RESUMO
In this study, a novel genus is proposed, Scaptona, with a novel species, Scaptona ramosa, isolated from nests of stingless bees (Scaptotrigona sp.). The taxonomic novelty was determined by the phylogenetic analysis of DNA sequences from the internal transcribed spacer regions, small subunit rRNA (18S rRNA), large subunit rRNA (28S rRNA) and the RNA polymerase II second-largest subunit gene (RPB2) and paired with our morphological studies. Based on this single species, Scaptona is characterized by greyish green to dark grey colonies, densely and profusely branched conidiophores and single-celled, variously shaped hyaline conidia. Scaptona ramosa constitutes a distinct, well-supported lineage within Cephalothecaceae and can be clearly distinguished from other genera both by DNA sequence analysis and morphological traits. The holotype of S. ramosa is URM 95352. The ex-type strain has been deposited in the Micoteca URM culture collection as URM 8721T and URM 8722. The MycoBank accession number is MB 849456 for the genus and MB 849456 for the species.
Assuntos
Ácidos Graxos , Animais , Abelhas , Filogenia , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/química , RNA Ribossômico 18SRESUMO
Penicillium and Talaromyces species have a worldwide distribution and are isolated from various materials and hosts, including insects and their substrates. The aim of this study was to characterize the Penicillium and Talaromyces species obtained during a survey of honey, pollen and the inside of nests of Melipona scutellaris. A total of 100 isolates were obtained during the survey and 82% of those strains belonged to Penicillium and 18% to Talaromyces. Identification of these isolates was performed based on phenotypic characters and ß-tubulin and ITS sequencing. Twenty-one species were identified in Penicillium and six in Talaromyces, including seven new species. These new species were studied in detail using a polyphasic approach combining phenotypic, molecular and extrolite data. The four new Penicillium species belong to sections Sclerotiora (Penicillium fernandesiae sp. nov., Penicillium mellis sp. nov., Penicillium meliponae sp. nov.) and Gracilenta (Penicillium apimei sp. nov.) and the three new Talaromyces species to sections Helici (Talaromyces pigmentosus sp. nov.), Talaromyces (Talaromyces mycothecae sp. nov.) and Trachyspermi (Talaromyces brasiliensis sp. nov.). The invalidly described species Penicillium echinulonalgiovense sp. nov. was also isolated during the survey and this species is validated here.
Assuntos
Abelhas/microbiologia , Mel/microbiologia , Penicillium/classificação , Pólen/microbiologia , Talaromyces/classificação , Animais , Microbiologia Ambiental , Genes Fúngicos , Tipagem Molecular , Penicillium/genética , Penicillium/isolamento & purificação , Filogenia , Talaromyces/genética , Talaromyces/isolamento & purificaçãoRESUMO
White piedra is a fungal infection characterized by nodules comprised of Trichosporon species and restricted to the extrafollicular portion of the hair shaft. The diagnosis is based on clinical and mycological characteristics, and must be confirmed with a precise identification of the etiological agent. This research aimed to develop an in vitro infection model of white piedra and analyze its morphological and ultra-structural aspects. In the process, hair infection was induced using eight isolates of the genus Trichosporon maintained in the Culture Collection Micoteca URM. The ITS and IGS1 regions were sequenced for taxonomic confirmation. Scanning Electron Microscope (SEM) was performed at the Strategic Center for Northeast Technologies (CETENE). The scanning electron microscope was equipped with an Energy Dispersion Spectrometer (EDS). The Trichosporon isolates were identified as Trichosporon asahii (6) and Trichosporon montevideense (2) by internal transcript spacer (ITS) region and intergenic spacer 1 region (IGS1) sequencing. All eight strains were used to induce the in vitro hair infection, and nodules formed after the incubation period. Temperature variations and high humidity were not observed to be related to the development of this hair disease. The main chemical constituents detected in the nodules were carbon, nitrogen and oxygen, as well as a low level of sulfur. The absence of calcium, combined with the low level of sulfur, might explain the soft nature of the white piedra nodules. This study demonstrated that several Trichosporon species may be responsible for causing white piedra.
Assuntos
Doenças do Cabelo/microbiologia , Microscopia Eletrônica de Varredura , Piedra/diagnóstico , Piedra/microbiologia , Cálcio/química , Cabelo/ultraestrutura , Humanos , Nitrogênio/química , Oxigênio/química , Enxofre/química , TrichosporonRESUMO
Diabetic patients are at risk of acquiring esophageal infections such as those caused by members of the genus Candida. Here we describe a case in which Candida guilliermondii was isolated from the esophageal mucosa of a patient with uncontrolled diabetes mellitus. Due to inappropriate and inaccurate identification, the emergence of non-C. albicans Candida species as potential pathogens has been underestimated. This should be a cause of concern since C. guilliermondii is a normal component of human microbiota. The identity of the isolate in our case was confirmed by its characteristic morphophysiological features and amplification of rDNA using species-specific primers. Fluconazole therapy produced no improvement of the esophageal symptoms, and resistance of the etiologic agent was confirmed through in vitro susceptibility tests. This is thought to be the first documented case of C. guilliermondii esophagitis in a patient with diabetes mellitus.