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131.
Maryam Yazdani Foshtomi Ulrike Braeckman Sofie Derycke Melanie Sapp Dirk Van Gansbeke Koen Sabbe Anne Willems Magda Vincx Jan Vanaverbeke 《PloS one》2015,10(6)
Objectives
The marine benthic nitrogen cycle is affected by both the presence and activity of macrofauna and the diversity of N-cycling microbes. However, integrated research simultaneously investigating macrofauna, microbes and N-cycling is lacking. We investigated spatio-temporal patterns in microbial community composition and diversity, macrofaunal abundance and their sediment reworking activity, and N-cycling in seven subtidal stations in the Southern North Sea.Spatio-Temporal Patterns of the Microbial Communities
Our results indicated that bacteria (total and β-AOB) showed more spatio-temporal variation than archaea (total and AOA) as sedimentation of organic matter and the subsequent changes in the environment had a stronger impact on their community composition and diversity indices in our study area. However, spatio-temporal patterns of total bacterial and β-AOB communities were different and related to the availability of ammonium for the autotrophic β-AOB. Highest bacterial richness and diversity were observed in June at the timing of the phytoplankton bloom deposition, while richness of β-AOB as well as AOA peaked in September. Total archaeal community showed no temporal variation in diversity indices.Macrofauna, Microbes and the Benthic N-Cycle
Distance based linear models revealed that, independent from the effect of grain size and the quality and quantity of sediment organic matter, nitrification and N-mineralization were affected by respectively the diversity of metabolically active β-AOB and AOA, and the total bacteria, near the sediment-water interface. Separate models demonstrated a significant and independent effect of macrofaunal activities on community composition and richness of total bacteria, and diversity indices of metabolically active AOA. Diversity of β-AOB was significantly affected by macrofaunal abundance. Our results support the link between microbial biodiversity and ecosystem functioning in marine sediments, and provided broad correlative support for the hypothesis that this relationship is modulated by macrofaunal activity. We hypothesized that the latter effect can be explained by their bioturbating and bio-irrigating activities, increasing the spatial complexity of the biogeochemical environment. 相似文献132.
Jeanne Tonnabel Agnès Mignot Emmanuel J. P. Douzery Anthony G. Rebelo Frank M. Schurr Jeremy Midgley Nicola Illing Fabienne Justy Denis Orcel Isabelle Olivieri 《Evolution; international journal of organic evolution》2014,68(10):2775-2792
Natural selection is expected to cause convergence of life histories among taxa as well as correlated evolution of different life‐history traits. Here, we quantify the extent of convergence of five key life‐history traits (adult fire survival, seed storage, degree of sexual dimorphism, pollination mode, and seed‐dispersal mode) and test hypotheses about their correlated evolution in the genus Leucadendron (Proteaceae) from the fire‐prone South African fynbos. We reconstructed a new molecular phylogeny of this highly diverse genus that involves more taxa and molecular markers than previously. This reconstruction identifies new clades that were not detected by previous molecular study and morphological classifications. Using this new phylogeny and robust methods that account for phylogenetic uncertainty, we show that the five life‐history traits studied were labile during the evolutionary history of the genus. This diversity allowed us to tackle major questions about the correlated evolution of life‐history strategies. We found that species with longer seed‐dispersal distances tended to evolve lower pollen‐dispersal distance, that insect‐pollinated species evolved decreased sexual dimorphism, and that species with a persistent soil seed‐bank evolved toward reduced fire‐survival ability of adults. 相似文献
133.
Rayda Ben-Ayed Cinderella Sans-Grout Fabienne Moreau Naziha Grati-Kamoun Ahmed Rebai 《Biochemical genetics》2014,52(5-6):258-268
We used eight informative microsatellite markers for fingerprinting and evaluation of genetic similarity among 15 Tunisian olive (Olea europaea L.) cultivars and two feral unknown trees named Soulela 1 and Soulela 2. Thirty-one alleles were revealed, and the number of alleles per SSR varied from 2 (UDO12) to 6 (GAPU71A). Cluster analysis grouped cultivars into three main clusters. The two unknown varieties could not be reliably classified into any of these cultivar groups. SSR analysis indicated the presence of three erroneous denominations of cultivars. We resolved two synonymy cases (Zalmati and Chemlali; Rkhami and Chetoui) and one case of homonymy (Chemlali Tataouine). Genetic analyses of DNA extracted from leaves, oils, and embryos of the two unknown cultivars and the two major Tunisian olive cultivars (Chemlali and Chetoui) were also studied. We conclude that the reliable identification of these two feral cultivars needs to be addressed by a larger set of markers. 相似文献
134.
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136.
Stefano Crosignani Agnes Bombrun David Covini Maurizio Maio Delphine Marin Anna Quattropani Dominique Swinnen Don Simpson Wolfgang Sauer Bernard Françon Thierry Martin Yves Cambet Anthony Nichols Isabelle Martinou Fabienne Burgat-Charvillon Delphine Rivron Cristina Donini Olivier Schott Valerie Eligert Laurence Novo-Perez Jean-François Arrighi 《Bioorganic & medicinal chemistry letters》2010,20(5):1516-1519
The discovery of a novel series of S1P1 agonists is described. Starting from a micromolar HTS positive, iterative optimization gave rise to several single-digit nanomolar S1P1 agonists. The compounds were able to induce internalization of the S1P1 receptor, and a selected compound was shown to be able to induce lymphopenia in mice after oral dosing. 相似文献
137.
Lívia Santos Lima Karina Peres Gramacho José Luis Pires Didier Clement Uilson Vanderlei Lopes Nicolas Carels Abelmon da Silva Gesteira Fernanda Amato Gaiotto Júlio Cézar de Mattos Cascardo Fabienne Micheli 《Tree Genetics & Genomes》2010,6(5):663-676
In this study, we report results of the detection and analysis of SSR markers derived of cacao–Moniliophthora perniciosa expressed sequence tags (ESTs) in relation to cacao resistance to witches’ broom disease (WBD), and we compare the polymorphism
of those ESTs (EST-simple sequence repeat (SSR)) with classical neutral SSR markers. A total of 3,487 ESTs was used in this
investigation. SSRs were identified in 430 sequences: 277 from the resistant genotype TSH 1188 and 153 from the susceptible
one Catongo, totalizing 505 EST-SSRs with three types of motifs: dinucleotides (72.1%), trinucleotides (27.3%), and tetranucleotides
(0.6%). EST-SSRs were classified into 16 main categories; most of the EST-SSRs belonged to “Unknown function” and “No homology”
categories (45.82%). A high frequency of SSRs was found in the 5’UTR and in the ORF (about 27%) and a low frequency was observed
in the 3’UTR (about 8%). Forty-nine EST-SSR primers were designed and evaluated in 21 cacao accessions, 12 revealed polymorphism,
having 47 alleles in total, with an average of 3.92 alleles per locus. On the other hand, the 11 genomic SSR markers revealed
a total of 47 alleles, with an average of 5.22 alleles per locus. The association of EST-SSR with the genomic SSR enhanced
the analysis of genetic distance among the genotypes. Among the 12 polymorphic EST-SSR markers, two were mapped on the F2 Sca 6 × ICS 1 population reference for WBD resistance. 相似文献
138.
Soline Aubry Baptiste Aussedat Diane Delaroche Chen-Yu Jiao Gérard Bolbach Solange Lavielle Gérard Chassaing Sandrine Sagan Fabienne Burlina 《生物化学与生物物理学报:生物膜》2010,1798(12):2182-2189
This review summarizes the contribution of MALDI-TOF mass spectrometry in the study of cell-penetrating peptide (CPP) internalization in eukaryote cells. This technique was used to measure the efficiency of cell-penetrating peptide cellular uptake and cargo delivery and to analyze carrier and cargo intracellular degradation. The impact of thiol-containing membrane proteins on the internalization of CPP–cargo disulfide conjugates was also evaluated by combining MALDI-TOF MS with simple thiol-specific reactions. This highlighted the formation of cross-linked species to cell-surface proteins that either remained trapped in the cell membrane or led to intracellular delivery. MALDI-TOF MS is thus a powerful tool to dissect CPP internalization mechanisms. 相似文献
139.
Borgonie G Dierick M Houthoofd W Willems M Jacobs P Bert W 《The Biological bulletin》2010,219(3):268-276
Organisms living in extreme habitats require costly adaptations to cope with these conditions. Among the suggested potential benefits that trade off these costs is refuge from predation. To study these interactions in extreme environments, samples were taken in the cave Cueva de Villa Luz, Tabasco, Mexico, where more than 32 subterranean springs, some H(2)S rich, rise from the floor. Hydrogen sulfide gas plus oxygen is absorbed by freshwater, and oxidation forms concentrated sulfuric acid. Snottites, whitish hollow mucous tubes, hang from the ceiling of the cave. Fluid drops from these snottites were recorded as having pH values of 0-3. We report the discovery of a new species of nematode that thrives in the highly acidic environment of the snottite. Micro CT scan of snottites reveals a complex interaction between the acidic snottite, nematodes, and abundant nematode-eating mites. The nematode adaptation to low pH probably protects them against mite predation, for which nematodes are most likely the most important source of carbon in this sulfur-driven ecosystem. 相似文献
140.
Laurence Dutot Pascaline Lécorché Fabienne Burlina Rodrigue Marquant Vanessa Point Sandrine Sagan Gérard Chassaing Jean-Maurice Mallet Solange Lavielle 《Journal of chemical biology》2010,3(2):51-65
Cell-penetrating peptides (CPPs), which are usually short basic peptides, are able to cross cell membranes and convey bioactive
cargoes inside cells. CPPs have been widely used to deliver inside cells peptides, proteins, and oligonucleotides; however,
their entry mechanisms still remain controversial. A major problem concerning CPPs remains their lack of selectivity to target
a specific type of cell and/or an intracellular component. We have previously shown that myristoylation of one of these CPPs
affected the intracellular distribution of the cargo. We report here on the synthesis of glycosylated analogs of the cell-penetrating
peptide (R6/W3): Ac-RRWWRRWRR-NH2. One, two, or three galactose(s), with or without a spacer, were introduced into the sequence of this nonapeptide via a triazole link, the Huisgen reaction being achieved on a solid support. Four of these glycosylated CPPs were coupled via a disulfide bridge to the proapoptotic KLAK peptide, (KLAKLAKKLAKLAK), which alone does not enter into cells. The effect
on cell viability and the uptake efficiency of different glycosylated conjugates were studied on CHO cells and were compared
to those of the nonglycosylated conjugates: (R6/W3)S-S-KLAK and penetratinS-S-KLAK. We show that glycosylation significantly
increases the cell viability of CHO cells compared to the nonglycosylated conjugates and concomitantly decreases the internalization
of the KLAK cargo. These results suggest that glycosylation of CPP may be a key point in targeting specific cells. 相似文献