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Frederic Lorenzo - One of the best experts on this subject based on the ideXlab platform.
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polymorphisms and intronic structures in the 18s subunit ribosomal rna gene of the fungi Scytalidium dimidiatum and Scytalidium hyalinum
Fems Microbiology Letters, 2004Co-Authors: M Machouart, F Derouin, C Lacroix, Feuilhade M De Chauvin, Frederic LorenzoAbstract:The fungi Scytalidium dimidiatum (Nattrassia mangiferae synanamorph) and Scytalidium hyalinum are mainly encountered in (sub)tropical areas as plant pathogens and agents of human dermatomycosis. Because the classification and differentiation of these two species is unclear, we studied 22 S. dimidiatum and 15 S. hyalinum isolates in order to identify potential species-specific insertions and polymorphisms in the 18S subunit ribosomal gene. The presence of an IE intron in S. dimidiatum, together with a single polymorphism (A in S. dimidiatum, G in S. hyalinum) in the coding region, allowed us to differentiate these two species in most cases. Moreover, in one S. dimidiatum isolate we found a group IC1 intron containing a putative truncated His-Cys endonuclease gene. This enzyme shows strong similarity to the intronic homing endonuclease of Physarum polycephalum. Based on these results and our previous findings, we propose an evolutionary pathway for 18S rDNA S. dimidiatum insertions, implying independent events.
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nucleotide structure of the Scytalidium hyalinum and Scytalidium dimidiatum 18s subunit ribosomal rna gene evidence for the insertion of a group ie intron in the rdna gene of s dimidiatum
Fems Microbiology Letters, 2002Co-Authors: Marie Machouartdubach, Martine Feuilhade De Chauvin, C Lacroix, Christelle Vaury, Christine Bellanne, F Derouin, Frederic LorenzoAbstract:The molds Scytalidium dimidiatum (Nattrassia mangiferae synanamorph) and Scytalidium hyalinum are responsible for dermatomycosis in humans. We sequenced their 18S subunit ribosomal RNA gene to identify these species with molecular biology-based methods. The coding sequences differed by a single polymorphism (A in S. dimidiatum, G in S. hyalinum). Moreover, we found an insert at position 1199 in the 18S rRNA gene sequence of S. dimidiatum. Its potential secondary structure was characteristic of a group IE intron. Bioinformatic and phylogenic group IE intron analyses generated four main homogeneous clusters. The S. dimidiatum intron is original and not related with other known IE group introns.
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rapid discrimination among dermatophytes Scytalidium spp and other fungi with a pcr restriction fragment length polymorphism ribotyping method
Journal of Clinical Microbiology, 2001Co-Authors: Marie Machouartdubach, Claire Lacroix, Martine Feuilhade De Chauvin, Isabelle Le Gall, Catherine Giudicelli, Frederic Lorenzo, Francis DerouinAbstract:Dermatomycoses are very common infections caused mainly by dermatophytes. Scytalidiosis is a differential mycological diagnosis, especially in tropical and subtropical areas. Since a culture-based diagnosis takes 2 to 3 weeks, we set up a PCR-restriction fragment length polymorphism (RFLP) method for rapid discrimination of these fungi in clinical samples. The hypervariable V4 domain of the small ribosomal subunit 18S gene was chosen as the target for PCR. The corresponding sequences from 19 fungal species (9 dermatophytes, 2 Scytalidium species, 6 other filamentous fungi, and 2 yeasts) were obtained from databases or were determined in the laboratory. Sequences were aligned to design primers for dermatophyte-specific PCR and to identify digestion sites for RFLP analysis. The reliability of PCR-RFLP for the diagnosis of dermatomycosis was assessed on fungal cultures and on specimens from patients with suspected dermatomycosis. Two sets of primers preferentially amplified fungal DNA from dermatophytes (DH1L and DH1R) or from Scytalidium spp. (DH2L and DH1R) relative to DNA from bacteria, yeasts, some other filamentous fungi, and humans. Digestion of PCR products with EaeI or BamHI discriminated between dermatophytes and Scytalidium species, as shown with cultures of 31 different fungal species. When clinical samples were tested by PCR-RFLP, blindly to mycological findings, the results of the two methods agreed for 74 of 75 samples. Dermatophytes and Scytalidium spp. can thus be readily discriminated by PCR-RFLP within 24 h. This method can be applied to clinical samples and is suited to rapid etiologic diagnosis and treatment selection for patients with dermatomycosis.
Carbajal Alarcón, Frank Shamir - One of the best experts on this subject based on the ideXlab platform.
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Identificación de Hongos Endófitos y su uso en la bioprotección de plántulas de Café para reducir el daño de Colletotrichum coffeanum en San Martin - Perú
Universidad Nacional de San Martín, 2017Co-Authors: Carbajal Alarcón, Frank ShamirAbstract:Coffee being grown in tropical climates, with a relatively high humidity is prone to many diseases of fungal type, and production is greatly affected by them, was affected in the last times. The use of endophytic fungi (Trichoderma sp, Asperllus sp, Verticilium sp) could be an alternative to solve these problems, with the objective of determining the influence of the best bioprotective isolates against Colletotrichum coffeanum. it was possible to identify eight endophyte fungi: Thichoderma sp, Aspergillus sp, Verticilium sp, Thielaviopsis sp, Scytalidium sp, Xylaria sp, Nigrospora sp and Pestalotiopsis sp in the dual test, the endophyte fungus Aspergilius sp, had the fastest growth and development linear of the colony, being that at 6 days (6th evaluation) reached its maximum development with 9 cm and at 4 days with a growth of 7.28 cm could control the growth and linear development of Colletotrichum sp colony that reached 1.66 cm. followed Trichoderma sp, reaching its maximum growth from 9 cm to 9th day (9th evaluation) and that with growth of 7,14 cm to the 5th day (5th evaluation) was able to control the growth and linear development of Colletotrichum sp colony that only reached 1, 82 cm. in the endophytic capacity, the plants inoculated with Trichoderma sp, Aspegillus sp and Verticilium sp had better effect obtaining greater number of leaves per plant, the size of the plants, Vigor of the leaves in addition did not present symptoms of disease, in contrast the plants inoculated with Thielaviopsis sp, Scytalidium sp, Xylaria sp, Nigrospora sp, Pestalotiopsis sp presented small leaves with chlorosis, with symptoms of stress and diseaseEl café en el Perú, es el único producto agrícola de exportación tradicional, se exporta a diferentes países del mundo, en los últimos años la producción se ha visto afectada, por la roya amarilla, el ojo de pollo, arañero del cafeto, así como estas existen otras enfermedades como la antracnosis que últimamente están teniendo importancia. El uso de hongos endófitos (Trichoderma sp Aspergillus sp, Verticilium sp) es una alternativa para dar solución a estos problemas, con el objetivo de determinar la influencia de los mejores aislamientos bioprotectores frente a Colletotrichum coffeanum. Se lograron identificar ocho hongos endófitos: Trichoderma sp, Aspergillus sp, Verticilium sp, Thielaviopsis sp, Scytalidium sp, Xylaria sp, Nigrospora sp y Pestalotiopsis sp. En la prueba dual, el hongo endófito Aspergillus sp, tuvo el más rápido crecimiento, con 7,28 cm a los cuatro días, y desarrollo lineal de la colonia con 9 cm a los seis días, seguido por Trichoderma sp, con 7,14 cm al quinto día en la prueba dual, y 9 cm al 9no día en el desarrollo lineal. En la capacidad endofítica, las plantas inoculadas con Trichoderma sp, Aspergillus sp y Verticilium sp tuvieron mejor efecto obteniendo mayor número de hojas por planta, el tamaño de las plantas, vigor de las hojas además no presentaron síntomas de enfermedad, en cambio las plantas inoculadas con Thielaviopsis sp, Scytalidium sp, Xylaria sp, Nigrospora sp, Pestalotiopsis sp presentaron hojas pequeñas con clorosis, con síntomas de estrés y enfermedadTesi
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Identificación de Hongos Endófitos y su uso en la bioprotección de plántulas de Café para reducir el daño de Colletotrichum coffeanum en San Martin - Perú
Universidad Nacional de San Martin, 2016Co-Authors: Carbajal Alarcón, Frank ShamirAbstract:El café en el Perú, es el único producto agrícola de exportación tradicional, se exporta a diferentes países del mundo, en los últimos años la producción se ha visto afectada, por la roya amarilla, el ojo de pollo, arañero del cafeto, así como estas existen otras enfermedades como la antracnosis que últimamente están teniendo importancia. El uso de hongos endófitos (Trichoderma sp Aspergillus sp, Verticilium sp) es una alternativa para dar solución a estos problemas, con el objetivo de determinar la influencia de los mejores aislamientos bioprotectores frente a Colletotrichum coffeanum. Se lograron identificar ocho hongos endófitos: Trichoderma sp, Aspergillus sp, Verticilium sp, Thielaviopsis sp, Scytalidium sp, Xylaria sp, Nigrospora sp y Pestalotiopsis sp. En la prueba dual, el hongo endófito Aspergillus sp, tuvo el más rápido crecimiento, con 7,28 cm a los cuatro días, y desarrollo lineal de la colonia con 9 cm a los seis días, seguido por Trichoderma sp, con 7,14 cm al quinto día en la prueba dual, y 9 cm al 9no día en el desarrollo lineal. En la capacidad endofítica, las plantas inoculadas con Trichoderma sp, Aspergillus sp y Verticilium sp tuvieron mejor efecto obteniendo mayor número de hojas por planta, el tamaño de las plantas, vigor de las hojas además no presentaron síntomas de enfermedad, en cambio las plantas inoculadas con Thielaviopsis sp, Scytalidium sp, Xylaria sp, Nigrospora sp, Pestalotiopsis sp presentaron hojas pequeñas con clorosis, con síntomas de estrés y enfermedadTesisCoffee being grown in tropical climates, with a relatively high humidity is prone to many diseases of fungal type, and production is greatly affected by them, was affected in the last times. The use of endophytic fungi (Trichoderma sp, Asperllus sp, Verticilium sp) could be an alternative to solve these problems, with the objective of determining the influence of the best bioprotective isolates against Colletotrichum coffeanum. it was possible to identify eight endophyte fungi: Thichoderma sp, Aspergillus sp, Verticilium sp, Thielaviopsis sp, Scytalidium sp, Xylaria sp, Nigrospora sp and Pestalotiopsis sp in the dual test, the endophyte fungus Aspergilius sp, had the fastest growth and development linear of the colony, being that at 6 days (6th evaluation) reached its maximum development with 9 cm and at 4 days with a growth of 7.28 cm could control the growth and linear development of Colletotrichum sp colony that reached 1.66 cm. followed Trichoderma sp, reaching its maximum growth from 9 cm to 9th day (9th evaluation) and that with growth of 7,14 cm to the 5th day (5th evaluation) was able to control the growth and linear development of Colletotrichum sp colony that only reached 1, 82 cm. in the endophytic capacity, the plants inoculated with Trichoderma sp, Aspegillus sp and Verticilium sp had better effect obtaining greater number of leaves per plant, the size of the plants, Vigor of the leaves in addition did not present symptoms of disease, in contrast the plants inoculated with Thielaviopsis sp, Scytalidium sp, Xylaria sp, Nigrospora sp, Pestalotiopsis sp presented small leaves with chlorosis, with symptoms of stress and diseas
Edward I. Solomon - One of the best experts on this subject based on the ideXlab platform.
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a study of a series of recombinant fungal laccases and bilirubin oxidase that exhibit significant differences in redox potential substrate specificity and stability
Biochimica et Biophysica Acta, 1996Co-Authors: Feng Xu, Jill Angela Wahleithner, Uma M Sundaram, Woonsup Shin, Stephen H. Brown, Edward I. SolomonAbstract:A series of fungal laccases (Polyporus pinsitus, Rhizoctonia solani, Myceliophthora hermophila, Scytalidium thermophilum) and one bilirubin oxidase (Myrothecium verrucaria) have been studied to determine their redox potential, specificity, and stability. Polyporus and Rhizoctonia laccases possess potentials near 0.7–0.8 V (vs. NHE), while other oxidases have potentials near 0.5 V. It is observed that higher redox potential correlates with higher activity. By EPR, no significant change in the geometry of type 1 copper (II) site is observed over this series. At the optimal pH, the two substrates studied, 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) and syringaldazine, show Km values ranging from 10 to 120 and from 1 to 45 μM; and kcat values ranging from 50 to 16000 and 200 to 3000 per min, respectively. The enzymes are more stable in the neutral-alkaline pH range. The thermal stability is in the order of bilirubin oxidase ≈ Myceliophthora laccase ≈ Scytalidium laccase > Polyporus laccase > Rhizoctonia laccase. Based on these results and the sequence alignments made against Zucchini ascorbate oxidase it is speculated that structural differences in the substrate-activation site (a ‘blue’, type 1 copper center) control the redox potential range as well as substrate specificity, and the cystine content contributes to stability.
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a study of a series of recombinant fungal laccases and bilirubin oxidase that exhibit significant differences in redox potential substrate specificity and stability
Biochimica et Biophysica Acta, 1996Co-Authors: Woonsup Shin, Jill Angela Wahleithner, Uma M Sundaram, Stephen Brown, Edward I. SolomonAbstract:A series of fungal laccases (Polyporus pinsitus, Rhizoctonia solani, Myceliophthora thermophila, Scytalidium thermophilum) and one bilirubin oxidase (Myrothecium verrucaria) have been studied to determine their redox potential, specificity, and stability. Polyporus and Rhizoctonia laccases possess potentials near 0.7-0.8 V (vs. NHE), while other oxidases have potentials near 0.5 V. It is observed that higher redox potential correlates with higher activity. By EPR, no significant change in the geometry of type 1 copper (II) site is observed over this series. At the optimal pH, the two substrates studied, 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) and syringaldazine, show Km values ranging form 10 to 120 and from 1 to 45 microM; and kcat values ranging from 50 to 16 000 and 200 to 3000 per min, respectively. The enzymes are more stable in the neutral-alkaline pH range. The thermal stability is in the order of bilirubin oxidase equivalent to Myceliophthora laccase equivalent to Scytalidium laccase > Polyporus laccase > Rhizoctonia laccase. Based on these results and the sequence alignments made against Zucchini ascorbate oxidase it is speculated that structural differences in the substrate-activation site (a 'blue', type 1 copper center) control the redox potential range as well as substrate specificity, and the cystine content contributes to stability.
Marie Machouartdubach - One of the best experts on this subject based on the ideXlab platform.
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nucleotide structure of the Scytalidium hyalinum and Scytalidium dimidiatum 18s subunit ribosomal rna gene evidence for the insertion of a group ie intron in the rdna gene of s dimidiatum
Fems Microbiology Letters, 2002Co-Authors: Marie Machouartdubach, Martine Feuilhade De Chauvin, C Lacroix, Christelle Vaury, Christine Bellanne, F Derouin, Frederic LorenzoAbstract:The molds Scytalidium dimidiatum (Nattrassia mangiferae synanamorph) and Scytalidium hyalinum are responsible for dermatomycosis in humans. We sequenced their 18S subunit ribosomal RNA gene to identify these species with molecular biology-based methods. The coding sequences differed by a single polymorphism (A in S. dimidiatum, G in S. hyalinum). Moreover, we found an insert at position 1199 in the 18S rRNA gene sequence of S. dimidiatum. Its potential secondary structure was characteristic of a group IE intron. Bioinformatic and phylogenic group IE intron analyses generated four main homogeneous clusters. The S. dimidiatum intron is original and not related with other known IE group introns.
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rapid discrimination among dermatophytes Scytalidium spp and other fungi with a pcr restriction fragment length polymorphism ribotyping method
Journal of Clinical Microbiology, 2001Co-Authors: Marie Machouartdubach, Claire Lacroix, Martine Feuilhade De Chauvin, Isabelle Le Gall, Catherine Giudicelli, Frederic Lorenzo, Francis DerouinAbstract:Dermatomycoses are very common infections caused mainly by dermatophytes. Scytalidiosis is a differential mycological diagnosis, especially in tropical and subtropical areas. Since a culture-based diagnosis takes 2 to 3 weeks, we set up a PCR-restriction fragment length polymorphism (RFLP) method for rapid discrimination of these fungi in clinical samples. The hypervariable V4 domain of the small ribosomal subunit 18S gene was chosen as the target for PCR. The corresponding sequences from 19 fungal species (9 dermatophytes, 2 Scytalidium species, 6 other filamentous fungi, and 2 yeasts) were obtained from databases or were determined in the laboratory. Sequences were aligned to design primers for dermatophyte-specific PCR and to identify digestion sites for RFLP analysis. The reliability of PCR-RFLP for the diagnosis of dermatomycosis was assessed on fungal cultures and on specimens from patients with suspected dermatomycosis. Two sets of primers preferentially amplified fungal DNA from dermatophytes (DH1L and DH1R) or from Scytalidium spp. (DH2L and DH1R) relative to DNA from bacteria, yeasts, some other filamentous fungi, and humans. Digestion of PCR products with EaeI or BamHI discriminated between dermatophytes and Scytalidium species, as shown with cultures of 31 different fungal species. When clinical samples were tested by PCR-RFLP, blindly to mycological findings, the results of the two methods agreed for 74 of 75 samples. Dermatophytes and Scytalidium spp. can thus be readily discriminated by PCR-RFLP within 24 h. This method can be applied to clinical samples and is suited to rapid etiologic diagnosis and treatment selection for patients with dermatomycosis.
Woonsup Shin - One of the best experts on this subject based on the ideXlab platform.
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a study of a series of recombinant fungal laccases and bilirubin oxidase that exhibit significant differences in redox potential substrate specificity and stability
Biochimica et Biophysica Acta, 1996Co-Authors: Feng Xu, Jill Angela Wahleithner, Uma M Sundaram, Woonsup Shin, Stephen H. Brown, Edward I. SolomonAbstract:A series of fungal laccases (Polyporus pinsitus, Rhizoctonia solani, Myceliophthora hermophila, Scytalidium thermophilum) and one bilirubin oxidase (Myrothecium verrucaria) have been studied to determine their redox potential, specificity, and stability. Polyporus and Rhizoctonia laccases possess potentials near 0.7–0.8 V (vs. NHE), while other oxidases have potentials near 0.5 V. It is observed that higher redox potential correlates with higher activity. By EPR, no significant change in the geometry of type 1 copper (II) site is observed over this series. At the optimal pH, the two substrates studied, 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) and syringaldazine, show Km values ranging from 10 to 120 and from 1 to 45 μM; and kcat values ranging from 50 to 16000 and 200 to 3000 per min, respectively. The enzymes are more stable in the neutral-alkaline pH range. The thermal stability is in the order of bilirubin oxidase ≈ Myceliophthora laccase ≈ Scytalidium laccase > Polyporus laccase > Rhizoctonia laccase. Based on these results and the sequence alignments made against Zucchini ascorbate oxidase it is speculated that structural differences in the substrate-activation site (a ‘blue’, type 1 copper center) control the redox potential range as well as substrate specificity, and the cystine content contributes to stability.
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a study of a series of recombinant fungal laccases and bilirubin oxidase that exhibit significant differences in redox potential substrate specificity and stability
Biochimica et Biophysica Acta, 1996Co-Authors: Woonsup Shin, Jill Angela Wahleithner, Uma M Sundaram, Stephen Brown, Edward I. SolomonAbstract:A series of fungal laccases (Polyporus pinsitus, Rhizoctonia solani, Myceliophthora thermophila, Scytalidium thermophilum) and one bilirubin oxidase (Myrothecium verrucaria) have been studied to determine their redox potential, specificity, and stability. Polyporus and Rhizoctonia laccases possess potentials near 0.7-0.8 V (vs. NHE), while other oxidases have potentials near 0.5 V. It is observed that higher redox potential correlates with higher activity. By EPR, no significant change in the geometry of type 1 copper (II) site is observed over this series. At the optimal pH, the two substrates studied, 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) and syringaldazine, show Km values ranging form 10 to 120 and from 1 to 45 microM; and kcat values ranging from 50 to 16 000 and 200 to 3000 per min, respectively. The enzymes are more stable in the neutral-alkaline pH range. The thermal stability is in the order of bilirubin oxidase equivalent to Myceliophthora laccase equivalent to Scytalidium laccase > Polyporus laccase > Rhizoctonia laccase. Based on these results and the sequence alignments made against Zucchini ascorbate oxidase it is speculated that structural differences in the substrate-activation site (a 'blue', type 1 copper center) control the redox potential range as well as substrate specificity, and the cystine content contributes to stability.
