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A patent landscape on application of microorganisms in construction industry 全文
2017
Dapurkar, Dipti | Telang, Manasi
Construction biotechnology includes research and development of construction materials and processes that make use of various microbes. The present technology landscape gives a perspective on how microbes have been used in construction industry as cement and concrete additives by analyzing patents filed in this technology arena. All patents related to the technology of interest published globally to date have been reviewed. The earliest patent filing in this technology domain was recorded in the year 1958 and the patenting activity reached its peak around mid to late 1990s. The early technology was mainly focused on microbial polysaccharides and other metabolic products as additives. Year 2002 onwards, biomineralization has taken precedence over the other technologies with consistent patent filings indicating a shift in innovation focus. Japan has been the global leader with highest number of patents filed on application of microbes in construction industry. Southeast University, China has topped the patent assignee list with maximum number of filings followed by Kajima Corp. and Shin-Etsu Chemical Co., Ltd. Most patent applications have claimed microbe based bio-products. Construction-related microbial technologies are mainly based on activity of different microorganisms such as urease-producing, acidogenic, halophilic, alkaliphilic, nitrate and iron-reducing bacteria. Sporosarcina pasteurii has been the most widely used microbe for biomineralization.
显示更多 [+] 显示较少 [-]Diagnostic Evasion of Highly-Resistant Microorganisms: A Critical Factor in Nosocomial Outbreaks 全文
2017
Xuewei Zhou | Alexander W. Friedrich | Erik Bathoorn
Highly resistant microorganisms (HRMOs) may evade screening strategies used in routine diagnostics. Bacteria that have evolved to evade diagnostic tests may have a selective advantage in the nosocomial environment. Evasion of resistance detection can result from the following mechanisms: low-level expression of resistance genes not resulting in detectable resistance, slow growing variants, mimicry of wild-type-resistance, and resistance mechanisms that are only detected if induced by antibiotic pressure. We reviewed reports on hospital outbreaks in the Netherlands over the past 5 years. Remarkably, many outbreaks including major nation-wide outbreaks were caused by microorganisms able to evade resistance detection by diagnostic screening tests. We describe various examples of diagnostic evasion by several HRMOs and discuss this in a broad and international perspective. The epidemiology of hospital-associated bacteria may strongly be affected by diagnostic screening strategies. This may result in an increasing reservoir of resistance genes in hospital populations that is unnoticed. The resistance elements may horizontally transfer to hosts with systems for high-level expression, resulting in a clinically significant resistance problem. We advise to communicate the identification of HRMOs that evade diagnostics within national and regional networks. Such signaling networks may prevent inter-hospital outbreaks, and allow collaborative development of adapted diagnostic tests.
显示更多 [+] 显示较少 [-]Effect of fertilization on soil microorganisms in paddy rice systems – A meta-analysis 全文
2017
Geisseler, Daniel | Linquist, Bruce A. | Lazicki, Patricia A.
Soil microorganisms are considered a sensitive indicator of soil health and quality. In cropping systems, soil microorganisms are strongly affected by crop management, including the application of fertilizers. While studies in natural ecosystems have generally found that increased nitrogen (N) inputs decrease microbial biomass, microorganisms in soils under upland crops often benefit from mineral fertilizer input. Paddy rice soils, being flooded for part of the season, are dominated by different carbon (C) and N cycle processes and microbial communities than soils under upland crops. The objective of this study was to explore the effect of fertilizer on soil microorganisms in paddy rice systems in a meta-analysis of the peer-reviewed literature. Across all studies (n = 55), the addition of mineral fertilizer significantly increased microbial biomass carbon content (MBC) by 26% in paddy rice soils. Mineral fertilizer applications also increased soil organic carbon content (SOC) by 13%. The higher crop productivity with fertilization likely led to higher organic C inputs, which in turn increased SOC and MBC contents. The time of sampling within a season (pre-plant rice, in-season rice, post-harvest rice, or post-harvest rotational crop) did not significantly affect the response of MBC to mineral fertilizer. The positive effect of mineral fertilizer on MBC content did not differ between cropping systems with continuous rice and systems where paddy rice was grown in rotation with other crops. However, compared with upland cropping systems, the increase in the microbial biomass due to mineral fertilizer application is more pronounced in rice cropping systems, even when rice is grown in rotation with an upland crop. Differences in climate and soil oxygen availability likely explain the stronger response of soil microorganisms to mineral fertilizer input in paddy rice systems. Our analysis suggests that fertilization does not consistently select for specific microbial groups (e.g. gram positive or negative bacteria, fungi, actinomycetes) in paddy rice systems; however, it affects microbial community composition through changes in soil properties. How specific groups of microorganisms respond to mineral fertilization likely depends on environmental factors. Overall, our results suggest that in paddy rice systems the application of inorganic fertilizers increases SOC and MBC contents, both of which are important indicators of soil health.
显示更多 [+] 显示较少 [-]Cultivation of denitrifying anaerobic methane-oxidizing microorganisms in a continuous-flow sponge bioreactor 全文
2017
Hatamoto, Masashi | Satō, Takafumi | Nemoto, Sho | Yamaguchi, Takashi
Anaerobic treatment of sewage has many advantages; however, the effluent contains high levels of dissolved methane. In this study, we investigated the use of a closed-type downflow hanging sponge (DHS) reactor for application of the denitrifying anaerobic methane oxidation (DAMO) reaction for nitrogen and dissolved methane removal. When using nitrate, the DAMO reaction achieved a denitrification rate of 84.4 g N m⁻³ day⁻¹, which is close to that required for practical application of denitrification to anaerobic sewage treatment. The microbial community that developed in the DHS was investigated using16S rRNA, and novel species of DAMO bacteria affiliated with Group b of NC10 phylum were enriched. This contrasted with the results of previous studies in which the Candidatus Methylomirabilis oxyfera affiliated with Group a was enriched. The results obtained herein suggest that a post-treatment system for anaerobically treated sewage using a closed-type DHS reactor may become practical in the near future.
显示更多 [+] 显示较少 [-]Plants, microorganisms, and soil temperatures contribute to a decrease in methane fluxes on a drained Arctic floodplain 全文
2017
Kwon, Min Jung | Beulig, Felix | Ilie, Iulia | Wildner, Marcus | Küsel, Kirsten | Merbold, Lutz | Mahecha, Miguel D. | Zimov, Nikita | Zimov, Sergey A. | Heimann, Martin | Schuur, Edward A. G. | Kostka, Joel E. | Kolle, Olaf | Hilke, Ines | Göckede, Mathias
As surface temperatures are expected to rise in the future, ice‐rich permafrost may thaw, altering soil topography and hydrology and creating a mosaic of wet and dry soil surfaces in the Arctic. Arctic wetlands are large sources of CH₄, and investigating effects of soil hydrology on CH₄ fluxes is of great importance for predicting ecosystem feedback in response to climate change. In this study, we investigate how a decade‐long drying manipulation on an Arctic floodplain influences CH₄‐associated microorganisms, soil thermal regimes, and plant communities. Moreover, we examine how these drainage‐induced changes may then modify CH₄ fluxes in the growing and nongrowing seasons. This study shows that drainage substantially lowered the abundance of methanogens along with methanotrophic bacteria, which may have reduced CH₄ cycling. Soil temperatures of the drained areas were lower in deep, anoxic soil layers (below 30 cm), but higher in oxic topsoil layers (0–15 cm) compared to the control wet areas. This pattern of soil temperatures may have reduced the rates of methanogenesis while elevating those of CH₄ oxidation, thereby decreasing net CH₄ fluxes. The abundance of Eriophorum angustifolium, an aerenchymatous plant species, diminished significantly in the drained areas. Due to this decrease, a higher fraction of CH₄ was alternatively emitted to the atmosphere by diffusion, possibly increasing the potential for CH₄ oxidation and leading to a decrease in net CH₄ fluxes compared to a control site. Drainage lowered CH₄ fluxes by a factor of 20 during the growing season, with postdrainage changes in microbial communities, soil temperatures, and plant communities also contributing to this reduction. In contrast, we observed CH₄ emissions increased by 10% in the drained areas during the nongrowing season, although this difference was insignificant given the small magnitudes of fluxes. This study showed that long‐term drainage considerably reduced CH₄ fluxes through modified ecosystem properties.
显示更多 [+] 显示较少 [-]The application of powerful promoters to enhance gene expression in industrial microorganisms 全文
2017
Zhou, Shenghu | Du, Guocheng | Kang, Zhen | Li, Jianghua | Chen, Jian | Li, Huazhong | Zhou, Jingwen
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.
显示更多 [+] 显示较少 [-]DOSTĘPNOŚĆ ŚRODKÓW OCHRONY ROŚLIN ZAWIERAJĄCYCH MIKROORGANIZMY W POLSCE I INNYCH PAŃSTWACH CZŁONKOWSKICH UNII EUROPEJSKIEJ 全文
2017
Matyjaszczyk, Ewa
Plant protection products containing microorganisms may constitute a worthy tool in integrated pestmanagement. There are 37 different microorganisms (21 fungi, 11 bacteria and 5 viruses) approved for use inplant protection in EU. The majority of microorganism – 22 are approved as fungicides, 13 as insecticides and 2as nematicides. Their utilization in member states is however very differentiated. No Member State does use thefull pool of approved microorganisms. The biggest diversity of microbial products is registered in France andItaly – where respectively 22 and 21 microorganisms are used, while the lowest in Latvia – only 1. On the Polishmarket there are 9 microbial products containing 6 different microorganisms.
显示更多 [+] 显示较少 [-]La cytométrie appliquée aux mircoorganismes du vin 全文
2017
Cédric, Longin | Clément, Petitgonnet | Michèle, Guilloux-Benatier | Sandrine, Rousseaux | Hervé, Alexandre
La cytométrie appliquée aux mircoorganismes du vin 全文
2017
Cédric, Longin | Clément, Petitgonnet | Michèle, Guilloux-Benatier | Sandrine, Rousseaux | Hervé, Alexandre
Flow cytometry (FCM) is a powerful technique allowing detection and enumeration of microbial populations in food and during food process. Thanks to the fluorescent dyes used and specific probes, FCM provides information about cell physiological state and allows enumeration of a microorganism in a mixed culture. Thus, this technique is increasingly used to quantify pathogen, spoilage microorganisms and microorganisms of interest. Since one decade, FCM applications to the wine field increase greatly to determine population and physiological state of microorganisms performing alcoholic and malolactic fermentations. We will describe FCM principles and the available techniques allowing quantification of wine microorganisms by FCM using fluorescent dyes. Different examples of FCM analysis regarding monitoring of alcoholic fermentation, malolactic fermentation (total population, viable population, physiological state), specific detection and quantification of spoilage microorganisms like Brettanomyces will be presented.
显示更多 [+] 显示较少 [-]La cytométrie appliquée aux mircoorganismes du vin 全文
2017
Longin Cédric | Petitgonnet Clément | Guilloux-Benatier Michèle | Rousseaux Sandrine | Alexandre Hervé
Flow cytometry (FCM) is a powerful technique allowing detection and enumeration of microbial populations in food and during food process. Thanks to the fluorescent dyes used and specific probes, FCM provides information about cell physiological state and allows enumeration of a microorganism in a mixed culture. Thus, this technique is increasingly used to quantify pathogen, spoilage microorganisms and microorganisms of interest. Since one decade, FCM applications to the wine field increase greatly to determine population and physiological state of microorganisms performing alcoholic and malolactic fermentations. We will describe FCM principles and the available techniques allowing quantification of wine microorganisms by FCM using fluorescent dyes. Different examples of FCM analysis regarding monitoring of alcoholic fermentation, malolactic fermentation (total population, viable population, physiological state), specific detection and quantification of spoilage microorganisms like Brettanomyces will be presented.
显示更多 [+] 显示较少 [-]Ecosystem fluxes of hydrogen in a mid‐latitude forest driven by soil microorganisms and plants 全文
2017
Meredith, Laura K. | Commane, Róisín | Keenan, Trevor F. | Klosterman, Stephen T. | Munger, J William | Templer, Pamela H. | Tang, Jianwu | Wofsy, Steven C. | Prinn, Ronald G.
Molecular hydrogen (H₂) is an atmospheric trace gas with a large microbe‐mediated soil sink, yet cycling of this compound throughout ecosystems is poorly understood. Measurements of the sources and sinks of H₂ in various ecosystems are sparse, resulting in large uncertainties in the global H₂ budget. Constraining the H₂ cycle is critical to understanding its role in atmospheric chemistry and climate. We measured H₂ fluxes at high frequency in a temperate mixed deciduous forest for 15 months using a tower‐based flux‐gradient approach to determine both the soil‐atmosphere and the net ecosystem flux of H₂. We found that Harvard Forest is a net H₂ sink (−1.4 ± 1.1 kg H₂ ha⁻¹) with soils as the dominant H₂ sink (−2.0 ± 1.0 kg H₂ ha⁻¹) and aboveground canopy emissions as the dominant H₂ source (+0.6 ± 0.8 kg H₂ ha⁻¹). Aboveground emissions of H₂ were an unexpected and substantial component of the ecosystem H₂ flux, reducing net ecosystem uptake by 30% of that calculated from soil uptake alone. Soil uptake was highly seasonal (July maximum, February minimum), positively correlated with soil temperature and negatively correlated with environmental variables relevant to diffusion into soils (i.e., soil moisture, snow depth, snow density). Soil microbial H₂ uptake was correlated with rhizosphere respiration rates (r = 0.8, P < 0.001), and H₂ metabolism yielded up to 2% of the energy gleaned by microbes from carbon substrate respiration. Here, we elucidate key processes controlling the biosphere–atmosphere exchange of H₂ and raise new questions regarding the role of aboveground biomass as a source of atmospheric H₂ and mechanisms linking soil H₂ and carbon cycling. Results from this study should be incorporated into modeling efforts to predict the response of the H₂ soil sink to changes in anthropogenic H₂ emissions and shifting soil conditions with climate and land‐use change.
显示更多 [+] 显示较少 [-]Isolation and characterization of Arctic microorganisms decomposing bioplastics 全文
2017
Aneta K. Urbanek | Waldemar Rymowicz | Mateusz C. Strzelecki | Waldemar Kociuba | Łukasz Franczak | Aleksandra M. Mirończuk
Abstract The increasing amount of plastic waste causes significant environmental pollution. In this study, screening of Arctic microorganisms which are able to degrade bioplastics was performed. In total, 313 microorganisms were isolated from 52 soil samples from the Arctic region (Spitsbergen). Among the isolated microorganisms, 121 (38.66%) showed biodegradation activity. The ability of clear zone formation on emulsified poly(butylene succinate-co-adipate) (PBSA) was observed for 116 microorganisms (95.87%), on poly(butylene succinate) (PBS) for 73 microorganisms (60.33%), and on poly(ɛ-caprolactone) (PCL) for 102 microorganisms (84.3%). Moreover, the growth of microorganisms on poly(lactic acid) (PLA) agar plates was observed for 56 microorganisms (46.28%). Based on the 16S rRNA sequence, 10 bacterial strains which showed the highest ability for biodegradation were identified as species belonging to Pseudomonas sp. and Rhodococcus sp. The isolated fungal strains were tested for polycaprolactone films and commercial corn and potato starch bags degradation under laboratory conditions. Strains 16G (based on the analysis of a partial 18S rRNA sequence, identified as Clonostachys rosea) and 16H (identified as Trichoderma sp.) showed the highest capability for biodegradation. A particularly high capability for biodegradation was observed for the strain Clonostachys rosea, which showed 100% degradation of starch films and 52.91% degradation of PCL films in a 30-day shake flask experiment. The main advantage of the microorganisms isolated from Arctic environment is the ability to grow at low temperature and efficient biodegradation under this condition. The data suggest that C. rosea can be used in natural and laboratory conditions for degradations of bioplastics.
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