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991.
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Claudio Hidalgo-Cantabrana Borja Sánchez Pablo álvarez-Martín Patricia López Noelia Martínez-álvarez Michele Delley Marc Martí Encarna Varela Ana Suárez María Antolín Francisco Guarner Bernard Berger Patricia Ruas-Madiedo Abelardo Margolles 《Applied and environmental microbiology》2015,81(23):7960-7968
Exopolysaccharides (EPS) are extracellular carbohydrate polymers synthesized by a large variety of bacteria. Their physiological functions have been extensively studied, but many of their roles have not yet been elucidated. We have sequenced the genomes of two isogenic strains of Bifidobacterium animalis subsp. lactis that differ in their EPS-producing phenotype. The original strain displays a nonmucoid appearance, and the mutant derived thereof has acquired a mucoid phenotype. The sequence analysis of their genomes revealed a nonsynonymous mutation in the gene Balat_1410, putatively involved in the elongation of the EPS chain. By comparing a strain from which this gene had been deleted with strains containing the wild-type and mutated genes, we were able to show that each strain displays different cell surface characteristics. The mucoid EPS synthesized by the strain harboring the mutation in Balat_1410 provided higher resistance to gastrointestinal conditions and increased the capability for adhesion to human enterocytes. In addition, the cytokine profiles of human peripheral blood mononuclear cells and ex vivo colon tissues suggest that the mucoid strain could have higher anti-inflammatory activity. Our findings provide relevant data on the function of Balat_1410 and reveal that the mucoid phenotype is able to alter some of the most relevant functional properties of the cells. 相似文献
994.
Jean‐Bernard Dongmo Champlain Djieto‐Lordon Pierre Ngassam 《African Journal of Ecology》2015,53(3):312-319
Evidence of sexual dimorphism in body size and the existence of morphological differences were studied in the yellow‐whiskered Greenbul Andropadus latirostris. We measured fresh body weight and seven linear parameters of external morphology in mature individuals of this species from three localities in Cameroon and two localities in Ghana. Based on general linear model analysis, we showed that males are significantly larger than females. We applied a discriminant analysis on eight morphometric parameters to create two discriminant functions, one for each country. The overall rate of well‐classified birds was 93.3% for Cameroon and 92.7% for Ghana. Wing length was the most accurate character for separating the sexes in both study areas. Significant sexual size dimorphism might be explained by sexual selection on male competitive ability and intraspecific competition. We also found morphological divergence in this species between the two study areas, including marked differences in size of the beak. This work provides statistical evidence of a substantial sexual size dimorphism in A. latirostris and geographic variation in morphology. 相似文献
995.
Gemma L. Holliday Amos Bairoch Pantelis G. Bagos Arnaud Chatonnet David J. Craik Robert D. Finn Bernard Henrissat Gerard Manning Nozomi Nagano Claire O'Donovan Neil D. Rawlings Milton Saier Ramanathan Sowdhamini Michael Spedding Narayanaswamy Srinivasan Gert Vriend Patricia C. Babbitt Alex Bateman 《Proteins》2015,83(6):1005-1013
As the volume of data relating to proteins increases, researchers rely more and more on the analysis of published data, thus increasing the importance of good access to these data that vary from the supplemental material of individual articles, all the way to major reference databases with professional staff and long‐term funding. Specialist protein resources fill an important middle ground, providing interactive web interfaces to their databases for a focused topic or family of proteins, using specialized approaches that are not feasible in the major reference databases. Many are labors of love, run by a single lab with little or no dedicated funding and there are many challenges to building and maintaining them. This perspective arose from a meeting of several specialist protein resources and major reference databases held at the Wellcome Trust Genome Campus (Cambridge, UK) on August 11 and 12, 2014. During this meeting some common key challenges involved in creating and maintaining such resources were discussed, along with various approaches to address them. In laying out these challenges, we aim to inform users about how these issues impact our resources and illustrate ways in which our working together could enhance their accuracy, currency, and overall value. Proteins 2015; 83:1005–1013. © 2015 The Authors. Proteins: Structure, Function, and Bioinformatics Published by Wiley Periodicals, Inc. 相似文献
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Climate change is expected to bring about profound rearrangement of ecological communities by affecting individual species distributions. The resulting communities arise from the idiosyncratic responses of species to future changes, which ultimately relate to both shrinking and expanding species ranges. While spatial patterns of colonisation and extirpation events have received great attention, the identification of specific drivers remains poorly explored. This study aims to investigate the relative contribution of species gain and loss to the turnover of fish assemblages in French rivers under future climate change, and to identify their principal drivers. Future projections of potential habitat suitability in 2080 derived from species distribution models for 40 fish species showed that colonisations and extirpations could play counterbalancing roles in the reshuffling of communities. Simultaneously, these two processes exhibited patchy spatial patterns, segregated along the longitudinal and altitudinal gradients, resulting in dramatic species turnover of ~ 60% of the current composition of species assemblages. Beyond the effect of topographic location, colonisations were found to be driven by temperature seasonality while extirpations were affected by modifications in both thermal and precipitation regimes. These results generate the possibility of developing ecosystem‐based management tools focused on the early identification of areas where particular species may be sensitive to climate changes. Disentangling the drivers of colonisation and extirpation processes provides ready‐to‐use information that may be easily integrated into conservation planning. This information could be used to identify potential hotspots of species gain and loss and to then compare these hotspots with newly favourable areas so as to consider their actual accessibility in order to facilitate future range shifts. 相似文献
998.
Yann Gibert Eric Samarut Emmanuel Pasco-Viel Laure Bernard Véronique Borday-Birraux Alexa Sadier Catherine Labbé Laurent Viriot Vincent Laudet 《Proceedings. Biological sciences / The Royal Society》2015,282(1802)
Small variations in signalling pathways have been linked to phenotypic diversity and speciation. In vertebrates, teeth represent a reservoir of adaptive morphological structures that are prone to evolutionary change. Cyprinid fish display an impressive diversity in tooth number, but the signals that generate such diversity are unknown. Here, we show that retinoic acid (RA) availability influences tooth number size in Cyprinids. Heterozygous adult zebrafish heterozygous for the cyp26b1 mutant that encodes an enzyme able to degrade RA possess an extra tooth in the ventral row. Expression analysis of pharyngeal mesenchyme markers such as dlx2a and lhx6 shows lateral, anterior and dorsal expansion of these markers in RA-treated embryos, whereas the expression of the dental epithelium markers dlx2b and dlx3b is unchanged. Our analysis suggests that changes in RA signalling play an important role in the diversification of teeth in Cyprinids. Our work illustrates that through subtle changes in the expression of rate-limiting enzymes, the RA pathway is an active player of tooth evolution in fish. 相似文献
999.
Elyse D. Bernard Kathy C. Nguyen Maria C. DeRosa Azam F. Tayabali Rocio Aranda-Rodriguez 《Analytical biochemistry》2015
A multiplexing bead-based platform provides an approach for the development of assays targeting specific analytes for biomonitoring and biosensing applications. Multi-Analyte Profiling (xMAP) assays typically employ a sandwich-type format using antibodies for the capture and detection of analytes of interest, and the system permits the simultaneous quantitation of multiple targets. In this study, an aptamer/antibody assay for the detection of C-reactive protein (CRP) was developed. CRP is an acute phase marker of inflammation whose elevated basal levels are correlated with an increased risk for a number of pathologies. For this assay, an RNA aptamer that binds CRP was conjugated to beads to act as the capture agent. Biotinylated anti-CRP antibody coupled to fluorescently labeled streptavidin was used for quantification of CRP. The detection limit of the CRP assay was 0.4 mg/L in diluted serum. The assay was then used to detect spiked CRP samples in the range of 0.4 to 10 mg/L in diluted serum with acceptable recoveries (extrapolated values of 70–130%), including that of a certified reference material (129% recovery). The successful incorporation of the CRP aptamer into this platform demonstrates that the exploration of other aptamer–target systems could increase the number of analytes measurable using xMAP-type assays. 相似文献
1000.