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1.
Protist ; 175(2): 126023, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38368650

RESUMO

The nivicolous species of the genus Diderma are challenging to identify, and there are several competing views on their delimitation. We analyzed 102 accessions of nivicolous Diderma spp. that were sequenced for two or three unlinked genes to determine which of the current taxonomic treatments is better supported by molecular species delimitation methods. The results of a haplotype web analysis, Bayesian species delimitation under a multispecies coalescent model, and phylogenetic analyses on concatenated alignments support a splitting approach that distinguishes six taxa: Diderma alpinum, D. europaeum, D. kamchaticum, D. meyerae, D. microcarpum and D. niveum. The first two approaches also support the separation of Diderma alpinum into two species with allopatric distribution. An extended dataset of 800 specimens (mainly from Europe) that were barcoded with 18S rDNA revealed only barcode variants similar to those in the species characterized by the first data set, and showed an uneven distribution of these species in the Northern Hemisphere: Diderma microcarpum and D. alpinum were the only species found in all seven intensively sampled mountain regions. Partial 18S rDNA sequences serving as DNA barcodes provided clear signatures that allowed for unambiguous identification of the nivicolous Diderma spp., including two putative species in D. alpinum.


Assuntos
Mixomicetos , Código de Barras de DNA Taxonômico/métodos , Teorema de Bayes , Filogenia , DNA Ribossômico/genética
2.
Microorganisms ; 11(8)2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37630589

RESUMO

Typhulaceae Jülich is one of the cold-adapted fungal families in basidiomycetes. The representative genera, Typhula (Pers.) Fr. and Pistillaria Fr., are distinguished by the discontinuity between stems and hymenia in the former and the continuity in the latter (Fries 1821). This taxonomic criterion is ambiguous, and consequently, the view of Karsten (1882) has been widely accepted: Typhula develops basidiomata from sclerotia, while basidiomata develop directly from substrata in Pistillaris. However, Corner (1970) observed basidiomata of Pistillaria petasitis S. Imai developing from sclerotia in Hokkaido, Japan. We later recognized that P. petasitis basidiomata also emerged directly from substrates on the ground in Hokkaido. An aberrant form of Typhula hyperborea H. Ekstr. was found in Upernavik, West Greenland. This specimen had a stem-like structure on a Poaceae plant, and sclerotia developed on its tip. Similar phenomena were found in other Typhula species in Japan. In this study, we aimed to elucidate the life cycle plasticity in the genera Typhula and Pistillaria through the interactions between their ecophysiological potential and environmental conditions in their localities. We collected and prepared strains of the above fungi from sclerotia or basidiomata, and we elucidated the taxonomical relationship and determined the physiological characteristics of our strains. Our findings imply that both Typhula and Pistillaria have the potential to produce sclerotia as well as the capacity for mycelial growth at ambient air temperatures in each locality where samples were collected. These findings suggest that Typhula spp. develope basidiomata not only from the sclerotia dispersed by the basidiospores but also from mycelia generated by the spore germination, which formed basidiomata multiple times, depending on their growth environments.

3.
Mycologia ; 115(2): 236-254, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36877890

RESUMO

The noncellular complex structures of fruiting body produced by a multinucleate large plasmodium are the distinct character of Myxomycetes. Although the fruiting body distinguishes myxomycetes from other amoeboid single-cell organisms, it is unclear how such complex structures arise out of a single cell. The present study investigated the detailed process of fruiting body formation in Lamproderma columbinum, the type species of the genus Lamproderma, at the cellular level. A single cell excretes cellular waste and excess water during the formation of the fruiting body by controlling its shape, secreted materials, and organelle distribution. These excretion phenomena lead to the morphology of the mature fruiting body. The results of this study suggest that the structures of the L. columbinum fruiting body are involved not merely in spore dispersal but also in the process of dehydration and self-cell cleaning of the single cell for the next generation.


Assuntos
Mixomicetos , Humanos , Desidratação
4.
Mycologia ; 115(2): 225-235, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36867578

RESUMO

Despite various attempts during the last few decades to establish a natural system for the Myxomycetes, researchers have not yet reached a consensus. One of the most drastic recent proposals is the movement of the genus Lamproderma, an almost a trans-subclass transfer. The traditional subclasses are not supported by current molecular phylogenies, and various higher classifications have been proposed during the last decade. However, the taxonomic characteristics on which the traditional higher classifications were based have not been reinvestigated. In the present study, the key species involved in this transfer, Lamproderma columbinum (the type species of the genus Lamproderma), was assessed using correlational morphological analysis of stereo, light, and electron microscopic images. Correlational analysis of the plasmodium, fruiting body formation, and the mature fruiting bodies revealed that several concepts of taxonomic characteristics that have been used to distinguish higher classifications are questionable. The results of this study indicate that caution is required when interpreting the evolution of morphological traits in Myxomycetes, as the current concepts are vague. The definitions of the taxonomic characteristics need a detailed research, and attention should be paid to the lifecycle timing of observations, before discussing a natural system for Myxomycetes.


Assuntos
Mixomicetos , Mixomicetos/genética , Filogenia , Reprodução
5.
Mol Ecol ; 31(1): 372-390, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34676941

RESUMO

Myxomycetes are terrestrial protists with many presumably cosmopolitan species dispersing via airborne spores. A truly cosmopolitan species would suffer from outbreeding depression hampering local adaptation, while locally adapted species with limited distribution would be at a higher risk of extinction in changing environments. Here, we investigate intraspecific genetic diversity and phylogeography of Physarum albescens over the entire Northern Hemisphere. We sequenced 324 field collections of fruit bodies for 1-3 genetic markers (SSU, EF1A, COI) and analysed 98 specimens with genotyping by sequencing. The structure of the three-gene phylogeny, SNP-based phylogeny, phylogenetic networks, and the observed recombination pattern of three independently inherited gene markers can be best explained by the presence of at least 18 reproductively isolated groups, which can be seen as cryptic species. In all intensively sampled regions and in many localities, members of several phylogroups coexisted. Some phylogroups were found to be abundant in only one region and completely absent in other well-studied regions, and thus may represent regional endemics. Our results demonstrate that the widely distributed myxomycete species Ph. albescens represents a complex of at least 18 cryptic species, and some of these seem to have a limited geographical distribution. In addition, the presence of groups of presumably clonal specimens suggests that sexual and asexual reproduction coexist in natural populations of myxomycetes.


Assuntos
Amebozoários , Physarum , Sequência de Bases , Variação Genética , Genótipo , Filogenia
6.
Sci Rep ; 10(1): 5757, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32238824

RESUMO

Imaging mass spectrometry (IMS) has been rarely used to examine specimens of human brain tumours. In the current study, high quality brain tumour samples were selected by tissue observation. Further, IMS analysis was combined with a new hierarchical cluster analysis (IMS-HCA) and region of interest analysis (IMS-ROI). IMS-HCA was successful in creating groups consisting of similar signal distribution images of glial fibrillary acidic protein (GFAP) and related multiple proteins in primary brain tumours. This clustering data suggested the relation of GFAP and these identified proteins in the brain tumorigenesis. Also, high levels of histone proteins, haemoglobin subunit α, tubulins, and GFAP were identified in a metastatic brain tumour using IMS-ROI. Our results show that IMS-HCA and IMS-ROI are promising techniques for identifying biomarkers using brain tumour samples.


Assuntos
Química Encefálica , Neoplasias Encefálicas/patologia , Encéfalo/patologia , Proteínas/análise , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/química , Análise por Conglomerados , Humanos , Peptídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
7.
Sci Rep ; 8(1): 7493, 2018 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-29748547

RESUMO

Matrix-assisted laser desorption ionization image mass spectrometry (MALDI-IMS) has been developed for the identification of peptides in various tissues. The MALDI-IMS signal distribution patterns and quantification of the signal intensities of the regions of interest (ROI) with healthy regions were compared for identification of the disease specific biomarkers. We performed a new ROI analysis using the conventional t-test and data number independent Cohen's d-value analysis. Using these techniques, we analysed heart tissues after acute myocardial infarction (AMI). As a result, IMS signals of mitochondrial adenosine triphosphate synthase alpha subunit (ATP5A), myosin-6/7(MYH6/7), aortic actin, and the myosin light chain 3 (MYL3) were identified in the infarcted region. In particular, the signals of MYH7 are significantly greater in the infarcted region using ROI analysis. ROI analysis using MALDI-IMS may be a promising technique for the identification of biomarkers for pathological studies that involve the comparison of diseased and control areas.


Assuntos
Mitocôndrias Cardíacas/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Musculares/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Sarcômeros/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Autopsia , Biomarcadores/análise , Biomarcadores/metabolismo , Estudos de Casos e Controles , Humanos , Mitocôndrias Cardíacas/patologia , Proteínas Mitocondriais/análise , Proteínas Musculares/análise , Sarcômeros/patologia , Remodelação Vascular , Remodelação Ventricular
8.
J Pharmacol Sci ; 134(2): 108-115, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28648300

RESUMO

Previously, we reported that specific lower dose of sodium 2,3-dimercapto-1-propanesulfonic acid (DMPS) which is an antidote to heavy metal intoxication, inversely enhanced cisplatin (CDDP)-induced antitumor activity to S-180 cell-bearing mouse. This activity was only weak with meso-2,3-dimercaptosuccinic acid (DMSA), however. This study investigated the effects of lower doses of DMPS or DMSA on the nephrotoxicity and kinetics of CDDP. Kidney and blood isolated from female mice which received CDDP with or without DMPS or DMSA once daily for 4 days were provided for measuring levels of blood urea nitrogen (BUN) and transporter proteins (OCT2: organic cation transporter; MATE1: multidrug and toxin extrusion) mRNA, and CDDP-originated platinum, and TUNEL staining of renal tubular cells. DMPS or DMSA reduced effectively CDDP-induced BUN, and caused a moderate reduction of platinum in kidney. Additionally, both dimercapto-compounds restored the CDDP-reduced mRNA levels of transporter proteins (OCT2 and MATE1), and apparently suppressed the CDDP-induced apoptosis. These results suggest that DMPS, as well as DMSA, at approximate 17-fold dose (µmol/kg) of CDDP, has an enough potential to reverse the CDDP nephrotoxicity, and concomitant use of DMPS considering both dose and timing for administration is potentially useful for preventing nephrotoxicity and enhancing antitumor activity during CDDP chemotherapy.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Nefropatias/tratamento farmacológico , Succímero/uso terapêutico , Unitiol/uso terapêutico , Animais , Relação Dose-Resposta a Droga , Feminino , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/patologia , Camundongos , Proteínas de Transporte de Cátions Orgânicos/genética , Proteínas de Transporte de Cátions Orgânicos/metabolismo , Transportador 2 de Cátion Orgânico/genética , Transportador 2 de Cátion Orgânico/metabolismo , RNA Mensageiro/metabolismo , Succímero/farmacologia , Unitiol/farmacologia
9.
Bioresour Technol ; 234: 99-105, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28319778

RESUMO

Synthetic wastewater (SW) at various carbon concentrations (5-60g/l) were evaluated for polyhydroxyalkanoates (PHA) production using the bacteria Pseudomonas pseudoflava. Bacteria showed highest PHA production with 20g/l (57±5%), and highest carbon removal at 5g/l (74±6%) concentrations respectively. Structure, molecular weight, and thermal properties of the produced PHA were evaluated using various analytical techniques. Bacteria produced homo-polymer [poly-3-hydroxybutyrate (P3HB)] when only acetate was used as carbon source; and it produced co-polymer [poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV)] by addition of co-substrate propionate. PHA synthase, the enzyme which produce PHA was extracted from two bacterial strains i.e., P. pseudoflava and P. palleronii and its molecular weight was analysed using SDS-PAGE. Protein concentration, and PHA synthase enzyme activity of P. pseudoflava and P. palleronii was carried out using spectrophotometer. Results denoted that P. pseudoflava can be used for degradation of organic carbon persistent in wastewaters and their subsequent conversion into PHA.


Assuntos
Poliésteres/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Carbono/metabolismo , Comamonadaceae , Pseudomonas/metabolismo , Águas Residuárias
10.
Mycology ; 8(3): 147-152, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30123636

RESUMO

We collected snow blight of moss, Polytrichum juniperinum on King George Island, maritime Antarctica. Host died in a circle of about 10-30 cm after snow melts. Clamp connected hyphae and no sclerotia were observed on tip of host leaves. DNA sequence of ITS region from moss symptoms were perfectly matched with fruit bodies of Typhula sp. on Macquarie Island in the maritime Antarctica and high homology with Typhula cf. subvariabilis from Iran. Therefore, we suggested that T. cf. subvariabilis caused snow blight on moss in Antarctica, and this is first record of Typhula snow blight in Southern Hemisphere. These results also suggested that fungi in same genera gained similar ecological niche in both Polar Regions.

11.
Bioresour Technol ; 215: 155-162, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26995321

RESUMO

In the present study, synthetic wastewater (SW) was used for production of poly-3-hydroxybutyrate (P3HB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV) using the bacteria Hydrogenophaga palleronii. SW at various volatile fatty acids concentrations (5-60g/l) was evaluated for the growth and biopolymer production using H. palleronii. Substrate degradation was analyzed using total organic carbon (TOC) analyzer and high pressure liquid chromatography (HPLC). H. palleronii showed highest and lowest removal of TOC at 5g/l (88±4%) and 60g/l (15±6%) respectively. Among all the concentrations evaluated, bacteria showed highest biopolymer production with 20g/l (63±5%), followed by 30g/l (58±3%) and 40g/l (56±2%). Lowest biopolymer production was observed at 5g/l concentration (21±3%). Structure, molecular weight, and thermal properties of the produced biopolymer were analyzed. These results denoted that the strain H. palleronii can be used for degradation of high concentration of volatile fatty acids persistent in wastewaters and their subsequent conversion into useable biopolymers.


Assuntos
Comamonadaceae/metabolismo , Ácidos Graxos Voláteis/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Poluentes Químicos da Água/metabolismo , Concentração de Íons de Hidrogênio , Peso Molecular , Ácidos Pentanoicos/metabolismo , Águas Residuárias/química , Purificação da Água
12.
PLoS One ; 10(12): e0145057, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26710231

RESUMO

In the present study, a 2,4-dichlorophenoxyacetic acid (2,4-D) degrading bacterial strain CY-1 was isolated from the forest soil. Based on physiological, biochemical and 16S rRNA gene sequence analysis it was identified as Cupriavidus sp. CY-1. Further 2,4-D degradation experiments at different concentrations (200 to 800 mg l(-1)) were carried out using CY-1. Effect of NaCl and KNO3 on 2,4-D degradation was also evaluated. Degradation of 2,4-D and the metabolites produced during degradation process were analyzed using high pressure liquid chromatography (HPLC) and GC-MS respectively. The amount of chloride ions produced during the 2,4-D degradation were analyzed by Ion chromatography (IC) and it is stoichiometric with 2,4-D dechlorination. Furthermore two different types of soils collected from two different sources were used for 2,4-D degradation studies. The isolated strain CY-1 was bio-augmented into 2,4-D contaminated soils to analyze its degradation ability. Culture independent methods like denaturing gradient gel electrophoresis (DGGE) and terminal restriction fragment length polymorphism (T-RFLP), and culture dependent methods like colony forming units (CFU) and most probable number (MPN) were used to analyze the survivability of strain CY-1 in contaminated soil. Results of T-RFLP were coincident with the DGGE analysis. From the DGGE, T-RFLP, MPN and HPLC results it was concluded that strain CY-1 effectively degraded 2,4-D without disturbing the ecosystem of soil indigenous microorganisms.


Assuntos
Ácido 2,4-Diclorofenoxiacético/metabolismo , Biodegradação Ambiental , Cupriavidus/isolamento & purificação , Cupriavidus/metabolismo , Herbicidas/metabolismo , Poluentes do Solo/metabolismo , Biodiversidade , Cromatografia Líquida de Alta Pressão , Cupriavidus/genética , DNA Bacteriano/genética , Eletroforese em Gel de Gradiente Desnaturante , Ecossistema , Cromatografia Gasosa-Espectrometria de Massas , Nitratos/química , Polimorfismo de Fragmento de Restrição , Compostos de Potássio/química , RNA Ribossômico 16S/genética , Cloreto de Sódio/química , Solo/química , Microbiologia do Solo
13.
Bioresour Technol ; 192: 711-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26101960

RESUMO

In the present study five different types of alkylphenols, each of the two different types of mono and poly-aromatic hydrocarbons were selected for degradation, and conversion into poly-3-hydroxybutyrate (PHB) using the Bacillus sp. CYR1. Strain CYR1 showed growth with various toxic organic compounds. Degradation pattern of all the organic compounds at 100 mg/l concentration with or without addition of tween-80 were analyzed using high pressure liquid chromatography (HPLC). Strain CYR1 showed good removal of compounds in the presence of tween-80 within 3 days, but it took 6 days without addition of tween-80. Strain CYR1 showed highest PHB production with phenol (51 ± 5%), naphthalene (42 ± 4%), 4-chlorophenol (32 ± 3%) and 4-nonylphenol (29 ± 3%). The functional groups, structure, and thermal properties of the produced PHB were analyzed. These results denoted that the strain Bacillus sp. CYR1 can be used for conversion of different toxic compounds persistent in wastewaters into useable biological polyesters.


Assuntos
Bacillus/classificação , Bacillus/metabolismo , Hidroxibutiratos/metabolismo , Fenóis/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poliésteres/metabolismo , Alquilação , Biodegradação Ambiental , Hidroxibutiratos/isolamento & purificação , Resíduos Industriais/prevenção & controle , Fenóis/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Poliésteres/isolamento & purificação , Reciclagem/métodos , Especificidade da Espécie , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos
14.
Cryobiology ; 70(2): 208-10, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25661659

RESUMO

Oomyceteous snow molds, Pythium species, were reported to be less tolerant to chilling and freezing temperatures than other snow mold taxa. However, Pythium species are often found to be pathogenic on mosses in Polar Regions. We investigated the frost resistance of Pythium species from Temperate (Hokkaido, Japan) and Subantarctic Regions. Free mycelia and hyphal swellings, structures for survival, of Pythium iwayamai and Pythium paddicum lost viability within freeze-thaw 3 cycles; however, mycelia in host plants survived the treatment. It was reported that fungi in permafrost are characterized both by the presence of natural cryoprotectants in these ecotopes and by the ability to utilize their inherent mechanisms of protection. It is conceivable that plant substrates or derivatives thereof are natural cryoprotectants, enabling them to provide advantageous conditions to microorganisms under freezing conditions. Our results are the first to experimentally support this hypothesis.


Assuntos
Adaptação Fisiológica/fisiologia , Crioprotetores/metabolismo , Congelamento/efeitos adversos , Pythium/fisiologia , Sobrevivência Celular , Temperatura Baixa , Plantas
15.
Int J Med Mushrooms ; 15(2): 175-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23557369

RESUMO

Ganoderic acid A and α- and ß-D-glucan content were compared among morphologically different basidiocarps of the medicinal mushroom Ganoderma lucidum. Ginkgo leaf-shaped basidiocarps gradually hardened from the base to the pileus and accumulated a higher amount of bioactive components than normal (kidney-shaped) and antler/deer horn-shaped basidiocarps. In the normal G. lucidum stipe, the outer context contained the highest amount of α- and ß-D-glucan (approximately 55%) and the highest amount of ganoderic acid A (approximately 0.3%). Ginkgo leaf-shaped G. lucidum had a large area of outer layer and stout outer context, which contributed to their high α- and ß-D-glucan and ganoderic acid A content.


Assuntos
Carpóforos/química , Carpóforos/ultraestrutura , Ganoderma/química , Ganoderma/ultraestrutura , Glucanos/química , Ácidos Heptanoicos/química , Lanosterol/análogos & derivados , Técnicas de Cultura , Carpóforos/metabolismo , Glucanos/metabolismo , Ácidos Heptanoicos/metabolismo , Hifas , Lanosterol/química , Lanosterol/metabolismo
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