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101.
Tobias Schwarzmüller Biao Ma Ekkehard Hiller Fabian Istel Michael Tscherner Sascha Brunke Lauren Ames Arnaud Firon Brian Green Vitor Cabral Marina Marcet-Houben Ilse D. Jacobsen Jessica Quintin Katja Seider Ingrid Frohner Walter Glaser Helmut Jungwirth Sophie Bachellier-Bassi Murielle Chauvel Ute Zeidler Dominique Ferrandon Toni Gabaldón Bernhard Hube Christophe d'Enfert Steffen Rupp Brendan Cormack Ken Haynes Karl Kuchler 《PLoS pathogens》2014,10(6)
The opportunistic fungal pathogen Candida glabrata is a frequent cause of candidiasis, causing infections ranging from superficial to life-threatening disseminated disease. The inherent tolerance of C. glabrata to azole drugs makes this pathogen a serious clinical threat. To identify novel genes implicated in antifungal drug tolerance, we have constructed a large-scale C. glabrata deletion library consisting of 619 unique, individually bar-coded mutant strains, each lacking one specific gene, all together representing almost 12% of the genome. Functional analysis of this library in a series of phenotypic and fitness assays identified numerous genes required for growth of C. glabrata under normal or specific stress conditions, as well as a number of novel genes involved in tolerance to clinically important antifungal drugs such as azoles and echinocandins. We identified 38 deletion strains displaying strongly increased susceptibility to caspofungin, 28 of which encoding proteins that have not previously been linked to echinocandin tolerance. Our results demonstrate the potential of the C. glabrata mutant collection as a valuable resource in functional genomics studies of this important fungal pathogen of humans, and to facilitate the identification of putative novel antifungal drug target and virulence genes. 相似文献
102.
Characterization of nine polymorphic microsatellite loci in the fungus Botrytis cinerea (Ascomycota)
E. Fournier T. Giraud A. Loiseau D. Vautrin A. Estoup M. Solignac J. M. Cornuet Y. Brygoo 《Molecular ecology resources》2002,2(3):253-255
Nine microsatellite markers were characterized in the fungus Botrytis cinerea. Genomic DNA sequences from the partial sequencing of 12 000 bacterial artificial chromosome (BAC) clones, were screened by BLAST for various microsatellite motives, and primer pairs were designed. Cross‐amplification and polymorphism were assessed on 49 isolates from B. cinerea and two related species, collected from natural populations on several plants and locations. 相似文献
103.
Identification of essential genes in the human fungal pathogen Aspergillus fumigatus by transposon mutagenesis 总被引:4,自引:0,他引:4
The opportunistic pathogen Aspergillus fumigatus is the most frequent cause of deadly airborne fungal infections in developed countries. In order to identify novel antifungal-drug targets, we investigated the genome of A. fumigatus for genes that are necessary for efficient fungal growth. An artificial A. fumigatus diploid strain with one copy of an engineered impala160 transposon from Fusarium oxysporum integrated into its genome was used to generate a library of diploid strains by random in vivo transposon mutagenesis. Among 2,386 heterozygous diploid strains screened by parasexual genetics, 1.2% had a copy of the transposable element integrated into a locus essential for A. fumigatus growth. Comparison of genomic sequences flanking impala160 in these mutants with that of the genome of A. fumigatus allowed the characterization of 20 previously uncharacterized A. fumigatus genes. Among these, homologues of genes essential for Saccharomyces cerevisiae growth have been identified, as well as genes that do not have homologues in other fungal species. These results confirm that heterologous transposition using the transposable element impala is a powerful tool for functional genomics in ascomycota, and they pave the way for defining the complete set of essential genes in A. fumigatus, the first step toward target-based development of new antifungal drugs. 相似文献
104.
105.
Massive Sorghum Collection Genotyped with SSR Markers to Enhance Use of Global Genetic Resources 总被引:2,自引:0,他引:2
Claire Billot Punna Ramu Sophie Bouchet Jacques Chantereau Monique Deu Laetitia Gardes Jean-Louis Noyer Jean-Fran?ois Rami Ronan Rivallan Yu Li Ping Lu Tianyu Wang Rolf T. Folkertsma Elizabeth Arnaud Hari D. Upadhyaya Jean-Christophe Glaszmann C. Thomas Hash 《PloS one》2013,8(4)
Large ex situ collections require approaches for sampling manageable amounts of germplasm for in-depth characterization and use. We present here a large diversity survey in sorghum with 3367 accessions and 41 reference nuclear SSR markers. Of 19 alleles on average per locus, the largest numbers of alleles were concentrated in central and eastern Africa. Cultivated sorghum appeared structured according to geographic regions and race within region. A total of 13 groups of variable size were distinguished. The peripheral groups in western Africa, southern Africa and eastern Asia were the most homogeneous and clearly differentiated. Except for Kafir, there was little correspondence between races and marker-based groups. Bicolor, Caudatum, Durra and Guinea types were each dispersed in three groups or more. Races should therefore better be referred to as morphotypes. Wild and weedy accessions were very diverse and scattered among cultivated samples, reinforcing the idea that large gene-flow exists between the different compartments. Our study provides an entry to global sorghum germplasm collections. Our reference marker kit can serve to aggregate additional studies and enhance international collaboration. We propose a core reference set in order to facilitate integrated phenotyping experiments towards refined functional understanding of sorghum diversity. 相似文献
106.
Faure C Raynaud-Simon A Ferry A Daugé V Cynober L Aussel C Moinard C 《Amino acids》2012,42(4):1425-1433
Protein energy malnutrition in the elderly causes preferential loss of muscle mass which is associated with poor functional
states. Leucine and citrulline are able to stimulate muscle protein synthesis in aged rats but no study has been undertaken
to evaluate their effect on muscle function. Sprague–Dawley male rats aged 23 months were used in the experiment. Part of
them were subjected to a dietary restriction for 12 weeks and then assigned to four groups: a group was euthanized (restricted
group), and the others were refed for 1 week with either a leucine-, a citrulline-supplemented diet, or a standard diet. The
other rats were fed ad libitum. Muscle mass and motor activity significantly increased during the refeeding with either leucine
or citrulline (respectively, +51 and +37% for muscle mass, P < 0.05). The improvement of muscle mass and of motor activity induced by leucine and citrulline was highly associated with
that of maximal tetanic isometric force (r = 0.769, P < 0.0001; r = 0.389, P < 0.05, respectively) but only leucine improved maximal tetanic isometric force (+101%, P < 0.05). In conclusion, this is the first study to demonstrate the ability of two amino acids (leucine and citrulline) to
modulate muscle function. 相似文献
107.
Marie J. Richard Veronique Ducros Michel Rorêt Josiane Arnaud Charles Coudray Michèle Fusselier Alain Favier 《Biological trace element research》1993,39(2-3):149-159
In six chronic dialyzed uremic patients, an intravenous sodium selenite (Se 50 μg during 5 wk and then 100 μg) and zinc gluconate
(Zn 5 mg) supplementation was performed during 20 wk at each dialysis session three times weekly. Before supplementation,
plasma Se and Zn, plasma and erythrocytes (RBC) antioxidant metalloenzymes glutathione peroxidase (GPX), and superoxide dismutase
(SOD) were significantly decreased, whereas lipid peroxidation (as thiobarbituric acid reactants TBARs) was increased. To
obtain a significative change in plasma selenium, we had to use an Se dose of 100 μg/dialysis session. Then, treatment-increased
plasma Se (from 0.58 ±0.09 to 0.89±0.16 μmol/L) led to a repletion of RBC-GPX (from 29.6±6 to 43±5.8 U/g Hb) and increased
plasma GPX levels (from 62±13 to 151±43 U/L). Plasma Zn and RBC-SOD did not vary significantly. The change of TBARs was not
observed between wk 1 and 4. They decreased significantly between wk 4 (4.80±0.21μmol/L) and wk 20 (4.16±0.26 μmol/L). We
noted a low correlation between TBARs and plasma GPX. A strong correlation was observed between Se and plasma GPX. The reversal
of Se deficiencies should reduce oxidative damage observed in these patients. 相似文献
108.
109.
Jrme Mounier Christophe Monnet Tatiana Vallaeys Roger Arditi Anne-Sophie Sarthou Arnaud Hlias Franoise Irlinger 《Applied microbiology》2008,74(1):172-181
The interactions that occur during the ripening of smear cheeses are not well understood. Yeast-yeast interactions and yeast-bacterium interactions were investigated within a microbial community composed of three yeasts and six bacteria found in cheese. The growth dynamics of this community was precisely described during the ripening of a model cheese, and the Lotka-Volterra model was used to evaluate species interactions. Subsequently, the effects on ecosystem functioning of yeast omissions in the microbial community were evaluated. It was found both in the Lotka-Volterra model and in the omission study that negative interactions occurred between yeasts. Yarrowia lipolytica inhibited mycelial expansion of Geotrichum candidum, whereas Y. lipolytica and G. candidum inhibited Debaryomyces hansenii cell viability during the stationary phase. However, the mechanisms involved in these interactions remain unclear. It was also shown that yeast-bacterium interactions played a significant role in the establishment of this multispecies ecosystem on the cheese surface. Yeasts were key species in bacterial development, but their influences on the bacteria differed. It appeared that the growth of Arthrobacter arilaitensis or Hafnia alvei relied less on a specific yeast function because these species dominated the bacterial flora, regardless of which yeasts were present in the ecosystem. For other bacteria, such as Leucobacter sp. or Brevibacterium aurantiacum, growth relied on a specific yeast, i.e., G. candidum. Furthermore, B. aurantiacum, Corynebacterium casei, and Staphylococcus xylosus showed reduced colonization capacities in comparison with the other bacteria in this model cheese. Bacterium-bacterium interactions could not be clearly identified. 相似文献
110.