RESUMO
Systematics of Chytridiales has been deeply influenced by analyses of molecular loci and zoospore ultrastructure. Even though the Chytridiales is the largest order within Chytridiomycota, Brazilian isolates of this clade have been poorly integrated. Here, we isolated seven species and documented their morphology, including zoospore ultrastructure for Siphonaria aurea, and phylogenetic positions for all based on analyses of nuc 18S and 28S rDNA. Phylogenetic results support the placement of these species in Chytriomycetaceae and Chytridiaceae, with two new species described, Rhizidium crepaturum and Siphonaria aurea, and Rodmanochytrium sphaericum recorded for the first time from Brazil.
Assuntos
Quitridiomicetos/classificação , Quitridiomicetos/genética , DNA Fúngico/genética , Microscopia Eletrônica de Transmissão , Filogenia , Brasil , Quitridiomicetos/citologia , Quitridiomicetos/ultraestrutura , DNA Ribossômico/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Esporos Fúngicos/genéticaRESUMO
Six Nowakowskiella species from Brazil were identified and purified on corn meal agar (CMA) plus glucose and Peptonized Milk-Tryptone-Glucose (PmTG) media and placed into a phylogenetic framework for the genus. New sequence data are presented for four species: N. elongata, N. multispora, and N. ramosa and the new species N. crenulata. Our maximum likelihood and Bayesian analyses of combined 18S, 5.8S, and 28S subunits of nuc rDNA showed that Nowakowskiella is not a monophyletic clade because of the position of Nowakowskiella elongata, which is more related to Cladochytrium. We reclassify N. elongata as the type of a new genus, Karlingiella.
Assuntos
Quitridiomicetos/classificação , Quitridiomicetos/genética , Filogenia , Teorema de Bayes , Brasil , DNA Fúngico/genética , DNA Ribossômico/genética , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNARESUMO
Quantitative estimations of zoosporic fungi in the environment have historically received little attention, primarily due to methodological challenges and their complex life cycles. Conventional methods for quantitative analysis of zoosporic fungi to date have mainly relied on direct observation and baiting techniques, with subsequent fungal identification in the laboratory using morphological characteristics. Although these methods are still fundamentally useful, there has been an increasing preference for quantitative microscopic methods based on staining with fluorescent dyes, as well as the use of hybridization probes. More recently however PCR based methods for profiling and quantification (semi- and absolute) have proven to be rapid and accurate diagnostic tools for assessing zoosporic fungal assemblages in environmental samples. Further application of next generation sequencing technologies will however not only advance our quantitative understanding of zoosporic fungal ecology, but also their function through the analysis of their genomes and gene expression as resources and databases expand in the future. Nevertheless, it is still necessary to complement these molecular-based approaches with cultivation-based methods in order to gain a fuller quantitative understanding of the ecological and physiological roles of zoosporic fungi.
Assuntos
Microbiologia Ambiental , Fungos/isolamento & purificação , Contagem de Colônia Microbiana/métodosRESUMO
This article presents a survey of fungi obtained from soil, water and mixed leaf litter samples taken from the Atlantic Rainforest in the municipality of Cubatão, in the State of São Paulo, during the years of 1993 to 1995. Using different techniques for the isolation of microscopic fungi, a total of 280 taxa was obtained (66 zoosporic fungi, 40 Mucorales, 45 Glomales, 125 anamorphs, three Ascomycota and one Basidiomycota), with 23 species being reported for the first time in Brazil.
Este artigo apresenta o levantamento dos fungos obtidos de amostras de solo, água e folhedo mixto coletados da Mata Atlântica no município de Cubatão, estado de São Paulo, durante os anos de 1993 a 1995. Utilizando diferentes técnicas para isolamento de fungos microscópicos, um total de 280 táxons foram obtidos (66 fungos zoospóricos, 40 representantes de Mucorales, 45 de Glomales, 125 fungos anamorfos, três de Ascomycota e um representante de Basidiomycota), sendo 23 espécies reportadas pela primeira vez para o Brasil.