Cyphellophora is a genus of black yeast-like fungi characterised by having simple phialides with multiseptate,curved conidia.Judging from SSU and LSU data,Cyphellophora was found to be located in a well-supported clad...Cyphellophora is a genus of black yeast-like fungi characterised by having simple phialides with multiseptate,curved conidia.Judging from SSU and LSU data,Cyphellophora was found to be located in a well-supported clade within the Chaetothyriales comprising a number of species occurring on human skin and nail.Cyphellophora is phylogenetically close to Phialophora europaea,P.reptans and P.oxyspora,though morphologically these species produce singlecelled phialoconidia rather than multiseptate ones.Pseudomicrodochium suttonii and P.fusarioides have dark colonies and phylogenetically fit in with Cyphellophora;the type species of Pseudomicrodochium,P.aciculare,has similar,septate conidia but has a hyaline thallus.In the present study,multilocus phylogenetic analyses were combined with morphology and physiology.Sequences of the internal transcribed spacer region,the DNA dependent RNA polymerase II largest subunit and the partial beta tubulin gene were analysed for a set of 30 strains.Two novel species,Cyphellophora pauciseptata and Phialophora ambigua were discovered.Cyphellophora eucalypti was reduced to synonymy of C.guyanensis.The role of the studied fungi between colonization and infection of human skin was discussed.Putative virulence factors for these black yeast-like fungi were hypothesized to be the ability to assimilate monoaromatic hydrocarbons,to produce melanin pigments,and to tolerate the temperature of epidermal human skin.展开更多
Ants in the tribe Attini(Hymenoptera,Formicidae)maintain a 50 million-year-old lifestyle of co-evolution with symbiotic basidiomycetous fungi which they cultivate as essential source of nutrition.However,other microor...Ants in the tribe Attini(Hymenoptera,Formicidae)maintain a 50 million-year-old lifestyle of co-evolution with symbiotic basidiomycetous fungi which they cultivate as essential source of nutrition.However,other microorganisms have been reported from ant habitats indicating a higher diversity of consistently associated species than established to date.Recently,black yeast-like fungi have been reported as a possible symbiont,like a competitor of the actinomycete bacteria that grow in the integument of the insects.During the mating season,gynes of Atta capiguara and A.laevigata were collected from nests located in Botucatu,SP,Brazil and sampled using flotation technique.Phylogenetic analysis based on ITS,partial 28S(LSU)andβ-tubulin sequences revealed the occurrence of two novel species of Phialophora among the melanized fungi isolated.展开更多
[Objective] This study aimed to isolate an acidophilic fungus and analyze the acidophilic enzymes secreted by this fungus. [Method] A heterotrophic fungus was isolated from the leaching solution of a uranium ore in Ji...[Objective] This study aimed to isolate an acidophilic fungus and analyze the acidophilic enzymes secreted by this fungus. [Method] A heterotrophic fungus was isolated from the leaching solution of a uranium ore in Jiangxi Province using oligotrophic acid selective medium (pH 2.5), and was named RBS-6. This strain was then identified according to its colony morphology and molecular indicator rDNA-ITS. Finally, the glycoside hydrolases secreted by RBS-6 were analyzed. [Result] This fungus RBS-6 was acidophilic, and grew best at pH4.0. Its rDNA-ITS sequence shared the highest homology (98%) with that of Phialophora sp. CGMCC 3329 (GU 082377). So it was identified as a fungus of Phialophora sp., and was temporarily named as Phialophora sp. RBS-6. It can produce six glycoside hydrolases, in cluding α-galactosidase glucosidase, β-glucosidase, β-mannanase and β-glucanase. All the enzymes were acidophilic, for which the optimum reaction pH was 3.0-4.0. Among them, β-glucanase exhibited the highest activity at pH 3.5 and 50 ℃; in addition, it was heat-stable as 58% of the enzyme activity was remained after incubation at 50 ℃ for 60 min. [Conclusion] The isolated fungus which was identified as an acidophilic member of Phialophora sp., was a new strain producing acidophilic enzymes. This study supplied new data for the research on Phialophora fungi.展开更多
基金This work was supported by the project 11CPD009 of the china desk of the Netherlands Academy of Sciences.
文摘Cyphellophora is a genus of black yeast-like fungi characterised by having simple phialides with multiseptate,curved conidia.Judging from SSU and LSU data,Cyphellophora was found to be located in a well-supported clade within the Chaetothyriales comprising a number of species occurring on human skin and nail.Cyphellophora is phylogenetically close to Phialophora europaea,P.reptans and P.oxyspora,though morphologically these species produce singlecelled phialoconidia rather than multiseptate ones.Pseudomicrodochium suttonii and P.fusarioides have dark colonies and phylogenetically fit in with Cyphellophora;the type species of Pseudomicrodochium,P.aciculare,has similar,septate conidia but has a hyaline thallus.In the present study,multilocus phylogenetic analyses were combined with morphology and physiology.Sequences of the internal transcribed spacer region,the DNA dependent RNA polymerase II largest subunit and the partial beta tubulin gene were analysed for a set of 30 strains.Two novel species,Cyphellophora pauciseptata and Phialophora ambigua were discovered.Cyphellophora eucalypti was reduced to synonymy of C.guyanensis.The role of the studied fungi between colonization and infection of human skin was discussed.Putative virulence factors for these black yeast-like fungi were hypothesized to be the ability to assimilate monoaromatic hydrocarbons,to produce melanin pigments,and to tolerate the temperature of epidermal human skin.
基金The authors would like to thank D.Smith and G.Omer for technical support with DNA purification,PCR and sequencing.Laboratory work at the CBS was financed by the Royal Dutch Academy of Arts and Science(KNAW)the Fonds voor Economische Stuctuurversterking(FES)with the grant‘Barcoding the CBS collections’.Laboratory work at UNESP was financed by CNPq(proc.305.457/2001-0 and 560.682/2010-7).
文摘Ants in the tribe Attini(Hymenoptera,Formicidae)maintain a 50 million-year-old lifestyle of co-evolution with symbiotic basidiomycetous fungi which they cultivate as essential source of nutrition.However,other microorganisms have been reported from ant habitats indicating a higher diversity of consistently associated species than established to date.Recently,black yeast-like fungi have been reported as a possible symbiont,like a competitor of the actinomycete bacteria that grow in the integument of the insects.During the mating season,gynes of Atta capiguara and A.laevigata were collected from nests located in Botucatu,SP,Brazil and sampled using flotation technique.Phylogenetic analysis based on ITS,partial 28S(LSU)andβ-tubulin sequences revealed the occurrence of two novel species of Phialophora among the melanized fungi isolated.
基金Supported by Manufacture - Learning - Research Cooperation Project of Education Department of Jiangxi Province(GJJ09008)Nuclear Power Development Projects [COSTIND, (2009)1230]~~
文摘[Objective] This study aimed to isolate an acidophilic fungus and analyze the acidophilic enzymes secreted by this fungus. [Method] A heterotrophic fungus was isolated from the leaching solution of a uranium ore in Jiangxi Province using oligotrophic acid selective medium (pH 2.5), and was named RBS-6. This strain was then identified according to its colony morphology and molecular indicator rDNA-ITS. Finally, the glycoside hydrolases secreted by RBS-6 were analyzed. [Result] This fungus RBS-6 was acidophilic, and grew best at pH4.0. Its rDNA-ITS sequence shared the highest homology (98%) with that of Phialophora sp. CGMCC 3329 (GU 082377). So it was identified as a fungus of Phialophora sp., and was temporarily named as Phialophora sp. RBS-6. It can produce six glycoside hydrolases, in cluding α-galactosidase glucosidase, β-glucosidase, β-mannanase and β-glucanase. All the enzymes were acidophilic, for which the optimum reaction pH was 3.0-4.0. Among them, β-glucanase exhibited the highest activity at pH 3.5 and 50 ℃; in addition, it was heat-stable as 58% of the enzyme activity was remained after incubation at 50 ℃ for 60 min. [Conclusion] The isolated fungus which was identified as an acidophilic member of Phialophora sp., was a new strain producing acidophilic enzymes. This study supplied new data for the research on Phialophora fungi.