The cometabolic roles of glucose were investigated in decolorization of an azo dye, Reactive Black 5, by yeast isolates, Debaryomyces polymorphus and Candida tropicalis. The results indicated that the dye degradation ...The cometabolic roles of glucose were investigated in decolorization of an azo dye, Reactive Black 5, by yeast isolates, Debaryomyces polymorphus and Candida tropicalis. The results indicated that the dye degradation by the two yeasts was highly associated with the yeast growth process and glucose presence in the medium. Color removal of 200 mg dye/L was increased from 76.4% to 92.7% within 60 h to 100% within 18-24 h with the increase of glucose from 5 to 10 g/L, although the activity of manganese dependent peroxidase （MnP） decreased by 2-8 times in this case. Hydrogen peroxide of 233.3 μg/L was detected in 6 h in D. polymorphus culture. The cometabolic functions of glucose and hydrogen peroxide could be also confirmed by the further color removals of 95.8% or 78,9% in the second cycle of decolorization tests in which 7 g glucose/L or 250 μg H202/L was superadded respectively together with 200 mg dye/L.展开更多
Extremely acidic soils(pH<3)harbour mycobiota that are different from less acidic habitats and are dominated by a small number of fungal species.During investigation of the mycobiota of highly acidic soils in the C...Extremely acidic soils(pH<3)harbour mycobiota that are different from less acidic habitats and are dominated by a small number of fungal species.During investigation of the mycobiota of highly acidic soils in the Czech Republic and Iceland,a group of melanised fungal isolates was obtained.Based on phenotype and nuclear ribosomal DNA sequences(ITS region,SSU,LSU),the isolates were accommodated by three phylogenetic lineages within the family Teratosphaeriaceae(Capnodiales,Dothideomycetes).The first lineage is here described as a new acidotolerant genus and species Acidiella bohemica gen.nov.et sp.nov.The most closely related species to this new clade are other extremotolerant fungi isolated from rocks and lichens collected in the Alps and Antarctica as well as leaf-spotting species and opportunistic human pathogens.The isolates belonging to the second and the third lineages were identified as the recently described acidophilic fungi Acidomyces acidophilus and Teratosphaeria acidotherma,respectively.The taxonomic status of both sister species is discussed and the latter species is ascribed here to the genus Acidomyces.展开更多
Exophiala is a genus comprising several species of opportunistic black yeasts,which belongs to Ascomycotina.It is a rare cause of fungal infections.However,infections are often chronic and recalcitrant,and while the n...Exophiala is a genus comprising several species of opportunistic black yeasts,which belongs to Ascomycotina.It is a rare cause of fungal infections.However,infections are often chronic and recalcitrant,and while the number of cases is steadily increasing in both immunocompromised and immunocompetent people,detailed knowledge remains scarce regarding infection mechanisms,virulence factors,specific predisposing factors,risk factors,and host response.The most common manifestations of Exophiala infection are skin infections,and the most frequent type of deep infection is pulmonary infection due to inhalation.The invasive disease ranges from cutaneous or subcutaneous infection to systemic dissemination to internal organs.The final identification of the causative organism should be achieved through a combination of several methods,including the newly introduced diagnostic analysis,matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry,together with sequencing of the ribosomal ribonucleic acid internal transcribed spacer region of the fungi,and histological and culture findings.Regarding treatment,because anti-infective agents and natural compounds exhibited poor antibiofilm activity,few treatments have ultimately been found to be effective for specific antifungal therapy,so the optimal antifungal therapy and duration of therapy for these infections remain unknown.Therefore,most forms of disease caused by Exophiala dermatitidis require aggressive combination therapies:Both surgical intervention and aggressive antifungal therapy with novel compounds and azoles are necessary for effective treatment.展开更多
Numerous agents of infections in humans and other mammals are found among fungi that are able to survive extreme environmental conditions and to quickly adapt to novel habitats.Nevertheless,the relationship between op...Numerous agents of infections in humans and other mammals are found among fungi that are able to survive extreme environmental conditions and to quickly adapt to novel habitats.Nevertheless,the relationship between opportunistic potential and polyextremotolerance was not yet studied systematically in fungi.Here,the link between polyextremotolerance and opportunistic pathogenicity is shown in a kingdom-wide phylogenetic analysis as a statistically significant co-occurrence of extremotolerance(e.g.osmotolerance and psychrotolerance)and opportunism at the level of fungal orders.In addition to extremotolerance,fungal opportunists share another characteristic—an apparent lack of specialised virulence traits.This is illustrated by a comparative genomic analysis of 20 dothideomycetous and eurotiomycetous black fungi.While the genomes of specialised fungal plant pathogens were significantly enriched in known virulence-associated genes that encode secreted proteases,carbohydrate active enzyme families,polyketide synthases,and non-ribosomal peptide synthetases,no such signatures were observed in human opportunists.Together the presented results have several implications.If infection of human hosts is a side effect of fungal stress tolerance and adaptability,the human body is most likely neither the preferred habitat of such species,nor important for their evolutionary success.This defines opportunism as opposed to pathogenicity,where infection is advantageous for the species’fitness.Since opportunists are generally incapable of the host-to-host transmission,any host-specific adaptations are likely to be lost with the resolution of the infection,explaining the observed lack of specialised virulence traits.In this scenario opportunistic infections should be seen as an evolutionary dead end and unlikely to lead to true pathogenicity.展开更多
本试验旨在研究营养水平和酵母硒对烟台黑猪生长性能、养分表观消化率及血清抗氧化指标的影响。选取体况良好、体重(70.30±1.30)kg的烟台黑猪48头,随机分为4个组,每组4个重复,每个重复3头猪。Ⅰ组饲喂低营养水平饲粮(消化能水平11....本试验旨在研究营养水平和酵母硒对烟台黑猪生长性能、养分表观消化率及血清抗氧化指标的影响。选取体况良好、体重(70.30±1.30)kg的烟台黑猪48头,随机分为4个组,每组4个重复,每个重复3头猪。Ⅰ组饲喂低营养水平饲粮(消化能水平11.19 M J/kg、粗蛋白质水平12.28%),Ⅱ组饲喂低营养水平饲粮+0.5 mg/kg酵母硒,Ⅲ组饲喂高营养水平饲粮(消化能水平13.11 M J/kg、粗蛋白质水平14.73%),Ⅳ组饲喂高营养水平饲粮+0.5 mg/kg酵母硒。预试期为7 d,正试期为105 d。结果表明:1)Ⅲ、Ⅳ组平均日增重(ADG)极显著高于Ⅰ、Ⅱ组(P<0.01),Ⅳ组平均日采食量(ADFI)极显著高于Ⅰ、Ⅱ组(P<0.01),Ⅳ组料重比(F/G)分别比Ⅰ、Ⅱ组降低了4.60%、5.74%(P<0.01)。2)Ⅳ组粗蛋白质表观消化率分别比Ⅰ、Ⅱ组提高了2.73%、3.17%(P<0.01),比Ⅲ组提高了0.82%(P>0.05)。3)Ⅱ、Ⅳ组血清超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性及总抗氧化能力(T-AOC)极显著高于Ⅰ、Ⅲ组(P<0.01),血清丙二醛(MDA)含量极显著低于Ⅰ、Ⅲ组(P<0.01)。4)对于生长性能、养分表观消化率和血清抗氧化指标,酵母硒与营养水平之间均没有互作效应(P>0.05)。由此可见,在本试验条件下,营养水平对烟台黑猪生长性能、粗蛋白质表观消化率有极显著影响,酵母硒能够极显著提高烟台黑猪抗氧化能力。展开更多
基金This work was supported by the Program for New Century Excellent Talents in University in China(No.NCET-05-0612)the National Natural Science Foundation of China(No.20677014).
文摘The cometabolic roles of glucose were investigated in decolorization of an azo dye, Reactive Black 5, by yeast isolates, Debaryomyces polymorphus and Candida tropicalis. The results indicated that the dye degradation by the two yeasts was highly associated with the yeast growth process and glucose presence in the medium. Color removal of 200 mg dye/L was increased from 76.4% to 92.7% within 60 h to 100% within 18-24 h with the increase of glucose from 5 to 10 g/L, although the activity of manganese dependent peroxidase （MnP） decreased by 2-8 times in this case. Hydrogen peroxide of 233.3 μg/L was detected in 6 h in D. polymorphus culture. The cometabolic functions of glucose and hydrogen peroxide could be also confirmed by the further color removals of 95.8% or 78,9% in the second cycle of decolorization tests in which 7 g glucose/L or 250 μg H202/L was superadded respectively together with 200 mg dye/L.
基金supported by the Grant Agency of the Charles University in Prague(project No.63009)by Czech Institutional Research Concept(No.AV0Z5020903)+1 种基金Ministry of Education of the Czech Republic(project No.MSM0021620828)Ministry of Agriculture(project No.MZE0002700604).
文摘Extremely acidic soils(pH<3)harbour mycobiota that are different from less acidic habitats and are dominated by a small number of fungal species.During investigation of the mycobiota of highly acidic soils in the Czech Republic and Iceland,a group of melanised fungal isolates was obtained.Based on phenotype and nuclear ribosomal DNA sequences(ITS region,SSU,LSU),the isolates were accommodated by three phylogenetic lineages within the family Teratosphaeriaceae(Capnodiales,Dothideomycetes).The first lineage is here described as a new acidotolerant genus and species Acidiella bohemica gen.nov.et sp.nov.The most closely related species to this new clade are other extremotolerant fungi isolated from rocks and lichens collected in the Alps and Antarctica as well as leaf-spotting species and opportunistic human pathogens.The isolates belonging to the second and the third lineages were identified as the recently described acidophilic fungi Acidomyces acidophilus and Teratosphaeria acidotherma,respectively.The taxonomic status of both sister species is discussed and the latter species is ascribed here to the genus Acidomyces.
文摘Exophiala is a genus comprising several species of opportunistic black yeasts,which belongs to Ascomycotina.It is a rare cause of fungal infections.However,infections are often chronic and recalcitrant,and while the number of cases is steadily increasing in both immunocompromised and immunocompetent people,detailed knowledge remains scarce regarding infection mechanisms,virulence factors,specific predisposing factors,risk factors,and host response.The most common manifestations of Exophiala infection are skin infections,and the most frequent type of deep infection is pulmonary infection due to inhalation.The invasive disease ranges from cutaneous or subcutaneous infection to systemic dissemination to internal organs.The final identification of the causative organism should be achieved through a combination of several methods,including the newly introduced diagnostic analysis,matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry,together with sequencing of the ribosomal ribonucleic acid internal transcribed spacer region of the fungi,and histological and culture findings.Regarding treatment,because anti-infective agents and natural compounds exhibited poor antibiofilm activity,few treatments have ultimately been found to be effective for specific antifungal therapy,so the optimal antifungal therapy and duration of therapy for these infections remain unknown.Therefore,most forms of disease caused by Exophiala dermatitidis require aggressive combination therapies:Both surgical intervention and aggressive antifungal therapy with novel compounds and azoles are necessary for effective treatment.
文摘Numerous agents of infections in humans and other mammals are found among fungi that are able to survive extreme environmental conditions and to quickly adapt to novel habitats.Nevertheless,the relationship between opportunistic potential and polyextremotolerance was not yet studied systematically in fungi.Here,the link between polyextremotolerance and opportunistic pathogenicity is shown in a kingdom-wide phylogenetic analysis as a statistically significant co-occurrence of extremotolerance(e.g.osmotolerance and psychrotolerance)and opportunism at the level of fungal orders.In addition to extremotolerance,fungal opportunists share another characteristic—an apparent lack of specialised virulence traits.This is illustrated by a comparative genomic analysis of 20 dothideomycetous and eurotiomycetous black fungi.While the genomes of specialised fungal plant pathogens were significantly enriched in known virulence-associated genes that encode secreted proteases,carbohydrate active enzyme families,polyketide synthases,and non-ribosomal peptide synthetases,no such signatures were observed in human opportunists.Together the presented results have several implications.If infection of human hosts is a side effect of fungal stress tolerance and adaptability,the human body is most likely neither the preferred habitat of such species,nor important for their evolutionary success.This defines opportunism as opposed to pathogenicity,where infection is advantageous for the species’fitness.Since opportunists are generally incapable of the host-to-host transmission,any host-specific adaptations are likely to be lost with the resolution of the infection,explaining the observed lack of specialised virulence traits.In this scenario opportunistic infections should be seen as an evolutionary dead end and unlikely to lead to true pathogenicity.
文摘本试验旨在研究营养水平和酵母硒对烟台黑猪生长性能、养分表观消化率及血清抗氧化指标的影响。选取体况良好、体重(70.30±1.30)kg的烟台黑猪48头,随机分为4个组,每组4个重复,每个重复3头猪。Ⅰ组饲喂低营养水平饲粮(消化能水平11.19 M J/kg、粗蛋白质水平12.28%),Ⅱ组饲喂低营养水平饲粮+0.5 mg/kg酵母硒,Ⅲ组饲喂高营养水平饲粮(消化能水平13.11 M J/kg、粗蛋白质水平14.73%),Ⅳ组饲喂高营养水平饲粮+0.5 mg/kg酵母硒。预试期为7 d,正试期为105 d。结果表明:1)Ⅲ、Ⅳ组平均日增重(ADG)极显著高于Ⅰ、Ⅱ组(P<0.01),Ⅳ组平均日采食量(ADFI)极显著高于Ⅰ、Ⅱ组(P<0.01),Ⅳ组料重比(F/G)分别比Ⅰ、Ⅱ组降低了4.60%、5.74%(P<0.01)。2)Ⅳ组粗蛋白质表观消化率分别比Ⅰ、Ⅱ组提高了2.73%、3.17%(P<0.01),比Ⅲ组提高了0.82%(P>0.05)。3)Ⅱ、Ⅳ组血清超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性及总抗氧化能力(T-AOC)极显著高于Ⅰ、Ⅲ组(P<0.01),血清丙二醛(MDA)含量极显著低于Ⅰ、Ⅲ组(P<0.01)。4)对于生长性能、养分表观消化率和血清抗氧化指标,酵母硒与营养水平之间均没有互作效应(P>0.05)。由此可见,在本试验条件下,营养水平对烟台黑猪生长性能、粗蛋白质表观消化率有极显著影响,酵母硒能够极显著提高烟台黑猪抗氧化能力。
文摘【目的】确定辐射污染土样中分离筛选获得的一批黑色酵母状真菌的分类学地位和抗逆特性。【方法】通过菌落形态和菌丝特征观察,结合LSU rDNA D1/D2区序列的系统发育分析,并进行了菌株的60Coγ射线照射、紫外线照射和对等重金属离子以及NaCl生长压力实验。【结果】上述菌株均为Aureobasidium属菌,其中菌株F99和F134均与A.pullulans var.subglaciale CBS 123388T具有最大同源性,为100%;菌株F19与A.pullulans var.melaogenum CBS 105.22T具有最大同源性,为99.8%;上述菌株均具有极强的抗逆特性。【结论】为了解耐辐射真菌抗逆机理提供了重要的研究材料。
