-
The Journal of General and Applied... Feb 2021Aureobasidium pullulans YTP6-14 was demonstrated to be an excellent multiple biosurfactant producer utilizing cheap carbon sources available in Thailand, including...
Aureobasidium pullulans YTP6-14 was demonstrated to be an excellent multiple biosurfactant producer utilizing cheap carbon sources available in Thailand, including glycerol and cassava flour hydrolysate. A. pullulans YTP6-14 maximally produced 1.81 g/l biosurfactant in an aqueous layer (BS-AQ) in a medium containing glycerol, and 7.37 or 6.37 g/l biosurfactant in a heavy oil layer (BS-HO) in cassava flour hydrolysate or a glucose containing medium, respectively. Each BS-AQ and BS-HO had critical micelle concentration values of 41.32 mg/l and 13.51 mg/l, and both biosurfactants formed a stable food oil emulsion and reduced the amount of biofilms formed by Streptococcus sobrinus and Streptococcus mutans. BS-AQ and BS-HO were mainly composed of liamocins or exophilins and massoia lactone, respectively.
Topics: Anti-Bacterial Agents; Aureobasidium; Biofilms; Oils; Streptococcus mutans; Streptococcus sobrinus; Surface-Active Agents
PubMed: 33012773
DOI: 10.2323/jgam.2020.01.011 -
International Journal of Molecular... Sep 2023Ulcerative colitis (UC), a subtype of inflammatory bowel disease, is a chronic gastrointestinal inflammatory disease with unclear etiology and pathophysiology. Herein,...
Ulcerative colitis (UC), a subtype of inflammatory bowel disease, is a chronic gastrointestinal inflammatory disease with unclear etiology and pathophysiology. Herein, we determined the effects of extracellular polysaccharides purified from SM-2001 (Polycan) on tight junction protein expression, inflammation, and apoptosis in a dextran sodium sulfate (DSS)-induced acute colitis model. Fifty mice were divided into normal, DSS, DSS + Polycan 250 mg/kg (Polycan 250), DSS + Polycan 500 mg/kg (Polycan 500), and DSS + 5-aminosalicylic acid 100 mg/kg (5-ASA) groups. Their body weights, colon lengths, histological changes in colon tissue, and tight junction function were observed. Results showed that Polycan 250, Polycan 500, and 5-ASA significantly inhibited body weight loss compared with DSS. Similar to 5-ASA, Polycan 500 exhibited preventive effects on colon length shortening and histological changes in colon tissues. Polycan inhibited the DSS-induced decrease in fluorescein isothiocyanate-dextran permeability and myeloperoxidase activity. Moreover, Polycan significantly recovered serum cytokine (e.g., tumor necrosis factor-α, interleukin (IL)-6, and IL-1β) or mRNA expression in colon tissue compared with DSS. Polycan also inhibited apoptosis by reducing caspase-3 activity and the Bcl-2 associated X/B-cell lymphoma 2 (Bcl-2) ratio. Additionally, DSS treatment significantly reduced microbial abundance and diversity, but the administration of Polycan reversed this effect. Collectively, Polycan protected intestinal barrier function and inhibited inflammation and apoptosis in DSS-induced colitis.
Topics: Animals; Mice; Colitis, Ulcerative; Dextrans; Glucans; beta-Glucans; Colitis; Colon; Inflammation; Interleukin-6; Mesalamine; Proto-Oncogene Proteins c-bcl-2; Dextran Sulfate; Disease Models, Animal; Mice, Inbred C57BL
PubMed: 37834221
DOI: 10.3390/ijms241914773 -
Journal of Fungi (Basel, Switzerland) May 2023One hundred twenty-five yeast strains isolated from table grapes and apples were evaluated for the control of in vitro and in vivo. Ten strains were selected for their...
One hundred twenty-five yeast strains isolated from table grapes and apples were evaluated for the control of in vitro and in vivo. Ten strains were selected for their ability to inhibit mycelial growth of in vitro. In the in vivo assays, these yeasts were tested at 20 °C on 'Thompson Seedless' berries for 7 days; only three were selected (m11, me99 and ca80) because they significantly reduced the incidence of gray mold. These three yeast strains were then evaluated at different concentrations (1 × 10, 1 × 10 and 1 × 10 cells mL) on 'Thompson Seedless' grape berries at 20 °C. The strains m11, me99 and ca80 reduced the incidence of to 11.9, 26.1 and 32.1%, respectively, when the berries were submerged in a yeast suspension at a concentration of 1 × 10 cells mL 24 h before inoculation with . The most favorable pH for antifungal activity was 4.6 in the three isolates. The three yeast strains secreted the hydrolytic enzymes chitinase and β-1-glucanase, and two strains (me99 and ca80) produced siderophores. The three yeast strains exhibited low oxidative stress tolerance and only strain m11 had the ability to produce biofilms. The strains were identified using 5.8S-ITS rDNA PCR-RFLP and correspond to the (m11) and (me99 and ca80) species.
PubMed: 37233268
DOI: 10.3390/jof9050557 -
Plant Disease Jan 2022Asian pear (Pyrus pyrifolia Nakai cv. cuiguan), is widely grown in Zhejiang province of China. In April 2019, symptoms consisting of small black, round leaf spots and...
Asian pear (Pyrus pyrifolia Nakai cv. cuiguan), is widely grown in Zhejiang province of China. In April 2019, symptoms consisting of small black, round leaf spots and blight flower petals were observed on over 30 % of 'Cuiguan' pear trees in an orchard (ca. 0.8 ha) near Cixi city, Zhejiang province, China. Initially, leaf spots were observed on leaf petioles, which, with time, enlarged and coalesced into necrotic streaks (1-2 cm) along the length of the petioles. Irregularly, reddish brown spots developed on flower petals, which hastened their senescence. Additional symptoms included round, black spots on leaves (2-3 mm in diameter) and necrosis of shoot tips. Symptomatic tissues from petals, petioles and leaves were plated onto potato dextrose agar (PDA). After five days of incubation at 26 °C, slimy fungal colonies (48×48 mm) with pinkish to orange-colored mycelia and with regular annulations were isolated from all tissues. After 10 days, cultured were shiny and dark brown in the center. The color of conidia ranged from hyaline to dark brown. Hyaline conidia were blastic, unicellular, ellipsoidal, smooth, with lengths that ranged from 11.03 to 27.14 (avg. 18.38) μm, and widths that ranged from 3.45 to 8.86 (avg. 6.04) μm (n = 50). Dark brown conidia were 1 to 2 celled, 10.89 to 26.03 (avg. 17.41) μm in length and 4.26 to 12.15 (avg. 6.94) μm in width (n = 50), and a slight septal constriction. Conidiogenous cells were clavate, hyaline, eseptate and top smoothly with 3-11 spores. Indistinct scars remained when the conidia dislodge from the conidiogenous cells. Single spore isolation was used to obtain pure cultures. Mycelia and conidia were scraped from cultures and DNA was extracted using Ezup Column Fungi Genomic DNA Purification Kit (Sangon Biotech). Amplified PCR products from the internal transcribed spacer (ITS) region ITS1F/ITS4 (White et al. 1990), the partial 28S rDNA (LSU) NL1/NL4 (Boekhout et al. 1995), the β-tubulin (TUB) gene Bt2a/Bt2b (Glass & Donaldson 1995) and the partial elongase gene (ELO) ELO2-F/ELO2-R (Zalar et al. 2008) were sequenced (Tsingke Biotechnology Co., Hangzhou, Zhejiang). A blast search (GenBank Accession No. MT107050, OK485685, OK631951, OK631950) showed 99% Aureobasidium pullulans reference isolate CBS584.75 and EXF-150, which was consistent with the morphological data (Cene et al. 2014). Three-yr-old seedlings from 'Cuiguan' pears were spray with conidial suspension (106 conidia/ml) on the both sides of leaves without wounding. In a greenhouse (26 °C, natural light), six inoculated plants and three noninoculated plants (sprayed with sterile distilled water) enclosed in plastic bags to maintain humidity for 72 h. At 5 days after inoculation, shoot tips blackened and began to wilt. At 15 days after inoculation, symptoms similar to those on the original sample developed on inoculated petioles and leaves, whereas the control plants remained healthy. No symptoms were observed on leaves that were mature at the time of inoculation. Aureobasidium pullulans var. pullulans was reisolated from all inoculated plant. Overall, this disease shortened the life of pear flowers and reduced fruit set. To our knowledge, A. pullulans var. pullulans has not previously been reported as a pathogen of P. pyrifolia.
PubMed: 35100838
DOI: 10.1094/PDIS-10-21-2367-PDN -
Current Medical Mycology Sep 2021The frequency and genetic diversity of black fungi in environmental and clinical settings have not been fully studied in Iran. This study aimed to identify and evaluate...
BACKGROUND AND PURPOSE
The frequency and genetic diversity of black fungi in environmental and clinical settings have not been fully studied in Iran. This study aimed to identify and evaluate intra- and inter-species DNA sequence variation and also understand the phylogenetic relationships of melanized fungi and relatives isolated from different geographical regions of Iran.
MATERIALS AND METHODS
In total, 111 clinical and environmental strains of dematiaceous fungi were isolated, and their internal transcribed spacer ribosomal DNA (rDNA) regions were sequenced and analyzed.
RESULTS
An inter-species nucleotide sequence diversity rate of 1 to 464 nucleotides was observed between the species. Intra-species differences were found in the strains of and by 0-59, 0-22, 0-4, 0-4, 0-3, 0-2, 0-2, 0-2, 0-2, 0-1, and 0-1 nucleotide, respectively.
CONCLUSION
The internal transcribed spacer rDNA is useful for the discrimination of several taxa of dematiaceous fungi. However, a better understanding of the taxonomy of species of requires a larger rDNA region or a library of other gene sequences.
PubMed: 35528626
DOI: 10.18502/cmm.7.3.7798 -
Phytopathology Feb 2022Gray mold caused by is a common postharvest disease in strawberries, reducing shelf life considerably. We investigated the potential of the yeast-like biocontrol fungus...
Gray mold caused by is a common postharvest disease in strawberries, reducing shelf life considerably. We investigated the potential of the yeast-like biocontrol fungus (AP-SLU6) vectored by bumblebees () in the Flying Doctors system to inhibit the pathogen and increase the shelf life of harvested strawberries (cultivar Sonata). Using bumblebees as vectors of various biocontrol agents is becoming increasingly popular, but any potentially negative effects on bee performance have been understudied. Our results show that, over the 4-week period of the trial, the performance and activity of the bees were not negatively affected by . . The bees successfully picked up the powder formulation; then, they carried and deposited it on the flowers. The vectoring of the biocontrol agent significantly reduced gray mold development on the harvested fruits by 45% and increased shelf life by 100% in comparison with control treatments. This suggests that the biocontrol fungus applied during flowering successfully reduced infection and thus, effectively protected the fruits from gray mold. In addition, the bee-vectored application of the biocontrol agent was found to be significantly more effective than spray application because the latter may temporarily increase humidity around the flower, thereby creating a suitable environment for the pathogen to thrive. In summary, our study demonstrates that . vectored by bumblebees can decrease gray mold infection and improve the shelf life of strawberries without adversely affecting the bees, thus providing a basis for the sustainable and efficient control of gray mold on strawberry.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.
Topics: Animals; Aureobasidium; Bees; Botrytis; Fragaria; Fruit; Plant Diseases
PubMed: 34181440
DOI: 10.1094/PHYTO-05-21-0205-R -
Journal of Fungi (Basel, Switzerland) Feb 2023Flax ( L.) is attacked by numerous devastating fungal pathogens, including , , and (). The effective control of flax diseases follows the paradigm of extensive...
Flax ( L.) is attacked by numerous devastating fungal pathogens, including , , and (). The effective control of flax diseases follows the paradigm of extensive molecular research on pathogenicity. However, such studies require quality genome sequences of the studied organisms. This article reports on the approaches to assembling a high-quality fungal genome from the Oxford Nanopore Technologies data. We sequenced the genomes of , , and () and received different volumes of sequencing data: 1.7 Gb, 3.9 Gb, and 11.1 Gb, respectively. To obtain the optimal genome sequences, we studied the effect of input data quality and genome coverage on assembly statistics and tested the performance of different assembling and polishing software. For , the most contiguous and complete assembly was obtained by the Flye assembler and the Homopolish polisher. The genome coverage had more effect than data quality on assembly statistics, likely due to the relatively low amount of sequencing data obtained for . The final assembly was 53.4 Mb long and 96.4% complete (according to the glomerellales_odb10 BUSCO dataset), consisted of 42 contigs, and had an N50 of 4.4 Mb. For and (), the best assemblies were produced by Canu-Medaka and Canu-Homopolish, respectively. The final assembly of had a length of 29.5 Mb, 99.4% completeness (dothideomycetes_odb10), an N50 of 2.4 Mb and consisted of 32 contigs. () assembly was 44.1 Mb long, 97.8% complete (hypocreales_odb10), consisted of 54 contigs, and had an N50 of 4.4 Mb. The obtained results can serve as a guideline for assembling a de novo genome of a fungus. In addition, our data can be used in genomic studies of fungal pathogens or plant-pathogen interactions and assist in the management of flax diseases.
PubMed: 36983469
DOI: 10.3390/jof9030301 -
TheScientificWorldJournal 2020Some studies have reported the occurrence of microorganisms isolated from water. Considering these microorganisms, fungi are known to occur ubiquitously in the...
INTRODUCTION
Some studies have reported the occurrence of microorganisms isolated from water. Considering these microorganisms, fungi are known to occur ubiquitously in the environment, including water, and some are pathogenic and may cause health problems, especially in immunocompromised individuals. The aim of this study was to identify fungi in hospital water samples and to correlate their presence with the concentration of free residual chlorine.
METHODS
Water samples (100 mL) were collected from taps ( = 74) and water purifiers ( = 14) in different locations in a university hospital. Samples were filtered through a nitrocellulose membrane and placed on Sabouraud dextrose agar and incubated for 24 hours at 30°C. Fungi were identified according to established methods based on macroscopic and microscopic characteristics (filamentous) and physiological tests (yeasts). Free chlorine residual content was measured at the time of sample collection.
RESULTS
Seventy species of fungi were identified in the water samples and about 56% of the water samples contained culturable fungi. , , and were the most common filamentous fungi. and were the most common yeasts. Chemical analyses revealed that free residual chlorine was present in 81.8% of the samples within recommended concentrations. Among samples from water purifiers, 92.9% showed low levels of free residual chlorine (<0.2 mg/L). There was no significant association between chlorine concentrations (either within or outside the recommended range) and the presence of filamentous fungi and yeasts.
CONCLUSIONS
This study showed that hospital water can be a reservoir for fungi, some of which are potentially harmful to immunocompromised patients. Free residual chlorine was ineffective in some samples.
Topics: Aspergillus fumigatus; Aureobasidium; Biodiversity; Biofilms; Brazil; Candida parapsilosis; Chlorine; Cladosporium; Fungi; Hospitals, University; Humans; Mycoses; Penicillium; Water; Water Microbiology; Water Supply
PubMed: 32694957
DOI: 10.1155/2020/9358542 -
International Journal of Molecular... Nov 2023(), a commonly found yeast-like fungus, exhibits adaptability to a wide range of pH environments. However, the specific mechanisms and regulatory pathways through which...
(), a commonly found yeast-like fungus, exhibits adaptability to a wide range of pH environments. However, the specific mechanisms and regulatory pathways through which respond to external pH remain to be fully understood. In this study, we first sequenced the whole genome of using Nanopore technology and generated a circle map. Subsequently, we explored the biomass, pullulan production, melanin production, and polymalic acid production of when cultivated at different pH levels. We selected pH 4.0, pH 7.0, and pH 10.0 to represent acidic, neutral, and alkaline environments, respectively, and examined the morphological characteristics of using SEM and TEM. Our observations revealed that predominantly exhibited hyphal growth with thicker cell walls under acidic conditions. In neutral environments, it primarily displayed thick-walled spores and yeast-like cells, while in alkaline conditions, it mainly assumed an elongated yeast-like cell morphology. Additionally, transcriptome analysis unveiled that orchestrates its response to shifts in environmental pH by modulating its cellular morphology and the expression of genes involved in pullulan, melanin, and polymalic acid synthesis. This research enhances the understanding of how regulates itself in diverse pH settings and offers valuable guidance for developing and applying engineered strains.
Topics: Ascomycota; Saccharomyces cerevisiae; Melanins; Gene Expression Profiling; Hydrogen-Ion Concentration; Fermentation
PubMed: 38003294
DOI: 10.3390/ijms242216103 -
GigaScience Oct 2022The great diversity of lifestyles and survival strategies observed in fungi is reflected in the many ways in which they reproduce and recombine. Although a complete...
BACKGROUND
The great diversity of lifestyles and survival strategies observed in fungi is reflected in the many ways in which they reproduce and recombine. Although a complete absence of recombination is rare, it has been reported for some species, among them 2 extremotolerant black yeasts from Dothideomycetes: Hortaea werneckii and Aureobasidium melanogenum. Therefore, the presence of diploid strains in these species cannot be explained as the product of conventional sexual reproduction.
RESULTS
Genome sequencing revealed that the ratio of diploid to haploid strains in both H. werneckii and A. melanogenum is about 2:1. Linkage disequilibrium between pairs of polymorphic loci and a high degree of concordance between the phylogenies of different genomic regions confirmed that both species are clonal. Heterozygosity of diploid strains is high, with several hybridizing genome pairs reaching the intergenomic distances typically seen between different fungal species. The origin of diploid strains collected worldwide can be traced to a handful of hybridization events that produced diploids, which were stable over long periods of time and distributed over large geographic areas.
CONCLUSIONS
Our results, based on the genomes of over 100 strains of 2 black yeasts, show that although they are clonal, they occasionally form stable and highly heterozygous diploid intraspecific hybrids. The mechanism of these apparently rare hybridization events, which are not followed by meiosis or haploidization, remains unknown. Both extremotolerant yeasts, H. werneckii and even more so A. melanogenum, a close relative of the intensely recombining and biotechnologically relevant Aureobasidium pullulans, provide an attractive model for studying the role of clonality and ploidy in extremotolerant fungi.
Topics: Ascomycota; Genomics; Hybridization, Genetic; Inbreeding; Phylogeny; Yeasts
PubMed: 36200832
DOI: 10.1093/gigascience/giac095