnikhova, Tatsiana; Fernández, Ivan; Bouwmeester, Harro; Pozo, Maria J

    2011-02-15

    Strigolactones are a new class of plant hormones emerging as important signals in the control of plant architecture. In addition, they are key elements in plant communication with several rhizosphere organisms. Strigolactones are exuded into the soil, where they act as host detection signals for arbuscular mycorrhizal (AM) fungi, but also as germination stimulants for root parasitic plant seeds. Under phosphate limiting conditions, plants up-regulate the secretion of strigolactones into the rhizosphere to promote the formation of AM symbiosis. Using tomato as a model plant, we have recently shown that AM symbiosis induces changes in transcriptional and hormonal profiles. Using the same model system, here we analytically demonstrate, using liquid chromatography-tandem mass spectrometry, that strigolactone production is also significantly reduced upon AM symbiosis. Considering the dual role of the strigolactones in the rhizosphere as signals for AM fungi and parasitic plants, we discuss the potential implications of these changes in the plant interaction with both organisms.

  2. The application of powerful promoters to enhance gene expression in industrial microorganisms.

    PubMed

    Zhou, Shenghu; Du, Guocheng; Kang, Zhen; Li, Jianghua; Chen, Jian; Li, Huazhong; Zhou, Jingwen

    2017-02-01

    Production of useful chemicals by industrial microorganisms has been attracting more and more attention. Microorganisms screened from their natural environment usually suffer from low productivity, low stress resistance, and accumulation of by-products. In order to overcome these disadvantages, rational engineering of microorganisms to achieve specific industrial goals has become routine. Rapid development of metabolic engineering and synthetic biology strategies provide novel methods to improve the performance of industrial microorganisms. Rational regulation of gene expression by specific promoters is essential to engineer industrial microorganisms for high-efficiency production of target chemicals. Identification, modification, and application of suitable promoters could provide powerful switches at the transcriptional level for fine-tuning of a single gene or a group of genes, which are essential for the reconstruction of pathways. In this review, the characteristics of promoters from eukaryotic, prokaryotic, and archaea microorganisms are briefly introduced. Identification of promoters based on both traditional biochemical and systems biology routes are summarized. Besides rational modification, de novo design of promoters to achieve gradient, dynamic, and logic gate regulation are also introduced. Furthermore, flexible application of static and dynamic promoters for the rational engineering of industrial microorganisms is highlighted. From the perspective of powerful promoters in industrial microorganisms, this review will provide an extensive description of how to regulate gene expression in industrial microorganisms to achieve more useful goals.

  3. Symbiosis, Empathy, Suicidal Behavior, and the Family.

    ERIC Educational Resources Information Center

    Richman, Joseph

    1978-01-01

    This paper discusses the theoretical concept of symbiosis, as described by Mahler and her co-workers, and its clinical applications in suicidal situations. Also, the practical implications of the concept of symbiosis for assessment and treatment are discussed (Author)

  4. Symbiosis in Paramecium Bursaria.

    PubMed

    Karakashian, M W

    1975-01-01

    Paramecium bursaria normally appears green dut to several hundred symbiotic Chlorella which are dispersed throughout its cytoplasm. The symbionts are situated within individual vacuoles and these alga-vacuole complexes grow and divide at a rate compatible with that of the paramecium. The symbiotic units also persist through conjugation and the subsequent reorganization of the host. Studies of the benefit of the symbiosis to the ciliate hosts have shown that they are able to grow and survive better than aposymbiotic animals in environments deficient in bacteria. The symbionts are also able to extract nourishment from the host when it is well fed and they are deprived of light. The biochemical nature of these exchanges has not been determined. Potential symbionts usually enter the host in food vacuoles. If they are ingested in sufficient numbers, they are able to interfere with the normal course of host digestion, perhaps by preventing the release of digestive enzymes into the food vacuole. All natural symbionts of P. bursaria appear able to reinfect aposymbiotic cells. Some freeliving strains of Chlorella and related algae are also infective, but these associations are relatively unstable and provide little evident benefit to the host. Host susceptibility to infection by certain strains of free-living algae is invariably lost with time. This loss is specific and often rapid, but it does not occur simultaneously in subcultures derived from the original susceptible culture. The basis for these susceptibility changes is still unknown, but they may be related to long-lasting effect of the previous symbionts on the digestive efficiency of the paramecium host.

  5. Mycorrhizal symbiosis in leeks increases plant growth under low phosphorus and affects the levels of specific flavonoid glycosides

    USDA-ARS?s Scientific Manuscript database

    Introduction- Mycorrhizae symbiosis is a universal phenomenon in nature that promotes plant growth and food quality in most plants, especially, under phosphorus deficiency and water stress. Objective- The objective of this study was to assess the effects of mycorrhizal symbiosis on changes in the le...

  6. A review of environmental and economic regulations for promoting industrial waste recycling in Taiwan.

    PubMed

    Tsai, W T; Chou, Y H

    2004-01-01

    The objective of this paper is to present a compilation of recent Taiwan government laws/regulations to promote industrial waste recycling. The description is thus centered on legislation/regulations concerning general industrial wastes recycling in the policies of environmental protection, economic incentives and engineering technologies (3E) that have become effective since 2001. The regulatory system, including Waste Disposal Act, Resource Recycling/Reuse Act, Environmental Basis Law, and Statute for Upgrading Industries, not only gives financial incentives, but also provides technical assistance and information transfer on promoting industrial waste recycling. In order to further utilize the recyclable resources and upgrade the environmental technology, Taiwan's Environmental Protection Administration (EPA), in cooperation with the Ministry of Economic Affairs (MOEA), has jointly ventured some promotion programs, which highlight an Industrial Waste Exchange Information Center and Environmental Technology Park Development Program, also described in the paper.

  7. The Role of Universities in the Entrepreneurship Industry: Promoting the Entrepreneurship Agenda in HEIs

    ERIC Educational Resources Information Center

    McGowan, Pauric; van der Sijde, Peter; Kirby, David

    2008-01-01

    It is becoming increasing clear that a new industry--the entrepreneurship industry--is in the ascendant and that universities are a part of this development. Furthermore, the idea of the entrepreneurial university has only recently entered the debate. Promoting the entrepreneurship agenda within constituencies where it is not traditionally…

  8. The Microbiota, Chemical Symbiosis, and Human Disease

    PubMed Central

    Redinbo, Matthew R.

    2014-01-01

    Our understanding of mammalian-microbial mutualism has expanded by combing microbial sequencing with evolving molecular and cellular methods, and unique model systems. Here, the recent literature linking the microbiota to diseases of three of the key mammalian mucosal epithelial compartments – nasal, lung and gastrointestinal (GI) tract – is reviewed with a focus on new knowledge about the taxa, species, proteins and chemistry that promote health and impact progression toward disease. The information presented is further organized by specific diseases now associated with the microbiota:, Staphylococcus aureus infection and rhinosinusitis in the nasal-sinus mucosa; cystic fibrosis (CF), chronic obstructive pulmonary disorder (COPD), and asthma in the pulmonary tissues. For the vast and microbially dynamic GI compartment, several disorders are considered, including obesity, atherosclerosis, Crohn’s disease, ulcerative colitis, drug toxicity, and even autism. Our appreciation of the chemical symbiosis ongoing between human systems and the microbiota continues to grow, and suggest new opportunities for modulating this symbiosis using designed interventions. PMID:25305474

  9. 7 CFR 1220.230 - Promotion, research, consumer information, and industry information.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and..., research, consumer information, and industry information activities with respect to soybean and soybean..., marketing and utilization of soybean and soybean products and the creation of new products thereof, to...

  10. 7 CFR 1220.230 - Promotion, research, consumer information, and industry information.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and..., research, consumer information, and industry information activities with respect to soybean and soybean..., marketing and utilization of soybean and soybean products and the creation of new products thereof, to...

  11. 78 FR 77329 - Softwood Lumber Research, Promotion, Consumer Education and Industry Information Order; Changes...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-23

    ... Agricultural Marketing Service 7 CFR Part 1217 Softwood Lumber Research, Promotion, Consumer Education and... Board (Board) established under the Softwood Lumber Research, Promotion, Consumer Education and Industry..., Research, and Information Act of 1996 (1996 Act) (7 U.S.C. 7411-7425). Executive Orders 12866 and 13563...

  12. [Establishment of industry promotion technology system in Chinese medicine secondary exploitation based on "component structure theory"].

    PubMed

    Cheng, Xu-Dong; Feng, Liang; Zhang, Ming-Hua; Gu, Jun-Fei; Jia, Xiao-Bin

    2014-10-01

    The purpose of the secondary exploitation of Chinese medicine is to improve the quality of Chinese medicine products, enhance core competitiveness, for better use in clinical practice, and more effectively solve the patient suffering. Herbs, extraction, separation, refreshing, preparation and quality control are all involved in the industry promotion of Chinese medicine secondary exploitation of industrial production. The Chinese medicine quality improvement and industry promotion could be realized with the whole process of process optimization, quality control, overall processes improvement. Based on the "component structure theory", "multi-dimensional structure & process dynamic quality control system" and systematic and holistic character of Chinese medicine, impacts of whole process were discussed. Technology systems of Chinese medicine industry promotion was built to provide theoretical basis for improving the quality and efficacy of the secondary development of traditional Chinese medicine products.

  13. Double promoter expression systems for recombinant protein production by industrial microorganisms.

    PubMed

    Öztürk, Sibel; Ergün, Burcu Gündüz; Çalık, Pınar

    2017-09-12

    Using double promoter expression systems is a promising approach to increase heterologous protein production. In this review, current double promoter expression systems for the production of recombinant proteins (r-proteins) by industrially important bacteria, Bacillus subtilis and Escherichia coli; and yeasts, Saccharomyces cerevisiae and Pichia pastoris, are discussed by assessing their potentials and drawbacks. Double promoter expression systems need to be designed to maintain a higher specific product formation rate within the production domain. While bacterial double promoter systems have been constructed as chimeric tandem promoters, yeast dual promoter systems have been developed as separate expression cassettes. To increase production and productivity, the optimal transcriptional activity should be justified either by simultaneously satisfying the requirements of both promoters, or by consecutively stimulating the changeover from one to another in a biphasic process or via successive-iterations. Thus, considering the dynamics of a fermentation process, double promoters can be classified according to their operational mechanisms, as: i) consecutively operating double promoter systems, and ii) simultaneously operating double promoter systems. Among these metabolic design strategies, extending the expression period with two promoters activated under different conditions, or enhancing the transcriptional activity with two promoters activated under similar conditions within the production domain, can be applied independently from the host. Novel studies with new insights, which aim a rational systematic design and construction of dual promoter expression vectors with tailored transcriptional activity, will empower r-protein production with enhanced production and productivity. Finally, the current state-of-the-art review emphasizes the advantages of double promoter systems along with the necessity for discovering new promoters for the development of more

  14. How did the Master Settlement Agreement change tobacco industry expenditures for cigarette advertising and promotions?

    PubMed

    Pierce, John P; Gilpin, Elizabeth A

    2004-07-01

    The 1998 multistate Master Settlement Agreement (MSA) with the tobacco industry restricted cigarette advertising and promotions. The MSA monetary settlement was also associated with an average cigarette price increase of U.S.$1.19/pack between 1998 and 2001 to fund, in part, industry payments to the states. We examined Federal Trade Commission reports on how the tobacco industry spends its cigarette advertising and promotional dollars to see if changes expected as a result of the MSA occurred. Expected changes included reduced total expenditures and reductions for outdoor advertising, specialty promotional items identified with a brand (e.g., caps, t-shirts, lighters), and public entertainment. However, tobacco industry spending for advertising and promotions increased 96% between 1995 and 2001, with large increases in 1998 and 1999, as the MSA took effect. Between 1997 and 2001, outdoor advertising declined 98%, expenditures for specialty promotional items decreased 41%, although public entertainment increased 45%. However, in 2001, these categories represented only a small fraction of the total budget. Expenditures for retail-value-added increased 344% between 1997 and 2001 (to 42.5% of total), perhaps to mitigate increased cigarette prices. In 2001, the incentives-to-merchants and retail-value-added categories comprised more than 80% of total expenditures. To adequately monitor tobacco industry expenditures as they adapt to the MSA and other tobacco control efforts, more refined reporting categories are essential.

  15. Is Industry-University Interaction Promoting Innovation in the Brazilian Pharmaceutical Industry?

    ERIC Educational Resources Information Center

    Paranhos, Julia; Hasenclever, Lia

    2011-01-01

    This paper analyses industry-university interaction and its characteristics in the Brazilian pharmaceutical system of innovation, taking account of the relevance of company strategies, the approach of the universities and the actions of government. By analysing primary and secondary data the authors show that, for as long as corporate investment…

  16. Is Industry-University Interaction Promoting Innovation in the Brazilian Pharmaceutical Industry?

    ERIC Educational Resources Information Center

    Paranhos, Julia; Hasenclever, Lia

    2011-01-01

    This paper analyses industry-university interaction and its characteristics in the Brazilian pharmaceutical system of innovation, taking account of the relevance of company strategies, the approach of the universities and the actions of government. By analysing primary and secondary data the authors show that, for as long as corporate investment…

  17. Phosphorus and Nitrogen Regulate Arbuscular Mycorrhizal Symbiosis in Petunia hybrida

    PubMed Central

    Nouri, Eva; Breuillin-Sessoms, Florence; Feller, Urs; Reinhardt, Didier

    2014-01-01

    Phosphorus and nitrogen are essential nutrient elements that are needed by plants in large amounts. The arbuscular mycorrhizal symbiosis between plants and soil fungi improves phosphorus and nitrogen acquisition under limiting conditions. On the other hand, these nutrients influence root colonization by mycorrhizal fungi and symbiotic functioning. This represents a feedback mechanism that allows plants to control the fungal symbiont depending on nutrient requirements and supply. Elevated phosphorus supply has previously been shown to exert strong inhibition of arbuscular mycorrhizal development. Here, we address to what extent inhibition by phosphorus is influenced by other nutritional pathways in the interaction between Petunia hybrida and R. irregularis. We show that phosphorus and nitrogen are the major nutritional determinants of the interaction. Interestingly, the symbiosis-promoting effect of nitrogen starvation dominantly overruled the suppressive effect of high phosphorus nutrition onto arbuscular mycorrhiza, suggesting that plants promote the symbiosis as long as they are limited by one of the two major nutrients. Our results also show that in a given pair of symbiotic partners (Petunia hybrida and R. irregularis), the entire range from mutually symbiotic to parasitic can be observed depending on the nutritional conditions. Taken together, these results reveal complex nutritional feedback mechanisms in the control of root colonization by arbuscular mycorrhizal fungi. PMID:24608923

  18. Phosphorus and nitrogen regulate arbuscular mycorrhizal symbiosis in Petunia hybrida.

    PubMed

    Nouri, Eva; Breuillin-Sessoms, Florence; Feller, Urs; Reinhardt, Didier

    2014-01-01

    Phosphorus and nitrogen are essential nutrient elements that are needed by plants in large amounts. The arbuscular mycorrhizal symbiosis between plants and soil fungi improves phosphorus and nitrogen acquisition under limiting conditions. On the other hand, these nutrients influence root colonization by mycorrhizal fungi and symbiotic functioning. This represents a feedback mechanism that allows plants to control the fungal symbiont depending on nutrient requirements and supply. Elevated phosphorus supply has previously been shown to exert strong inhibition of arbuscular mycorrhizal development. Here, we address to what extent inhibition by phosphorus is influenced by other nutritional pathways in the interaction between Petunia hybrida and R. irregularis. We show that phosphorus and nitrogen are the major nutritional determinants of the interaction. Interestingly, the symbiosis-promoting effect of nitrogen starvation dominantly overruled the suppressive effect of high phosphorus nutrition onto arbuscular mycorrhiza, suggesting that plants promote the symbiosis as long as they are limited by one of the two major nutrients. Our results also show that in a given pair of symbiotic partners (Petunia hybrida and R. irregularis), the entire range from mutually symbiotic to parasitic can be observed depending on the nutritional conditions. Taken together, these results reveal complex nutritional feedback mechanisms in the control of root colonization by arbuscular mycorrhizal fungi.

  19. 78 FR 24152 - Softwood Lumber Research, Promotion, Consumer Education and Industry Information Order; Request...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-24

    ... Agricultural Marketing Service Softwood Lumber Research, Promotion, Consumer Education and Industry Information...: Agricultural Marketing Service, USDA. ACTION: Notice and request for comments. SUMMARY: In accordance with the Paperwork Reduction Act of 1995 (44 U.S.C. Chapter 35), this document announces the Agricultural...

  20. Molecular marker genes for ectomycorrhizal symbiosis

    Treesearch

    Shiv Hiremath; Carolyn McQuattie; Gopi Podila; Jenise. Bauman

    2013-01-01

    Mycorrhizal symbiosis is a mutually beneficial association very commonly found among most vascular plants. Formation of mycorrhiza happens only between compatible partners and predicting this is often accomplished through a trial and error process. We investigated the possibility of using expression of symbiosis specific genes as markers to predict the formation of...

  1. A novel reef coral symbiosis

    NASA Astrophysics Data System (ADS)

    Pantos, O.; Bythell, J. C.

    2010-09-01

    Reef building corals form close associations with unicellular microalgae, fungi, bacteria and archaea, some of which are symbiotic and which together form the coral holobiont. Associations with multicellular eukaryotes such as polychaete worms, bivalves and sponges are not generally considered to be symbiotic as the host responds to their presence by forming physical barriers with an active growth edge in the exoskeleton isolating the invader and, at a subcellular level, activating innate immune responses such as melanin deposition. This study describes a novel symbiosis between a newly described hydrozoan ( Zanclea margaritae sp. nov.) and the reef building coral Acropora muricata (= A. formosa), with the hydrozoan hydrorhiza ramifying throughout the coral tissues with no evidence of isolation or activation of the immune systems of the host. The hydrorhiza lacks a perisarc, which is typical of symbiotic species of this and related genera, including species that associate with other cnidarians such as octocorals. The symbiosis was observed at all sites investigated from two distant locations on the Great Barrier Reef, Australia, and appears to be host species specific, being found only in A. muricata and in none of 30 other species investigated at these sites. Not all colonies of A. muricata host the hydrozoans and both the prevalence within the coral population (mean = 66%) and density of emergent hydrozoan hydranths on the surface of the coral (mean = 4.3 cm-2, but up to 52 cm-2) vary between sites. The form of the symbiosis in terms of the mutualism-parasitism continuum is not known, although the hydrozoan possesses large stenotele nematocysts, which may be important for defence from predators and protozoan pathogens. This finding expands the known A. muricata holobiont and the association must be taken into account in future when determining the corals’ abilities to defend against predators and withstand stress.

  2. Perspectives on Workplace Health Promotion Among Employees in Low-Wage Industries.

    PubMed

    Hammerback, Kristen; Hannon, Peggy A; Harris, Jeffrey R; Clegg-Thorp, Catherine; Kohn, Marlana; Parrish, Amanda

    2015-01-01

    Study goals were to (1) understand the attitudes of employees in low-wage industries toward workplace health promotion, including views on appropriateness of employer involvement in employee health and level of interest in workplace health promotion overall and in specific programs, and (2) determine the potential for extending workplace health promotion to spouses and partners of these employees. The study used 42 interviews of 60 to 90 minutes. Interviews were conducted with couples (married or living together) in the Seattle/King County metropolitan area of Washington State. Study participants were forty-two couples with one or more members working in one of five low-wage industries: accommodation/food services, education, health care/social assistance, manufacturing, and retail trade. The study employed qualitative analysis of interview transcripts using grounded theory to identify themes. Employees consider workplace health promotion both appropriate and desirable and believe it benefits employers through increased productivity and morale. Most have little personal experience with it and doubt their employers would prioritize employee health. Employees are most interested in efforts focused on nutrition and physical activity. Both employees and their partners support extending workplace health promotion to include partners. Employees and their partners are interested in workplace health promotion if it addresses behaviors they care about. Concern over employer involvement in their personal health decisions is minimal; instead, employees view employer interest in their health as a sign that they are valued.

  3. Perspectives on workplace health promotion among employees in low-wage industries

    PubMed Central

    Hammerback, Kristen; Hannon, Peggy A.; Harris, Jeffrey R.; Clegg-Thorp, Catherine; Kohn, Marlana; Parrish, Amanda

    2016-01-01

    Purpose Study goals were to (a) understand the attitudes of employees in low-wage industries toward workplace health promotion, including views on appropriateness of employer involvement in employee health, and level of interest in workplace health promotion overall and in specific programs; and (b) determine the potential for extending workplace health promotion to spouses and partners of these employees. Approach Forty-two 60-90-minute interviews Setting Interviews were conducted with couples (married or living together) in the Seattle/King County metropolitan area of Washington State. Participants Forty-two couples with one or more members working in one of five low-wage industries: accommodation/food services, education, health care/social assistance, manufacturing, and retail trade. Method Qualitative analysis of interview transcripts using grounded theory to identify themes. Results Employees consider workplace health promotion both appropriate and desirable, and believe it benefits employers through increased productivity and morale. Most have little personal experience with it and doubt their employers would prioritize employee health. Employees are most interested in efforts focused on nutrition and physical activity. Both employees and their partners support extending workplace health promotion to include partners. Conclusion Employees and their partners are interested in workplace health promotion if it addresses behaviors they care about. Concern over employer involvement in their personal health decisions is minimal; instead, employees view employer interest in their health as a sign that they are valued. PMID:25162321

  4. Promoting physical activity and healthy eating: convergence in framing the role of industry.

    PubMed

    Dorfman, Lori; Yancey, Antronette K

    2009-10-01

    This commentary addresses a little explored aspect of prevention, namely, how public health practitioners conceptualize the roles of industries whose business interests may be at odds with physical activity and eating nutrient-rich foods. Taking their cues from successful campaigns in tobacco control, many public health advocates have framed obesity as a battle with the food industry. Such framing presents problems when it exacerbates existing tensions between practitioners in nutrition and physical activity, and alienates potential fitness industry partners. Creating healthy environments requires reframing expectations of all industries that influence physical activity and inactivity. A broader view of the influence of corporate practices on physical and social environments will help both physical activity and nutrition advocates identify what they can do together, and in partnership with the business sector, to create environments that promote activity and nutritious eating.

  5. [Are medical students influenced by the promotion of the pharmaceutical industry?].

    PubMed

    Giustetto, Guido

    2014-12-01

    The pharmaceutical and medical devices industry provides one of the main sources of scientific information for physicians. The impact of this kind of information on physicians' prescribing behavior has been extensively studied. Available evidence consistently shows that prescription habits are affected by industry-driven scientific research data. This questionable influence has an impact also on medical students, residents, and doctors in training. Recent studies have shown that a frequent contact with industry representatives is inversely related to the knowledge of the foundations of evidence-based medicine and directly related to a higher use of brand-name prescription drugs. Several American universities decided to prohibit any relationships between students and industry representatives. It would be desirable that such policies be adopted by other institutions. In addition, the practical guide published by the World Health Organization "Understanding and Responding to Pharmaceutical Promotion" should be better known and used.

  6. The role of tobacco advertising and promotion: themes employed in litigation by tobacco industry witnesses

    PubMed Central

    Goldberg, Marvin E; Davis, Ronald M; O'Keefe, Anne Marie

    2006-01-01

    Objectives To identify key themes related to tobacco advertising and promotion in testimony provided by tobacco industry‐affiliated witnesses in tobacco litigation, and to present countervailing evidence and arguments. Methods Themes in industry testimony were identified by review of transcripts of testimony in the Tobacco Deposition and Trial Testimony Archive (http://tobaccodocuments.org/datta) from a sample of defence witnesses, including three academic expert witnesses, six senior executives of tobacco companies, and one industry advertising consultant. Counterarguments to the themes embodied in defence testimony were based on information from peer‐reviewed literature, advertising trade publications, government reports, tobacco industry documents, and testimony provided by expert witnesses testifying for plaintiffs. Results Five major themes employed by defence witnesses were identified: (1) tobacco advertising has a relatively weak “share of voice” in the marketing environment and is a weak force in affecting smoking behaviour; (2) tobacco advertising and promotion do not create new smokers, expand markets, or increase total tobacco consumption; (3) the tobacco industry does not target, study, or track youth smoking; (4) tobacco advertising and promotion do not cause smoking initiation by youth; and (5) tobacco companies and the industry adhere closely to relevant laws, regulations, and industry voluntary codes. Substantial evidence exists in rebuttal to these arguments. Conclusions Tobacco industry‐affiliated witnesses have marshalled many arguments to deny the adverse effects of tobacco marketing activities and to portray tobacco companies as responsible corporate citizens. Effective rebuttals to these arguments exist, and plaintiffs' attorneys have, with varying degrees of success, presented them to judges and juries. PMID:17130625

  7. Ready or Not: Microbial Adaptive Responses in Dynamic Symbiosis Environments.

    PubMed

    Cao, Mengyi; Goodrich-Blair, Heidi

    2017-08-01

    In mutually beneficial and pathogenic symbiotic associations, microbes must adapt to the host environment for optimal fitness. Both within an individual host and during transmission between hosts, microbes are exposed to temporal and spatial variation in environmental conditions. The phenomenon of phenotypic variation, in which different subpopulations of cells express distinctive and potentially adaptive characteristics, can contribute to microbial adaptation to a lifestyle that includes rapidly changing environments. The environments experienced by a symbiotic microbe during its life history can be erratic or predictable, and each can impact the evolution of adaptive responses. In particular, the predictability of a rhythmic or cyclical series of environments may promote the evolution of signal transduction cascades that allow preadaptive responses to environments that are likely to be encountered in the future, a phenomenon known as adaptive prediction. In this review, we summarize environmental variations known to occur in some well-studied models of symbiosis and how these may contribute to the evolution of microbial population heterogeneity and anticipatory behavior. We provide details about the symbiosis between Xenorhabdus bacteria and Steinernema nematodes as a model to investigate the concept of environmental adaptation and adaptive prediction in a microbial symbiosis. Copyright © 2017 American Society for Microbiology.

  8. Symbiosis.

    ERIC Educational Resources Information Center

    Bicevskis, Rob

    2002-01-01

    Exposing today's students to a balance of science and the outside world is critical. The outdoors provides a context for practical applications of science, exposing the relevance of science to everyday life. Outdoor education instills an awareness that the health of the environment is directly coupled with our own health, enabling us to make…

  9. Oral health promotion by the oral health products industry: unrecognised and unappreciated?

    PubMed

    Barnett, M L

    2008-03-01

    There is often ambivalence in the way dentists view the oral health care industry. On the one hand, there are the skeptics who view corporate activities as suspect, calling into question the validity of industry-sponsored research and considering all promotional activities as self-serving. On the other hand, there are those who will evaluate research, whether industry sponsored or not, on its merits and appreciate corporate philanthropy that aims to give something back to the profession, although at times the expectations of the amount of financial support available are markedly in excess of the actual amount based on dental product sales. (Yes--and don't let your young children see this!--the tooth fairy who goes around dispensing endless number of dollars or pounds or euros does not actually exist!) Recognizing that, of necessity, corporations exist to make a profit, I would submit that the relationship of responsible companies to the profession can often be looked at as a partnership in which both sides benefit. Ultimately, all have as a goal the improvement of the oral health of our patients (or consumers) which is facilitated by the availability of effective products. In addition to marketing products, the oral care industry plays a large, though oftentimes unnoticed, role in oral health promotion. For the most part, this involves targeted financial support or contributions of products that serve to enhance patients' understanding of oral diseases and the need for good oral care, and/or provide access to care for underserved groups. In the following sections, I will give some examples of industry-supported health promotion activities, most of which will be activities in the United States with which I am most familiar. These are examples only--the list is not intended to be exhaustive and a company's name will be included in only the few instances in which it is an integral part of the programme title.

  10. Metabolic symbiosis at the origin of eukaryotes.

    PubMed

    López-Garćia, P; Moreira, D

    1999-03-01

    Thirty years after Margulis revived the endosymbiosis theory for the origin of mitochondria and chloroplasts, two novel symbiosis hypotheses for the origin of eukaryotes have been put forward. Both propose that eukaryotes arose through metabolic symbiosis (syntrophy) between eubacteria and methanogenic Archaea. They also propose that this was mediated by interspecies hydrogen transfer and that, initially, mitochondria were anaerobic. These hypotheses explain the mosaic character of eukaryotes (i.e. an archaeal-like genetic machinery and a eubacterial-like metabolism), as well as distinct eukaryotic characteristics (which are proposed to be products of symbiosis). Combined data from comparative genomics, microbial ecology and the fossil record should help to test their validity.

  11. Differential spatio-temporal expression of carotenoid cleavage dioxygenases regulates apocarotenoid fluxes during AM symbiosis.

    PubMed

    López-Ráez, Juan A; Fernández, Iván; García, Juan M; Berrio, Estefanía; Bonfante, Paola; Walter, Michael H; Pozo, María J

    2015-01-01

    Apocarotenoids are a class of compounds that play important roles in nature. In recent years, a prominent role for these compounds in arbuscular mycorrhizal (AM) symbiosis has been shown. They are derived from carotenoids by the action of the carotenoid cleavage dioxygenase (CCD) enzyme family. In the present study, using tomato as a model, the spatio-temporal expression pattern of the CCD genes during AM symbiosis establishment and functioning was investigated. In addition, the levels of the apocarotenoids strigolactones (SLs), C13 α-ionol and C14 mycorradicin (C13/C14) derivatives were analyzed. The results suggest an increase in SLs promoted by the presence of the AM fungus at the early stages of the interaction, which correlated with an induction of the SL biosynthesis gene SlCCD7. At later stages, induction of SlCCD7 and SlCCD1 expression in arbusculated cells promoted the production of C13/C14 apocarotenoid derivatives. We show here that the biosynthesis of apocarotenoids during AM symbiosis is finely regulated throughout the entire process at the gene expression level, and that CCD7 constitutes a key player in this regulation. Once the symbiosis is established, apocarotenoid flux would be turned towards the production of C13/C14 derivatives, thus reducing SL biosynthesis and maintaining a functional symbiosis.

  12. Developing Entrepreneurial and Technology Commercialization Policies to Promote Cooperative Ventures Between NIH and Industry

    NASA Astrophysics Data System (ADS)

    Rossomando, Edward F.

    2001-03-01

    The NIH has had a great influence in guiding the biological research agenda for the last half of the 20th century. This may change if the increases in research funding from the private sector that occurred in the last ten years continue into the 21st century. Ten years ago, industry supplied 55% of the US R&D funds. In 2000, industry support of R&D had increased to 76%, with industry carrying out 70% of the nations applied and 91% of its development research. Given this shift, one of the biggest challenges that NIH may face in coming years is sharing control of America's research agenda with industry. For this to occur policies that encourage cooperative ventures with industry are needed. In a unique experiment, I was invited to the National Institute of Dental and Craniofacial Research (NIDCR), one of the 25 NIH Institutes and Centers, to develop programs and policies that would promote interactions with industry. This talk will introduce the strategy and programs developed to commercialize products and technologies from basic science discoveries and introducing an entrepreneurial atmosphere within the Institute. The results of this experiment will be discussed by comparing differences between discovery-driven and customer-driven innovation. One outcome of this experience is a greater appreciation of the obstacles to introducing disruptive technologies into the market place and of the paradigms that serve as barriers to commercialization. One recommendation is that the NIDCR consider a policy that allows for some participation by industry in setting the research and training agenda of the Institute, and that a mechanism for industry input be introduced into its administrative organization.

  13. The Rhizobium-plant symbiosis.

    PubMed Central

    van Rhijn, P; Vanderleyden, J

    1995-01-01

    Rhizobium, Bradyrhizobium, and Azorhizobium species are able to elicit the formation of unique structures, called nodules, on the roots or stems of the leguminous host. In these nodules, the rhizobia convert atmospheric N2 into ammonia for the plant. To establish this symbiosis, signals are produced early in the interaction between plant and rhizobia and they elicit discrete responses by the two symbiotic partners. First, transcription of the bacterial nodulation (nod) genes is under control of the NodD regulatory protein, which is activated by specific plant signals, flavonoids, present in the root exudates. In return, the nod-encoded enzymes are involved in the synthesis and excretion of specific lipooligosaccharides, which are able to trigger on the host plant the organogenic program leading to the formation of nodules. An overview of the organization, regulation, and function of the nod genes and their participation in the determination of the host specificity is presented. PMID:7708010

  14. Transnational tobacco industry promotion of the cigarette gifting custom in China.

    PubMed

    Chu, Alexandria; Jiang, Nan; Glantz, Stanton A

    2011-07-01

    To understand how British American Tobacco (BAT) and Philip Morris (PM) researched the role and popularity of cigarette gifting in forming relationships among Chinese customs and how they exploited the practice to promote their brands State Express 555 and Marlboro. Searches and analysis of industry documents from the Legacy Tobacco Documents Library complemented by searches on LexisNexis Academic news, online search engines and information from the tobacco industry trade press. From 1980-1999, BAT and PM employed Chinese market research firms to gather consumer information about perceptions of foreign cigarettes and the companies discovered that cigarettes, especially prestigious ones, were gifted and smoked purposely for building relationships and social status in China. BAT and PM promoted their brands as gifts by enhancing cigarette cartons and promoting culturally themed packages, particularly during the gifting festivals of Chinese New Year and Mid-Autumn Festival to tie their brands in to festival values such as warmth, friendship and celebration. They used similar marketing in Chinese communities outside China. BAT and PM tied their brands to Chinese cigarette gifting customs by appealing to social and cultural values of respect and personal honour. Decoupling cigarettes from their social significance in China and removing their appeal would probably reduce cigarette gifting and promote a decline in smoking. Tobacco control efforts in countermarketing, large graphic warnings and plain packaging to make cigarette packages less attractive as gifts could contribute to denormalising cigarette gifting.

  15. Transnational tobacco industry promotion of the cigarette gifting custom in China

    PubMed Central

    Chu, Alexandria; Jiang, Nan; Glantz, Stanton A

    2011-01-01

    Objective To understand how British American Tobacco (BAT) and Philip Morris (PM) researched the role and popularity of cigarette gifting in forming relationships among Chinese customs and how they exploited the practice to promote their brands State Express 555 and Marlboro. Methods Searches and analysis of industry documents from the Legacy Tobacco Documents Library complemented by searches on LexisNexis Academic news, online search engines and information from the tobacco industry trade press. Results From 1980–1999, BAT and PM employed Chinese market research firms to gather consumer information about perceptions of foreign cigarettes and the companies discovered that cigarettes, especially prestigious ones, were gifted and smoked purposely for building relationships and social status in China. BAT and PM promoted their brands as gifts by enhancing cigarette cartons and promoting culturally themed packages, particularly during the gifting festivals of Chinese New Year and Mid-Autumn Festival to tie their brands in to festival values such as warmth, friendship and celebration. They used similar marketing in Chinese communities outside China. Conclusions BAT and PM tied their brands to Chinese cigarette gifting customs by appealing to social and cultural values of respect and personal honour. Decoupling cigarettes from their social significance in China and removing their appeal would probably reduce cigarette gifting and promote a decline in smoking. Tobacco control efforts in countermarketing, large graphic warnings and plain packaging to make cigarette packages less attractive as gifts could contribute to denormalising cigarette gifting. PMID:21282136

  16. Rhizobial symbiosis effect on the growth, metal uptake, and antioxidant responses of Medicago lupulina under copper stress.

    PubMed

    Kong, Zhaoyu; Mohamad, Osama Abdalla; Deng, Zhenshan; Liu, Xiaodong; Glick, Bernard R; Wei, Gehong

    2015-08-01

    The effects of rhizobial symbiosis on the growth, metal uptake, and antioxidant responses of Medicago lupulina in the presence of 200 mg kg(-1) Cu(2+) throughout different stages of symbiosis development were studied. The symbiosis with Sinorhizobium meliloti CCNWSX0020 induced an increase in plant growth and nitrogen content irrespective of the presence of Cu(2+). The total amount of Cu uptake of inoculated plants significantly increased by 34.0 and 120.4% in shoots and roots, respectively, compared with non-inoculated plants. However, although the rhizobial symbiosis promoted Cu accumulation both in shoots and roots, the increase in roots was much higher than in shoots, thus decreasing the translocation factor and helping Cu phytostabilization. The rate of lipid peroxidation was significantly decreased in both shoots and roots of inoculated vs. non-inoculated plants when measured either 8, 13, or 18 days post-inoculation. In comparison with non-inoculated plants, the activities of superoxide dismutase and ascorbate peroxidase of shoots of inoculated plants exposed to excess Cu were significantly elevated at different stages of symbiosis development; similar increases occurred in the activities of superoxide dismutase, catalase, and glutathione reductase of inoculated roots. The symbiosis with S. meliloti CCNWSX0020 also upregulated the corresponding genes involved in antioxidant responses in the plants treated with excess Cu. The results indicated that the rhizobial symbiosis with S. meliloti CCNWSX0020 not only enhanced plant growth and metal uptake but also improved the responses of plant antioxidant defense to excess Cu stress.

  17. Symbiosis specificity in the legume: rhizobial mutualism.

    PubMed

    Wang, Dong; Yang, Shengming; Tang, Fang; Zhu, Hongyan

    2012-03-01

    Legume plants are able to engage in root nodule symbiosis with nitrogen-fixing soil bacteria, collectively called rhizobia. This mutualistic association is highly specific, such that each rhizobial species/strain interacts with only a specific group of legumes, and vice versa. Symbiosis specificity can occur at multiple phases of the interaction, ranging from initial bacterial attachment and infection to late nodule development associated with nitrogen fixation. Genetic control of symbiosis specificity is complex, involving fine-tuned signal communication between the symbiotic partners. Here we review our current understanding of the mechanisms used by the host and bacteria to choose their symbiotic partners, with a special focus on the role that the host immunity plays in controlling the specificity of the legume - rhizobial symbiosis.

  18. The Mutual Symbiosis between Inclusive Bi-Lingual Education and Multicultural Education

    ERIC Educational Resources Information Center

    Irby, Beverly J.; Tong, Fuhui; Lara-Alecio, Rafael

    2011-01-01

    In this article the authors postulate a mutual symbiosis between multicultural and inclusive bi-lingual education. Combining bi-lingual and multicultural education to create a symbiotic relationship can stimulate reform in schools and can promote inclusive educational systems, thereby keeping native languages and cultures alive for minority…

  19. The Mutual Symbiosis between Inclusive Bi-Lingual Education and Multicultural Education

    ERIC Educational Resources Information Center

    Irby, Beverly J.; Tong, Fuhui; Lara-Alecio, Rafael

    2011-01-01

    In this article the authors postulate a mutual symbiosis between multicultural and inclusive bi-lingual education. Combining bi-lingual and multicultural education to create a symbiotic relationship can stimulate reform in schools and can promote inclusive educational systems, thereby keeping native languages and cultures alive for minority…

  20. Mutualism Persistence and Abandonment during the Evolution of the Mycorrhizal Symbiosis.

    PubMed

    Maherali, Hafiz; Oberle, Brad; Stevens, Peter F; Cornwell, William K; McGlinn, Daniel J

    2016-11-01

    Mutualistic symbioses with mycorrhizal fungi are widespread in plants. The majority of plant species associate with arbuscular mycorrhizal (AM) fungi. By contrast, the minority associate with ectomycorrhizal (EM) fungi, have abandoned the symbiosis and are nonmycorrhizal (NM), or engage in an intermediate, weakly AM symbiosis (AMNM). To understand the processes that maintain the mycorrhizal symbiosis or cause its loss, we reconstructed its evolution using a ∼3,000-species seed plant phylogeny integrated with mycorrhizal state information. Reconstruction indicated that the common ancestor of seed plants most likely associated with AM fungi and that the EM, NM, and AMNM states descended from the AM state. Direct transitions from the AM state to the EM and NM states were infrequent and generally irreversible, implying that natural selection or genetic constraint could promote stasis once a particular state evolved. However, the evolution of the NM state was more frequent via an indirect pathway through the AMNM state, suggesting that weakening of the AM symbiosis is a necessary precursor to mutualism abandonment. Nevertheless, reversions from the AMNM state back to the AM state were an order of magnitude more likely than transitions to the NM state, suggesting that natural selection favors the AM symbiosis over mutualism abandonment.

  1. Eco-Evo-Devo: developmental symbiosis and developmental plasticity as evolutionary agents.

    PubMed

    Gilbert, Scott F; Bosch, Thomas C G; Ledón-Rettig, Cristina

    2015-10-01

    The integration of research from developmental biology and ecology into evolutionary theory has given rise to a relatively new field, ecological evolutionary developmental biology (Eco-Evo-Devo). This field integrates and organizes concepts such as developmental symbiosis, developmental plasticity, genetic accommodation, extragenic inheritance and niche construction. This Review highlights the roles that developmental symbiosis and developmental plasticity have in evolution. Developmental symbiosis can generate particular organs, can produce selectable genetic variation for the entire animal, can provide mechanisms for reproductive isolation, and may have facilitated evolutionary transitions. Developmental plasticity is crucial for generating novel phenotypes, facilitating evolutionary transitions and altered ecosystem dynamics, and promoting adaptive variation through genetic accommodation and niche construction. In emphasizing such non-genomic mechanisms of selectable and heritable variation, Eco-Evo-Devo presents a new layer of evolutionary synthesis.

  2. [The attitude of physicians regarding the promotion strategies of the pharmaceutical industry].

    PubMed

    Castresana, Leonardo; Mejia, Raul; Aznar, Mireya

    2005-01-01

    Pharmaceutical companies invest large sums of money promoting their products. They use a multifaceted approach to drug promotion, incorporating techniques such as hospital and office detailing by pharmaceutical representatives. Although these practices are commonly used, little has been published about the attitude of physicians concerning their interaction with the pharmaceutical industry. We performed a cross sectional anonymous survey to identify the extent of and attitudes towards the relationship between the physicians and the pharmaceutical industry and its representatives with its impact on the knowledge, attitude and behavior of the physicians. Internists, cardiologists and dermatologists who work in ambulatory settings from private and public hospitals in Buenos Aires city participated in this study, 44% were female, 35% residents, 65% staff physicians, averaging 41 years of age. Of these, 86% receive medical samples frecuently, 39% desk gifts, 19% invitations to congresses and 12% free lunches. Half of the doctors believe that receiving benefits from the pharmaceutical industry has an influence on medical prescription, but only 27% accept this as influential in their own prescriptions. Residents consider, more frequently than others, that these activities affect their decisions, (42% vs. 18% p = 0.007, global 30%). Most of the participants consider appropriate receiving these benefits, although 35% think that they affect the final price of medications. In conclusion, there is a high level of interaction between the pharmaceutical industry and our medical population. Although the latter recognize the influence of these interactions on prescriptions and the elevation of the cost of the final product, they find it appropriate to receive benefits.

  3. Exploring How the Tobacco Industry Presents and Promotes Itself in Social Media

    PubMed Central

    Liang, Yunji; Zheng, Xiaolong; Zhou, Xingshe; Leischow, Scott James; Chung, Wingyan

    2015-01-01

    Background The commercial potential of social media is utilized by tobacco manufacturers and vendors for tobacco promotion online. However, the prevalence and promotional strategies of pro-tobacco content in social media are still not widely understood. Objective The goal of this study was to reveal what is presented by the tobacco industry, and how it promotes itself, on social media sites. Methods The top 70 popular cigarette brands are divided into two groups according to their retail prices: group H (brands with high retail prices) and group L (brands with low retail prices). Three comprehensive searches were conducted on Facebook, Wikipedia, and YouTube respectively using the top 70 popular cigarette brands as keywords. We identified tobacco-related content including history and culture, product features, health warnings, home page of cigarette brands, and Web-based tobacco shops. Furthermore, we examined the promotional strategies utilized in social media. Results According to the data collected from March 3, 2014 to March 10, 2014, 43 of the 70 representative cigarette brands had created 238 Facebook fan pages, 46 cigarette brands were identified in Wikipedia, and there were over 120,000 pro-tobacco videos on YouTube, associated with 61 cigarette brands. The main content presented on the three social media websites differs significantly. Wikipedia focuses on history and culture (67%, 32/48; P<.001). Facebook mainly covers history and culture (37%, 16/43; P<.001) and major products (35%, 15/43), while YouTube focuses on the features of major tobacco products (79%, 48/61; P=.04) and information about Web-based shops (49%, 30/61; P=.004). Concerning the content presented by groups H and L, there is no significant difference between the two groups. With regard to the promotional strategies used, sales promotions exist extensively in social media. Sales promotion is more prevalent on YouTube than on the other two sites (64%, 39/61 vs 35%, 15/43; P=.004

  4. Exploring how the tobacco industry presents and promotes itself in social media.

    PubMed

    Liang, Yunji; Zheng, Xiaolong; Zeng, Daniel Dajun; Zhou, Xingshe; Leischow, Scott James; Chung, Wingyan

    2015-01-21

    The commercial potential of social media is utilized by tobacco manufacturers and vendors for tobacco promotion online. However, the prevalence and promotional strategies of pro-tobacco content in social media are still not widely understood. The goal of this study was to reveal what is presented by the tobacco industry, and how it promotes itself, on social media sites. The top 70 popular cigarette brands are divided into two groups according to their retail prices: group H (brands with high retail prices) and group L (brands with low retail prices). Three comprehensive searches were conducted on Facebook, Wikipedia, and YouTube respectively using the top 70 popular cigarette brands as keywords. We identified tobacco-related content including history and culture, product features, health warnings, home page of cigarette brands, and Web-based tobacco shops. Furthermore, we examined the promotional strategies utilized in social media. According to the data collected from March 3, 2014 to March 10, 2014, 43 of the 70 representative cigarette brands had created 238 Facebook fan pages, 46 cigarette brands were identified in Wikipedia, and there were over 120,000 pro-tobacco videos on YouTube, associated with 61 cigarette brands. The main content presented on the three social media websites differs significantly. Wikipedia focuses on history and culture (67%, 32/48; P<.001). Facebook mainly covers history and culture (37%, 16/43; P<.001) and major products (35%, 15/43), while YouTube focuses on the features of major tobacco products (79%, 48/61; P=.04) and information about Web-based shops (49%, 30/61; P=.004). Concerning the content presented by groups H and L, there is no significant difference between the two groups. With regard to the promotional strategies used, sales promotions exist extensively in social media. Sales promotion is more prevalent on YouTube than on the other two sites (64%, 39/61 vs 35%, 15/43; P=.004). Generally, the sale promotions of higher

  5. Polyfire project- an example of an industrial research project promoting safe industrial production of fire-resistant nanocomposites

    NASA Astrophysics Data System (ADS)

    Vaquero, C.; López de Ipiña, J.; Galarza, N.; Hargreaves, B.; Weager, B.; Breen, C.

    2011-07-01

    New developments based on nanotechnology have to guarantee safe products and processes to be accepted by society. The Polyfire project will develop and scale-up techniques for processing halogen-free, fire-retardant nanocomposite materials and coatings based on unsaturated polyester resins and organoclays. The project includes a work package that will assess the Health and Environmental impacts derived from the manipulation of nanoparticles. This work package includes the following tasks: (1) Identification of Health and Environment Impacts derived from the processes, (2) Experimentation to study specific Nanoparticle Emissions, (3) Development of a Risk Management Methodology for the process, and (4) A Comparison of the Health and Environmental Impact of New and Existing Materials. To date, potential exposure scenarios to nanomaterials have been identified through the development of a Preliminary Hazard Analysis (PHA) of the new production processes. In the next step, these scenarios will be studied and simulated to evaluate potential emissions of nanomaterials. Polyfire is a collaborative European project, funded by the European Commission 7th Framework Programme (Grant Agreement No 229220). It features 11 partners from 5 countries (5 SMEs, 3 research institutes, 2 large companies, 1 association) and runs for three years (1st September 2009 - 31st August 2012). This project is an example of an industrial research development which aims to introduce to the market new products promoting the safe use of nanomaterials.

  6. Promotion by the British pharmaceutical industry, 1983-8: a critical analysis of self regulation.

    PubMed Central

    Herxheimer, A; Collier, J

    1990-01-01

    Since 1958 the Association of the British Pharmaceutical Industry (ABPI) has attempted to regulate the promotion of prescription medicines through its code of practice. This regulation is described and analysed for the six years 1983-8 using the reports on 302 complaints considered by its code of practice committee and annual reports. The complaints came mainly from doctors (143, 48%) and competing companies (103, 33%). The committee found a total of 379 breaches of the code in 192 (63%) of the complaints. Additional breaches were detected by informational scrutiny of advertisements by the ABPI secretariat. Analysis showed that 270 (71%) of these breaches involved possible breaches of the Medicines Act. The rules that forbid misleading or unsubstantiated information and misleading claims or comparisons were broken most often. The committee found the most frequent offenders to be Organon (32 breaches), Smith Kline and French (23), Glaxo (21), A H Robins (18), Bayer (17), Merck Sharp and Dohme (17), and Lederle (16). Often the promotion of one product led to several breaches. The promotional wars over histamine H2 receptor antagonists accounted for 33 breaches. It is estimated that in 1983-8 about 100 breaches of the code were detected a year. In the 18 years 1972-88 the Medicines Act was breached probably over 1200 times. Health ministers, by not enforcing the regulations controlling promotion, have abrogated their responsibility to the ABPI, but the evidence suggests that the code has failed to deter promotional excesses. The ABPI's wish to secure compliance with the code seems weaker than its wish to pre-empt outside criticism and action: its self regulation seems to be a service to itself rather than to the public. It is suggested that the code of practice committee should become publicly accountable, that the majority of its members should represent the health professions and the public, and that effective sanctions are needed. PMID:2106963

  7. Promotion by the British pharmaceutical industry, 1983-8: a critical analysis of self regulation.

    PubMed

    Herxheimer, A; Collier, J

    1990-02-03

    Since 1958 the Association of the British Pharmaceutical Industry (ABPI) has attempted to regulate the promotion of prescription medicines through its code of practice. This regulation is described and analysed for the six years 1983-8 using the reports on 302 complaints considered by its code of practice committee and annual reports. The complaints came mainly from doctors (143, 48%) and competing companies (103, 33%). The committee found a total of 379 breaches of the code in 192 (63%) of the complaints. Additional breaches were detected by informational scrutiny of advertisements by the ABPI secretariat. Analysis showed that 270 (71%) of these breaches involved possible breaches of the Medicines Act. The rules that forbid misleading or unsubstantiated information and misleading claims or comparisons were broken most often. The committee found the most frequent offenders to be Organon (32 breaches), Smith Kline and French (23), Glaxo (21), A H Robins (18), Bayer (17), Merck Sharp and Dohme (17), and Lederle (16). Often the promotion of one product led to several breaches. The promotional wars over histamine H2 receptor antagonists accounted for 33 breaches. It is estimated that in 1983-8 about 100 breaches of the code were detected a year. In the 18 years 1972-88 the Medicines Act was breached probably over 1200 times. Health ministers, by not enforcing the regulations controlling promotion, have abrogated their responsibility to the ABPI, but the evidence suggests that the code has failed to deter promotional excesses. The ABPI's wish to secure compliance with the code seems weaker than its wish to pre-empt outside criticism and action: its self regulation seems to be a service to itself rather than to the public. It is suggested that the code of practice committee should become publicly accountable, that the majority of its members should represent the health professions and the public, and that effective sanctions are needed.

  8. Are informed policies in place to promote safe and usable EHRs? A cross-industry comparison.

    PubMed

    Savage, Erica L; Fairbanks, Rollin J; Ratwani, Raj M

    2017-02-19

    Despite federal policies put in place by the Office of the National Coordinator (ONC) to promote safe and usable electronic health record (EHR) products, the usability of EHRs continues to frustrate providers and have patient safety implications. This study sought to compare government policies on usability and safety, and methods of examining compliance to those policies, across 3 federal agencies: the ONC and EHRs, the Federal Aviation Administration (FAA) and avionics, and the Food and Drug Administration (FDA) and medical devices. Our goal was to identify whether differences in policies exist and, if they do exist, how policies and enforcement mechanisms from other industries might be applied to optimize EHR usability. We performed a qualitative study using publicly available governing documents to examine similarities and differences in usability and safety policies across agencies. The policy review and analysis revealed several consistencies within each agency's usability policies. Critical differences emerged in the usability standards and policy enforcement mechanisms utilized by the 3 agencies. The FAA and FDA look at evidence of usability processes and are more prescriptive when it comes to testing final products as compared to the ONC, which relies on attestation and is less prescriptive. A comparison of usability policies across industries illustrates key differences between the ONC and other federal agencies. These differences could be contributing to the usability challenges associated with EHRs. Our analysis highlights important areas of usability and safety policy from other industries that can better inform ONC policies on EHRs.

  9. How state counter-industry campaigns help prime perceptions of tobacco industry practices to promote reductions in youth smoking

    PubMed Central

    Hersey, J; Niederdeppe, J; Ng, S; Mowery, P; Farrelly, M; Messeri, P

    2005-01-01

    Methods: Rates of youth smoking were compared in three groups of states: (1) those with long funded counter-industry campaigns (California, Florida, and Massachusetts); (2) states with more recently funded counter-industry media campaigns (Indiana, Minnesota, Mississippi, and New Jersey); and (3) other states. An analysis was performed for a series of national telephone surveys of 12–17 year olds between 1999 and 2002, controlling for differences in demographic background, the price of cigarettes, and exposure to the national truth® campaign. Results: Between 1999 and 2002, rates of current smoking and established smoking decreased significantly faster in states with established or more newly funded counter-industry campaigns than in other states. State counter-industry campaigns appear to prime, or make more salient, negative perceptions about tobacco industry practices. Conclusion: Results highlight the value of continued state counter-industry campaigns. PMID:16319360

  10. Agro-food industry growth and obesity in China: what role for regulating food advertising and promotion and nutrition labelling?

    PubMed

    Hawkes, C

    2008-03-01

    Taking a food supply chain approach, this paper examines the regulation of food marketing and nutrition labelling as strategies to help combat obesity in China in an era of rapid agro-food industry growth. China is the largest food producer and consumer in the world. Since the early 1980s, the agro-food industry has undergone phenomenal expansion throughout the food supply chain, from agricultural production to trade, agro-food processing to food retailing, and from food service to advertising and promotion. This industry growth, alongside related socioeconomic changes and government policies, has encouraged a 'nutrition transition'. China's population, especially in urban areas, is now consuming significantly more energy from dietary fat, which is leading to higher rates of obesity. Regulation of food advertising and promotion and nutrition labelling has the potential to help prevent the further growth of obesity in China and encourage the agro-food industry to supplier healthier foods. Government legislation and guidance, as well as self-regulation and voluntary initiatives, are needed to reduce children's exposure to food advertising and promotion, and increase the effectiveness of nutrition labelling. Policies on food marketing and nutrition labelling should be adapted to the China context, and accompanied by further action throughout the food supply chain. Given China's unique characteristics and position in the world today, there is an opportunity for the government and the agro-food industry to lead the world by creating a balanced, health promoting model of complementary legislation and industry action.

  11. Plant hormones as signals in arbuscular mycorrhizal symbiosis.

    PubMed

    Miransari, Mohammad; Abrishamchi, A; Khoshbakht, K; Niknam, V

    2014-06-01

    Arbuscular mycorrhizal (AM) fungi are non-specific symbionts developing mutual and beneficial symbiosis with most terrestrial plants. Because of the obligatory nature of the symbiosis, the presence of the host plant during the onset and proceeding of symbiosis is necessary. However, AM fungal spores are able to germinate in the absence of the host plant. The fungi detect the presence of the host plant through some signal communications. Among the signal molecules, which can affect mycorrhizal symbiosis are plant hormones, which may positively or adversely affect the symbiosis. In this review article, some of the most recent findings regarding the signaling effects of plant hormones, on mycorrhizal fungal symbiosis are reviewed. This may be useful for the production of plants, which are more responsive to mycorrhizal symbiosis under stress.

  12. Unethical and Deadly Symbiosis in Higher Education

    ERIC Educational Resources Information Center

    Crumbley, D. Larry; Flinn, Ronald; Reichelt, Kenneth J.

    2012-01-01

    As administrators are pressured to increase retention rates in accounting departments, and higher education in general, a deadly symbiosis is occurring. Most students and parents only wish for high grades, so year after year many educators engage in unethical grade inflation and course work deflation. Since administrators use the students to audit…

  13. Unethical and Deadly Symbiosis in Higher Education

    ERIC Educational Resources Information Center

    Crumbley, D. Larry; Flinn, Ronald; Reichelt, Kenneth J.

    2012-01-01

    As administrators are pressured to increase retention rates in accounting departments, and higher education in general, a deadly symbiosis is occurring. Most students and parents only wish for high grades, so year after year many educators engage in unethical grade inflation and course work deflation. Since administrators use the students to audit…

  14. Novel multifunctional plant growth-promoting bacteria in co-compost of palm oil industry waste.

    PubMed

    Chin, Clament Fui Seung; Furuya, Yoshihide; Zainudin, Mohd Huzairi Mohd; Ramli, Norhayati; Hassan, Mohd Ali; Tashiro, Yukihiro; Sakai, Kenji

    2017-07-20

    Previously, a unique co-compost produced by composting empty fruit bunch with anaerobic sludge from palm oil mill effluent, which contributed to establishing a zero-emission industry in Malaysia. Little was known about the bacterial functions during the composting process and fertilization capacity of this co-compost. We isolated 100 strains from the co-compost on 7 types of enumeration media and screened 25 strains using in vitro tests for 12 traits, grouping them according to three functions: plant growth promoting (fixation of nitrogen; solubilization of phosphorus, potassium, and silicate; production of 3-indoleacetic acid, ammonia, and siderophore), biocontrolling (production of chitinase and anti-Ganoderma activity), and composting (degradation of lignin, xylan, and cellulose). Using 16S rRNA gene sequence analysis, 25 strains with strong or multi-functional traits were found belong to the genera Bacillus, Paenibacillus, Citrobacter, Enterobacter, and Kosakonia. Furthermore, several strains of Citrobactersedlakii exhibited a plant growth-stimulation in vivo komatsuna plant cultivation test. In addition, we isolated several multifunctional strains; Bacillustequilensis CE4 (biocontrolling and composting), Enterobactercloacae subsp. dissolvens B3 (plant growth promoting and biocontrolling), and C. sedlakii CESi7 (plant growth promoting and composting). Some bacteria in the co-compost play significant roles during the composting process and plant cultivation after fertilization, and some multifunctional strains have potential for use in accelerating the biodegradation of lignocellulosic biomass, protecting against Ganodermaboninense infection, and increasing the yield of palm oil. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  15. Practical Application of Methanol-Mediated Mutualistic Symbiosis between Methylobacterium Species and a Roof Greening Moss, Racomitrium japonicum

    PubMed Central

    Tani, Akio; Takai, Yuichiro; Suzukawa, Ikko; Akita, Motomu; Murase, Haruhiko; Kimbara, Kazuhide

    2012-01-01

    Bryophytes, or mosses, are considered the most maintenance-free materials for roof greening. Racomitrium species are most often used due to their high tolerance to desiccation. Because they grow slowly, a technology for forcing their growth is desired. We succeeded in the efficient production of R. japonicum in liquid culture. The structure of the microbial community is crucial to stabilize the culture. A culture-independent technique revealed that the cultures contain methylotrophic bacteria. Using yeast cells that fluoresce in the presence of methanol, methanol emission from the moss was confirmed, suggesting that it is an important carbon and energy source for the bacteria. We isolated Methylobacterium species from the liquid culture and studied their characteristics. The isolates were able to strongly promote the growth of some mosses including R. japonicum and seed plants, but the plant-microbe combination was important, since growth promotion was not uniform across species. One of the isolates, strain 22A, was cultivated with R. japonicum in liquid culture and in a field experiment, resulting in strong growth promotion. Mutualistic symbiosis can thus be utilized for industrial moss production. PMID:22479445

  16. Practical application of methanol-mediated mutualistic symbiosis between Methylobacterium species and a roof greening moss, Racomitrium japonicum.

    PubMed

    Tani, Akio; Takai, Yuichiro; Suzukawa, Ikko; Akita, Motomu; Murase, Haruhiko; Kimbara, Kazuhide

    2012-01-01

    Bryophytes, or mosses, are considered the most maintenance-free materials for roof greening. Racomitrium species are most often used due to their high tolerance to desiccation. Because they grow slowly, a technology for forcing their growth is desired. We succeeded in the efficient production of R. japonicum in liquid culture. The structure of the microbial community is crucial to stabilize the culture. A culture-independent technique revealed that the cultures contain methylotrophic bacteria. Using yeast cells that fluoresce in the presence of methanol, methanol emission from the moss was confirmed, suggesting that it is an important carbon and energy source for the bacteria. We isolated Methylobacterium species from the liquid culture and studied their characteristics. The isolates were able to strongly promote the growth of some mosses including R. japonicum and seed plants, but the plant-microbe combination was important, since growth promotion was not uniform across species. One of the isolates, strain 22A, was cultivated with R. japonicum in liquid culture and in a field experiment, resulting in strong growth promotion. Mutualistic symbiosis can thus be utilized for industrial moss production.

  17. 'It's interesting how few people die from smoking': tobacco industry efforts to minimize risk and discredit health promotion.

    PubMed

    Smith, Elizabeth A

    2007-04-01

    It is well known that the tobacco industry has placed articles in scientific literature to maintain controversy over the dangers of tobacco use, while claiming that smokers are well-informed about risk. This study illuminates an industry attempt to directly undermine popular understanding of the hazards of smoking using an industry-created organization called Associates for Research in the Science of Enjoyment (ARISE). Searches of tobacco industry documents contained in the Legacy Tobacco Documents Library, British American Tobacco Documents Library, and British Columbia's Tobacco Industry documents were performed as well as searches of the LexisNexis database for news articles on ARISE published between 1989 and 2005. Qualitative analysis focused on industry motives, media strategies, and rhetorical tactics; quantitative content analysis focused on media coverage. Between 1989 and 2005, at least 846 articles appeared in the European, Australian, and US press mentioning ARISE, its members, or its activities. Many of these articles presented two themes: smoking was a healthful 'pleasure', and health promotion practices, including cessation, were stressful and unhealthy. Few articles included responses from health advocates, questioned ARISE's claims, or mentioned its funding. ARISE successfully planted stories in the press, designed to allay the health concerns of smokers and to discredit health promotion information and practices. ARISE's later interest in food suggests that counterfactual 'health' messages on almost any topic could be promoted similarly, regardless of their implausibility.

  18. Arbuscular mycorrhizal symbiosis induces strigolactone biosynthesis under drought and improves drought tolerance in lettuce and tomato.

    PubMed

    Ruiz-Lozano, Juan Manuel; Aroca, Ricardo; Zamarreño, Ángel María; Molina, Sonia; Andreo-Jiménez, Beatriz; Porcel, Rosa; García-Mina, José María; Ruyter-Spira, Carolien; López-Ráez, Juan Antonio

    2016-02-01

    Arbuscular mycorrhizal (AM) symbiosis alleviates drought stress in plants. However, the intimate mechanisms involved, as well as its effect on the production of signalling molecules associated with the host plant-AM fungus interaction remains largely unknown. In the present work, the effects of drought on lettuce and tomato plant performance and hormone levels were investigated in non-AM and AM plants. Three different water regimes were applied, and their effects were analysed over time. AM plants showed an improved growth rate and efficiency of photosystem II than non-AM plants under drought from very early stages of plant colonization. The levels of the phytohormone abscisic acid, as well as the expression of the corresponding marker genes, were influenced by drought stress in non-AM and AM plants. The levels of strigolactones and the expression of corresponding marker genes were affected by both AM symbiosis and drought. The results suggest that AM symbiosis alleviates drought stress by altering the hormonal profiles and affecting plant physiology in the host plant. In addition, a correlation between AM root colonization, strigolactone levels and drought severity is shown, suggesting that under these unfavourable conditions, plants might increase strigolactone production in order to promote symbiosis establishment to cope with the stress.

  19. Developing environmental legislation to promote recycling of industrial by-products - an endless story?

    PubMed

    Sorvari, Jaana

    2008-01-01

    In Finland during the last few decades, mineral industrial residues (by-products) have been used in earthworks, but only to a limited extent relative to their total volume. The most important barrier to efficient recycling of by-products has been the need for a site-specific environmental permit, since the permit process tends to be time-consuming and laborious. In 2000 a working group was set up to prepare national legislation, i.e., a Government decree, in order to promote the use of by-products in earth construction. The aim was to exempt certain residues from the environmental permit obligation. At the first stage, the working group determined specific decision criteria for the selection of the by-products to be included. For the selected residues, the acceptable construction applications and material-specific environmental standards were defined. Various difficulties were encountered during the preparation of the decree. These were mainly caused by the lack of data and by some ongoing changes in environmental regulations. Furthermore, the draft decree received several critical and partly contradictory comments and proposals for amendments. This resulted in considerable delay in implementation.

  20. Industry experience in promoting weekly iron-folic acid supplementation in the Philippines.

    PubMed

    Garcia, Josel; Datol-Barrett, Eva; Dizon, Maynilad

    2005-12-01

    After participating in a pilot project under a government-industry partnership to promote the adoption of weekly iron-folic acid supplementation among women of reproductive age in the Philippines in 1998, United Laboratories (UNILAB), the Philippines' largest private pharmaceutical company, decided in April 2002 to launch a weekly iron-folic acid supplement for pregnant and non-pregnant women under the brand name Femina. The business objective set for the Femina brand was to build the category of preventive iron-folic acid supplements in line with the Philippine Department of Health's advocacy on weekly supplementation as an alternate to daily dosing to reduce the prevalence of anemia in the country. The brand was supported with an integrated mix of traditional advertising media with complementary direct-to-consumer educational programs that aimed to create awareness of iron-deficiency anemia, its causes and effects, and the role of weekly intake of iron-folic acid in preventing the condition. Aggressive marketing support for 1 year was successful in creating awareness among the target women. Significant lessons derived from consumers identified opportunity areas that can be further addressed in developing advocacy programs on weekly iron supplementation implemented on a nationwide scale in the future.

  1. Travel Health Advisory Group: a joint travel industry and travel health Special Interest Group promoting healthy travel in Australia.

    PubMed

    Leggat, Peter A; Zwar, Nicholas; Hudson, Bernie

    2012-09-01

    The Travel Health Advisory Group (THAG), established in 1997, is a joint initiative between the travel industry and travel health professionals in Australia that aims to promote healthy travel. THAG seeks to promote cooperation in improving the health of travellers between the travel industry and travel medicine professionals and to raise public awareness of the importance of travel health. From 2011, THAG has been a Special Interest Group of The Australasian College of Tropical Medicine and its membership has been active in several areas, including web-based travel health information, travel health promotion, media releases, research and education in Australia. Information is given on the objectives, membership and an overview of the various activities of the group.

  2. 7 CFR 1260.169 - Promotion, research, consumer information and industry information.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Promotion, research, consumer information and... (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE BEEF PROMOTION AND RESEARCH Beef Promotion and Research Order Beef Promotion...

  3. Computer symbiosis: Emergence of symbiotic behavior through evolution

    SciTech Connect

    Ikegami, Takashi; Kaneko, Kunihiko

    1989-01-01

    Symbiosis is altruistic cooperation between distinct species. It is one of the most effective evolutionary processes, but its dynamics are not well understood as yet. A simple model of symbiosis is introduced, where we consider interactions between hosts and parasites and also mutations of hosts and parasites. It is found that a symbiotic state emerges for a suitable range of mutation rates. The symbiotic state is not static, but dynamically oscillates. Harmful parasites violating symbiosis appear periodically, but are rapidly extinguished by hosts and other parasites, and the symbiotic state is recovered. The emergence of ''Tit for Tat'' strategy to maintain symbiosis is discussed. 4 figs.

  4. Not Waiting for Godot: The Evolution of Health Promotion at PPG Industries.

    PubMed

    Colombi, Alberto M; Pringle, Janice L; Welsh, George T

    2008-04-01

    PPG Industries is a manufacturer of coatings, chemicals, optical products, specialty materials, glass, and fiberglass. The company's approach to healthcare combines perhaps 2 disparate concepts. The first is that employee health and behavior change relies to a large degree on employee awareness and ownership of their own health and second that "what gets measured gets done." It is widely acknowledged that one of the best tools for employee awareness is the health risk appraisal tool. Additional components of employee awareness include knowing key individual health metrics and effectively engaging with healthcare providers. As a leading global manufacturer, PPG well understands the critical importance of cost accounting and financial metrics to drive business decisions. PPG's perhaps unique approach comes from the strong marriage of individual health/wellness promotion and frequent, timely, and informative financial metrics on health and the cost of care. Combining capacity building through the mobilization of volunteer wellness teams with expert interventions and financial discipline is a feature of the experience here described. This approach has resulted in both management and employee engagement in the issue and has allowed PPG to bend the curve of ever-increasing healthcare costs and achieve cost increases per employee at one half the reported national average for companies of comparable size. Because this journal is dedicated to health and drug benefits, we gathered an appropriately representative team composed of a physician, an epidemiologist who resides in a pharmacy school, and a benefits manager. The team evolved from a common vision to identify ways of improving employee health and well-being. The team presented both as keynote speakers and as contributors to a breakout session at the National Symposium on Work-Life organized in 2007 by the National Institute for Occupational Safety and Health, a federal agency of the Centers for Disease Control and

  5. Arbuscular mycorrhizal fungi in terms of symbiosis-parasitism continuum.

    PubMed

    Schmidt, B; Gaşpar, S; Camen, D; Ciobanu, I; Sumălan, R

    2011-01-01

    Arbuscular mycorrhizal fungi are forming the most wide-spread mycorrhizal relationships on Earth. Mycorrhiza contributes to phosphorous acquisition, water absorption and resistance to diseases. The fungus promotes the absorption of nutrients and water from soil, meanwhile the host plant offers photosynthetic assimilates in exchange, like carbohydrates, as energy source. The plant benefits from the contribution of symbiotic partner only when nutrients are in low concentrations in soil and the root system would not be able to absorb sufficiently the minerals. When the help of mycorrhizal fungi is not necessarily needed, the host plant is making an economy of energy, suppressing the development of fungi in the internal radicular space. In this moment, the nature of relationship turns from symbiotic to parasitic, triggering a series of defensive reactions from the plant. Also, there were several cases reported when the presence of arbuscular mycorrhizal fungi negatively influenced the host plant. For example, in adverse environmental conditions, like very high temperatures, instead of determining a higher plant biomass and flowering, the mycorrhiza reduces the growth of the host plant. We conducted a pot experiment with hydroponic culture to examine the effect of arbuscular mycorrhiza on development of French marigold as a host plant. As experimental variants, the phosphorous content in nutrient medium and temperature varied. Plants were artificially infected with arbuscular mycorrhizal fungi using a commercial inoculum containing three fungal species, as following: Glomus intraradices, Glomus etunicatum and Glomus claroideum. Colonization intensity and arbuscular richness were checked using root staining with aniline blue and estimation with the Trouvelot method. To observe the differences between plants from the experimental variants, we examined the number of side shoots, flower buds and fully developed flowers, fresh biomass and total leaf area. Results show that

  6. 7 CFR 1220.230 - Promotion, research, consumer information, and industry information.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., marketing and utilization of soybean and soybean products and the creation of new products thereof, to the... 7 Agriculture 10 2010-01-01 2010-01-01 false Promotion, research, consumer information, and...), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and...

  7. Femtosecond laser-fabricated biochip for studying symbiosis between Phormidium and seedling root

    NASA Astrophysics Data System (ADS)

    Ishikawa, Nobuaki; Hanada, Yasutaka; Ishikawa, Ikuko; Sugioka, Koji; Midorikawa, Katsumi

    2015-06-01

    We present the fabrication of a waveguide-like structure in a polydimethylsiloxane (PDMS) polymer substrate using a femtosecond laser to study the mechanism of symbiosis between filamentous cyanobacteria, Phormidium, and a seedling root. While symbiosis occurring underground promotes the growth of vegetable seedlings, the details of the mechanism remain unclear. Understanding the mechanisms of Phormidium gliding to the seedling root will facilitate improving the mat formation of Phormidium, which will lead to increased vegetable production. We assumed a symbiosis mechanism in which sunlight propagates through the seedling root and is scattered underground to guide the Phormidium gliding. Once attached to the root, Phormidium uses the scattered light for photosynthesis. Photosynthetic products, in turn, promote an increase in Phormidium mat formation and vegetable growth. To verify this assumption, the optical characteristics of the seedling root were investigated. A waveguide-like structure with the same optical characteristics of the root was subsequently fabricated by femtosecond laser in PDMS polymer to assess the light illumination effect on Phormidium behavior.

  8. Promoting creativity in the electric utility industry under a regulated and/or de-regulated environment

    SciTech Connect

    Riley, H.W. Jr.

    1996-12-31

    Over the years, utilities have been going through cost cutting measures and efficiency improvements in an effort to be more competitive or stay competitive within their market territory. The next logical step for a utility to take is to promote Creativity. With a creative environment in place, utilities can keep pace with the changes in the industry and maintain or attain their competitive advantage. The goal of the creative electric utility work-force is to keep up with changes in the industry and become more competitive as the market becomes more competitive. Utilities can change the way they do business by utilizing an effectively trained and skilled work-force on the subject of creative thinking. Creativity within a work-force depends on the employees desire to understand difficult aspects of his or her life. This paper will provide the foundation for linking Creativity and the electric utility industry.

  9. Workplace Health Promotion Implementation, Readiness, and Capacity Among Mid-Sized Employers in Low-Wage Industries: A National Survey

    PubMed Central

    Hannon, Peggy A.; Garson, Gayle; Harris, Jeffrey R.; Hammerback, Kristen; Sopher, Carrie J.; Clegg-Thorp, Catherine

    2012-01-01

    Objective To describe workplace health promotion (WHP) implementation, readiness, and capacity among mid-sized employers in low-wage industries in the United States. Methods A cross-sectional survey of a national sample of mid-sized employers (100–4,999 employees) representing five low-wage industries. Results Employers’ WHP implementation for both employees and employees’ spouses and partners was low. Readiness scales showed that employers believe WHP would benefit their employees and their companies, but they were less likely to believe that WHP was feasible for their companies. Employers’ capacity to implement WHP was very low; nearly half the sample reported no capacity. Conclusion Mid-sized employers in low-wage industries implement few WHP programs; their responses to readiness and capacity measures indicate that low capacity may be one of the principal barriers to WHP implementation. PMID:23090160

  10. A model of Occupational Safety and Health Management System (OSHMS) for promoting and controlling health and safety in textile industry.

    PubMed

    Manimaran, S; Rajalakshmi, R; Bhagyalakshmi, K

    2015-01-01

    The development of Occupational Safety and Health Management System in textile industry will rejuvenate the workers and energize the economy as a whole. In India, especially in Tamil Nadu, approximately 1371 textile business is running with the help of 38,461 workers under Ginning, Spinning, Weaving, Garment and Dyeing sectors. Textile industry of contributes to the growth of Indian economy but it fails to foster education and health as key components of human development and help new democracies. The present work attempts to measure and develop OSHMS which reduce the hazards and risk involved in textile industry. Among all other industries textile industry is affected by enormous hazards and risk because of negligence by management and Government. It is evident that managements are not abiding by law when an accident has occurred. Managements are easily deceiving workers and least bothered about the Quality of Work Life (QWL). A detailed analysis of factors promoting safety and health to the workers has been done by performing confirmatory factor analysis, evaluating Risk Priority Number and the framework of OHMS has been conceptualized using Structural Equation Model. The data have been collected using questionnaire and interview method. The study finds occupation health for worker in Textile industry is affected not only by safety measure but also by technology and management. The work shows that difficulty in identifying the cause and effect of hazards, the influence of management in controlling and promoting OSHMS under various dimensions. One startling fact is existence of very low and insignificance correlation between health factors and outcome.

  11. Reciprocal genomic evolution in the ant–fungus agricultural symbiosis

    PubMed Central

    Nygaard, Sanne; Hu, Haofu; Li, Cai; Schiøtt, Morten; Chen, Zhensheng; Yang, Zhikai; Xie, Qiaolin; Ma, Chunyu; Deng, Yuan; Dikow, Rebecca B.; Rabeling, Christian; Nash, David R.; Wcislo, William T.; Brady, Seán G.; Schultz, Ted R.; Zhang, Guojie; Boomsma, Jacobus J.

    2016-01-01

    The attine ant–fungus agricultural symbiosis evolved over tens of millions of years, producing complex societies with industrial-scale farming analogous to that of humans. Here we document reciprocal shifts in the genomes and transcriptomes of seven fungus-farming ant species and their fungal cultivars. We show that ant subsistence farming probably originated in the early Tertiary (55–60 MYA), followed by further transitions to the farming of fully domesticated cultivars and leaf-cutting, both arising earlier than previously estimated. Evolutionary modifications in the ants include unprecedented rates of genome-wide structural rearrangement, early loss of arginine biosynthesis and positive selection on chitinase pathways. Modifications of fungal cultivars include loss of a key ligninase domain, changes in chitin synthesis and a reduction in carbohydrate-degrading enzymes as the ants gradually transitioned to functional herbivory. In contrast to human farming, increasing dependence on a single cultivar lineage appears to have been essential to the origin of industrial-scale ant agriculture. PMID:27436133

  12. Modeling symbiosis by interactions through species carrying capacities

    NASA Astrophysics Data System (ADS)

    Yukalov, V. I.; Yukalova, E. P.; Sornette, D.

    2012-08-01

    We introduce a mathematical model of symbiosis between different species by taking into account the influence of each species on the carrying capacities of the others. The modeled entities can pertain to biological and ecological societies or to social, economic and financial societies. Our model includes three basic types: symbiosis with direct mutual interactions, symbiosis with asymmetric interactions, and symbiosis without direct interactions. In all cases, we provide a complete classification of all admissible dynamical regimes. The proposed model of symbiosis turned out to be very rich, as it exhibits four qualitatively different regimes: convergence to stationary states, unbounded exponential growth, finite-time singularity, and finite-time death or extinction of species.

  13. Industry

    SciTech Connect

    Bernstein, Lenny; Roy, Joyashree; Delhotal, K. Casey; Harnisch, Jochen; Matsuhashi, Ryuji; Price, Lynn; Tanaka, Kanako; Worrell, Ernst; Yamba, Francis; Fengqi, Zhou; de la Rue du Can, Stephane; Gielen, Dolf; Joosen, Suzanne; Konar, Manaswita; Matysek, Anna; Miner, Reid; Okazaki, Teruo; Sanders, Johan; Sheinbaum Parado, Claudia

    2007-12-01

    This chapter addresses past, ongoing, and short (to 2010) and medium-term (to 2030) future actions that can be taken to mitigate GHG emissions from the manufacturing and process industries. Globally, and in most countries, CO{sub 2} accounts for more than 90% of CO{sub 2}-eq GHG emissions from the industrial sector (Price et al., 2006; US EPA, 2006b). These CO{sub 2} emissions arise from three sources: (1) the use of fossil fuels for energy, either directly by industry for heat and power generation or indirectly in the generation of purchased electricity and steam; (2) non-energy uses of fossil fuels in chemical processing and metal smelting; and (3) non-fossil fuel sources, for example cement and lime manufacture. Industrial processes also emit other GHGs, e.g.: (1) Nitrous oxide (N{sub 2}O) is emitted as a byproduct of adipic acid, nitric acid and caprolactam production; (2) HFC-23 is emitted as a byproduct of HCFC-22 production, a refrigerant, and also used in fluoroplastics manufacture; (3) Perfluorocarbons (PFCs) are emitted as byproducts of aluminium smelting and in semiconductor manufacture; (4) Sulphur hexafluoride (SF{sub 6}) is emitted in the manufacture, use and, decommissioning of gas insulated electrical switchgear, during the production of flat screen panels and semiconductors, from magnesium die casting and other industrial applications; (5) Methane (CH{sub 4}) is emitted as a byproduct of some chemical processes; and (6) CH{sub 4} and N{sub 2}O can be emitted by food industry waste streams. Many GHG emission mitigation options have been developed for the industrial sector. They fall into three categories: operating procedures, sector-wide technologies and process-specific technologies. A sampling of these options is discussed in Sections 7.2-7.4. The short- and medium-term potential for and cost of all classes of options are discussed in Section 7.5, barriers to the application of these options are addressed in Section 7.6 and the implication of

  14. Promotion

    PubMed Central

    Alam, Hasan B.

    2013-01-01

    This article gives an overview of the promotion process in an academic medical center. A description of different promotional tracks, tenure and endowed chairs, and the process of submitting an application is provided. Finally, some practical advice about developing skills and attributes that can help with academic growth and promotion is dispensed. PMID:24436683

  15. The case for responsibility of the IT industry to promote equality for women in computing.

    PubMed

    Turner, E

    2001-04-01

    This paper investigates the relationship between the role that information technology (IT) has played in the development of women's employment, the possibility of women having a significant influence on the technology's development, and the way that the IT industry perceives women as computer scientists, users and consumers. The industry's perception of women and men is investigated through the portrayal of them in computing advertisements. While women are increasingly updating their technological skills and know-how, and through this process are entering some positions in the workplace traditionally occupied by men, these achievements are not mirrored in their social and occupational status. The computer industry and higher education have worryingly low numbers of women, while the possibility of women influencing the development of computer technology is just emerging in feminist research. This paper argues that, though the IT industry, through their self-regulatory codes, subscribes to equal treatment of sexes, races and persons with disabilities, the industry nevertheless paints a stereotyped picture of inequality when portraying men and women in computer advertisements. As long as such a perception of women prevails within the industry, it will stand as a barrier to women having equal access to computer technology. If advertisements influence the way society perceives major social constructs and issues, then the computing industry has a social responsibility to portray men and women in an equal and non-stereotypical fashion.

  16. Promoting the Success of US Industry/University Research Centres. The Role of Leadership.

    ERIC Educational Resources Information Center

    Tornatzky, Louis; Lovelace, Kay; Gray, Denis O.; Walters, S. George; Geisler, Eliezer

    1999-01-01

    Leadership in industry-university research centers often involves helping constituencies with conflicting priorities deal with challenges, necessitating a participatory leadership style. Other challenges include exercising intrapreneurship, creating a compelling technical vision, and spanning organizational boundaries. (SK)

  17. Mastering ectomycorrhizal symbiosis: the impact of carbohydrates.

    PubMed

    Nehls, Uwe

    2008-01-01

    Mycorrhiza formation is the consequence of a mutualistic interaction between certain soil fungi and plant roots that helps to overcome nutritional limitations faced by the respective partners. In symbiosis, fungi contribute to tree nutrition by means of mineral weathering and mobilization of nutrients from organic matter, and obtain plant-derived carbohydrates as a response. Support with easily degradable carbohydrates seems to be the driving force for fungi to undergo this type of interaction. As a consequence, the fungal hexose uptake capacity is strongly increased in Hartig net hyphae of the model fungi Amanita muscaria and Laccaria bicolor. Next to fast carbohydrate uptake and metabolism, storage carbohydrates are of special interest. In functional A. muscaria ectomycorrhizas, expression and activity of proteins involved in trehalose biosynthesis is mainly localized in hyphae of the Hartig net, indicating an important function of trehalose in generation of a strong carbon sink by fungal hyphae. In symbiosis, fungal partners receive up to approximately 19 times more carbohydrates from their hosts than normal leakage of the root system would cause, resulting in a strong carbohydrate demand of infected roots and, as a consequence, a more efficient plant photosynthesis. To avoid fungal parasitism, the plant seems to have developed mechanisms to control carbohydrate drain towards the fungal partner and link it to the fungus-derived mineral nutrition. In this contribution, current knowledge on fungal strategies to obtain carbohydrates from its host and plant strategies to enable, but also to control and restrict (under certain conditions), carbon transfer are summarized.

  18. Microfungal "weeds" in the leafcutter ant symbiosis.

    PubMed

    Rodrigues, A; Bacci, M; Mueller, U G; Ortiz, A; Pagnocca, F C

    2008-11-01

    Leafcutter ants (Formicidae: tribe Attini) are well-known insects that cultivate basidiomycete fungi (Agaricales: Lepiotaceae) as their principal food. Fungus gardens are monocultures of a single cultivar strain, but they also harbor a diverse assemblage of additional microbes with largely unknown roles in the symbiosis. Cultivar-attacking microfungi in the genus Escovopsis are specialized parasites found only in association with attine gardens. Evolutionary theory predicts that the low genetic diversity in monocultures should render ant gardens susceptible to a wide range of diseases, and additional parasites with roles similar to that of Escovopsis are expected to exist. We profiled the diversity of cultivable microfungi found in 37 nests from ten Acromyrmex species from Southern Brazil and compared this diversity to published surveys. Our study revealed a total of 85 microfungal strains. Fusarium oxysporum and Escovopsis were the predominant species in the surveyed gardens, infecting 40.5% and 27% of the nests, respectively. No specific relationship existed regarding microfungal species and ant-host species, ant substrate preference (dicot versus grass) or nesting habit. Molecular data indicated high genetic diversity among Escovopsis isolates. In contrast to the garden parasite, F. oxysporum strains are not specific parasites of the cultivated fungus because strains isolated from attine gardens have similar counterparts found in the environment. Overall, the survey indicates that saprophytic microfungi are prevalent in South American leafcutter ants. We discuss the antagonistic potential of these microorganisms as "weeds" in the ant-fungus symbiosis.

  19. Cross sectional survey on association between alcohol, betel- nut, cigarette consumption and health promoting behavior of industrial workers in Ghaziabad.

    PubMed

    Arora, Dimple; Marya, Charu Mohan; Menon, Ipseeta; Oberoi, Sukhvinder Singh; Dhingra, Chandan; Anand, Richa

    2015-01-01

    The work force in industries are at risk of developing unduly high rates of health and behaviour related problems including abuse of alcohol, betel nut and cigarette (alcohol, betel nut and cigarette consumption). This study describes the relationships between alcohol, betel nut and cigarette consumption and health promoting behaviour among industrial workers. A cross sectional survey was conducted on workers in various industries of Ghaziabad city with concerned authority permission. A sample size of 732 workers was calculated based on pilot study. Through Simple random sampling 732 workers in 20 to 50 years age group with informed consent were interviewed through structured, pretested, validated questionnaire in vernacular language by one calibrated investigator. Data on socio demography, alcohol, betel nut and cigarette consumption pattern and health behaviour were collected. The association between health promoting behaviour and alcohol, betel nut and cigarette consumption was analysed by Logistic regression and Chi-square test through SPSS 16 at p<0.05 and 95%CI as significant. Total prevalence of alcohol, betel nut and cigarette consumption in study population was 88%. The prevalence of individual alcohol, betel nut and cigarette consumption were 82%, 68% and 79% respectively. Combined alcohol, betel nut and cigarette prevalence in study population was 58%. Alcohol and cigarette users were significantly higher (p<0.001) in 30 to 40 years age group with lower level of education having poor attitude towards health promoting behaviour, poor oral hygiene practices and rare indulgence in regular physical exercise. This study stimulate further research on exploring methods to prevent initiation of health risk behaviour and promote healthy behaviour with cessation help for the current alcohol, betel nut and cigarette users.

  20. Nitrate regulates rhizobial and mycorrhizal symbiosis in common bean (Phaseolus vulgaris L.).

    PubMed

    Nanjareddy, Kalpana; Blanco, Lourdes; Arthikala, Manoj-Kumar; Affantrange, Xochitl Alvarado; Sánchez, Federico; Lara, Miguel

    2014-03-01

    Nitrogen-limited conditions are considered to be a prerequisite for legume-rhizobial symbiosis, but the effects of nitrate-rich conditions on symbiotic status remain poorly understood. We addressed this issue by examining rhizobial (Rhizobim tropici) and arbusclar mycorrhizal (Glomus intraradices) symbiosis in Phaseolus vulgaris L. cv. Negro Jamapa under nitrate pre-incubation and continuous nitrate conditions. Our results indicate that nitrate pre-incubation, independent of the concentration, did not affect nodule development. However, the continuous supply of nitrate at high concentrations impaired nodule maturation and nodule numbers. Low nitrate conditions, in addition to positively regulating nodule number, biomass, and nitrogenase activity, also extended the span of nitrogen-fixing activity. By contrast, for arbuscular mycorrhizae, continuous 10 and 50 mmol/L nitrate increased the percent root length colonization, concomitantly reduced arbuscule size, and enhanced ammonia transport without affecting phosphate transport. Therefore, in this manuscript, we have proposed the importance of nitrate as a positive regulator in promoting both rhizobial and mycorrhizal symbiosis in the common bean. © 2014 Institute of Botany, Chinese Academy of Sciences.

  1. Forests trapped in nitrogen limitation--an ecological market perspective on ectomycorrhizal symbiosis.

    PubMed

    Franklin, Oskar; Näsholm, Torgny; Högberg, Peter; Högberg, Mona N

    2014-07-01

    Ectomycorrhizal symbiosis is omnipresent in boreal forests, where it is assumed to benefit plant growth. However, experiments show inconsistent benefits for plants and volatility of individual partnerships, which calls for a re-evaluation of the presumed role of this symbiosis. We reconcile these inconsistencies by developing a model that demonstrates how mycorrhizal networking and market mechanisms shape the strategies of individual plants and fungi to promote symbiotic stability at the ecosystem level. The model predicts that plants switch abruptly from a mixed strategy with both mycorrhizal and nonmycorrhizal roots to a purely mycorrhizal strategy as soil nitrogen availability declines, in agreement with the frequency distribution of ectomycorrhizal colonization intensity across a wide-ranging data set. In line with observations in field-scale isotope labeling experiments, the model explains why ectomycorrhizal symbiosis does not alleviate plant nitrogen limitation. Instead, market mechanisms may generate self-stabilization of the mycorrhizal strategy via nitrogen depletion feedback, even if plant growth is ultimately reduced. We suggest that this feedback mechanism maintains the strong nitrogen limitation ubiquitous in boreal forests. The mechanism may also have the capacity to eliminate or even reverse the expected positive effect of rising CO2 on tree growth in strongly nitrogen-limited boreal forests.

  2. Forests trapped in nitrogen limitation – an ecological market perspective on ectomycorrhizal symbiosis

    PubMed Central

    Franklin, Oskar; Näsholm, Torgny; Högberg, Peter; Högberg, Mona N

    2014-01-01

    Ectomycorrhizal symbiosis is omnipresent in boreal forests, where it is assumed to benefit plant growth. However, experiments show inconsistent benefits for plants and volatility of individual partnerships, which calls for a re-evaluation of the presumed role of this symbiosis. We reconcile these inconsistencies by developing a model that demonstrates how mycorrhizal networking and market mechanisms shape the strategies of individual plants and fungi to promote symbiotic stability at the ecosystem level. The model predicts that plants switch abruptly from a mixed strategy with both mycorrhizal and nonmycorrhizal roots to a purely mycorrhizal strategy as soil nitrogen availability declines, in agreement with the frequency distribution of ectomycorrhizal colonization intensity across a wide-ranging data set. In line with observations in field-scale isotope labeling experiments, the model explains why ectomycorrhizal symbiosis does not alleviate plant nitrogen limitation. Instead, market mechanisms may generate self-stabilization of the mycorrhizal strategy via nitrogen depletion feedback, even if plant growth is ultimately reduced. We suggest that this feedback mechanism maintains the strong nitrogen limitation ubiquitous in boreal forests. The mechanism may also have the capacity to eliminate or even reverse the expected positive effect of rising CO2 on tree growth in strongly nitrogen-limited boreal forests. PMID:24824576

  3. Tobacco industry price-subsidizing promotions may overcome the downward pressure of higher prices on initiation of regular smoking.

    PubMed

    Pierce, John P; Gilmer, Todd P; Lee, Lora; Gilpin, Elizabeth A; de Beyer, Joy; Messer, Karen

    2005-10-01

    Real cigarette prices in the US increased from the early 1980s to early 1990s. Holding all else equal, adolescent initiation of regular smoking should have declined during this period. Using national population-based surveys (n = 336 343) conducted in the 1990s, we present trends (early 1960s to mid-1990s) in the initiation of regular smoking among 14-17-year-old adolescents and 18-21-year-old young adults. We also present trends in consumer-price-index-adjusted cigarette price and tobacco-industry expenditures for price-subsidizing promotions. We relate price and price-subsidizing tobacco industry expenditures to trends in initiation in the two age groups, using autoregressive integrated moving average models (ARIMA). From the model results, we conclude that price-subsidizing promotions may provide the tobacco industry with an effective way to segment the market. That is, they effectively offer lower prices to population subgroups that are more price-sensitive (e.g. young smokers not yet addicted), countering the depressing effect of general price increases on smoking. Thus, we find that the relationship of cigarette price to smoking behavior is more complex than previously described.

  4. Arbuscular mycorrhizal symbiosis influences strigolactone production under salinity and alleviates salt stress in lettuce plants.

    PubMed

    Aroca, Ricardo; Ruiz-Lozano, Juan Manuel; Zamarreño, Angel María; Paz, José Antonio; García-Mina, José María; Pozo, María José; López-Ráez, Juan Antonio

    2013-01-01

    Arbuscular mycorrhizal (AM) symbiosis can alleviate salt stress in plants. However the intimate mechanisms involved, as well as the effect of salinity on the production of signalling molecules associated to the host plant-AM fungus interaction remains largely unknown. In the present work, we have investigated the effects of salinity on lettuce plant performance and production of strigolactones, and assessed its influence on mycorrhizal root colonization. Three different salt concentrations were applied to mycorrhizal and non-mycorrhizal plants, and their effects, over time, analyzed. Plant biomass, stomatal conductance, efficiency of photosystem II, as well as ABA content and strigolactone production were assessed. The expression of ABA biosynthesis genes was also analyzed. AM plants showed improved growth rates and a better performance of physiological parameters such as stomatal conductance and efficiency of photosystem II than non-mycorrhizal plants under salt stress since very early stages - 3 weeks - of plant colonization. Moreover, ABA levels were lower in those plants, suggesting that they were less stressed than non-colonized plants. On the other hand, we show that both AM symbiosis and salinity influence strigolactone production, although in a different way in AM and non-AM plants. The results suggest that AM symbiosis alleviates salt stress by altering the hormonal profiles and affecting plant physiology in the host plant. Moreover, a correlation between strigolactone production, ABA content, AM root colonization and salinity level is shown. We propose here that under these unfavourable conditions, plants increase strigolactone production in order to promote symbiosis establishment to cope with salt stress.

  5. BEOS-A new approach to promote and organize industrial ISS utilization

    NASA Astrophysics Data System (ADS)

    Luttmann, Helmut; Buchholz, Henning; Bratke, Burkhard; Hueser, Detlev; Dittus, Hansjörg

    2000-01-01

    In order to develop and to market innovative services and products for the operation of the ISS and its utilization, three players have teamed up together and established an entity called BEOS (Bremen Engineering Operations Science). The team is made up of DaimlerChrysler Aerospace, OHB-System and ZARM, the Center of Applied Space Technology and Microgravity at the University of Bremen. It is the aim of BEOS to represent a competent industrial interface to potential ISS users from the space and non-space industries. In this effort BEOS is supporting and supplementing the activities of the space agencies, especially in the field of industrial and/or commercial ISS utilization. With this approach BEOS is creating new business opportunities not only for its team members but also for its customers from industry. Besides the fostering of industrial research in space, nontechnical fields of space utilization like entertainment, advertisement, education and space travel represent further key sectors for the marketing efforts of BEOS. .

  6. Promoter Screening from Bacillus subtilis in Various Conditions Hunting for Synthetic Biology and Industrial Applications.

    PubMed

    Song, Yafeng; Nikoloff, Jonas M; Fu, Gang; Chen, Jingqi; Li, Qinggang; Xie, Nengzhong; Zheng, Ping; Sun, Jibin; Zhang, Dawei

    2016-01-01

    The use of Bacillus subtilis in synthetic biology and metabolic engineering is highly desirable to take advantage of the unique metabolic pathways present in this organism. To do this, an evaluation of B. subtilis' intrinsic biological parts is required to determine the best strategies to accurately regulate metabolic circuits and expression of target proteins. The strengths of promoter candidates were evaluated by measuring relative fluorescence units of a green fluorescent protein reporter, integrated into B. subtilis' chromosome. A total of 84 predicted promoter sequences located upstream of different classes of proteins including heat shock proteins, cell-envelope proteins, and proteins resistant against toxic metals (based on similarity) and other kinds of genes were tested. The expression levels measured ranged from 0.0023 to 4.53-fold of the activity of the well-characterized strong promoter P43. No significant shifts were observed when strains, carrying different promoter candidates, were cultured at high temperature or in media with ethanol, but some strains showed increased activity when cultured under high osmotic pressure. Randomly selected promoter candidates were tested and found to activate transcription of thermostable β-galactosidase (bgaB) at a similar level, implying the ability of these sequences to function as promoter elements in multiple genetic contexts. In addition, selected promoters elevated the final production of both cytoplasmic bgaB and secreted protein α-amylase to about fourfold and twofold, respectively. The generated data allows a deeper understanding of B. subtilis' metabolism and will facilitate future work to develop this organism for synthetic biology.

  7. Promoter Screening from Bacillus subtilis in Various Conditions Hunting for Synthetic Biology and Industrial Applications

    PubMed Central

    Fu, Gang; Chen, Jingqi; Li, Qinggang; Xie, Nengzhong; Zheng, Ping; Sun, Jibin; Zhang, Dawei

    2016-01-01

    The use of Bacillus subtilis in synthetic biology and metabolic engineering is highly desirable to take advantage of the unique metabolic pathways present in this organism. To do this, an evaluation of B. subtilis’ intrinsic biological parts is required to determine the best strategies to accurately regulate metabolic circuits and expression of target proteins. The strengths of promoter candidates were evaluated by measuring relative fluorescence units of a green fluorescent protein reporter, integrated into B. subtilis’ chromosome. A total of 84 predicted promoter sequences located upstream of different classes of proteins including heat shock proteins, cell-envelope proteins, and proteins resistant against toxic metals (based on similarity) and other kinds of genes were tested. The expression levels measured ranged from 0.0023 to 4.53-fold of the activity of the well-characterized strong promoter P43. No significant shifts were observed when strains, carrying different promoter candidates, were cultured at high temperature or in media with ethanol, but some strains showed increased activity when cultured under high osmotic pressure. Randomly selected promoter candidates were tested and found to activate transcription of thermostable β-galactosidase (bgaB) at a similar level, implying the ability of these sequences to function as promoter elements in multiple genetic contexts. In addition, selected promoters elevated the final production of both cytoplasmic bgaB and secreted protein α-amylase to about fourfold and twofold, respectively. The generated data allows a deeper understanding of B. subtilis’ metabolism and will facilitate future work to develop this organism for synthetic biology. PMID:27380260

  8. Brassinosteroids Regulate Root Growth, Development, and Symbiosis.

    PubMed

    Wei, Zhuoyun; Li, Jia

    2016-01-04

    Brassinosteroids (BRs) are natural plant hormones critical for growth and development. BR deficient or signaling mutants show significantly shortened root phenotypes. However, for a long time, it was thought that these phenotypes were solely caused by reduced cell elongation in the mutant roots. Functions of BRs in regulating root development have been largely neglected. Nonetheless, recent detailed analyses, revealed that BRs are not only involved in root cell elongation but are also involved in many aspects of root development, such as maintenance of meristem size, root hair formation, lateral root initiation, gravitropic response, mycorrhiza formation, and nodulation in legume species. In this review, current findings on the functions of BRs in mediating root growth, development, and symbiosis are discussed.

  9. Symbiosis and the origin of eukaryotic motility

    NASA Technical Reports Server (NTRS)

    Margulis, L.; Hinkle, G.

    1991-01-01

    Ongoing work to test the hypothesis of the origin of eukaryotic cell organelles by microbial symbioses is discussed. Because of the widespread acceptance of the serial endosymbiotic theory (SET) of the origin of plastids and mitochondria, the idea of the symbiotic origin of the centrioles and axonemes for spirochete bacteria motility symbiosis was tested. Intracellular microtubular systems are purported to derive from symbiotic associations between ancestral eukaryotic cells and motile bacteria. Four lines of approach to this problem are being pursued: (1) cloning the gene of a tubulin-like protein discovered in Spirocheata bajacaliforniesis; (2) seeking axoneme proteins in spirochets by antibody cross-reaction; (3) attempting to cultivate larger, free-living spirochetes; and (4) studying in detail spirochetes (e.g., Cristispira) symbiotic with marine animals. Other aspects of the investigation are presented.

  10. Symbiosis-inspired approaches to antibiotic discovery.

    PubMed

    Adnani, Navid; Rajski, Scott R; Bugni, Tim S

    2017-07-06

    Covering: 2010 up to 2017Life on Earth is characterized by a remarkable abundance of symbiotic and highly refined relationships among life forms. Defined as any kind of close, long-term association between two organisms, symbioses can be mutualistic, commensalistic or parasitic. Historically speaking, selective pressures have shaped symbioses in which one organism (typically a bacterium or fungus) generates bioactive small molecules that impact the host (and possibly other symbionts); the symbiosis is driven fundamentally by the genetic machineries available to the small molecule producer. The human microbiome is now integral to the most recent chapter in animal-microbe symbiosis studies and plant-microbe symbioses have significantly advanced our understanding of natural products biosynthesis; this also is the case for studies of fungal-microbe symbioses. However, much less is known about microbe-microbe systems involving interspecies interactions. Microbe-derived small molecules (i.e. antibiotics and quorum sensing molecules, etc.) have been shown to regulate transcription in microbes within the same environmental niche, suggesting interspecies interactions whereas, intraspecies interactions, such as those that exploit autoinducing small molecules, also modulate gene expression based on environmental cues. We, and others, contend that symbioses provide almost unlimited opportunities for the discovery of new bioactive compounds whose activities and applications have been evolutionarily optimized. Particularly intriguing is the possibility that environmental effectors can guide laboratory expression of secondary metabolites from "orphan", or silent, biosynthetic gene clusters (BGCs). Notably, many of the studies summarized here result from advances in "omics" technologies and highlight how symbioses have given rise to new anti-bacterial and antifungal natural products now being discovered.

  11. Advancing the health care supply chain and promoting leadership through strategic partnerships with industry.

    PubMed

    Motiwala, Sanober S; McLaughlin, Joan E; King, John; Hodgson, Brent; Hamilton, Michael

    2008-01-01

    While supply chain partnerships are common in the private industry, they are unique in health care. This article looks at the novel partnership between St. Michael's Hospital and Baxter Canada. By sharing information and working together, these organizations evaluated and tackled service disruptions caused by backorders. Their formal collaboration has resulted in a streamlined backorder management process, and more importantly, better and timelier patient care.

  12. Tax and Fiscal Policies for Promotion of Industrial EnergyEfficiency: A Survey of International Experience

    SciTech Connect

    Price, Lynn; Galitsky, Christina; Sinton, Jonathan; Worrell,Ernst; Graus, Wina

    2005-09-15

    The Energy Foundation's China Sustainable Energy Program (CSEP) has undertaken a major project investigating fiscal and tax policy options for stimulating energy efficiency and renewable energy development in China. This report, which is part of the sectoral sub-project studies on energy efficiency in industry, surveys international experience with tax and fiscal policies directed toward increasing investments in energy efficiency in the industrial sector. The report begins with an overview of tax and fiscal policies, including descriptions and evaluations of programs that use energy or energy-related carbon dioxide (CO2) taxes, pollution levies, public benefit charges, grants or subsidies, subsidized audits, loans, tax relief for specific technologies, and tax relief as part of an energy or greenhouse gas (GHG) emission tax or agreement scheme. Following the discussion of these individual policies, the report reviews experience with integrated programs found in two countries as well as with GHG emissions trading programs. The report concludes with a discussion of the best practices related to international experience with tax and fiscal policies to encourage investment in energy efficiency in industry.

  13. Computer symbiosis-emergence of symbiotic behavior through evolution

    NASA Astrophysics Data System (ADS)

    Ikegami, Takashi; Kaneko, Kunihiko

    1990-06-01

    Symbiosis is cooperation between distinct species. It is one of the most effective evolutionary processes, but its dynamics are not well understood as yet. A simple model of symbiosis is introduced, in which we consider interactions between hosts and parasites and also mutations of hosts and parasites. The interactions and mutations form a dynamical system on the populations of hosts and parasites. It is found that a symbiotic state emerges for a suitable range of mutation rates. The symbiotic state is not static, but dynamically oscillates. Harmful parasites violating symbiosis appear periodically, but are rapidly extinguished by hosts and other parasites, and the symbiotic state is recovered. The relation between these phenomena and “TIT for TAT” strategy to maintain symbiosis is discussed.

  14. Layers of Symbiosis - Visualizing the Termite Hindgut Microbial Community

    PubMed Central

    Leadbetter, Jared

    2007-01-01

    Jared Leadbetter takes us for a nature walk through the diversity of life resident in the termite hindgut - a microenvironment containing 250 different species found nowhere else on Earth. Jared reveals that the symbiosis exhibited by this system is multi-layered and involves not only a relationship between the termite and its gut inhabitants, but also involves a complex web of symbiosis among the gut microbes themselves. PMID:18979002

  15. Study of cnidarian-algal symbiosis in the "omics" age.

    PubMed

    Meyer, Eli; Weis, Virginia M

    2012-08-01

    The symbiotic associations between cnidarians and dinoflagellate algae (Symbiodinium) support productive and diverse ecosystems in coral reefs. Many aspects of this association, including the mechanistic basis of host-symbiont recognition and metabolic interaction, remain poorly understood. The first completed genome sequence for a symbiotic anthozoan is now available (the coral Acropora digitifera), and extensive expressed sequence tag resources are available for a variety of other symbiotic corals and anemones. These resources make it possible to profile gene expression, protein abundance, and protein localization associated with the symbiotic state. Here we review the history of "omics" studies of cnidarian-algal symbiosis and the current availability of sequence resources for corals and anemones, identifying genes putatively involved in symbiosis across 10 anthozoan species. The public availability of candidate symbiosis-associated genes leaves the field of cnidarian-algal symbiosis poised for in-depth comparative studies of sequence diversity and gene expression and for targeted functional studies of genes associated with symbiosis. Reviewing the progress to date suggests directions for future investigations of cnidarian-algal symbiosis that include (i) sequencing of Symbiodinium, (ii) proteomic analysis of the symbiosome membrane complex, (iii) glycomic analysis of Symbiodinium cell surfaces, and (iv) expression profiling of the gastrodermal cells hosting Symbiodinium.

  16. NIN Is Involved in the Regulation of Arbuscular Mycorrhizal Symbiosis.

    PubMed

    Guillotin, Bruno; Couzigou, Jean-Malo; Combier, Jean-Philippe

    2016-01-01

    Arbuscular mycorrhizal (AM) symbiosis is an intimate and ancient symbiosis found between most of terrestrial plants and fungi from the Glomeromycota family. Later during evolution, the establishment of the nodulation between legume plants and soil bacteria known as rhizobia, involved several genes of the signaling pathway previously implicated for AM symbiosis. For the past years, the identification of the genes belonging to this Common Symbiotic Signaling Pathway have been mostly done on nodulation. Among the different genes already well identified as required for nodulation, we focused our attention on the involvement of Nodule Inception (NIN) in AM symbiosis. We show here that NIN expression is induced during AM symbiosis, and that the Medicago truncatula nin mutant is less colonized than the wild-type M. truncatula strain. Moreover, nin mutant displays a defect in the ability to be infected by the fungus Rhizophagus irregularis. This work brings a new evidence of the common genes involved in overlapping signaling pathways of both nodulation and in AM symbiosis.

  17. NIN Is Involved in the Regulation of Arbuscular Mycorrhizal Symbiosis

    PubMed Central

    Guillotin, Bruno; Couzigou, Jean-Malo; Combier, Jean-Philippe

    2016-01-01

    Arbuscular mycorrhizal (AM) symbiosis is an intimate and ancient symbiosis found between most of terrestrial plants and fungi from the Glomeromycota family. Later during evolution, the establishment of the nodulation between legume plants and soil bacteria known as rhizobia, involved several genes of the signaling pathway previously implicated for AM symbiosis. For the past years, the identification of the genes belonging to this Common Symbiotic Signaling Pathway have been mostly done on nodulation. Among the different genes already well identified as required for nodulation, we focused our attention on the involvement of Nodule Inception (NIN) in AM symbiosis. We show here that NIN expression is induced during AM symbiosis, and that the Medicago truncatula nin mutant is less colonized than the wild-type M. truncatula strain. Moreover, nin mutant displays a defect in the ability to be infected by the fungus Rhizophagus irregularis. This work brings a new evidence of the common genes involved in overlapping signaling pathways of both nodulation and in AM symbiosis. PMID:27899928

  18. [From health promotion to return to work--report from industrial medicine practice].

    PubMed

    Glomm, D

    2012-01-01

    Company doctors can assume an important moderator function in company health management because they know both the individual employee with his or her abilities and functional disorders as well as the individual workplace and its organizational framework conditions. Moreover, they have access to population groups who would not as a rule make use of health care services. In the framework of industrial medicine preventive examinations, consultations and workplace inspections, they can identify a need for rehabilitation at an early stage, can support applications for services and return to work, and thus contribute to greater sustainability. © Georg Thieme Verlag KG Stuttgart · New York.

  19. Dealing with an innovative industry: a look at flavored cigarettes promoted by mainstream brands.

    PubMed

    Lewis, M Jane; Wackowski, Olivia

    2006-02-01

    Product and marketing innovation is key to the tobacco industry's success. One recent innovation was the development and marketing of flavored cigarettes as line extensions of 3 popular brands (Camel, Salem, and Kool). These products have distinctive blends and marketing as well as innovative packaging and have raised concerns in the public health community that they are targeted at youths. Several policy initiatives have aimed at banning or limiting these types of products on that basis. We describe examples of the products and their marketing and discuss their potential implications (including increased smoking experimentation, consumption, and "someday smoking"), as well as their potential impact on young adults.

  20. Development of an Integrative Program of Nanosafety: Promote the Coordination Between Industries and Risk Assessor

    NASA Astrophysics Data System (ADS)

    Emond, Claude; Kouassi, Serge; Schuster, Frédéric

    2013-04-01

    Nanomaterials are widely present in many industrial sectors (e.g., chemical, biomedical, environment), and their application is expected to significantly expand in the coming years. However, nanomaterial use raises many questions about the potential risks to human health and the environment and, more specifically, to occupational health. The available literature supports the ability of the lung, gastrointestinal tract, and skin to act as significant barriers against systemic exposure to many nanomaterials. However, because a potential risk issue exists about the toxicity of nanomaterials to the biological material, tools need to be developed for improving the risk management of the regulators. The goal is to develop a tool that examines the current knowledge base regarding the health risks posed by engineered nanoparticles to improve nanotechnology safety prior to the marketing phase. The approach proposed during this work was to establish a safety assessment constructed on a decision-control pathway regarding nanomaterial production and consumer's product to integrate different aspects. These aspects include: (1) primarily research and identification of the nanomaterial base of physicochemical properties, toxicity, and application; (2) the occupational exposure risk during the manufacturing process; (3) and the engineered nanomaterial upon the consumer product. This approach provides important parameters to reduce the uncertainty related to the production of nanomaterials prior their commercialization, reduce the reluctance from the industry, and provide a certification tool of sanitary control for the regulators. This work provides a better understanding of a critical issue of nanomaterials and consumer safety.

  1. Asian success stories in promoting energy efficiency in industry and building

    SciTech Connect

    Yang, Ming

    1996-12-31

    This article describes the program of the International Institute for Energy Conservation (IIEC), which has offices in Washington, Bangkok, Santiago, and London, in addition to staff in a number of other countries. The mission of this private organization is to promote the efficient use of energy as a tool for sustainable development by supporting the development of policies, technologies, and practices. Its focus is on energy efficiency, transportation systems, and renewable energy sources. Examples of specific program activities in Thailand, China, Philippines, Malaysia, Indonesia and Singapore are discussed.

  2. Stars and symbiosis: microRNA- and microRNA*-mediated transcript cleavage involved in arbuscular mycorrhizal symbiosis.

    PubMed

    Devers, Emanuel A; Branscheid, Anja; May, Patrick; Krajinski, Franziska

    2011-08-01

    The majority of plants are able to form the arbuscular mycorrhizal (AM) symbiosis in association with AM fungi. During symbiosis development, plant cells undergo a complex reprogramming resulting in profound morphological and physiological changes. MicroRNAs (miRNAs) are important components of the regulatory network of plant cells. To unravel the impact of miRNAs and miRNA-mediated mRNA cleavage on root cell reprogramming during AM symbiosis, we carried out high-throughput (Illumina) sequencing of small RNAs and degradome tags of Medicago truncatula roots. This led to the annotation of 243 novel miRNAs. An increased accumulation of several novel and conserved miRNAs in mycorrhizal roots suggest a role of these miRNAs during AM symbiosis. The degradome analysis led to the identification of 185 root transcripts as mature miRNA and also miRNA*-mediated mRNA cleavage targets. Several of the identified miRNA targets are known to be involved in root symbioses. In summary, the increased accumulation of specific miRNAs and the miRNA-mediated cleavage of symbiosis-relevant genes indicate that miRNAs are an important part of the regulatory network leading to symbiosis development.

  3. The university-promoted patent at the crossroads of the research results and immediate industrial use.

    PubMed

    Doddoli, R

    2007-02-01

    The departments, indeed the laboratories of the public research institutions, no longer are satisfied with displaying a certain number of annual scientific publications meant to highlight their expertise and know-how. In effect, for some years now, a new trend has been in vogue: stimulated by all the national and international public bodies, they are calling increasingly on the "patent pending" solution to make optimum use of the results of specific researches on the one hand and, on the other hand, to assert their excellence vis-à-vis the Ministry of Research of their country which is supposed to finance them. However, caught up in the euphoria of the research results, and lost in their formulae and practices, these researchers lose sight of the basis for a patent and its real reason for being (patent charter). A patent necessarily must be of service to the community, that is to say that essentially it must contribute to the improvement of the quality of life of the population. To achieve this goal, going through certain stages is a must, namely that to start with a patent must be absolutely profitable to industry in order that, subsequently, it be consistent with its being of service to the community. In this context, its validity is set at 10 years renewable for another 10 years based on specific parameters as stipulated by the national and international patent institutions, indeed by the EPO (European Patent Office) the headquarters of which is in Munich. Its use by industry ensures proceeds for 10, even 20 years and must represent the material fruit of the applicant's effort. Beyond this period, the patent becomes public and therefore available to everyone. But the crucial problem is this: when can a patent really be used and how to do so as best as possible to guarantee profits for both parties involved and thus justify its reason for being? The purpose of this work thus is to incite university researchers to think about the real usefulness of a patent on

  4. Feeding horses with industrially manufactured pellets with fungal spores to promote nematode integrated control.

    PubMed

    Hernández, José Ángel; Arroyo, Fabián Leonardo; Suárez, José; Cazapal-Monteiro, Cristiana Filipa; Romasanta, Ángel; López-Arellano, María Eugenia; Pedreira, José; de Carvalho, Luis Manuel Madeira; Sánchez-Andrade, Rita; Arias, María Sol; de Gives, Pedro Mendoza; Paz-Silva, Adolfo

    2016-10-15

    The usefulness of pellets industrially manufactured with spores of parasiticide fungi as a contribution to integrated nematode control was assessed in grazing horses throughout sixteen months. Two groups of 7 Pura Raza Galega autochthonous horses (G-T and G-P) were dewormed pour-on (1mg Ivermectin/kg bw) at the beginning of the trial, and other group (G-C) remained untreated. The G-P was provided daily with commercial pellets to which was added a mixture of fungal spores during the industrial manufacturing (2×10(6) spores of Mucor circinelloides and same dose of Duddingtonia flagrans/kg), and G-T and G-C received pellets without spores. The efficacy of the parasiticidal strategy was assessed by estimating the reduction in the faecal egg counts (FECR) and in the number of horses shedding eggs in the faeces (PHR), and also the egg reappearance periods (ERP). Blood analyses were performed to identify the changes in the red and white cell patterns. To ascertain if horses developed an IgG humoral response against the fungi, antigenic products collected from M. circinelloides and D. flagrans were exposed to the horse sera by using an ELISA. The faecal elimination of eggs of Parascaris equorum and strongyles ceased 2 weeks after treatment in G-T and G-P, thus the values of FECR and PHR were 100%. No P. equorum-eggs were detected later, and the strongyle egg reappearance period was 28 weeks in G-P, and 8 weeks in G-T. Strongyle egg-output values remained lower than 300 eggs per gram of faeces in the G-P, whereas numbers between 330 and 772 in G-C and G-T were recorded. Normal values for the erythrocytes, haemoglobin and haematocrit in horses consuming pellets with spores were recorded, and lower than normal in the other groups. Sensitization of horses to the fungal species was disproven. It is concluded that feeding horses with pellets industrially manufactured with fungal spores represents a very useful tool to implement an integrated control of helminths affecting

  5. Promoting pollution prevention through community-industry dialogues: the good neighbor model in Minnesota.

    PubMed

    Murdock, Barbara Scott; Sexton, Ken

    2002-05-15

    This article examines five attempts by communities to promote pollution prevention through direct negotiations with local manufacturing plants. These projects were Good Neighbor Dialogues spearheaded by Citizens for a Better Environment-Minnesota, an environmental advocacy organization. Three community-company partnerships (a container plant, a foundry, and a cabinet manufacturer) were successful and two (a munitions plant and a petroleum refinery) were not. Successful dialogues all shared certain characteristics: the company was open to negotiating with the community; there was an effective "champion" within the company; a skilled, independent facilitator served as moderator; community participants received independent technical assistance; and both the company and community understood the value of cooperative environmental decision making. Results suggest that Good Neighbor Dialogues can, under the right settings and circumstances, be an effective mechanism for building social capital by fostering greater understanding and trust between companies and communities. They offer the prospect of community-company partnerships that promote pollution prevention and other environmental improvements, while at the same time reinforcing and amplifying traditional pollution control strategies.

  6. Promoting reproductive health practices among working adolescents and young adults (industrial workers). RAS/88/P11.

    PubMed

    1999-06-01

    In Cambodia, Care (Deutschland), through the Cambodia Health Education Development (CHED) and the Reproductive Health Association of Cambodia, is working towards the promotion of reproductive health (RH) practices among working adolescents and young adults. The project seeks to reach a minimum target group of 10,000 out-of-school, single, working adolescents and young adults aged 12-29 years, and at least 50 trained RH providers and educators in selected project sites. It also aims to provide specialist RH services to at least 200 single adolescents and young adults per month and per newly operational RH facility in project areas; and to build the capacity of at least two partner nongovernmental organizations in adolescent RH services. As its two-part strategy, the project is sharing information, education, and communication (IEC) expertise and using CHED as an informal IEC clearing house. The main activities of the project are outlined.

  7. Use of municipal incinerator bottom ash as sintering promoter in industrial ceramics.

    PubMed

    Barbieri, L; Corradi, A; Lancellotti, I; Manfredini, T

    2002-01-01

    The use of glassy frits obtained from municipal incinerator bottom ash and glass cullet, as sintering promoters in the production process of porcelainized stoneware, was investigated. The emphasis was on studying the similarities and differences with respect to the standard body. The characterization involved the application of several techniques: chemical analysis, X-ray powder diffraction, linear shrinkage during firing, water absorption, bending strength and spot resistance test. The results show that, the addition of these glassy frits in the body improve the characteristics of water absorption and spot resistance which is related to the absence of surface porosity originated by the glassy phase. Moreover, addition of glassy frits to the porcelanized stoneware body does not change significantly its bending strength. In the firing conditions used there is a slight worsening in the tiles planarity, while there is a significant modification of the color, which becomes darker with respect to the base body.

  8. Immunosuppression during Rhizobium-legume symbiosis.

    PubMed

    Luo, Li; Lu, Dawei

    2014-01-01

    Rhizobium infects host legumes to elicit new plant organs, nodules where dinitrogen is fixed as ammonia that can be directly utilized by plants. The nodulation factor (NF) produced by Rhizobium is one of the determinant signals for rhizobial infection and nodule development. Recently, it was found to suppress the innate immunity on host and nonhost plants as well as its analogs, chitins. Therefore, NF can be recognized as a microbe/pathogen-associated molecular pattern (M/PAMP) like chitin to induce the M/PAMP triggered susceptibility (M/PTS) of host plants to rhizobia. Whether the NF signaling pathway is directly associated with the innate immunity is not clear till now. In fact, other MAMPs such as lipopolysaccharide (LPS), exopolysaccharide (EPS) and cyclic-β-glucan, together with type III secretion system (T3SS) effectors are also required for rhizobial infection or survival in leguminous nodule cells. Interestingly, most of them play similarly negative roles in the innate immunity of host plants, though their signaling is not completely elucidated. Taken together, we believe that the local immunosuppression on host plants induced by Rhizobium is essential for the establishment of their symbiosis.

  9. Phylogeny, genomics, and symbiosis of Photobacterium.

    PubMed

    Urbanczyk, Henryk; Ast, Jennifer C; Dunlap, Paul V

    2011-03-01

    Photobacterium comprises several species in Vibrionaceae, a large family of Gram-negative, facultatively aerobic, bacteria that commonly associate with marine animals. Members of the genus are widely distributed in the marine environment and occur in seawater, surfaces, and intestines of marine animals, marine sediments and saline lake water, and light organs of fish. Seven Photobacterium species are luminous via the activity of the lux genes, luxCDABEG. Much recent progress has been made on the phylogeny, genomics, and symbiosis of Photobacterium. Phylogenetic analysis demonstrates a robust separation between Photobacterium and its close relatives, Aliivibrio and Vibrio, and reveals the presence of two well-supported clades. Clade 1 contains luminous and symbiotic species and one species with no luminous members, and Clade 2 contains mostly nonluminous species. The genomes of Photobacterium are similar in size, structure, and organization to other members of Vibrionaceae, with two chromosomes of unequal size and multiple rrn operons. Many species of marine fish form bioluminescent symbioses with three Photobacterium species: Photobacterium kishitanii, Photobacterium leiognathi, and Photobacterium mandapamensis. These associations are highly, but not strictly species specific, and they do not exhibit symbiont-host codivergence. Environmental congruence instead of host selection might explain the patterns of symbiont-host affiliation observed from nature.

  10. Bacterial communities associated with the lichen symbiosis.

    PubMed

    Bates, Scott T; Cropsey, Garrett W G; Caporaso, J Gregory; Knight, Rob; Fierer, Noah

    2011-02-01

    Lichens are commonly described as a mutualistic symbiosis between fungi and "algae" (Chlorophyta or Cyanobacteria); however, they also have internal bacterial communities. Recent research suggests that lichen-associated microbes are an integral component of lichen thalli and that the classical view of this symbiotic relationship should be expanded to include bacteria. However, we still have a limited understanding of the phylogenetic structure of these communities and their variability across lichen species. To address these knowledge gaps, we used bar-coded pyrosequencing to survey the bacterial communities associated with lichens. Bacterial sequences obtained from four lichen species at multiple locations on rock outcrops suggested that each lichen species harbored a distinct community and that all communities were dominated by Alphaproteobacteria. Across all samples, we recovered numerous bacterial phylotypes that were closely related to sequences isolated from lichens in prior investigations, including those from a lichen-associated Rhizobiales lineage (LAR1; putative N(2) fixers). LAR1-related phylotypes were relatively abundant and were found in all four lichen species, and many sequences closely related to other known N(2) fixers (e.g., Azospirillum, Bradyrhizobium, and Frankia) were recovered. Our findings confirm the presence of highly structured bacterial communities within lichens and provide additional evidence that these bacteria may serve distinct functional roles within lichen symbioses.

  11. Promoting emerging energy-efficiency technologies and practices by utilities in a restructured energy industry: A report from California

    SciTech Connect

    Vine, Edward L.

    2000-07-01

    The potential energy savings from emerging technologies (i.e., those technologies emerging from research and development) represent a significant resource to California and the US This paper describes how California's investor-owned utilities (IOUs) have been promoting emerging technologies over the last three years to increase energy efficiency in the buildings sector. During these years, the IOUs have experienced significant changes in their regulatory environment as part of the restructuring of the energy industry in California. These regulatory changes have impacted the way emerging technologies are treated by the regulatory community and the IOUs. After reviewing these changes, the paper concludes by discussing potential opportunities to improve the market penetration of emerging technologies.

  12. Six-year cost trends at PPG industries paralleling the introduction of health promotion programs directed at cardiovascular disease prevention.

    PubMed

    Goetzel, Ron Z; Kowlessar, Niranjana M; Henke, Rachel; Benevent, Richele; Tabrizi, Maryam; Colombi, Alberto M

    2013-05-01

    Over the past several years, PPG Industries (PPG) implemented worksite health promotion programs aimed at improving employees' health and reducing overall medical costs as well as those specific to cardiovascular disease. Using medical claims data, we examined trends in these costs among PPG employees for a 6-year period, from 2005 to 2010. Overall medical costs remained relatively flat, increasing by 1.2% compounded annually, unadjusted for inflation, while inflation-adjusted costs declined by 2.9%. Comparing worksites rated "high-high" on both program implementation and leadership support with worksites scoring highly on one or none of those dimensions, the "high-high" group experienced a decreasing cost trend, whereas the "other" group showed an increase. The analysis suggests that PPG's efforts to reconfigure and intensify its wellness program offerings may have resulted lower health care cost trends.

  13. Promoting female condoms in the sex industry in 4 towns of Southern China: context matters.

    PubMed

    Nie, Li; Liao, Susu; Weeks, Margaret R; Wang, Yanhong; Jiang, Jingmei; Zhang, Qingning; Zhou, Yuejiao; He, Bin; Li, Jianghong; Dunn, Jennifer

    2013-03-01

    The female condom (FC) is an effective tool for dual protection, but it remains underused. Individual and contextual reasons need to be explored. The aim of this study was to compare individual and contextual characteristics of FC multitime users, 1-time users, and nonusers among women in the sex industry of 4 study sites in China. A standardized 1-year FC intervention along with male condoms was implemented through outreach to sex establishments. Three serial cross-sectional surveys were conducted at baseline and after each of two 6-month intervention phases. A total of 445, 437, and 290 eligible women were interviewed at 3 cross-sectional surveys, respectively. At the first and second postintervention surveys, 83.3% and 81.7% of women reported knowing about FC, and 28.8% and 36.6% had used FC at least once. Women who used FC multiple times reported less unprotected sex than nonusers in the last 30 days (3.0% vs. 17.2% at first and 3.2% vs. 16.8% at second postintervention survey, P < 0.01). Polytomous logistic regression showed that both 1-time and multitime users were more likely to come from one particular site (approximately 3 times more than the reference site). Higher intervention scores (adjusted odds ratio, 1.8-4.0) and working in boarding houses (adjusted odds ratio, 3.4) were associated with FC use. Adding FC into male-condom-only intervention may reduce unprotected sex among women in sex establishments in rural and small urban areas of China. Adoption of FC may be related not only to intervention exposure but also to contextual factors associated with study site and type of sex establishments.

  14. Promoting Female Condoms in the Sex Industry in Four Towns of Southern China: Context Matters

    PubMed Central

    Nie, Li; Liao, Susu; Weeks, Margaret R.; Wang, Yanhong; Jiang, Jingmei; Zhang, Qingning; Zhou, Yuejiao; He, Bin; Li, Jianghong; Dunn, Jennifer

    2012-01-01

    Background The female condom (FC) is an effective tool for dual protection, but it remains underused. Individual as well as contextual reasons need to be explored. Objective To compare individual and contextual characteristics of FC multi-time users, one-time users and non-users among women in the sex industry of four study sites in China. Methods A standardized one-year FC intervention along with male condoms was implemented through outreach to sex establishments. Three serial cross-sectional surveys were conducted at baseline and after each of two six-month intervention phases. Results A total of 445, 437 and 290 eligible women were interviewed at three cross-sectional surveys, respectively. At the first and second post-intervention surveys, 83.3% and 81.7% of women reported knowing about FC, and 28.8% and 36.6% had used FC at least once. Women who used FC multiple times reported less unprotected sex than non-users in the last 30 days (3.0% vs. 17.2% at first and 3.2% vs. 16.8% at second post-intervention survey, p<0.01). Polytomous logistic regression showed that both one-time and multi-time users were more likely to come from one particular site (about 3 times more than the reference site). Higher intervention scores (adjusted OR 1.8–4.0) and working in boarding houses (adjusted OR 3.4) were associated with FC use. Conclusions Adding FC into male-condom-only intervention may reduce unprotected sex among women in sex establishments in rural and small urban areas of China. Adoption of FC may be related not only to intervention exposure, but also to contextual factors associated with study site and type of sex establishments. PMID:23403607

  15. Phytoremediation of heavy and transition metals aided by legume-rhizobia symbiosis.

    PubMed

    Hao, X; Taghavi, S; Xie, P; Orbach, M J; Alwathnani, H A; Rensing, C; Wei, G

    2014-01-01

    Legumes are important for nitrogen cycling in the environment and agriculture due to the ability of nitrogen fixation by rhizobia. In this review, we introduce an important and potential role of legume-rhizobia symbiosis in aiding phytoremediation of some metal contaminated soils as various legumes have been found to be the dominant plant species in metal contaminated areas. Resistant rhizobia used for phytoremediation could act on metals directly by chelation, precipitation, transformation, biosorption and accumulation. Moreover, the plant growth promoting (PGP) traits of rhizobia including nitrogen fixation, phosphorus solubilization, phytohormone synthesis, siderophore release, and production of ACC deaminase and the volatile compounds of acetoin and 2, 3-butanediol may facilitate legume growth while lessening metal toxicity. The benefits of using legumes inoculated with naturally resistant rhizobia or recombinant rhizobia with enhanced resistance, as well as co-inoculation with other plant growth promoting bacteria (PGPB) are discussed. However, the legume-rhizobia symbiosis appears to be sensitive to metals, and the effect of metal toxicity on the interaction between legumes and rhizobia is not clear. Therefore, to obtain the maximum benefits from legumes assisted by rhizobia for phytoremediation of metals, it is critical to have a good understanding of interactions between PGP traits, the symbiotic plant-rhizobia relationship and metals.

  16. DELLA proteins regulate arbuscule formation in arbuscular mycorrhizal symbiosis.

    PubMed

    Floss, Daniela S; Levy, Julien G; Lévesque-Tremblay, Véronique; Pumplin, Nathan; Harrison, Maria J

    2013-12-17

    Most flowering plants are able to form endosymbioses with arbuscular mycorrhizal fungi. In this mutualistic association, the fungus colonizes the root cortex and establishes elaborately branched hyphae, called arbuscules, within the cortical cells. Arbuscule development requires the cellular reorganization of both symbionts, and the resulting symbiotic interface functions in nutrient exchange. A plant symbiosis signaling pathway controls the development of the symbiosis. Several components of the pathway have been identified, but transcriptional regulators that control downstream pathways for arbuscule formation are still unknown. Here we show that DELLA proteins, which are repressors of gibberellic acid (GA) signaling and function at the nexus of several signaling pathways, are required for arbuscule formation. Arbuscule formation is severely impaired in a Medicago truncatula Mtdella1/Mtdella2 double mutant; GA treatment of wild-type roots phenocopies the della double mutant, and a dominant DELLA protein (della1-Δ18) enables arbuscule formation in the presence of GA. Ectopic expression of della1-Δ18 suggests that DELLA activity in the vascular tissue and endodermis is sufficient to enable arbuscule formation in the inner cortical cells. In addition, expression of della1-Δ18 restores arbuscule formation in the symbiosis signaling pathway mutant cyclops/ipd3, indicating an intersection between DELLA and symbiosis signaling for arbuscule formation. GA signaling also influences arbuscule formation in monocots, and a Green Revolution wheat variety carrying dominant DELLA alleles shows enhanced colonization but a limited growth response to arbuscular mycorrhizal symbiosis.

  17. DELLA proteins regulate arbuscule formation in arbuscular mycorrhizal symbiosis

    PubMed Central

    Floss, Daniela S.; Levy, Julien G.; Lévesque-Tremblay, Véronique; Pumplin, Nathan; Harrison, Maria J.

    2013-01-01

    Most flowering plants are able to form endosymbioses with arbuscular mycorrhizal fungi. In this mutualistic association, the fungus colonizes the root cortex and establishes elaborately branched hyphae, called arbuscules, within the cortical cells. Arbuscule development requires the cellular reorganization of both symbionts, and the resulting symbiotic interface functions in nutrient exchange. A plant symbiosis signaling pathway controls the development of the symbiosis. Several components of the pathway have been identified, but transcriptional regulators that control downstream pathways for arbuscule formation are still unknown. Here we show that DELLA proteins, which are repressors of gibberellic acid (GA) signaling and function at the nexus of several signaling pathways, are required for arbuscule formation. Arbuscule formation is severely impaired in a Medicago truncatula Mtdella1/Mtdella2 double mutant; GA treatment of wild-type roots phenocopies the della double mutant, and a dominant DELLA protein (della1-Δ18) enables arbuscule formation in the presence of GA. Ectopic expression of della1-Δ18 suggests that DELLA activity in the vascular tissue and endodermis is sufficient to enable arbuscule formation in the inner cortical cells. In addition, expression of della1-Δ18 restores arbuscule formation in the symbiosis signaling pathway mutant cyclops/ipd3, indicating an intersection between DELLA and symbiosis signaling for arbuscule formation. GA signaling also influences arbuscule formation in monocots, and a Green Revolution wheat variety carrying dominant DELLA alleles shows enhanced colonization but a limited growth response to arbuscular mycorrhizal symbiosis. PMID:24297892

  18. Symbiosis-induced adaptation to oxidative stress.

    PubMed

    Richier, Sophie; Furla, Paola; Plantivaux, Amandine; Merle, Pierre-Laurent; Allemand, Denis

    2005-01-01

    Cnidarians in symbiosis with photosynthetic protists must withstand daily hyperoxic/anoxic transitions within their host cells. Comparative studies between symbiotic (Anemonia viridis) and non-symbiotic (Actinia schmidti) sea anemones show striking differences in their response to oxidative stress. First, the basal expression of SOD is very different. Symbiotic animal cells have a higher isoform diversity (number and classes) and a higher activity than the non-symbiotic cells. Second, the symbiotic animal cells of A. viridis also maintain unaltered basal values for cellular damage when exposed to experimental hyperoxia (100% O(2)) or to experimental thermal stress (elevated temperature +7 degrees C above ambient). Under such conditions, A. schmidti modifies its SOD activity significantly. Electrophoretic patterns diversify, global activities diminish and cell damage biomarkers increase. These data suggest symbiotic cells adapt to stress while non-symbiotic cells remain acutely sensitive. In addition to being toxic, high O(2) partial pressure (P(O(2))) may also constitute a preconditioning step for symbiotic animal cells, leading to an adaptation to the hyperoxic condition and, thus, to oxidative stress. Furthermore, in aposymbiotic animal cells of A. viridis, repression of some animal SOD isoforms is observed. Meanwhile, in cultured symbionts, new activity bands are induced, suggesting that the host might protect its zooxanthellae in hospite. Similar results have been observed in other symbiotic organisms, such as the sea anemone Aiptasia pulchella and the scleractinian coral Stylophora pistillata. Molecular or physical interactions between the two symbiotic partners may explain such variations in SOD activity and might confer oxidative stress tolerance to the animal host.

  19. Ocean acidification alters fish–jellyfish symbiosis

    PubMed Central

    Nagelkerken, Ivan; Pitt, Kylie A.; Rutte, Melchior D.; Geertsma, Robbert C.

    2016-01-01

    Symbiotic relationships are common in nature, and are important for individual fitness and sustaining species populations. Global change is rapidly altering environmental conditions, but, with the exception of coral–microalgae interactions, we know little of how this will affect symbiotic relationships. We here test how the effects of ocean acidification, from rising anthropogenic CO2 emissions, may alter symbiotic interactions between juvenile fish and their jellyfish hosts. Fishes treated with elevated seawater CO2 concentrations, as forecast for the end of the century on a business-as-usual greenhouse gas emission scenario, were negatively affected in their behaviour. The total time that fish (yellowtail scad) spent close to their jellyfish host in a choice arena where they could see and smell their host was approximately three times shorter under future compared with ambient CO2 conditions. Likewise, the mean number of attempts to associate with jellyfish was almost three times lower in CO2-treated compared with control fish, while only 63% (high CO2) versus 86% (control) of all individuals tested initiated an association at all. By contrast, none of three fish species tested were attracted solely to jellyfish olfactory cues under present-day CO2 conditions, suggesting that the altered fish–jellyfish association is not driven by negative effects of ocean acidification on olfaction. Because shelter is not widely available in the open water column and larvae of many (and often commercially important) pelagic species associate with jellyfish for protection against predators, modification of the fish–jellyfish symbiosis might lead to higher mortality and alter species population dynamics, and potentially have flow-on effects for their fisheries. PMID:27358374

  20. Ocean acidification alters fish-jellyfish symbiosis.

    PubMed

    Nagelkerken, Ivan; Pitt, Kylie A; Rutte, Melchior D; Geertsma, Robbert C

    2016-06-29

    Symbiotic relationships are common in nature, and are important for individual fitness and sustaining species populations. Global change is rapidly altering environmental conditions, but, with the exception of coral-microalgae interactions, we know little of how this will affect symbiotic relationships. We here test how the effects of ocean acidification, from rising anthropogenic CO2 emissions, may alter symbiotic interactions between juvenile fish and their jellyfish hosts. Fishes treated with elevated seawater CO2 concentrations, as forecast for the end of the century on a business-as-usual greenhouse gas emission scenario, were negatively affected in their behaviour. The total time that fish (yellowtail scad) spent close to their jellyfish host in a choice arena where they could see and smell their host was approximately three times shorter under future compared with ambient CO2 conditions. Likewise, the mean number of attempts to associate with jellyfish was almost three times lower in CO2-treated compared with control fish, while only 63% (high CO2) versus 86% (control) of all individuals tested initiated an association at all. By contrast, none of three fish species tested were attracted solely to jellyfish olfactory cues under present-day CO2 conditions, suggesting that the altered fish-jellyfish association is not driven by negative effects of ocean acidification on olfaction. Because shelter is not widely available in the open water column and larvae of many (and often commercially important) pelagic species associate with jellyfish for protection against predators, modification of the fish-jellyfish symbiosis might lead to higher mortality and alter species population dynamics, and potentially have flow-on effects for their fisheries.

  1. An antimicrobial peptide essential for bacterial survival in the nitrogen-fixing symbiosis.

    PubMed

    Kim, Minsoo; Chen, Yuhui; Xi, Jiejun; Waters, Christopher; Chen, Rujin; Wang, Dong

    2015-12-08

    In the nitrogen-fixing symbiosis between legume hosts and rhizobia, the bacteria are engulfed by a plant cell membrane to become intracellular organelles. In the model legume Medicago truncatula, internalization and differentiation of Sinorhizobium (also known as Ensifer) meliloti is a prerequisite for nitrogen fixation. The host mechanisms that ensure the long-term survival of differentiating intracellular bacteria (bacteroids) in this unusual association are unclear. The M. truncatula defective nitrogen fixation4 (dnf4) mutant is unable to form a productive symbiosis, even though late symbiotic marker genes are expressed in mutant nodules. We discovered that in the dnf4 mutant, bacteroids can apparently differentiate, but they fail to persist within host cells in the process. We found that the DNF4 gene encodes NCR211, a member of the family of nodule-specific cysteine-rich (NCR) peptides. The phenotype of dnf4 suggests that NCR211 acts to promote the intracellular survival of differentiating bacteroids. The greatest expression of DNF4 was observed in the nodule interzone II-III, where bacteroids undergo differentiation. A translational fusion of DNF4 with GFP localizes to the peribacteroid space, and synthetic NCR211 prevents free-living S. meliloti from forming colonies, in contrast to mock controls, suggesting that DNF4 may interact with bacteroids directly or indirectly for its function. Our findings indicate that a successful symbiosis requires host effectors that not only induce bacterial differentiation, but also that maintain intracellular bacteroids during the host-symbiont interaction. The discovery of NCR211 peptides that maintain bacterial survival inside host cells has important implications for improving legume crops.

  2. An antimicrobial peptide essential for bacterial survival in the nitrogen-fixing symbiosis

    PubMed Central

    Kim, Minsoo; Chen, Yuhui; Xi, Jiejun; Waters, Christopher; Chen, Rujin; Wang, Dong

    2015-01-01

    In the nitrogen-fixing symbiosis between legume hosts and rhizobia, the bacteria are engulfed by a plant cell membrane to become intracellular organelles. In the model legume Medicago truncatula, internalization and differentiation of Sinorhizobium (also known as Ensifer) meliloti is a prerequisite for nitrogen fixation. The host mechanisms that ensure the long-term survival of differentiating intracellular bacteria (bacteroids) in this unusual association are unclear. The M. truncatula defective nitrogen fixation4 (dnf4) mutant is unable to form a productive symbiosis, even though late symbiotic marker genes are expressed in mutant nodules. We discovered that in the dnf4 mutant, bacteroids can apparently differentiate, but they fail to persist within host cells in the process. We found that the DNF4 gene encodes NCR211, a member of the family of nodule-specific cysteine-rich (NCR) peptides. The phenotype of dnf4 suggests that NCR211 acts to promote the intracellular survival of differentiating bacteroids. The greatest expression of DNF4 was observed in the nodule interzone II-III, where bacteroids undergo differentiation. A translational fusion of DNF4 with GFP localizes to the peribacteroid space, and synthetic NCR211 prevents free-living S. meliloti from forming colonies, in contrast to mock controls, suggesting that DNF4 may interact with bacteroids directly or indirectly for its function. Our findings indicate that a successful symbiosis requires host effectors that not only induce bacterial differentiation, but also that maintain intracellular bacteroids during the host–symbiont interaction. The discovery of NCR211 peptides that maintain bacterial survival inside host cells has important implications for improving legume crops. PMID:26598690

  3. On Human Symbiosis and the Vicissitudes of Individuation. Infantile Psychosis, Volume 1.

    ERIC Educational Resources Information Center

    Mahler, Margaret S.

    The concepts of symbiosis and separation-individuation are explained, and the symbiosis theory of infantile psychosis is presented. Diagnostic considerations and clinical cases of child psychosis are reviewed; prototypes of mother-child interaction are described; and therapy is discussed. A summary of the symbiosis theory and a bibliography of…

  4. Strigolactones in the Rhizobium-legume symbiosis: Stimulatory effect on bacterial surface motility and down-regulation of their levels in nodulated plants.

    PubMed

    Peláez-Vico, María A; Bernabéu-Roda, Lydia; Kohlen, Wouter; Soto, María J; López-Ráez, Juan A

    2016-04-01

    Strigolactones (SLs) are multifunctional molecules acting as modulators of plant responses under nutrient deficient conditions. One of the roles of SLs is to promote beneficial association with arbuscular mycorrhizal (AM) fungi belowground under such stress conditions, mainly phosphorus shortage. Recently, a role of SLs in the Rhizobium-legume symbiosis has been also described. While SLs' function in AM symbiosis is well established, their role in the Rhizobium-legume interaction is still emerging. Recently, SLs have been suggested to stimulate surface motility of rhizobia, opening the possibility that they could also act as molecular cues. The possible effect of SLs in the motility in the alfalfa symbiont Sinorhizobium meliloti was investigated, showing that the synthetic SL analogue GR24 stimulates swarming motility in S. meliloti in a dose-dependent manner. On the other hand, it is known that SL production is regulated by nutrient deficient conditions and by AM symbiosis. Using the model alfalfa-S. meliloti, the impact of phosphorus and nitrogen deficiency, as well as of nodulation on SL production was also assessed. The results showed that phosphorus starvation promoted SL biosynthesis, which was abolished by nitrogen deficiency. In addition, a negative effect of nodulation on SL levels was detected, suggesting a conserved mechanism of SL regulation upon symbiosis establishment.

  5. [LEGUME-RHIZOBIUM SYMBIOSIS PROTEOMICS: ACHIEVEMENTS AND PERSPECTIVES].

    PubMed

    Kondratiuk, Iu Iu; Mamenko, P M; Kots, S Ya

    2015-01-01

    The present review contains results of proteomic researches of legume-rhizobium symbiosis. The technical difficulties associated with the methods of obtaining protein extracts from symbiotic structures and ways of overcoming them were discussed. The changes of protein synthesis under formation and functioning of symbiotic structures were shown. Special attention has been given to the importance of proteomic studies of plant-microbe structures in the formation of adaptation strategies under adverse environmental conditions. The technical and conceptual perspectives of legume-rhizobium symbiosis proteomics were shown.

  6. Evolving together: the biology of symbiosis, part 1

    PubMed Central

    2000-01-01

    Symbioses, prolonged associations between organisms often widely separated phylogenetically, are more common in biology than we once thought and have been neglected as a phenomenon worthy of study on its own merits. Extending along a dynamic continuum from antagonistic to cooperative and often involving elements of both antagonism and mutualism, symbioses involve pathogens, commensals, and mutualists interacting in myriad ways over the evolutionary history of the involved “partners.” In this first of 2 parts, some remarkable examples of symbiosis will be explored, from the coral-algal symbiosis and nitrogen fixation to the great diversity of dietary specializations enabled by the gastrointestinal microbiota of animals. PMID:16389385

  7. Symbiosis between microorganisms from kombucha and kefir: Potential significance to the enhancement of kombucha function.

    PubMed

    Yang, Zhiwei; Zhou, Feng; Ji, Baoping; Li, Bo; Luo, Yangchao; Yang, Li; Li, Tao

    2010-01-01

    Gluconacetobacter sp. A4 (G. sp. A4), which had strong ability to produce d-saccharic acid 1, 4 lactone (DSL), was the key functional bacteria isolated from the kombucha preserved. This paper investigated the interaction between G. sp. A4 and ten different strains of lactic acid bacteria (LAB) obtained from kefir. The result suggested that the LAB promoted DSL production of G. sp. A4 to different extents, ranging from 4.86% to 86.70%. Symbiosis between G. sp. A4 and LAB was studied. LAB's metabolites, xylitol, and acetic acid, were utilized by G. sp. A4, and it promoted the growth of G. sp. A4 and yield of DSL. Therefore, in developing starter cultures for kombucha fermentation process, a mixed flora of LAB and G. sp. A4 would be the optimal combination.

  8. Current knowledge on the environmental fate, potential impact, and management of growth-promoting steroids used in the US beef cattle industry

    USDA-ARS?s Scientific Manuscript database

    Growth promoting steroids and steroid-like compounds (GPSC) used by the US beef cattle industry are potential contaminants to water resources. Manure generated in concentrated animal feeding operations contains GPSCs that may enter the environment. Several studies have focused on off-site impacts of...

  9. The receptor kinase CERK1 has dual functions in symbiosis and immunity signalling.

    PubMed

    Zhang, Xiaowei; Dong, Wentao; Sun, Jongho; Feng, Feng; Deng, Yiwen; He, Zuhua; Oldroyd, Giles E D; Wang, Ertao

    2015-01-01

    The establishment of symbiotic interactions between mycorrhizal fungi, rhizobial bacteria and their legume hosts involves a common symbiosis signalling pathway. This signalling pathway is activated by Nod factors produced by rhizobia and these are recognised by the Nod factor receptors NFR1/LYK3 and NFR5/NFP. Mycorrhizal fungi produce lipochitooligosaccharides (LCOs) similar to Nod factors, as well as short-chain chitin oligomers (CO4/5), implying commonalities in signalling during mycorrhizal and rhizobial associations. Here we show that NFR1/LYK3, but not NFR5/NFP, is required for the establishment of the mycorrhizal interaction in legumes. NFR1/LYK3 is necessary for the recognition of mycorrhizal fungi and the activation of the symbiosis signalling pathway leading to induction of calcium oscillations and gene expression. Chitin oligosaccharides also act as microbe associated molecular patterns that promote plant immunity via similar LysM receptor-like kinases. CERK1 in rice has the highest homology to NFR1 and we show that this gene is also necessary for the establishment of the mycorrhizal interaction as well as for resistance to the rice blast fungus. Our results demonstrate that NFR1/LYK3/OsCERK1 represents a common receptor for chitooligosaccharide-based signals produced by mycorrhizal fungi, rhizobial bacteria (in legumes) and fungal pathogens. It would appear that mycorrhizal recognition has been conserved in multiple receptors across plant species, but additional diversification in certain plant species has defined other signals that this class of receptors can perceive.

  10. A novel plant-fungus symbiosis benefits the host without forming mycorrhizal structures.

    PubMed

    Kariman, Khalil; Barker, Susan J; Jost, Ricarda; Finnegan, Patrick M; Tibbett, Mark

    2014-03-01

    • Most terrestrial plants form mutually beneficial symbioses with specific soil-borne fungi known as mycorrhiza. In a typical mycorrhizal association, fungal hyphae colonize plant roots, explore the soil beyond the rhizosphere and provide host plants with nutrients that might be chemically or physically inaccessible to root systems. • Here, we combined nutritional, radioisotopic ((33)P) and genetic approaches to describe a plant growth promoting symbiosis between the basidiomycete fungus Austroboletus occidentalis and jarrah (Eucalyptus marginata), which has quite different characteristics. • We show that the fungal partner does not colonize plant roots; hyphae are localized to the rhizosphere soil and vicinity and consequently do not transfer nutrients located beyond the rhizosphere. Transcript profiling of two high-affinity phosphate (Pi) transporter genes (EmPHT1;1 and EmPHT1;2) and hyphal-mediated (33)Pi uptake suggest that the Pi uptake shifts from an epidermal to a hyphal pathway in ectomycorrhizal plants (Scleroderma sp.), similar to arbuscular mycorrhizal symbioses, whereas A. occidentalis benefits its host indirectly. The enhanced rhizosphere carboxylates are linked to growth and nutritional benefits in the novel symbiosis. • This work is a starting point for detailed mechanistic studies on other basidiomycete-woody plant relationships, where a continuum between heterotrophic rhizosphere fungi and plant beneficial symbioses is likely to exist.

  11. Sea turtle symbiosis facilitates social monogamy in oceanic crabs via refuge size

    PubMed Central

    Gil, Michael A.

    2016-01-01

    The capacity for resource monopolization by individuals often dictates the size and composition of animal groups, and ultimately, the adoption of mating strategies. For refuge-dwelling animals, the ability (or inability) of individuals to monopolize refuges should depend on the relative size of the refuge. In theory, groups should be larger and more inclusive when refuges are large, and smaller and more exclusive when refuges are small, regardless of refuge type. We test this prediction by comparing the size and composition of groups of oceanic crabs (Planes minutus) living on plastic flotsam and loggerhead sea turtles. We found that (i) surface area of refuges (barnacle colonies on flotsam and supracaudal space on turtles) is a better predictor of crab number than total surface area and (ii) flotsam and turtles with similar refuge surface area host a similar number (1–2) and composition (adult male–female pairs) of crabs. These results indicate that group size and composition of refuge-dwelling animals are modulated by refuge size and the capacity for refuge monopolization. Moreover, these results suggest that sea turtle symbiosis facilitates social monogamy in oceanic crabs, providing insights into how symbiosis can promote specific mating strategies. PMID:27651538

  12. Genome of an arbuscular mycorrhizal fungus provides insight into the oldest plant symbiosis

    PubMed Central

    Tisserant, Emilie; Malbreil, Mathilde; Kuo, Alan; Kohler, Annegret; Symeonidi, Aikaterini; Balestrini, Raffaella; Charron, Philippe; Duensing, Nina; Frei dit Frey, Nicolas; Gianinazzi-Pearson, Vivienne; Gilbert, Luz B.; Handa, Yoshihiro; Herr, Joshua R.; Hijri, Mohamed; Koul, Raman; Kawaguchi, Masayoshi; Krajinski, Franziska; Lammers, Peter J.; Masclaux, Frederic G.; Murat, Claude; Morin, Emmanuelle; Ndikumana, Steve; Pagni, Marco; Petitpierre, Denis; Requena, Natalia; Rosikiewicz, Pawel; Riley, Rohan; Saito, Katsuharu; San Clemente, Hélène; Shapiro, Harris; van Tuinen, Diederik; Bécard, Guillaume; Bonfante, Paola; Paszkowski, Uta; Shachar-Hill, Yair Y.; Tuskan, Gerald A.; Young, J. Peter W.; Sanders, Ian R.; Henrissat, Bernard; Rensing, Stefan A.; Grigoriev, Igor V.; Corradi, Nicolas; Roux, Christophe; Martin, Francis

    2013-01-01

    The mutualistic symbiosis involving Glomeromycota, a distinctive phylum of early diverging Fungi, is widely hypothesized to have promoted the evolution of land plants during the middle Paleozoic. These arbuscular mycorrhizal fungi (AMF) perform vital functions in the phosphorus cycle that are fundamental to sustainable crop plant productivity. The unusual biological features of AMF have long fascinated evolutionary biologists. The coenocytic hyphae host a community of hundreds of nuclei and reproduce clonally through large multinucleated spores. It has been suggested that the AMF maintain a stable assemblage of several different genomes during the life cycle, but this genomic organization has been questioned. Here we introduce the 153-Mb haploid genome of Rhizophagus irregularis and its repertoire of 28,232 genes. The observed low level of genome polymorphism (0.43 SNP per kb) is not consistent with the occurrence of multiple, highly diverged genomes. The expansion of mating-related genes suggests the existence of cryptic sex-related processes. A comparison of gene categories confirms that R. irregularis is close to the Mucoromycotina. The AMF obligate biotrophy is not explained by genome erosion or any related loss of metabolic complexity in central metabolism, but is marked by a lack of genes encoding plant cell wall-degrading enzymes and of genes involved in toxin and thiamine synthesis. A battery of mycorrhiza-induced secreted proteins is expressed in symbiotic tissues. The present comprehensive repertoire of R. irregularis genes provides a basis for future research on symbiosis-related mechanisms in Glomeromycota. PMID:24277808

  13. Toward a better understanding of the mechanisms of symbiosis: a comprehensive proteome map of a nascent insect symbiont.

    PubMed

    Renoz, François; Champagne, Antoine; Degand, Hervé; Faber, Anne-Marie; Morsomme, Pierre; Foray, Vincent; Hance, Thierry

    2017-01-01

    Symbiotic bacteria are common in insects and can affect various aspects of their hosts' biology. Although the effects of insect symbionts have been clarified for various insect symbiosis models, due to the difficulty of cultivating them in vitro, there is still limited knowledge available on the molecular features that drive symbiosis. Serratia symbiotica is one of the most common symbionts found in aphids. The recent findings of free-living strains that are considered as nascent partners of aphids provide the opportunity to examine the molecular mechanisms that a symbiont can deploy at the early stages of the symbiosis (i.e., symbiotic factors). In this work, a proteomic approach was used to establish a comprehensive proteome map of the free-living S. symbiotica strain CWBI-2.3(T). Most of the 720 proteins identified are related to housekeeping or primary metabolism. Of these, 76 were identified as candidate proteins possibly promoting host colonization. Our results provide strong evidence that S. symbiotica CWBI-2.3(T) is well-armed for invading insect host tissues, and suggest that certain molecular features usually harbored by pathogenic bacteria are no longer present. This comprehensive proteome map provides a series of candidate genes for further studies to understand the molecular cross-talk between insects and symbiotic bacteria.

  14. Toward a better understanding of the mechanisms of symbiosis: a comprehensive proteome map of a nascent insect symbiont

    PubMed Central

    Champagne, Antoine; Degand, Hervé; Faber, Anne-Marie; Morsomme, Pierre; Foray, Vincent; Hance, Thierry

    2017-01-01

    Symbiotic bacteria are common in insects and can affect various aspects of their hosts’ biology. Although the effects of insect symbionts have been clarified for various insect symbiosis models, due to the difficulty of cultivating them in vitro, there is still limited knowledge available on the molecular features that drive symbiosis. Serratia symbiotica is one of the most common symbionts found in aphids. The recent findings of free-living strains that are considered as nascent partners of aphids provide the opportunity to examine the molecular mechanisms that a symbiont can deploy at the early stages of the symbiosis (i.e., symbiotic factors). In this work, a proteomic approach was used to establish a comprehensive proteome map of the free-living S. symbiotica strain CWBI-2.3T. Most of the 720 proteins identified are related to housekeeping or primary metabolism. Of these, 76 were identified as candidate proteins possibly promoting host colonization. Our results provide strong evidence that S. symbiotica CWBI-2.3T is well-armed for invading insect host tissues, and suggest that certain molecular features usually harbored by pathogenic bacteria are no longer present. This comprehensive proteome map provides a series of candidate genes for further studies to understand the molecular cross-talk between insects and symbiotic bacteria. PMID:28503376

  15. Signaling events during initiation of arbuscular mycorrhizal symbiosis.

    PubMed

    Schmitz, Alexa M; Harrison, Maria J

    2014-03-01

    Under nutrient-limiting conditions, plants will enter into symbiosis with arbuscular mycorrhizal (AM) fungi for the enhancement of mineral nutrient acquisition from the surrounding soil. AM fungi live in close, intracellular association with plant roots where they transfer phosphate and nitrogen to the plant in exchange for carbon. They are obligate fungi, relying on their host as their only carbon source. Much has been discovered in the last decade concerning the signaling events during initiation of the AM symbiosis, including the identification of signaling molecules generated by both partners. This signaling occurs through symbiosis-specific gene products in the host plant, which are indispensable for normal AM development. At the same time, plants have adapted complex mechanisms for avoiding infection by pathogenic fungi, including an innate immune response to general microbial molecules, such as chitin present in fungal cell walls. How it is that AM fungal colonization is maintained without eliciting a defensive response from the host is still uncertain. In this review, we present a summary of the molecular signals and their elicited responses during initiation of the AM symbiosis, including plant immune responses and their suppression.

  16. Transgenerational effects of plant sex and arbuscular mycorrhizal symbiosis.

    PubMed

    Varga, Sandra; Vega-Frutis, Rocío; Kytöviita, Minna-Maarit

    2013-08-01

    In gynodioecious plants, females are predicted to produce more and/or better offspring than hermaphrodites in order to be maintained in the same population. In the field, the roots of both sexes are usually colonized by arbuscular mycorrhizal (AM) fungi. Transgenerational effects of mycorrhizal symbiosis are largely unknown, although theoretically expected. We examined the maternal and paternal effects of AM fungal symbiosis and host sex on seed production and posterior seedling performance in Geranium sylvaticum, a gynodioecious plant. We hand-pollinated cloned females and hermaphrodites in symbiosis with AM fungi or in nonmycorrhizal conditions and measured seed number and mass, and seedling survival and growth in a glasshouse experiment. Females produced more seeds than hermaphrodites, but the seeds did not germinate, survive or grow better. Mycorrhizal plants were larger, but did not produce more seeds than nonmycorrhizal plants. Transgenerational parental effects of AM fungi were verified in seedling performance. This is the first study to show transgenerational mycorrhiza-mediated parental effects in a gynodioecious species. Mycorrhizal symbiosis affects plant fitness mainly through female functions with enduring effects on the next generation.

  17. Evaluation of Project Symbiosis: An Interdisciplinary Science Education Project.

    ERIC Educational Resources Information Center

    Altschuld, James W.

    1993-01-01

    The goal of this report is to provide a summary of the evaluation of Project Symbiosis which focused on enhancing the teaching of science principles in high school agriculture courses. The project initially involved 15 teams of science and agriculture teachers and was characterized by an extensive evaluation component consisting of six formal…

  18. Bark Beetle-Fungal Symbiosis: Context Dependency in Complex Associations

    Treesearch

    Kier D. Klepzig; D.L. Six

    2004-01-01

    Recent thinking in symbiosis research has emphasized a holistic consideration of these complex interactions. Bark beetles and their associated microbes are one group which has previously not been addressed in this manner. We review the study of symbiotic interactions among bark beetles and microbes in light of this thinking. We describe the considerable progress...

  19. Reporters and Congressmen: Living in Symbiosis. Journalism Monographs No. 53.

    ERIC Educational Resources Information Center

    Miller, Susan Heilmann

    Although philosophers in the United States have advocated the concept of adversarity for the relationship between reporters and people in Congress, in actuality these two groups work together in symbiosis. This document reports on a study in which 190 reporters, members of Congress, and Congressional aides were interviewed regarding particular…

  20. Quorum sensing in the squid-Vibrio symbiosis.

    PubMed

    Verma, Subhash C; Miyashiro, Tim

    2013-08-07

    Quorum sensing is an intercellular form of communication that bacteria use to coordinate group behaviors such as biofilm formation and the production of antibiotics and virulence factors. The term quorum sensing was originally coined to describe the mechanism underlying the onset of luminescence production in cultures of the marine bacterium Vibrio fischeri. Luminescence and, more generally, quorum sensing are important for V. fischeri to form a mutualistic symbiosis with the Hawaiian bobtail squid, Euprymna scolopes. The symbiosis is established when V. fischeri cells migrate via flagella-based motility from the surrounding seawater into a specialized structure injuvenile squid called the light organ. The cells grow to high cell densities within the light organ where the infection persists over the lifetime of the animal. A hallmark of a successful symbiosis is the luminescence produced by V. fischeri that camouflages the squid at night by eliminating its shadow within the water column. While the regulatory networks governing quorum sensing are critical for properly regulating V. fischeri luminescence within the squid light organ, they also regulate luminescence-independent processes during symbiosis. In this review, we discuss the quorum-sensing network of V. fischeri and highlight its impact at various stages during host colonization.

  1. Identification of genes controlling development of arbuscules in AM symbiosis

    USDA-ARS?s Scientific Manuscript database

    Most vascular flowering plants have the capacity to form mutualistic symbioses with arbuscular mycorrhizal (AM) fungi. These associations develop in the roots where the fungus delivers phosphate to the root cortical cells and receives carbon from its plant host. During the symbiosis, the fungus prol...

  2. Polar localization of a symbiosis-specific phosphate transporter is mediated by a transient reorientation of secretion.

    PubMed

    Pumplin, Nathan; Zhang, Xinchun; Noar, Roslyn D; Harrison, Maria J

    2012-03-13

    The arbuscular mycorrhizal (AM) symbiosis, formed by land plants and AM fungi, evolved an estimated 400 million years ago and has been maintained in angiosperms, gymnosperms, pteridophytes, and some bryophytes as a strategy for enhancing phosphate acquisition. During AM symbiosis, the AM fungus colonizes the root cortical cells where it forms branched hyphae called arbuscules that function in nutrient exchange with the plant. Each arbuscule is enveloped in a plant membrane, the periarbuscular membrane, that contains a unique set of proteins including phosphate transporters such as Medicago truncatula MtPT4 [Javot et al., (2007) Proc Natl Acad Sci USA 104:1720-1725], which are essential for symbiotic phosphate transport. The periarbuscular membrane is physically continuous with the plasma membrane of the cortical cell, but MtPT4 and other periarbuscular membrane-resident proteins are located only in the domain around the arbuscule branches. Establishing the distinct protein composition of the periarbuscular membrane is critical for AM symbiosis, but currently the mechanism by which this composition is achieved is unknown. Here we investigate the targeting of MtPT4 to the periarbuscular membrane. By expressing MtPT4 and other plasma membrane proteins from promoters active at different phases of the symbiosis, we show that polar targeting of MtPT4 is mediated by precise temporal expression coupled with a transient reorientation of secretion and alterations in the protein cargo entering the secretory system of the colonized root cell. In addition, analysis of phosphate transporter mutants implicates the trans-Golgi network in phosphate transporter secretion.

  3. Symbiosis increases coral tolerance to ocean acidification

    NASA Astrophysics Data System (ADS)

    Ohki, S.; Irie, T.; Inoue, M.; Shinmen, K.; Kawahata, H.; Nakamura, T.; Kato, A.; Nojiri, Y.; Suzuki, A.; Sakai, K.; van Woesik, R.

    2013-04-01

    Increasing the acidity of ocean waters will directly threaten calcifying marine organisms such as reef-building scleractinian corals, and the myriad of species that rely on corals for protection and sustenance. Ocean pH has already decreased by around 0.1 pH units since the beginning of the industrial revolution, and is expected to decrease by another 0.2-0.4 pH units by 2100. This study mimicked the pre-industrial, present, and near-future levels of pCO2 using a precise control system (±5% pCO2), to assess the impact of ocean acidification on the calcification of recently-settled primary polyps of Acropora digitifera, both with and without symbionts, and adult fragments with symbionts. The increase in pCO2 of 100 μatm between the pre-industrial period and the present had more effect on the calcification rate of adult A. digitifera than the anticipated future increases of several hundreds of micro-atmospheres of pCO2. The primary polyps with symbionts showed higher calcification rates than primary polyps without symbionts, suggesting that (i) primary polyps housing symbionts are more tolerant to near-future ocean acidification than organisms without symbionts, and (ii) corals acquiring symbionts from the environment (i.e. broadcasting species) will be more vulnerable to ocean acidification than corals that maternally acquire symbionts.

  4. Personality psychology's comeback and its emerging symbiosis with social psychology.

    PubMed

    Swann, William B; Seyle, Conor

    2005-02-01

    Psychology's early allegiance to behaviorism and experimental methods led many to disparage personality approaches throughout much of last century. Doubts about personality psychology's viability culminated in Mischel's assertion that measures of personality account for modest amounts of variance in behavior. In the years immediately following this critique, interest in personality research waned and many psychology departments dropped their training programs in personality. Throughout the past two decades, however, personality psychology has enjoyed a resurgence. The authors discuss several possible explanations for personality's comeback and then describe the emergence of a promising symbiosis between personality psychology and its sister discipline, social psychology. The article concludes by noting that although this emerging symbiosis is likely to continue bearing considerable theoretical fruit, the traditional distinction between personal, situational, and interactional determinants of behavior continues to be useful within appropriate contexts.

  5. Contribution of the arbuscular mycorrhizal symbiosis to heavy metal phytoremediation.

    PubMed

    Göhre, Vera; Paszkowski, Uta

    2006-05-01

    High concentrations of heavy metals (HM) in the soil have detrimental effects on ecosystems and are a risk to human health as they can enter the food chain via agricultural products or contaminated drinking water. Phytoremediation, a sustainable and inexpensive technology based on the removal of pollutants from the environment by plants, is becoming an increasingly important objective in plant research. However, as phytoremediation is a slow process, improvement of efficiency and thus increased stabilization or removal of HMs from soils is an important goal. Arbuscular mycorrhizal (AM) fungi provide an attractive system to advance plant-based environmental clean-up. During symbiotic interaction the hyphal network functionally extends the root system of their hosts. Thus, plants in symbiosis with AM fungi have the potential to take up HM from an enlarged soil volume. In this review, we summarize current knowledge about the contribution of the AM symbiosis to phytoremediation of heavy metals.

  6. Establishment of coral-algal symbiosis requires attraction and selection.

    PubMed

    Yamashita, Hiroshi; Suzuki, Go; Kai, Sayaka; Hayashibara, Takeshi; Koike, Kazuhiko

    2014-01-01

    Coral reef ecosystems are based on coral-zooxanthellae symbiosis. During the initiation of symbiosis, majority of corals acquire their own zooxanthellae (specifically from the dinoflagellate genus Symbiodinium) from surrounding environments. The mechanisms underlying the initial establishment of symbiosis have attracted much interest, and numerous field and laboratory experiments have been conducted to elucidate this establishment. However, it is still unclear whether the host corals selectively or randomly acquire their symbionts from surrounding environments. To address this issue, we initially compared genetic compositions of Symbiodinium within naturally settled about 2-week-old Acropora coral juveniles (recruits) and those in the adjacent seawater as the potential symbiont source. We then performed infection tests using several types of Symbiodinium culture strains and apo-symbiotic (does not have Symbiodinium cells yet) Acropora coral larvae. Our field observations indicated apparent preference toward specific Symbiodinium genotypes (A1 and D1-4) within the recruits, despite a rich abundance of other Symbiodinium in the environmental population pool. Laboratory experiments were in accordance with this field observation: Symbiodinium strains of type A1 and D1-4 showed higher infection rates for Acropora larvae than other genotype strains, even when supplied at lower cell densities. Subsequent attraction tests revealed that three Symbiodinium strains were attracted toward Acropora larvae, and within them, only A1 and D1-4 strains were acquired by the larvae. Another three strains did not intrinsically approach to the larvae. These findings suggest the initial establishment of corals-Symbiodinium symbiosis is not random, and the infection mechanism appeared to comprise two steps: initial attraction step and subsequent selective uptake by the coral.

  7. The genome of Laccaria bicolor provides insights into mycorrhizal symbiosis

    SciTech Connect

    Martin, F.; Aerts, A.; Ahren, D.; Brun, A.; Danchin, E. G. J.; Duchaussoy, F.; Gibon, J.; Kohler, A.; Lindquist, E.; Peresa, V.; Salamov, A.; Shapiro, H. J.; Wuyts, J.; Blaudez, D.; Buee, M.; Brokstein, P.; Canback, B.; Cohen, D.; Courty, P. E.; Coutinho, P. M.; Delaruelle, C.; Detter, J. C.; Deveau, A.; DiFazio, S.; Duplessis, S.; Fraissinet-Tachet, L.; Lucic, E.; Frey-Klett, P.; Fourrey, C.; Feussner, I.; Gay, G.; Grimwood, J.; Hoegger, P. J.; Jain, P.; Kilaru, S.; Labbe, J.; Lin, Y. C.; Legue, V.; Le Tacon, F.; Marmeisse, R.; Melayah, D.; Montanini, B.; Muratet, M.; Nehls, U.; Niculita-Hirzel, H.; Secq, M. P. Oudot-Le; Peter, M.; Quesneville, H.; Rajashekar, B.; Reich, M.; Rouhier, N.; Schmutz, J.; Yin, T.; Chalot, M.; Henrissat, B.; Kues, U.; Lucas, S.; Van de Peer, Y.; Podila, G. K.; Polle, A.; Pukkila, P. J.; Richardson, P. M.; Rouze, P.; Sanders, I. R.; Stajich, J. E.; Tunlid, A.; Tuskan, G.; Grigoriev, I. V.

    2007-08-10

    Mycorrhizal symbioses the union of roots and soil fungi are universal in terrestrial ecosystems and may have been fundamental to land colonization by plants 1, 2. Boreal, temperate and montane forests all depend on ectomycorrhizae1. Identification of the primary factors that regulate symbiotic development and metabolic activity will therefore open the door to understanding the role of ectomycorrhizae in plant development and physiology, allowing the full ecological significance of this symbiosis to be explored. Here we report the genome sequence of the ectomycorrhizal basidiomycete Laccaria bicolor (Fig. 1) and highlight gene sets involved in rhizosphere colonization and symbiosis. This 65-megabase genome assembly contains 20,000 predicted protein-encoding genes and a very large number of transposons and repeated sequences. We detected unexpected genomic features, most notably a battery of effector-type small secreted proteins (SSPs) with unknown function, several of which are only expressed in symbiotic tissues. The most highly expressed SSP accumulates in the proliferating hyphae colonizing the host root. The ectomycorrhizae-specific SSPs probably have a decisive role in the establishment of the symbiosis. The unexpected observation that the genome of L. bicolor lacks carbohydrate-active enzymes involved in degradation of plant cell walls, but maintains the ability to degrade non-plant cell wall polysaccharides, reveals the dual saprotrophic and biotrophic lifestyle of the mycorrhizal fungus that enables it to grow within both soil and living plant roots. The predicted gene inventory of the L. bicolor genome, therefore, points to previously unknown mechanisms of symbiosis operating in biotrophic mycorrhizal fungi. The availability of this genome provides an unparalleled opportunity to develop a deeper understanding of the processes by which symbionts interact with plants within their ecosystem to perform vital functions in the carbon and nitrogen cycles that are

  8. The Food Industry and Self-Regulation: Standards to Promote Success and to Avoid Public Health Failures

    PubMed Central

    Sharma, Lisa L.; Teret, Stephen P.

    2010-01-01

    Threatened by possible government regulation and critical public opinion, industries often undertake self-regulatory actions, issue statements of concern for public welfare, and assert that self-regulation is sufficient to protect the public. The food industry has made highly visible pledges to curtail children's food marketing, sell fewer unhealthy products in schools, and label foods in responsible ways. Ceding regulation to industry carries opportunities but is highly risky. In some industries (e.g., tobacco), self-regulation has been an abject failure, but in others (e.g., forestry and marine fisheries), it has been more successful. We examined food industry self-regulation in the context of other self-regulatory successes and failures and defined 8 standards that should be met if self-regulation is to be effective. PMID:20019306

  9. Shoot- and root-borne cytokinin influences arbuscular mycorrhizal symbiosis.

    PubMed

    Cosme, Marco; Ramireddy, Eswarayya; Franken, Philipp; Schmülling, Thomas; Wurst, Susanne

    2016-10-01

    The arbuscular mycorrhizal (AM) symbiosis is functionally important for the nutrition and growth of most terrestrial plants. Nearly all phytohormones are employed by plants to regulate the symbiosis with AM fungi, but the regulatory role of cytokinin (CK) is not well understood. Here, we used transgenic tobacco (Nicotiana tabacum) with a root-specific or constitutive expression of CK-degrading CKX genes and the corresponding wild-type to investigate whether a lowered content of CK in roots or in both roots and shoots influences the interaction with the AM fungus Rhizophagus irregularis. Our data indicates that shoot CK has a positive impact on AM fungal development in roots and on the root transcript level of an AM-responsive phosphate transporter gene (NtPT4). A reduced CK content in roots caused shoot and root growth depression following AM colonization, while neither the uptake of phosphorus or nitrogen nor the root transcript levels of NtPT4 were significantly affected. This suggests that root CK may restrict the C availability from the roots to the fungus thus averting parasitism by AM fungi. Taken together, our study indicates that shoot- and root-borne CK have distinct roles in AM symbiosis. We propose a model illustrating how plants may employ CK to regulate nutrient exchange with the ubiquitous AM fungi.

  10. Coral Reef Genomics: Developing tools for functional genomics ofcoral symbiosis

    SciTech Connect

    Schwarz, Jodi; Brokstein, Peter; Manohar, Chitra; Coffroth, MaryAlice; Szmant, Alina; Medina, Monica

    2005-03-01

    Symbioses between cnidarians and dinoflagellates in the genus Symbiodinium are widespread in the marine environment. The importance of this symbiosis to reef-building corals and reef nutrient and carbon cycles is well documented, but little is known about the mechanisms by which the partners establish and regulate the symbiosis. Because the dinoflagellate symbionts live inside the cells of their host coral, the interactions between the partners occur on cellular and molecular levels, as each partner alters the expression of genes and proteins to facilitate the partnership. These interactions can examined using high-throughput techniques that allow thousands of genes to be examined simultaneously. We are developing the groundwork so that we can use DNA microarray profiling to identify genes involved in the Montastraea faveolata and Acropora palmata symbioses. Here we report results from the initial steps in this microarray initiative, that is, the construction of cDNA libraries from 4 of 16 target stages, sequencing of 3450 cDNA clones to generate Expressed Sequenced Tags (ESTs), and annotation of the ESTs to identify candidate genes to include in the microarrays. An understanding of how the coral-dinoflagellate symbiosis is regulated will have implications for atmospheric and ocean sciences, conservation biology, the study and diagnosis of coral bleaching and disease, and comparative studies of animal-protest interactions.

  11. Evolution of symbiosis with resource allocation from fecundity to survival

    NASA Astrophysics Data System (ADS)

    Fukui, Shin

    2014-05-01

    Symbiosis is one of the most fundamental relationships between or among organisms and includes parasitism (which has negative effects on the fitness of the interacting partner), commensalism (no effect), and mutualism (positive effects). The effects of these interactions are usually assumed to influence a single component of a species' fitness, either survival or fecundity, even though in reality the interaction can simultaneously affect both of these components. I used a dual lattice model to investigate the process of evolution of mutualistic symbiosis in the presence of interactive effects on both survival and fecundity. I demonstrate that a positive effect on survival and a negative effect on fecundity are key to the establishment of mutualism. Furthermore, both the parasitic and the mutualistic behaviour must carry large costs for mutualism to evolve. This helps develop a new understanding of symbiosis as a function of resource allocation, in which resources are shifted from fecundity to survival. The simultaneous establishment of mutualism from parasitism never occurs in two species, but can do so in one of the species as long as the partner still behaves parasitically. This suggests that one of the altruistic behaviours in a mutualistic unit consisting of two species must originate as a parasitic behaviour.

  12. Evolution of symbiosis with resource allocation from fecundity to survival.

    PubMed

    Fukui, Shin

    2014-05-01

    Symbiosis is one of the most fundamental relationships between or among organisms and includes parasitism (which has negative effects on the fitness of the interacting partner), commensalism (no effect), and mutualism (positive effects). The effects of these interactions are usually assumed to influence a single component of a species' fitness, either survival or fecundity, even though in reality the interaction can simultaneously affect both of these components. I used a dual lattice model to investigate the process of evolution of mutualistic symbiosis in the presence of interactive effects on both survival and fecundity. I demonstrate that a positive effect on survival and a negative effect on fecundity are key to the establishment of mutualism. Furthermore, both the parasitic and the mutualistic behaviour must carry large costs for mutualism to evolve. This helps develop a new understanding of symbiosis as a function of resource allocation, in which resources are shifted from fecundity to survival. The simultaneous establishment of mutualism from parasitism never occurs in two species, but can do so in one of the species as long as the partner still behaves parasitically. This suggests that one of the altruistic behaviours in a mutualistic unit consisting of two species must originate as a parasitic behaviour.

  13. Symbiosis through exploitation and the merger of lineages in evolution

    PubMed Central

    Law, R.; Dieckmann, U.

    1998-01-01

    A model for the coevolution of two species in facultative symbiosis is used to investigate conditions under which species merge to form a single reproductive unit. Two traits evolve in each species, the first affecting loss of resources from an individual to its partner, and the second affecting vertical transmission of the symbiosis from one generation to the next. Initial conditions are set so that the symbiosis involves exploitation of one partner by the other and vertical transmission is very rare. It is shown that, even in the face of continuing exploitation, a stable symbiotic unit can evolve with maximum vertical transmission of the partners. Such evolution requires that eventually deaths should exceed births for both species in the free-living state, a condition which can be met if the victim, in the course of developing its defences, builds up sufficiently large costs in the free-living state. This result expands the set of initial conditions from which separate lineages can be expected to merge into symbiotic units.

  14. A Medicago truncatula phosphate transporter indispensable for the arbuscular mycorrhizal symbiosis.

    PubMed

    Javot, Hélène; Penmetsa, R Varma; Terzaghi, Nadia; Cook, Douglas R; Harrison, Maria J

    2007-01-30

    The arbuscular mycorrhizal (AM) symbiosis is a mutualistic endosymbiosis formed by plant roots and AM fungi. Most vascular flowering plants have the ability to form these associations, which have a significant impact on plant health and consequently on ecosystem function. Nutrient exchange is a central feature of the AM symbiosis, and AM fungi obtain carbon from their plant host while assisting the plant with the acquisition of phosphorus (as phosphate) from the soil. In the AM symbiosis, the fungus delivers P(i) to the root through specialized hyphae called arbuscules. The molecular mechanisms of P(i) and carbon transfer in the symbiosis are largely unknown, as are the mechanisms by which the plant regulates the symbiosis in response to its nutrient status. Plants possess many classes of P(i) transport proteins, including a unique clade (Pht1, subfamily I), members of which are expressed only in the AM symbiosis. Here, we show that MtPT4, a Medicago truncatula member of subfamily I, is essential for the acquisition of P(i) delivered by the AM fungus. However, more significantly, MtPT4 function is critical for AM symbiosis. Loss of MtPT4 function leads to premature death of the arbuscules; the fungus is unable to proliferate within the root, and symbiosis is terminated. Thus, P(i) transport is not only a benefit for the plant but is also a requirement for the AM symbiosis.

  15. Complaints, complainants, and rulings regarding drug promotion in the United Kingdom and Sweden 2004-2012: a quantitative and qualitative study of pharmaceutical industry self-regulation.

    PubMed

    Zetterqvist, Anna V; Merlo, Juan; Mulinari, Shai

    2015-02-01

    In many European countries, medicines promotion is governed by voluntary codes of practice administered by the pharmaceutical industry under its own system of self-regulation. Involvement of industry organizations in policing promotion has been proposed to deter illicit conduct, but few detailed studies on self-regulation have been carried out to date. The objective of this study was to examine the evidence for promotion and self-regulation in the UK and Sweden, two countries frequently cited as examples of effective self-regulation. We performed a qualitative content analysis of documents outlining the constitutions and procedures of these two systems. We also gathered data from self-regulatory bodies on complaints, complainants, and rulings for the period 2004-2012. The qualitative analysis revealed similarities and differences between the countries. For example, self-regulatory bodies in both countries are required to actively monitor promotional items and impose sanctions on violating companies, but the range of sanctions is greater in the UK where companies may, for instance, be audited or publicly reprimanded. In total, Swedish and UK bodies ruled that 536 and 597 cases, respectively, were in breach, equating to an average of more than one case/week for each country. In Sweden, 430 (47%) complaints resulted from active monitoring, compared with only two complaints (0.2%) in the UK. In both countries, a majority of violations concerned misleading promotion. Charges incurred on companies averaged €447,000 and €765,000 per year in Sweden and the UK, respectively, equivalent to about 0.014% and 0.0051% of annual sales revenues, respectively. One hundred cases in the UK (17% of total cases in breach) and 101 (19%) in Sweden were highlighted as particularly serious. A total of 46 companies were ruled in breach of code for a serious offence at least once in the two countries combined (n = 36 in the UK; n = 27 in Sweden); seven companies were in serious violation

  16. Complaints, Complainants, and Rulings Regarding Drug Promotion in the United Kingdom and Sweden 2004–2012: A Quantitative and Qualitative Study of Pharmaceutical Industry Self-Regulation

    PubMed Central

    Zetterqvist, Anna V.; Merlo, Juan; Mulinari, Shai

    2015-01-01

    Background In many European countries, medicines promotion is governed by voluntary codes of practice administered by the pharmaceutical industry under its own system of self-regulation. Involvement of industry organizations in policing promotion has been proposed to deter illicit conduct, but few detailed studies on self-regulation have been carried out to date. The objective of this study was to examine the evidence for promotion and self-regulation in the UK and Sweden, two countries frequently cited as examples of effective self-regulation. Methods and Findings We performed a qualitative content analysis of documents outlining the constitutions and procedures of these two systems. We also gathered data from self-regulatory bodies on complaints, complainants, and rulings for the period 2004–2012. The qualitative analysis revealed similarities and differences between the countries. For example, self-regulatory bodies in both countries are required to actively monitor promotional items and impose sanctions on violating companies, but the range of sanctions is greater in the UK where companies may, for instance, be audited or publicly reprimanded. In total, Swedish and UK bodies ruled that 536 and 597 cases, respectively, were in breach, equating to an average of more than one case/week for each country. In Sweden, 430 (47%) complaints resulted from active monitoring, compared with only two complaints (0.2%) in the UK. In both countries, a majority of violations concerned misleading promotion. Charges incurred on companies averaged €447,000 and €765,000 per year in Sweden and the UK, respectively, equivalent to about 0.014% and 0.0051% of annual sales revenues, respectively. One hundred cases in the UK (17% of total cases in breach) and 101 (19%) in Sweden were highlighted as particularly serious. A total of 46 companies were ruled in breach of code for a serious offence at least once in the two countries combined (n = 36 in the UK; n = 27 in Sweden); seven

  17. Rhizobacteria and plant symbiosis in heavy metal uptake and its implications for soil bioremediation.

    PubMed

    Sobariu, Dana Luminița; Fertu, Daniela Ionela Tudorache; Diaconu, Mariana; Pavel, Lucian Vasile; Hlihor, Raluca-Maria; Drăgoi, Elena Niculina; Curteanu, Silvia; Lenz, Markus; Corvini, Philippe François-Xavier; Gavrilescu, Maria

    2016-09-09

    Certain species of plants can benefit from synergistic effects with plant growth-promoting rhizobacteria (PGPR) that improve plant growth and metal accumulation, mitigating toxic effects on plants and increasing their tolerance to heavy metals. The application of PGPR as biofertilizers and atmospheric nitrogen fixators contributes considerably to the intensification of the phytoremediation process. In this paper, we have built a system consisting of rhizospheric Azotobacter microbial populations and Lepidium sativum plants, growing in solutions containing heavy metals in various concentrations. We examined the ability of the organisms to grow in symbiosis so as to stimulate the plant growth and enhance its tolerance to Cr(VI) and Cd(II), to ultimately provide a reliable phytoremediation system. The study was developed at the laboratory level and, at this stage, does not assess the inherent interactions under real conditions occurring in contaminated fields with autochthonous microflora and under different pedoclimatic conditions and environmental stresses. Azotobacter sp. bacteria could indeed stimulate the average germination efficiency of Lepidium sativum by almost 7%, average root length by 22%, average stem length by 34% and dry biomass by 53%. The growth of L. sativum has been affected to a greater extent in Cd(II) solutions due its higher toxicity compared to that of Cr(VI). The reduced tolerance index (TI, %) indicated that plant growth in symbiosis with PGPR was however affected by heavy metal toxicity, while the tolerance of the plant to heavy metals was enhanced in the bacteria-plant system. A methodology based on artificial neural networks (ANNs) and differential evolution (DE), specifically a neuro-evolutionary approach, was applied to model germination rates, dry biomass and root/stem length and proving the robustness of the experimental data. The errors associated with all four variables are small and the correlation coefficients higher than 0

  18. Two putative-aquaporin genes are differentially expressed during arbuscular mycorrhizal symbiosis in Lotus japonicus

    PubMed Central

    2012-01-01

    Background Arbuscular mycorrhizas (AM) are widespread symbioses that provide great advantages to the plant, improving its nutritional status and allowing the fungus to complete its life cycle. Nevertheless, molecular mechanisms that lead to the development of AM symbiosis are not yet fully deciphered. Here, we have focused on two putative aquaporin genes, LjNIP1 and LjXIP1, which resulted to be upregulated in a transcriptomic analysis performed on mycorrhizal roots of Lotus japonicus. Results A phylogenetic analysis has shown that the two putative aquaporins belong to different functional families: NIPs and XIPs. Transcriptomic experiments have shown the independence of their expression from their nutritional status but also a close correlation with mycorrhizal and rhizobial interaction. Further transcript quantification has revealed a good correlation between the expression of one of them, LjNIP1, and LjPT4, the phosphate transporter which is considered a marker gene for mycorrhizal functionality. By using laser microdissection, we have demonstrated that one of the two genes, LjNIP1, is expressed exclusively in arbuscule-containing cells. LjNIP1, in agreement with its putative role as an aquaporin, is capable of transferring water when expressed in yeast protoplasts. Confocal analysis have demonstrated that eGFP-LjNIP1, under its endogenous promoter, accumulates in the inner membrane system of arbusculated cells. Conclusions Overall, the results have shown different functionality and expression specificity of two mycorrhiza-inducible aquaporins in L. japonicus. One of them, LjNIP1 can be considered a novel molecular marker of mycorrhizal status at different developmental stages of the arbuscule. At the same time, LjXIP1 results to be the first XIP family aquaporin to be transcriptionally regulated during symbiosis. PMID:23046713

  19. Analysis of copper tolerant rhizobacteria from the industrial belt of Gujarat, western India for plant growth promotion in metal polluted agriculture soils.

    PubMed

    Sharaff, Murali; Kamat, Shalmali; Archana, G

    2017-04-01

    Agricultural sites irrigated for long term with water polluted by industrial effluents containing heavy metals might adversely affect the soil microbial communities and crop yield. Hence it is important to study rhizobacterial communities and their metal tolerance in such affected agricultural fields to restore soil fertility and ecosystem. Present work deals with the study of rhizobacterial communities from plants grown in copper (Cu) contaminated agricultural fields along the industrial zone of Gujarat, India and are compared with communities from a Cu mine site. Microbial communities from rhizosphere soil samples varied in the magnitude of their Cu tolerance index indicating differences in long term pollution effects. Culture dependent denaturing gradient gel electrophoresis (CD-DGGE) of bacterial communities revealed the diverse composition at the sampling sites and a reduced total diversity due to Cu toxicity. Analysis of 16S rRNA gene diversity of Cu tolerant rhizobacteria revealed the predominance of Enterobacter spp. and Pseudomonas spp. under Cu stress conditions. Cu tolerant bacterial isolates that were able to promote growth of mung bean plants in vitro under Cu stress were obtained from these samples. Cu tolerant rhizobacterium P36 identified as Enterobacter sp. exhibited multiple plant growth promoting traits and significantly alleviated Cu toxicity to mung bean plants by reducing the accumulation of Cu in plant roots and promoted the plant growth in CuSO4 amended soils. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Symbiosis between nitrogen-fixing bacteria and Medicago truncatula is not significantly affected by silver and silver sulfide nanomaterials.

    PubMed

    Judy, Jonathan D; Kirby, Jason K; McLaughlin, Mike J; McNear, David; Bertsch, Paul M

    2016-07-01

    Silver (Ag) engineered nanomaterials (ENMs) are being released into waste streams and are being discharged, largely as Ag2S aged-ENMs (a-ENMs), into agroecosystems receiving biosolids amendments. Recent research has demonstrated that biosolids containing an environmentally relevant mixture of ZnO, TiO2, and Ag ENMs and their transformation products, including Ag2S a-ENMs, disrupted the symbiosis between nitrogen-fixing bacteria and legumes. However, this study was unable to unequivocally determine which ENM or combination of ENMs and a-ENMs was responsible for the observed inhibition. Here, we examined further the effects of polyvinylpyrollidone (PVP) coated pristine Ag ENMs (PVP-Ag), Ag2S a-ENMs, and soluble Ag (as AgSO4) at 1, 10, and 100 mg Ag kg(-1) on the symbiosis between the legume Medicago truncatula and the nitrogen-fixing bacterium, Sinorhizobium melliloti in biosolids-amended soil. Nodulation frequency, nodule function, glutathione reductase production, and biomass were not significantly affected by any of the Ag treatments, even at 100 mg kg(-1), a concentration analogous to a worst-case scenario resulting from long-term, repeated biosolids amendments. Our results provide additional evidence that the disruption of the symbiosis between nitrogen-fixing bacteria and legumes in response to a mixture of ENMs in biosolids-amended soil reported previously may not be attributable to Ag ENMs or their transformation end-products. We anticipate these findings will provide clarity to regulators and industry regarding potential unintended consequences to terrestrial ecosystems resulting from of the use of Ag ENMs in consumer products.

  1. Public/private sector cooperation to promote industrial energy efficiency: Allied partners and the US Department of Energy

    SciTech Connect

    McKane, Aimee; Cockrill, Chris; Tutterow, Vestal; Radspieler, Anthony

    2003-05-18

    Since 1996, the US Department of Energy's Office of Industrial Technologies (USDOE) has been involved in a unique voluntary collaboration with industry called the Allied Partner program. Initially developed under the Motor Challenge program, the partnership concept continues as a central element of USDOE's BestPractices, which in 2001 integrated all of USDOE's near-term industrial program offerings including those in motors, compressed air, pump, fan, process heating and steam systems. Partnerships are sought with end use industrial companies as well as equipment suppliers and manufacturers, utilities, consultants, and state agencies that have extensive existing relationships with industrial customers. Partners are neither paid nor charged a fee for participation. Since the inception of Allied Partners, the assumption has been that these relationships could serve as the foundation for conveying a system energy-efficiency message to many more industrial facilities than could be reached through a typical government-to-end-user program model. An independent evaluation of the Motor Challenge program, reported at the last EEMODS conference, attributed US $16.9 million or nearly 67 percent of the total annual program energy savings to the efforts of Allied Partners in the first three years of operation. A recent evaluation of the Compressed Air Challenger, which grew out of the former Motor Challenger program, attribute additional energy savings from compressed air training alone at US $12.1 million per year. Since the reorganization under BestPractices, the Allied Partner program has been reshaped to extend the impact of all BestPractices program activities. This new model is more ambitious than the former Motor Challenge program concerning the level of collaborative activities negotiated with Allied Partners. This paper describes in detail two new types of program initiatives involving Allied Partners: Qualified Specialist Training and Energy Events. The Qualified

  2. Using promoter replacement and selection for loss of heterozygosity to generate an industrially applicable sake yeast strain that homozygously overproduces isoamyl acetate.

    PubMed

    Sahara, Hiroshi; Kotaka, Atsushi; Kondo, Akihiko; Ueda, Mitsuyoshi; Hata, Yoji

    2009-11-01

    By application of the high-efficiency loss of heterozygosity (HELOH) method for disrupting genes in diploid sake yeast (Kotaka et al., Appl. Microbiol. Biotechnol., 82, 387-395 (2009)), we constructed, from a heterozygous integrant, a homozygous diploid that overexpresses the alcohol acetyltransferase gene ATF2 from the SED1 promoter, without the need for sporulation and mating. Under the conditions of sake brewing, the homozygous integrant produced 1.4 times more isoamyl acetate than the parental, heterozygous strain. Furthermore, the homozygous integrant was more genetically stable than the heterozygous recombinant. Thus, the HELOH method can produce homozygous, recombinant sake yeast that is ready to be grown on an industrial scale using the well-established procedures of sake brewing. The HELOH method, therefore, facilitates genetic modification of this rarely sporulating diploid yeast strain while maintaining those characteristics required for industrial applications.

  3. Arbuscular mycorrhizal symbiosis and osmotic adjustment in response to NaCl stress: a meta-analysis

    PubMed Central

    Augé, Robert M.; Toler, Heather D.; Saxton, Arnold M.

    2014-01-01

    Arbuscular mycorrhizal (AM) symbiosis can enhance plant resistance to NaCl stress in several ways. Two fundamental roles involve osmotic and ionic adjustment. By stimulating accumulation of solutes, the symbiosis can help plants sustain optimal water balance and diminish Na+ toxicity. The size of the AM effect on osmolytes has varied widely and is unpredictable. We conducted a meta-analysis to determine the size of the AM effect on 22 plant solute characteristics after exposure to NaCl and to examine how experimental conditions have influenced the AM effect. Viewed across studies, AM symbioses have had marked effects on plant K+, increasing root and shoot K+ concentrations by an average of 47 and 42%, respectively, and root and shoot K+/Na+ ratios by 47 and 58%, respectively. Among organic solutes, soluble carbohydrates have been most impacted, with AM-induced increases of 28 and 19% in shoots and roots. The symbiosis has had no consistent effect on several characteristics, including root glycine betaine concentration, root or shoot Cl− concentrations, leaf Ψπ, or shoot proline or polyamine concentrations. The AM effect has been very small for shoot Ca++ concentration and root concentrations of Na+, Mg++ and proline. Interpretations about AM-conferred benefits regarding these compounds may be best gauged within the context of the individual studies. Shoot and root K+/Na+ ratios and root proline concentration showed significant between-study heterogeneity, and we examined nine moderator variables to explore what might explain the differences in mycorrhizal effects on these parameters. Moderators with significant impacts included AM taxa, host type, presence or absence of AM growth promotion, stress severity, and whether NaCl constituted part or all of the experimental saline stress treatment. Meta-regression of shoot K+/Na+ ratio showed a positive response to root colonization, and root K+/Na+ ratio a negative response to time of exposure to NaCl. PMID:25368626

  4. Impediment to symbiosis establishment between giant clams and Symbiodinium algae due to sterilization of seawater.

    PubMed

    Kurihara, Takeo; Yamada, Hideaki; Inoue, Ken; Iwai, Kenji; Hatta, Masayuki

    2013-01-01

    To survive the juvenile stage, giant clam juveniles need to establish a symbiotic relationship with the microalgae Symbiodinium occurring in the environment. The percentage of giant clam juveniles succeeding in symbiosis establishment ("symbiosis rate") is often low, which is problematic for seed producers. We investigated how and why symbiosis rates vary, depending on whether giant clam seeds are continuously reared in UV treated or non treated seawater. Results repeatedly demonstrated that symbiosis rates were lower for UV treated seawater than for non treated seawater. Symbiosis rates were also lower for autoclaved seawater and 0.2-µm filtered seawater than for non treated seawater. The decreased symbiosis rates in various sterilized seawater suggest the possibility that some factors helping symbiosis establishment in natural seawater are weakened owing to sterilization. The possible factors include vitality of giant clam seeds, since additional experiments revealed that survival rates of seeds reared alone without Symbiodinium were lower in sterilized seawater than in non treated seawater. In conclusion, UV treatment of seawater was found to lead to decreased symbiosis rates, which is due possibly to some adverse effects common to the various sterilization techniques and relates to the vitality of the giant clam seeds.

  5. Impediment to Symbiosis Establishment between Giant Clams and Symbiodinium Algae Due to Sterilization of Seawater

    PubMed Central

    Kurihara, Takeo; Yamada, Hideaki; Inoue, Ken; Iwai, Kenji; Hatta, Masayuki

    2013-01-01

    To survive the juvenile stage, giant clam juveniles need to establish a symbiotic relationship with the microalgae Symbiodinium occurring in the environment. The percentage of giant clam juveniles succeeding in symbiosis establishment (“symbiosis rate”) is often low, which is problematic for seed producers. We investigated how and why symbiosis rates vary, depending on whether giant clam seeds are continuously reared in UV treated or non treated seawater. Results repeatedly demonstrated that symbiosis rates were lower for UV treated seawater than for non treated seawater. Symbiosis rates were also lower for autoclaved seawater and 0.2-µm filtered seawater than for non treated seawater. The decreased symbiosis rates in various sterilized seawater suggest the possibility that some factors helping symbiosis establishment in natural seawater are weakened owing to sterilization. The possible factors include vitality of giant clam seeds, since additional experiments revealed that survival rates of seeds reared alone without Symbiodinium were lower in sterilized seawater than in non treated seawater. In conclusion, UV treatment of seawater was found to lead to decreased symbiosis rates, which is due possibly to some adverse effects common to the various sterilization techniques and relates to the vitality of the giant clam seeds. PMID:23613802

  6. Carbon availability for the fungus triggers nitrogen uptake and transport in the arbuscular mycorrhizal symbiosis

    USDA-ARS?s Scientific Manuscript database

    The arbuscular mycorrhizal (AM) symbiosis is characterized by a transfer of nutrients in exchange for carbon. We tested the effect of the carbon availability for the AM fungus Glomus intraradices on nitrogen (N) uptake and transport in the symbiosis. We followed the uptake and transport of 15N and ...

  7. Building an Entrepreneurial University in Brazil: The Role and Potential of University-Industry Linkages in Promoting Regional Economic Development

    ERIC Educational Resources Information Center

    Amaral, Marcelo; Ferreira, Andre; Teodoro, Pitias

    2011-01-01

    This study is part of a broader research project, conducted by the Triple Helix Research Group--Brazil, focusing on university-industry-government linkages in the state of Rio de Janeiro. The case study reported here is that of the Regional University of Volta Redonda: the aim was to develop an understanding of how a regional university can be…

  8. Mechanisms underlying beneficial plant-fungus interactions in mycorrhizal symbiosis.

    PubMed

    Bonfante, Paola; Genre, Andrea

    2010-07-27

    Mycorrhizal fungi are a heterogeneous group of diverse fungal taxa, associated with the roots of over 90% of all plant species. Recently, state-of-the-art molecular and genetic tools, coupled to high-throughput sequencing and advanced microscopy, have led to the genome and transcriptome analysis of several symbionts. Signalling pathways between plants and fungi have now been described and the identification of several novel nutrient transporters has revealed some of the cellular processes that underlie symbiosis. Thus, the contributions of each partner in a mycorrhizal association are starting to be unravelled. This new knowledge is now available for use in agricultural practices.

  9. Persistent virus and addiction modules: an engine of symbiosis.

    PubMed

    Villarreal, Luis P

    2016-06-01

    The giant DNA viruses are highly prevalent and have a particular affinity for the lytic infection of unicellular eukaryotic host. The giant viruses can also be infected by inhibitory virophage which can provide lysis protection to their host. The combined protective and destructive action of such viruses can define a general model (PD) of virus-mediated host survival. Here, I present a general model for role such viruses play in the evolution of host symbiosis. By considering how virus mixtures can participate in addiction modules, I provide a functional explanation for persistence of virus derived genetic 'junk' in their host genomic habitats.

  10. Sustainable agriculture: possible trajectories from mutualistic symbiosis and plant neodomestication.

    PubMed

    Duhamel, Marie; Vandenkoornhuyse, Philippe

    2013-11-01

    Food demand will increase concomitantly with human population. Food production therefore needs to be high enough and, at the same time, minimize damage to the environment. This equation cannot be solved with current strategies. Based on recent findings, new trajectories for agriculture and plant breeding which take into account the belowground compartment and evolution of mutualistic strategy, are proposed in this opinion article. In this context, we argue that plant breeders have the opportunity to make use of native arbuscular mycorrhizal (AM) symbiosis in an innovative ecologically intensive agriculture. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Stars and Symbiosis: MicroRNA- and MicroRNA*-Mediated Transcript Cleavage Involved in Arbuscular Mycorrhizal Symbiosis1[W][OA

    PubMed Central

    Devers, Emanuel A.; Branscheid, Anja; May, Patrick; Krajinski, Franziska

    2011-01-01

    The majority of plants are able to form the arbuscular mycorrhizal (AM) symbiosis in association with AM fungi. During symbiosis development, plant cells undergo a complex reprogramming resulting in profound morphological and physiological changes. MicroRNAs (miRNAs) are important components of the regulatory network of plant cells. To unravel the impact of miRNAs and miRNA-mediated mRNA cleavage on root cell reprogramming during AM symbiosis, we carried out high-throughput (Illumina) sequencing of small RNAs and degradome tags of Medicago truncatula roots. This led to the annotation of 243 novel miRNAs. An increased accumulation of several novel and conserved miRNAs in mycorrhizal roots suggest a role of these miRNAs during AM symbiosis. The degradome analysis led to the identification of 185 root transcripts as mature miRNA and also miRNA*-mediated mRNA cleavage targets. Several of the identified miRNA targets are known to be involved in root symbioses. In summary, the increased accumulation of specific miRNAs and the miRNA-mediated cleavage of symbiosis-relevant genes indicate that miRNAs are an important part of the regulatory network leading to symbiosis development. PMID:21571671

  12. Discarded oranges and brewer's spent grains as promoting ingredients for microbial growth by submerged and solid state fermentation of agro-industrial waste mixtures.

    PubMed

    Aggelopoulos, Theodoros; Bekatorou, Argyro; Pandey, Ashok; Kanellaki, Maria; Koutinas, Athanasios A

    2013-08-01

    The exploitation of various agro-industrial wastes for microbial cell mass production of Kluyveromyces marxianus, kefir, and Saccharomyces cerevisiae is reported in the present investigation. Specifically, the promotional effect of whole orange pulp on cell growth in mixtures consisting of cheese whey, molasses, and potato pulp in submerged fermentation processes was examined. A 2- to 3-fold increase of cell mass was observed in the presence of orange pulp. Likewise, the promotional effect of brewer's spent grains on cell growth in solid state fermentation of mixtures of whey, molasses, potato pulp, malt spent rootlets, and orange pulp was examined. The cell mass was increased by 3-fold for K. marxianus and 2-fold for S. cerevisiae in the presence of these substrates, proving their suitability for single-cell protein production without the need for extra nutrients. Cell growth kinetics were also studied by measurements of cell counts at various time intervals at different concentrations of added orange pulp. The protein content of the fermented substrates was increased substantially, indicating potential use of mixed agro-industrial wastes of negligible cost, as protein-enriched livestock feed, achieving at the same time creation of added value and waste minimization.

  13. Value of the Hydra model system for studying symbiosis.

    PubMed

    Kovacevic, Goran

    2012-01-01

    Green Hydra is used as a classical example for explaining symbiosis in schools as well as an excellent research model. Indeed the cosmopolitan green Hydra (Hydra viridissima) provides a potent experimental framework to investigate the symbiotic relationships between a complex eumetazoan organism and a unicellular photoautotrophic green algae named Chlorella. Chlorella populates a single somatic cell type, the gastrodermal myoepithelial cells (also named digestive cells) and the oocyte at the time of sexual reproduction. This symbiotic relationship is stable, well-determined and provides biological advantages to the algal symbionts, but also to green Hydra over the related non-symbiotic Hydra i.e. brown hydra. These advantages likely result from the bidirectional flow of metabolites between the host and the symbiont. Moreover genetic flow through horizontal gene transfer might also participate in the establishment of these selective advantages. However, these relationships between the host and the symbionts may be more complex. Thus, Jolley and Smith showed that the reproductive rate of the algae increases dramatically outside of Hydra cells, although this endosymbiont isolation is debated. Recently it became possible to keep different species of endosymbionts isolated from green Hydra in stable and permanent cultures and compare them to free-living Chlorella species. Future studies testing metabolic relationships and genetic flow should help elucidate the mechanisms that support the maintenance of symbiosis in a eumetazoan species.

  14. Methanotrophic marine molluscan (Bivalvia, Mytilidae) symbiosis: mussels fueled by gas

    SciTech Connect

    Childress, J.J.; Fisher, C.R.; Brooks, J.M.; Kennicutt, M.C. II; Bidigare, R.; Anderson, A.E.

    1986-09-19

    An undescribed mussel (family Mytilidae), which lives in the vicinity of hydrocarbon seeps in the Gulf of Mexico, consumes methane (the principal component of natural gas) at a high rate. The methane consumption is limited to the gills of these animals and is apparently due to the abundant intracellular bacteria found there. This demonstrates a methane-based symbiosis between an animal and intracellular bacteria. Methane consumption is dependent on the availability of oxygen and is inhibited by acetylene. The consumption of methane by these mussels is associated with a dramatic increase in oxygen consumption and carbon dioxide production. As the methane consumption of the bivalve can exceed its carbide dioxide production, the symbiosis may be able to entirely satisfy its carbon needs from methane uptake. The very light (delta/sup 13/C = -51 to -57 per mil) stable carbon isotope ratios found in this animal support methane (delta/sup 13/C = -45 per mil at this site) as the primary carbon source for both the mussels and their symbionts. 19 references, 2 figures, 1 table.

  15. Cell biology of the chloroplast symbiosis in sacoglossan sea slugs.

    PubMed

    Pierce, Sidney K; Curtis, Nicholas E

    2012-01-01

    Chloroplasts removed from their species of origin may survive for various periods and even photosynthesize in foreign cells. One of the best studied and impressively long, naturally occurring examples of chloroplast persistence, and function inside foreign cells are the algal chloroplasts taken up by specialized cells of certain sacoglossan sea slugs, a phenomenon called chloroplast symbiosis or kleptoplasty. Among sacoglossan species, kleptoplastic associations vary widely in length and function, with some animals immediately digesting chloroplasts, while others maintain functional plastids for over 10 months. Kleptoplasty is a complex process in long-term associations, and research on this topic has focused on a variety of aspects including plastid uptake and digestive physiology of the sea slugs, the longevity and maintenance of symbiotic associations, biochemical interactions between captured algal plastids and slug cells, and the role of horizontal gene transfers between the sea slug and algal food sources. Although the biochemistry underlying chloroplast symbiosis has been extensively examined in only a few slug species, it is obvious that the mechanisms vary from species to species. In this chapter, we examine those mechanisms from early discoveries to the most current research. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Metabolic and physiological interdependencies in the Bathymodiolus azoricus symbiosis.

    PubMed

    Ponnudurai, Ruby; Kleiner, Manuel; Sayavedra, Lizbeth; Petersen, Jillian M; Moche, Martin; Otto, Andreas; Becher, Dörte; Takeuchi, Takeshi; Satoh, Noriyuki; Dubilier, Nicole; Schweder, Thomas; Markert, Stephanie

    2017-02-01

    The hydrothermal vent mussel Bathymodiolus azoricus lives in an intimate symbiosis with two types of chemosynthetic Gammaproteobacteria in its gills: a sulfur oxidizer and a methane oxidizer. Despite numerous investigations over the last decades, the degree of interdependence between the three symbiotic partners, their individual metabolic contributions, as well as the mechanism of carbon transfer from the symbionts to the host are poorly understood. We used a combination of proteomics and genomics to investigate the physiology and metabolism of the individual symbiotic partners. Our study revealed that key metabolic functions are most likely accomplished jointly by B. azoricus and its symbionts: (1) CO2 is pre-concentrated by the host for carbon fixation by the sulfur-oxidizing symbiont, and (2) the host replenishes essential biosynthetic TCA cycle intermediates for the sulfur-oxidizing symbiont. In return (3), the sulfur oxidizer may compensate for the host's putative deficiency in amino acid and cofactor biosynthesis. We also identified numerous 'symbiosis-specific' host proteins by comparing symbiont-containing and symbiont-free host tissues and symbiont fractions. These proteins included a large complement of host digestive enzymes in the gill that are likely involved in symbiont digestion and carbon transfer from the symbionts to the host.

  17. Metabolic and physiological interdependencies in the Bathymodiolus azoricus symbiosis

    PubMed Central

    Ponnudurai, Ruby; Kleiner, Manuel; Sayavedra, Lizbeth; Petersen, Jillian M; Moche, Martin; Otto, Andreas; Becher, Dörte; Takeuchi, Takeshi; Satoh, Noriyuki; Dubilier, Nicole; Schweder, Thomas; Markert, Stephanie

    2017-01-01

    The hydrothermal vent mussel Bathymodiolus azoricus lives in an intimate symbiosis with two types of chemosynthetic Gammaproteobacteria in its gills: a sulfur oxidizer and a methane oxidizer. Despite numerous investigations over the last decades, the degree of interdependence between the three symbiotic partners, their individual metabolic contributions, as well as the mechanism of carbon transfer from the symbionts to the host are poorly understood. We used a combination of proteomics and genomics to investigate the physiology and metabolism of the individual symbiotic partners. Our study revealed that key metabolic functions are most likely accomplished jointly by B. azoricus and its symbionts: (1) CO2 is pre-concentrated by the host for carbon fixation by the sulfur-oxidizing symbiont, and (2) the host replenishes essential biosynthetic TCA cycle intermediates for the sulfur-oxidizing symbiont. In return (3), the sulfur oxidizer may compensate for the host's putative deficiency in amino acid and cofactor biosynthesis. We also identified numerous ‘symbiosis-specific' host proteins by comparing symbiont-containing and symbiont-free host tissues and symbiont fractions. These proteins included a large complement of host digestive enzymes in the gill that are likely involved in symbiont digestion and carbon transfer from the symbionts to the host. PMID:27801908

  18. An ancient tripartite symbiosis of plants, ants and scale insects.

    PubMed

    Ueda, Shouhei; Quek, Swee-Peck; Itioka, Takao; Inamori, Keita; Sato, Yumiko; Murase, Kaori; Itino, Takao

    2008-10-22

    In the Asian tropics, a conspicuous radiation of Macaranga plants is inhabited by obligately associated Crematogaster ants tending Coccus (Coccidae) scale insects, forming a tripartite symbiosis. Recent phylogenetic studies have shown that the plants and the ants have been codiversifying over the past 16-20 million years (Myr). The prevalence of coccoids in ant-plant mutualisms suggest that they play an important role in the evolution of ant-plant symbioses. To determine whether the scale insects were involved in the evolutionary origin of the mutualism between Macaranga and Crematogaster, we constructed a cytochrome oxidase I (COI) gene phylogeny of the scale insects collected from myrmecophytic Macaranga and estimated their time of origin based on a COI molecular clock. The minimum age of the associated Coccus was estimated to be half that of the ants, at 7-9Myr, suggesting that they were latecomers in the evolutionary history of the symbiosis. Crematogaster mitochondrial DNA (mtDNA) lineages did not exhibit specificity towards Coccus mtDNA lineages, and the latter was not found to be specific towards Macaranga taxa, suggesting that patterns of associations in the scale insects are dictated by opportunity rather than by specialized adaptations to host plant traits.

  19. Diminished exoproteome of Frankia spp. in culture and symbiosis.

    PubMed

    Mastronunzio, J E; Huang, Y; Benson, D R

    2009-11-01

    Frankia species are the most geographically widespread gram-positive plant symbionts, carrying out N(2) fixation in root nodules of trees and woody shrubs called actinorhizal plants. Taking advantage of the sequencing of three Frankia genomes, proteomics techniques were used to investigate the population of extracellular proteins (the exoproteome) from Frankia, some of which potentially mediate host-microbe interactions. Initial two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of culture supernatants indicated that cytoplasmic proteins appeared in supernatants as cells aged, likely because older hyphae lyse in this slow-growing filamentous actinomycete. Using liquid chromatography coupled to tandem mass spectrometry to identify peptides, 38 proteins were identified in the culture supernatant of Frankia sp. strain CcI3, but only three had predicted export signal peptides. In symbiotic cells, 42 signal peptide-containing proteins were detected from strain CcI3 in Casuarina cunninghamiana and Casuarina glauca root nodules, while 73 and 53 putative secreted proteins containing signal peptides were identified from Frankia strains in field-collected root nodules of Alnus incana and Elaeagnus angustifolia, respectively. Solute-binding proteins were the most commonly identified secreted proteins in symbiosis, particularly those predicted to bind branched-chain amino acids and peptides. These direct proteomics results complement a previous bioinformatics study that predicted few secreted hydrolytic enzymes in the Frankia proteome and provide direct evidence that the symbiosis succeeds partly, if not largely, because of a benign relationship.

  20. Nitric oxide detoxification in the rhizobia-legume symbiosis.

    PubMed

    Sánchez, Cristina; Cabrera, Juan J; Gates, Andrew J; Bedmar, Eulogio J; Richardson, David J; Delgado, María J

    2011-01-01

    NO (nitric oxide) is a signal molecule involved in diverse physiological processes in cells which can become very toxic under certain conditions determined by its rate of production and diffusion. Several studies have clearly shown the production of NO in early stages of rhizobia-legume symbiosis and in mature nodules. In functioning nodules, it has been demonstrated that NO, which has been reported as a potent inhibitor of nitrogenase activity, can bind Lb (leghaemoglobin) to form LbNOs (nitrosyl-leghaemoglobin complexes). These observations have led to the question of how nodules overcome the toxicity of NO. On the bacterial side, one candidate for NO detoxification in nodules is the respiratory Nor (NO reductase) that catalyses the reduction of NO to nitrous oxide. In addition, rhizobial fHbs (flavohaemoglobins) and single-domain Hbs which dioxygenate NO to form nitrate are candidates to detoxify NO under free-living and symbiotic conditions. On the plant side, sHbs (symbiotic Hbs) (Lb) and nsHbs (non-symbiotic Hbs) have been proposed to play important roles as modulators of NO levels in the rhizobia-legume symbiosis. In the present review, current knowledge of NO detoxification by legume-associated endosymbiotic bacteria is summarized.

  1. Effects of multiple climate change factors on the tall fescue-fungal endophyte symbiosis: infection frequency and tissue chemistry.

    SciTech Connect

    Brosi, Glade; McCulley, Rebecca L; Bush, L P; Nelson, Jim A; Classen, Aimee T; Norby, Richard J

    2011-01-01

    Climate change (altered CO{sub 2}, warming, and precipitation) may affect plant-microbial interactions, such as the Lolium arundinaceum-Neotyphodium coenophialum symbiosis, to alter future ecosystem structure and function. To assess this possibility, tall fescue tillers were collected from an existing climate manipulation experiment in a constructed old-field community in Tennessee (USA). Endophyte infection frequency (EIF) was determined, and infected (E+) and uninfected (E-) tillers were analysed for tissue chemistry. The EIF of tall fescue was higher under elevated CO{sub 2} (91% infected) than with ambient CO{sub 2} (81%) but was not affected by warming or precipitation treatments. Within E+ tillers, elevated CO{sub 2} decreased alkaloid concentrations of both ergovaline and loline, by c. 30%; whereas warming increased loline concentrations 28% but had no effect on ergovaline. Independent of endophyte infection, elevated CO{sub 2} reduced concentrations of nitrogen, cellulose, hemicellulose, and lignin. These results suggest that elevated CO{sub 2}, more than changes in temperature or precipitation, may promote this grass-fungal symbiosis, leading to higher EIF in tall fescue in old-field communities. However, as all three climate factors are likely to change in the future, predicting the symbiotic response and resulting ecological consequences may be difficult and dependent on the specific atmospheric and climatic conditions encountered.

  2. Beyond Food Promotion: A Systematic Review on the Influence of the Food Industry on Obesity-Related Dietary Behaviour among Children.

    PubMed

    Sonntag, Diana; Schneider, Sarah; Mdege, Noreen; Ali, Shehzad; Schmidt, Burkhard

    2015-10-16

    An increased consumption of energy-dense, nutrient-poor food and beverages as a result of a changing obesogenic environment contributes substantially to the increasing prevalence of childhood overweight and obesity. This paper reviews the nature and extent of food industry influences which expose children to commercial influences and thus might affect unhealthy dietary behaviour and finally contributes to obesity. A systematic search of nine electronic databases (including PubMed, PsycINFO, EconLit) and reference lists of original studies and reviews using key search terms identified 1900 articles. Of these only thirty-six articles met the inclusion and quality criteria. A narrative synthesis of the reviewed studies revealed six key obesogenic environments by which the food industry possibly influences obesity-related dietary behaviours in young children. These were schools, retailers, mass media "television", mass media "internet", home and promotional campaigns. Identifying these obesogenic environments is critical for monitoring and controlling the food industry, the development of effective environmental-level interventions to prevent childhood overweight and obesity and to identify knowledge gaps to be addressed in future research to support informed decisions of policy makers.

  3. Beyond Food Promotion: A Systematic Review on the Influence of the Food Industry on Obesity-Related Dietary Behaviour among Children

    PubMed Central

    Sonntag, Diana; Schneider, Sarah; Mdege, Noreen; Ali, Shehzad; Schmidt, Burkhard

    2015-01-01

    An increased consumption of energy-dense, nutrient-poor food and beverages as a result of a changing obesogenic environment contributes substantially to the increasing prevalence of childhood overweight and obesity. This paper reviews the nature and extent of food industry influences which expose children to commercial influences and thus might affect unhealthy dietary behaviour and finally contributes to obesity. A systematic search of nine electronic databases (including PubMed, PsycINFO, EconLit) and reference lists of original studies and reviews using key search terms identified 1900 articles. Of these only thirty-six articles met the inclusion and quality criteria. A narrative synthesis of the reviewed studies revealed six key obesogenic environments by which the food industry possibly influences obesity-related dietary behaviours in young children. These were schools, retailers, mass media “television”, mass media “internet”, home and promotional campaigns. Identifying these obesogenic environments is critical for monitoring and controlling the food industry, the development of effective environmental-level interventions to prevent childhood overweight and obesity and to identify knowledge gaps to be addressed in future research to support informed decisions of policy makers. PMID:26501319

  4. Restoring balance to industry-academia relationships in an era of institutional financial conflicts of interest: promoting research while maintaining trust.

    PubMed

    Johns, Michael M E; Barnes, Mark; Florencio, Patrik S

    2003-02-12

    Economic partnerships between industry and academia accelerate medical innovation and enhance patient access to medical advances, but such partnerships have sometimes eroded public trust in the research enterprise. There is particular risk for conflict of interest when economic partnerships extend beyond a university's corporate interests to involve institutional decision makers. Institutions and institutional decision makers should fully disclose industry-related financial interests and relationships. Without legitimate justification for such interests, individuals should divest themselves from these interests or recuse themselves from responsibility for research oversight. Management of institutional partnerships also might entail the physical separation of certain facilities, the placement of restrictions on information shared between investment and research staffs, and provision of oversight by independent review panels made up of persons who have expertise in intellectual property, finance, and research, but who are not financially or otherwise dependent on the institution. Through these means, it is possible to restore balance to industry-academia relationships, thereby promoting progress while maintaining public trust in research.

  5. The DOE s In-Plant Training (INPLT) Model to Promote Energy Efficiency in the Industrial Sector

    SciTech Connect

    Alkadi, Nasr E; Nimbalkar, Sachin U; De Fontaine, Mr. Andre; Schoeneborn, Fred C

    2013-01-01

    In-Plant Training (INPLT) is a new model for developing energy efficiency expertise within the US manufacturing companies participating in the U.S. Department of Energy s (DOE s) Better Buildings, Better Plants Program-a nationwide initiative to drive a 25% reduction in industrial energy intensity in 10 years. INPLTs are designed to fill a market niche by providing hands on training in a real world manufacturing plant environment. Through INPLTs, participants from multiple manufacturing plants, supply chains, utilities, and other external stakeholders learn how to conduct energy assessments, use energy analysis tools to analyze energy saving opportunities, develop energy management systems, and implement energy savings projects. Typical INPLT events are led by DOE-certified Energy Experts and range from 2-4 days. Topics discussed include: identification of cross-cutting or system specific opportunities; introduction to ISO 50001 Energy Management Systems; and energy project implementation and replication. This model is flexible, and can be tailored to suit the needs of specific industries. The INPLTs are a significant departure from the traditional single plant energy assessment model previously employed by DOE. INPLTs shift the focus from the concept of a single-plant s energy profile to a broader focus on training and capacity building among multiple industrial participants. The objective is to enable trainees to identify, quantify, implement and replicate future energy saving projects without continued external assistance. This paper discusses the INPLT model and highlights some of the initial outcomes from the successfully delivered INPLTs and the overall impact in terms of numbers of plants/participants trained, impacted energy footprints, and potential replication of identified opportunities.

  6. Arsenic-resistant and plant growth-promoting Firmicutes and γ-Proteobacteria species from industrially polluted irrigation water and corresponding cropland.

    PubMed

    Qamar, N; Rehman, Y; Hasnain, S

    2017-09-01

    The aim of the study was to explore irrigation water polluted with industrial waste and corresponding cropland to screen bacteria for As detoxification and plant growth promotion. Plant growth-promoting (PGP) As-resistant cropland bacteria were isolated from contaminated irrigation water and corresponding agricultural soil. Phylogenetic analysis revealed that the isolates belonged to two distinct bacterial lineages; Firmicutes and γ-Proteobacteria. Maximum As(V) resistance was exhibited by Klebsiella pneumoniae T22 and Klebsiella oxytoca N53 (550 mmol l(-1) ), whereas maximum resistance against As(III) was exhibited by K. oxytoca N53 (200 mmol l(-1) ). Maximum As(V) reduction was shown by K. pneumoniae T22 (6·7 mmol l(-1) ), whereas maximum As(III) oxidation was exhibited by Bacillus subtilis T23 (4·8 mmol l(-1) ). As resistance genes arsB and ACR3 were detected in many of the isolates through polymerase chain reaction. Many of these isolates exhibited PGP traits such as hydrogen cyanide and auxin production as well as phosphate solubilization. The bacterial strains were able to enhance Triticum aestivum growth both in the absence and presence of As, and statistically significant increase in shoot and root lengths was observed especially in case of Acinetobacter lwoffii T24 and Citrobacter freundii N52-treated plants. Cropland bacteria have the ability to support plant growth. Bacteria of croplands irrigated with industrially polluted water develop resistance against toxicants. These bacteria are helpful for the plant growth in such contaminated lands. The bacteria capable of both As detoxification and plant growth promotion, such as A. lwoffii T24 and C. freundii N52, are ideal for remediation and reclamation of polluted lands for agriculture purposes. © 2017 The Society for Applied Microbiology.

  7. Phosphate in the arbuscular mycorrhizal symbiosis: transport properties and regulatory roles.

    PubMed

    Javot, Hélène; Pumplin, Nathan; Harrison, Maria J

    2007-03-01

    In response to the colonization by arbuscular mycorrhizal (AM) fungi, plants reprioritize their phosphate (Pi)-uptake strategies to take advantage of nutrient transfer via the fungus. The mechanisms underlying Pi transport are beginning to be understood, and recently, details of the regulation of plant and fungal Pi transporters in the AM symbiosis have been revealed. This review summarizes recent advances in this area and explores current data and hypotheses of how the plant Pi status affects the symbiosis. Finally, suggestions of an interrelationship of Pi and nitrogen (N) in the AM symbiosis are discussed.

  8. Possible Benefits of Mycorrhizal Symbiosis, in Reducing CO2 from Environment

    NASA Astrophysics Data System (ADS)

    Azmat, Rafia

    2013-12-01

    It is a fact that the relationship between a fungus and a plant can have a great impact on the environment, especially under drought conditions. Experiments conducted at the laboratory scale suggested that in mycorrhizal symbiosis; plants usually provide their fungal partners with carbohydrates from photosynthesis and receive mineral nutrients. It is observed that mycorrhizal inoculated plants observed large surface area of leaves and outsized root sections which were helpful in increasing the rate of photosynthetic processes. This may be attributed to the rapid production of carbohydrate for their fungal mate. The same phenomena can be observed in environments of high traffic density or waste burning, industrial zones (where there are emissions of CO2 from chimneys) or the areas that are lack nutrients such as nitrogen and phosphorus. It may be observed that the plants that have this association with mycorrhizal fungi may obligate a better chance in inhabiting this area. These plants can be helpful in reducing the CO2 from the polluted atmosphere. The large length of the roots were related to the absorption of water molecules for survival as well as formation of first organic complex CHO for providing the energy to the plant in biotic stress and C and nutrient exchange between fungal partner and plants.

  9. Nuclear energy and waste management pyroprocess for system symbiosis

    NASA Astrophysics Data System (ADS)

    Ogawa, Toru; Minato, Kazuo; Okamoto, Yoshihiro; Nishihara, Kenji

    2007-01-01

    The actinide management has become a key issue in nuclear energy. Recovering and fissioning transuranium elements reduce the long-term proliferation risks and the environmental burden. The better way of waste management will be made by system symbiosis: a combination of light-water reactor and fast reactor and/or accelerator-driven transmutation system should be sought. The new recycling technology should be able to achieve good economy with smaller plants, which can process fuels from different types of reactors on a common technical basis. Ease in handling the higher heat load of transuranium nuclides is also important. Pyroprocesses with the use of molten salts are regarded as the strong candidate for such recycling technology. In JAEA, the first laboratory for the high-temperature chemistry of Am and Cm has been established. The fundamental data will be combined with the computer code for predicting the molten-salts electrolytic processes.

  10. Lipopolysaccharide mutants of Rhizobium meliloti are not defective in symbiosis

    SciTech Connect

    Clover, R.H.; Kieber, J.; Signer, E.R. )

    1989-07-01

    Mutants of Rhizobium meliloti selected primarily for bacteriophage resistance fall into 13 groups. Mutants in the four best-characterized groups (class A, lpsB, lpsC, and class D), which map to the rhizobial chromosome, appear to affect lipopolysaccharide (LPS) as judged by the reactivity with monoclonal antibodies and behavior on sodium dodecyl sulfate-polyacrylamide gels of extracted LPS. Mutations in all 13 groups, in an otherwise wild-type genetic background, are Fix{sup +} on alfalfa. This suggests that LPS does not play a major role in symbiosis. Mutations in lpsB, however, are Fix{sup {minus}} in one particular genetic background, evidently because of the cumulative effect of several independent background mutations. In addition, an auxotrophic mutation evidently equivalent to Escherichia coli carAB is Fix{sup {minus}} on alfalfa.

  11. Evolutionary innovation: a bone-eating marine symbiosis.

    PubMed

    Goffredi, Shana K; Orphan, Victoria J; Rouse, Greg W; Jahnke, Linda; Embaye, Tsegeria; Turk, Kendra; Lee, Ray; Vrijenhoek, Robert C

    2005-09-01

    Symbiotic associations between microbes and invertebrates have resulted in some of the most unusual physiological and morphological adaptations that have evolved in the animal world. We document a new symbiosis between marine polychaetes of the genus Osedax and members of the bacterial group Oceanospirillales, known for heterotrophic degradation of complex organic compounds. These organisms were discovered living on the carcass of a grey whale at 2891 m depth in Monterey Canyon, off the coast of California. The mouthless and gutless worms are unique in their morphological specializations used to obtain nutrition from decomposing mammalian bones. Adult worms possess elaborate posterior root-like extensions that invade whale bone and contain bacteriocytes that house intracellular symbionts. Stable isotopes and fatty acid analyses suggest that these unusual endosymbionts are likely responsible for the nutrition of this locally abundant and reproductively prolific deep-sea worm.

  12. Making the Most of Omics for Symbiosis Research

    PubMed Central

    Chaston, J.; Douglas, A.E.

    2012-01-01

    Omics, including genomics, proteomics and metabolomics, enable us to explain symbioses in terms of the underlying molecules and their interactions. The central task is to transform molecular catalogs of genes, metabolites etc. into a dynamic understanding of symbiosis function. We review four exemplars of omics studies that achieve this goal, through defined biological questions relating to metabolic integration and regulation of animal-microbial symbioses, the genetic autonomy of bacterial symbionts, and symbiotic protection of animal hosts from pathogens. As omic datasets become increasingly complex, computationally-sophisticated downstream analyses are essential to reveal interactions not evident to visual inspection of the data. We discuss two approaches, phylogenomics and transcriptional clustering, that can divide the primary output of omics studies – long lists of factors – into manageable subsets, and we describe how they have been applied to analyze large datasets and generate testable hypotheses. PMID:22983030

  13. Plant LysM proteins: modules mediating symbiosis and immunity.

    PubMed

    Gust, Andrea A; Willmann, Roland; Desaki, Yoshitake; Grabherr, Heini M; Nürnberger, Thorsten

    2012-08-01

    Microbial glycans, such as bacterial peptidoglycans, fungal chitin or rhizobacterial Nod factors (NFs), are important signatures for plant immune activation or for the establishment of beneficial symbioses. Plant lysin motif (LysM) domain proteins serve as modules mediating recognition of these different N-acetylglucosamine (GlcNAc)-containing ligands, suggesting that this class of proteins evolved from an ancient sensor for GlcNAc. During early plant evolution, these glycans probably served as immunogenic patterns activating LysM protein receptor-mediated plant immunity and stopping microbial infection. The biochemical potential of plant LysM proteins for sensing microbial GlcNAc-containing glycans has probably since favored the evolution of receptors facilitating microbial infection and symbiosis. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Getting at the "what" and the "how" in symbiosis.

    PubMed

    Newton, Irene L G

    2017-02-01

    Symbioses are ubiquitous and have had a tremendous impact on the evolution of life on the planet. Indeed, endosymbiosis lead to the generation of the first eukaryotic cell and from that point onwards, eukaryotes have interacted with the other domains of life, sometimes forming persistent and necessary relationships that span generations. However, because the majority of hosts and symbionts are not easily manipulated, the intricate details of these symbioses, an understanding of the molecular underpinnings of these interactions, have not been elucidated. It is difficult to ask questions about the details of a host-microbe symbiosis if either member cannot be cultured, genetically manipulated, or even housed in a laboratory. Several technological advances in recent years may address these difficulties, making it easier for researchers to ask mechanistic questions in symbiotic systems. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  15. Long-distance transport of signals during symbiosis

    PubMed Central

    Xie, Zhi-Ping; Illana, Antonio

    2011-01-01

    Legumes enter nodule symbioses with nitrogen-fixing bacteria (rhizobia), whereas most flowering plants establish symbiotic associations with arbuscular mycorrhizal (AM) fungi. Once first steps of symbiosis are initiated, nodule formation and mycorrhization in legumes is negatively controlled by a shoot-derived inhibitor (SDI), a phenomenon termed autoregulation. According to current views, autoregulation of nodulation and mycorrhization in legumes is regulated in a similar way. CLE peptides induced in response to rhizobial nodulation signals (Nod factors) have been proposed to represent the ascending long-distance signals to the shoot. Although not proven yet, these CLE peptides are likely perceived by leucine-rich repeat (LRR) autoregulation receptor kinases in the shoot. Autoregulation of mycorrhization in non-legumes is reminiscent to the phenomenon of “systemic acquired resistance” in plant-pathogen interactions. PMID:21455020

  16. Bacterial Molecular Signals in the Sinorhizobium fredii-Soybean Symbiosis

    PubMed Central

    López-Baena, Francisco J.; Ruiz-Sainz, José E.; Rodríguez-Carvajal, Miguel A.; Vinardell, José M.

    2016-01-01

    Sinorhizobium (Ensifer) fredii (S. fredii) is a rhizobial species exhibiting a remarkably broad nodulation host-range. Thus, S. fredii is able to effectively nodulate dozens of different legumes, including plants forming determinate nodules, such as the important crops soybean and cowpea, and plants forming indeterminate nodules, such as Glycyrrhiza uralensis and pigeon-pea. This capacity of adaptation to different symbioses makes the study of the molecular signals produced by S. fredii strains of increasing interest since it allows the analysis of their symbiotic role in different types of nodule. In this review, we analyze in depth different S. fredii molecules that act as signals in symbiosis, including nodulation factors, different surface polysaccharides (exopolysaccharides, lipopolysaccharides, cyclic glucans, and K-antigen capsular polysaccharides), and effectors delivered to the interior of the host cells through a symbiotic type 3 secretion system. PMID:27213334

  17. Species specificity of symbiosis and secondary metabolism in ascidians

    PubMed Central

    Tianero, Ma Diarey B; Kwan, Jason C; Wyche, Thomas P; Presson, Angela P; Koch, Michael; Barrows, Louis R; Bugni, Tim S; Schmidt, Eric W

    2015-01-01

    Ascidians contain abundant, diverse secondary metabolites, which are thought to serve a defensive role and which have been applied to drug discovery. It is known that bacteria in symbiosis with ascidians produce several of these metabolites, but very little is known about factors governing these ‘chemical symbioses'. To examine this phenomenon across a wide geographical and species scale, we performed bacterial and chemical analyses of 32 different ascidians, mostly from the didemnid family from Florida, Southern California and a broad expanse of the tropical Pacific Ocean. Bacterial diversity analysis showed that ascidian microbiomes are highly diverse, and this diversity does not correlate with geographical location or latitude. Within a subset of species, ascidian microbiomes are also stable over time (R=−0.037, P-value=0.499). Ascidian microbiomes and metabolomes contain species-specific and location-specific components. Location-specific bacteria are found in low abundance in the ascidians and mostly represent strains that are widespread. Location-specific metabolites consist largely of lipids, which may reflect differences in water temperature. By contrast, species-specific bacteria are mostly abundant sequenced components of the microbiomes and include secondary metabolite producers as major components. Species-specific chemicals are dominated by secondary metabolites. Together with previous analyses that focused on single ascidian species or symbiont type, these results reveal fundamental properties of secondary metabolic symbiosis. Different ascidian species have established associations with many different bacterial symbionts, including those known to produce toxic chemicals. This implies a strong selection for this property and the independent origin of secondary metabolite-based associations in different ascidian species. The analysis here streamlines the connection of secondary metabolite to producing bacterium, enabling further biological and

  18. Lichen Symbiosis: Nature's High Yielding Machines for Induced Hydrogen Production

    PubMed Central

    Papazi, Aikaterini; Kastanaki, Elizabeth; Pirintsos, Stergios; Kotzabasis, Kiriakos

    2015-01-01

    Hydrogen is a promising future energy source. Although the ability of green algae to produce hydrogen has long been recognized (since 1939) and several biotechnological applications have been attempted, the greatest obstacle, being the O2-sensitivity of the hydrogenase enzyme, has not yet been overcome. In the present contribution, 75 years after the first report on algal hydrogen production, taking advantage of a natural mechanism of oxygen balance, we demonstrate high hydrogen yields by lichens. Lichens have been selected as the ideal organisms in nature for hydrogen production, since they consist of a mycobiont and a photobiont in symbiosis. It has been hypothesized that the mycobiont’s and photobiont’s consumption of oxygen (increase of COX and AOX proteins of mitochondrial respiratory pathways and PTOX protein of chrolorespiration) establishes the required anoxic conditions for the activation of the phycobiont’s hydrogenase in a closed system. Our results clearly supported the above hypothesis, showing that lichens have the ability to activate appropriate bioenergetic pathways depending on the specific incubation conditions. Under light conditions, they successfully use the PSII-dependent and the PSII-independent pathways (decrease of D1 protein and parallel increase of PSaA protein) to transfer electrons to hydrogenase, while under dark conditions, lichens use the PFOR enzyme and the dark fermentative pathway to supply electrons to hydrogenase. These advantages of lichen symbiosis in combination with their ability to survive in extreme environments (while in a dry state) constitute them as unique and valuable hydrogen producing natural factories and pave the way for future biotechnological applications. PMID:25826211

  19. Origin of Chemical Diversity in Prochloron-Tunicate Symbiosis

    PubMed Central

    Lin, Zhenjian; Torres, Joshua P.; Tianero, M. Diarey; Kwan, Jason C.

    2016-01-01

    ABSTRACT Diversity-generating metabolism leads to the evolution of many different chemicals in living organisms. Here, by examining a marine symbiosis, we provide a precise evolutionary model of how nature generates a family of novel chemicals, the cyanobactins. We show that tunicates and their symbiotic Prochloron cyanobacteria share congruent phylogenies, indicating that Prochloron phylogeny is related to host phylogeny and not to external habitat or geography. We observe that Prochloron exchanges discrete functional genetic modules for cyanobactin secondary metabolite biosynthesis in an otherwise conserved genetic background. The module exchange leads to gain or loss of discrete chemical functional groups. Because the underlying enzymes exhibit broad substrate tolerance, discrete exchange of substrates and enzymes between Prochloron strains leads to the rapid generation of chemical novelty. These results have implications in choosing biochemical pathways and enzymes for engineered or combinatorial biosynthesis. IMPORTANCE While most biosynthetic pathways lead to one or a few products, a subset of pathways are diversity generating and are capable of producing thousands to millions of derivatives. This property is highly useful in biotechnology since it enables biochemical or synthetic biological methods to create desired chemicals. A fundamental question has been how nature itself creates this chemical diversity. Here, by examining the symbiosis between coral reef animals and bacteria, we describe the genetic basis of chemical variation with unprecedented precision. New compounds from the cyanobactin family are created by either varying the substrate or importing needed enzymatic functions from other organisms or via both mechanisms. This natural process matches successful laboratory strategies to engineer the biosynthesis of new chemicals and teaches a new strategy to direct biosynthesis. PMID:27037119

  20. Lichen symbiosis: nature's high yielding machines for induced hydrogen production.

    PubMed

    Papazi, Aikaterini; Kastanaki, Elizabeth; Pirintsos, Stergios; Kotzabasis, Kiriakos

    2015-01-01

    Hydrogen is a promising future energy source. Although the ability of green algae to produce hydrogen has long been recognized (since 1939) and several biotechnological applications have been attempted, the greatest obstacle, being the O2-sensitivity of the hydrogenase enzyme, has not yet been overcome. In the present contribution, 75 years after the first report on algal hydrogen production, taking advantage of a natural mechanism of oxygen balance, we demonstrate high hydrogen yields by lichens. Lichens have been selected as the ideal organisms in nature for hydrogen production, since they consist of a mycobiont and a photobiont in symbiosis. It has been hypothesized that the mycobiont's and photobiont's consumption of oxygen (increase of COX and AOX proteins of mitochondrial respiratory pathways and PTOX protein of chrolorespiration) establishes the required anoxic conditions for the activation of the phycobiont's hydrogenase in a closed system. Our results clearly supported the above hypothesis, showing that lichens have the ability to activate appropriate bioenergetic pathways depending on the specific incubation conditions. Under light conditions, they successfully use the PSII-dependent and the PSII-independent pathways (decrease of D1 protein and parallel increase of PSaA protein) to transfer electrons to hydrogenase, while under dark conditions, lichens use the PFOR enzyme and the dark fermentative pathway to supply electrons to hydrogenase. These advantages of lichen symbiosis in combination with their ability to survive in extreme environments (while in a dry state) constitute them as unique and valuable hydrogen producing natural factories and pave the way for future biotechnological applications.

  1. [Mycoplasma hominis symbiosis and Trichomonas vaginalis metronidazole resistance].

    PubMed

    Wang, Pin-Jia; Xie, Cheng-Bin

    2012-06-30

    To investigate the relation of Mycoplasma hominis symbiosis and the resistance of Trichomonas vaginalis to metronidazole. From November 2010 to July 2011, 160 isolates of T. vaginalis were collected from the genital tract secretion of gynecological out-patients at the Sichuan Provincial Hospital for Women and Children. The minimum lethal concentration (MLC) to metronidazole of these isolates was determined by an in vitro sensitivity assay with different concentration gradients of metronidazole (from 1 to 1 024 microg/ml), and M. hominis DNA in T. vaginalis was detected by polymerase chain reaction (PCR) technique with specific 16S rRNA primers. After clearance of M. hominis from the parasites by 32 microg/ml doxycycline, MLC was determined and compared with that before clearance. MLC of metronidazole in T. vaginalis ranged from 1 to 256 microg/ml, with 61.3% isolates (98/160) ranging from 1 to 8 microg/ml, 26.3% isolates (42/160) ranging from 16 to 32 microg/ml, and 12.5% isolates (20/160) ranging from 64 to 256 microg/ml. 61 isolates were PCR positive for M. hominis DNA in the 160 isolates of T. vaginalis. The M. hominis DNA positive rate was significantly higher in the T. vaginalis isolates with higher MLC than those isolates with lower MLC (P<0.01). However, when M. hominis was cleared by doxycycline from 8 isolates among the 61 ones, no change was observed in sensitivity of the isolates to metronidazole. M. hominis symbiosis might be associated with the metronidazole-resistance of T. vaginalis. However, it needs direct evidence.

  2. Trans-generational specificity within a cnidarian-algal symbiosis

    NASA Astrophysics Data System (ADS)

    Poland, D. M.; Coffroth, M. A.

    2017-03-01

    Ocean warming and other anthropogenic stresses threaten the symbiosis between tropical reef cnidarians and their dinoflagellate endosymbionts ( Symbiodinium). Offspring of many cnidarians acquire their algal symbionts from the environment, and such flexibility could allow corals to respond to environmental changes between generations. To investigate the effect of both habitat and host genotype on symbiont acquisition, we transplanted aposymbiotic offspring of the common Caribbean octocoral Briareum asbestinum to (1) an environmentally different habitat that lacked B. asbestinum and (2) an environmentally similar habitat where local adults harbored Symbiodinium phylotypes that differed from parental colonies. Symbiont acquisition and establishment of symbioses over time was followed using a within-clade DNA marker (23S chloroplast rDNA) and a within-phylotype marker (unique alleles at a single microsatellite locus). Early in the symbiosis, B. asbestinum juveniles harbored multiple symbiont phylotypes, regardless of source (parent or site). However, with time ( 4 yr), offspring established symbioses with the symbiont phylotype dominant in the parental colonies, regardless of transplant location. Within-phylotype analyses of the symbionts revealed a similar pattern, with offspring acquiring the allelic variant common in symbionts in the parental population regardless of the environment in which the offspring was reared. These data suggest that in this host species, host-symbiont specificity is a genetically determined trait. If this level of specificity is widespread among other symbiotic cnidarians, many cnidarian-algal symbioses may not be able to respond to rapid, climate change-associated environmental changes by means of between-generation switching of symbionts.

  3. Origin of Chemical Diversity in Prochloron-Tunicate Symbiosis.

    PubMed

    Lin, Zhenjian; Torres, Joshua P; Tianero, M Diarey; Kwan, Jason C; Schmidt, Eric W

    2016-06-15

    Diversity-generating metabolism leads to the evolution of many different chemicals in living organisms. Here, by examining a marine symbiosis, we provide a precise evolutionary model of how nature generates a family of novel chemicals, the cyanobactins. We show that tunicates and their symbiotic Prochloron cyanobacteria share congruent phylogenies, indicating that Prochloron phylogeny is related to host phylogeny and not to external habitat or geography. We observe that Prochloron exchanges discrete functional genetic modules for cyanobactin secondary metabolite biosynthesis in an otherwise conserved genetic background. The module exchange leads to gain or loss of discrete chemical functional groups. Because the underlying enzymes exhibit broad substrate tolerance, discrete exchange of substrates and enzymes between Prochloron strains leads to the rapid generation of chemical novelty. These results have implications in choosing biochemical pathways and enzymes for engineered or combinatorial biosynthesis. While most biosynthetic pathways lead to one or a few products, a subset of pathways are diversity generating and are capable of producing thousands to millions of derivatives. This property is highly useful in biotechnology since it enables biochemical or synthetic biological methods to create desired chemicals. A fundamental question has been how nature itself creates this chemical diversity. Here, by examining the symbiosis between coral reef animals and bacteria, we describe the genetic basis of chemical variation with unprecedented precision. New compounds from the cyanobactin family are created by either varying the substrate or importing needed enzymatic functions from other organisms or via both mechanisms. This natural process matches successful laboratory strategies to engineer the biosynthesis of new chemicals and teaches a new strategy to direct biosynthesis. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  4. Species specificity of symbiosis and secondary metabolism in ascidians.

    PubMed

    Tianero, Ma Diarey B; Kwan, Jason C; Wyche, Thomas P; Presson, Angela P; Koch, Michael; Barrows, Louis R; Bugni, Tim S; Schmidt, Eric W

    2015-03-01

    Ascidians contain abundant, diverse secondary metabolites, which are thought to serve a defensive role and which have been applied to drug discovery. It is known that bacteria in symbiosis with ascidians produce several of these metabolites, but very little is known about factors governing these 'chemical symbioses'. To examine this phenomenon across a wide geographical and species scale, we performed bacterial and chemical analyses of 32 different ascidians, mostly from the didemnid family from Florida, Southern California and a broad expanse of the tropical Pacific Ocean. Bacterial diversity analysis showed that ascidian microbiomes are highly diverse, and this diversity does not correlate with geographical location or latitude. Within a subset of species, ascidian microbiomes are also stable over time (R=-0.037, P-value=0.499). Ascidian microbiomes and metabolomes contain species-specific and location-specific components. Location-specific bacteria are found in low abundance in the ascidians and mostly represent strains that are widespread. Location-specific metabolites consist largely of lipids, which may reflect differences in water temperature. By contrast, species-specific bacteria are mostly abundant sequenced components of the microbiomes and include secondary metabolite producers as major components. Species-specific chemicals are dominated by secondary metabolites. Together with previous analyses that focused on single ascidian species or symbiont type, these results reveal fundamental properties of secondary metabolic symbiosis. Different ascidian species have established associations with many different bacterial symbionts, including those known to produce toxic chemicals. This implies a strong selection for this property and the independent origin of secondary metabolite-based associations in different ascidian species. The analysis here streamlines the connection of secondary metabolite to producing bacterium, enabling further biological and

  5. Unfolding the secrets of coral-algal symbiosis.

    PubMed

    Rosic, Nedeljka; Ling, Edmund Yew Siang; Chan, Chon-Kit Kenneth; Lee, Hong Ching; Kaniewska, Paulina; Edwards, David; Dove, Sophie; Hoegh-Guldberg, Ove

    2015-03-17

    Dinoflagellates from the genus Symbiodinium form a mutualistic symbiotic relationship with reef-building corals. Here we applied massively parallel Illumina sequencing to assess genetic similarity and diversity among four phylogenetically diverse dinoflagellate clades (A, B, C and D) that are commonly associated with corals. We obtained more than 30,000 predicted genes for each Symbiodinium clade, with a majority of the aligned transcripts corresponding to sequence data sets of symbiotic dinoflagellates and <2% of sequences having bacterial or other foreign origin. We report 1053 genes, orthologous among four Symbiodinium clades, that share a high level of sequence identity to known proteins from the SwissProt (SP) database. Approximately 80% of the transcripts aligning to the 1053 SP genes were unique to Symbiodinium species and did not align to other dinoflagellates and unrelated eukaryotic transcriptomes/genomes. Six pathways were common to all four Symbiodinium clades including the phosphatidylinositol signaling system and inositol phosphate metabolism pathways. The list of Symbiodinium transcripts common to all four clades included conserved genes such as heat shock proteins (Hsp70 and Hsp90), calmodulin, actin and tubulin, several ribosomal, photosynthetic and cytochrome genes and chloroplast-based heme-containing cytochrome P450, involved in the biosynthesis of xanthophylls. Antioxidant genes, which are important in stress responses, were also preserved, as were a number of calcium-dependent and calcium/calmodulin-dependent protein kinases that may play a role in the establishment of symbiosis. Our findings disclose new knowledge about the genetic uniqueness of symbiotic dinoflagellates and provide a list of homologous genes important for the foundation of coral-algal symbiosis.

  6. Big Data Approaches To Coral-Microbe Symbiosis

    NASA Astrophysics Data System (ADS)

    Zaneveld, J.; Pollock, F. J.; McMinds, R.; Smith, S.; Payet, J.; Hanna, B.; Welsh, R.; Foster, A.; Ohdera, A.; Shantz, A. A.; Burkepile, D. E.; Maynard, J. A.; Medina, M.; Vega Thurber, R.

    2016-02-01

    Coral reefs face increasing challenges worldwide, threatened by overfishing and nutrient pollution, which drive growth of algal competitors of corals, and periods of extreme temperature, which drive mass coral bleaching. I will discuss two projects that examine how coral's complex relationships with microorganisms affect the response of coral colonies and coral species to environmental challenge. Microbiological studies have documented key roles for coral's microbial symbionts in energy harvest and defense against pathogens. However, the evolutionary history of corals and their microbes is little studied. As part of the Global Coral Microbiome Project, we are characterizing bacterial, archaeal, fungal, and Symbiodinium diversity across >1400 DNA samples from all major groups of corals, collected from 15 locations worldwide. This collection will allow us to ask how coral- microbe associations evolved over evolutionary time, and to determine whether microbial symbiosis helps predict the relative vulnerability of certain coral species to environmental stress. In the second project, we experimentally characterized how the long-term effects of human impacts such as overfishing and nutrient pollution influence coral-microbe symbiosis. We conducted a three-year field experiment in the Florida Keys applying nutrient pollution or simulated overfishing to reef plots, and traced the effects on reef communities, coral microbiomes, and coral health. The results show that extremes of temperature and algal competition destabilize coral microbiomes, increasing pathogen blooms, coral disease, and coral death. Surprisingly, these local stressors interacted strongly with thermal stress: the greatest microbiome disruption, and >80% of coral mortality happened in the hottest periods. Thus, overfishing and nutrient pollution may interact with increased climate-driven episodes of sub-bleaching thermal stress to increase coral mortality by disrupt reef communities down to microbial scales.

  7. Unfolding the secrets of coral–algal symbiosis

    PubMed Central

    Rosic, Nedeljka; Ling, Edmund Yew Siang; Chan, Chon-Kit Kenneth; Lee, Hong Ching; Kaniewska, Paulina; Edwards, David; Dove, Sophie; Hoegh-Guldberg, Ove

    2015-01-01

    Dinoflagellates from the genus Symbiodinium form a mutualistic symbiotic relationship with reef-building corals. Here we applied massively parallel Illumina sequencing to assess genetic similarity and diversity among four phylogenetically diverse dinoflagellate clades (A, B, C and D) that are commonly associated with corals. We obtained more than 30 000 predicted genes for each Symbiodinium clade, with a majority of the aligned transcripts corresponding to sequence data sets of symbiotic dinoflagellates and <2% of sequences having bacterial or other foreign origin. We report 1053 genes, orthologous among four Symbiodinium clades, that share a high level of sequence identity to known proteins from the SwissProt (SP) database. Approximately 80% of the transcripts aligning to the 1053 SP genes were unique to Symbiodinium species and did not align to other dinoflagellates and unrelated eukaryotic transcriptomes/genomes. Six pathways were common to all four Symbiodinium clades including the phosphatidylinositol signaling system and inositol phosphate metabolism pathways. The list of Symbiodinium transcripts common to all four clades included conserved genes such as heat shock proteins (Hsp70 and Hsp90), calmodulin, actin and tubulin, several ribosomal, photosynthetic and cytochrome genes and chloroplast-based heme-containing cytochrome P450, involved in the biosynthesis of xanthophylls. Antioxidant genes, which are important in stress responses, were also preserved, as were a number of calcium-dependent and calcium/calmodulin-dependent protein kinases that may play a role in the establishment of symbiosis. Our findings disclose new knowledge about the genetic uniqueness of symbiotic dinoflagellates and provide a list of homologous genes important for the foundation of coral–algal symbiosis. PMID:25343511

  8. 7 CFR 1217.22 - Promotion.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOFTWOOD LUMBER RESEARCH, PROMOTION, CONSUMER EDUCATION AND INDUSTRY INFORMATION ORDER Softwood Lumber Research, Promotion, Consumer Education, and Industry Information Order Definitions § 1217.22 Promotion. Promotion means any action...

  9. 7 CFR 1217.22 - Promotion.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOFTWOOD LUMBER RESEARCH, PROMOTION, CONSUMER EDUCATION AND INDUSTRY INFORMATION ORDER Softwood Lumber Research, Promotion, Consumer Education, and Industry Information Order Definitions § 1217.22 Promotion. Promotion means any action...

  10. 7 CFR 1217.22 - Promotion.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOFTWOOD LUMBER RESEARCH, PROMOTION, CONSUMER EDUCATION AND INDUSTRY INFORMATION ORDER Softwood Lumber Research, Promotion, Consumer Education, and Industry Information Order Definitions § 1217.22 Promotion. Promotion means any action...

  11. Using technology to promote science as a basic subject for literacy: A precollege/college/industry/government collaboration

    SciTech Connect

    Redmond, B.L.; Saturnelli, A.M.

    1994-12-31

    Our goal is to ensure that All students have the opportunity to learn science, and it is being accomplished through a unique working model program that: (1) changes the way that teaching and learning take place; (2) incorporates the advanced technology of microscopy directly into the K-12 curriculum; and (3) develops R & D teacher specialists. We conducted three in-service science courses, a Summer Science Microscopy Camp, and a staff development program (the latter funded by a NYS Education Department grant) in which science professors, industrial engineers and scientists interacted with teachers and students to explore the world using high technology. This year, all 5th and 7th graders in the district (200 students) and about 1,000 high school science students are having experiences as active researchers, solving real-life, multi-step problems using all levels of microscopy, including scanning tunneling. Students develop a chronological portfolio, using multimedia formats. Our 1993 Summer Microscopy Camp attendance record was 98%, compared to the typical 75% for other programs.

  12. Pharmaceutical Industry Off-label Promotion and Self-regulation: A Document Analysis of Off-label Promotion Rulings by the United Kingdom Prescription Medicines Code of Practice Authority 2003–2012

    PubMed Central

    Vilhelmsson, Andreas; Davis, Courtney; Mulinari, Shai

    2016-01-01

    Background European Union law prohibits companies from marketing drugs off-label. In the United Kingdom—as in some other European countries, but unlike the United States—industry self-regulatory bodies are tasked with supervising compliance with marketing rules. The objectives of this study were to (1) characterize off-label promotion rulings in the UK compared to the whistleblower-initiated cases in the US and (2) shed light on the UK self-regulatory mechanism for detecting, deterring, and sanctioning off-label promotion. Methods and Findings We conducted structured reviews of rulings by the UK self-regulatory authority, the Prescription Medicines Code of Practice Authority (PMCPA), between 2003 and 2012. There were 74 off-label promotion rulings involving 43 companies and 65 drugs. Nineteen companies were ruled in breach more than once, and ten companies were ruled in breach three or more times over the 10-y period. Drawing on a typology previously developed to analyse US whistleblower complaints, we coded and analysed the apparent strategic goals of each off-label marketing scheme and the practices consistent with those alleged goals. 50% of rulings cited efforts to expand drug use to unapproved indications, and 39% and 38% cited efforts to expand beyond approved disease entities and dosing strategies, respectively. The most frequently described promotional tactic was attempts to influence prescribers (n = 72, 97%), using print material (70/72, 97%), for example, advertisements (21/70, 30%). Although rulings cited prescribers as the prime target of off-label promotion, competing companies lodged the majority of complaints (prescriber: n = 16, 22%, versus companies: n = 42, 57%). Unlike US whistleblower complaints, few UK rulings described practices targeting consumers (n = 3, 4%), payers (n = 2, 3%), or company staff (n = 2, 3%). Eight UK rulings (11%) pertaining to six drugs described promotion of the same drug for the same off-label use as was alleged by

  13. Pharmaceutical Industry Off-label Promotion and Self-regulation: A Document Analysis of Off-label Promotion Rulings by the United Kingdom Prescription Medicines Code of Practice Authority 2003-2012.

    PubMed

    Vilhelmsson, Andreas; Davis, Courtney; Mulinari, Shai

    2016-01-01

    European Union law prohibits companies from marketing drugs off-label. In the United Kingdom--as in some other European countries, but unlike the United States--industry self-regulatory bodies are tasked with supervising compliance with marketing rules. The objectives of this study were to (1) characterize off-label promotion rulings in the UK compared to the whistleblower-initiated cases in the US and (2) shed light on the UK self-regulatory mechanism for detecting, deterring, and sanctioning off-label promotion. We conducted structured reviews of rulings by the UK self-regulatory authority, the Prescription Medicines Code of Practice Authority (PMCPA), between 2003 and 2012. There were 74 off-label promotion rulings involving 43 companies and 65 drugs. Nineteen companies were ruled in breach more than once, and ten companies were ruled in breach three or more times over the 10-y period. Drawing on a typology previously developed to analyse US whistleblower complaints, we coded and analysed the apparent strategic goals of each off-label marketing scheme and the practices consistent with those alleged goals. 50% of rulings cited efforts to expand drug use to unapproved indications, and 39% and 38% cited efforts to expand beyond approved disease entities and dosing strategies, respectively. The most frequently described promotional tactic was attempts to influence prescribers (n = 72, 97%), using print material (70/72, 97%), for example, advertisements (21/70, 30%). Although rulings cited prescribers as the prime target of off-label promotion, competing companies lodged the majority of complaints (prescriber: n = 16, 22%, versus companies: n = 42, 57%). Unlike US whistleblower complaints, few UK rulings described practices targeting consumers (n = 3, 4%), payers (n = 2, 3%), or company staff (n = 2, 3%). Eight UK rulings (11%) pertaining to six drugs described promotion of the same drug for the same off-label use as was alleged by whistleblowers in the US. However

  14. Media(ted) fabrications: how the science-media symbiosis helped 'sell' cord banking.

    PubMed

    Michelle, Carolyn

    2006-01-01

    This paper considers the problematic role of the science-media symbiosis in the dissemination of misleading and emotionally manipulative information regarding services offered by CordBank, New Zealand's only umbilical cord blood banking facility. As this case study illustrates, the growing reliance of health and science reporters on the knowledge capital of medical specialists, biogenetic researchers, and scientists potentially enhances the ability of 'expert' sources to set the agenda for media representations of emerging medical and scientific developments, and may undermine the editorial independence of journalists and editors, many of whom in this case failed to critically evaluate deeply problematic claims regarding the current and future benefits of cord banking. Heavy reliance on established media frames of anecdotal personalization and technoboosterism also reinforced a proscience journalistic culture in which claims by key sources were uncritically reiterated and amplified, with journalistic assessments of the value of cord banking emphasizing potential benefits for individual consumers. It is argued that use of these media frames potentially detracts from due consideration of the broader social, ethical, legal, and health implications of emerging biomedical developments, along with the professional, personal, and increasingly also financial interests at stake in their public promotion, given the growing commercialization of biogenetic technologies.

  15. Repeated replacement of an intrabacterial symbiont in the tripartite nested mealybug symbiosis

    PubMed Central

    Husnik, Filip; McCutcheon, John P.

    2016-01-01

    Stable endosymbiosis of a bacterium into a host cell promotes cellular and genomic complexity. The mealybug Planococcus citri has two bacterial endosymbionts with an unusual nested arrangement: the γ-proteobacterium Moranella endobia lives in the cytoplasm of the β-proteobacterium Tremblaya princeps. These two bacteria, along with genes horizontally transferred from other bacteria to the P. citri genome, encode gene sets that form an interdependent metabolic patchwork. Here, we test the stability of this three-way symbiosis by sequencing host and symbiont genomes for five diverse mealybug species and find marked fluidity over evolutionary time. Although Tremblaya is the result of a single infection in the ancestor of mealybugs, the γ-proteobacterial symbionts result from multiple replacements of inferred different ages from related but distinct bacterial lineages. Our data show that symbiont replacement can happen even in the most intricate symbiotic arrangements and that preexisting horizontally transferred genes can remain stable on genomes in the face of extensive symbiont turnover. PMID:27573819

  16. Vibrio fischeri flavohemoglobin protects against nitric oxide during initiation of the squid-Vibrio symbiosis

    PubMed Central

    Wang, Yanling; Dunn, Anne K.; Wilneff, Jacqueline; McFall-Ngai, Margaret J.; Spiro, Stephen; Ruby, Edward G.

    2010-01-01

    Summary Nitric oxide (NO) is implicated in a wide range of biological processes, including innate immunity against pathogens, signal transduction, and protection against oxidative stress. However, its possible roles in beneficial host-microbe associations are less well recognized. During the early stages of the squid-vibrio symbiosis, the bacterial symbiont Vibrio fischeri encounters host-derived NO, which has been hypothesized to serve as specificity determinant. We demonstrate here that the flavohemoglobin, Hmp, of V. fischeri protects against NO, both in culture and during colonization of the squid host. Transcriptional analyses indicate that hmp expression is highly responsive to NO, principally through the repressor, NsrR. Hmp protects V. fischeri from NO inhibition of aerobic respiration, and removes NO under both oxic and anoxic conditions. A Δhmp mutant of V. fischeri initiates squid colonization less effectively than wild type, but is rescued by the presence of an NO synthase inhibitor. The hmp promoter is activated during the initial stage of colonization, during which the Δhmp strain fails to form normal-sized aggregates of colonizing cells. Taken together, these results suggest that the sensing of host-derived NO by NsrR, and the subsequent removal of NO by Hmp, influence aggregate size and, thereby, V. fischeri colonization efficiency. PMID:20815823

  17. Symbiosis theory-directed green synthesis of silver nanoparticles and their application in infected wound healing

    PubMed Central

    Wen, Lu; Zeng, Pei; Zhang, Liping; Huang, Wenli; Wang, Hui; Chen, Gang

    2016-01-01

    In this study, silver nanoparticles (AgNPs) were synthesized for the first time using an antibacterial endophytic fungus of Chinese medicinal herb Orchidantha chinensis, which has anti-inflammatory and antimicrobial activities. The AgNPs were analyzed by various characterization techniques to reveal their morphology, chemical composition, and stability. Also, the relationship between Chinese medicinal herbs, endophytic fungi, and the property of AgNPs was investigated for the first time. Interestingly, an experiment performed in this study revealed the proteins produced by the endophytic fungus to be capped on the nanoparticles, which led to an increase in the stability of spherical and polydispersed AgNPs with low aggregation for over 6 months. More importantly, further study demonstrated that the AgNPs possessed superior antibacterial activity and effectively promoted wound healing. Altogether, the biosynthesis of active AgNPs using the endophytic fungus from Chinese medicinal herb based on the symbiosis theory is simple, eco-friendly, and promising. PMID:27358563

  18. Vibrio fischeri flavohaemoglobin protects against nitric oxide during initiation of the squid-Vibrio symbiosis.

    PubMed

    Wang, Yanling; Dunn, Anne K; Wilneff, Jacqueline; McFall-Ngai, Margaret J; Spiro, Stephen; Ruby, Edward G

    2010-11-01

    Nitric oxide (NO) is implicated in a wide range of biological processes, including innate immunity against pathogens, signal transduction and protection against oxidative stress. However, its possible roles in beneficial host-microbe associations are less well recognized. During the early stages of the squid-vibrio symbiosis, the bacterial symbiont Vibrio fischeri encounters host-derived NO, which has been hypothesized to serve as a specificity determinant. We demonstrate here that the flavohaemoglobin, Hmp, of V. fischeri protects against NO, both in culture and during colonization of the squid host. Transcriptional analyses indicate that hmp expression is highly responsive to NO, principally through the repressor, NsrR. Hmp protects V. fischeri from NO inhibition of aerobic respiration, and removes NO under both oxic and anoxic conditions. A Δhmp mutant of V. fischeri initiates squid colonization less effectively than wild type, but is rescued by the presence of an NO synthase inhibitor. The hmp promoter is activated during the initial stage of colonization, during which the Δhmp strain fails to form normal-sized aggregates of colonizing cells. Taken together, these results suggest that the sensing of host-derived NO by NsrR, and the subsequent removal of NO by Hmp, influence aggregate size and, thereby, V. fischeri colonization efficiency. © 2010 Blackwell Publishing Ltd.

  19. Arbuscular mycorrhiza Symbiosis Induces a Major Transcriptional Reprogramming of the Potato SWEET Sugar Transporter Family

    PubMed Central

    Manck-Götzenberger, Jasmin; Requena, Natalia

    2016-01-01

    Biotrophic microbes feeding on plants must obtain carbon from their hosts without killing the cells. The symbiotic Arbuscular mycorrhizal (AM) fungi colonizing plant roots do so by inducing major transcriptional changes in the host that ultimately also reprogram the whole carbon partitioning of the plant. AM fungi obtain carbohydrates from the root cortex apoplast, in particular from the periarbuscular space that surrounds arbuscules. However, the mechanisms by which cortical cells export sugars into the apoplast for fungal nutrition are unknown. Recently a novel type of sugar transporter, the SWEET, able to perform not only uptake but also efflux from cells was identified. Plant SWEETs have been shown to be involved in the feeding of pathogenic microbes and are, therefore, good candidates to play a similar role in symbiotic associations. Here we have carried out the first phylogenetic and expression analyses of the potato SWEET family and investigated its role during mycorrhiza symbiosis. The potato genome contains 35 SWEETs that cluster into the same four clades defined in Arabidopsis. Colonization of potato roots by the AM fungus Rhizophagus irregularis imposes major transcriptional rewiring of the SWEET family involving, only in roots, changes in 22 of the 35 members. None of the SWEETs showed mycorrhiza-exclusive induction and most of the 12 induced genes belong to the putative hexose transporters of clade I and II, while only two are putative sucrose transporters from clade III. In contrast, most of the repressed transcripts (10) corresponded to clade III SWEETs. Promoter-reporter assays for three of the induced genes, each from one cluster, showed re-localization of expression to arbuscule-containing cells, supporting a role for SWEETs in the supply of sugars at biotrophic interfaces. The complex transcriptional regulation of SWEETs in roots in response to AM fungal colonization supports a model in which symplastic sucrose in cortical cells could be cleaved

  20. Arbuscular mycorrhiza Symbiosis Induces a Major Transcriptional Reprogramming of the Potato SWEET Sugar Transporter Family.

    PubMed

    Manck-Götzenberger, Jasmin; Requena, Natalia

    2016-01-01

    Biotrophic microbes feeding on plants must obtain carbon from their hosts without killing the cells. The symbiotic Arbuscular mycorrhizal (AM) fungi colonizing plant roots do so by inducing major transcriptional changes in the host that ultimately also reprogram the whole carbon partitioning of the plant. AM fungi obtain carbohydrates from the root cortex apoplast, in particular from the periarbuscular space that surrounds arbuscules. However, the mechanisms by which cortical cells export sugars into the apoplast for fungal nutrition are unknown. Recently a novel type of sugar transporter, the SWEET, able to perform not only uptake but also efflux from cells was identified. Plant SWEETs have been shown to be involved in the feeding of pathogenic microbes and are, therefore, good candidates to play a similar role in symbiotic associations. Here we have carried out the first phylogenetic and expression analyses of the potato SWEET family and investigated its role during mycorrhiza symbiosis. The potato genome contains 35 SWEETs that cluster into the same four clades defined in Arabidopsis. Colonization of potato roots by the AM fungus Rhizophagus irregularis imposes major transcriptional rewiring of the SWEET family involving, only in roots, changes in 22 of the 35 members. None of the SWEETs showed mycorrhiza-exclusive induction and most of the 12 induced genes belong to the putative hexose transporters of clade I and II, while only two are putative sucrose transporters from clade III. In contrast, most of the repressed transcripts (10) corresponded to clade III SWEETs. Promoter-reporter assays for three of the induced genes, each from one cluster, showed re-localization of expression to arbuscule-containing cells, supporting a role for SWEETs in the supply of sugars at biotrophic interfaces. The complex transcriptional regulation of SWEETs in roots in response to AM fungal colonization supports a model in which symplastic sucrose in cortical cells could be cleaved

  1. Landau and Lifshitz' formulation of Le Chatelier's principle: an insight into symbiosis?

    PubMed

    Halabi, T

    2013-12-01

    A correspondence allows application of Landau and Lifshitz' formulation of Le Chatelier's principle from statistical physics to a simple 2-D model of biological symbiosis. The insight: symbionts stabilize the occupation of narrow peaks on fitness landscape.

  2. The Laccaria and Tuber Genomes Reveal Unique Signatures of Mycorrhizal Symbiosis Evolution (2010 JGI User Meeting)

    SciTech Connect

    Knapp, Steve

    2010-03-24

    Francis Martin from the French agricultural research institute INRA talks on how "The Laccaria and Tuber genomes reveal unique signatures of mycorrhizal symbiosis evolution" on March 24, 2010 at the 5th Annual DOE JGI User Meeting

  3. LysM-type mycorrhizal receptor recruited for rhizobium symbiosis in nonlegume Parasponia.

    PubMed

    Op den Camp, Rik; Streng, Arend; De Mita, Stéphane; Cao, Qingqin; Polone, Elisa; Liu, Wei; Ammiraju, Jetty S S; Kudrna, Dave; Wing, Rod; Untergasser, Andreas; Bisseling, Ton; Geurts, René

    2011-02-18

    Rhizobium-root nodule symbiosis is generally considered to be unique for legumes. However, there is one exception, and that is Parasponia. In this nonlegume, the rhizobial nodule symbiosis evolved independently and is, as in legumes, induced by rhizobium Nod factors. We used Parasponia andersonii to identify genetic constraints underlying evolution of Nod factor signaling. Part of the signaling cascade, downstream of Nod factor perception, has been recruited from the more-ancient arbuscular endomycorrhizal symbiosis. However, legume Nod factor receptors that activate this common signaling pathway are not essential for arbuscular endomycorrhizae. Here, we show that in Parasponia a single Nod factor-like receptor is indispensable for both symbiotic interactions. Therefore, we conclude that the Nod factor perception mechanism also is recruited from the widespread endomycorrhizal symbiosis.

  4. Development of symbiosis-specific genes as biomarkers for the early detection of cnidarian-algal symbiosis breakdown.

    PubMed

    Mitchelmore, Carys L; Schwarz, Jodi A; Weis, Virginia M

    2002-01-01

    Coral bleaching, i.e. the loss of dinoflagellate symbionts from cnidarian hosts, is occurring globally at increasing rates, scales, and severity. The significance of these bleaching events to the health of coral reef ecosystems is extreme, as bleached corals exhibit high mortality, reduced fecundity and productivity and increased susceptibility to disease. This decreased coral fitness leads to reef degradation and ultimately to the breakdown of the coral reef ecosystem. To date there has been little work describing the application of biomarkers to assess coral health. The most commonly applied biomarker is, in fact, the bleaching event itself. We are interested in developing early warning biomarkers that can detect coral stress before bleaching occurs. Recently, several genes that are likely to function in regulating interactions between cnidarians and their symbionts have been characterized, using the temperate sea anemone Anthopleura elegantissima as a model species. One "symbiosis gene" identified from the host genome, sym32, is expressed as a function of anemone symbiotic-state, where sym32 expression is higher in symbiotic cf. aposymbiotic (symbiont-free) anemones. Real-time quantitative RT-PCR suggested that the level of sym32 expression was correlated with the abundance of algae in the host. Furthermore, laboratory exposures of anemones to low levels of cadmium (0, 20, 100 microg(-1) CdCl2; 14 days), which caused no change in algal cell numbers, resulted in a down-regulation of sym32 compared to controls, indicating that sym32 expression may serve as a new sensitive early warning biomarker of cnidarian-algal symbiosis breakdown.

  5. Origin and Evolution of Nitrogen Fixation Genes on Symbiosis Islands and Plasmid in Bradyrhizobium.

    PubMed

    Okubo, Takashi; Piromyou, Pongdet; Tittabutr, Panlada; Teaumroong, Neung; Minamisawa, Kiwamu

    2016-09-29

    The nitrogen fixation (nif) genes of nodule-forming Bradyrhizobium strains are generally located on symbiosis islands or symbiosis plasmids, suggesting that these genes have been transferred laterally. The nif genes of rhizobial and non-rhizobial Bradyrhizobium strains were compared in order to infer the evolutionary histories of nif genes. Based on all codon positions, the phylogenetic tree of concatenated nifD and nifK sequences showed that nifDK on symbiosis islands formed a different clade from nifDK on non-symbiotic loci (located outside of symbiosis islands and plasmids) with elongated branches; however, these genes were located in close proximity, when only the 1st and 2nd codon positions were analyzed. The guanine (G) and cytosine (C) content of the 3rd codon position of nifDK on symbiosis islands was lower than that on non-symbiotic loci. These results suggest that nif genes on symbiosis islands were derived from the non-symbiotic loci of Bradyrhizobium or closely related strains and have evolved toward a lower GC content with a higher substitution rate than the ancestral state. Meanwhile, nifDK on symbiosis plasmids clustered with nifDK on non-symbiotic loci in the tree representing all codon positions, and the GC content of symbiotic and non-symbiotic loci were similar. These results suggest that nif genes on symbiosis plasmids were derived from the non-symbiotic loci of Bradyrhizobium and have evolved with a similar evolutionary pattern and rate as the ancestral state.

  6. Origin and Evolution of Nitrogen Fixation Genes on Symbiosis Islands and Plasmid in Bradyrhizobium

    PubMed Central

    Okubo, Takashi; Piromyou, Pongdet; Tittabutr, Panlada; Teaumroong, Neung; Minamisawa, Kiwamu

    2016-01-01

    The nitrogen fixation (nif) genes of nodule-forming Bradyrhizobium strains are generally located on symbiosis islands or symbiosis plasmids, suggesting that these genes have been transferred laterally. The nif genes of rhizobial and non-rhizobial Bradyrhizobium strains were compared in order to infer the evolutionary histories of nif genes. Based on all codon positions, the phylogenetic tree of concatenated nifD and nifK sequences showed that nifDK on symbiosis islands formed a different clade from nifDK on non-symbiotic loci (located outside of symbiosis islands and plasmids) with elongated branches; however, these genes were located in close proximity, when only the 1st and 2nd codon positions were analyzed. The guanine (G) and cytosine (C) content of the 3rd codon position of nifDK on symbiosis islands was lower than that on non-symbiotic loci. These results suggest that nif genes on symbiosis islands were derived from the non-symbiotic loci of Bradyrhizobium or closely related strains and have evolved toward a lower GC content with a higher substitution rate than the ancestral state. Meanwhile, nifDK on symbiosis plasmids clustered with nifDK on non-symbiotic loci in the tree representing all codon positions, and the GC content of symbiotic and non-symbiotic loci were similar. These results suggest that nif genes on symbiosis plasmids were derived from the non-symbiotic loci of Bradyrhizobium and have evolved with a similar evolutionary pattern and rate as the ancestral state. PMID:27431195

  7. The engine of the reef: photobiology of the coral–algal symbiosis

    PubMed Central

    Roth, Melissa S.

    2014-01-01

    Coral reef ecosystems thrive in tropical oligotrophic oceans because of the relationship between corals and endosymbiotic dinoflagellate algae called Symbiodinium. Symbiodinium convert sunlight and carbon dioxide into organic carbon and oxygen to fuel coral growth and calcification, creating habitat for these diverse and productive ecosystems. Light is thus a key regulating factor shaping the productivity, physiology, and ecology of the coral holobiont. Similar to all oxygenic photoautotrophs, Symbiodinium must safely harvest sunlight for photosynthesis and dissipate excess energy to prevent oxidative stress. Oxidative stress is caused by environmental stressors such as those associated with global climate change, and ultimately leads to breakdown of the coral–algal symbiosis known as coral bleaching. Recently, large-scale coral bleaching events have become pervasive and frequent threatening and endangering coral reefs. Because the coral–algal symbiosis is the biological engine producing the reef, the future of coral reef ecosystems depends on the ecophysiology of the symbiosis. This review examines the photobiology of the coral–algal symbiosis with particular focus on the photophysiological responses and timescales of corals and Symbiodinium. Additionally, this review summarizes the light environment and its dynamics, the vulnerability of the symbiosis to oxidative stress, the abiotic and biotic factors influencing photosynthesis, the diversity of the coral–algal symbiosis, and recent advances in the field. Studies integrating physiology with the developing “omics” fields will provide new insights into the coral–algal symbiosis. Greater physiological and ecological understanding of the coral–algal symbiosis is needed for protection and conservation of coral reefs. PMID:25202301

  8. Life cycle assessment-driven selection of industrial ecology strategies.

    PubMed

    Ardente, Fulvio; Cellura, Maurizio; Lo Brano, Valerio; Mistretta, Marina

    2010-01-01

    The paper presents an application of the Life-Cycle Assessment (LCA) to the planning and environmental management of an “eco-industrial cluster.” A feasibility study of industrial symbiosis in southern Italy is carried out, where interlinked companies share subproducts and scraps, services, structures, and plants to reduce the related environmental impact. In particular, the research focuses on new recycling solutions to create open recycling loops in which plastic subproducts and scraps are transferred to external production systems. The main environmental benefits are the reduction of resource depletion, air emissions, and landfilled wastes. The proposed strategies are also economically viable and they suggest cost abatement for the involved companies. This research shows the need for a multidisciplinary approach to data processing and to complexity managing of the investigated systems. In this context, life-cycle thinking is required to be promoted throughout the economy, as well to be as a part of all decisions on products and other criteria such as functionality, health, and safety. The Life-Cycle Assessment approach can be assumed as a methodology for influencing decision makers to make sustainable choices.

  9. From defense to symbiosis: limited alterations in the kinase domain of LysM receptor-like kinases are crucial for evolution of legume-Rhizobium symbiosis.

    PubMed

    Nakagawa, Tomomi; Kaku, Hanae; Shimoda, Yoshikazu; Sugiyama, Akifumi; Shimamura, Masayuki; Takanashi, Kojiro; Yazaki, Kazufumi; Aoki, Toshio; Shibuya, Naoto; Kouchi, Hiroshi

    2011-01-01

    Nitrogen-fixing symbiosis between legumes and rhizobia is initiated by the recognition of rhizobial Nod factors (NFs) by host plants. NFs are diversely modified derivatives of chitin oligosaccharide, a fungal elicitor that induces defense responses in plants. Recent evidence has shown that both NFs and chitin elicitors are recognized by structurally related LysM receptor kinases. Transcriptome analyses of Lotus japonicus roots indicated that NFs not only activate symbiosis genes but also transiently activate defense-related genes through NF receptors. Conversely, chitin oligosaccharides were able to activate symbiosis genes independently of NF receptors. Analyses using chimeric genes consisting of the LysM receptor domain of a Lotus japonicus NF receptor, NFR1, and the kinase domain of an Arabidopsis chitin receptor, CERK1, demonstrated that substitution of a portion of the αEF helix in CERK1 with the amino acid sequence YAQ from the corresponding region of NFR1 enables L. japonicus nfr1 mutants to establish symbiosis with Mesorhizobium loti. We also showed that the kinase domains of two Lotus japonicus LysM receptor kinases, Lys6 and Lys7, which also possess the YAQ sequence, suppress the symbiotic defect of nfr1. These results strongly suggest that, in addition to adaptation of extracellular LysM domains to NFs, limited alterations in the kinase domain of chitin receptors have played a crucial role in shifting the intracellular signaling to symbiosis from defense responses, thus constituting one of the key genetic events in the evolution of root nodule symbiosis in legume plants. © 2010 The Authors. The Plant Journal © 2010 Blackwell Publishing Ltd.

  10. The environmental impact of growth-promoting compounds employed by the United States beef cattle industry: history, current knowledge, and future directions.

    PubMed

    Kolok, Alan S; Sellin, Marlo K

    2008-01-01

    The current state of knowledge regarding the environmental impact of growth-promoting compounds associated with the U.S. beef cattle industry is extensive in some areas but virtually nonexistent in others. The compounds administered to the cattle are quite well understood, as are bovine metabolism and excretion. If the sex and age of the cattle on the feedlot are known, the metabolites excreted by the cattle should be predictable with a great deal of accuracy. The fate, transport, and biological effects of growth-promoting compounds are just beginning to be studied. Most of the research conducted on the fate and transport of growth-promoting compounds has focused on 17beta-E2; however, much of this research was not conducted using feedlot runoff or manure. Studies are needed that focus specifically on manures and runoff from experimental or commercial feedlots. To date, the degree to which growth-promoting compounds are released from feedlots in a bioavailable form remains a point of speculation. The environmental fate and transport of TBA, P, and MGA have not been well studied. Comparisons between the fate and transport of T and 17beta-E2, however, make it clear that compounds with similar structure may behave very differently once released into the environment. Considering that 17beta-E2 is a naturally occurring estrogen and that TBA is a nonaromatizable androgen, it is not surprising that these compounds directly impact the reproductive physiology of fishes. The effects of these two compounds have been well documented, as has been described here; however, the effects of P and MGA exposures have gone largely uninvestigated. This is a serious critical gap in our knowledge base because progestogins play an important role in sex steroid synthesis and reproduction. Clearly, additional research on the consequences of exposures to P and MGA is warranted. The majority of research investigating the effects of 17beta-E2 and TBA metabolites on fish has been conducted in

  11. Carbon availability triggers fungal nitrogen uptake and transport in arbuscular mycorrhizal symbiosis.

    PubMed

    Fellbaum, Carl R; Gachomo, Emma W; Beesetty, Yugandhar; Choudhari, Sulbha; Strahan, Gary D; Pfeffer, Philip E; Kiers, E Toby; Bücking, Heike

    2012-02-14

    The arbuscular mycorrhizal (AM) symbiosis, formed between the majority of land plants and ubiquitous soil fungi of the phylum Glomeromycota, is responsible for massive nutrient transfer and global carbon sequestration. AM fungi take up nutrients from the soil and exchange them against photosynthetically fixed carbon (C) from the host. Recent studies have demonstrated that reciprocal reward strategies by plant and fungal partners guarantee a "fair trade" of phosphorus against C between partners [Kiers ET, et al. (2011) Science 333:880-882], but whether a similar reward mechanism also controls nitrogen (N) flux in the AM symbiosis is not known. Using mycorrhizal root organ cultures, we manipulated the C supply to the host and fungus and followed the uptake and transport of N sources in the AM symbiosis, the enzymatic activities of arginase and urease, and fungal gene expression in the extraradical and intraradical mycelium. We found that the C supply of the host plant triggers the uptake and transport of N in the symbiosis, and that the increase in N transport is orchestrated by changes in fungal gene expression. N transport in the symbiosis is stimulated only when the C is delivered by the host across the mycorrhizal interface, not when C is supplied directly to the fungal extraradical mycelium in the form of acetate. These findings support the importance of C flux from the root to the fungus as a key trigger for N uptake and transport and provide insight into the N transport regulation in the AM symbiosis.

  12. A Sinorhizobium meliloti RpoH-Regulated Gene Is Involved in Iron-Sulfur Protein Metabolism and Effective Plant Symbiosis under Intrinsic Iron Limitation.

    PubMed

    Sasaki, Shohei; Minamisawa, Kiwamu; Mitsui, Hisayuki

    2016-09-01

    In Sinorhizobium meliloti, RpoH-type sigma factors have a global impact on gene expression during heat shock and play an essential role in symbiosis with leguminous plants. Using mutational analysis of a set of genes showing highly RpoH-dependent expression during heat shock, we identified a gene indispensable for effective symbiosis. This gene, designated sufT, was located downstream of the sufBCDS homologs that specify the iron-sulfur (Fe/S) cluster assembly pathway. The identified transcription start site was preceded by an RpoH-dependent promoter consensus sequence. SufT was related to a conserved protein family of unknown molecular function, of which some members are involved in Fe/S cluster metabolism in diverse organisms. A sufT mutation decreased bacterial growth in both rich and minimal media, tolerance to stresses such as iron starvation, and activities of some Fe/S cluster-dependent enzymes. These results support the involvement of SufT in SUF (sulfur mobilization) system-mediated Fe/S protein metabolism. Furthermore, we isolated spontaneous pseudorevertants of the sufT mutant with partially recovered growth; each of them had a mutation in rirA This gene encodes a global iron regulator whose loss increases the intracellular iron content. Deletion of rirA in the original sufT mutant improved growth and restored Fe/S enzyme activities and effective symbiosis. These results suggest that enhanced iron availability compensates for the lack of SufT in the maintenance of Fe/S proteins. Although RpoH-type sigma factors of the RNA polymerase are present in diverse proteobacteria, their role as global regulators of protein homeostasis has been studied mainly in the enteric gammaproteobacterium Escherichia coli In the soil alphaproteobacterium Sinorhizobium meliloti, the rpoH mutations have a strong impact on symbiosis with leguminous plants. We found that sufT is a unique member of the S. meliloti RpoH regulon; sufT contributes to Fe/S protein metabolism and

  13. A Sinorhizobium meliloti RpoH-Regulated Gene Is Involved in Iron-Sulfur Protein Metabolism and Effective Plant Symbiosis under Intrinsic Iron Limitation

    PubMed Central

    Sasaki, Shohei; Minamisawa, Kiwamu

    2016-01-01

    ABSTRACT In Sinorhizobium meliloti, RpoH-type sigma factors have a global impact on gene expression during heat shock and play an essential role in symbiosis with leguminous plants. Using mutational analysis of a set of genes showing highly RpoH-dependent expression during heat shock, we identified a gene indispensable for effective symbiosis. This gene, designated sufT, was located downstream of the sufBCDS homologs that specify the iron-sulfur (Fe/S) cluster assembly pathway. The identified transcription start site was preceded by an RpoH-dependent promoter consensus sequence. SufT was related to a conserved protein family of unknown molecular function, of which some members are involved in Fe/S cluster metabolism in diverse organisms. A sufT mutation decreased bacterial growth in both rich and minimal media, tolerance to stresses such as iron starvation, and activities of some Fe/S cluster-dependent enzymes. These results support the involvement of SufT in SUF (sulfur mobilization) system-mediated Fe/S protein metabolism. Furthermore, we isolated spontaneous pseudorevertants of the sufT mutant with partially recovered growth; each of them had a mutation in rirA. This gene encodes a global iron regulator whose loss increases the intracellular iron content. Deletion of rirA in the original sufT mutant improved growth and restored Fe/S enzyme activities and effective symbiosis. These results suggest that enhanced iron availability compensates for the lack of SufT in the maintenance of Fe/S proteins. IMPORTANCE Although RpoH-type sigma factors of the RNA polymerase are present in diverse proteobacteria, their role as global regulators of protein homeostasis has been studied mainly in the enteric gammaproteobacterium Escherichia coli. In the soil alphaproteobacterium Sinorhizobium meliloti, the rpoH mutations have a strong impact on symbiosis with leguminous plants. We found that sufT is a unique member of the S. meliloti RpoH regulon; sufT contributes to Fe

  14. The characterization of six auxin-induced tomato GH3 genes uncovers a member, SlGH3.4, strongly responsive to arbuscular mycorrhizal symbiosis.

    PubMed

    Liao, Dehua; Chen, Xiao; Chen, Aiqun; Wang, Huimin; Liu, Jianjian; Liu, Junli; Gu, Mian; Sun, Shubin; Xu, Guohua

    2015-04-01

    In plants, the GH3 gene family is widely considered to be involved in a broad range of plant physiological processes, through modulation of hormonal homeostasis. Multiple GH3 genes have been functionally characterized in several plant species; however, to date, limited works to study the GH3 genes in tomato have been reported. Here, we characterize the expression and regulatory profiles of six tomato GH3 genes, SlGH3.2, SlGH3.3, SlGH3.4, SlGH3.7, SlGH3.9 and SlGH3.15, in response to different phytohormone applications and arbuscular mycorrhizal (AM) fungal colonization. All six GH3 genes showed inducible responses to external IAA, and three members were significantly up-regulated in response to AM symbiosis. In particular, SlGH3.4, the transcripts of which were barely detectable under normal growth conditions, was strongly activated in the IAA-treated and AM fungal-colonized roots. A comparison of the SlGH3.4 expression in wild-type plants and M161, a mutant with a defect in AM symbiosis, confirmed that SlGH3.4 expression is highly correlated to mycorrhizal colonization. Histochemical staining demonstrated that a 2,258 bp SlGH3.4 promoter fragment could drive β-glucuronidase (GUS) expression strongly in root tips, steles and cortical cells of IAA-treated roots, but predominantly in the fungal-colonized cells of mycorrhizal roots. A truncated 654 bp promoter failed to direct GUS expression in IAA-treated roots, but maintained the symbiosis-induced activity in mycorrhizal roots. In summary, our results suggest that a mycorrhizal signaling pathway that is at least partially independent of the auxin signaling pathway has evolved for the co-regulation of the auxin- and mycorrhiza-activated GH3 genes in plants.

  15. Iron: an essential micronutrient for the legume-rhizobium symbiosis

    PubMed Central

    Brear, Ella M.; Day, David A.; Smith, Penelope M. C.

    2013-01-01

    Legumes, which develop a symbiosis with nitrogen-fixing bacteria, have an increased demand for iron. Iron is required for the synthesis of iron-containing proteins in the host, including the highly abundant leghemoglobin, and in bacteroids for nitrogenase and cytochromes of the electron transport chain. Deficiencies in iron can affect initiation and development of the nodule. Within root cells, iron is chelated with organic acids such as citrate and nicotianamine and distributed to other parts of the plant. Transport to the nitrogen-fixing bacteroids in infected cells of nodules is more complicated. Formation of the symbiosis results in bacteroids internalized within root cortical cells of the legume where they are surrounded by a plant-derived membrane termed the symbiosome membrane (SM). This membrane forms an interface that regulates nutrient supply to the bacteroid. Consequently, iron must cross this membrane before being supplied to the bacteroid. Iron is transported across the SM as both ferric and ferrous iron. However, uptake of Fe(II) by both the symbiosome and bacteroid is faster than Fe(III) uptake. Members of more than one protein family may be responsible for Fe(II) transport across the SM. The only Fe(II) transporter in nodules characterized to date is GmDMT1 (Glycine max divalent metal transporter 1), which is located on the SM in soybean. Like the root plasma membrane, the SM has ferric iron reductase activity. The protein responsible has not been identified but is predicted to reduce ferric iron accumulated in the symbiosome space prior to uptake by the bacteroid. With the recent publication of a number of legume genomes including Medicago truncatula and G. max, a large number of additional candidate transport proteins have been identified. Members of the NRAMP (natural resistance-associated macrophage protein), YSL (yellow stripe-like), VIT (vacuolar iron transporter), and ZIP (Zrt-, Irt-like protein) transport families show enhanced expression in

  16. Global distribution and vertical patterns of a prymnesiophyte-cyanobacteria obligate symbiosis.

    PubMed

    Cabello, Ana M; Cornejo-Castillo, Francisco M; Raho, Nicolas; Blasco, Dolors; Vidal, Montserrat; Audic, Stéphane; de Vargas, Colomban; Latasa, Mikel; Acinas, Silvia G; Massana, Ramon

    2016-03-01

    A marine symbiosis has been recently discovered between prymnesiophyte species and the unicellular diazotrophic cyanobacterium UCYN-A. At least two different UCYN-A phylotypes exist, the clade UCYN-A1 in symbiosis with an uncultured small prymnesiophyte and the clade UCYN-A2 in symbiosis with the larger Braarudosphaera bigelowii. We targeted the prymnesiophyte-UCYN-A1 symbiosis by double CARD-FISH (catalyzed reporter deposition-fluorescence in situ hybridization) and analyzed its abundance in surface samples from the MALASPINA circumnavigation expedition. Our use of a specific probe for the prymnesiophyte partner allowed us to verify that this algal species virtually always carried the UCYN-A symbiont, indicating that the association was also obligate for the host. The prymnesiophyte-UCYN-A1 symbiosis was detected in all ocean basins, displaying a patchy distribution with abundances (up to 500 cells ml(-1)) that could vary orders of magnitude. Additional vertical profiles taken at the NE Atlantic showed that this symbiosis occupied the upper water column and disappeared towards the Deep Chlorophyll Maximum, where the biomass of the prymnesiophyte assemblage peaked. Moreover, sequences of both prymnesiophyte partners were searched within a large 18S rDNA metabarcoding data set from the Tara-Oceans expedition around the world. This sequence-based analysis supported the patchy distribution of the UCYN-A1 host observed by CARD-FISH and highlighted an unexpected homogeneous distribution (at low relative abundance) of B. bigelowii in the open ocean. Our results demonstrate that partners are always in symbiosis in nature and show contrasted ecological patterns of the two related lineages.

  17. Global distribution and vertical patterns of a prymnesiophyte–cyanobacteria obligate symbiosis

    PubMed Central

    Cabello, Ana M; Cornejo-Castillo, Francisco M; Raho, Nicolas; Blasco, Dolors; Vidal, Montserrat; Audic, Stéphane; de Vargas, Colomban; Latasa, Mikel; Acinas, Silvia G; Massana, Ramon

    2016-01-01

    A marine symbiosis has been recently discovered between prymnesiophyte species and the unicellular diazotrophic cyanobacterium UCYN-A. At least two different UCYN-A phylotypes exist, the clade UCYN-A1 in symbiosis with an uncultured small prymnesiophyte and the clade UCYN-A2 in symbiosis with the larger Braarudosphaera bigelowii. We targeted the prymnesiophyte–UCYN-A1 symbiosis by double CARD-FISH (catalyzed reporter deposition-fluorescence in situ hybridization) and analyzed its abundance in surface samples from the MALASPINA circumnavigation expedition. Our use of a specific probe for the prymnesiophyte partner allowed us to verify that this algal species virtually always carried the UCYN-A symbiont, indicating that the association was also obligate for the host. The prymnesiophyte–UCYN-A1 symbiosis was detected in all ocean basins, displaying a patchy distribution with abundances (up to 500 cells ml−1) that could vary orders of magnitude. Additional vertical profiles taken at the NE Atlantic showed that this symbiosis occupied the upper water column and disappeared towards the Deep Chlorophyll Maximum, where the biomass of the prymnesiophyte assemblage peaked. Moreover, sequences of both prymnesiophyte partners were searched within a large 18S rDNA metabarcoding data set from the Tara-Oceans expedition around the world. This sequence-based analysis supported the patchy distribution of the UCYN-A1 host observed by CARD-FISH and highlighted an unexpected homogeneous distribution (at low relative abundance) of B. bigelowii in the open ocean. Our results demonstrate that partners are always in symbiosis in nature and show contrasted ecological patterns of the two related lineages. PMID:26405830

  18. Algal ancestor of land plants was preadapted for symbiosis.

    PubMed

    Delaux, Pierre-Marc; Radhakrishnan, Guru V; Jayaraman, Dhileepkumar; Cheema, Jitender; Malbreil, Mathilde; Volkening, Jeremy D; Sekimoto, Hiroyuki; Nishiyama, Tomoaki; Melkonian, Michael; Pokorny, Lisa; Rothfels, Carl J; Sederoff, Heike Winter; Stevenson, Dennis W; Surek, Barbara; Zhang, Yong; Sussman, Michael R; Dunand, Christophe; Morris, Richard J; Roux, Christophe; Wong, Gane Ka-Shu; Oldroyd, Giles E D; Ané, Jean-Michel

    2015-10-27

    Colonization of land by plants was a major transition on Earth, but the developmental and genetic innovations required for this transition remain unknown. Physiological studies and the fossil record strongly suggest that the ability of the first land plants to form symbiotic associations with beneficial fungi was one of these critical innovations. In angiosperms, genes required for the perception and transduction of diffusible fungal signals for root colonization and for nutrient exchange have been characterized. However, the origin of these genes and their potential correlation with land colonization remain elusive. A comprehensive phylogenetic analysis of 259 transcriptomes and 10 green algal and basal land plant genomes, coupled with the characterization of the evolutionary path leading to the appearance of a key regulator, a calcium- and calmodulin-dependent protein kinase, showed that the symbiotic signaling pathway predated the first land plants. In contrast, downstream genes required for root colonization and their specific expression pattern probably appeared subsequent to the colonization of land. We conclude that the most recent common ancestor of extant land plants and green algae was preadapted for symbiotic associations. Subsequent improvement of this precursor stage in early land plants through rounds of gene duplication led to the acquisition of additional pathways and the ability to form a fully functional arbuscular mycorrhizal symbiosis.

  19. Symbiosis lost: imperfect vertical transmission of fungal endophytes in grasses.

    PubMed

    Afkhami, Michelle E; Rudgers, Jennifer A

    2008-09-01

    Vertically transmitted symbionts associate with some of the most ecologically dominant species on Earth, and their fixation has led to major evolutionary transitions (e.g., the development of mitochondria). Theory predicts that exclusive vertical transmission should favor mutualism and generate high frequencies of symbiosis in host populations. However, host populations often support lower-than-expected symbiont frequencies. Imperfect transmission (i.e., symbiont is not transmitted to all offspring) can reduce symbiont frequency, but for most beneficial symbionts it is unknown whether vertical transmission can be imperfect or during which life-history stage the symbiont is lost. Using quantitative natural history surveys of fungal endophytes in grasses, we show that transmission was imperfect in at least one stage for all seven host species examined. Endophytes were lost at all possible stages: within adult plants, from adult tillers to seeds, and from seeds to seedlings. Despite this loss, uninfected seeds failed to germinate in some species, resulting in perfect transmission to seedlings. The type and degree of loss differed among host populations and species and between endophyte genera. Populations with lower endophyte frequencies had higher rates of loss. Our results indicate new directions for understanding cooperation and conflict in symbioses and suggest mechanisms for host sanctions against costly symbionts.

  20. Engineering plant-microbe symbiosis for rhizoremediation of heavy metals.

    PubMed

    Wu, Cindy H; Wood, Thomas K; Mulchandani, Ashok; Chen, Wilfred

    2006-02-01

    The use of plants for rehabilitation of heavy-metal-contaminated environments is an emerging area of interest because it provides an ecologically sound and safe method for restoration and remediation. Although a number of plant species are capable of hyperaccumulation of heavy metals, the technology is not applicable for remediating sites with multiple contaminants. A clever solution is to combine the advantages of microbe-plant symbiosis within the plant rhizosphere into an effective cleanup technology. We demonstrated that expression of a metal-binding peptide (EC20) in a rhizobacterium, Pseudomonas putida 06909, not only improved cadmium binding but also alleviated the cellular toxicity of cadmium. More importantly, inoculation of sunflower roots with the engineered rhizobacterium resulted in a marked decrease in cadmium phytotoxicity and a 40% increase in cadmium accumulation in the plant root. Owing to the significantly improved growth characteristics of both the rhizobacterium and plant, the use of EC20-expressing P. putida endowed with organic-degrading capabilities may be a promising strategy to remediate mixed organic-metal-contaminated sites.

  1. The Sinorhizobium meliloti stringent response affects multiple aspects of symbiosis.

    PubMed

    Wells, Derek H; Long, Sharon R

    2002-03-01

    Sinorhizobium meliloti and host legumes enter into a nitrogen-fixing, symbiotic relationship triggered by an exchange of signals between bacteria and plant. S. meliloti produces Nod factor, which elicits the formation of nodules on plant roots, and succinoglycan, an exopolysaccharide that allows for bacterial invasion and colonization of the host. The biosynthesis of these molecules is well defined, but the specific regulation of these compounds is not completely understood. Bacteria control complex regulatory networks by the production of ppGpp, the effector molecule of the stringent response, which induces physiological change in response to adverse growth conditions and can also control bacterial development and virulence. Through detailed analysis of an S. meliloti mutant incapable of producing ppGpp, we show that the stringent response is required for nodule formation and regulates the production of succinoglycan. Although it remains unknown whether these phenotypes are connected, we have isolated suppressor strains that restore both defects and potentially identify key downstream regulatory genes. These results indicate that the S. meliloti stringent response has roles in both succinoglycan production and nodule formation and, more importantly, that control of bacterial physiology in response to the plant and surrounding environment is critical to the establishment of a successful symbiosis.

  2. Widespread fitness alignment in the legume-rhizobium symbiosis.

    PubMed

    Friesen, Maren L

    2012-06-01

    Although 'cheaters' potentially destabilize the legume-rhizobium mutualism, we lack a comprehensive review of host-symbiont fitness correlations. Studies measuring rhizobium relative or absolute fitness and host benefit are surveyed. Mutant studies are tallied for evidence of pleiotropy; studies of natural strains are analyzed with meta-analysis. Of 80 rhizobium mutations, 19 decrease both partners' fitness, four increase both, two increase host fitness but decrease symbiont fitness and none increase symbiont fitness at the host's expense. The pooled correlation between rhizobium nodulation competitiveness and plant aboveground biomass is 0.65 across five experiments that compete natural strains against a reference, whereas, across 14 experiments that compete rhizobia against soil populations or each other, the pooled correlation is 0.24. Pooled correlations between aboveground biomass and nodule number and nodule biomass are 0.76 and 0.83. Positive correlations between legume and rhizobium fitness imply that most ineffective rhizobia are 'defective' rather than 'defectors'; this extends to natural variants, with only one significant fitness conflict. Most studies involve non-coevolved associations, indicating that fitness alignment is the default state. Rhizobium mutations that increase both host and symbiont fitness suggest that some plants maladaptively restrict symbiosis with novel strains.

  3. Microgravity effects on the legume/Rhizobium symbiosis

    NASA Astrophysics Data System (ADS)

    Urban, James E.

    1997-01-01

    Symbiotic nitrogen fixation is of critical importance to world agriculture and likely will be a critical part of life support systems developed for prolonged missions in space. Bacteroid formation, an essential step in an effective Dutch White Clover/Rhizobium leguminosarum bv trifolii symbiosis, is induced by succinic acid which is produced by the plant and which is bound and incorporated by the bacterium. Aspirin mimics succinate in its role as a bacteroid inducer and measures of aspirin binding mimiced measurements of succinate binding. In normal gravity (1×g), rhizobium bacteria immediately bound relatively high levels of aspirin (or succinate) in a readily reversible manner. Within a few seconds a portion of this initially bound aspirin became irreversibly bound. In the microgravity environment aboard the NASA 930 aircraft, rhizobia did not display the initial reversible binding of succinate, but did display a similar kinetic pattern of irreversible binding, and ultimately bound 32% more succinate (Acta Astronautica 36:129-133, 1995.) In normal gravity succinate treated cells stop dividing and swell to their maximum size (twice the normal cell volume) within a time equivalent to the time required for two normal cell doublings. Swelling in microgravity was tested in FPA and BPM sample holders aboard the space shuttle (USML-1, and STS-54, 57, and 60.) The behavior of cells in the two sample holders was similar, and swelling behavior of cells in microgravity was identical to behavior in normal gravity.

  4. Genetic diversity for mycorrhizal symbiosis and phosphate transporters in rice.

    PubMed

    Jeong, Kwanho; Mattes, Nicolas; Catausan, Sheryl; Chin, Joong Hyoun; Paszkowski, Uta; Heuer, Sigrid

    2015-11-01

    Phosphorus (P) is a major plant nutrient and developing crops with higher P-use efficiency is an important breeding goal. In this context we have conducted a comparative study of irrigated and rainfed rice varieties to assess genotypic differences in colonization with arbuscular mycorrhizal (AM) fungi and expression of different P transporter genes. Plants were grown in three different soil samples from a rice farm in the Philippines. The data show that AM symbiosis in all varieties was established after 4 weeks of growth under aerobic conditions and that, in soil derived from a rice paddy, natural AM populations recovered within 6 weeks. The analysis of AM marker genes (AM1, AM3, AM14) and P transporter genes for the direct Pi uptake (PT2, PT6) and AM-mediated pathway (PT11, PT13) were largely in agreement with the observed root AM colonization providing a useful tool for diversity studies. Interestingly, delayed AM colonization was observed in the aus-type rice varieties which might be due to their different root structure and might confer an advantage for weed competition in the field. The data further showed that P-starvation induced root growth and expression of the high-affinity P transporter PT6 was highest in the irrigated variety IR66 which also maintained grain yield under P-deficient field conditions.

  5. A novel type of thioredoxin dedicated to symbiosis in legumes.

    PubMed

    Alkhalfioui, Fatima; Renard, Michelle; Frendo, Pierre; Keichinger, Corinne; Meyer, Yves; Gelhaye, Eric; Hirasawa, Masakazu; Knaff, David B; Ritzenthaler, Christophe; Montrichard, Françoise

    2008-09-01

    Thioredoxins (Trxs) constitute a family of small proteins in plants. This family has been extensively characterized in Arabidopsis (Arabidopsis thaliana), which contains six different Trx types: f, m, x, and y in chloroplasts, o in mitochondria, and h mainly in cytosol. A detailed study of this family in the model legume Medicago truncatula, realized here, has established the existence of two isoforms that do not belong to any of the types previously described. As no possible orthologs were further found in either rice (Oryza sativa) or poplar (Populus spp.), these novel isoforms may be specific for legumes. Nevertheless, on the basis of protein sequence and gene structure, they are both related to Trxs m and probably have evolved from Trxs m after the divergence of the higher plant families. They have redox potential values similar to those of the classical Trxs, and one of them can act as a substrate for the M. truncatula NADP-Trx reductase A. However, they differ from classical Trxs in that they possess an atypical putative catalytic site and lack disulfide reductase activity with insulin. Another important feature is the presence in both proteins of an N-terminal extension containing a putative signal peptide that targets them to the endoplasmic reticulum, as demonstrated by their transient expression in fusion with the green fluorescent protein in M. truncatula or Nicotiana benthamiana leaves. According to their pattern of expression, these novel isoforms function specifically in symbiotic interactions in legumes. They were therefore given the name of Trxs s, s for symbiosis.

  6. The dawn of symbiosis between plants and fungi

    PubMed Central

    Bidartondo, Martin I.; Read, David J.; Trappe, James M.; Merckx, Vincent; Ligrone, Roberto; Duckett, Jeffrey G.

    2011-01-01

    The colonization of land by plants relied on fundamental biological innovations, among which was symbiosis with fungi to enhance nutrient uptake. Here we present evidence that several species representing the earliest groups of land plants are symbiotic with fungi of the Mucoromycotina. This finding brings up the possibility that terrestrialization was facilitated by these fungi rather than, as conventionally proposed, by members of the Glomeromycota. Since the 1970s it has been assumed, largely from the observation that vascular plant fossils of the early Devonian (400 Ma) show arbuscule-like structures, that fungi of the Glomeromycota were the earliest to form mycorrhizas, and evolutionary trees have, until now, placed Glomeromycota as the oldest known lineage of endomycorrhizal fungi. Our observation that Endogone-like fungi are widely associated with the earliest branching land plants, and give way to glomeromycotan fungi in later lineages, raises the new hypothesis that members of the Mucoromycotina rather than the Glomeromycota enabled the establishment and growth of early land colonists. PMID:21389014

  7. Paracatenula, an ancient symbiosis between thiotrophic Alphaproteobacteria and catenulid flatworms

    PubMed Central

    Gruber-Vodicka, Harald Ronald; Dirks, Ulrich; Leisch, Nikolaus; Stoecker, Kilian; Bulgheresi, Silvia; Heindl, Niels Robert; Horn, Matthias; Lott, Christian; Loy, Alexander; Wagner, Michael; Ott, Jörg

    2011-01-01

    Harnessing chemosynthetic symbionts is a recurring evolutionary strategy. Eukaryotes from six phyla as well as one archaeon have acquired chemoautotrophic sulfur-oxidizing bacteria. In contrast to this broad host diversity, known bacterial partners apparently belong to two classes of bacteria—the Gamma- and Epsilonproteobacteria. Here, we characterize the intracellular endosymbionts of the mouthless catenulid flatworm genus Paracatenula as chemoautotrophic sulfur-oxidizing Alphaproteobacteria. The symbionts of Paracatenula galateia are provisionally classified as “Candidatus Riegeria galateiae” based on 16S ribosomal RNA sequencing confirmed by fluorescence in situ hybridization together with functional gene and sulfur metabolite evidence. 16S rRNA gene phylogenetic analysis shows that all 16 Paracatenula species examined harbor host species-specific intracellular Candidatus Riegeria bacteria that form a monophyletic group within the order Rhodospirillales. Comparing host and symbiont phylogenies reveals strict cocladogenesis and points to vertical transmission of the symbionts. Between 33% and 50% of the body volume of the various worm species is composed of bacterial symbionts, by far the highest proportion among all known endosymbiotic associations between bacteria and metazoans. This symbiosis, which likely originated more than 500 Mya during the early evolution of flatworms, is the oldest known animal–chemoautotrophic bacteria association. The distant phylogenetic position of the symbionts compared with other mutualistic or parasitic Alphaproteobacteria promises to illuminate the common genetic predispositions that have allowed several members of this class to successfully colonize eukaryote cells. PMID:21709249

  8. Cyclophilin and the regulation of symbiosis in Aiptasia pallida.

    PubMed

    Perez, S; Weis, V

    2008-08-01

    The sea anemone Aiptasia pallida, symbiotic with intracellular dinoflagellates, expresses a peptydyl-prolyl cis-trans isomerase (PPIase) belonging to the conserved family of cytosolic cyclophilins (ApCypA). Protein extracts from A. pallida exhibited PPIase activity. Given the high degree of conservation of ApCypA and its known function in the cellular stress response, we hypothesized that it plays a similar role in the cnidarian-dinoflagellate symbiosis. To explore its role, we inhibited the activity of cyclophilin with cyclosporin A (CsA). CsA effectively inhibited the PPIase activity of protein extracts from symbiotic A. pallida. CsA also induced the dose-dependent release of symbiotic algae from host tissues (bleaching). Laser scanning confocal microscopy using superoxide and nitric oxide-sensitive fluorescent dyes on live specimens of A. pallida revealed that CsA strongly induced the production of these known mediators of bleaching. We tested whether the CsA-sensitive isomerase activity is important for maintaining the activity of the antioxidant enzyme superoxide dismutase (SOD). SOD activity of protein extracts was not affected by pre-incubation with CsA in vitro.

  9. Engineering Plant-Microbe Symbiosis for Rhizoremediation of Heavy Metals

    PubMed Central

    Wu, Cindy H.; Wood, Thomas K.; Mulchandani, Ashok; Chen, Wilfred

    2006-01-01

    The use of plants for rehabilitation of heavy-metal-contaminated environments is an emerging area of interest because it provides an ecologically sound and safe method for restoration and remediation. Although a number of plant species are capable of hyperaccumulation of heavy metals, the technology is not applicable for remediating sites with multiple contaminants. A clever solution is to combine the advantages of microbe-plant symbiosis within the plant rhizosphere into an effective cleanup technology. We demonstrated that expression of a metal-binding peptide (EC20) in a rhizobacterium, Pseudomonas putida 06909, not only improved cadmium binding but also alleviated the cellular toxicity of cadmium. More importantly, inoculation of sunflower roots with the engineered rhizobacterium resulted in a marked decrease in cadmium phytotoxicity and a 40% increase in cadmium accumulation in the plant root. Owing to the significantly improved growth characteristics of both the rhizobacterium and plant, the use of EC20-expressing P. putida endowed with organic-degrading capabilities may be a promising strategy to remediate mixed organic-metal-contaminated sites. PMID:16461658

  10. Synthetic biology approaches to engineering the nitrogen symbiosis in cereals.

    PubMed

    Rogers, Christian; Oldroyd, Giles E D

    2014-05-01

    Nitrogen is abundant in the earth's atmosphere but, unlike carbon, cannot be directly assimilated by plants. The limitation this places on plant productivity has been circumvented in contemporary agriculture through the production and application of chemical fertilizers. The chemical reduction of nitrogen for this purpose consumes large amounts of energy and the reactive nitrogen released into the environment as a result of fertilizer application leads to greenhouse gas emissions, as well as widespread eutrophication of aquatic ecosystems. The environmental impacts are intensified by injudicious use of fertilizers in many parts of the world. Simultaneously, limitations in the production and supply of chemical fertilizers in other regions are leading to low agricultural productivity and malnutrition. Nitrogen can be directly fixed from the atmosphere by some bacteria and Archaea, which possess the enzyme nitrogenase. Some plant species, most notably legumes, have evolved close symbiotic associations with nitrogen-fixing bacteria. Engineering cereal crops with the capability to fix their own nitrogen could one day address the problems created by the over- and under-use of nitrogen fertilizers in agriculture. This could be achieved either by expression of a functional nitrogenase enzyme in the cells of the cereal crop or through transferring the capability to form a symbiotic association with nitrogen-fixing bacteria. While potentially transformative, these biotechnological approaches are challenging; however, with recent advances in synthetic biology they are viable long-term goals. This review discusses the possibility of these biotechnological solutions to the nitrogen problem, focusing on engineering the nitrogen symbiosis in cereals.

  11. Trusted Autonomy and Cognitive Cyber Symbiosis: Open Challenges.

    PubMed

    Abbass, Hussein A; Petraki, Eleni; Merrick, Kathryn; Harvey, John; Barlow, Michael

    This paper considers two emerging interdisciplinary, but related topics that are likely to create tipping points in advancing the engineering and science areas. Trusted Autonomy (TA) is a field of research that focuses on understanding and designing the interaction space between two entities each of which exhibits a level of autonomy. These entities can be humans, machines, or a mix of the two. Cognitive Cyber Symbiosis (CoCyS) is a cloud that uses humans and machines for decision-making. In CoCyS, human-machine teams are viewed as a network with each node comprising humans (as computational machines) or computers. CoCyS focuses on the architecture and interface of a Trusted Autonomous System. This paper examines these two concepts and seeks to remove ambiguity by introducing formal definitions for these concepts. It then discusses open challenges for TA and CoCyS, that is, whether a team made of humans and machines can work in fluid, seamless harmony.

  12. Microbial fuel cells for robotics: energy autonomy through artificial symbiosis.

    PubMed

    Ieropoulos, Ioannis A; Greenman, John; Melhuish, Chris; Horsfield, Ian

    2012-06-01

    The development of the microbial fuel cell (MFC) technology has seen an enormous growth over the last hundred years since its inception by Potter in 1911. The technology has reached a level of maturity that it is now considered to be a field in its own right with a growing scientific community. The highest level of activity has been recorded over the last decade and it is perhaps considered commonplace that MFCs are primarily suitable for stationary, passive wastewater treatment applications. Sceptics have certainly not considered MFCs as serious contenders in the race for developing renewable energy technologies. Yet this is the only type of alternative system that can convert organic waste-widely distributed around the globe-directly into electricity, and therefore, the only technology that will allow artificial agents to autonomously operate in a plethora of environments. This Minireview describes the history and current state-of-the-art regarding MFCs in robotics and their vital role in artificial symbiosis and autonomy. Furthermore, the article demonstrates how pursuing practical robotic applications can provide insights of the core MFC technology in general.

  13. Paracatenula, an ancient symbiosis between thiotrophic Alphaproteobacteria and catenulid flatworms.

    PubMed

    Gruber-Vodicka, Harald Ronald; Dirks, Ulrich; Leisch, Nikolaus; Baranyi, Christian; Stoecker, Kilian; Bulgheresi, Silvia; Heindl, Niels Robert; Horn, Matthias; Lott, Christian; Loy, Alexander; Wagner, Michael; Ott, Jörg

    2011-07-19

    Harnessing chemosynthetic symbionts is a recurring evolutionary strategy. Eukaryotes from six phyla as well as one archaeon have acquired chemoautotrophic sulfur-oxidizing bacteria. In contrast to this broad host diversity, known bacterial partners apparently belong to two classes of bacteria--the Gamma- and Epsilonproteobacteria. Here, we characterize the intracellular endosymbionts of the mouthless catenulid flatworm genus Paracatenula as chemoautotrophic sulfur-oxidizing Alphaproteobacteria. The symbionts of Paracatenula galateia are provisionally classified as "Candidatus Riegeria galateiae" based on 16S ribosomal RNA sequencing confirmed by fluorescence in situ hybridization together with functional gene and sulfur metabolite evidence. 16S rRNA gene phylogenetic analysis shows that all 16 Paracatenula species examined harbor host species-specific intracellular Candidatus Riegeria bacteria that form a monophyletic group within the order Rhodospirillales. Comparing host and symbiont phylogenies reveals strict cocladogenesis and points to vertical transmission of the symbionts. Between 33% and 50% of the body volume of the various worm species is composed of bacterial symbionts, by far the highest proportion among all known endosymbiotic associations between bacteria and metazoans. This symbiosis, which likely originated more than 500 Mya during the early evolution of flatworms, is the oldest known animal-chemoautotrophic bacteria association. The distant phylogenetic position of the symbionts compared with other mutualistic or parasitic Alphaproteobacteria promises to illuminate the common genetic predispositions that have allowed several members of this class to successfully colonize eukaryote cells.

  14. Ant-plants and fungi: a new threeway symbiosis.

    PubMed

    Defossez, Emmanuel; Selosse, Marc-André; Dubois, Marie-Pierre; Mondolot, Laurence; Faccio, Antonella; Djieto-Lordon, Champlain; McKey, Doyle; Blatrix, Rumsaïs

    2009-06-01

    Symbioses between plants and fungi, fungi and ants, and ants and plants all play important roles in ecosystems. Symbioses involving all three partners appear to be rare. Here, we describe a novel tripartite symbiosis in which ants and a fungus inhabit domatia of an ant-plant, and present evidence that such interactions are widespread. We investigated 139 individuals of the African ant-plant Leonardoxa africana for occurrence of fungus. Behaviour of mutualist ants toward the fungus within domatia was observed using a video camera fitted with an endoscope. Fungi were identified by sequencing a fragment of their ribosomal DNA. Fungi were always present in domatia occupied by mutualist ants but never in domatia occupied by opportunistic or parasitic ants. Ants appear to favour the propagation, removal and maintenance of the fungus. Similar fungi were associated with other ant-plants in Cameroon. All belong to the ascomycete order Chaetothyriales; those from L. africana formed a monophyletic clade. These new plant-ant-fungus associations seem to be specific, as demonstrated within Leonardoxa and as suggested by fungal phyletic identities. Such tripartite associations are widespread in African ant-plants but have long been overlooked. Taking fungal partners into account will greatly enhance our understanding of symbiotic ant-plant mutualisms.

  15. The effects of SO sub 2 on Azolla - Anabaena symbiosis

    SciTech Connect

    Jaeseoun Hur; Wellburn, A.R. )

    1991-05-01

    Cultures of Azolla pinnata containing Anabaena were investigated as a sensitive and reproducible bioindicator of air pollution. Three equal doses of SO{sub 2} (week*ppb: 1*100, 2*50, 4*25) were applied to Azolla cultures growing in nitrogen-free medium in a specially-designed exposure system. Exposure to high concentrations of SO{sub 2} showed highly significant reductions in growth of the fern, while nitrogen fixation and heterocyst development were severely damaged. This was associated with a reduction of protein content in the SO{sub 2}-exposed ferns and again more significant at higher SO{sub 2} levels. There was a variation in the absolute amount of the individual pigments between SO{sub 2} doses and/or treatments which was related to the physiological development of the ferns throughout the fumigations. Moreover, the ratio of violaxanthin to antheraxanthin in the 100 ppb SO{sub 2}-treated ferns was significantly higher than that in the clean air-grown ferns. The results clearly demonstrate that SO{sub 2} has adverse effects on the symbiosis and suggest that this fern is a promising bioindicator of air pollution and a very good model to investigate the inter-relationships between photosynthesis, nitrogen fixation and air pollution stress.

  16. Crystal structure of a symbiosis-related lectin from octocoral.

    PubMed

    Kita, Akiko; Jimbo, Mitsuru; Sakai, Ryuichi; Morimoto, Yukio; Miki, Kunio

    2015-09-01

    D-Galactose-binding lectin from the octocoral, Sinularia lochmodes (SLL-2), distributes densely on the cell surface of microalgae, Symbiodinium sp., an endosymbiotic dinoflagellate of the coral, and is also shown to be a chemical cue that transforms dinoflagellate into a non-motile (coccoid) symbiotic state. SLL-2 binds with high affinity to the Forssman antigen (N-acetylgalactosamine(GalNAc)α1-3GalNAcβ1-3Galα1-4Galβ1-4Glc-ceramide), and the presence of Forssman antigen-like sugar on the surface of Symbiodinium CS-156 cells was previously confirmed. Here we report the crystal structures of SLL-2 and its GalNAc complex as the first crystal structures of a lectin involved in the symbiosis between coral and dinoflagellate. N-Linked sugar chains and a galactose derivative binding site common to H-type lectins were observed in each monomer of the hexameric SLL-2 crystal structure. In addition, unique sugar-binding site-like regions were identified at the top and bottom of the hexameric SLL-2 structure. These structural features suggest a possible binding mode between SLL-2 and Forssman antigen-like pentasaccharide.

  17. Cell and developmental biology of arbuscular mycorrhiza symbiosis.

    PubMed

    Gutjahr, Caroline; Parniske, Martin

    2013-01-01

    The default mineral nutrient acquisition strategy of land plants is the symbiosis with arbuscular mycorrhiza (AM) fungi. Research into the cell and developmental biology of AM revealed fascinating insights into the plasticity of plant cell development and of interorganismic communication. It is driven by the prospect of increased exploitation of AM benefits for sustainable agriculture. The plant cell developmental program for intracellular accommodation of AM fungi is activated by a genetically defined signaling pathway involving calcium spiking in the nucleus as second messenger. Calcium spiking is triggered by chitooligosaccharides released by AM fungi that are probably perceived via LysM domain receptor kinases. Fungal infection and calcium spiking are spatiotemporally coordinated, and only cells committed to accommodating the fungus undergo high-frequency spiking. Delivery of mineral nutrients by AM fungi occurs at tree-shaped hyphal structures, the arbuscules, in plant cortical cells. Nutrients are taken up at a plant-derived periarbuscular membrane, which surrounds fungal hyphae and carries a specific transporter composition that is of direct importance for symbiotic efficiency. An elegant study has unveiled a new and unexpected mechanism for specific protein localization to the periarbuscular membrane, which relies on the timing of gene expression to synchronize protein biosynthesis with a redirection of secretion. The control of AM development by phytohormones is currently subject to active investigation and has led to the rediscovery of strigolactones. Nearly all tested phytohormones regulate AM development, and major insights into the mechanisms of this regulation are expected in the near future.

  18. Algal ancestor of land plants was preadapted for symbiosis

    PubMed Central

    Delaux, Pierre-Marc; Radhakrishnan, Guru V.; Jayaraman, Dhileepkumar; Cheema, Jitender; Malbreil, Mathilde; Volkening, Jeremy D.; Sekimoto, Hiroyuki; Nishiyama, Tomoaki; Melkonian, Michael; Pokorny, Lisa; Rothfels, Carl J.; Sederoff, Heike Winter; Stevenson, Dennis W.; Surek, Barbara; Zhang, Yong; Sussman, Michael R.; Dunand, Christophe; Morris, Richard J.; Roux, Christophe; Wong, Gane Ka-Shu; Oldroyd, Giles E. D.; Ané, Jean-Michel

    2015-01-01

    Colonization of land by plants was a major transition on Earth, but the developmental and genetic innovations required for this transition remain unknown. Physiological studies and the fossil record strongly suggest that the ability of the first land plants to form symbiotic associations with beneficial fungi was one of these critical innovations. In angiosperms, genes required for the perception and transduction of diffusible fungal signals for root colonization and for nutrient exchange have been characterized. However, the origin of these genes and their potential correlation with land colonization remain elusive. A comprehensive phylogenetic analysis of 259 transcriptomes and 10 green algal and basal land plant genomes, coupled with the characterization of the evolutionary path leading to the appearance of a key regulator, a calcium- and calmodulin-dependent protein kinase, showed that the symbiotic signaling pathway predated the first land plants. In contrast, downstream genes required for root colonization and their specific expression pattern probably appeared subsequent to the colonization of land. We conclude that the most recent common ancestor of extant land plants and green algae was preadapted for symbiotic associations. Subsequent improvement of this precursor stage in early land plants through rounds of gene duplication led to the acquisition of additional pathways and the ability to form a fully functional arbuscular mycorrhizal symbiosis. PMID:26438870

  19. Genome-wide transcription start site mapping of Bradyrhizobium japonicum grown free-living or in symbiosis - a rich resource to identify new transcripts, proteins and to study gene regulation.

    PubMed

    Čuklina, Jelena; Hahn, Julia; Imakaev, Maxim; Omasits, Ulrich; Förstner, Konrad U; Ljubimov, Nikolay; Goebel, Melanie; Pessi, Gabriella; Fischer, Hans-Martin; Ahrens, Christian H; Gelfand, Mikhail S; Evguenieva-Hackenberg, Elena

    2016-04-23

    Differential RNA-sequencing (dRNA-seq) is indispensable for determination of primary transcriptomes. However, using dRNA-seq data to map transcriptional start sites (TSSs) and promoters genome-wide is a bioinformatics challenge. We performed dRNA-seq of Bradyrhizobium japonicum USDA 110, the nitrogen-fixing symbiont of soybean, and developed algorithms to map TSSs and promoters. A specialized machine learning procedure for TSS recognition allowed us to map 15,923 TSSs: 14,360 in free-living bacteria, 4329 in symbiosis with soybean and 2766 in both conditions. Further, we provide proteomic evidence for 4090 proteins, among them 107 proteins corresponding to new genes and 178 proteins with N-termini different from the existing annotation (72 and 109 of them with TSS support, respectively). Guided by proteomics evidence, previously identified TSSs and TSSs experimentally validated here, we assign a score threshold to flag 14 % of the mapped TSSs as a class of lower confidence. However, this class of lower confidence contains valid TSSs of low-abundant transcripts. Moreover, we developed a de novo algorithm to identify promoter motifs upstream of mapped TSSs, which is publicly available, and found motifs mainly used in symbiosis (similar to RpoN-dependent promoters) or under both conditions (similar to RpoD-dependent promoters). Mapped TSSs and putative promoters, proteomic evidence and updated gene annotation were combined into an annotation file. The genome-wide TSS and promoter maps along with the extended genome annotation of B. japonicum represent a valuable resource for future systems biology studies and for detailed analyses of individual non-coding transcripts and ORFs. Our data will also provide new insights into bacterial gene regulation during the agriculturally important symbiosis between rhizobia and legumes.

  20. DELLA proteins regulate expression of a subset of AM symbiosis-induced genes in Medicago truncatula.

    PubMed

    Floss, Daniela S; Lévesque-Tremblay, Véronique; Park, Hee-Jin; Harrison, Maria J

    2016-01-01

    The majority of the vascular flowering plants form symbiotic associations with fungi from the phylum Glomeromycota through which both partners gain access to nutrients, either mineral nutrients in the case of the plant, or carbon, in the case of the fungus. (1) The association develops in the roots and requires substantial remodeling of the root cortical cells where branched fungal hyphae, called arbuscules, are housed in a new membrane-bound apoplastic compartment. (2) Nutrient exchange between the symbionts occurs over this interface and its development and maintenance is critical for symbiosis. Previously, we showed that DELLA proteins, which are well known as repressors of gibberellic acid signaling, also regulate development of AM symbiosis and are necessary to enable arbuscule development. (3) Furthermore, constitutive overexpression of a dominant DELLA protein (della1-Δ18) is sufficient to induce transcripts of several AM symbiosis-induced genes, even in the absence of the fungal symbiont. (4) Here we further extend this approach and identify AM symbiosis genes that respond transcriptionally to constitutive expression of a dominant DELLA protein and also genes that do respond to this treatment. Additionally, we demonstrate that DELLAs interact with REQUIRED FOR ARBUSCULE DEVELOPMENT 1 (RAD1) which further extends our knowledge of GRAS factor complexes that have the potential to regulate gene expression during AM symbiosis.

  1. Rhizobium-legume symbiosis shares an exocytotic pathway required for arbuscule formation.

    PubMed

    Ivanov, Sergey; Fedorova, Elena E; Limpens, Erik; De Mita, Stephane; Genre, Andrea; Bonfante, Paola; Bisseling, Ton

    2012-05-22

    Endosymbiotic interactions are characterized by the formation of specialized membrane compartments, by the host in which the microbes are hosted, in an intracellular manner. Two well-studied examples, which are of major agricultural and ecological importance, are the widespread arbuscular mycorrhizal symbiosis and the Rhizobium-legume symbiosis. In both symbioses, the specialized host membrane that surrounds the microbes forms a symbiotic interface, which facilitates the exchange of, for example, nutrients in a controlled manner and, therefore, forms the heart of endosymbiosis. Despite their key importance, the molecular and cellular mechanisms underlying the formation of these membrane interfaces are largely unknown. Recent studies strongly suggest that the Rhizobium-legume symbiosis coopted a signaling pathway, including receptor, from the more ancient arbuscular mycorrhizal symbiosis to form a symbiotic interface. Here, we show that two highly homologous exocytotic vesicle-associated membrane proteins (VAMPs) are required for formation of the symbiotic membrane interface in both interactions. Silencing of these Medicago VAMP72 genes has a minor effect on nonsymbiotic plant development and nodule formation. However, it blocks symbiosome as well as arbuscule formation, whereas root colonization by the microbes is not affected. Identification of these VAMP72s as common symbiotic regulators in exocytotic vesicle trafficking suggests that the ancient exocytotic pathway forming the periarbuscular membrane compartment has also been coopted in the Rhizobium-legume symbiosis.

  2. DELLA proteins regulate expression of a subset of AM symbiosis-induced genes in Medicago truncatula

    PubMed Central

    Floss, Daniela S.; Lévesque-Tremblay, Véronique; Park, Hee-Jin; Harrison, Maria J.

    2016-01-01

    ABSTRACT The majority of the vascular flowering plants form symbiotic associations with fungi from the phylum Glomeromycota through which both partners gain access to nutrients, either mineral nutrients in the case of the plant, or carbon, in the case of the fungus.1 The association develops in the roots and requires substantial remodeling of the root cortical cells where branched fungal hyphae, called arbuscules, are housed in a new membrane-bound apoplastic compartment.2 Nutrient exchange between the symbionts occurs over this interface and its development and maintenance is critical for symbiosis. Previously, we showed that DELLA proteins, which are well known as repressors of gibberellic acid signaling, also regulate development of AM symbiosis and are necessary to enable arbuscule development.3 Furthermore, constitutive overexpression of a dominant DELLA protein (della1-Δ18) is sufficient to induce transcripts of several AM symbiosis-induced genes, even in the absence of the fungal symbiont.4 Here we further extend this approach and identify AM symbiosis genes that respond transcriptionally to constitutive expression of a dominant DELLA protein and also genes that do respond to this treatment. Additionally, we demonstrate that DELLAs interact with REQUIRED FOR ARBUSCULE DEVELOPMENT 1 (RAD1) which further extends our knowledge of GRAS factor complexes that have the potential to regulate gene expression during AM symbiosis. PMID:26984507

  3. Laser microdissection and its application to analyze gene expression in arbuscular mycorrhizal symbiosis.

    PubMed

    Gomez, S Karen; Harrison, Maria J

    2009-05-01

    Phosphorus is essential for plant growth, and in many soils phosphorus availability limits crop production. Most plants in natural ecosystems obtain phosphorus via a symbiotic partnership with arbuscular mycorrhizal (AM) fungi. While the significance of these associations is apparent, their molecular basis is poorly understood. Consequently, the potential to harness the mycorrhizal symbiosis to improve phosphorus nutrition in agriculture is not realized. Transcript profiling has recently been used to investigate gene expression changes that accompany development of the AM symbiosis. While these approaches have enabled the identification of AM-symbiosis-associated genes, they have generally involved the use of RNA from whole mycorrhizal roots. Laser microdissection techniques allow the dissection and capture of individual cells from a tissue. RNA can then be isolated from these samples and cell-type specific gene expression information can be obtained. This technology has been applied to obtain cells from plants and more recently to study plant-microbe interactions. The latter techniques, particularly those developed for root-microbe interactions, are of relevance to plant-parasitic weed research. Here, laser microdissection, its use in plant biology and in particular plant-microbe interactions are discussed. An overview of the AM symbiosis is then provided, with a focus on recent advances in understanding development of the arbuscule-cortical cell interface. Finally, the recent applications of laser microdissection for analyses of AM symbiosis are discussed.

  4. A Legume TOR Protein Kinase Regulates Rhizobium Symbiosis and Is Essential for Infection and Nodule Development.

    PubMed

    Nanjareddy, Kalpana; Blanco, Lourdes; Arthikala, Manoj-Kumar; Alvarado-Affantranger, Xóchitl; Quinto, Carmen; Sánchez, Federico; Lara, Miguel

    2016-11-01

    The target of rapamycin (TOR) protein kinase regulates metabolism, growth, and life span in yeast, animals, and plants in coordination with nutrient status and environmental conditions. The nutrient-dependent nature of TOR functionality makes this kinase a putative regulator of symbiotic associations involving nutrient acquisition. However, TOR's role in these processes remains to be understood. Here, we uncovered the role of TOR during the bean (Phaseolus vulgaris)-Rhizobium tropici (Rhizobium) symbiotic interaction. TOR was expressed in all tested bean tissues, with higher transcript levels in the root meristems and senesced nodules. We showed TOR promoter expression along the progressing infection thread and in the infected cells of mature nodules. Posttranscriptional gene silencing of TOR using RNA interference (RNAi) showed that this gene is involved in lateral root elongation and root cell organization and also alters the density, size, and number of root hairs. The suppression of TOR transcripts also affected infection thread progression and associated cortical cell divisions, resulting in a drastic reduction of nodule numbers. TOR-RNAi resulted in reduced reactive oxygen species accumulation and altered CyclinD1 and CyclinD3 expression, which are crucial factors for infection thread progression and nodule organogenesis. Enhanced expression of TOR-regulated ATG genes in TOR-RNAi roots suggested that TOR plays a role in the recognition of Rhizobium as a symbiont. Together, these data suggest that TOR plays a vital role in the establishment of root nodule symbiosis in the common bean. © 2016 American Society of Plant Biologists. All Rights Reserved.

  5. Lipo-Chitin Oligosaccharides, Plant Symbiosis Signalling Molecules That Modulate Mammalian Angiogenesis In Vitro

    PubMed Central

    Djordjevic, Michael A.; Bezos, Anna; Susanti; Marmuse, Laurence; Driguez, Hugues; Samain, Eric; Vauzeilles, Boris; Beau, Jean-Marie; Kordbacheh, Farzaneh; Rolfe, Barry G.; Schwörer, Ralf; Daines, Alison M.; Gresshoff, Peter M.; Parish, Christopher R.

    2014-01-01

    Lipochitin oligosaccharides (LCOs) are signaling molecules required by ecologically and agronomically important bacteria and fungi to establish symbioses with diverse land plants. In plants, oligo-chitins and LCOs can differentially interact with different lysin motif (LysM) receptors and affect innate immunity responses or symbiosis-related pathways. In animals, oligo-chitins also induce innate immunity and other physiological responses but LCO recognition has not been demonstrated. Here LCO and LCO-like compounds are shown to be biologically active in mammals in a structure dependent way through the modulation of angiogenesis, a tightly-regulated process involving the induction and growth of new blood vessels from existing vessels. The testing of 24 LCO, LCO-like or oligo-chitin compounds resulted in structure-dependent effects on angiogenesis in vitro leading to promotion, or inhibition or nil effects. Like plants, the mammalian LCO biological activity depended upon the presence and type of terminal substitutions. Un-substituted oligo-chitins of similar chain lengths were unable to modulate angiogenesis indicating that mammalian cells, like plant cells, can distinguish between LCOs and un-substituted oligo-chitins. The cellular mode-of-action of the biologically active LCOs in mammals was determined. The stimulation or inhibition of endothelial cell adhesion to vitronectin or fibronectin correlated with their pro- or anti-angiogenic activity. Importantly, novel and more easily synthesised LCO-like disaccharide molecules were also biologically active and de-acetylated chitobiose was shown to be the primary structural basis of recognition. Given this, simpler chitin disaccharides derivatives based on the structure of biologically active LCOs were synthesised and purified and these showed biological activity in mammalian cells. Since important chronic disease states are linked to either insufficient or excessive angiogenesis, LCO and LCO-like molecules may have the

  6. Stress tolerance in plants via habitat-adapted symbiosis

    USGS Publications Warehouse

    Rodriguez, R.J.; Henson, J.; Van Volkenburgh, E.; Hoy, M.; Wright, L.; Beckwith, F.; Kim, Y.-O.; Redman, R.S.

    2008-01-01

    We demonstrate that native grass species from coastal and geothermal habitats require symbiotic fungal endophytes for salt and heat tolerance, respectively. Symbiotically conferred stress tolerance is a habitat-specific phenomenon with geothermal endophytes conferring heat but not salt tolerance, and coastal endophytes conferring salt but not heat tolerance. The same fungal species isolated from plants in habitats devoid of salt or heat stress did not confer these stress tolerances. Moreover, fungal endophytes from agricultural crops conferred disease resistance and not salt or heat tolerance. We define habitat-specific, symbiotically-conferred stress tolerance as habitat-adapted symbiosis and hypothesize that it is responsible for the establishment of plants in high-stress habitats. The agricultural, coastal and geothermal plant endophytes also colonized tomato (a model eudicot) and conferred disease, salt and heat tolerance, respectively. In addition, the coastal plant endophyte colonized rice (a model monocot) and conferred salt tolerance. These endophytes have a broad host range encompassing both monocots and eudicots. Interestingly, the endophytes also conferred drought tolerance to plants regardless of the habitat of origin. Abiotic stress tolerance correlated either with a decrease in water consumption or reactive oxygen sensitivity/generation but not to increased osmolyte production. The ability of fungal endophytes to confer stress tolerance to plants may provide a novel strategy for mitigating the impacts of global climate change on agricultural and native plant communities.The ISME Journal (2008) 2, 404-416; doi:10.1038/ismej.2007.106; published online 7 February 2008. ?? 2008 International Society for Microbial Ecology All rights reserved.

  7. Shared Skeletal Support in a Coral-Hydroid Symbiosis

    PubMed Central

    Pantos, Olga; Hoegh-Guldberg, Ove

    2011-01-01

    Hydroids form symbiotic relationships with a range of invertebrate hosts. Where they live with colonial invertebrates such as corals or bryozoans the hydroids may benefit from the physical support and protection of their host's hard exoskeleton, but how they interact with them is unknown. Electron microscopy was used to investigate the physical interactions between the colonial hydroid Zanclea margaritae and its reef-building coral host Acropora muricata. The hydroid tissues extend below the coral tissue surface sitting in direct contact with the host's skeleton. Although this arrangement provides the hydroid with protective support, it also presents problems of potential interference with the coral's growth processes and exposes the hydroid to overgrowth and smothering. Desmocytes located within the epidermal layer of the hydroid's perisarc-free hydrorhizae fasten it to the coral skeleton. The large apical surface area of the desmocyte and high bifurcation of the distal end within the mesoglea, as well as the clustering of desmocytes suggests that a very strong attachment between the hydroid and the coral skeleton. This is the first study to provide a detailed description of how symbiotic hydroids attach to their host's skeleton, utilising it for physical support. Results suggest that the loss of perisarc, a characteristic commonly associated with symbiosis, allows the hydroid to utilise desmocytes for attachment. The use of these anchoring structures provides a dynamic method of attachment, facilitating detachment from the coral skeleton during extension, thereby avoiding overgrowth and smothering enabling the hydroid to remain within the host colony for prolonged periods of time. PMID:21695083

  8. High taurine levels in the Solemya velum symbiosis.

    PubMed

    Conway, N M; McDowell Capuzzo, J E

    1992-05-01

    1. To compare biochemical differences between bivalves with and without endosymbiotic chemoautotrophic bacteria, specimens of Solemya velum, a bivalve species known to contain bacterial endosymbionts, and the symbiont-free soft-shelled clam Mya arenaria, were collected from the same subtidal reducing sediments during October and November 1988. 2. Total and free amino acid compositions were determined for both species. Protein-bound amino acids were calculated as the difference between total and free amino acids. In addition, stable isotope ratios of the total and free amino acids of each species were measured to determine potential sources for these molecules. 3. Both species had similar total hydrolyzable- and protein-bound amino acid compositions; approximately 50% of the protein-bound amino acids were essential amino acids. In S. velum, the small size of the digestive system suggests that these amino acids are probably synthesized by the endosymbiotic bacteria and translocated to the animal tissue. The delta 13C and delta 15N ratios of the amino acids are very similar to the isotope ratios previously found in both the endosymbionts and whole tissues of S. velum. The relative and absolute amounts of free amino acids are very different in the two species. In S. velum, the absolute concentrations of taurine, a sulfur-containing amino acid, were greater than the total free amino acid concentrations found in other bivalves. 4. The delta 34S ratios of the free amino acids of S. velum, which were predominantly composed of taurine, were extremely negative (-17.2/1000) suggesting that taurine is synthesized using sulfur originally derived from external reduced sulfur sources, such as pore water sulfides. The possible roles for taurine in this animal-bacteria symbiosis are discussed.

  9. Functional analysis of the novel mycorrhiza-specific phosphate transporter AsPT1 and PHT1 family from Astragalus sinicus during the arbuscular mycorrhizal symbiosis.

    PubMed

    Xie, Xianan; Huang, Wu; Liu, Fengchuan; Tang, Nianwu; Liu, Yi; Lin, Hui; Zhao, Bin

    2013-05-01

    Arbuscular mycorrhizas contribute significantly to inorganic phosphate (Pi) uptake in plants. Gene networks involved in the regulation and function of the Pht1 family transporters in legume species during AM symbiosis are not fully understood. In order to characterize the six distinct members of Pht1 transporters in mycorrhizal Astragalus sinicus, we combined cellular localization, heterologous functional expression in yeast with expression/subcellular localization studies and reverse genetics approaches in planta. Pht1;1 and Pht1;4 silenced lines were generated to uncover the role of the newly discovered dependence of the AM symbiosis on another phosphate transporter AsPT1 besides AsPT4. These Pht1 transporters are triggered in Pi-starved mycorrhizal roots. AsPT1 and AsPT4 were localized in arbuscule-containing cells of the cortex. The analysis of promoter sequences revealed conserved motifs in both AsPT1 and AsPT4. AsPT1 overexpression showed higher mycorrhization levels than controls for parameters analysed, including abundance of arbuscules. By contrast, knockdown of AsPT1 by RNA interference led to degenerating or dead arbuscule phenotypes identical to that of AsPT4 silencing lines. AsPT4 but not AsPT1 is required for symbiotic Pi uptake. These results suggest that both, AsPT1 and AsPT4, are required for the AM symbiosis, most importantly, AsPT1 may serve as a novel symbiotic transporter for AM development. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  10. Structural basis for regulation of rhizobial nodulation and symbiosis gene expression by the regulatory NolR

    USDA-ARS?s Scientific Manuscript database

    The symbiosis between rhizobial microbes and host plants involves the coordinated expression of multiple genes, which leads to nodule formation and nitrogen fixation. As part of the transcriptional machinery for nodulation and symbiosis across a range of Rhizobium, NolR serves as a global regulatory...

  11. Evaluating industrial symbiosis and algae cultivation from a life cycle perspective.

    PubMed

    Soratana, Kullapa; Landis, Amy E

    2011-07-01

    A comparative life cycle assessment (LCA) was conducted on 20 scenarios of microalgae cultivation. These scenarios examined the utilization of nutrients and CO(2) from synthetic sources and waste streams as well as the materials used to construct a photobioreactor (PBR). A 0.2-m(3) closed PBR of Chlorella vulgaris at 30%-oil content by weight with the productivity of 25 g/m(2) × day was used as a case study. Results of the study show that the utilization of resources from waste streams mainly avoided global warming potential (GWP) and eutrophication impacts. Impacts from the production of material used to construct the PBR dominate total impacts in acidification and ozone depletion categories, even over longer PBR lifetimes; thus, the choice of PBR construction materials is important.

  12. Are common symbiosis genes required for endophytic rice-rhizobial interactions?

    PubMed

    Chen, Caiyan; Zhu, Hongyan

    2013-09-01

    Legume plants are able to establish root nodule symbioses with nitrogen-fixing bacteria, called rhizobia. Recent studies revealed that the root nodule symbiosis has co-opted the signaling pathway that mediates the ancestral mycorrhizal symbiosis that occurs in most land plants. Despite being unable to induce nodulation, rhizobia have been shown to be able to infect and colonize the roots of non-legumes such as rice. One fascinating question is whether establishment of such associations requires the common symbiosis (Sym) genes that are essential for infection of plant cells by mycorrhizal fungi and rhizobia in legumes. Here, we demonstrated that the common Sym genes are not required for endophytic colonization of rice roots by nitrogen-fixing rhizobia.

  13. Neo-Symbiosis: The Next Stage in the Evolution of Human Information Interaction.

    SciTech Connect

    Griffith, Douglas; Greitzer, Frank L.

    2008-12-01

    In his 1960 paper Man-Machine Symbiosis, Licklider predicted that human brains and computing machines will be coupled in a tight partnership that will think as no human brain has ever thought and process data in a way not approached by the information-handling machines we know today. Today we are on the threshold of resurrecting the vision of symbiosis. While Licklider’s original vision suggested a co-equal relationship, here we discuss an updated vision, neo-symbiosis, in which the human holds a superordinate position in an intelligent human-computer collaborative environment. This paper was originally published as a journal article and is being published as a chapter in an upcoming book series, Advances in Novel Approaches in Cognitive Informatics and Natural Intelligence.

  14. The role of PHB metabolism in the symbiosis of rhizobia with legumes.

    PubMed

    Trainer, Maria A; Charles, Trevor C

    2006-07-01

    The carbon storage polymer poly-beta-hydroxybutyrate (PHB) is a potential biodegradable alternative to plastics, which plays a key role in the cellular metabolism of many bacterial species. Most species of rhizobia synthesize PHB but not all species accumulate it during symbiosis with legumes; the reason for this remains unclear, although it was recently shown that a metabolic mutant of a nonaccumulating species retains the capacity to store PHB in symbiosis. Although the precise roles of PHB metabolism in these bacteria during infection, nodulation, and nitrogen fixation are not determined, the elucidation of these roles will influence our understanding of the metabolic nature of the symbiotic relationship. This review explores the progress that was made in determining the biochemistry and genetics of PHB metabolism. This includes the elucidation of the PHB cycle, variations in PHB metabolism among rhizobial species, and the implications of these variations, while proposing a model for the role of PHB metabolism and storage in symbiosis.

  15. Chemical identification and functional analysis of apocarotenoids involved in the development of arbuscular mycorrhizal symbiosis.

    PubMed

    Akiyama, Kohki

    2007-06-01

    Arbuscular mycorrhizae formed between more than 80% of land plants and arbuscular mycorrhizal (AM) fungi represent the most widespread symbiosis on the earth. AM fungi facilitate the uptake of soil nutrients, especially phosphate, by plants, and in return obtain carbohydrates from hosts. Apocarotenoids, oxidative cleavage products of carotenoids, have been found to play a critical role in the establishment of AM symbiosis. Strigolactones previously isolated as seed-germination stimulants for root parasitic weeds act as a chemical signal for AM fungi during presymbiotic stages. Stimulation of carotenoid metabolism, leading to massive accumulation of mycorradicin and cyclohexenone derivatives, occurs during root colonization by AM fungi. This review highlights research into the chemical identification of arbuscular mycorrhiza-related apocarotenoids and their role in the regulation and establishment of AM symbiosis conducted in the past 10 years.

  16. Impact of simulated microgravity on the normal developmental time line of an animal-bacteria symbiosis.

    PubMed

    Foster, Jamie S; Khodadad, Christina L M; Ahrendt, Steven R; Parrish, Mirina L

    2013-01-01

    The microgravity environment during space flight imposes numerous adverse effects on animal and microbial physiology. It is unclear, however, how microgravity impacts those cellular interactions between mutualistic microbes and their hosts. Here, we used the symbiosis between the host squid Euprymna scolopes and its luminescent bacterium Vibrio fischeri as a model system. We examined the impact of simulated microgravity on the timeline of bacteria-induced development in the host light organ, the site of the symbiosis. To simulate the microgravity environment, host squid and symbiosis-competent bacteria were incubated together in high-aspect ratio rotating wall vessel bioreactors and examined throughout the early stages of the bacteria-induced morphogenesis. The host innate immune response was suppressed under simulated microgravity; however, there was an acceleration of bacteria-induced apoptosis and regression in the host tissues. These results suggest that the space flight environment may alter the cellular interactions between animal hosts and their natural healthy microbiome.

  17. Dynamics of arbuscular mycorrhizal symbiosis in heavy metal phytoremediation: meta-analytical and conceptual perspectives.

    PubMed

    Audet, Patrick; Charest, Christiane

    2007-06-01

    To estimate dynamics of arbuscular mycorrhizal (AM) symbiosis in heavy metal (HM) phytoremediation, we conducted a literature survey and correlated HM uptake and relative plant growth parameters from published data. After estimating AM feedback responses for these parameters at low and high soil-HM concentration intervals, we determined that the roles of AM symbiosis are characterized by (1) an increased HM phytoextraction via mycorrhizospheric 'Enhanced Uptake' at low soil-HM concentrations, and (2) a reduced HM bioavailability via AM fungal 'Metal-Binding' processes at high soil-HM levels, hence resulting in increased plant biomass and enhanced plant tolerance through HM stress-avoidance. We present two conceptual models which illustrate the important compromise between plant growth, plant HM uptake and HM tolerance, and further emphasize the importance of AM symbiosis in buffering the soil environment for plants under such stress conditions.

  18. Influence of tobacco industry advertisements and promotions on tobacco use in India: findings from the Global Adult Tobacco Survey 2009-2010.

    PubMed

    Sinha, D N; Palipudi, K M; Oswal, K; Gupta, P C; Andes, L J; Asma, S

    2014-12-01

    The developing world, including countries like India, has become a major target for the tobacco industry to market its products. This study examines the influence of the marketing (advertising and promotion) of tobacco products on the use of tobacco by adults (ages 15 and over) in India. Data from Global Adult Tobacco Survey 2009-2010 was analyzed using methods for complex (clustered) sample designs. Multivariate logistic regression was employed to predict the use of different tobacco products by level of exposure to tobacco marketing using adults who have never used tobacco as the reference category. Odds ratios (ORs) were adjusted for education, gender, age, state of residence, wealth index, and place of residence (urban/rural). Adults in India were almost twice as likely to be current smokers (versus never users) when they were exposed to a moderate level of bidi or cigarette marketing. For bidis, among adults with high exposure, the OR for current use was 4.57 (95% confidence interval [CI]: 1.6, 13.0). Adults were more likely to be current users of smokeless tobacco (SLT) with even a low level of exposure to SLT marketing (OR = 1.24 [95% CI: 1.1, 1.4]). For SLT, the ORs showed an increasing trend (P for trend < 0.001) with greater level of exposure (moderate, OR = 1.55 [95% CI: 1.1, 2.2]; high, OR = 2.05 [95% CI: 0.8, 5.1]). The risk of any current tobacco use rose with increasing level of exposure to any marketing (minimum, OR = 1.25 [1.1-1.4]; moderate, OR = 1.38 [1.1-1.8]; and high, OR = 2.73 [1.8-4.2]), with the trend highly significant (P < 0.001). Exposure to the marketing of tobacco products, which may take the form of advertising at the point of sale, sales or a discounted price, free coupons, free samples, surrogate advertisements, or any of several other modalities, increased prevalence of tobacco use among adults. An increasing level of exposure to direct and indirect advertisement and promotion is associated with an increased likelihood of tobacco

  19. CERBERUS and NSP1 of Lotus japonicus are common symbiosis genes that modulate arbuscular mycorrhiza development.

    PubMed

    Takeda, Naoya; Tsuzuki, Syusaku; Suzaki, Takuya; Parniske, Martin; Kawaguchi, Masayoshi

    2013-10-01

    Arbuscular mycorrhizal symbiosis (AMS) and root nodule symbiosis (RNS) are mutualistic plant-microbe interactions that confer nutritional benefits to both partners. Leguminous plants possess a common genetic system for intracellular symbiosis with AM fungi and with rhizobia. Here we show that CERBERUS and NSP1, which respectively encode an E3 ubiquitin ligase and a GRAS transcriptional regulator and which have previously only been implicated in RNS, are involved in AM fungal infection in Lotus japonicus. Hyphal elongation along the longitudinal axis of the root was reduced in the cerberus mutant, giving rise to a lower colonization level. Knockout of NSP1 decreased the frequency of plants colonized by AM fungi or rhizobia. CERBERUS and NSP1 showed different patterns of expression in response to infection with symbiotic microbes. A low constitutive level of CERBERUS expression was observed in the root and an increased level of NSP1 expression was detected in arbuscule-containing cells. Induction of AM marker gene was triggered in both cerberus and nsp1 mutants by infection with symbiotic microbes; however, the mutants showed a weaker induction of marker gene expression than the wild type, mirroring their lower level of colonization. The common symbiosis genes are believed to act in an early signaling pathway for recognition of symbionts and for triggering early symbiotic responses. Our quantitative analysis of symbiotic phenotypes revealed developmental defects of the novel common symbiosis mutants in both symbioses, which demonstrates that common symbiosis mechanisms also contribute to a range of functions at later or different stages of symbiont infection.

  20. Heritable symbiosis: The advantages and perils of an evolutionary rabbit hole.

    PubMed

    Bennett, Gordon M; Moran, Nancy A

    2015-08-18

    Many eukaryotes have obligate associations with microorganisms that are transmitted directly between generations. A model for heritable symbiosis is the association of aphids, a clade of sap-feeding insects, and Buchnera aphidicola, a gammaproteobacterium that colonized an aphid ancestor 150 million years ago and persists in almost all 5,000 aphid species. Symbiont acquisition enables evolutionary and ecological expansion; aphids are one of many insect groups that would not exist without heritable symbiosis. Receiving less attention are potential negative ramifications of symbiotic alliances. In the short run, symbionts impose metabolic costs. Over evolutionary time, hosts evolve dependence beyond the original benefits of the symbiosis. Symbiotic partners enter into an evolutionary spiral that leads to irreversible codependence and associated risks. Host adaptations to symbiosis (e.g., immune-system modification) may impose vulnerabilities. Symbiont genomes also continuously accumulate deleterious mutations, limiting their beneficial contributions and environmental tolerance. Finally, the fitness interests of obligate heritable symbionts are distinct from those of their hosts, leading to selfish tendencies. Thus, genes underlying the host-symbiont interface are predicted to follow a coevolutionary arms race, as observed for genes governing host-pathogen interactions. On the macroevolutionary scale, the rapid evolution of interacting symbiont and host genes is predicted to accelerate host speciation rates by generating genetic incompatibilities. However, degeneration of symbiont genomes may ultimately limit the ecological range of host species, potentially increasing extinction risk. Recent results for the aphid-Buchnera symbiosis and related systems illustrate that, whereas heritable symbiosis can expand ecological range and spur diversification, it also presents potential perils.

  1. Heritable symbiosis: The advantages and perils of an evolutionary rabbit hole

    PubMed Central

    Bennett, Gordon M.; Moran, Nancy A.

    2015-01-01

    Many eukaryotes have obligate associations with microorganisms that are transmitted directly between generations. A model for heritable symbiosis is the association of aphids, a clade of sap-feeding insects, and Buchnera aphidicola, a gammaproteobacterium that colonized an aphid ancestor 150 million years ago and persists in almost all 5,000 aphid species. Symbiont acquisition enables evolutionary and ecological expansion; aphids are one of many insect groups that would not exist without heritable symbiosis. Receiving less attention are potential negative ramifications of symbiotic alliances. In the short run, symbionts impose metabolic costs. Over evolutionary time, hosts evolve dependence beyond the original benefits of the symbiosis. Symbiotic partners enter into an evolutionary spiral that leads to irreversible codependence and associated risks. Host adaptations to symbiosis (e.g., immune-system modification) may impose vulnerabilities. Symbiont genomes also continuously accumulate deleterious mutations, limiting their beneficial contributions and environmental tolerance. Finally, the fitness interests of obligate heritable symbionts are distinct from those of their hosts, leading to selfish tendencies. Thus, genes underlying the host–symbiont interface are predicted to follow a coevolutionary arms race, as observed for genes governing host–pathogen interactions. On the macroevolutionary scale, the rapid evolution of interacting symbiont and host genes is predicted to accelerate host speciation rates by generating genetic incompatibilities. However, degeneration of symbiont genomes may ultimately limit the ecological range of host species, potentially increasing extinction risk. Recent results for the aphid–Buchnera symbiosis and related systems illustrate that, whereas heritable symbiosis can expand ecological range and spur diversification, it also presents potential perils. PMID:25713367

  2. How drought and salinity affect arbuscular mycorrhizal symbiosis and strigolactone biosynthesis?

    PubMed

    López-Ráez, Juan A

    2016-06-01

    This paper reviews the importance of AM symbiosis in alleviating plant stress under unfavourable environmental conditions, making emphasis on the role of strigolactones. A better understanding of the mechanisms that regulate this beneficial association will increase its potential use as an innovative and sustainable strategy in modern agriculture. Plants are very dynamic systems with a great capacity for adaptation to a constantly changing environment. This phenotypic plasticity is particularly advantageous in areas damaged or subjected to intensive agriculture. Nowadays, global crop production systems are intensifying the impact on natural resources, such as water availability. Therefore, there is an urgent need to find more sustainable alternatives. One of the plant strategies to improve phenotypic plasticity is to establish mutualistic beneficial associations with soil microorganisms, such as the arbuscular mycorrhizal (AM) fungi. The establishment of AM symbiosis requires a complex network of interconnected signalling pathways, in which phytohormones play a key role. Strigolactones (SLs) are plant hormones acting as modulators of the coordinated development under nutrient shortage. SLs also act as host detection signals for AM fungi, favouring symbiosis establishment. In this review, current knowledge on the effect of water-related stresses, such as drought and salinity, in AM symbiosis and in SL production is discussed. Likewise, how the symbiosis helps the host plant to alleviate stress symptoms is also reviewed. Finally, we highlight how interactions between hormonal signalling pathways modulate all these responses, especially in the cross-talk between SLs and abscisic acid (ABA). Understanding the intricate mechanisms that regulate the establishment of AM symbiosis and the plant responses under unfavourable conditions will contribute to implement the use of AM fungi as bioprotective agents against these stresses.

  3. Périgord black truffle genome uncovers evolutionary origins and mechanisms of symbiosis.

    PubMed

    Martin, Francis; Kohler, Annegret; Murat, Claude; Balestrini, Raffaella; Coutinho, Pedro M; Jaillon, Olivier; Montanini, Barbara; Morin, Emmanuelle; Noel, Benjamin; Percudani, Riccardo; Porcel, Bettina; Rubini, Andrea; Amicucci, Antonella; Amselem, Joelle; Anthouard, Véronique; Arcioni, Sergio; Artiguenave, François; Aury, Jean-Marc; Ballario, Paola; Bolchi, Angelo; Brenna, Andrea; Brun, Annick; Buée, Marc; Cantarel, Brandi; Chevalier, Gérard; Couloux, Arnaud; Da Silva, Corinne; Denoeud, France; Duplessis, Sébastien; Ghignone, Stefano; Hilselberger, Benoît; Iotti, Mirco; Marçais, Benoît; Mello, Antonietta; Miranda, Michele; Pacioni, Giovanni; Quesneville, Hadi; Riccioni, Claudia; Ruotolo, Roberta; Splivallo, Richard; Stocchi, Vilberto; Tisserant, Emilie; Viscomi, Arturo Roberto; Zambonelli, Alessandra; Zampieri, Elisa; Henrissat, Bernard; Lebrun, Marc-Henri; Paolocci, Francesco; Bonfante, Paola; Ottonello, Simone; Wincker, Patrick

    2010-04-15

    The Périgord black truffle (Tuber melanosporum Vittad.) and the Piedmont white truffle dominate today's truffle market. The hypogeous fruiting body of T. melanosporum is a gastronomic delicacy produced by an ectomycorrhizal symbiont endemic to calcareous soils in southern Europe. The worldwide demand for this truffle has fuelled intense efforts at cultivation. Identification of processes that condition and trigger fruit body and symbiosis formation, ultimately leading to efficient crop production, will be facilitated by a thorough analysis of truffle genomic traits. In the ectomycorrhizal Laccaria bicolor, the expansion of gene families may have acted as a 'symbiosis toolbox'. This feature may however reflect evolution of this particular taxon and not a general trait shared by all ectomycorrhizal species. To get a better understanding of the biology and evolution of the ectomycorrhizal symbiosis, we report here the sequence of the haploid genome of T. melanosporum, which at approximately 125 megabases is the largest and most complex fungal genome sequenced so far. This expansion results from a proliferation of transposable elements accounting for approximately 58% of the genome. In contrast, this genome only contains approximately 7,500 protein-coding genes with very rare multigene families. It lacks large sets of carbohydrate cleaving enzymes, but a few of them involved in degradation of plant cell walls are induced in symbiotic tissues. The latter feature and the upregulation of genes encoding for lipases and multicopper oxidases suggest that T. melanosporum degrades its host cell walls during colonization. Symbiosis induces an increased expression of carbohydrate and amino acid transporters in both L. bicolor and T. melanosporum, but the comparison of genomic traits in the two ectomycorrhizal fungi showed that genetic predispositions for symbiosis-'the symbiosis toolbox'-evolved along different ways in ascomycetes and basidiomycetes.

  4. Photovoltaics industry profile

    SciTech Connect

    1980-10-01

    A description of the status of the US photovoltaics industry is given. Principal end-user industries are identified, domestic and foreign market trends are discussed, and industry-organized and US government-organized trade promotion events are listed. Trade associations and trade journals are listed, and a photovoltaic product manufacturers list is included. (WHK)

  5. A widespread plant-fungal-bacterial symbiosis promotes plant biodiversity, plant nutrition and seedling recruitment

    PubMed Central

    van der Heijden, Marcel GA; Bruin, Susanne de; Luckerhoff, Ludo; van Logtestijn, Richard SP; Schlaeppi, Klaus

    2016-01-01

    Highly diverse microbial assemblages colonize plant roots. It is still poorly understood whether different members of this root microbiome act synergistically by supplying different services (for example, different limiting nutrients) to plants and plant communities. In order to test this, we manipulated the presence of two widespread plant root symbionts, arbuscular mycorrhizal fungi and nitrogen-fixing rhizobia bacteria in model grassland communities established in axenic microcosms. Here, we demonstrate that both symbionts complement each other resulting in increased plant diversity, enhanced seedling recruitment and improved nutrient acquisition compared with a single symbiont situation. Legume seedlings obtained up to 15-fold higher productivity if they formed an association with both symbionts, opposed to productivity they reached with only one symbiont. Our results reveal the importance of functional diversity of symbionts and demonstrate that different members of the root microbiome can complement each other in acquiring different limiting nutrients and in driving important ecosystem functions. PMID:26172208

  6. A widespread plant-fungal-bacterial symbiosis promotes plant biodiversity, plant nutrition and seedling recruitment.

    PubMed

    van der Heijden, Marcel G A; de Bruin, Susanne; Luckerhoff, Ludo; van Logtestijn, Richard S P; Schlaeppi, Klaus

    2016-02-01

    Highly diverse microbial assemblages colonize plant roots. It is still poorly understood whether different members of this root microbiome act synergistically by supplying different services (for example, different limiting nutrients) to plants and plant communities. In order to test this, we manipulated the presence of two widespread plant root symbionts, arbuscular mycorrhizal fungi and nitrogen-fixing rhizobia bacteria in model grassland communities established in axenic microcosms. Here, we demonstrate that both symbionts complement each other resulting in increased plant diversity, enhanced seedling recruitment and improved nutrient acquisition compared with a single symbiont situation. Legume seedlings obtained up to 15-fold higher productivity if they formed an association with both symbionts, opposed to productivity they reached with only one symbiont. Our results reveal the importance of functional diversity of symbionts and demonstrate that different members of the root microbiome can complement each other in acquiring different limiting nutrients and in driving important ecosystem functions.

  7. Radiation Fields in Blazars - a Possible Extension of the Small Scale Symbiosis (Disk/Jet) into a Large Scale (Dust/Dust) Symbiosis

    NASA Astrophysics Data System (ADS)

    Donea, Alina-C.; Protheroe, Raymond J.

    In blazar models both protons and electrons may be efficiently accelerated in jets and produce γ-rays. Here we discuss the interactions of these γ-rays with different radiation fields. The external radiation fields within a few parsecs from the black hole involved in such interactions could be the direct radiation from the accretion disk coupled with the jet, the infrared radiation from a dusty torus, and the emission line radiation from the broad line region surrounding the accretion disk. The optical thickness for absorption of γ-ray photons in the external radiation fields is analysed for blazars and quasars. Based on the unification theory of active galactic nuclei we briefly review the evidence for the existence of small scale dust tori in blazars/FR I. We propose that the existing jet-accretion disk symbiosis extrapolates to a large scale symbiosis between other important dusty constituents of the blazar/FR I family.

  8. Location and Survival of Mycorrhiza Helper Pseudomonas fluorescens during Establishment of Ectomycorrhizal Symbiosis between Laccaria bicolor and Douglas Fir

    PubMed Central

    Frey-Klett, P.; Pierrat, J. C.; Garbaye, J.

    1997-01-01

    The mycorrhiza helper bacterium Pseudomonas fluorescens BBc6, isolated from a Laccaria bicolor sporocarp, consistently promotes L. bicolor-Douglas fir (Pseudotsuga menziesii) ectomycorrhizal formation, even with low doses of bacterial inoculum. In order to describe this phenomenon more accurately, we have looked at the location and survival of the introduced bacterial strain in the soil and in the rhizosphere during the establishment of mycorrhizal symbiosis in glasshouse and nursery experiments. Bacterial populations were quantified with a spontaneous, stable, rifampin-resistant mutant, BBc6R8, which phenotypically conformed to the parental strain. BBc6R8 populations declined rapidly, reaching the detection limit after 19 weeks, and did not increase either when L. bicolor sporocarps were forming in autumn or when Douglas fir roots resumed growing in spring. BBc6R8 was neither an endophyte nor a rhizobacterium. Furthermore, it was not particularly associated with either mycorrhizas of Douglas fir-L. bicolor or L. bicolor sporocarps. Surprisingly, a significant mycorrhiza helper effect was observed when the inoculated BBc6R8 population had dropped as low as 30 CFU g of dry matter(sup-1) in the soil. This study raises questions concerning the bacterial concentration in the soil which is effective for promotion of mycorrhizal establishment and the timing of the bacterial effect. It allows us to develop working hypotheses, which can be tested experimentally, to identify the mechanisms of the mycorrhiza helper effect. PMID:16535478

  9. Industrial estate planning and management in India--an integrated approach towards industrial ecology.

    PubMed

    Singhal, Shaleen; Kapur, Amit

    2002-09-01

    Industrial estates (IE) are today perceived as an integral part of development strategies of many countries worldwide. The environmental impacts from a concentration of large number of industries in a small area or unplanned IE, can pose a serious threat to both local and global sustainable development initiatives. The formation of ecologically balanced industrial systems can result in numerous environmental and economic benefits. This paper examines the relevance of industrial symbiosis and carrying capacity concepts and proposes an integrated approach towards IE planning in India based on grouping combinations of industries based on carrying capacity, formation of green industrial townships, development of environmental impact assessment guidelines for IE and implementation of environmental management systems.

  10. Litter-forager termite mounds enhance the ectomycorrhizal symbiosis between Acacia holosericea A. Cunn. Ex G. Don and Scleroderma dictyosporum isolates.

    PubMed

    Duponnois, Robin; Assikbetse, Komi; Ramanankierana, Heriniaina; Kisa, Marija; Thioulouse, Jean; Lepage, Michel

    2006-05-01

    The hypothesis of the present study was that the termite mounds of Macrotermes subhyalinus (MS) (a litter-forager termite) were inhabited by a specific microflora that could enhance with the ectomycorrhizal fungal development. We tested the effect of this feeding group mound material on (i) the ectomycorrhization symbiosis between Acacia holosericea (an Australian Acacia introduced in the sahelian areas) and two ectomycorrhizal fungal isolates of Scleroderma dictyosporum (IR408 and IR412) in greenhouse conditions, (ii) the functional diversity of soil microflora and (iii) the diversity of fluorescent pseudomonads. The results showed that the termite mound amendment significantly increased the ectomycorrhizal expansion. MS mound amendment and ectomycorrhizal inoculation induced strong modifications of the soil functional microbial diversity by promoting the multiplication of carboxylic acid catabolizing microorganisms. The phylogenetic analysis showed that fluorescent pseudomonads mostly belong to the Pseudomonads monteillii species. One of these, P. monteillii isolate KR9, increased the ectomycorrhizal development between S. dictyosporum IR412 and A. holosericea. The occurrence of MS termite mounds could be involved in the expansion of ectomycorrhizal symbiosis and could be implicated in nutrient flow and local diversity.

  11. Arbuscular mycorrhizal symbiosis and methyl jasmonate avoid the inhibition of root hydraulic conductivity caused by drought.

    PubMed

    Sánchez-Romera, Beatriz; Ruiz-Lozano, Juan Manuel; Zamarreño, Ángel María; García-Mina, José María; Aroca, Ricardo

    2016-02-01

    Hormonal regulation and symbiotic relationships provide benefits for plants to overcome stress conditions. The aim of this study was to elucidate the effects of exogenous methyl jasmonate (MeJA) application on root hydraulic conductivity (L) of Phaseolus vulgaris plants which established arbuscular mycorrhizal (AM) symbiosis under two water regimes (well-watered and drought conditions). The variation in endogenous contents of several hormones (MeJA, JA, abscisic acid (ABA), indol-3-acetic acid (IAA), salicylic acid (SA)) and the changes in aquaporin gene expression, protein abundance and phosphorylation state were analyzed. AM symbiosis decreased L under well-watered conditions, which was partially reverted by the MeJA treatment, apparently by a drop in root IAA contents. Also, AM symbiosis and MeJA prevented inhibition of L under drought conditions, most probably by a reduction in root SA contents. Additionally, the gene expression of two fungal aquaporins was upregulated under drought conditions, independently of the MeJA treatment. Plant aquaporin gene expression could not explain the behaviour of L. Conversely, evidence was found for the control of L by phosphorylation of aquaporins. Hence, MeJA addition modified the response of L to both AM symbiosis and drought, presumably by regulating the root contents of IAA and SA and the phosphorylation state of aquaporins.

  12. [Effect of five fungicides on growth of Glycyrrhiza uralensis and efficiency of mycorrhizal symbiosis].

    PubMed

    Li, Peng-ying; Yang, Guang; Zhou, Xiu-teng; Zhou, Liane-yun; Shao, Ai-juan; Chen, Mei-lan

    2015-12-01

    In order to obtain the fungicides with minimal impact on efficiency of mycorrhizal symbiosis, the effect of five fungicides including polyoxins, jinggangmycins, thiophanate methylate, chlorothalonil and carbendazim on the growth of medicinal plant and efficiency of mycorrhizal symbiosis were studied. Pot cultured Glycyrrhiza uralensis was treated with different fungicides with the concentration that commonly used in the field. 60 d after treated with fungicides, infection rate, infection density, biomass indexes, photosyn- thetic index and the content of active component were measured. Experimental results showed that carbendazim had the strongest inhibition on mycorrhizal symbiosis effect. Carbendazim significantly inhibited the mycorrhizal infection rate, significantly suppressed the actual photosynthetic efficiency of G. uralensis and the most indicators of biomass. Polyoxins showed the lowest inhibiting affection. Polyoxins had no significant effect on mycorrhizal infection rate, the actual photosynthetic efficiency of G. uralensis and the most indicators of biomass. The other three fungicides also had an inhibitory effect on efficiency of mycorrhizal symbiosis, and the inhibition degrees were all between polyoxins's and carbendazim's. The author considered that fungicide's inhibition degree on mycorrhizal effect might be related with the species of fungicides, so the author suggested that the farmer should try to choose bio-fungicides like polyoxins.

  13. Effects of nano-TiO2 on the agronomically-relevant Rhizobium-legume symbiosis

    USDA-ARS?s Scientific Manuscript database

    The impact of nano-TiO2 on Rhizobium-legume symbiosis was studied using garden peas and the compatible bacterial partner Rhizobium leguminosarum bv. viciae 3841. Exposure to nano-TiO2 did not affect the germination of peas grown aseptically, nor did it impact the gross root structure. However, nano-...

  14. Insights on the Impact of Arbuscular Mycorrhizal Symbiosis on Tomato Tolerance to Water Stress1[OPEN

    PubMed Central

    Siciliano, Ilenia

    2016-01-01

    Arbuscular mycorrhizal (AM) fungi, which form symbioses with the roots of the most important crop species, are usually considered biofertilizers, whose exploitation could represent a promising avenue for the development in the future of a more sustainable next-generation agriculture. The best understood function in symbiosis is an improvement in plant mineral nutrient acquisition, as exchange for carbon compounds derived from the photosynthetic process: this can enhance host growth and tolerance to environmental stresses, such as water stress (WS). However, physiological and molecular mechanisms occurring in arbuscular mycorrhiza-colonized plants and directly involved in the mitigation of WS effects need to be further investigated. The main goal of this work is to verify the potential impact of AM symbiosis on the plant response to WS. To this aim, the effect of two AM fungi (Funneliformis mosseae and Rhizophagus intraradices) on tomato (Solanum lycopersicum) under the WS condition was studied. A combined approach, involving ecophysiological, morphometric, biochemical, and molecular analyses, has been used to highlight the mechanisms involved in plant response to WS during AM symbiosis. Gene expression analyses focused on a set of target genes putatively involved in the plant response to drought, and in parallel, we considered the expression changes induced by the imposed stress on a group of fungal genes playing a key role in the water-transport process. Taken together, the results show that AM symbiosis positively affects the tolerance to WS in tomato, with a different plant response depending on the AM fungi species involved. PMID:27208301

  15. Temperature shapes coral-algal symbiosis in the South China Sea

    PubMed Central

    Tong, Haoya; Cai, Lin; Zhou, Guowei; Yuan, Tao; Zhang, Weipeng; Tian, Renmao; Huang, Hui; Qian, Pei-Yuan

    2017-01-01

    With the increase in sea surface temperature (SST), scleractinian corals are exposed to bleaching threats but may possess certain flexibilities in terms of their associations with symbiotic algae. Previous studies have shown a close symbiosis between coral the and Symbiodinium; however, the spatial variation of the symbiosis and the attribution underlying are not well understood. In the present study, we examined coral-algal symbiosis in Galaxea fascicularis and Montipora spp. from three biogeographic regions across ~10° of latitude in the South China Sea. Analysis of similarities (ANOSIM) indicated a highly flexible coral-algal symbiosis in both G. fascicularis and Montipora spp. and canonical correspondence analysis (CCA) showed that temperature explained 83.2% and 60.1% of the explanatory subclade variations in G. fascicularis and Montipora spp., respectively, which suggested that temperature was the main environmental factor contributing to the diversity of Symbiodinium across the three regions. The geographic specificity of the Symbiodinium phylogeny was identified, revealing possible environmental selection across the three regions. These results suggest that scleractinian corals may have the ability to regulate Symbiodinium community structures under different temperatures and thus be able to adapt to gradual climate change. PMID:28084322

  16. The promiscuous larvae: flexibility in the establishment of symbiosis in corals

    NASA Astrophysics Data System (ADS)

    Cumbo, V. R.; Baird, A. H.; van Oppen, M. J. H.

    2013-03-01

    Coral reefs thrive in part because of the symbiotic partnership between corals and Symbiodinium. While this partnership is one of the keys to the success of coral reef ecosystems, surprisingly little is known about many aspects of coral symbiosis, in particular the establishment and development of symbiosis in host species that acquire symbionts anew in each generation. More specifically, the point at which symbiosis is established (i.e., larva vs. juvenile) remains uncertain, as does the source of free-living Symbiodinium in the environment. In addition, the capacity of host and symbiont to form novel combinations is unknown. To explore patterns of initial association between host and symbiont, larvae of two species of Acropora were exposed to sediment collected from three locations on the Great Barrier Reef. A high proportion of larvae established symbiosis shortly after contact with sediments, and Acropora larvae were promiscuous, taking up multiple types of Symbiodinium. The Symbiodinium types acquired from the sediments reflected the symbiont assemblage within a wide range of cnidarian hosts at each of the three sites, suggesting potential regional differences in the free-living Symbiodinium assemblage. Coral larvae clearly have the capacity to take up Symbiodinium prior to settlement, and sediment is a likely source. Promiscuous larvae allow species to associate with Symbiodinium appropriate for potentially novel environments that may be experienced following dispersal.

  17. Effects of nano-ZnO on the agronomically relevant Rhizobium-legume symbiosis

    USDA-ARS?s Scientific Manuscript database

    The impact of nano-ZnO (nZnO) on Rhizobium-legume symbiosis was studied with garden pea and its compatible bacterial partner Rhizobium leguminosarum bv. viciae 3841. Exposure of peas to nZnO had no impact on germination, but significantly affected root length. Chronic exposure of plant to nZnO impac...

  18. The effect of pseudo-microgravity on the symbiosis of plants and microorganisms

    NASA Astrophysics Data System (ADS)

    Tomita-Yokotani, Kaori; Maki, Asano; Aoki, Toshio; Tamura, Kenji; Wada, Hidenori; Hashimoto, Hirofumi; Yamashita, Masamichi

    The symbiosis of plants and microorganisms is important to conduct agriculture under space environment. However, we have less knowledge on whether this kind of symbiosis can be established under space condition. We examined the functional compounds responsible to symbiosis between rhizobiaum and Lotus japonicus as a model of symbiotic combination. The existence of the substances for their symbiosis, some flavonoids, have already been known from the study of gene expression, but the detail structures have not yet been elucidated. Pseudomicrogravity was generated by the 3D-clinorotation. Twenty flavonoids were found in the extracts of 16 days plants of Lotus japonicus grown under the normal gravity by HPLC. Content of two flavonoids among them was affected by the infection of Mesorhizobium loti to them. It has a possibility that the two flavonoids were key substances for their combination process. The productions of those flavonoids were confirmed also under the pseudo-microgravity. The amount of one flavonoid was increased by both infection of rhizobium and exposure to the normal and pseudo-micro gravity. Chemical species of these flavonoids were identified by LC- ESI/MS and spectroscopic analysis. To show the effects of pseudo-microgravity on the gene expression, enzymic activities related to the functional compounds are evaluated after the rhizobial infection.

  19. Temperature shapes coral-algal symbiosis in the South China Sea.

    PubMed

    Tong, Haoya; Cai, Lin; Zhou, Guowei; Yuan, Tao; Zhang, Weipeng; Tian, Renmao; Huang, Hui; Qian, Pei-Yuan

    2017-01-13

    With the increase in sea surface temperature (SST), scleractinian corals are exposed to bleaching threats but may possess certain flexibilities in terms of their associations with symbiotic algae. Previous studies have shown a close symbiosis between coral the and Symbiodinium; however, the spatial variation of the symbiosis and the attribution underlying are not well understood. In the present study, we examined coral-algal symbiosis in Galaxea fascicularis and Montipora spp. from three biogeographic regions across ~10° of latitude in the South China Sea. Analysis of similarities (ANOSIM) indicated a highly flexible coral-algal symbiosis in both G. fascicularis and Montipora spp. and canonical correspondence analysis (CCA) showed that temperature explained 83.2% and 60.1% of the explanatory subclade variations in G. fascicularis and Montipora spp., respectively, which suggested that temperature was the main environmental factor contributing to the diversity of Symbiodinium across the three regions. The geographic specificity of the Symbiodinium phylogeny was identified, revealing possible environmental selection across the three regions. These results suggest that scleractinian corals may have the ability to regulate Symbiodinium community structures under different temperatures and thus be able to adapt to gradual climate change.

  20. Bacterial Leaf Symbiosis in Angiosperms: Host Specificity without Co-Speciation

    PubMed Central

    Lemaire, Benny; Vandamme, Peter; Merckx, Vincent; Smets, Erik; Dessein, Steven

    2011-01-01

    Bacterial leaf symbiosis is a unique and intimate interaction between bacteria and flowering plants, in which endosymbionts are organized in specialized leaf structures. Previously, bacterial leaf symbiosis has been described as a cyclic and obligate interaction in which the endosymbionts are vertically transmitted between plant generations and lack autonomous growth. Theoretically this allows for co-speciation between leaf nodulated plants and their endosymbionts. We sequenced the nodulated Burkholderia endosymbionts of 54 plant species from known leaf nodulated angiosperm genera, i.e. Ardisia, Pavetta, Psychotria and Sericanthe. Phylogenetic reconstruction of bacterial leaf symbionts and closely related free-living bacteria indicates the occurrence of multiple horizontal transfers of bacteria from the environment to leaf nodulated plant species. This rejects the hypothesis of a long co-speciation process between the bacterial endosymbionts and their host plants. Our results indicate a recent evolutionary process towards a stable and host specific interaction confirming the proposed maternal transmission mode of the endosymbionts through the seeds. Divergence estimates provide evidence for a relatively recent origin of bacterial leaf symbiosis, dating back to the Miocene (5–23 Mya). This geological epoch was characterized by cool and arid conditions, which may have triggered the origin of bacterial leaf symbiosis. PMID:21915326

  1. A hexA homologue from Photorhabdus regulates pathogenicity, symbiosis and phenotypic variation.

    PubMed

    Joyce, Susan A; Clarke, David J

    2003-03-01

    Photorhabdus is a genus of entomopathogenic Gram-negative bacteria that belong to the family Enterobactericeae. Remarkably, at the same time as being pathogenic to insect larvae, Photorhabdus also have a mutualistic relationship with entomophagous nematodes of the family Heterorhabditiae. Photorhabdus can be isolated in two phenotypically distinct forms, termed the primary and secondary variant. Both variants grow equally well and are equally virulent when injected into insect larvae. However, only the primary variant can colonize the intestinal tract of the IJ stage of the nematode and support nematode growth and development. The primary variant expresses several phenotypes that are absent from the secondary variant, including the production of extracellular enzymes, pigments, antibiotics and light. In this study, we use Photorhabdus temperata strain K122 to show that these primary-specific products are symbiosis factors, i.e. factors that are required for nematode growth and development. We also show that, in P. temperata K122, the production of these symbiosis factors is repressed in the secondary variant by the protein encoded by a gene with homology to hexA from Erwinia. Moreover, the derepression of the symbiosis factors in the secondary variant results in a significant attenuation of virulence to larvae of the greater wax moth, Galleria mellonella. This suggests that, during a normal infection, pathogenicity and symbiosis must be temporally separated and that HexA is involved in the regulation of this pathogen-symbiont transition.

  2. Plant nodulation inducers enhance horizontal gene transfer of Azorhizobium caulinodans symbiosis island.

    PubMed

    Ling, Jun; Wang, Hui; Wu, Ping; Li, Tao; Tang, Yu; Naseer, Nawar; Zheng, Huiming; Masson-Boivin, Catherine; Zhong, Zengtao; Zhu, Jun

    2016-11-29

    Horizontal gene transfer (HGT) of genomic islands is a driving force of bacterial evolution. Many pathogens and symbionts use this mechanism to spread mobile genetic elements that carry genes important for interaction with their eukaryotic hosts. However, the role of the host in this process remains unclear. Here, we show that plant compounds inducing the nodulation process in the rhizobium-legume mutualistic symbiosis also enhance the transfer of symbiosis islands. We demonstrate that the symbiosis island of the Sesbania rostrata symbiont, Azorhizobium caulinodans, is an 87.6-kb integrative and conjugative element (ICE(Ac)) that is able to excise, form a circular DNA, and conjugatively transfer to a specific site of gly-tRNA gene of other rhizobial genera, expanding their host range. The HGT frequency was significantly increased in the rhizosphere. An ICE(Ac)-located LysR-family transcriptional regulatory protein AhaR triggered the HGT process in response to plant flavonoids that induce the expression of nodulation genes through another LysR-type protein, NodD. Our study suggests that rhizobia may sense rhizosphere environments and transfer their symbiosis gene contents to other genera of rhizobia, thereby broadening rhizobial host-range specificity.

  3. R gene-controlled host specificity in the legume-rhizobia symbiosis

    USDA-ARS?s Scientific Manuscript database

    Leguminous plants can enter into root nodule symbioses with nitrogen-fixing soil bacteria known as rhizobia. An intriguing but still poorly understood property of the symbiosis is its host specificity, which is controlled at multiple levels involving both rhizobial and host genes. Here we report the...

  4. Positive Gene Regulation by a Natural Protective miRNA Enables Arbuscular Mycorrhizal Symbiosis.

    PubMed

    Couzigou, Jean-Malo; Lauressergues, Dominique; André, Olivier; Gutjahr, Caroline; Guillotin, Bruno; Bécard, Guillaume; Combier, Jean-Philippe

    2017-01-11

    Arbuscular mycorrhizal (AM) symbiosis associates most plants with fungi of the phylum Glomeromycota. The fungus penetrates into roots and forms within cortical cell branched structures called arbuscules for nutrient exchange. We discovered that miR171b has a mismatched cleavage site and is unable to downregulate the miR171 family target gene, LOM1 (LOST MERISTEMS 1). This mismatched cleavage site is conserved among plants that establish AM symbiosis, but not in non-mycotrophic plants. Unlike other members of the miR171 family, miR171b stimulates AM symbiosis and is expressed specifically in root cells that contain arbuscules. MiR171b protects LOM1 from negative regulation by other miR171 family members. These findings uncover a unique mechanism of positive post-transcriptional regulation of gene expression by miRNAs and demonstrate its relevance for the establishment of AM symbiosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Role of Hfq in an animal-microbe symbiosis under simulated microgravity conditions

    NASA Astrophysics Data System (ADS)

    Grant, Kyle C.; Khodadad, Christina L. M.; Foster, Jamie S.

    2014-01-01

    Microgravity has a profound impact on the physiology of pathogenic microbes; however, its effects on mutualistic microbes are relatively unknown. To examine the effects of microgravity on those beneficial microbes that associate with animal tissues, we used the symbiosis between the bobtail squid Euprymna scolopes and a motile, luminescent bacterium, Vibrio fischeri as a model system. Specifically, we examined the role of Hfq, an RNA-binding protein known to be an important global regulator under space flight conditions, in the squid-vibrio symbiosis under simulated microgravity. To mimic a reduced gravity environment, the symbiotic partners were co-incubated in high-aspect-ratio rotating wall vessel bioreactors and examined at various stages of development. Results indicated that under simulated microgravity, hfq expression was down-regulated in V. fischeri. A mutant strain defective in hfq showed no colonization phenotype, indicating that Hfq was not required to initiate the symbiosis with the host squid. However, the hfq mutant showed attenuated levels of apoptotic cell death, a key symbiosis phenotype, within the host light organ suggesting that Hfq does contribute to normal light organ morphogenesis. Results also indicated that simulated microgravity conditions accelerated the onset of cell death in wild-type cells but not in the hfq mutant strains. These data suggest that Hfq plays an important role in the mutualism between V. fischeri and its animal host and that its expression can be negatively impacted by simulated microgravity conditions.

  6. Bacterial leaf symbiosis in angiosperms: host specificity without co-speciation.

    PubMed

    Lemaire, Benny; Vandamme, Peter; Merckx, Vincent; Smets, Erik; Dessein, Steven

    2011-01-01

    Bacterial leaf symbiosis is a unique and intimate interaction between bacteria and flowering plants, in which endosymbionts are organized in specialized leaf structures. Previously, bacterial leaf symbiosis has been described as a cyclic and obligate interaction in which the endosymbionts are vertically transmitted between plant generations and lack autonomous growth. Theoretically this allows for co-speciation between leaf nodulated plants and their endosymbionts. We sequenced the nodulated Burkholderia endosymbionts of 54 plant species from known leaf nodulated angiosperm genera, i.e. Ardisia, Pavetta, Psychotria and Sericanthe. Phylogenetic reconstruction of bacterial leaf symbionts and closely related free-living bacteria indicates the occurrence of multiple horizontal transfers of bacteria from the environment to leaf nodulated plant species. This rejects the hypothesis of a long co-speciation process between the bacterial endosymbionts and their host plants. Our results indicate a recent evolutionary process towards a stable and host specific interaction confirming the proposed maternal transmission mode of the endosymbionts through the seeds. Divergence estimates provide evidence for a relatively recent origin of bacterial leaf symbiosis, dating back to the Miocene (5-23 Mya). This geological epoch was characterized by cool and arid conditions, which may have triggered the origin of bacterial leaf symbiosis.

  7. Community analysis of microbial sharing and specialization in a Costa Rican ant-plant-hemipteran symbiosis.

    PubMed

    Pringle, Elizabeth G; Moreau, Corrie S

    2017-03-15

    Ants have long been renowned for their intimate mutualisms with trophobionts and plants and more recently appreciated for their widespread and diverse interactions with microbes. An open question in symbiosis research is the extent to which environmental influence, including the exchange of microbes between interacting macroorganisms, affects the composition and function of symbiotic microbial communities. Here we approached this question by investigating symbiosis within symbiosis. Ant-plant-hemipteran symbioses are hallmarks of tropical ecosystems that produce persistent close contact among the macroorganism partners, which then have substantial opportunity to exchange symbiotic microbes. We used metabarcoding and quantitative PCR to examine community structure of both bacteria and fungi in a Neotropical ant-plant-scale-insect symbiosis. Both phloem-feeding scale insects and honeydew-feeding ants make use of microbial symbionts to subsist on phloem-derived diets of suboptimal nutritional quality. Among the insects examined here, Cephalotes ants and pseudococcid scale insects had the most specialized bacterial symbionts, whereas Azteca ants appeared to consume or associate with more fungi than bacteria, and coccid scale insects were associated with unusually diverse bacterial communities. Despite these differences, we also identified apparent sharing of microbes among the macro-partners. How microbial exchanges affect the consumer-resource interactions that shape the evolution of ant-plant-hemipteran symbioses is an exciting question that awaits further research. © 2017 The Author(s).

  8. Temperature shapes coral-algal symbiosis in the South China Sea

    NASA Astrophysics Data System (ADS)

    Tong, Haoya; Cai, Lin; Zhou, Guowei; Yuan, Tao; Zhang, Weipeng; Tian, Renmao; Huang, Hui; Qian, Pei-Yuan

    2017-01-01

    With the increase in sea surface temperature (SST), scleractinian corals are exposed to bleaching threats but may possess certain flexibilities in terms of their associations with symbiotic algae. Previous studies have shown a close symbiosis between coral the and Symbiodinium; however, the spatial variation of the symbiosis and the attribution underlying are not well understood. In the present study, we examined coral-algal symbiosis in Galaxea fascicularis and Montipora spp. from three biogeographic regions across ~10° of latitude in the South China Sea. Analysis of similarities (ANOSIM) indicated a highly flexible coral-algal symbiosis in both G. fascicularis and Montipora spp. and canonical correspondence analysis (CCA) showed that temperature explained 83.2% and 60.1% of the explanatory subclade variations in G. fascicularis and Montipora spp., respectively, which suggested that temperature was the main environmental factor contributing to the diversity of Symbiodinium across the three regions. The geographic specificity of the Symbiodinium phylogeny was identified, revealing possible environmental selection across the three regions. These results suggest that scleractinian corals may have the ability to regulate Symbiodinium community structures under different temperatures and thus be able to adapt to gradual climate change.

  9. Comparative study of selected Brazilian and Nigerian policies to promote the transfer and development of technology: the role of regime and non-regime factors, and some results from the automobile industry, 1967-80

    SciTech Connect

    Gusau, B.H.

    1985-01-01

    This study is concerned with the policies adopted by Brazil and Nigeria to promote the transfer and development of technology in industry. The objectives are two-fold: (1) to compare and analyze the policies with respect to the automobile industries in the 1967-1980 period; (2) to investigate whether their adoption was solely a function of the different ideological values and issue levels of economic development of the countries, or whether the regimes are solely an expression of the patterns of that development. The study adopted the Comparative Public Policy approach to explore the various hypotheses formulated. The findings showed that Brazil realized more significant results than Nigeria in technology development, while in other areas, such as the curtailment of imports, employment generation, etc., the results are mixed. The study concludes that both regime and industrial development factors influence the variation in the policies, although the regime factor seems to explain more of the variation.

  10. Replicon-dependent differentiation of symbiosis-related genes in Sinorhizobium strains nodulating Glycine max.

    PubMed

    Guo, Hui Juan; Wang, En Tao; Zhang, Xing Xing; Li, Qin Qin; Zhang, Yan Ming; Tian, Chang Fu; Chen, Wen Xin

    2014-02-01

    In order to investigate the genetic differentiation of Sinorhizobium strains nodulating Glycine max and related microevolutionary mechanisms, three housekeeping genes (SMc00019, truA, and thrA) and 16 symbiosis-related genes on the chromosome (7 genes), pSymA (6 genes), and pSymB (3 genes) were analyzed. Five distinct species were identified among the test strains by calculating the average nucleotide identity (ANI) of SMc00019-truA-thrA: Sinorhizobium fredii, Sinorhizobium sojae, Sinorhizobium sp. I, Sinorhizobium sp. II, and Sinorhizobium sp. III. These species assignments were also supported by population genetics and phylogenetic analyses of housekeeping genes and symbiosis-related genes on the chromosome and pSymB. Different levels of genetic differentiation were observed among these species or different replicons. S. sojae was the most divergent from the other test species and was characterized by its low intraspecies diversity and limited geographic distribution. Intergenic recombination dominated the evolution of 19 genes from different replicons. Intraspecies recombination happened frequently in housekeeping genes and symbiosis-related genes on the chromosome and pSymB, whereas pSymA genes showed a clear pattern of lateral-transfer events between different species. Moreover, pSymA genes were characterized by a lower level of polymorphism and recombination than those on the chromosome and pSymB. Taken together, genes from different replicons of rhizobia might be involved in the establishment of symbiosis with legumes, but these symbiosis-related genes might have evolved differently according to their corresponding replicons.

  11. Replicon-Dependent Differentiation of Symbiosis-Related Genes in Sinorhizobium Strains Nodulating Glycine max

    PubMed Central

    Guo, Hui Juan; Wang, En Tao; Zhang, Xing Xing; Li, Qin Qin; Zhang, Yan Ming; Chen, Wen Xin

    2014-01-01

    In order to investigate the genetic differentiation of Sinorhizobium strains nodulating Glycine max and related microevolutionary mechanisms, three housekeeping genes (SMc00019, truA, and thrA) and 16 symbiosis-related genes on the chromosome (7 genes), pSymA (6 genes), and pSymB (3 genes) were analyzed. Five distinct species were identified among the test strains by calculating the average nucleotide identity (ANI) of SMc00019-truA-thrA: Sinorhizobium fredii, Sinorhizobium sojae, Sinorhizobium sp. I, Sinorhizobium sp. II, and Sinorhizobium sp. III. These species assignments were also supported by population genetics and phylogenetic analyses of housekeeping genes and symbiosis-related genes on the chromosome and pSymB. Different levels of genetic differentiation were observed among these species or different replicons. S. sojae was the most divergent from the other test species and was characterized by its low intraspecies diversity and limited geographic distribution. Intergenic recombination dominated the evolution of 19 genes from different replicons. Intraspecies recombination happened frequently in housekeeping genes and symbiosis-related genes on the chromosome and pSymB, whereas pSymA genes showed a clear pattern of lateral-transfer events between different species. Moreover, pSymA genes were characterized by a lower level of polymorphism and recombination than those on the chromosome and pSymB. Taken together, genes from different replicons of rhizobia might be involved in the establishment of symbiosis with legumes, but these symbiosis-related genes might have evolved differently according to their corresponding replicons. PMID:24317084

  12. Metal toxicity differently affects the Iris pseudacorus-arbuscular mycorrhiza fungi symbiosis in terrestrial and semi-aquatic habitats.

    PubMed

    Wężowicz, K; Turnau, K; Anielska, T; Zhebrak, I; Gołuszka, K; Błaszkowski, J; Rozpądek, P

    2015-12-01

    Phytoremediation offers an environmental friendly alternative to conventional cleanup techniques. In this study, mycorrhizal fungi isolated from the roots of Mentha longifolia grown in the basin of the Centuria River (S Poland) were used. Iris pseudacorus was grown in substratum from an industrial waste, enriched in Pb, Fe, Zn, and Cd in a terrestrial and water-logged habitat. Plant yield and photosynthetic performance was the highest in the aquatic environment; however, the presence of toxic metals (TM) negatively affected photosystem II (PSII) photochemistry as shown by the JIP test. Fungi colonization and Cd accumulation within plant tissues was decreased. In the terrestrial habitat, neither arbuscular mycorrhizal fungi (AMF) nor metal toxicity affected plant growth, although metal uptake, Cd in particular, as well as photosynthesis were affected. Inoculated plants accumulated significantly more Cd, and photosynthesis was downregulated. The results presented in this study clearly indicate that the I. pseudacorus-AMF symbiosis adapts itself to the presence of toxic metals in the environment, optimizing resource supply, energy fluxes, and possibly stress tolerance mechanisms. Plant/AMF consortia grown in terrestrial and water-logged habitats utilize different strategies to cope with metal toxicity. The use of AMF in improving the phytoremediation potential of I. pseudacorus needs, however, further research.

  13. A Functional Approach towards Understanding the Role of the Mitochondrial Respiratory Chain in an Endomycorrhizal Symbiosis

    PubMed Central

    Mercy, Louis; Lucic-Mercy, Eva; Nogales, Amaia; Poghosyan, Areg; Schneider, Carolin; Arnholdt-Schmitt, Birgit

    2017-01-01

    Arbuscular mycorrhizal fungi (AMF) are crucial components of fertile soils, able to provide several ecosystem services for crop production. Current economic, social and legislative contexts should drive the so-called “second green revolution” by better exploiting these beneficial microorganisms. Many challenges still need to be overcome to better understand the mycorrhizal symbiosis, among which (i) the biotrophic nature of AMF, constraining their production, while (ii) phosphate acts as a limiting factor for the optimal mycorrhizal inoculum application and effectiveness. Organism fitness and adaptation to the changing environment can be driven by the modulation of mitochondrial respiratory chain, strongly connected to the phosphorus processing. Nevertheless, the role of the respiratory function in mycorrhiza remains largely unexplored. We hypothesized that the two mitochondrial respiratory chain components, alternative oxidase (AOX) and cytochrome oxidase (COX), are involved in specific mycorrhizal behavior. For this, a complex approach was developed. At the pre-symbiotic phase (axenic conditions), we studied phenotypic responses of Rhizoglomus irregulare spores with two AOX and COX inhibitors [respectively, salicylhydroxamic acid (SHAM) and potassium cyanide (KCN)] and two growth regulators (abscisic acid – ABA and gibberellic acid – Ga3). At the symbiotic phase, we analyzed phenotypic and transcriptomic (genes involved in respiration, transport, and fermentation) responses in Solanum tuberosum/Rhizoglomus irregulare biosystem (glasshouse conditions): we monitored the effects driven by ABA, and explored the modulations induced by SHAM and KCN under five phosphorus concentrations. KCN and SHAM inhibited in vitro spore germination while ABA and Ga3 induced differential spore germination and hyphal patterns. ABA promoted mycorrhizal colonization, strong arbuscule intensity and positive mycorrhizal growth dependency (MGD). In ABA treated plants, R. irregulare

  14. Screening for differentially expressed genes in Anoectochilus roxburghii (Orchidaceae) during symbiosis with the mycorrhizal fungus Epulorhiza sp.

    PubMed

    Li, Biao; Tang, Mingjuan; Tang, Kun; Zhao, Lifang; Guo, Shunxing

    2012-02-01

    Mycorrhizal fungi promote the growth and development of plants, including medicinal plants. The mechanisms by which this growth promotion occurs are of theoretical interest and practical importance to agriculture. Here, an endophytic fungus (AR-18) was isolated from roots of the orchid Anoectochilus roxburghii growing in the wild, and identified as Epulorhiza sp. Tissue-cultured seedlings of A. roxburghii were inoculated with AR-18 and co-cultured for 60 d. Endotrophic mycorrhiza formed and the growth of A. roxburghii was markedly promoted by the fungus. To identify genes in A. roxburghii that were differentially expressed during the symbiosis with AR-18, we used the differential display reverse transcription polymerase chain reaction (DDRT-PCR) method to compare the transcriptomes between seedlings inoculated with the fungus and control seedlings. We amplified 52 DDRT-PCR bands using 15 primer combinations of three anchor primers and five arbitrary primers, and nine bands were re-amplified by double primers. Reverse Northern blot analyses were used to further screen the bands. Five clones were up-regulated in the symbiotic interaction, including genes encoding a uracil phosphoribosyltransferase (UPRTs; EC 2.4.2.9) and a hypothetical protein. One gene encoding an amino acid transmembrane transporter was down-regulated, and one gene encoding a tRNA-Lys (trnK) and a maturase K (matK) pseudogene were expressed only in the inoculated seedlings. The possible roles of the above genes, especially the UPRTs and matK genes, are discussed in relation to the fungal interaction. This study is the first of its type in A. roxburghii.

  15. 7 CFR 1220.112 - Industry information.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.112 Industry information. The... markets, new marketing strategies, or increased efficiency for the soybean industry, and activities...

  16. 7 CFR 1220.112 - Industry information.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.112 Industry information. The... markets, new marketing strategies, or increased efficiency for the soybean industry, and activities...

  17. 7 CFR 1220.112 - Industry information.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AGREEMENTS AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE SOYBEAN PROMOTION, RESEARCH, AND CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.112 Industry information. The... markets, new marketing strategies, or increased efficiency for the soybean industry, and activities...

  18. A Legume TOR Protein Kinase Regulates Rhizobium Symbiosis and Is Essential for Infection and Nodule Development1[OPEN

    PubMed Central

    Blanco, Lourdes; Quinto, Carmen

    2016-01-01

    The target of rapamycin (TOR) protein kinase regulates metabolism, growth, and life span in yeast, animals, and plants in coordination with nutrient status and environmental conditions. The nutrient-dependent nature of TOR functionality makes this kinase a putative regulator of symbiotic associations involving nutrient acquisition. However, TOR’s role in these processes remains to be understood. Here, we uncovered the role of TOR during the bean (Phaseolus vulgaris)-Rhizobium tropici (Rhizobium) symbiotic interaction. TOR was expressed in all tested bean tissues, with higher transcript levels in the root meristems and senesced nodules. We showed TOR promoter expression along the progressing infection thread and in the infected cells of mature nodules. Posttranscriptional gene silencing of TOR using RNA interference (RNAi) showed that this gene is involved in lateral root elongation and root cell organization and also alters the density, size, and number of root hairs. The suppression of TOR transcripts also affected infection thread progression and associated cortical cell divisions, resulting in a drastic reduction of nodule numbers. TOR-RNAi resulted in reduced reactive oxygen species accumulation and altered CyclinD1 and CyclinD3 expression, which are crucial factors for infection thread progression and nodule organogenesis. Enhanced expression of TOR-regulated ATG genes in TOR-RNAi roots suggested that TOR plays a role in the recognition of Rhizobium as a symbiont. Together, these data suggest that TOR plays a vital role in the establishment of root nodule symbiosis in the common bean. PMID:27698253

  19. Proteomic analysis as a tool for investigating arsenic stress in Pteris vittata roots colonized or not by arbuscular mycorrhizal symbiosis.

    PubMed

    Bona, Elisa; Marsano, Francesco; Massa, Nadia; Cattaneo, Chiara; Cesaro, Patrizia; Argese, Emanuele; Sanità di Toppi, Luigi; Cavaletto, Maria; Berta, Graziella

    2011-08-12

    Pteris vittata can tolerate very high soil arsenic concentration and rapidly accumulates the metalloid in its fronds. However, its tolerance to arsenic has not been completely explored. Arbuscular mycorrhizal (AM) fungi colonize the root of most terrestrial plants, including ferns. Mycorrhizae are known to affect plant responses in many ways: improving plant nutrition, promoting plant tolerance or resistance to pathogens, drought, salinity and heavy metal stresses. It has been observed that plants growing on arsenic polluted soils are usually mycorrhizal and that AM fungi enhance arsenic tolerance in a number of plant species. The aim of the present work was to study the effects of the AM fungus Glomus mosseae on P. vittata plants treated with arsenic using a proteomic approach. Image analysis showed that 37 spots were differently affected (21 identified). Arsenic treatment affected the expression of 14 spots (12 up-regulated and 2 down-regulated), while in presence of G. mosseae modulated 3 spots (1 up-regulated and 2 down-regulated). G. mosseae, in absence of arsenic, modulated 17 spots (13 up-regulated and 4 down-regulated). Arsenic stress was observed even in an arsenic tolerant plant as P. vittata and a protective effect of AM symbiosis toward arsenic stress was observed.

  20. Potential Symbiosis-Specific Genes Uncovered by Sequencing a 410-Kilobase DNA Region of the Bradyrhizobium japonicum Chromosome

    PubMed Central

    Göttfert, Michael; Röthlisberger, Sandra; Kündig, Christoph; Beck, Christoph; Marty, Roger; Hennecke, Hauke

    2001-01-01

    The physical and genetic map of the Bradyrhizobium japonicum chromosome revealed that nitrogen fixation and nodulation genes are clustered. Because of the complex interactions between the bacterium and the plant, we expected this chromosomal sector to contain additional genes that are involved in the maintenance of an efficient symbiosis. Therefore, we determined the nucleotide sequence of a 410-kb region. The overall G+C nucleotide content was 59.1%. Using a minimum gene length of 150 nucleotides, 388 open reading frames (ORFs) were selected as coding regions. Thirty-five percent of the predicted proteins showed similarity to proteins of rhizobia. Sixteen percent were similar only to proteins of other bacteria. No database match was found for 29%. Repetitive DNA sequence-derived ORFs accounted for the rest. The sequenced region contained all nitrogen fixation genes and, apart from nodM, all nodulation genes that were known to exist in B. japonicum. We found several genes that seem to encode transport systems for ferric citrate, molybdate, or carbon sources. Some of them are preceded by −24/−12 promoter elements. A number of putative outer membrane proteins and cell wall-modifying enzymes as well as a type III secretion system might be involved in the interaction with the host. PMID:11157954

  1. A model symbiosis reveals a role for sheathed-flagellum rotation in the release of immunogenic lipopolysaccharide.

    PubMed

    Brennan, Caitlin A; Hunt, Jason R; Kremer, Natacha; Krasity, Benjamin C; Apicella, Michael A; McFall-Ngai, Margaret J; Ruby, Edward G

    2014-03-04

    Bacterial flagella mediate host-microbe interactions through tissue tropism during colonization, as well as by activating immune responses. The flagellar shaft of some bacteria, including several human pathogens, is encased in a membranous sheath of unknown function. While it has been hypothesized that the sheath may allow these bacteria to evade host responses to the immunogenic flagellin subunit, this unusual structural feature has remained an enigma. Here we demonstrate that the rotation of the sheathed flagellum in both the mutualist Vibrio fischeri and the pathogen Vibrio cholerae promotes release of a potent bacteria-derived immunogen, lipopolysaccharide, found in the flagellar sheath. We further present a new role for the flagellar sheath in triggering, rather than circumventing, host immune responses in the model squid-vibrio symbiosis. Such an observation not only has implications for the study of bacterial pathogens with sheathed flagella, but also raises important biophysical questions of sheathed-flagellum function. DOI: http://dx.doi.org/10.7554/eLife.01579.001.

  2. Host-selected mutations converging on a global regulator drive an adaptive leap towards symbiosis in bacteria

    PubMed Central

    Sabrina Pankey, M; Foxall, Randi L; Ster, Ian M; Perry, Lauren A; Schuster, Brian M; Donner, Rachel A; Coyle, Matthew; Cooper, Vaughn S; Whistler, Cheryl A

    2017-01-01

    Host immune and physical barriers protect against pathogens but also impede the establishment of essential symbiotic partnerships. To reveal mechanisms by which beneficial organisms adapt to circumvent host defenses, we experimentally evolved ecologically distinct bioluminescent Vibrio fischeri by colonization and growth within the light organs of the squid Euprymna scolopes. Serial squid passaging of bacteria produced eight distinct mutations in the binK sensor kinase gene, which conferred an exceptional selective advantage that could be demonstrated through both empirical and theoretical analysis. Squid-adaptive binK alleles promoted colonization and immune evasion that were mediated by cell-associated matrices including symbiotic polysaccharide (Syp) and cellulose. binK variation also altered quorum sensing, raising the threshold for luminescence induction. Preexisting coordinated regulation of symbiosis traits by BinK presented an efficient solution where altered BinK function was the key to unlock multiple colonization barriers. These results identify a genetic basis for microbial adaptability and underscore the importance of hosts as selective agents that shape emergent symbiont populations. DOI: http://dx.doi.org/10.7554/eLife.24414.001 PMID:28447935

  3. Symbiosis between hydra and chlorella: molecular phylogenetic analysis and experimental study provide insight into its origin and evolution.

    PubMed

    Kawaida, Hitomi; Ohba, Kohki; Koutake, Yuhki; Shimizu, Hiroshi; Tachida, Hidenori; Kobayakawa, Yoshitaka

    2013-03-01

    Although many physiological studies have been reported on the symbiosis between hydra and green algae, very little information from a molecular phylogenetic aspect of symbiosis is available. In order to understand the origin and evolution of symbiosis between the two organisms, we compared the phylogenetic relationships among symbiotic green algae with the phylogenetic relationships among host hydra strains. To do so, we reconstructed molecular phylogenetic trees of several strains of symbiotic chlorella harbored in the endodermal epithelial cells of viridissima group hydra strains and investigated their congruence with the molecular phylogenetic trees of the host hydra strains. To examine the species specificity between the host and the symbiont with respect to the genetic distance, we also tried to introduce chlorella strains into two aposymbiotic strains of viridissima group hydra in which symbiotic chlorella had been eliminated in advance. We discussed the origin and history of symbiosis between hydra and green algae based on the analysis. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Arbuscular mycorrhizal symbiosis mitigates the negative effects of salinity on durum wheat.

    PubMed

    Fileccia, Veronica; Ruisi, Paolo; Ingraffia, Rosolino; Giambalvo, Dario; Frenda, Alfonso Salvatore; Martinelli, Federico

    2017-01-01

    Arbuscular mycorrhizal (AM) symbiosis is generally considered to be effective in ameliorating the plant tolerance to salt stress. Unfortunately, the comprehension of the mechanisms implicated in salinity stress alleviation by AM symbiosis is far from being complete. Thus, an experiment was performed by growing durum wheat (Triticum durum Desf.) plants under salt-stress conditions to evaluate the influence of AM symbiosis on both the plant growth and the regulation of a number of genes related to salt stress and nutrient uptake. Durum wheat plants were grown outdoors in pots in absence or in presence of salt stress and with or without AM fungi inoculation. The inoculum consisted of a mixture of spores of Rhizophagus irregularis (formerly Glomus intraradices) and Funneliformis mosseae (formerly G. mosseae). Results indicate that AM symbiosis can alleviate the detrimental effects of salt stress on the growth of durum wheat plants. In fact, under salt stress conditions mycorrhizal plants produced more aboveground and root biomass, had higher N uptake and aboveground N concentration, and showed greater stability of plasma membranes compared to non-mycorrhizal plants. Inoculation with AM fungi had no effect on the expression of the N transporter genes AMT1.1, AMT1.2, and NAR2.2, either under no-stress or salt stress conditions, probably due to the fact that plants were grown under optimal N conditions; on the contrary, NRT1.1 was always upregulated by AM symbiosis. Moreover, the level of expression of the drought stress-related genes AQP1, AQP4, PIP1, DREB5, and DHN15.3 observed in the mycorrhizal stressed plants was markedly lower than that observed in the non-mycorrhizal stressed plants and very close to that observed in the non-stressed plants. Our hypothesis is that, in the present study, AM symbiosis did not increase the plant tolerance to salt stress but instead generated a condition in which plants were subjected to a level of salt stress lower than that of non

  5. The bifunctional plant receptor, OsCERK1, regulates both chitin-triggered immunity and arbuscular mycorrhizal symbiosis in rice.

    PubMed

    Miyata, Kana; Kozaki, Toshinori; Kouzai, Yusuke; Ozawa, Kenjirou; Ishii, Kazuo; Asamizu, Erika; Okabe, Yoshihiro; Umehara, Yosuke; Miyamoto, Ayano; Kobae, Yoshihiro; Akiyama, Kohki; Kaku, Hanae; Nishizawa, Yoko; Shibuya, Naoto; Nakagawa, Tomomi

    2014-11-01

    Plants are constantly exposed to threats from pathogenic microbes and thus developed an innate immune system to protect themselves. On the other hand, many plants also have the ability to establish endosymbiosis with beneficial microbes such as arbuscular mycorrhizal (AM) fungi or rhizobial bacteria, which improves the growth of host plants. How plants evolved these systems managing such opposite plant-microbe interactions is unclear. We show here that knockout (KO) mutants of OsCERK1, a rice receptor kinase essential for chitin signaling, were impaired not only for chitin-triggered defense responses but also for AM symbiosis, indicating the bifunctionality of OsCERK1 in defense and symbiosis. On the other hand, a KO mutant of OsCEBiP, which forms a receptor complex with OsCERK1 and is essential for chitin-triggered immunity, established mycorrhizal symbiosis normally. Therefore, OsCERK1 but not chitin-triggered immunity is required for AM symbiosis. Furthermore, experiments with chimeric receptors showed that the kinase domains of OsCERK1 and homologs from non-leguminous, mycorrhizal plants could trigger nodulation signaling in legume-rhizobium interactions as the kinase domain of Nod factor receptor1 (NFR1), which is essential for triggering the nodulation program in leguminous plants, did. Because leguminous plants are believed to have developed the rhizobial symbiosis on the basis of AM symbiosis, our results suggest that the symbiotic function of ancestral CERK1 in AM symbiosis enabled the molecular evolution to leguminous NFR1 and resulted in the establishment of legume-rhizobia symbiosis. These results also suggest that OsCERK1 and homologs serve as a molecular switch that activates defense or symbiotic responses depending on the infecting microbes.

  6. Symbiosis of Steel, Energy, and CO2 Evolution in Korea

    NASA Astrophysics Data System (ADS)

    Lee, Hyunjoung; Matsuura, Hiroyuki; Sohn, Il

    2016-09-01

    This study looks at the energy intensity of the steel industry and the greenhouse gas intensity involved with the production of steel. Using several sources of steel production data and the corresponding energy sources used provides a time-series analysis of the greenhouse gas (GHG) and energy intensity from 1990 to 2014. The impact of the steel economy with the gross domestic product (GDP) provides indirect importance of the general manufacturing sector within Korea and in particular the steel industry. Beyond 2008, the shift in excess materials production and significant increase in total imports have led to an imbalance in the Korean steel market and continue to inhibit the growth of the domestic steel market. The forecast of the GHG and energy intensity along with the steel production up to 2030 is provided using the auto regressive integrated moving average analysis.

  7. Framing Service, Benefit, and Credibility Through Images and Texts: A Content Analysis of Online Promotional Messages of Korean Medical Tourism Industry.

    PubMed

    Jun, Jungmi

    2016-07-01

    This study examines how the Korean medical tourism industry frames its service, benefit, and credibility issues through texts and images of online brochures. The results of content analysis suggest that the Korean medical tourism industry attempts to frame their medical/health services as "excellence in surgeries and cancer care" and "advanced health technology and facilities." However, the use of cost-saving appeals was limited, which can be seen as a strategy to avoid consumers' association of lower cost with lower quality services, and to stress safety and credibility.

  8. Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists.

    PubMed

    Kohler, Annegret; Kuo, Alan; Nagy, Laszlo G; Morin, Emmanuelle; Barry, Kerrie W; Buscot, Francois; Canbäck, Björn; Choi, Cindy; Cichocki, Nicolas; Clum, Alicia; Colpaert, Jan; Copeland, Alex; Costa, Mauricio D; Doré, Jeanne; Floudas, Dimitrios; Gay, Gilles; Girlanda, Mariangela; Henrissat, Bernard; Herrmann, Sylvie; Hess, Jaqueline; Högberg, Nils; Johansson, Tomas; Khouja, Hassine-Radhouane; LaButti, Kurt; Lahrmann, Urs; Levasseur, Anthony; Lindquist, Erika A; Lipzen, Anna; Marmeisse, Roland; Martino, Elena; Murat, Claude; Ngan, Chew Y; Nehls, Uwe; Plett, Jonathan M; Pringle, Anne; Ohm, Robin A; Perotto, Silvia; Peter, Martina; Riley, Robert; Rineau, Francois; Ruytinx, Joske; Salamov, Asaf; Shah, Firoz; Sun, Hui; Tarkka, Mika; Tritt, Andrew; Veneault-Fourrey, Claire; Zuccaro, Alga; Tunlid, Anders; Grigoriev, Igor V; Hibbett, David S; Martin, Francis

    2015-04-01

    To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergent evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.

  9. Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists

    DOE PAGES

    Kohler, Annegret; Kuo, Alan; Nagy, Laszlo G.; ...

    2015-02-23

    To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergentmore » evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.« less

  10. Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists

    SciTech Connect

    Kohler, Annegret; Kuo, Alan; Nagy, Laszlo G.; Morin, Emmanuelle; Barry, Kerrie W.; Buscot, Francois; Canbäck, Björn; Choi, Cindy; Cichocki, Nicolas; Clum, Alicia; Colpaert, Jan; Copeland, Alex; Costa, Mauricio D.; Doré, Jeanne; Floudas, Dimitrios; Gay, Gilles; Girlanda, Mariangela; Henrissat, Bernard; Herrmann, Sylvie; Hess, Jaqueline; Högberg, Nils; Johansson, Tomas; Khouja, Hassine-Radhouane; LaButti, Kurt; Lahrmann, Urs; Levasseur, Anthony; Lindquist, Erika A.; Lipzen, Anna; Marmeisse, Roland; Martino, Elena; Murat, Claude; Ngan, Chew Y.; Nehls, Uwe; Plett, Jonathan M.; Pringle, Anne; Ohm, Robin A.; Perotto, Silvia; Peter, Martina; Riley, Robert; Rineau, Francois; Ruytinx, Joske; Salamov, Asaf; Shah, Firoz; Sun, Hui; Tarkka, Mika; Tritt, Andrew; Veneault-Fourrey, Claire; Zuccaro, Alga; Tunlid, Anders; Grigoriev, Igor V.; Hibbett, David S.; Martin, Francis

    2015-02-23

    To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergent evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.

  11. Transcriptomic Analysis of Sinorhizobium meliloti and Medicago truncatula Symbiosis Using Nitrogen Fixation-Deficient Nodules.

    PubMed

    Lang, Claus; Long, Sharon R

    2015-08-01

    The bacterium Sinorhizobium meliloti interacts symbiotically with legume plant hosts such as Medicago truncatula to form nitrogen-fixing root nodules. During symbiosis, plant and bacterial cells differentiate in a coordinated manner, resulting in specialized plant cells that contain nitrogen-fixing bacteroids. Both plant and bacterial genes are required at each developmental stage of symbiosis. We analyzed gene expression in nodules formed by wild-type bacteria on six plant mutants with defects in nitrogen fixation. We observed differential expression of 482 S. meliloti genes with functions in cell envelope homeostasis, cell division, stress response, energy metabolism, and nitrogen fixation. We simultaneously analyzed gene expression in M. truncatula and observed differential regulation of host processes that may trigger bacteroid differentiation and control bacterial infection. Our analyses of developmentally arrested plant mutants indicate that plants use distinct means to control bacterial infection during early and late symbiotic stages.

  12. Symbiosis with Francisella tularensis provides resistance to pathogens in the silkworm

    PubMed Central

    Suzuki, Jin; Uda, Akihiko; Watanabe, Kenta; Shimizu, Takashi; Watarai, Masahisa

    2016-01-01

    Francisella tularensis, the causative agent of tularemia, is a highly virulent facultative intracellular pathogen found in a wide range of animals, including arthropods, and environments. This bacterium has been known for over 100 years, but the lifestyle of F. tularensis in natural reservoirs remains largely unknown. Thus, we established a novel natural host model for F. tularensis using the silkworm (Bombyx mori), which is an insect model for infection by pathogens. F. tularensis established a symbiosis with silkworms, and bacteria were observed in the hemolymph. After infection with F. tularensis, the induction of melanization and nodulation, which are immune responses to bacterial infection, were inhibited in silkworms. Pre-inoculation of silkworms with F. tularensis enhanced the expression of antimicrobial peptides and resistance to infection by pathogenic bacteria. These results suggest that silkworms acquire host resistance via their symbiosis with F. tularensis, which may have important fitness benefits in natural reservoirs. PMID:27507264

  13. Symbiosis of sea anemones and hermit crabs: different resource utilization patterns in the Aegean Sea

    NASA Astrophysics Data System (ADS)

    Vafeiadou, Anna-Maria; Antoniadou, Chryssanthi; Chintiroglou, Chariton

    2012-09-01

    The small-scale distribution and resource utilization patterns of hermit crabs living in symbiosis with sea anemones were investigated in the Aegean Sea. Four hermit crab species, occupying shells of nine gastropod species, were found in symbiosis with the sea anemone Calliactis parasitica. Shell resource utilization patterns varied among hermit crabs, with Dardanus species utilizing a wide variety of shells. The size structure of hermit crab populations also affected shell resource utilization, with small-sized individuals inhabiting a larger variety of shells. Sea anemone utilization patterns varied both among hermit crab species and among residence shells, with larger crabs and shells hosting an increased abundance and biomass of C. parasitica. The examined biometric relationships suggested that small-sized crabs carry, proportionally to their weight, heavier shells and increased anemone biomass than larger ones. Exceptions to the above patterns are related either to local resource availability or to other environmental factors.

  14. Physiological and antioxidant responses of Medicago sativa-rhizobia symbiosis to cyanobacterial toxins (Microcystins) exposure.

    PubMed

    El Khalloufi, Fatima; Oufdou, Khalid; Lahrouni, Majida; Faghire, Mustapha; Peix, Alvaro; Ramírez-Bahena, Martha Helena; Vasconcelos, Vitor; Oudra, Brahim

    2013-12-15

    Toxic cyanobacteria in freshwaters can induce potent harmful effects on growth and development of plants irrigated with contaminated water. In this study, the effect of cyanobacteria extract containing Microcystins (MC) on Medicago sativa-rhizobia symbiosis was investigated in order to explore plants response through biomass production, photosynthetic pigment and antioxidant enzymes analysis: Peroxidase (POD), Polyphenoloxidase (PPO) and Catalase (CAT). Alfalfa plants were inoculated with two endosymbiotic rhizobial strains: RhOL1 (MC less sensitive strain) and RhOL3 (MC more sensitive strain), to evaluate the rhizobial contribution on the plant response cultured under cyanobacterial toxins stress. The two rhizobia strains were identified as Ensifer meliloti by sequence analysis of their rrs and atpD genes. The chronic exposure to MC extract showed shoot, root and nodules dry weight decrease, in both symbiosis cultures. The rate of decline in plants inoculated with RhOL3 was higher than that in symbiosis with RhOL1 mainly at 20 μg L(-1) of MC. Cyanotoxins also reduced photosynthetic pigment content and generated an oxidative stress observed at cellular level. POD, PPO and CAT activities were significantly increased in leaves, roots and nodules of alfalfa plants exposed to MC. These enzyme activities were higher in plants inoculated with RhOL3 especially when alfalfa plants were exposed to 20 μg L(-1) of MC. The present paper reports new scientific finding related to the behavior of rhizobia-M. sativa associations to MC (Microcystins) for later recommendation concerning the possible use of these symbiosis face to crops exposure to MC contaminated water irrigation.

  15. The Impact of Nitrogen Limitation and Mycorrhizal Symbiosis on Aspen Tree Growth and Development

    SciTech Connect

    Tran, Bich Thi Ngoc

    2014-08-18

    Nitrogen deficiency is the most common and widespread nutritional deficiency affecting plants worldwide. Ectromycorrhizal symbiosis involves the beneficial interaction of plants with soil fungi and plays a critical role in nutrient cycling, including the uptake of nitrogen from the environment. The main goal of this study is to understand how limiting nitrogen in the presence or absence of an ectomycorrhizal fungi, Laccaria bicolor, affects the health of aspen trees, Populus temuloides.

  16. Oak root response to ectomycorrhizal symbiosis establishment: RNA-Seq derived transcript identification and expression profiling.

    PubMed

    Sebastiana, Mónica; Vieira, Bruno; Lino-Neto, Teresa; Monteiro, Filipa; Figueiredo, Andreia; Sousa, Lisete; Pais, Maria Salomé; Tavares, Rui; Paulo, Octávio S

    2014-01-01

    Ectomycorrhizal symbiosis is essential for the life and health of trees in temperate and boreal forests where it plays a major role in nutrient cycling and in functioning of the forest ecosystem. Trees with ectomycorrhizal root tips are more tolerant to environmental stresses, such as drought, and biotic stresses such as root pathogens. Detailed information on these molecular processes is essential for the understanding of symbiotic tissue development in order to optimize the benefits of this natural phenomenon. Next generation sequencing tools allow the analysis of non model ectomycorrhizal plant-fungal interactions that can contribute to find the "symbiosis toolkits" and better define the role of each partner in the mutualistic interaction. By using 454 pyrosequencing we compared ectomycorrhizal cork oak roots with non-symbiotic roots. From the two cDNA libraries sequenced, over 2 million reads were obtained that generated 19,552 cork oak root unique transcripts. A total of 2238 transcripts were found to be differentially expressed when ECM roots were compared with non-symbiotic roots. Identification of up- and down-regulated gens in ectomycorrhizal roots lead to a number of insights into the molecular mechanisms governing this important symbiosis. In cork oak roots, ectomycorrhizal colonization resulted in extensive cell wall remodelling, activation of the secretory pathway, alterations in flavonoid biosynthesis, and expression of genes involved in the recognition of fungal effectors. In addition, we identified genes with putative roles in symbiotic processes such as nutrient exchange with the fungal partner, lateral root formation or root hair decay. These findings provide a global overview of the transcriptome of an ectomycorrhizal host root, and constitute a foundation for future studies on the molecular events controlling this important symbiosis.

  17. Sinorhizobium meliloti requires a cobalamin-dependent ribonucleotide reductase for symbiosis with its plant host

    PubMed Central

    Taga, Michiko E.; Walker, Graham C.

    2010-01-01

    Vitamin B12 (cobalamin) is a critical cofactor for animals and protists, yet its biosynthesis is limited to prokaryotes. We previously showed that the symbiotic nitrogen-fixing alphaproteobacterium Sinorhizobium meliloti requires cobalamin to establish a symbiotic relationship with its plant host, Medicago sativa (alfalfa). Here, the specific requirement for cobalamin in the S. meliloti-alfalfa symbiosis was investigated. Of the three known cobalamin-dependent enzymes in S. meliloti, the methylmalonyl CoA mutase (BhbA) does not affect symbiosis whereas disruption of the metH gene encoding the cobalamin-dependent methionine synthase causes a significant defect in symbiosis. Expression of the cobalamin-independent methionine synthase MetE alleviates this symbiotic defect, indicating that the requirement for methionine synthesis does not reflect a need for the cobalamin-dependent enzyme. To investigate the function of the cobalamin-dependent ribonucleotide reductase (RNR) encoded by nrdJ, S. meliloti was engineered to express an Escherichia coli cobalamin-independent (Class Ia) RNR instead of nrdJ. This strain is severely defective in symbiosis. Electron micrographs show that these cells can penetrate alfalfa nodules but are unable to differentiate into nitrogen-fixing bacteroids and instead are lysed in the plant cytoplasm. Flow cytometry analysis indicates that these bacteria are largely unable to undergo endoreduplication. These phenotypes may be due to the inactivation of the Class Ia RNR by reactive oxygen species and/or inadequate oxygen availability in the nodule. These results show that the critical role of the cobalamin-dependent RNR for survival of S. meliloti in its plant host can account for the considerable resources that S. meliloti dedicates to cobalamin biosynthesis. PMID:20698752

  18. Expression patterns of sterol transporters NPC1 and NPC2 in the cnidarian-dinoflagellate symbiosis.

    PubMed

    Dani, Vincent; Priouzeau, Fabrice; Mertz, Marjolijn; Mondin, Magali; Pagnotta, Sophie; Lacas-Gervais, Sandra; Davy, Simon K; Sabourault, Cécile

    2017-10-01

    The symbiotic interaction between cnidarians (e.g., corals and sea anemones) and photosynthetic dinoflagellates of the genus Symbiodinium is triggered by both host-symbiont recognition processes and metabolic exchange between the 2 partners. The molecular communication is crucial for homeostatic regulation of the symbiosis, both under normal conditions and during stresses that further lead to symbiosis collapse. It is therefore important to identify and fully characterise the key players of this intimate interaction at the symbiotic interface. In this study, we determined the cellular and subcellular localization and expression of the sterol-trafficking Niemann-Pick type C proteins (NPC1 and NPC2) in the symbiotic sea anemones Anemonia viridis and Aiptasia sp. We first established that NPC1 is localised within vesicles in host tissues and to the symbiosome membranes in several anthozoan species. We demonstrated that the canonical NPC2-a protein is mainly expressed in the epidermis, whereas the NPC2-d protein is closely associated with symbiosome membranes. Furthermore, we showed that the expression of the NPC2-d protein is correlated with symbiont presence in healthy symbiotic specimens. As npc2-d is a cnidarian-specific duplicated gene, we hypothesised that it probably arose from a subfunctionalisation process that might result in a gain of function and symbiosis adaptation in anthozoans. Niemann-Pick type C proteins may be key players in a functional symbiosis and be useful tools to study host-symbiont interactions in the anthozoan-dinoflagellate association. © 2017 John Wiley & Sons Ltd.

  19. Complete Genome Sequence of Bradyrhizobium sp. S23321: Insights into Symbiosis Evolution in Soil Oligotrophs

    PubMed Central

    Okubo, Takashi; Tsukui, Takahiro; Maita, Hiroko; Okamoto, Shinobu; Oshima, Kenshiro; Fujisawa, Takatomo; Saito, Akihiro; Futamata, Hiroyuki; Hattori, Reiko; Shimomura, Yumi; Haruta, Shin; Morimoto, Sho; Wang, Yong; Sakai, Yoriko; Hattori, Masahira; Aizawa, Shin-ichi; Nagashima, Kenji V. P.; Masuda, Sachiko; Hattori, Tsutomu; Yamashita, Akifumi; Bao, Zhihua; Hayatsu, Masahito; Kajiya-Kanegae, Hiromi; Yoshinaga, Ikuo; Sakamoto, Kazunori; Toyota, Koki; Nakao, Mitsuteru; Kohara, Mitsuyo; Anda, Mizue; Niwa, Rieko; Jung-Hwan, Park; Sameshima-Saito, Reiko; Tokuda, Shin-ichi; Yamamoto, Sumiko; Yamamoto, Syuji; Yokoyama, Tadashi; Akutsu, Tomoko; Nakamura, Yasukazu; Nakahira-Yanaka, Yuka; Hoshino, Yuko Takada; Hirakawa, Hideki; Mitsui, Hisayuki; Terasawa, Kimihiro; Itakura, Manabu; Sato, Shusei; Ikeda-Ohtsubo, Wakako; Sakakura, Natsuko; Kaminuma, Eli; Minamisawa, Kiwamu

    2012-01-01

    Bradyrhizobium sp. S23321 is an oligotrophic bacterium isolated from paddy field soil. Although S23321 is phylogenetically close to Bradyrhizobium japonicum USDA110, a legume symbiont, it is unable to induce root nodules in siratro, a legume often used for testing Nod factor-dependent nodulation. The genome of S23321 is a single circular chromosome, 7,231,841 bp in length, with an average GC content of 64.3%. The genome contains 6,898 potential protein-encoding genes, one set of rRNA genes, and 45 tRNA genes. Comparison of the genome structure between S23321 and USDA110 showed strong colinearity; however, the symbiosis islands present in USDA110 were absent in S23321, whose genome lacked a chaperonin gene cluster (groELS3) for symbiosis regulation found in USDA110. A comparison of sequences around the tRNA-Val gene strongly suggested that S23321 contains an ancestral-type genome that precedes the acquisition of a symbiosis island by horizontal gene transfer. Although S23321 contains a nif (nitrogen fixation) gene cluster, the organization, homology, and phylogeny of the genes in this cluster were more similar to those of photosynthetic bradyrhizobia ORS278 and BTAi1 than to those on the symbiosis island of USDA110. In addition, we found genes encoding a complete photosynthetic system, many ABC transporters for amino acids and oligopeptides, two types (polar and lateral) of flagella, multiple respiratory chains, and a system for lignin monomer catabolism in the S23321 genome. These features suggest that S23321 is able to adapt to a wide range of environments, probably including low-nutrient conditions, with multiple survival strategies in soil and rhizosphere. PMID:22452844

  20. The role of fungal symbiosis in the adaptation of plants to high stress environments

    USGS Publications Warehouse

    Rodriguez, Russell J.; Redman, Regina S.; Henson, Joan M.

    2004-01-01

    All plants studied in natural ecosystemsare symbiotic with fungi that either resideentirely (endophytes) or partially(mycorrhizae) within plants. Thesesymbioses appear to adapt to biotic andabiotic stresses and may be responsible forthe survival of both plant hosts and fungalsymbionts in high stress habitats. Here wedescribe the role of symbiotic fungi inplant stress tolerance and present astrategy based on adaptive symbiosis topotentially mitigate the impacts of globalchange on plant communities.

  1. Insights on the Impact of Arbuscular Mycorrhizal Symbiosis on Tomato Tolerance to Water Stress.

    PubMed

    Chitarra, Walter; Pagliarani, Chiara; Maserti, Biancaelena; Lumini, Erica; Siciliano, Ilenia; Cascone, Pasquale; Schubert, Andrea; Gambino, Giorgio; Balestrini, Raffaella; Guerrieri, Emilio

    2016-06-01

    Arbuscular mycorrhizal (AM) fungi, which form symbioses with the roots of the most important crop species, are usually considered biofertilizers, whose exploitation could represent a promising avenue for the development in the future of a more sustainable next-generation agriculture. The best understood function in symbiosis is an improvement in plant mineral nutrient acquisition, as exchange for carbon compounds derived from the photosynthetic process: this can enhance host growth and tolerance to environmental stresses, such as water stress (WS). However, physiological and molecular mechanisms occurring in arbuscular mycorrhiza-colonized plants and directly involved in the mitigation of WS effects need to be further investigated. The main goal of this work is to verify the potential impact of AM symbiosis on the plant response to WS To this aim, the effect of two AM fungi (Funneliformis mosseae and Rhizophagus intraradices) on tomato (Solanum lycopersicum) under the WS condition was studied. A combined approach, involving ecophysiological, morphometric, biochemical, and molecular analyses, has been used to highlight the mechanisms involved in plant response to WS during AM symbiosis. Gene expression analyses focused on a set of target genes putatively involved in the plant response to drought, and in parallel, we considered the expression changes induced by the imposed stress on a group of fungal genes playing a key role in the water-transport process. Taken together, the results show that AM symbiosis positively affects the tolerance to WS in tomato, with a different plant response depending on the AM fungi species involved. © 2016 American Society of Plant Biologists. All Rights Reserved.

  2. Symbiosis: American Foreign Policy in the Post-Cold War Era

    DTIC Science & Technology

    2001-01-01

    world power, so the history of international relations charts the transformation of the international order from the central control of the emperor to the...so the history of international relations charts the transformation of the international order from the central control of the emperor to the...international order from the central control of the emperor to the emergence of political concepts. Accordingly, the roots of Symbiosis are planted in

  3. The Genome of Laccaria Bi color Provides Insights into Mycorrhizal Symbiosis

    SciTech Connect

    Martin, F; Aerts, A.; Ahren, D; Brun, A; Duchaussoy, F; Gibon, J; Kohler, A; Lindquist, E; Pereda, V; Salamov, A.; Shapiro, HJ; Wuyts, J; Blaudez, D; Buee, M; Brokstein, P; Canbeck, B; Cohen, D; Courty, PE; Coutinho, PM; Danchin, E; Delaruelle, C; Detter, J C; Deveau, A; DiFazio, Stephen P; Duplessis, S; Fraissinet-Tachet, L; Lucic, E; Frey-Klett, P; Fourrey, C; Feussner, I; Gay, G; Grimwood, Jane; Hoegger, P J; Jain, P; Kilaru, S; Labbe, J; Lin, Y C; Legue, V; Le Tacon, F; Marmeisse, R; Melayah, D; Montanini, B; Muratet, M; Nehls, U; Niculita-Hirzel, H; Oudot-Le Secq, M P; Peter, M; Quesneville, H; Rajashekar, B; Reich, M; Rouhler, N; Schmutz, Jeremy; Yin, Tongming; Chalot, M; Henrissat, B; Kues, U; Lucas, S; Van de Peer, Y; Podila, G; Polle, A; Pukkila, P J; Richardson, P M; Rouze, P; Sanders, I R; Stajich, J E; Tunlid, A; Tuskan, Gerald A; Grigoriev, I.

    2008-01-01

    Mycorrhizal symbioses the union of roots and soil fungi are universal in terrestrial ecosystems and may have been fundamental to land colonization by plants1,2. Boreal, temperate and montane forests all depend on ectomycorrhizae1. Identification of the primary factors that regulate symbiotic development and metabolic activity will therefore open the door to understanding the role of ectomycorrhizae in plant development and physiology, allowing the full ecological significance of this symbiosis to be explored. Here we report the genome sequence of the ectomycorrhizal basidiomycete Laccaria bicolor (Fig. 1) and highlight gene sets involved in rhizosphere colonization and symbiosis. This 65-megabase genome assembly contains 20,000 predicted protein-encoding genes and a very large number of transposons and repeated sequences. We detected unexpected genomic features, most notably a battery of effector-type small secreted proteins (SSPs) with unknown function, several of which are only expressed in symbiotic tissues. The most highly expressed SSP accumulates in the proliferating hyphae colonizing the host root. The ectomycorrhizae-specific SSPs probably have a decisive role in the establishment of the symbiosis. The unexpected observation that the genome of L. bicolor lacks carbohydrate-active enzymes involved in degradation of plant cell walls, but maintains the ability to degrade non-plant cell wall polysaccharides, reveals the dual saprotrophic and biotrophic lifestyle of the mycorrhizal fungus that enables it to grow within both soil and living plant roots. The predicted gene inventory of the L. bicolor genome, therefore, points to previously unknown mechanisms of symbiosis operating in biotrophic mycorrhizal fungi. The availability of this genome provides an unparalleled opportunity to develop a deeper understanding of the processes by which symbionts interact with plants within their ecosystem to perform vital functions in the carbon and

  4. Assess suitability of hydroaeroponic culture to establish tripartite symbiosis between different AMF species, beans, and rhizobia

    PubMed Central

    Tajini, Fatma; Suriyakup, Porntip; Vailhe, Hélène; Jansa, Jan; Drevon, Jean-Jacques

    2009-01-01

    Background Like other species of the Phaseoleae tribe, common bean (Phaseolus vulgaris L.) has the potential to establish symbiosis with rhizobia and to fix the atmospheric dinitrogen (N2) for its N nutrition. Common bean has also the potential to establish symbiosis with arbuscular mycorrhizal fungi (AMF) that improves the uptake of low mobile nutrients such as phosphorus, from the soil. Both rhizobial and mycorrhizal symbioses can act synergistically in benefits on plant. Results The tripartite symbiosis of common bean with rhizobia and arbuscular mycorrhizal fungi (AMF) was assessed in hydroaeroponic culture with common bean (Phaseolus vulgaris L.), by comparing the effects of three fungi spp. on growth, nodulation and mycorrhization of the roots under sufficient versus deficient P supplies, after transfer from initial sand culture. Although Glomus intraradices Schenck & Smith colonized intensely the roots of common bean in both sand and hydroaeroponic cultures, Gigaspora rosea Nicolson & Schenck only established well under sand culture conditions, and no root-colonization was found with Acaulospora mellea Spain & Schenck under either culture conditions. Interestingly, mycorrhization by Glomus was also obtained by contact with mycorrhized Stylosanthes guianensis (Aubl.) sw in sand culture under deficient P before transfer into hydroaeroponic culture. The effect of bean genotype on both rhizobial and mycorrhizal symbioses with Glomus was subsequently assessed with the common bean recombinant inbreed line 7, 28, 83, 115 and 147, and the cultivar Flamingo. Significant differences among colonization and nodulation of the roots and growth among genotypes were found. Conclusion The hydroaeroponic culture is a valuable tool for further scrutinizing the physiological interactions and nutrient partitioning within the tripartite symbiosis. PMID:19534785

  5. Oak Root Response to Ectomycorrhizal Symbiosis Establishment: RNA-Seq Derived Transcript Identification and Expression Profiling

    PubMed Central

    Lino-Neto, Teresa; Monteiro, Filipa; Figueiredo, Andreia; Sousa, Lisete; Pais, Maria Salomé; Tavares, Rui; Paulo, Octávio S.

    2014-01-01

    Ectomycorrhizal symbiosis is essential for the life and health of trees in temperate and boreal forests where it plays a major role in nutrient cycling and in functioning of the forest ecosystem. Trees with ectomycorrhizal root tips are more tolerant to environmental stresses, such as drought, and biotic stresses such as root pathogens. Detailed information on these molecular processes is essential for the understanding of symbiotic tissue development in order to optimize the benefits of this natural phenomenon. Next generation sequencing tools allow the analysis of non model ectomycorrhizal plant-fungal interactions that can contribute to find the “symbiosis toolkits” and better define the role of each partner in the mutualistic interaction. By using 454 pyrosequencing we compared ectomycorrhizal cork oak roots with non-symbiotic roots. From the two cDNA libraries sequenced, over 2 million reads were obtained that generated 19552 cork oak root unique transcripts. A total of 2238 transcripts were found to be differentially expressed when ECM roots were compared with non-symbiotic roots. Identification of up- and down-regulated gens in ectomycorrhizal roots lead to a number of insights into the molecular mechanisms governing this important symbiosis. In cork oak roots, ectomycorrhizal colonization resulted in extensive cell wall remodelling, activation of the secretory pathway, alterations in flavonoid biosynthesis, and expression of genes involved in the recognition of fungal effectors. In addition, we identified genes with putative roles in symbiotic processes such as nutrient exchange with the fungal partner, lateral root formation or root hair decay. These findings provide a global overview of the transcriptome of an ectomycorrhizal host root, and constitute a foundation for future studies on the molecular events controlling this important symbiosis. PMID:24859293

  6. [Signal exchange between plants and Arbuscular Mycorrhizae fungi during the early stage of symbiosis - A review].

    PubMed

    Duan, Qianqian; Yang, Xiaohong; Huang, Xianzhi

    2015-07-04

    Much is known about Arbuscular Mycorrhizae (AM), an important component of the ecosystem, whereas little is known about the signal exchange that allows mutual recognition and reprograming for the anticipated physical interaction. This review addresses the latest advances of signal exchange between plants and AM, including signal substances and their function, related genes and regulation function in the early stage of plant-fungal symbiosis.

  7. Development and Symbiosis Establishment in the Cnidarian Endosymbiosis Model Aiptasia sp.

    PubMed

    Bucher, Madeline; Wolfowicz, Iliona; Voss, Philipp A; Hambleton, Elizabeth A; Guse, Annika

    2016-01-25

    Symbiosis between photosynthetic algae and heterotrophic organisms is widespread. One prominent example of high ecological relevance is the endosymbiosis between dinoflagellate algae of the genus Symbiodinium and reef-building corals, which typically acquire symbionts anew each generation during larval stages. The tropical sea anemone Aiptasia sp. is a laboratory model system for this endosymbiosis and, similar to corals, produces non-symbiotic larvae that establish symbiosis by phagocytosing Symbiodinium from the environment into the endoderm. Here we generate the first overview of Aiptasia embryogenesis and larval development and establish in situ hybridization to analyze expression patterns of key early developmental regulators. Next, we quantify morphological changes in developing larvae and find a substantial enlargement of the gastric cavity over time. Symbiont acquisition starts soon after mouth formation and symbionts occupy a major portion of the host cell in which they reside. During the first 14 days of development, infection efficiency remains constant while in contrast, localization of phagocytosed symbionts changes, indicating that the occurrence of functional phagocytosing cells may be developmentally regulated. Taken together, here we provide the essential framework to further develop Aiptasia as a model system for the analysis of symbiosis establishment in cnidarian larvae at the molecular level.

  8. Something old, something new: auxin and strigolactone interact in the ancient mycorrhizal symbiosis.

    PubMed

    Foo, Eloise

    2013-04-01

    Arbuscular mycorrhizal symbiosis, formed between more than 80% of land plants and fungi from the phylum Glomeromycota, is an ancient association that is believed to have evolved as plants moved onto land more than 400 mya. Similarly ancient, the plant hormones auxin and strigolactone are thought to have been present in the plant lineage since before the divergence of the bryophytes in the case of auxin and before the colonisation of land in the case of strigolactones. The discovery of auxin in the 1930s predates the discovery of strigolactones as a plant hormone in 2008 by over 70 y. Recent studies in pea suggest that these two signals may interact to regulate mycorrhizal symbiosis. Furthermore, the first quantitative studies are presented that show that low auxin content of the root is correlated with low strigolactone production, an interaction that has implications for how these plant hormones regulate several developmental programs including shoot branching, secondary growth and root development. With recent advances in our understanding of auxin and strigolactone biosynthesis, together with the discovery of the fungal signals that activate the plant host, the stage is set for real breakthroughs in our understanding of the interactions between plant and fungal signals in mycorrhizal symbiosis.

  9. Hydrogen peroxide-regulated genes in the Medicago truncatula-Sinorhizobium meliloti symbiosis.

    PubMed

    Andrio, Emilie; Marino, Daniel; Marmeys, Anthony; de Segonzac, Marion Dunoyer; Damiani, Isabelle; Genre, Andrea; Huguet, Stéphanie; Frendo, Pierre; Puppo, Alain; Pauly, Nicolas

    2013-04-01

    Reactive oxygen species (ROS), particularly hydrogen peroxide (H(2)O(2)), play an important role in signalling in various cellular processes. The involvement of H(2)O(2) in the Medicago truncatula-Sinorhizobium meliloti symbiotic interaction raises questions about its effect on gene expression. A transcriptome analysis was performed on inoculated roots of M. truncatula in which ROS production was inhibited with diphenylene iodonium (DPI). In total, 301 genes potentially regulated by ROS content were identified 2 d after inoculation. These genes included MtSpk1, which encodes a putative protein kinase and is induced by exogenous H(2)O(2) treatment. MtSpk1 gene expression was also induced by nodulation factor treatment. MtSpk1 transcription was observed in infected root hair cells, nodule primordia and the infection zone of mature nodules. Analysis with a fluorescent protein probe specific for H(2)O(2) showed that MtSpk1 expression and H(2)O(2) were similarly distributed in the nodule infection zone. Finally, the establishment of symbiosis was impaired by MtSpk1 downregulation with an artificial micro-RNA. Several genes regulated by H(2)O(2) during the establishment of rhizobial symbiosis were identified. The involvement of MtSpk1 in the establishment of the symbiosis is proposed. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  10. Do the costs and benefits of fungal endophyte symbiosis vary with light availability?

    PubMed

    Davitt, Andrew J; Stansberry, Marcus; Rudgers, Jennifer A

    2010-11-01

    • Here, we examined whether fungal endophytes modulated host plant responses to light availability. First, we conducted a literature review to evaluate whether natural frequencies of endophyte symbiosis in grasses from shaded habitats were higher than frequencies in grasses occupying more diverse light environments. Then, in a glasshouse experiment, we assessed how four levels of light and the presence of endophyte symbioses affected the growth of six grass species. • In our literature survey, endophytes were more commonly present in grasses restricted to shaded habitats than in grasses from diverse light environments. • In the glasshouse, endophyte symbioses did not mediate plant growth in response to light availability. However, in the host grass, Agrostis perennans, symbiotic plants produced 53% more inflorescences than nonsymbiotic plants at the highest level of shade. In addition, under high shade, symbiotic Poa autumnalis invested more in specific leaf area than symbiont-free plants. Finally, shade increased the density of the endophyte in leaf tissues across all six grass species. • Our results highlight the potential for symbiosis to alter the plasticity of host physiological traits, demonstrate a novel benefit of endophyte symbiosis under shade stress for one host species, and show a positive association between shade-restricted grass species and fungal endophytes.

  11. Role of arbuscular mycorrhizal symbiosis in root mineral uptake under CaCO3 stress.

    PubMed

    Labidi, Sonia; Ben Jeddi, Fayçal; Tisserant, Benoit; Debiane, Djouher; Rezgui, Salah; Grandmougin-Ferjani, Anne; Lounès-Hadj Sahraoui, Anissa

    2012-07-01

    This study investigated the effects of increasing CaCO(3) concentrations (0, 5, 10, 20 mM) on arbuscular mycorrhizal (AM) symbiosis establishment as well as on chicory root growth and mineral nutrient uptake in a monoxenic system. Although CaCO(3) treatments significantly decreased root growth and altered the symbiosis-related development steps of the AM fungus Rhizophagus irregularis (germination, germination hypha elongation, root colonization rate, extraradical hyphal development, sporulation), the fungus was able to completely fulfill its life cycle. Even when root growth decreased more drastically in mycorrhizal roots than in non-mycorrhizal ones in the presence of high CaCO(3) levels, the AM symbiosis was found to be beneficial for root mineral uptake. Significant increases in P, N, Fe, Zn and Cu concentrations were recorded in the mycorrhizal roots. Whereas acid and alkaline phosphatase enzymatic activities remained constant in mycorrhizal roots, they were affected in non-mycorrhizal roots grown in the presence of CaCO(3) when compared with the control.

  12. The regulation of arbuscular mycorrhizal symbiosis by phosphate in pea involves early and systemic signalling events.

    PubMed

    Balzergue, Coline; Puech-Pagès, Virginie; Bécard, Guillaume; Rochange, Soizic F

    2011-01-01

    Most plants form root symbioses with arbuscular mycorrhizal (AM) fungi, which provide them with phosphate and other nutrients. High soil phosphate levels are known to affect AM symbiosis negatively, but the underlying mechanisms are not understood. This report describes experimental conditions which triggered a novel mycorrhizal phenotype under high phosphate supply: the interaction between pea and two different AM fungi was almost completely abolished at a very early stage, prior to the formation of hyphopodia. As demonstrated by split-root experiments, down-regulation of AM symbiosis occurred at least partly in response to plant-derived signals. Early signalling events were examined with a focus on strigolactones, compounds which stimulate pre-symbiotic fungal growth and metabolism. Strigolactones were also recently identified as novel plant hormones contributing to the control of shoot branching. Root exudates of plants grown under high phosphate lost their ability to stimulate AM fungi and lacked strigolactones. In addition, a systemic down-regulation of strigolactone release by high phosphate supply was demonstrated using split-root systems. Nevertheless, supplementation with exogenous strigolactones failed to restore root colonization under high phosphate. This observation does not exclude a contribution of strigolactones to the regulation of AM symbiosis by phosphate, but indicates that they are not the only factor involved. Together, the results suggest the existence of additional early signals that may control the differentiation of hyphopodia.

  13. Large-Scale Label-Free Quantitative Proteomics of the Pea aphid-Buchnera Symbiosis*

    PubMed Central

    Poliakov, Anton; Russell, Calum W.; Ponnala, Lalit; Hoops, Harold J.; Sun, Qi; Douglas, Angela E.; van Wijk, Klaas J.

    2011-01-01

    Many insects are nutritionally dependent on symbiotic microorganisms that have tiny genomes and are housed in specialized host cells called bacteriocytes. The obligate symbiosis between the pea aphid Acyrthosiphon pisum and the γ-proteobacterium Buchnera aphidicola (only 584 predicted proteins) is particularly amenable for molecular analysis because the genomes of both partners have been sequenced. To better define the symbiotic relationship between this aphid and Buchnera, we used large-scale, high accuracy tandem mass spectrometry (nanoLC-LTQ-Orbtrap) to identify aphid and Buchnera proteins in the whole aphid body, purified bacteriocytes, isolated Buchnera cells and the residual bacteriocyte fraction. More than 1900 aphid and 400 Buchnera proteins were identified. All enzymes in amino acid metabolism annotated in the Buchnera genome were detected, reflecting the high (68%) coverage of the proteome and supporting the core function of Buchnera in the aphid symbiosis. Transporters mediating the transport of predicted metabolites were present in the bacteriocyte. Label-free spectral counting combined with hierarchical clustering, allowed to define the quantitative distribution of a subset of these proteins across both symbiotic partners, yielding no evidence for the selective transfer of protein among the partners in either direction. This is the first quantitative proteome analysis of bacteriocyte symbiosis, providing a wealth of information about molecular function of both the host cell and bacterial symbiont. PMID:21421797

  14. Burkholderia bacteria infectiously induce the proto-farming symbiosis of Dictyostelium amoebae and food bacteria.

    PubMed

    DiSalvo, Susanne; Haselkorn, Tamara S; Bashir, Usman; Jimenez, Daniela; Brock, Debra A; Queller, David C; Strassmann, Joan E

    2015-09-08

    Symbiotic associations can allow an organism to acquire novel traits by accessing the genetic repertoire of its partner. In the Dictyostelium discoideum farming symbiosis, certain amoebas (termed "farmers") stably associate with bacterial partners. Farmers can suffer a reproductive cost but also gain beneficial capabilities, such as carriage of bacterial food (proto-farming) and defense against competitors. Farming status previously has been attributed to amoeba genotype, but the role of bacterial partners in its induction has not been examined. Here, we explore the role of bacterial associates in the initiation, maintenance, and phenotypic effects of the farming symbiosis. We demonstrate that two clades of farmer-associated Burkholderia isolates colonize D. discoideum nonfarmers and infectiously endow them with farmer-like characteristics, indicating that Burkholderia symbionts are a major driver of the farming phenomenon. Under food-rich conditions, Burkholderia-colonized amoebas produce fewer spores than uncolonized counterparts, with the severity of this reduction being dependent on the Burkholderia colonizer. However, the induction of food carriage by Burkholderia colonization may be considered a conditionally adaptive trait because it can confer an advantage to the amoeba host when grown in food-limiting conditions. We observed Burkholderia inside and outside colonized D. discoideum spores after fruiting body formation; this observation, together with the ability of Burkholderia to colonize new amoebas, suggests a mixed mode of symbiont transmission. These results change our understanding of the D. discoideum farming symbiosis by establishing that the bacterial partner, Burkholderia, is an important causative agent of the farming phenomenon.

  15. [Metabolism and interaction of C and N in the arbuscular mycorrhizal symbiosis].

    PubMed

    Li, Yuan-Jing; Liu, Zhi-Lei; He, Xing-Yuan; Tian, Chun-Jie

    2014-03-01

    The arbuscular mycorrhiza (AM) is the symbiont formed by the host plant and the arbuscular mycorrhizal fungi (AMF). The transfer and metabolism of C and N in the symbiosis plays an important role in keeping nutrient balance and resource reallocation between the host plant and the fungi. The carbohydrates produced by plant photosynthesis are transferred to the fungi, where they are metabolized as materials and energy used for fungal spore germination, mycelium growth and uptake of nitrogen and other nutrients. At the same time, N is transferred and reallocated from the fungi to the host plant, where the final released ammonium is used for plant growth. Accordingly, we reviewed the current progress in C and N transfer and metabolism in the AM symbiosis, and the crosstalk between them as well as some key issues to elucidate the mechanism of the interaction between C and N transport in the symbiosis, so as to provide the theory foundation for the application of AM in sustainable agriculture and ecosystem.

  16. Multi-gene analysis of Symbiodinium dinoflagellates: a perspective on rarity, symbiosis, and evolution.

    PubMed

    Pochon, Xavier; Putnam, Hollie M; Gates, Ruth D

    2014-01-01

    Symbiodinium, a large group of dinoflagellates, live in symbiosis with marine protists, invertebrate metazoans, and free-living in the environment. Symbiodinium are functionally variable and play critical energetic roles in symbiosis. Our knowledge of Symbiodinium has been historically constrained by the limited number of molecular markers available to study evolution in the genus. Here we compare six functional genes, representing three cellular compartments, in the nine known Symbiodinium lineages. Despite striking similarities among the single gene phylogenies from distinct organelles, none were evolutionarily identical. A fully concatenated reconstruction, however, yielded a well-resolved topology identical to the current benchmark nr28S gene. Evolutionary rates differed among cellular compartments and clades, a pattern largely driven by higher rates of evolution in the chloroplast genes of Symbiodinium clades D2 and I. The rapid rates of evolution observed amongst these relatively uncommon Symbiodinium lineages in the functionally critical chloroplast may translate into potential innovation for the symbiosis. The multi-gene analysis highlights the potential power of assessing genome-wide evolutionary patterns using recent advances in sequencing technology and emphasizes the importance of integrating ecological data with more comprehensive sampling of free-living and symbiotic Symbiodinium in assessing the evolutionary adaptation of this enigmatic dinoflagellate.

  17. Symbiont-driven sulfur crystal formation in a thiotrophic symbiosis from deep-sea hydrocarbon seeps

    PubMed Central

    Eichinger, Irmgard; Schmitz-Esser, Stephan; Schmid, Markus; Fisher, Charles R; Bright, Monika

    2014-01-01

    The siboglinid tubeworm Sclerolinum contortum symbiosis inhabits sulfidic sediments at deep-sea hydrocarbon seeps in the Gulf of Mexico. A single symbiont phylotype in the symbiont-housing organ is inferred from phylogenetic analyses of the 16S ribosomal ribonucleic acid (16S rRNA) gene and fluorescent in situ hybridization. The phylotype we studied here, and a previous study from an arctic hydrocarbon seep population, reveal identical 16S rRNA symbiont gene sequences. While sulfide is apparently the energy source for the symbionts (and ultimately the gutless host), both partners also have to cope with its toxicity. This study demonstrates abundant large sulfur crystals restricted to the trophosome area. Based on Raman microspectroscopy and energy dispersive X-ray analysis, these crystals have the same S8 sulfur configuration as the recently described small sulfur vesicles formed in the symbionts. The crystals reside adjacent to the symbionts in the trophosome. This suggests that their formation is either extra- or intracellular in symbionts. We propose that formation of these crystals provides both energy-storage compounds for the symbionts and serves the symbiosis by removing excess toxic sulfide from host tissues. This symbiont-mediated sulfide detoxification may have been crucial for the establishment of thiotrophic symbiosis and continues to remain an important function of the symbionts. PMID:24992535

  18. Complex microbiome underlying secondary and primary metabolism in the tunicate-Prochloron symbiosis.

    PubMed

    Donia, Mohamed S; Fricke, W Florian; Partensky, Frédéric; Cox, James; Elshahawi, Sherif I; White, James R; Phillippy, Adam M; Schatz, Michael C; Piel, Joern; Haygood, Margo G; Ravel, Jacques; Schmidt, Eric W

    2011-12-20

    The relationship between tunicates and the uncultivated cyanobacterium Prochloron didemni has long provided a model symbiosis. P. didemni is required for survival of animals such as Lissoclinum patella and also makes secondary metabolites of pharmaceutical interest. Here, we present the metagenomes, chemistry, and microbiomes of four related L. patella tunicate samples from a wide geographical range of the tropical Pacific. The remarkably similar P. didemni genomes are the most complex so far assembled from uncultivated organisms. Although P. didemni has not been stably cultivated and comprises a single strain in each sample, a complete set of metabolic genes indicates that the bacteria are likely capable of reproducing outside the host. The sequences reveal notable peculiarities of the photosynthetic apparatus and explain the basis of nutrient exchange underlying the symbiosis. P. didemni likely profoundly influences the lipid composition of the animals by synthesizing sterols and an unusual lipid with biofuel potential. In addition, L. patella also harbors a great variety of other bacterial groups that contribute nutritional and secondary metabolic products to the symbiosis. These bacteria possess an enormous genetic potential to synthesize new secondary metabolites. For example, an antitumor candidate molecule, patellazole, is not encoded in the genome of Prochloron and was linked to other bacteria from the microbiome. This study unveils the complex L. patella microbiome and its impact on primary and secondary metabolism, revealing a remarkable versatility in creating and exchanging small molecules.

  19. Development and Symbiosis Establishment in the Cnidarian Endosymbiosis Model Aiptasia sp.

    PubMed Central

    Bucher, Madeline; Wolfowicz, Iliona; Voss, Philipp A.; Hambleton, Elizabeth A.; Guse, Annika

    2016-01-01

    Symbiosis between photosynthetic algae and heterotrophic organisms is widespread. One prominent example of high ecological relevance is the endosymbiosis between dinoflagellate algae of the genus Symbiodinium and reef-building corals, which typically acquire symbionts anew each generation during larval stages. The tropical sea anemone Aiptasia sp. is a laboratory model system for this endosymbiosis and, similar to corals, produces non-symbiotic larvae that establish symbiosis by phagocytosing Symbiodinium from the environment into the endoderm. Here we generate the first overview of Aiptasia embryogenesis and larval development and establish in situ hybridization to analyze expression patterns of key early developmental regulators. Next, we quantify morphological changes in developing larvae and find a substantial enlargement of the gastric cavity over time. Symbiont acquisition starts soon after mouth formation and symbionts occupy a major portion of the host cell in which they reside. During the first 14 days of development, infection efficiency remains constant while in contrast, localization of phagocytosed symbionts changes, indicating that the occurrence of functional phagocytosing cells may be developmentally regulated. Taken together, here we provide the essential framework to further develop Aiptasia as a model system for the analysis of symbiosis establishment in cnidarian larvae at the molecular level. PMID:26804034

  20. The regulation of arbuscular mycorrhizal symbiosis by phosphate in pea involves early and systemic signalling events

    PubMed Central

    Balzergue, Coline; Puech-Pagès, Virginie; Bécard, Guillaume; Rochange, Soizic F.

    2011-01-01

    Most plants form root symbioses with arbuscular mycorrhizal (AM) fungi, which provide them with phosphate and other nutrients. High soil phosphate levels are known to affect AM symbiosis negatively, but the underlying mechanisms are not understood. This report describes experimental conditions which triggered a novel mycorrhizal phenotype under high phosphate supply: the interaction between pea and two different AM fungi was almost completely abolished at a very early stage, prior to the formation of hyphopodia. As demonstrated by split-root experiments, down-regulation of AM symbiosis occurred at least partly in response to plant-derived signals. Early signalling events were examined with a focus on strigolactones, compounds which stimulate pre-symbiotic fungal growth and metabolism. Strigolactones were also recently identified as novel plant hormones contributing to the control of shoot branching. Root exudates of plants grown under high phosphate lost their ability to stimulate AM fungi and lacked strigolactones. In addition, a systemic down-regulation of strigolactone release by high phosphate supply was demonstrated using split-root systems. Nevertheless, supplementation with exogenous strigolactones failed to restore root colonization under high phosphate. This observation does not exclude a contribution of strigolactones to the regulation of AM symbiosis by phosphate, but indicates that they are not the only factor involved. Together, the results suggest the existence of additional early signals that may control the differentiation of hyphopodia. PMID:21045005

  1. Use of carbon monoxide and hydrogen by a bacteria–animal symbiosis from seagrass sediments

    PubMed Central

    Holler, Thomas; Lavik, Gaute; Harder, Jens; Lott, Christian; Littmann, Sten; Kuypers, Marcel M. M.; Dubilier, Nicole

    2015-01-01

    Summary The gutless marine worm O lavius algarvensis lives in symbiosis with chemosynthetic bacteria that provide nutrition by fixing carbon dioxide (CO 2) into biomass using reduced sulfur compounds as energy sources. A recent metaproteomic analysis of the O . algarvensis symbiosis indicated that carbon monoxide (CO) and hydrogen (H 2) might also be used as energy sources. We provide direct evidence that the O . algarvensis symbiosis consumes CO and H 2. Single cell imaging using nanoscale secondary ion mass spectrometry revealed that one of the symbionts, the γ3‐symbiont, uses the energy from CO oxidation to fix CO 2. Pore water analysis revealed considerable in‐situ concentrations of CO and H 2 in the O . algarvensis environment, Mediterranean seagrass sediments. Pore water H 2 concentrations (89–2147 nM) were up to two orders of magnitude higher than in seawater, and up to 36‐fold higher than previously known from shallow‐water marine sediments. Pore water CO concentrations (17–51 nM) were twice as high as in the overlying seawater (no literature data from other shallow‐water sediments are available for comparison). Ex‐situ incubation experiments showed that dead seagrass rhizomes produced large amounts of CO. CO production from decaying plant material could thus be a significant energy source for microbial primary production in seagrass sediments. PMID:26013766

  2. Use of carbon monoxide and hydrogen by a bacteria-animal symbiosis from seagrass sediments.

    PubMed

    Kleiner, Manuel; Wentrup, Cecilia; Holler, Thomas; Lavik, Gaute; Harder, Jens; Lott, Christian; Littmann, Sten; Kuypers, Marcel M M; Dubilier, Nicole

    2015-12-01

    The gutless marine worm Olavius algarvensis lives in symbiosis with chemosynthetic bacteria that provide nutrition by fixing carbon dioxide (CO2 ) into biomass using reduced sulfur compounds as energy sources. A recent metaproteomic analysis of the O. algarvensis symbiosis indicated that carbon monoxide (CO) and hydrogen (H2 ) might also be used as energy sources. We provide direct evidence that the O. algarvensis symbiosis consumes CO and H2 . Single cell imaging using nanoscale secondary ion mass spectrometry revealed that one of the symbionts, the γ3-symbiont, uses the energy from CO oxidation to fix CO2 . Pore water analysis revealed considerable in-situ concentrations of CO and H2 in the O. algarvensis environment, Mediterranean seagrass sediments. Pore water H2 concentrations (89-2147 nM) were up to two orders of magnitude higher than in seawater, and up to 36-fold higher than previously known from shallow-water marine sediments. Pore water CO concentrations (17-51 nM) were twice as high as in the overlying seawater (no literature data from other shallow-water sediments are available for comparison). Ex-situ incubation experiments showed that dead seagrass rhizomes produced large amounts of CO. CO production from decaying plant material could thus be a significant energy source for microbial primary production in seagrass sediments.

  3. Fungal and algal gene expression in early developmental stages of lichen-symbiosis.

    PubMed

    Joneson, Suzanne; Armaleo, Daniele; Lutzoni, François

    2011-01-01

    How plants and microbes recognize each other and interact to form long-lasting relationships remains one of the central questions in cellular communication. The symbiosis between the filamentous fungus Cladonia grayi and the single-celled green alga Asterochloris sp. was used to determine fungal and algal genes upregulated in vitro in early lichen development. cDNA libraries of upregulated genes were created with suppression subtractive hybridization in the first two stages of lichen development. Quantitative PCR subsequently was used to verify the expression level of 41 and 33 candidate fungal and algal genes respectively. Induced fungal genes showed significant matches to genes putatively encoding proteins involved in self and non-self recognition, lipid metabolism, and negative regulation of glucose repressible genes, as well as to a putative d-arabitol reductase and two dioxygenases. Upregulated algal genes included a chitinase-like protein, an amino acid metabolism protein, a dynein-related protein and a protein arginine methyltransferase. These results also provided the first evidence that extracellular communication without cellular contact can occur between lichen symbionts. Many genes showing slight variation in expression appear to direct the development of the lichen symbiosis. The results of this study highlight future avenues of investigation into the molecular biology of lichen symbiosis.

  4. Multi-gene analysis of Symbiodinium dinoflagellates: a perspective on rarity, symbiosis, and evolution

    PubMed Central

    Putnam, Hollie M.; Gates, Ruth D.

    2014-01-01

    Symbiodinium, a large group of dinoflagellates, live in symbiosis with marine protists, invertebrate metazoans, and free-living in the environment. Symbiodinium are functionally variable and play critical energetic roles in symbiosis. Our knowledge of Symbiodinium has been historically constrained by the limited number of molecular markers available to study evolution in the genus. Here we compare six functional genes, representing three cellular compartments, in the nine known Symbiodinium lineages. Despite striking similarities among the single gene phylogenies from distinct organelles, none were evolutionarily identical. A fully concatenated reconstruction, however, yielded a well-resolved topology identical to the current benchmark nr28S gene. Evolutionary rates differed among cellular compartments and clades, a pattern largely driven by higher rates of evolution in the chloroplast genes of Symbiodinium clades D2 and I. The rapid rates of evolution observed amongst these relatively uncommon Symbiodinium lineages in the functionally critical chloroplast may translate into potential innovation for the symbiosis. The multi-gene analysis highlights the potential power of assessing genome-wide evolutionary patterns using recent advances in sequencing technology and emphasizes the importance of integrating ecological data with more comprehensive sampling of free-living and symbiotic Symbiodinium in assessing the evolutionary adaptation of this enigmatic dinoflagellate. PMID:24883254

  5. Use of carbon monoxide and hydrogen by a bacteria-animal symbiosis from seagrass sediments

    DOE PAGES

    Kleiner, Manuel; Wentrup, Cecilia; Holler, Thomas; ...

    2015-05-27

    The gutless marine worm Olavius algarvensis lives in symbiosis with chemosynthetic bacteria that provide nutrition by fixing carbon dioxide (CO2) into biomass using reduced sulfur compounds as energy sources. A recent metaproteomic analysis of the O. algarvensis symbiosis indicated that carbon monoxide (CO) and hydrogen (H2) might also be used as energy sources. We provide direct evidence that the O. algarvensis symbiosis consumes CO and H2. Single cell imaging using nanoscale secondary ion mass spectrometry revealed that one of the symbionts, the γ3-symbiont, uses the energy from CO oxidation to fix CO2. Pore water analysis revealed considerable in-situ concentrations ofmore » CO and H2 in the O. algarvensis environment, Mediterranean seagrass sediments. Pore water H2 concentrations (89-2147 nM) were up to two orders of magnitude higher than in seawater, and up to 36-fold higher than previously known from shallow-water marine sediments. Pore water CO concentrations (17-51 nM) were twice as high as in the overlying seawater (no literature data from other shallow-water sediments are available for comparison). Ex-situ incubation experiments showed that dead seagrass rhizomes produced large amounts of CO. Lastly, CO production from decaying plant material could thus be a significant energy source for microbial primary production in seagrass sediments.« less

  6. Low host-pathogen specificity in the leaf-cutting ant-microbe symbiosis.

    PubMed

    Taerum, Stephen J; Cafaro, Matías J; Little, Ainslie E F; Schultz, Ted R; Currie, Cameron R

    2007-08-22

    Host-parasite associations are shaped by coevolutionary dynamics. One example is the complex fungus-growing ant-microbe symbiosis, which includes ancient host-parasite coevolution. Fungus-growing ants and the fungi they cultivate for food have an antagonistic symbiosis with Escovopsis, a specialized microfungus that infects the ants' fungus gardens. The evolutionary histories of the ant, cultivar and Escovopsis are highly congruent at the deepest phylogenetic levels, with specific parasite lineages exclusively associating with corresponding groups of ants and cultivar. Here, we examine host-parasite specificity at finer phylogenetic levels, within the most derived clade of fungus-growing ants, the leaf-cutters (Atta spp. and Acromyrmex spp.). Our molecular phylogeny of Escovopsis isolates from the leaf-cutter ant-microbe symbiosis confirms specificity at the broad phylogenetic level, but reveals frequent host-switching events between species and genera of leaf-cutter ants. Escovopsis strains isolated from Acromyrmex and Atta gardens occur together in the same clades, and very closely related strains can even infect the gardens of both ant genera. Experimental evidence supports low host-parasite specificity, with phylogenetically diverse strains of Escovopsis being capable of overgrowing all leaf-cutter cultivars examined. Thus, our findings indicate that this host-pathogen association is shaped by the farming ants having to protect their cultivated fungus from phylogenetically diverse Escovopsis garden pathogens.

  7. A symbiosis-dedicated SYNTAXIN OF PLANTS 13II isoform controls the formation of a stable host-microbe interface in symbiosis.

    PubMed

    Huisman, Rik; Hontelez, Jan; Mysore, Kirankumar S; Wen, Jiangqi; Bisseling, Ton; Limpens, Erik

    2016-09-01

    Arbuscular mycorrhizal (AM) fungi and rhizobium bacteria are accommodated in specialized membrane compartments that form a host-microbe interface. To better understand how these interfaces are made, we studied the regulation of exocytosis during interface formation. We used a phylogenetic approach to identify target soluble N-ethylmaleimide-sensitive factor-attachment protein receptors (t-SNAREs) that are dedicated to symbiosis and used cell-specific expression analysis together with protein localization to identify t-SNAREs that are present on the host-microbe interface in Medicago truncatula. We investigated the role of these t-SNAREs during the formation of a host-microbe interface. We showed that multiple syntaxins are present on the peri-arbuscular membrane. From these, we identified SYNTAXIN OF PLANTS 13II (SYP13II) as a t-SNARE that is essential for the formation of a stable symbiotic interface in both AM and rhizobium symbiosis. In most dicot plants, the SYP13II transcript is alternatively spliced, resulting in two isoforms, SYP13IIα and SYP13IIβ. These splice-forms differentially mark functional and degrading arbuscule branches. Our results show that vesicle traffic to the symbiotic interface is specialized and required for its maintenance. Alternative splicing of SYP13II allows plants to replace a t-SNARE involved in traffic to the plasma membrane with a t-SNARE that is more stringent in its localization to functional arbuscules.

  8. Nitric Oxide Mediates Biofilm Formation and Symbiosis in Silicibacter sp. Strain TrichCH4B.

    PubMed

    Rao, Minxi; Smith, Brian C; Marletta, Michael A

    2015-05-05

    Nitric oxide (NO) plays an important signaling role in all domains of life. Many bacteria contain a heme-nitric oxide/oxygen binding (H-NOX) protein that selectively binds NO. These H-NOX proteins often act as sensors that regulate histidine kinase (HK) activity, forming part of a bacterial two-component signaling system that also involves one or more response regulators. In several organisms, NO binding to the H-NOX protein governs bacterial biofilm formation; however, the source of NO exposure for these bacteria is unknown. In mammals, NO is generated by the enzyme nitric oxide synthase (NOS) and signals through binding the H-NOX domain of soluble guanylate cyclase. Recently, several bacterial NOS proteins have also been reported, but the corresponding bacteria do not also encode an H-NOX protein. Here, we report the first characterization of a bacterium that encodes both a NOS and H-NOX, thus resembling the mammalian system capable of both synthesizing and sensing NO. We characterized the NO signaling pathway of the marine alphaproteobacterium Silicibacter sp. strain TrichCH4B, determining that the NOS is activated by an algal symbiont, Trichodesmium erythraeum. NO signaling through a histidine kinase-response regulator two-component signaling pathway results in increased concentrations of cyclic diguanosine monophosphate, a key bacterial second messenger molecule that controls cellular adhesion and biofilm formation. Silicibacter sp. TrichCH4B biofilm formation, activated by T. erythraeum, may be an important mechanism for symbiosis between the two organisms, revealing that NO plays a previously unknown key role in bacterial communication and symbiosis. Bacterial nitric oxide (NO) signaling via heme-nitric oxide/oxygen binding (H-NOX) proteins regulates biofilm formation, playing an important role in protecting bacteria from oxidative stress and other environmental stresses. Biofilms are also an important part of symbiosis, allowing the organism to remain in a

  9. Rethinking Diet to Aid Human-Microbe Symbiosis.

    PubMed

    Derrien, Muriel; Veiga, Patrick

    2017-02-01

    The spread of the Western lifestyle has been accompanied by microbial changes thought to underlie the emergence of chronic, nontransmissible, immune-related diseases. The past decade has seen the unprecedented development of therapies for 'replenishing' the microbiota of sick individuals. However, functional and ecological solutions helping the host and the gut microbiota to cope with the ecological stressors of modern life are still lacking. In this review, we discuss how recent advances in gut microbiome science are leading to the identification of microbe-derived and health-relevant metabolites. These molecules will guide the selection of the next-generation of probiotics and dietary recommendations, which should also take the resident gut microbiota into account, to optimise efficacy. These solutions for maintaining a well-functioning gut ecosystem and promoting good health should be customised, palatable, and as widely accessible as possible. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Symbiosis--undergraduate research mentoring and faculty scholarship in nursing.

    PubMed

    Wheeler, Erlinda C; Hardie, Thomas; Schell, Kathleen; Plowfield, Lisa

    2008-01-01

    Although teaching is the major focus of academia, research and professional publications frequently determine faculty eligibility for promotion and tenure. In universities where funded research is scarce, faculty need creative means to accomplish research goals. Research is an essential part of baccalaureate nursing education. The goal of research education at the baccalaureate level is to prepare knowledgeable consumers in nursing research. The purpose of this article is to describe an undergraduate nursing research course that provide students with hands-on experience in the conduct of nursing research and provide faculty with assistance in moving their research agenda forward. Faculty members were solicited to work with 5-10 students in a research project that was either in the planning stages or actively in progress. After one year of program implementation, faculty and students were involved in presenting poster and oral presentations at state, regional, and international research conferences. Manuscripts and proposals for funding are in the process of submission.

  11. Health working with industry to promote fruit and vegetables: a case study of the Western Australian Fruit and Vegetable Campaign with reflection on effectiveness of inter-sectoral action.

    PubMed

    Miller, Margaret; Pollard, Christina

    2005-04-01

    In 1990, the Department of Health in Western Australia (DOH) initiated a five-year campaign to increase awareness of the need to eat more fruit and vegetables and to encourage increased consumption. This paper describes aspects of the campaign and reviews the strengths and weaknesses of health and fruit and vegetable industry alliances to extend and sustain the campaign. The fruit and vegetable industry was engaged through information sharing, consultation, working groups and joint promotions. The partnership was examined in terms of six inter-sectoral action dimensions (necessity; opportunity and capacity to work together; established relationships for goal achievement; degree of planning; potential for evaluation; and sustainability of action). There were both need and opportunity for each sector to work together. Health had commitment, expertise and resources to plan, implement and evaluate the campaign. Industry had established channels of communication within the supply chain. Sustained health sector presence provided incentive, endorsement and policy direction. Resources and infrastructure limited partnership sustainability. Greatest potential for success occurred when participants' contributions were closely aligned to their core business and there was a body responsible for co-ordinating action.

  12. 7 CFR 1212.20 - Promotion.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Promotion. 1212.20 Section 1212.20 Agriculture..., PROMOTION, CONSUMER EDUCATION AND INDUSTRY INFORMATION ORDER Honey Packers and Importers Research, Promotion, Consumer Education, and Industry Information Order Definitions § 1212.20 Promotion. “Promotion” means...

  13. Cooperation and collaboration between a public health unit and midsized private industry in health promotion programming: the Polymer Heart Health Program experience.

    PubMed

    Shoveller, J A; Langille, D B

    1993-01-01

    In 1990, Cobequid Health Unit was approached by Polymer International, a plastics manufacturer, and planning began for a worksite cardiovascular risk factor screening and follow-up program. In 1991, 302 Polymer employees (89.1%) participated in a screening. Follow-up included smoking cessation programs, fitness opportunities, dietary counselling, and physician referral for further investigation of blood pressure and cholesterol levels. Policy and environmental changes include heart healthy foods at the cafeteria, development of non-smoking policy, and coverage under the corporate group insurance plan for dietary counselling. This process demonstrates the potential for public health and private industry to collaborate in preventive efforts and the principles required for success.

  14. [World Population Day, July 1997. For a trilogy in symbiosis].

    PubMed

    Kefi, R

    1997-09-01

    World population growth was very slow throughout most of history, with the 1 billion mark attained only in the 19th century. Total world population reached 5.848 billion in 1997, and at a growth rate of 1.4% is expected to reach 8 billion in 2025. Over 80% of the growth occurs in developing countries. Asia, with 3.538 billion, remains the most populous continent. 1.243 billion are in China; 960 million, in India. Population growth appears to be declining everywhere in the world expect Africa, which is growing at 2.6%, and Western Asia, growing at 2.2%. The growth rate is 0.3% in industrialized countries as a whole, and 0% in Europe. The developing countries have crude birth and death rates of 29/1000 and 9/1000, respectively, compared to 12/1000 and 10/1000 in developed countries. Life expectancy at birth is 63 in developing countries, 50 in East and Central Africa, and 74 in the industrialized countries. Nearly all regions have entered the demographic transition, but they are at very different stages. As demographic trends diverge, the gap in economic development between developed and developing countries is widening. According to the 1996 World Report on Human Development, only 21.7% of the world's gross national product originates in developing countries. The differences are enormous in the degree of satisfaction of basic socioeconomic and health needs. It has become clear that demographic pressure is a determining factor in environmental degradation. Climatic disturbances, water pollution, deforestation and desertification attest to overconsumption of resources and emission of enormous quantities of wastes. Policies to control demographic growth have become the pivot of processes for construction of healthy societies. All studies have shown that issues of population, resources, and the environment are organically linked. Tunisia, a progressive country, has been concerned since independence with economic growth and social advancement of the population, and

  15. Structural basis for regulation of rhizobial nodulation and symbiosis gene expression by the regulatory protein NolR.

    PubMed

    Lee, Soon Goo; Krishnan, Hari B; Jez, Joseph M

    2014-04-29

    The symbiosis between rhizobial microbes and host plants involves the coordinated expression of multiple genes, which leads to nodule formation and nitrogen fixation. As part of the transcriptional machinery for nodulation and symbiosis across a range of Rhizobium, NolR serves as a global regulatory protein. Here, we present the X-ray crystal structures of NolR in the unliganded form and complexed with two different 22-base pair (bp) double-stranded operator sequences (oligos AT and AA). Structural and biochemical analysis of NolR reveals protein-DNA interactions with an asymmetric operator site and defines a mechanism for conformational switching of a key residue (Gln56) to accommodate variation in target DNA sequences from diverse rhizobial genes for nodulation and symbiosis. This conformational switching alters the energetic contributions to DNA binding without changes in affinity for the target sequence. Two possible models for the role of NolR in the regulation of different nodulation and symbiosis genes are proposed. To our knowledge, these studies provide the first structural insight on the regulation of genes involved in the agriculturally and ecologically important symbiosis of microbes and plants that leads to nodule formation and nitrogen fixation.

  16. Nonredundant regulation of rice arbuscular mycorrhizal symbiosis by two members of the phosphate transporter1 gene family.

    PubMed

    Yang, Shu-Yi; Grønlund, Mette; Jakobsen, Iver; Grotemeyer, Marianne Suter; Rentsch, Doris; Miyao, Akio; Hirochika, Hirohiko; Kumar, Chellian Santhosh; Sundaresan, Venkatesan; Salamin, Nicolas; Catausan, Sheryl; Mattes, Nicolas; Heuer, Sigrid; Paszkowski, Uta

    2012-10-01

    Pi acquisition of crops via arbuscular mycorrhizal (AM) symbiosis is becoming increasingly important due to limited high-grade rock Pi reserves and a demand for environmentally sustainable agriculture. Here, we show that 70% of the overall Pi acquired by rice (Oryza sativa) is delivered via the symbiotic route. To better understand this pathway, we combined genetic, molecular, and physiological approaches to determine the specific functions of two symbiosis-specific members of the PHOSPHATE TRANSPORTER1 (PHT1) gene family from rice, ORYsa;PHT1;11 (PT11) and ORYsa;PHT1;13 (PT13). The PT11 lineage of proteins from mono- and dicotyledons is most closely related to homologs from the ancient moss, indicating an early evolutionary origin. By contrast, PT13 arose in the Poaceae, suggesting that grasses acquired a particular strategy for the acquisition of symbiotic Pi. Surprisingly, mutations in either PT11 or PT13 affected the development of the symbiosis, demonstrating that both genes are important for AM symbiosis. For symbiotic Pi uptake, however, only PT11 is necessary and sufficient. Consequently, our results demonstrate that mycorrhizal rice depends on the AM symbiosis to satisfy its Pi demands, which is mediated by a single functional Pi transporter, PT11.

  17. Lipid metabolic changes in an early divergent fungus govern the establishment of a mutualistic symbiosis with endobacteria

    PubMed Central

    Lastovetsky, Olga A.; Gaspar, Maria L.; Mondo, Stephen J.; LaButti, Kurt M.; Sandor, Laura; Grigoriev, Igor V.; Pawlowska, Teresa E.

    2016-01-01

    The recent accumulation of newly discovered fungal–bacterial mutualisms challenges the paradigm that fungi and bacteria are natural antagonists. To understand the mechanisms that govern the establishment and maintenance over evolutionary time of mutualisms between fungi and bacteria, we studied a symbiosis of the fungus Rhizopus microsporus (Mucoromycotina) and its Burkholderia endobacteria. We found that nonhost R. microsporus, as well as other mucoralean fungi, interact antagonistically with endobacteria derived from the host and are not invaded by them. Comparison of gene expression profiles of host and nonhost fungi during interaction with endobacteria revealed dramatic changes in expression of lipid metabolic genes in the host. Analysis of the host lipidome confirmed that symbiosis establishment was accompanied by specific changes in the fungal lipid profile. Diacylglycerol kinase (DGK) activity was important for these lipid metabolic changes, as its inhibition altered the fungal lipid profile and caused a shift in the host–bacterial interaction into an antagonism. We conclude that adjustments in host lipid metabolism during symbiosis establishment, mediated by DGKs, are required for the mutualistic outcome of the Rhizopus–Burkholderia symbiosis. In addition, the neutral and phospholipid profiles of R. microsporus provide important insights into lipid metabolism in an understudied group of oleaginous Mucoromycotina. Lastly, our study revealed that the DGKs involved in the symbiosis form a previously uncharacterized clade of DGK domain proteins. PMID:27956601

  18. First Description of Sulphur-Oxidizing Bacterial Symbiosis in a Cnidarian (Medusozoa) Living in Sulphidic Shallow-Water Environments

    PubMed Central

    Abouna, Sylvie; Gonzalez-Rizzo, Silvina; Grimonprez, Adrien; Gros, Olivier

    2015-01-01

    Background Since the discovery of thioautotrophic bacterial symbiosis in the giant tubeworm Riftia pachyptila, there has been great impetus to investigate such partnerships in other invertebrates. In this study, we present the occurrence of a sulphur-oxidizing symbiosis in a metazoan belonging to the phylum Cnidaria in which this event has never been described previously. Methodology/Principal Findings Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) observations and Energy-dispersive X-ray spectroscopy (EDXs) analysis, were employed to unveil the presence of prokaryotes population bearing elemental sulphur granules, growing on the body surface of the metazoan. Phylogenetic assessments were also undertaken to identify this invertebrate and microorganisms in thiotrophic symbiosis. Our results showed the occurrence of a thiotrophic symbiosis in a cnidarian identified as Cladonema sp. Conclusions/Significance This is the first report describing the occurrence of a sulphur-oxidizing symbiosis in a cnidarian. Furthermore, of the two adult morphologies, the polyp and medusa, this mutualistic association was found restricted to the polyp form of Cladonema sp. PMID:26011278

  19. First Description of Sulphur-Oxidizing Bacterial Symbiosis in a Cnidarian (Medusozoa) Living in Sulphidic Shallow-Water Environments.

    PubMed

    Abouna, Sylvie; Gonzalez-Rizzo, Silvina; Grimonprez, Adrien; Gros, Olivier

    2015-01-01

    Since the discovery of thioautotrophic bacterial symbiosis in the giant tubeworm Riftia pachyptila, there has been great impetus to investigate such partnerships in other invertebrates. In this study, we present the occurrence of a sulphur-oxidizing symbiosis in a metazoan belonging to the phylum Cnidaria in which this event has never been described previously. Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) observations and Energy-dispersive X-ray spectroscopy (EDXs) analysis, were employed to unveil the presence of prokaryotes population bearing elemental sulphur granules, growing on the body surface of the metazoan. Phylogenetic assessments were also undertaken to identify this invertebrate and microorganisms in thiotrophic symbiosis. Our results showed the occurrence of a thiotrophic symbiosis in a cnidarian identified as Cladonema sp. This is the first report describing the occurrence of a sulphur-oxidizing symbiosis in a cnidarian. Furthermore, of the two adult morphologies, the polyp and medusa, this mutualistic association was found restricted to the polyp form of Cladonema sp.

  20. Compartment-specific activation of PPARγ governs breast cancer tumor growth, via metabolic reprogramming and symbiosis.

    PubMed

    Avena, Paola; Anselmo, Wanda; Whitaker-Menezes, Diana; Wang, Chenguang; Pestell, Richard G; Lamb, Rebecca S; Hulit, James; Casaburi, Ivan; Andò, Sebastiano; Martinez-Outschoorn, Ubaldo E; Lisanti, Michael P; Sotgia, Federica

    2013-05-01

    The role of PPARγ in cancer therapy is controversial, with studies showing either pro-tumorigenic or antineoplastic effects. This debate is very clinically relevant, because PPARγ agonists are used as antidiabetic drugs. Here, we evaluated if the effects of PPARγ on tumorigenesis are determined by the cell type in which PPARγ is activated. Second, we examined if the metabolic changes induced by PPARγ, such as glycolysis and autophagy, play any role in the tumorigenic process. To this end, PPARγ was overexpressed in breast cancer cells or in stromal cells. PPARγ-overexpressing cells were examined with respect to (1) their tumorigenic potential, using xenograft models, and (2) regarding their metabolic features. In xenograft models, we show that when PPARγ is activated in cancer cells, tumor growth is inhibited by 40%. However, when PPARγ is activated in stromal cells, the growth of co-injected breast cancer cells is enhanced by 60%. Thus, the effect(s) of PPARγ on tumorigenesis are dependent on the cell compartment in which PPARγ is activated. Mechanistically, stromal cells with activated PPARγ display metabolic features of cancer-associated fibroblasts, with increased autophagy, glycolysis and senescence. Indeed, fibroblasts overexpressing PPARγ show increased expression of autophagic markers, increased numbers of acidic autophagic vacuoles, increased production of L-lactate, cell hypertrophy and mitochondrial dysfunction. In addition, PPARγ fibroblasts show increased expression of CDKs (p16/p21) and β-galactosidase, which are markers of cell cycle arrest and senescence. Finally, PPARγ induces the activation of the two major transcription factors that promote autophagy and glycolysis, i.e., HIF-1α and NFκB, in stromal cells. Thus, PPARγ activation in stromal cells results in the formation of a catabolic pro-inflammatory microenvironment that metabolically supports cancer growth. Interestingly, the tumor inhibition observed when PPARγ is

  1. Compartment-specific activation of PPARγ governs breast cancer tumor growth, via metabolic reprogramming and symbiosis

    PubMed Central

    Avena, Paola; Anselmo, Wanda; Whitaker-Menezes, Diana; Wang, Chenguang; Pestell, Richard G.; Lamb, Rebecca S.; Hulit, James; Casaburi, Ivan; Andò, Sebastiano; Martinez-Outschoorn, Ubaldo E.; Lisanti, Michael P.; Sotgia, Federica

    2013-01-01

    The role of PPARγ in cancer therapy is controversial, with studies showing either pro-tumorigenic or antineoplastic effects. This debate is very clinically relevant, because PPARγ agonists are used as antidiabetic drugs. Here, we evaluated if the effects of PPARγ on tumorigenesis are determined by the cell type in which PPARγ is activated. Second, we examined if the metabolic changes induced by PPARγ, such as glycolysis and autophagy, play any role in the tumorigenic process. To this end, PPARγ was overexpressed in breast cancer cells or in stromal cells. PPARγ-overexpressing cells were examined with respect to (1) their tumorigenic potential, using xenograft models, and (2) regarding their metabolic features. In xenograft models, we show that when PPARγ is activated in cancer cells, tumor growth is inhibited by 40%. However, when PPARγ is activated in stromal cells, the growth of co-injected breast cancer cells is enhanced by 60%. Thus, the effect(s) of PPARγ on tumorigenesis are dependent on the cell compartment in which PPARγ is activated. Mechanistically, stromal cells with activated PPARγ display metabolic features of cancer-associated fibroblasts, with increased autophagy, glycolysis and senescence. Indeed, fibroblasts overexpressing PPARγ show increased expression of autophagic markers, increased numbers of acidic autophagic vacuoles, increased production of L-lactate, cell hypertrophy and mitochondrial dysfunction. In addition, PPARγ fibroblasts show increased expression of CDKs (p16/p21) and β-galactosidase, which are markers of cell cycle arrest and senescence. Finally, PPARγ induces the activation of the two major transcription factors that promote autophagy and glycolysis, i.e., HIF-1α and NFκB, in stromal cells. Thus, PPARγ activation in stromal cells results in the formation of a catabolic pro-inflammatory microenvironment that metabolically supports cancer growth. Interestingly, the tumor inhibition observed when PPARγ is

  2. The molecular basis of bacterial-insect symbiosis

    PubMed Central

    Douglas, Angela E.

    2015-01-01

    Insects provide experimentally tractable and cost-effective model systems to investigate the molecular basis of animal-bacterial interactions. Recent research is revealing the central role of the insect innate immune system, especially anti-microbial peptides and reactive oxygen species, in regulating the abundance and composition of the microbiota in various insects, including Drosophila and the mosquitoes Aedes and Anopheles. Interactions between the immune system and microbiota are, however, bidirectional with evidence that members of the resident microbiota can promote immune function, conferring resistance to pathogens and parasites by both activation of immune effectors and production of toxins. Antagonistic and mutualistic interactions among bacteria have also been implicated as determinants of the microbiota composition, including exclusion of pathogens, but the molecular mechanisms are largely unknown. Some bacteria are crucial for insect nutrition, through provisioning of specific nutrients (e.g. B vitamins, essential amino acids) and modulation of the insect nutritional sensing and signaling pathways (e.g. insulin signaling) that regulate nutrient allocation, especially to lipid and other energy reserves. A key challenge for future research is to identify the molecular interaction between specific bacterial effectors and animal receptors, and to determine how these interactions translate into microbiota-dependent signaling, metabolism and immune function in the host. PMID:24735869

  3. The molecular basis of bacterial-insect symbiosis.

    PubMed

    Douglas, Angela E

    2014-11-25

    Insects provide experimentally tractable and cost-effective model systems to investigate the molecular basis of animal-bacterial interactions. Recent research is revealing the central role of the insect innate immune system, especially anti-microbial peptides and reactive oxygen species, in regulating the abundance and composition of the microbiota in various insects, including Drosophila and the mosquitoes Aedes and Anopheles. Interactions between the immune system and microbiota are, however, bidirectional with evidence that members of the resident microbiota can promote immune function, conferring resistance to pathogens and parasites by both activation of immune effectors and production of toxins. Antagonistic and mutualistic interactions among bacteria have also been implicated as determinants of the microbiota composition, including exclusion of pathogens, but the molecular mechanisms are largely unknown. Some bacteria are crucial for insect nutrition, through provisioning of specific nutrients (e.g., B vitamins, essential amino acids) and modulation of the insect nutritional sensing and signaling pathways (e.g., insulin signaling) that regulate nutrient allocation, especially to lipid and other energy reserves. A key challenge for future research is to identify the molecular interaction between specific bacterial effectors and animal receptors, as well as to determine how these interactions translate into microbiota-dependent signaling, metabolism, and immune function in the host.

  4. Functional analysis of duplicated Symbiosis Receptor Kinase (SymRK) genes during nodulation and mycorrhizal infection in soybean (Glycine max).

    PubMed

    Indrasumunar, Arief; Wilde, Julia; Hayashi, Satomi; Li, Dongxue; Gresshoff, Peter M

    2015-03-15

    Association between legumes and rhizobia results in the formation of root nodules, where symbiotic nitrogen fixation occurs. The early stages of this association involve a complex of signalling events between the host and microsymbiont. Several genes dealing with early signal transduction have been cloned, and one of them encodes the leucine-rich repeat (LRR) receptor kinase (SymRK; also termed NORK). The Symbiosis Receptor Kinase gene is required by legumes to establish a root endosymbiosis with Rhizobium bacteria as well as mycorrhizal fungi. Using degenerate primer and BAC sequencing, we cloned duplicated SymRK homeologues in soybean called GmSymRKα and GmSymRKβ. These duplicated genes have high similarity of nucleotide (96%) and amino acid sequence (95%). Sequence analysis predicted a malectin-like domain within the extracellular domain of both genes. Several putative cis-acting elements were found in promoter regions of GmSymRKα and GmSymRKβ, suggesting a participation in lateral root development, cell division and peribacteroid membrane formation. The mutant of SymRK genes is not available in soybean; therefore, to know the functions of these genes, RNA interference (RNAi) of these duplicated genes was performed. For this purpose, RNAi construct of each gene was generated and introduced into the soybean genome by Agrobacterium rhizogenes-mediated hairy root transformation. RNAi of GmSymRKβ gene resulted in an increased reduction of nodulation and mycorrhizal infection than RNAi of GmSymRKα, suggesting it has the major activity of the duplicated gene pair. The results from the important crop legume soybean confirm the joint phenotypic action of GmSymRK genes in both mycorrhizal and rhizobial infection seen in model legumes.

  5. Structure-function analysis of nod factor-induced root hair calcium spiking in Rhizobium-legume symbiosis.

    PubMed

    Wais, Rebecca J; Keating, David H; Long, Sharon R

    2002-05-01

    In the Rhizobium-legume symbiosis, compatible bacteria and host plants interact through an exchange of signals: Host compounds promote the expression of bacterial biosynthetic nod (nodulation) genes leading to the production of a lipochito-oligosaccharide signal, the Nod factor (NF). The particular array of nod genes carried by a given species of Rhizobium determines the NF structure synthesized and defines the range of legume hosts by which the bacterium is recognized. Purified NF can induce early host responses even in the absence of live Rhizobium One of the earliest known host responses to NF is an oscillatory behavior of cytoplasmic calcium, or calcium spiking, in root hair cells, initially observed in Medicago spp. and subsequently characterized in four other genera (D.W. Ehrhardt, R. Wais, S.R. Long [1996] Cell 85: 673-681; S.A. Walker, V. Viprey, J.A. Downie [2000] Proc Natl Acad Sci USA 97: 13413-13418; D.W. Ehrhardt, J.A. Downie, J. Harris, R.J. Wais, and S.R. Long, unpublished data). We sought to determine whether live Rhizobium trigger a rapid calcium spiking response and whether this response is NF dependent. We show that, in the Sinorhizobium meliloti-Medicago truncatula interaction, bacteria elicit a calcium spiking response that is indistinguishable from the response to purified NF. We determine that calcium spiking is a nod gene-dependent host response. Studies of calcium spiking in M. truncatula and alfalfa (Medicago sativa) also uncovered the possibility of differences in early NF signal transduction. We further demonstrate the sufficiency of the nod genes for inducing calcium spiking by using Escherichia coli BL21 (DE3) engineered to express 11 S. meliloti nod genes.

  6. Structure-Function Analysis of Nod Factor-Induced Root Hair Calcium Spiking in Rhizobium-Legume Symbiosis1

    PubMed Central

    Wais, Rebecca J.; Keating, David H.; Long, Sharon R.

    2002-01-01

    In the Rhizobium-legume symbiosis, compatible bacteria and host plants interact through an exchange of signals: Host compounds promote the expression of bacterial biosynthetic nod (nodulation) genes leading to the production of a lipochito-oligosaccharide signal, the Nod factor (NF). The particular array of nod genes carried by a given species of Rhizobium determines the NF structure synthesized and defines the range of legume hosts by which the bacterium is recognized. Purified NF can induce early host responses even in the absence of live Rhizobium One of the earliest known host responses to NF is an oscillatory behavior of cytoplasmic calcium, or calcium spiking, in root hair cells, initially observed in Medicago spp. and subsequently characterized in four other genera (D.W. Ehrhardt, R. Wais, S.R. Long [1996] Cell 85: 673–681; S.A. Walker, V. Viprey, J.A. Downie [2000] Proc Natl Acad Sci USA 97: 13413–13418; D.W. Ehrhardt, J.A. Downie, J. Harris, R.J. Wais, and S.R. Long, unpublished data). We sought to determine whether live Rhizobium trigger a rapid calcium spiking response and whether this response is NF dependent. We show that, in the Sinorhizobium meliloti-Medicago truncatula interaction, bacteria elicit a calcium spiking response that is indistinguishable from the response to purified NF. We determine that calcium spiking is a nod gene-dependent host response. Studies of calcium spiking in M. truncatula and alfalfa (Medicago sativa) also uncovered the possibility of differences in early NF signal transduction. We further demonstrate the sufficiency of the nod genes for inducing calcium spiking by using Escherichia coli BL21 (DE3) engineered to express 11 S. meliloti nod genes. PMID:12011352

  7. Oncogenes induce the cancer-associated fibroblast phenotype: metabolic symbiosis and "fibroblast addiction" are new therapeutic targets for drug discovery.

    PubMed

    Lisanti, Michael P; Martinez-Outschoorn, Ubaldo E; Sotgia, Federica

    2013-09-01

    Metabolic coupling, between mitochondria in cancer cells and catabolism in stromal fibroblasts, promotes tumor growth, recurrence, metastasis, and predicts anticancer drug resistance. Catabolic fibroblasts donate the necessary fuels (such as L-lactate, ketones, glutamine, other amino acids, and fatty acids) to anabolic cancer cells, to metabolize via their TCA cycle and oxidative phosphorylation (OXPHOS). This provides a simple mechanism by which metabolic energy and biomass are transferred from the host microenvironment to cancer cells. Recently, we showed that catabolic metabolism and "glycolytic reprogramming" in the tumor microenvironment are orchestrated by oncogene activation and inflammation, which originates in epithelial cancer cells. Oncogenes drive the onset of the cancer-associated fibroblast phenotype in adjacent normal fibroblasts via paracrine oxidative stress. This oncogene-induced transition to malignancy is "mirrored" by a loss of caveolin-1 (Cav-1) and an increase in MCT4 in adjacent stromal fibroblasts, functionally reflecting catabolic metabolism in the tumor microenvironment. Virtually identical findings were obtained using BRCA1-deficient breast and ovarian cancer cells. Thus, oncogene activation (RAS, NFkB, TGF-β) and/or tumor suppressor loss (BRCA1) have similar functional effects on adjacent stromal fibroblasts, initiating "metabolic symbiosis" and the cancer-associated fibroblast phenotype. New therapeutic strategies that metabolically uncouple oxidative cancer cells from their glycolytic stroma or modulate oxidative stress could be used to target this lethal subtype of cancers. Targeting "fibroblast addiction" in primary and metastatic tumor cells may expose a critical Achilles' heel, leading to disease regression in both sporadic and familial cancers.

  8. Industrial diamond

    USGS Publications Warehouse

    Olson, D.W.

    2001-01-01

    An overview of the industrial diamond industry is provided. More than 90 percent of the industrial diamond consumed in the U.S. and the rest of the world is manufactured diamond. Ireland, Japan, Russia, and the U.S. produce 75 percent of the global industrial diamond output. In 2000, the U.S. was the largest market for industrial diamond. Industrial diamond applications, prices for industrial diamonds, imports and exports of industrial diamonds, the National Defense Stockpile of industrial diamonds, and the outlook for the industrial diamond market are discussed.

  9. Polyester synthesis genes associated with stress resistance are involved in an insect-bacterium symbiosis.

    PubMed

    Kim, Jiyeun Kate; Won, Yeo Jin; Nikoh, Naruo; Nakayama, Hiroshi; Han, Sang Heum; Kikuchi, Yoshitomo; Rhee, Young Ha; Park, Ha Young; Kwon, Jeong Yun; Kurokawa, Kenji; Dohmae, Naoshi; Fukatsu, Takema; Lee, Bok Luel

    2013-06-25

    Many bacteria accumulate granules of polyhydroxyalkanoate (PHA) within their cells, which confer resistance to nutritional depletion and other environmental stresses. Here, we report an unexpected involvement of the bacterial endocellular storage polymer, PHA, in an insect-bacterium symbiotic association. The bean bug Riptortus pedestris harbors a beneficial and specific gut symbiont of the β-proteobacterial genus Burkholderia, which is orally acquired by host nymphs from the environment every generation and easily cultivable and genetically manipulatable. Biochemical and cytological comparisons between symbiotic and cultured Burkholderia detected more PHA granules consisting of poly-3-hydroxybutyrate and associated phasin (PhaP) protein in the symbiotic Burkholderia. Among major PHA synthesis genes, phaB and phaC were disrupted by homologous recombination together with the phaP gene, whereby ΔphaB, ΔphaC, and ΔphaP mutants were generated. Both in culture and in symbiosis, accumulation of PHA granules was strongly suppressed in ΔphaB and ΔphaC, but only moderately in ΔphaP. In symbiosis, the host insects infected with ΔphaB and ΔphaC exhibited significantly lower symbiont densities and smaller body sizes. These deficient phenotypes associated with ΔphaB and ΔphaC were restored by complementation of the mutants with plasmids encoding a functional phaB/phaC gene. Retention analysis of the plasmids revealed positive selection acting on the functional phaB/phaC in symbiosis. These results indicate that the PHA synthesis genes of the Burkholderia symbiont are required for normal symbiotic association with the Riptortus host. In vitro culturing analyses confirmed vulnerability of the PHA gene mutants to environmental stresses, suggesting that PHA may play a role in resisting stress under symbiotic conditions.

  10. Metabolic Coevolution in the Bacterial Symbiosis of Whiteflies and Related Plant Sap-Feeding Insects.

    PubMed

    Luan, Jun-Bo; Chen, Wenbo; Hasegawa, Daniel K; Simmons, Alvin M; Wintermantel, William M; Ling, Kai-Shu; Fei, Zhangjun; Liu, Shu-Sheng; Douglas, Angela E

    2015-09-15

    Genomic decay is a common feature of intracellular bacteria that have entered into symbiosis with plant sap-feeding insects. This study of the whitefly Bemisia tabaci and two bacteria (Portiera aleyrodidarum and Hamiltonella defensa) cohoused in each host cell investigated whether the decay of Portiera metabolism genes is complemented by host and Hamiltonella genes, and compared the metabolic traits of the whitefly symbiosis with other sap-feeding insects (aphids, psyllids, and mealybugs). Parallel genomic and transcriptomic analysis revealed that the host genome contributes multiple metabolic reactions that complement or duplicate Portiera function, and that Hamiltonella may contribute multiple cofactors and one essential amino acid, lysine. Homologs of the Bemisia metabolism genes of insect origin have also been implicated in essential amino acid synthesis in other sap-feeding insect hosts, indicative of parallel coevolution of shared metabolic pathways across multiple symbioses. Further metabolism genes coded in the Bemisia genome are of bacterial origin, but phylogenetically distinct from Portiera, Hamiltonella and horizontally transferred genes identified in other sap-feeding insects. Overall, 75% of the metabolism genes of bacterial origin are functionally unique to one symbiosis, indicating that the evolutionary history of metabolic integration in these symbioses is strongly contingent on the pattern of horizontally acquired genes. Our analysis, further, shows that bacteria with genomic decay enable host acquisition of complex metabolic pathways by multiple independent horizontal gene transfers from exogenous bacteria. Specifically, each horizontally acquired gene can function with other genes in the pathway coded by the symbiont, while facilitating the decay of the symbiont gene coding the same reaction.

  11. Host plant peptides elicit a transcriptional response to control the Sinorhizobium meliloti cell cycle during symbiosis.

    PubMed

    Penterman, Jon; Abo, Ryan P; De Nisco, Nicole J; Arnold, Markus F F; Longhi, Renato; Zanda, Matteo; Walker, Graham C

    2014-03-04

    The α-proteobacterium Sinorhizobium meliloti establishes a chronic intracellular infection during the symbiosis with its legume hosts. Within specialized host cells, S. meliloti differentiates into highly polyploid, enlarged nitrogen-fixing bacteroids. This differentiation is driven by host cells through the production of defensin-like peptides called "nodule-specific cysteine-rich" (NCR) peptides. Recent research has shown that synthesized NCR peptides exhibit antimicrobial activity at high concentrations but cause bacterial endoreduplication at sublethal concentrations. We leveraged synchronized S. meliloti populations to determine how treatment with a sublethal NCR peptide affects the cell cycle and physiology of bacteria at the molecular level. We found that at sublethal levels a representative NCR peptide specifically blocks cell division and antagonizes Z-ring function. Gene-expression profiling revealed that the cell division block was produced, in part, through the substantial transcriptional response elicited by sublethal NCR treatment that affected ∼15% of the genome. Expression of critical cell-cycle regulators, including ctrA, and cell division genes, including genes required for Z-ring function, were greatly attenuated in NCR-treated cells. In addition, our experiments identified important symbiosis functions and stress responses that are induced by sublethal levels of NCR peptides and other antimicrobial peptides. Several of these stress-response pathways also are found in related α-proteobacterial pathogens and might be used by S. meliloti to sense host cues during infection. Our data suggest a model in which, in addition to provoking stress responses, NCR peptides target intracellular regulatory pathways to drive S. meliloti endoreduplication and differentiation during symbiosis.

  12. Metabolic Complementarity and Genomics of the Dual Bacterial Symbiosis of Sharpshooters

    PubMed Central

    Wu, Dongying; Daugherty, Sean C; Van Aken, Susan E; Pai, Grace H; Watkins, Kisha L; Khouri, Hoda; Tallon, Luke J; Zaborsky, Jennifer M; Dunbar, Helen E; Tran, Phat L; Moran, Nancy A

    2006-01-01

    Mutualistic intracellular symbiosis between bacteria and insects is a widespread phenomenon that has contributed to the global success of insects. The symbionts, by provisioning nutrients lacking from diets, allow various insects to occupy or dominate ecological niches that might otherwise be unavailable. One such insect is the glassy-winged sharpshooter (Homalodisca coagulata), which feeds on xylem fluid, a diet exceptionally poor in organic nutrients. Phylogenetic studies based on rRNA have shown two types of bacterial symbionts to be coevolving with sharpshooters: the gamma-proteobacterium Baumannia cicadellinicola and the Bacteroidetes species Sulcia muelleri. We report here the sequencing and analysis of the 686,192–base pair genome of B. cicadellinicola and approximately 150 kilobase pairs of the small genome of S. muelleri, both isolated from H. coagulata. Our study, which to our knowledge is the first genomic analysis of an obligate symbiosis involving multiple partners, suggests striking complementarity in the biosynthetic capabilities of the two symbionts: B. cicadellinicola devotes a substantial portion of its genome to the biosynthesis of vitamins and cofactors required by animals and lacks most amino acid biosynthetic pathways, whereas S. muelleri apparently produces most or all of the essential amino acids needed by its host. This finding, along with other results of our genome analysis, suggests the existence of metabolic codependency among the two unrelated endosymbionts and their insect host. This dual symbiosis provides a model case for studying correlated genome evolution and genome reduction involving multiple organisms in an intimate, obligate mutualistic relationship. In addition, our analysis provides insight for the first time into the differences in symbionts between insects (e.g., aphids) that feed on phloem versus those like H. coagulata that feed on xylem. Finally, the genomes of these two symbionts provide potential targets for

  13. Symbiosis induces widespread changes in the proteome of the model cnidarian Aiptasia.

    PubMed

    Oakley, Clinton A; Ameismeier, Michael F; Peng, Lifeng; Weis, Virginia M; Grossman, Arthur R; Davy, Simon K

    2016-07-01

    Coral reef ecosystems are metabolically founded on the mutualism between corals and photosynthetic dinoflagellates of the genus Symbiodinium. The glass anemone Aiptasia sp. has become a tractable model for this symbiosis, and recent advances in genetic information have enabled the use of mass spectrometry-based proteomics in this model. We utilized label-free liquid chromatography electrospray-ionization tandem mass spectrometry to analyze the effects of symbiosis on the proteomes of symbiotic and aposymbiotic Aiptasia. We identified and obtained relative quantification of more than 3,300 proteins in 1,578 protein clusters, with 81 protein clusters showing significantly different expression between symbiotic states. Symbiotic anemones showed significantly higher expression of proteins involved in lipid storage and transport, nitrogen transport and cycling, intracellular trafficking, endocytosis and inorganic carbon transport. These changes reflect shifts in host metabolism and nutrient reserves due to increased nutritional exchange with the symbionts, as well as mechanisms for supplying inorganic nutrients to the algae. Aposymbiotic anemones exhibited increased expression of multiple systems responsible for mediating reactive oxygen stress, suggesting that the host derives direct or indirect protection from oxidative stress while in symbiosis. Aposymbiotic anemones also increased their expression of an array of proteases and chitinases, indicating a metabolic shift from autotrophy to heterotrophy. These results provide a comprehensive Aiptasia proteome with more direct relative quantification of protein abundance than transcriptomic methods. The extension of "omics" techniques to this model system will allow more powerful studies of coral physiology, ecosystem function, and the effects of biotic and abiotic stress on the coral-dinoflagellate mutualism.

  14. Use of carbon monoxide and hydrogen by a bacteria-animal symbiosis from seagrass sediments

    SciTech Connect

    Kleiner, Manuel; Wentrup, Cecilia; Holler, Thomas; Lavik, Gaute; Harder, Jens; Lott, Christian; Littmann, Sten; Kuypers, Marcel M. M.; Dubilier, Nicole

    2015-05-27

    The gutless marine worm Olavius algarvensis lives in symbiosis with chemosynthetic bacteria that provide nutrition by fixing carbon dioxide (CO2) into biomass using reduced sulfur compounds as energy sources. A recent metaproteomic analysis of the O. algarvensis symbiosis indicated that carbon monoxide (CO) and hydrogen (H2) might also be used as energy sources. We provide direct evidence that the O. algarvensis symbiosis consumes CO and H2. Single cell imaging using nanoscale secondary ion mass spectrometry revealed that one of the symbionts, the γ3-symbiont, uses the energy from CO oxidation to fix CO2. Pore water analysis revealed considerable in-situ concentrations of CO and H2 in the O. algarvensis environment, Mediterranean seagrass sediments. Pore water H2 concentrations (89-2147 nM) were up to two orders of magnitude higher than in seawater, and up to 36-fold higher than previously known from shallow-water marine sediments. Pore water CO concentrations (17-51 nM) were twice as high as in the overlying seawater (no literature data from other shallow-water sediments are available for comparison). Ex-situ incubation experiments showed that dead seagrass rhizomes produced large amounts of CO. Lastly, CO production from decaying plant material could thus be a significant energy source for microbial primary production in seagrass sediments.

  15. Polyester synthesis genes associated with stress resistance are involved in an insect–bacterium symbiosis

    PubMed Central

    Kim, Jiyeun Kate; Won, Yeo Jin; Nikoh, Naruo; Nakayama, Hiroshi; Han, Sang Heum; Kikuchi, Yoshitomo; Rhee, Young Ha; Park, Ha Young; Kwon, Jeong Yun; Kurokawa, Kenji; Dohmae, Naoshi; Fukatsu, Takema; Lee, Bok Luel

    2013-01-01

    Many bacteria accumulate granules of polyhydroxyalkanoate (PHA) within their cells, which confer resistance to nutritional depletion and other environmental stresses. Here, we report an unexpected involvement of the bacterial endocellular storage polymer, PHA, in an insect–bacterium symbiotic association. The bean bug Riptortus pedestris harbors a beneficial and specific gut symbiont of the β-proteobacterial genus Burkholderia, which is orally acquired by host nymphs from the environment every generation and easily cultivable and genetically manipulatable. Biochemical and cytological comparisons between symbiotic and cultured Burkholderia detected more PHA granules consisting of poly-3-hydroxybutyrate and associated phasin (PhaP) protein in the symbiotic Burkholderia. Among major PHA synthesis genes, phaB and phaC were disrupted by homologous recombination together with the phaP gene, whereby ΔphaB, ΔphaC, and ΔphaP mutants were generated. Both in culture and in symbiosis, accumulation of PHA granules was strongly suppressed in ΔphaB and ΔphaC, but only moderately in ΔphaP. In symbiosis, the host insects infected with ΔphaB and ΔphaC exhibited significantly lower symbiont densities and smaller body sizes. These deficient phenotypes associated with ΔphaB and ΔphaC were restored by complementation of the mutants with plasmids encoding a functional phaB/phaC gene. Retention analysis of the plasmids revealed positive selection acting on the functional phaB/phaC in symbiosis. These results indicate that the PHA synthesis genes of the Burkholderia symbiont are required for normal symbiotic association with the Riptortus host. In vitro culturing analyses confirmed vulnerability of the PHA gene mutants to environmental stresses, suggesting that PHA may play a role in resisting stress under symbiotic conditions. PMID:23757494

  16. A Transcriptional Program for Arbuscule Degeneration during AM Symbiosis Is Regulated by MYB1.

    PubMed

    Floss, Daniela S; Gomez, S Karen; Park, Hee-Jin; MacLean, Allyson M; Müller, Lena M; Bhattarai, Kishor K; Lévesque-Tremblay, Veronique; Maldonado-Mendoza, Ignacio E; Harrison, Maria J

    2017-04-24

    During the endosymbiosis formed between plants and arbuscular mycorrhizal (AM) fungi, the root cortical cells are colonized by branched hyphae called arbuscules, which function in nutrient exchange with the plant [1]. Despite their positive function, arbuscules are ephemeral structures, and their development is followed by a degeneration phase, in which the arbuscule and surrounding periarbuscular membrane and matrix gradually disappear from the root cell [2, 3]. Currently, the root cell's role in this process and the underlying regulatory mechanisms are unknown. Here, by using a Medicago truncatula pt4 mutant in which arbuscules degenerate prematurely [4], we identified arbuscule degeneration-associated genes, of which 38% are predicted to encode secreted hydrolases, suggesting a role in disassembly of the arbuscule and interface. Through RNAi and analysis of an insertion mutant, we identified a symbiosis-specific MYB-like transcription factor (MYB1) that suppresses arbuscule degeneration in mtpt4. In myb1, expression of several degeneration-associated genes is reduced. Conversely, in roots constitutively overexpressing MYB1, expression of degeneration-associated genes is increased and subsequent development of symbiosis is impaired. MYB1-regulated gene expression is enhanced by DELLA proteins and is dependent on NSP1 [5], but not NSP2 [6]. Furthermore, MYB1 interacts with DELLA and NSP1. Our data identify a transcriptional program for arbuscule degeneration and reveal that its regulators include MYB1 in association with two transcriptional regulators, NSP1 and DELLA, both of which function in preceding phases of the symbiosis. We propose that the combinatorial use of transcription factors enables the sequential expression of transcriptional programs for arbuscule development and degeneration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Selenium hyperaccumulation by Astragalus (Fabaceae) does not inhibit root nodule symbiosis.

    PubMed

    Alford, Elan R; Pilon-Smits, Elizabeth A H; Fakra, Sirine C; Paschke, Mark W

    2012-12-01

    A survey of the root-nodule symbiosis in Astragalus and its interaction with selenium (Se) has not been conducted before. Such studies can provide insight into how edaphic conditions modify symbiotic interactions and influence partner coevolution. In this paper plant-organ Se concentration ([Se]) was investigated to assess potential Se exposure to endophytes. • Selenium distribution and molecular speciation of root nodules from Se-hyperaccumulators Astragalus bisulcatus, A. praelongus, and A. racemosus was determined by Se K-edge x-ray absorption spectroscopy. A series of greenhouse experiments were conducted to characterize the response of root-nodule symbiosis in Se-hyperaccumulators and nonhyperaccumulators. • Nodules in three Se-hyperaccumulators (Astragalus crotalariae, A. praelongus, and A. preussii) are reported for the first time. Leaves, flowers, and fruits from Se-hyperaccumulators were routinely above the hyperaccumulator threshold (1,000 µg Se g(-1) DW), but root samples rarely contained that amount, and nodules never exceeded 110 µg Se g(-1) DW. Nodules from A. bisulcatus, A. praelongus, and A. racemosus had Se throughout, with a majority stored in C-Se-C form. Finally, an evaluation of nodulation in Se-hyperaccumulators and nonhyperaccumulators indicated that there was no nodulation inhibition because of plant Se tolerance. Rather, we found that in Se-hyperaccumulators higher levels of Se treatment (up to 100 µM Se) corresponded with higher nodule counts, indicating a potential role for dinitrogen fixation in Se-hyperaccumulation. The effect was not found in nonhyperaccumulators. • As the evolution of Se hyperaccumulation in Astragalus developed, root-nodule symbiosis may have played an integral role.

  18. The plasma membrane proteome of Medicago truncatula roots as modified by arbuscular mycorrhizal symbiosis.

    PubMed

    Aloui, Achref; Recorbet, Ghislaine; Lemaître-Guillier, Christelle; Mounier, Arnaud; Balliau, Thierry; Zivy, Michel; Wipf, Daniel; Dumas-Gaudot, Eliane

    2017-07-19

    In arbuscular mycorrhizal (AM) roots, the plasma membrane (PM) of the host plant is involved in all developmental stages of the symbiotic interaction, from initial recognition to intracellular accommodation of intra-radical hyphae and arbuscules. Although the role of the PM as the agent for cellular morphogenesis and nutrient exchange is especially accentuated in endosymbiosis, very little is known regarding the PM protein composition of mycorrhizal roots. To obtain a global overview at the proteome level of the host PM proteins as modified by symbiosis, we performed a comparative protein profiling of PM fractions from Medicago truncatula roots either inoculated or not with the AM fungus Rhizophagus irregularis. PM proteins were isolated from root microsomes using an optimized discontinuous sucrose gradient; their subsequent analysis by liquid chromatography followed by mass spectrometry (MS) identified 674 proteins. Cross-species sequence homology searches combined with MS-based quantification clearly confirmed enrichment in PM-associated proteins and depletion of major microsomal contaminants. Changes in protein amounts between the PM proteomes of mycorrhizal and non-mycorrhizal roots were monitored further by spectral counting. This workflow identified a set of 82 mycorrhiza-responsive proteins that provided insights into the plant PM response to mycorrhizal symbiosis. Among them, the association of one third of the mycorrhiza-responsive proteins with detergent-resistant membranes pointed at partitioning to PM microdomains. The PM-associated proteins responsive to mycorrhization also supported host plant control of sugar uptake to limit fungal colonization, and lipid turnover events in the PM fraction of symbiotic roots. Because of the depletion upon symbiosis of proteins mediating the replacement of phospholipids by phosphorus-free lipids in the plasmalemma, we propose a role of phosphate nutrition in the PM composition of mycorrhizal roots.

  19. Genomic analysis reveals key aspects of prokaryotic symbiosis in the phototrophic consortium “Chlorochromatium aggregatum”

    PubMed Central

    2013-01-01

    Background ‘Chlorochromatium aggregatum’ is a phototrophic consortium, a symbiosis that may represent the highest degree of mutual interdependence between two unrelated bacteria not associated with a eukaryotic host. ‘Chlorochromatium aggregatum’ is a motile, barrel-shaped aggregate formed from a single cell of ‘Candidatus Symbiobacter mobilis”, a polarly flagellated, non-pigmented, heterotrophic bacterium, which is surrounded by approximately 15 epibiont cells of Chlorobium chlorochromatii, a non-motile photolithoautotrophic green sulfur bacterium. Results We analyzed the complete genome sequences of both organisms to understand the basis for this symbiosis. Chl. chlorochromatii has acquired relatively few symbiosis-specific genes; most acquired genes are predicted to modify the cell wall or function in cell-cell adhesion. In striking contrast, ‘Ca. S. mobilis’ appears to have undergone massive gene loss, is probably no longer capable of independent growth, and thus may only reproduce when consortia divide. A detailed model for the energetic and metabolic bases of the dependency of ‘Ca. S. mobilis’ on Chl. chlorochromatii is described. Conclusions Genomic analyses suggest that three types of interactions lead to a highly sophisticated relationship between these two organisms. Firstly, extensive metabolic exchange, involving carbon, nitrogen, and sulfur sources as well as vitamins, occurs from the epibiont to the central bacterium. Secondly, ‘Ca. S. mobilis’ can sense and move towards light and sulfide, resources that only directly benefit the epibiont. Thirdly, electron cycling mechanisms, particularly those mediated by quinones and potentially involving shared protonmotive force, could provide an important basis for energy exchange in this and other symbiotic relationships. PMID:24267588

  20. Context Dependency of a Marine Defensive Symbiosis over a Wide Geographic Distribution

    NASA Astrophysics Data System (ADS)

    Lopanik, N.; Linneman, J.; Mathew, M.

    2016-02-01

    The invasive, temperate marine bryozoan Bugula neritina possesses an uncultured, vertically-transmitted bacterial symbiont that produces natural products known as bryostatins. These unpalatable polyketides protect the host larvae from predation. In the western Atlantic, two host genotypes were thought to be restricted to differing latitudes based on the presence of the defensive symbiont: undefended aposymbiotic Type N animals were found at high latitudes, while defended symbiotic Type S colonies were found at low latitudes, where predation pressure is higher. We found that the host genotypes are more widespread than previously thought, but that the symbiont appeared to be restricted to hosts at lower latitudes, regardless of host phylotype, leading to the question of what factors are involved in restricting the symbiont's range. We performed reciprocal transplant experiments of symbiotic and antibiotic-cured hosts, and measured host growth, a proxy for fitness. Our data indicate that possession of the symbiont appears to present a physiological cost to the host. This cost may be more pronounced at higher latitudes where the benefit of symbiosis is less apparent. In addition, preliminary evidence suggests that symbiont titer in a Type S colony from North Carolina transplanted to Virginia is reduced over a period of nearly 4 months. Taken together, these results suggest that a combination of factors may play a role in the distribution of the defensive symbiont: (i) hosts that possess the symbiont are outcompeted by aposymbiotic conspecifics at high latitude and reduced levels of predation pressure; and (ii) symbiont growth may be inhibited or sanctioned by the host at high latitudes. As defensive symbiosis is an important trait in marine habitats, understanding factors that affect the distribution of both the host and symbiont are necessary to fully appreciate the ecological impact of symbiosis.

  1. Gibberellins and the Legume-Rhizobium Symbiosis 1

    PubMed Central

    Dobert, Raymond C.; Rood, Stewart B.; Zanewich, Karen; Blevins, Dale G.

    1992-01-01

    Lima bean (Phaseolus lunatus L.) plants inoculated with Bradyrhizobium sp. strain 127E14 displayed a period of marked internode elongation that was not observed in plants inoculated with other compatible bradyrhizobia, including strain 127E15. When strain 127E14 nodulated an alternate host, cowpea (Vigna unguiculata L. Walp), a similar, although less dramatic growth response induced by the bacteria was observed. It has been speculated that the elongative growth promotion brought about by inoculation with strain 127E14 is mediated by gibberellins (GAs). Using deuterated internal standards and gas chromatography-mass spectroscopy analysis, we have quantified the levels of GA1, GA20, GA19, and GA44 in nodules and stems of two varieties of lima bean (bush and pole) and one variety of cowpea that were inoculated with either strain 127E14 or 127E15. In nodules formed by strain 127E14 on lima bean, endogenous levels of GA20 and GA19 were 10 to 40 times higher (35-88 ng/g dry weight) than amounts found in nodules formed by strain 127E15 (2.2-3.9 ng/g dry weight). Relative amounts of GA44 were also higher (4- to 11-fold) in 127E14 nodules, but this increase was less pronounced. The rhizobial-induced increase of these GAs in the nodule occurred in both pole and bush varieties and seemed to be independent of host morphology. Regardless of rhizobial inoculum, levels of the “bioactive” GA1 in the nodule (0.3-1.1 ng/g dry weight) were similar. In cowpea nodules, a similar, although smaller, difference in GA content due to rhizobial strain was observed. The concentration of GA1 in lima bean stems was generally higher than that observed in the nodule, whereas concentrations of the other GAs measured were lower. In contrast with the nodule, GA concentrations in lima bean stems were not greater in plants inoculated with strain 127E14, and in some cases the slower growing plants inoculated with strain 127E15 actually had higher levels of GA20, GA19, and GA44. Thus, there were

  2. Is the evolution of the coral-algal symbiosis linked to fluctuations in seawater magnesium concentrations?

    NASA Astrophysics Data System (ADS)

    Giri, S.; Devlin, Q.; Swart, P. K.

    2014-12-01

    While Scleractinia first appear in shallow tropical seas during the Mid-Triassic, it is unclear when and why these corals established their symbiosis with a dinoflagellate alga (Symbiodinium microadriaticum). The development of this symbiosis was a major evolutionary innovation for corals, which was not previously observed in other coral taxa (Rugosa and Tabulata) and likely contributed to the rise of Scleractinia as the dominant reef builders. Inarguably, this symbiotic relationship is linked to increased calcification rates but dinoflagellate symbioses are also very common in non-calcifying marine invertebrates making it unclear whether the coral host or algal symbiont drives the establishment of this symbiosis. Recently, it has been suggested that the establishment of the coral-algal symbiosis is symbiont driven by the fluctuation of the Mg/Ca ratio of seawater at the beginning of the Mesozoic. Scleractinia precipitate aragonitic skeletons further suggesting they evolved in seawater with a high Mg/Ca ratio and that their mineralogy is linked to their environment. In order to determine how seawater chemistry influences host-symbiont interactions, we grew Pocillopora damicornis in seawater with elevated calcium and magnesium concentrations. Growth rates are higher than the control treatment when the Mg2+ concentration is increased by 200 ppm but are not significantly different than the control treatment when the Ca2+ concentration is increased by 200 ppm, suggesting that calcification is linked to the Mg2+ concentration of seawater. Growth rates are not, however, related to in-hospite symbiont density, which is similar in the control, +200 ppm Ca2+ and +200 ppm Mg2+ treatments. This similarity in symbiont density between treatments suggests that even when the chemistry of the surrounding seawater fluctuates, with respect to Ca2+ and Mg2+ ions, the coral host provides a stable environment in which the symbionts can reside. This preliminary work has implications for

  3. Solar astrophysics - Ghettosis from, or symbiosis with, stellar and galactic astrophysics

    NASA Technical Reports Server (NTRS)

    Pecker, J.-C.; Thomas, R. N.

    1976-01-01

    The purpose of the paper is to show how the solar-stellar symbiotic approach has led to the modeling of a star as a concentration of matter and energy. By 'solar-stellar symbiosis' is meant the philosophy of inve