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Molecular Biology of the Cell Apr 2024is a ubiquitous fungus with a wide variety of morphologies and growth modes including "typical" single-budding yeast, and interestingly, larger multinucleate yeast than...
is a ubiquitous fungus with a wide variety of morphologies and growth modes including "typical" single-budding yeast, and interestingly, larger multinucleate yeast than can make multiple buds in a single cell cycle. The study of promises to uncover novel cell biology, but currently tools are lacking to achieve this goal. Here, we describe initial components of a cell biology toolkit for , which is used to express and image fluorescent probes for nuclei as well as components of the cytoskeleton. These tools allowed live-cell imaging of the multinucleate and multibudding cycles, revealing highly synchronous mitoses in multinucleate yeast that occur in a semiopen manner with an intact but permeable nuclear envelope. These findings open the door to using this ubiquitous polyextremotolerant fungus as a model for evolutionary cell biology.
Topics: Saccharomyces cerevisiae; Ascomycota; Aureobasidium; Cytoskeleton
PubMed: 38446617
DOI: 10.1091/mbc.E23-10-0388 -
International Journal of Food... Apr 2024Alternaria alternata is a common fungal pathogen causing postharvest decay in table grapes. This study addressed the potential of autochthonous yeasts and bioactive...
Alternaria alternata is a common fungal pathogen causing postharvest decay in table grapes. This study addressed the potential of autochthonous yeasts and bioactive compounds of natural sources to act as biocontrol agents (BCAs) against A. alternata in cold-stored table grapes. With this purpose, 19 yeast capable of growing at 0-1 °C were isolated from the surface of Red Globe table grapes. These isolates, along with the pre-isolated strain Metschnikowia pulcherrima RCM2, were evaluated as BCAs in wounded berries. From these results, six yeast isolates were pre-selected to be combined with bioactive compounds of natural sources, like phenolic compounds (PCs) of side streams of wine industry, including bunch stem extract (BSE) (5-25 %), and cane extract (CE) (5-25 %), and functional polysaccharides from shrimp waste such as chitosan (CH) (0.5 %). Then, the biocontrol efficacy of combined treatments beyond individual ones was compared. The results revealed that 4 yeast isolates, namely M. pulcherrima RCM2 and ULA146, and Aureobasidium pullulans FUL14 and FUL18, were the most effective. However, when combined with the natural bioactive compounds, their efficacy against A. alternata did not increase significantly. Notably, ULA146 and FUL18 demonstrated a biocontrol efficacy of 36-37 %, comparable to that of the treatment with commercial doses of SO, which only showed a 27 % reduction in the lesion diameter. These findings highlight the potential of using psychrotrophic yeasts as BCAs against A. alternata in cold-stored table grapes. Combining these yeast strains with BSE, CE and CH did not increase BCAs efficacy against this pathogen at the concentrations tested. The development of effective biocontrol strategies for A. alternata could contribute to reducing reliance on chemically synthesized fungicides, promoting sustainable practices, aiming to improve the quality and safety of cold-stored table grapes.
Topics: Vitis; Yeasts; Alternaria; Fungicides, Industrial
PubMed: 38442539
DOI: 10.1016/j.ijfoodmicro.2024.110640 -
Journal of Bioscience and Bioengineering May 2024A high-yielding microbial polysaccharide-producing strain, named RM1603, was isolated from rhizosphere soil and identified by morphological and phylogenetic analysis....
A high-yielding microbial polysaccharide-producing strain, named RM1603, was isolated from rhizosphere soil and identified by morphological and phylogenetic analysis. The extracellular polysaccharides (EPS) were identified by thin-layer chromatography and infrared spectroscopy. The fermentation conditions were optimized by single factor experiments in shake flasks and a 5-L fermentor. The results of morphological and phylogenetic tree analysis showed that RM1603 was a strain of Aureobasidium pullulans. Its microbial polysaccharide was identified as pullulan, and the EPS production capacity reached 33.07 ± 1.03 g L in shake flasks. The fermentation conditions were optimized in a 5-L fermentor, and were found to encompass an initial pH of 6.5, aeration rate of 2 vvm, rotor speed of 600 rpm, and inoculum size of 2 %. Under these conditions, the pullulan yield of RM1603 reached 62.52 ± 0.24 g L. Thus, this study contributes RM1603 as a new isolation with high-yielding pullulan and potential application value in biotechnology.
Topics: Fermentation; Phylogeny; Ascomycota; Polysaccharides; Aureobasidium; Glucans
PubMed: 38413318
DOI: 10.1016/j.jbiosc.2023.12.018 -
Acta Myologica : Myopathies and... 2023Muscular dystrophies other than Duchenne muscular dystrophy (DMD) are genetic diseases characterized by increasing muscle weakness, loss of ambulation, and ultimately...
BACKGROUND
Muscular dystrophies other than Duchenne muscular dystrophy (DMD) are genetic diseases characterized by increasing muscle weakness, loss of ambulation, and ultimately cardiac and respiratory failure. There are currently no effective therapeutics available. Having demonstrated the efficacy of a N-163 strain of Aureobasidium Pullulans (Neu-REFIX) produced B-1, 3-1,6-Glucan in pre-clinical and clinical studies of Duchenne muscular dystrophy (DMD) earlier, we assessed the effectiveness of this novel Beta glucan in the other muscular dystrophies in the present study.
METHODS
In this 60-day study, six patients with muscular dystrophies other than DMD consumed one 8g gel of Neu-REFIX beta-glucan along with their usual standard of care treatment regimen, and their biomarkers of relevance to muscle function such as serum calcium (SC), creatine phosphokinase (CPK), and alkaline phosphatase (ALP) levels along with functional improvement criteria, which is, Medical research council (MRC) scale and North Star Ambulatory assessment (NSAA), assessed at baseline and following the intervention.
RESULTS
After the intervention, the SC levels significantly decreased from a mean baseline value of 9.28 mg/dL to 8.31 mg/dL (p-value = 0.02). With a p-value of 0.29, the mean CPK value dropped from 2192.33 IU/L to 1567.5 IU/L. Following the intervention, the ALP levels dropped from 200.33 to 75.5 U/L (p-value = 0.15). MRC scale improved in three out of six patients. NSAA remained stable. There were no adverse effects.
CONCLUSION
This study has proven the safety of Neu REFIX beta-glucan food supplement and its efficacy in improving both plasma biomarkers and functional parameters of muscle in a short duration of 2 months. Further validation by evaluation of muscle function for a longer duration is recommended to confirm the efficacy of Neu-REFIX food supplement as a potential adjuvant DMT in muscular dystrophies.
Topics: Humans; Muscular Dystrophy, Duchenne; beta-Glucans; Biomarkers; Muscles; Muscle Weakness
PubMed: 38406382
DOI: 10.36185/2532-1900-312 -
Biotechnology Journal Feb 2024Aureobasidium melanogenum was found to be grown the best at the constant pH 7.0 and to produce the highest amount of liamocins at the constant pH 3.0. Therefore, the...
Aureobasidium melanogenum was found to be grown the best at the constant pH 7.0 and to produce the highest amount of liamocins at the constant pH 3.0. Therefore, the wild type strain A. melanogenum 9-1 and the engineered strain V33 constructed in the laboratory were grown at the constant pH 7.0 for 48 h, then, they were continued to be cultivated at the constant pH 3.0. Under such conditions, A. melanogenum 9-1 produced 36.51 ± 0.55 g L of liamocin and its cell mass was 27.43 ± 0.63 and 6.00 ± 0.11 g L of glucose was left in the finished medium within 168 h while the engineered strain V33 secreted 70.86 ± 2.04 g L of liamocin, its cell mass was 31.63 ± 0.74 g L , 0.16 ± 0.01 g L of glucose was maintained in the finished medium. Then, Massoia lactone was released from the produced liamocins. The released Massoia lactone loaded in the nanoemulsions could be used to actively damage cell wall and cell membrane of both spores and mycelia of Aspergillus flavus, leading to its cell necrosis. Massoia lactone loaded in the nanoemulsions also actively inhibited cell growth of A. flavus, its conidia production and aflatoxin biosynthesis on peanuts, indicating that Massoia lactone loaded in the nanoemulsions had highly potential application in controlling cell growth of A. flavus and aflatoxin biosynthesis in foods and feedstuffs.
Topics: Aspergillus flavus; Fermentation; Lactones; Aflatoxins; Hydrogen-Ion Concentration; Glucose
PubMed: 38404053
DOI: 10.1002/biot.202300675 -
Microorganisms Feb 2024Post-harvest decay of fresh table grapes causes considerable annual production losses. The main fungal agents of decay both in pre- and post-harvest are , spp., spp.,...
Post-harvest decay of fresh table grapes causes considerable annual production losses. The main fungal agents of decay both in pre- and post-harvest are , spp., spp., spp., and spp. To date, the use of agrochemicals and SO are the main methods to control grape molds in pre- and postharvest, respectively. Significant improvements, however, have already been made in to apply innovative and more environmentally sustainable control strategies, such as Biological Control Agents (BCAs), which can reduce disease severity in both pre- and post-harvest. In this study, 31 new non- yeast strains, isolated from berries of native Apulian table grape genotypes, were tested for their in vivo effectiveness against grey mold of table grapes, resulting in two ('N22_I1' and 'S13_I3'), one ('N22_I3'), one ('OLB_9.1_VL') and one ('OLB_9.1_BR') yeast strains that were marked as efficient and good BCAs. Their mechanisms of action were characterized through in vitro assays, and additional characteristics were evaluated to assess the economic feasibility and viability for future technological employment. Their effectiveness was tested by reducing the working concentration, their antagonistic effect on a wide range of fungal pathogens, their ability to survive in formulations with long shelf life, and their safety to human health.
PubMed: 38399744
DOI: 10.3390/microorganisms12020340 -
Toxins Feb 2024Different preventive strategies are needed to minimize the intake risks of mycotoxins, including zearalenone (ZEN). The aim of this study was to determine the ZEN...
Different preventive strategies are needed to minimize the intake risks of mycotoxins, including zearalenone (ZEN). The aim of this study was to determine the ZEN adsorption ability of an autolyzed biomass preparation of polymorphic yeast A.p.-3. The evaluation of the antitoxic properties of the preparation was also performed in relation to yeast (ATCC 2366, ATCC 7090 and ATCC 9763) used as a model cell exposed to a toxic ZEN dose. The preparation at a dose of 5 mg/mL showed the adsorption of ZEN present in model systems at concentrations between 1 μg/mL to 100 μg/mL. The highest degree of adsorption was established for ZEN concentrations of 1 μg/mL and 5 μg/mL, becoming limited at higher doses of the toxin. Based on the Langmuir model of adsorption isotherms, the predicted maximum ZEN adsorption was approx. 190 µg/mL, regardless of pH. The growth of three strains of yeast cells in the medium with ZEN at concentrations within the range of 1.56 μg/mL-100 μg/mL was analyzed to determine the minimum inhibitory concentration. The growth of all tested strains was especially limited by high doses of ZEN, i.e., 50 and 100 μg/mL. The protective effect of the tested preparation was noted in relation to yeast cells exposed to toxic 100 μg/mL ZEN doses. The highest yeast cell growth (app. 36% percentage) was noted for a ATCC 9763 strain compared to the medium with ZEN but without preparation. More detailed tests determining the antitoxic mechanisms of the preparation are planned in the future, including cell culture bioassays and animal digestive tract models.
Topics: Animals; Zearalenone; Saccharomyces cerevisiae; Adsorption; Biomass; Aureobasidium
PubMed: 38393183
DOI: 10.3390/toxins16020105 -
Journal of Fungi (Basel, Switzerland) Feb 2024Verticillium wilt of olive (VWO) caused by is considered a major olive () disease in Mediterranean-type climate regions. The lack of effective chemical products against...
Verticillium wilt of olive (VWO) caused by is considered a major olive () disease in Mediterranean-type climate regions. The lack of effective chemical products against VWO makes it necessary to search for alternatives such as biological control. The main goal of this study was to evaluate the effect of six spp. strains as biological control agents (BCAs) against VWO. All of them were molecularly characterized by sequencing 16S or 23S rRNA genes and via phylogenetic analysis. Their effect was evaluated in vitro on the mycelial growth of (isolates V004 and V323) and on microsclerotia (MS) viability using naturally infested soils. Bioassays in olive plants inoculated with were also conducted to evaluate their effect against disease progress. In all the experiments, the reference BCAs FO12 and AP08 were included for comparative purposes. The six strains were identified as spp., and they were considered as potential new species. All the BCAs, including strains, showed a significant effect on mycelial growth inhibition for both isolates compared to the positive control, with FO12 being the most effective, followed by AP08, while the spp. strains showed an intermediate effect. All the BCAs tested also showed a significant effect on the inhibition of germination of MS compared to the untreated control, with FO12 being the most effective treatment. Irrigation treatments with strain CBQ-EBa-21 or FO12 were significantly more effective in reducing disease severity and disease progress in olive plants inoculated with compared to the remaining treatments. This study represents the first approach to elucidating the potential effect of strains against VWO.
PubMed: 38392810
DOI: 10.3390/jof10020138 -
Microbiology Resource Announcements Mar 2024The yeast strain W12 was isolated from an aircraft polymer-coated surface. The genome size is 53,160,883 bp with a G + C content of 50.13%. The genome contains fatty...
The yeast strain W12 was isolated from an aircraft polymer-coated surface. The genome size is 53,160,883 bp with a G + C content of 50.13%. The genome contains fatty acid transporters, cutinases, hydroxylases, and lipases potentially used for survival on polymer coatings on aircraft.
PubMed: 38376194
DOI: 10.1128/mra.00756-23 -
Applied Microbiology and Biotechnology Feb 2024Aureobasidium is omnipresent and can be isolated from air, water bodies, soil, wood, and other plant materials, as well as inorganic materials such as rocks and marble.... (Review)
Review
Aureobasidium is omnipresent and can be isolated from air, water bodies, soil, wood, and other plant materials, as well as inorganic materials such as rocks and marble. A total of 32 species of this fungal genus have been identified at the level of DNA, of which Aureobasidium pullulans is best known. Aureobasidium is of interest for a sustainable economy because it can be used to produce a wide variety of compounds, including enzymes, polysaccharides, and biosurfactants. Moreover, it can be used to promote plant growth and protect wood and crops. To this end, Aureobasidium cells adhere to wood or plants by producing extracellular polysaccharides, thereby forming a biofilm. This biofilm provides a sustainable alternative to petrol-based coatings and toxic chemicals. This and the fact that Aureobasidium biofilms have the potential of self-repair make them a potential engineered living material avant la lettre. KEY POINTS: •Aureobasidium produces products of interest to the industry •Aureobasidium can stimulate plant growth and protect crops •Biofinish of A. pullulans is a sustainable alternative to petrol-based coatings •Aureobasidium biofilms have the potential to function as engineered living materials.
Topics: Aureobasidium; Biofilms; Calcium Carbonate; Crops, Agricultural; Gasoline
PubMed: 38349550
DOI: 10.1007/s00253-024-13025-5