Ecologia de Paracoccidioides brasiliensis e Paracoccidioides lutzii e sua associação com o tatu Dasypus novemcinctus nos estados de São Paulo e Mato Grosso, Brasil.
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2018-03-01
Autores
Hrycyk, Marluce Francisca
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Universidade Estadual Paulista (Unesp)
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Paracoccidioides spp. são fungos que vivem no ambiente (solo) e em associação com tecidos de hospedeiros mamíferos. Apresentam como característica de patogenicidade o termo-dimorfismo, em que, a 25º C apresenta a fase micelial e produz suas partículas infectantes (conídios) e a 35-37º C está sob forma de leveduras (forma parasitária). As características morfológicas e micromorfológicas são importantes, mas insuficientes para a diferenciação entre os genótipos. Contudo, o avanço no conhecimento da Biologia Molecular nos últimos anos permitiu uma grande compreensão da biologia e das relações filogenéticas de Paracoccidioides spp. A região de ITS1-5.8S-ITS2 (rDNA) tem sido largamente usada na identificação de diversos fungos, sendo muito útil para discriminar entre P. brasiliensis e P. lutzii, no entanto, ela não separa entre as genótipos do complexo P. brasiliensis (S1, PS2, PS3 e PS4), no qual, recentemente foi proposto um rearranjo taxonômico, em que foram descritas como novas espécies de Paracoccidioides: P. brasiliensis para S1, P. americana para PS2, P. restrepiensis para PS3 e P. venezuelensis para PS4. Além do seqüenciamento do ITS, é necessário incluir outras regiões gênicas mais ou menos polimórficas para estudos filogenéticos que visam identificar Paracoccidioides spp. como nesse estudo. Este trabalho teve como objetivo mapear áreas de ocorrência e isolar Paracoccidioides a partir de tatus (Dasypus novemcinctus), bem com detectar molecularmente por Nested-PCR o DNA do fungo em amostras de solo e nos órgãos (baço, fígado e linfonodos mesentéricos) de tatus. Nós isolamos o fungo de tatus do Sudeste (Botucatu/SP) e Centro-Oeste (Alta Floresta/MT). Todos os isolados foram caracterizados molecularmente pelo seqüenciamento ITS-rDNA e gp43 exon 2 e por PCR-RFLP de alfa tubulina (tub1) como P. brasiliensis e P. americana. A reação de Nested-PCR foi sensível e permitiu detectar o DNA de Paracoccidioides nas amostras de tecido (baço, fígado e linfonodos mesentéricos) de D. novemcinctus e também no solo dos Estados de São Paulo e Mato Grosso. A construção filogenética com os amplicons ambientais de solo mostrou que P. lutzii está amplamente presente nessas regiões (Sudeste e Centro-Oeste), além do que, amplicons de P. lutzii de Alta Floresta/MT clusterizaram em um clado separadamente, sugerindo que espécies crípticas podem existir, dentro de P. lutzii.
Paracoccidioides spp. are fungi that live in the environment (soil) and in association with tissues of mammalian hosts. They present as a characteristic of pathogenicity the thermo - dimorphism, in which, at 25º C it presents the m ycelial phase and produces its infective particles (conidia) and at 35 - 37º C it is in the form of yeasts (parasitic form). The morphological and micromorphological characteristics are important, but insufficient for the differentiation between the genotype s. However, the advance in the knowledge of Molecular Biology in recent years has allowed a great understanding of the biology and phylogenetic relationships of Paracoccidioides spp. The region of ITS1 - 5.8S - ITS2 (rDNA) has been widely used in the identific ation of several fungi, in which it is very useful in the discrimination between P. brasiliensis and P. lutzii , however, it does not separate between genotypes of the complex P. brasiliensis (S1, PS2, PS3 and PS4), in which recently a taxonomic rearrangeme nt was proposed, described as new species of Paracoccidioides : P. brasiliensis for S1, P. americana for PS2, P. restrepiensis for PS3 and P. venezuelensis for PS4 . In addition to the sequencing of ITS, it is necessary to include other more or less polymorp hic gene regions for phylogenetic studies aimed at identifying Paracoccidioides spp. as in this study . The objective of this work was to map out occurrence areas and isolate Paracoccidioides from armadillos ( Dasypus novemcinctus ), as well as molecularly de tect the DNA of the fungus in soil samples and organs (spleen, liver and mesenteric lymph nodes) by Nested - PCR . We isolated the armadillo fungus from the Southeast (Botucatu / SP) and Central West (Alta Floresta / MT). All isolates were molecularly charac terized by ITS - rDNA and gp43 exon 2 sequencing and by alpha tubulin (tub1) PCR - RFLP as P. brasiliensis and P. americana . The Nested - PCR reaction was sensitive and allowed to detect the DNA of Paracoccidioides in tissue samples (spleen, liver and mesenteric lymph nodes) of D. novemcinctus and also in the soil of the States of São Paulo and Mato Grosso. Phylogenetic construction with environmental soil amplicons showed that P. lutzii is widely present in these regions (Southeast and Center - West), in addition, P. lutzii amplicons from Alta Floresta / MT cluster in a clade separately, suggesting that species may exist within P. lutzii .
Paracoccidioides spp. are fungi that live in the environment (soil) and in association with tissues of mammalian hosts. They present as a characteristic of pathogenicity the thermo - dimorphism, in which, at 25º C it presents the m ycelial phase and produces its infective particles (conidia) and at 35 - 37º C it is in the form of yeasts (parasitic form). The morphological and micromorphological characteristics are important, but insufficient for the differentiation between the genotype s. However, the advance in the knowledge of Molecular Biology in recent years has allowed a great understanding of the biology and phylogenetic relationships of Paracoccidioides spp. The region of ITS1 - 5.8S - ITS2 (rDNA) has been widely used in the identific ation of several fungi, in which it is very useful in the discrimination between P. brasiliensis and P. lutzii , however, it does not separate between genotypes of the complex P. brasiliensis (S1, PS2, PS3 and PS4), in which recently a taxonomic rearrangeme nt was proposed, described as new species of Paracoccidioides : P. brasiliensis for S1, P. americana for PS2, P. restrepiensis for PS3 and P. venezuelensis for PS4 . In addition to the sequencing of ITS, it is necessary to include other more or less polymorp hic gene regions for phylogenetic studies aimed at identifying Paracoccidioides spp. as in this study . The objective of this work was to map out occurrence areas and isolate Paracoccidioides from armadillos ( Dasypus novemcinctus ), as well as molecularly de tect the DNA of the fungus in soil samples and organs (spleen, liver and mesenteric lymph nodes) by Nested - PCR . We isolated the armadillo fungus from the Southeast (Botucatu / SP) and Central West (Alta Floresta / MT). All isolates were molecularly charac terized by ITS - rDNA and gp43 exon 2 sequencing and by alpha tubulin (tub1) PCR - RFLP as P. brasiliensis and P. americana . The Nested - PCR reaction was sensitive and allowed to detect the DNA of Paracoccidioides in tissue samples (spleen, liver and mesenteric lymph nodes) of D. novemcinctus and also in the soil of the States of São Paulo and Mato Grosso. Phylogenetic construction with environmental soil amplicons showed that P. lutzii is widely present in these regions (Southeast and Center - West), in addition, P. lutzii amplicons from Alta Floresta / MT cluster in a clade separately, suggesting that species may exist within P. lutzii .
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ecologia, filogenia, Paracoccidioides spp., paracoccidioidomicose, tatus, ecology, phylogeny, armadillos, paracoccidioidomycosis