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141.
Karsenti E Acinas SG Bork P Bowler C De Vargas C Raes J Sullivan M Arendt D Benzoni F Claverie JM Follows M Gorsky G Hingamp P Iudicone D Jaillon O Kandels-Lewis S Krzic U Not F Ogata H Pesant S Reynaud EG Sardet C Sieracki ME Speich S Velayoudon D Weissenbach J Wincker P;Tara Oceans Consortium 《PLoS biology》2011,9(10):e1001177
The structure, robustness, and dynamics of ocean plankton ecosystems remain poorly understood due to sampling, analysis, and computational limitations. The Tara Oceans consortium organizes expeditions to help fill this gap at the global level. 相似文献
142.
143.
Monier JM Demanèche S Delmont TO Mathieu A Vogel TM Simonet P 《Current opinion in microbiology》2011,14(3):229-235
The ongoing development of metagenomic approaches is providing the means to explore antibiotic resistance in nature and address questions that could not be answered previously with conventional culture-based strategies. The number of available environmental metagenomic sequence datasets is rapidly expanding and henceforth offer the ability to gain a more comprehensive understanding of antibiotic resistance at the global scale. Although there is now evidence that the environment constitutes a vast reservoir of antibiotic resistance gene determinants (ARGDs) and that the majority of ARGDs acquired by human pathogens may have an environmental origin, a better understanding of their diversity, prevalence and ecological significance may help predict the emergence and spreading of newly acquired resistances. Recent applications of metagenomic approaches to the study of ARGDs in natural environments such as soil should help overcome challenges concerning expanding antibiotic resistances. 相似文献
144.
Ante Žuljević Thierry Thibaut Marija Despalatović Jean-Michel Cottalorda Vedran Nikolić Ivan Cvitković Boris Antolić 《Biological invasions》2011,13(10):2303-2308
Here we present the first observation of the impact of the invasive Caulerpa racemosa var. cylindracea on native photophilic sponge species in the Adriatic Sea, with special focus on Sarcotragus spinosulus. Caulerpa racemosa var. cylindracea is able to completely overgrow the sponge, developing an exceptionally thick canopy with a maximum measured density of 1,887 m
of stolons m−2 and 40,561 fronds m−2. Necrosis of the sponge surface was significantly correlated with the algal dry biomass, frond number and stolon length.
Dense algal canopy, penetration of the algal stolon and rhizoids into the sponge oscula and covering of the ostiae probably
diminishes the seawater circulation through the sponge and consequently results in its smothering and even death. We suggest
that chemotropism is the reason why C. racemosa penetrates the sponge oscula and establishes such dense canopy on the sponge. 相似文献
145.
146.
The button mushroom Agaricus bisporus commercially cultivated requires 16-19 °C during the fruiting period. Wild strains are also present in natural habitat, and in light of their wide range of geographic distribution reported, from boreal region to tropical region, questions on the development adaptation to temperature arose. Isolates from various geographic areas were screened for their ability to fruit at higher temperature (FHT ability) than commercial cultivars. The FHT trait discriminated at the varietal rank. Agaricus bisporus var. eurotetrasporus was unable to develop any sporophores whilst A. bisporus var. burnettii adapted perfectly to 25 °C for fruiting, suggesting that the FHT ability is a fixed trait in these varieties. In contrast, FHT ability of A. bisporus var. bisporus appeared variable and correlated neither with climate/microclimate nor with habitat. However, FHT ability taken as a whole appeared higher in North American populations than in European ones. Some A. bisporus var. bisporus isolates revealed a good potential for cultivation at 25 °C. 相似文献
147.
Hiroyuki Ogata Jessica Ray Kensuke Toyoda Ruth-Anne Sandaa Keizo Nagasaki Gunnar Bratbak Jean-Michel Claverie 《The ISME journal》2011,5(7):1143-1151
MutS proteins are ubiquitous in cellular organisms and have important roles in DNA mismatch repair or recombination. In the virus world, the amoeba-infecting Mimivirus, as well as the recently sequenced Cafeteria roenbergensis virus are known to encode a MutS related to the homologs found in octocorals and ɛ-proteobacteria. To explore the presence of MutS proteins in other viral genomes, we performed a genomic survey of four giant viruses (‘giruses'') (Pyramimonas orientalis virus (PoV), Phaeocystis pouchetii virus (PpV), Chrysochromulina ericina virus (CeV) and Heterocapsa circularisquama DNA virus (HcDNAV)) that infect unicellular marine algae. Our analysis revealed the presence of a close homolog of Mimivirus MutS in all the analyzed giruses. These viral homologs possess a specific domain structure, including a C-terminal HNH-endonuclease domain, defining the new MutS7 subfamily. We confirmed the presence of conserved mismatch recognition residues in all members of the MutS7 subfamily, suggesting their role in DNA mismatch repair rather than DNA recombination. PoV and PpV were found to contain an additional type of MutS, which we propose to call MutS8. The MutS8 proteins in PoV and PpV were found to be closely related to homologs from ‘Candidatus Amoebophilus asiaticus'', an obligate intracellular amoeba-symbiont belonging to the Bacteroidetes. Furthermore, our analysis revealed that MutS7 and MutS8 are abundant in marine microbial metagenomes and that a vast majority of these environmental sequences are likely of girus origin. Giruses thus seem to represent a major source of the underexplored diversity of the MutS family in the microbial world. 相似文献
148.
Levels and determinants of inflammatory biomarkers in a Swiss population-based sample (CoLaus study)
Marques-Vidal P Bochud M Bastardot F Lüscher T Ferrero F Gaspoz JM Paccaud F Urwyler A von Känel R Hock C Waeber G Preisig M Vollenweider P 《PloS one》2011,6(6):e21002
Objective
to assess the levels and determinants of interleukin (IL)-1β, IL-6, tumour necrosis factor (TNF)-α and C-reactive protein (CRP) in a healthy Caucasian population.Methods
population sample of 2884 men and 3201 women aged 35 to 75. IL-1β, IL-6 and TNF-α were assessed by a multiplexed particle-based flow cytometric assay and CRP by an immunometric assay.Results
Spearman rank correlations between duplicate cytokine measurements (N = 80) ranged between 0.89 and 0.96; intra-class correlation coefficients ranged between 0.94 and 0.97, indicating good reproducibility. Among the 6085 participants, 2289 (37.6%), 451 (7.4%) and 43 (0.7%) had IL-1β, IL-6 and TNF-α levels below detection limits, respectively. Median (interquartile range) for participants with detectable values were 1.17 (0.48–3.90) pg/ml for IL-1β; 1.47 (0.71–3.53) pg/ml for IL-6; 2.89 (1.82–4.53) pg/ml for TNF-α and 1.3 (0.6–2.7) ng/ml for CRP. On multivariate analysis, greater age was the only factor inversely associated with IL-1β levels. Male sex, increased BMI and smoking were associated with greater IL-6 levels, while no relationship was found for age and leisure-time PA. Male sex, greater age, increased BMI and current smoking were associated with greater TNF-α levels, while no relationship was found with leisure-time PA. CRP levels were positively related to age, BMI and smoking, and inversely to male sex and physical activity.Conclusion
Population-based levels of several cytokines were established. Increased age and BMI, and to a lesser degree sex and smoking, significantly and differentially impact cytokine levels, while leisure-time physical activity has little effect. 相似文献149.
Interactions between animal behaviour and the environment are both shaping observed habitat use. Despite the importance of inter-specific interactions on the habitat use performed by individuals, most previous analyses have focused on case studies of single species. By focusing on two sympatric populations of large herbivores with contrasting body size, we went one step beyond by studying variation in home range size and identifying the factors involved in such variation, to define how habitat features such as resource heterogeneity, resource quality, and openness created by hurricane or forest managers, and constraints may influence habitat use at the individual level. We found a large variability among individual's home range size in both species, particularly in summer. Season appeared as the most important factor accounting for observed variation in home range size. Regarding habitat features, we found that (i) the proportion of area damaged by the hurricane was the only habitat component that inversely influenced roe deer home range size, (ii) this habitat type also influenced both diurnal and nocturnal red deer home range sizes, (iii) home range size of red deer during the day was inversely influenced by the biomass of their preferred plants, as were both diurnal and nocturnal core areas of the red deer home range, and (iv) we do not find any effect of resource heterogeneity on home range size in any case. Our results suggest that a particular habitat type (i.e. areas damaged by hurricane) can be used by individuals of sympatric species because it brings both protected and dietary resources. Thus, it is necessary to maintain the openness of these areas and to keep animal density quite low as observed in these hunted populations to limit competition between these sympatric populations of herbivores. 相似文献
150.
Matar-Merheb R Rhimi M Leydier A Huché F Galián C Desuzinges-Mandon E Ficheux D Flot D Aghajari N Kahn R Di Pietro A Jault JM Coleman AW Falson P 《PloS one》2011,6(3):e18036