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1.
BMC Genomics ; 16: 400, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25994131

RESUMO

BACKGROUND: Pseudogymnoascus spp. is a wide group of fungi lineages in the family Pseudorotiaceae including an aggressive pathogen of bats P. destructans. Although several lineages of P. spp. were shown to produce ascospores in culture, the vast majority of P. spp. demonstrates no evidence of sexual reproduction. P. spp. can tolerate a wide range of different temperatures and salinities and can survive even in permafrost layer. Adaptability of P. spp. to different environments is accompanied by extremely variable morphology and physiology. RESULTS: We sequenced genotypes of 14 strains of P. spp., 5 of which were extracted from permafrost, 1 from a cryopeg, a layer of unfrozen ground in permafrost, and 8 from temperate surface environments. All sequenced genotypes are haploid. Nucleotide diversity among these genomes is very high, with a typical evolutionary distance at synonymous sites dS ≈ 0.5, suggesting that the last common ancestor of these strains lived >50 Mya. The strains extracted from permafrost do not form a separate clade. Instead, each permafrost strain has close relatives from temperate environments. We observed a strictly clonal population structure with no conflicting topologies for ~99% of genome sequences. However, there is a number of short (~100-10,000 nt) genomic segments with the total length of 67.6 Kb which possess phylogenetic patterns strikingly different from the rest of the genome. The most remarkable case is a MAT-locus, which has 2 distinct alleles interspersed along the whole-genome phylogenetic tree. CONCLUSIONS: Predominantly clonal structure of genome sequences is consistent with the observations that sexual reproduction is rare in P. spp. Small number of regions with noncanonical phylogenies seem to arise due to some recombination events between derived lineages of P. spp., with MAT-locus being transferred on multiple occasions. All sequenced strains have heterothallic configuration of MAT-locus.


Assuntos
Ascomicetos/fisiologia , Evolução Clonal , Genoma Fúngico , Ascomicetos/classificação , Ascomicetos/genética , Evolução Molecular , Filogenia , Reprodução Assexuada , Análise de Sequência de DNA , Especificidade da Espécie
2.
Microorganisms ; 11(2)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36838216

RESUMO

There are two main themes in the research on the biodegradation of industrial materials by mycelial fungi. The challenge of reducing environmental pollution necessitates the creation of biodegradable polymers that allow microorganisms, including mycelial fungi, to degrade them to low-molecule soluble substances. Additionally, to minimize the biodegradation of industrial materials while they are operating in the environment, there is a need to produce fungi-resistant polymer compositions. The fungal resistance of industrial materials and products can be assessed using a specific set of mycelial fungi cultures. Test cultures selected for this purpose are supported in the All-Russian Collection of Microorganisms (VKM). This review addresses the principle of culture selection to assess the fungal resistance of industrial materials and evaluates the results of the tests using these cultures.

3.
FEMS Microbiol Ecol ; 53(1): 117-28, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16329934

RESUMO

This study describes the biodiversity of the indigenous microbial community in the sodium-chloride water brines (cryopegs) derived from ancient marine sediments and sandwiched within permafrost 100-120,000 years ago after the Arctic Ocean regression. Cryopegs remain liquid at the in situ temperature of -9 to -11 degrees C and make up the only habitat on the Earth that is characterized by permanently subzero temperatures, high salinity, and the absence of external influence during geological time. From these cryopegs, anaerobic and aerobic, spore-less and spore-forming, halotolerant and halophilic, psychrophilic and psychrotrophic bacteria, mycelial fungi and yeast were isolated and their activity was detected below 0 degrees C.


Assuntos
Bactérias/genética , Fenômenos Fisiológicos Bacterianos , Biodiversidade , Fenótipo , Filogenia , Água do Mar/microbiologia , Bactérias/citologia , Bactérias/metabolismo , Sequência de Bases , Análise por Conglomerados , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sibéria , Especificidade da Espécie
4.
FEMS Microbiol Ecol ; 82(2): 501-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22757669

RESUMO

Filamentous fungi in 36 samples of Antarctic permafrost sediments were studied. The samples collected during the Russian Antarctic expedition of 2007-2009 within the framework of the Antarctic Permafrost Age Project (ANTPAGE) were recovered from different depths in ice-free oases located along the perimeter of the continent. Fungal diversity was determined by conventional microbiological techniques combined with a culture-independent method based on the analysis of internal transcribed spacer (ITS2) sequences in total DNA of the samples. The study revealed a rather low fungal population density in permafrost, although the diversity found was appreciable, representing more than 26 genera. Comparison of the data obtained by different techniques showed that the culture-independent method enabled the detection of ascomycetous and basidiomycetous fungi not found by culturing. The molecular method failed to detect members of the genera Penicillium and Cladosporium that possess small-sized spores known to have a high resistance to environmental changes.


Assuntos
Biodiversidade , Fungos/classificação , Sedimentos Geológicos/microbiologia , Regiões Antárticas , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Fungos/genética , Fungos/isolamento & purificação , Técnicas de Tipagem Micológica , Análise de Sequência de DNA
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