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Journal of Fungi (Basel, Switzerland) Mar 2024Yeast infections are challenging human and animal medicine due to low rates of detection and the emergence of unknown ecology isolates. The aim of this study was to...
Yeast infections are challenging human and animal medicine due to low rates of detection and the emergence of unknown ecology isolates. The aim of this study was to verify the biochemical identification of yeasts and yeast-like microorganisms obtained from animals comparing the results with chromogenic media and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF MS). Between January and August 2023, yeast and yeast-like isolates from samples of animals with suspicion of mycosis were identified using Vitek 2 Compact, Brilliance Candida Agar and MALDI Biotyper MSP. A total of 39 cases were included, and 45 isolations were obtained. (15.5%, 7/45), (13.3%, 6/45), (11.1%, 5/45), and (8.9%, each one 4/45) were the most identified organisms. There was full agreement with the three identification methods in 71.1% (32/45) of the isolates, disagreement on species in 17.8% (8/45), disagreement on genus and species in 6.7% (3/45) and, in 4.4% (2/45), there was no matched pattern in MALDI-TOF to compare the results. Biochemical methods are a good option in laboratories where proteomics are not available, and chromogenic media enhances diagnostics by detecting mixed infections. Surveillance must be implemented to improve the detection of agents shared between humans and animals.
PubMed: 38535226
DOI: 10.3390/jof10030218 -
International Journal of Food... Jun 2024Previous investigations proved the potential of Saccharomyces cerevisiae MBELGA62 and Pichia kudriavzevii MBELGA61 as suitable biocontrolling agents against Aspergillus...
Previous investigations proved the potential of Saccharomyces cerevisiae MBELGA62 and Pichia kudriavzevii MBELGA61 as suitable biocontrolling agents against Aspergillus sp. through the production of soluble and volatile bioactive antifungal compounds. The present study delves into those finding by means of the identification of the volatile compounds produced by brewer's strains that demonstrated fungistatic and fungicidal effects against Aspergillus flavus and A. parasiticus when cultured in brewer's wort agar plates. Traditional brewer's yeasts such as S. cerevisiae MBELGA62 and Saccharomyces pastorianus SAFS235 synthetize volatiles that fully inhibited mycelial development for up to 9 days at 30 °C. The non-conventional brewer's strains P. kudriavzevii MBELGA61 and Meyerozyma guilliermondii MUS122 increased the lag phase by >100% and significantly reduced the fungal growth rate by 27.5-43.0% and 15.4-31.4%, respectively. In this context, 2-phenylethanol, 2-phenylethyl acetate and benzyl alcohol were identified as the main antifungal agents involved in Aspergillus sp.'s inhibition.
Topics: Aspergillus; Fermentation; Antifungal Agents; Volatile Organic Compounds; Saccharomyces cerevisiae; Pichia; Phenylethyl Alcohol
PubMed: 38640817
DOI: 10.1016/j.ijfoodmicro.2024.110692 -
Synthetic and Systems Biotechnology Mar 2024Dopamine can be used to treat depression, myocardial infarction, and other diseases. However, few reports are available on the de novo microbial synthesis of dopamine...
Dopamine can be used to treat depression, myocardial infarction, and other diseases. However, few reports are available on the de novo microbial synthesis of dopamine from low-cost substrate. In this study, integrated omics technology was used to explore the dopamine metabolism of a novel marine multi-stress-tolerant aromatic yeast GXDK6. GXDK6 was found to have the ability to biosynthesize dopamine when using glucose as the substrate. 14 key genes for the biosynthesis of dopamine were identified by whole genome-wide analysis. Transcriptomic and proteomic data showed that the expression levels of gene encoding aspartate aminotransferase (regulating dopamine anabolism) were upregulated, while gene encoding copper amine oxidase (involved in dopamine catabolism) were downregulated under 10 % NaCl stress compared with non-NaCl stress, thereby contributing to biosynthesis of dopamine. Further, the amount of dopamine under 10 % NaCl stress was 2.51-fold higher than that of zero NaCl, which was consistent with the multi-omics results. Real-time fluorescence quantitative PCR (RT-qPCR) and high-performance liquid chromatography (HPLC) results confirmed the metabolic model of dopamine. Furthermore, by overexpressing , AST enzyme activity was increased by 24.89 %, the expression of genes related to dopamine metabolism was enhanced, and dopamine production was increased by 56.36 % in recombinant GXDK6AAT2. In conclusion, GXDK6 could utilize low-cost carbon source to synthesize dopamine, and NaCl stress promoted the biosynthesis of dopamine.
PubMed: 38292761
DOI: 10.1016/j.synbio.2024.01.002 -
Ecotoxicology and Environmental Safety Sep 2023The presence of high salinity levels in textile wastewater poses a significant obstacle to the process of decolorizing azo dyes. The present study involved the...
The presence of high salinity levels in textile wastewater poses a significant obstacle to the process of decolorizing azo dyes. The present study involved the construction of a yeast consortium HYC, which is halotolerant and was recently isolated from wood-feeding termites. The consortium HYC was mainly comprised of Sterigmatomyces halophilus SSA-1575 and Meyerozyma guilliermondii SSA-1547. The developed consortium demonstrated a decolourization efficiency of 96.1% when exposed to a concentration of 50 mg/l of Reactive Black 5 (RB5). The HYC consortium significantly decolorized RB5 up to concentrations of 400 mg/l and in the presence of NaCl up to 50 g/l. The effects of physicochemical factors and the degradation pathway were systematically investigated. The optimal pH, salinity, temperature, and initial dye concentration were 7.0, 3%, 35 °C and 50 mg/l, respectively. The co-carbon source was found to be essential, and the addition of glucose resulted in a 93% decolorization of 50 mg/l RB5. The enzymatic activity of various oxido-reductases was assessed, revealing that NADH-DCIP reductase and azo reductase exhibited greater activity in comparison to other enzymes. UV-Visible (UV-vis) spectrophotometry, Fourier-transform infrared spectroscopy (FTIR), high-performance liquid chromatography (HPLC), and gas chromatography-mass spectrometry (GC-MS) were utilized to identify the metabolites generated during the degradation of RB5. Subsequently, a metabolic pathway was proposed. The confirmation of degradation was established through alterations in the functional groups and modifications in molecular weight. The findings indicate that this halotolerant yeast consortium exhibits promising potential of degrading dye compounds. The results of this study offer significant theoretical basis and crucial perspectives for the implementation of halotolerant yeast consortia in the bioremediation of textile and hypersaline wastewater. This approach is particularly noteworthy as it does not produce aromatic amines.
Topics: Azo Compounds; Wastewater; Gas Chromatography-Mass Spectrometry; Chromatography, High Pressure Liquid; Biodegradation, Environmental; Coloring Agents
PubMed: 37478569
DOI: 10.1016/j.ecoenv.2023.115258 -
Journal of Fungi (Basel, Switzerland) Sep 2023The use of the cationic, dye thioflavin T (ThT), to estimate the electric plasma membrane potential difference (PMP) via the fluorescence changes and to obtain its...
The use of the cationic, dye thioflavin T (ThT), to estimate the electric plasma membrane potential difference (PMP) via the fluorescence changes and to obtain its actual values from the accumulation of the dye, considering important correction factors by its binding to the internal components of the cell, was described previously for baker's yeast. However, it was considered important to explore whether the method developed could be applied to other yeast strains. Alternative ways to estimate the PMP by using flow cytometry and a multi-well plate reader are also presented here. The methods were tested with other strains of (W303-1A and FY833), as well as with non-conventional yeasts: , , , and . Results of the estimation of the PMP via the fluorescence changes under different conditions were adequate with all strains. Consistent results were also obtained with several mutants of the main monovalent transporters, validating ThT as a monitor for PMP estimation.
PubMed: 37755056
DOI: 10.3390/jof9090948 -
Plants (Basel, Switzerland) Nov 2023Phytoremediation, an environmentally friendly and sustainable approach for addressing Cu-contaminated environments, remains underutilized in mine tailings. Arbuscular...
Phytoremediation, an environmentally friendly and sustainable approach for addressing Cu-contaminated environments, remains underutilized in mine tailings. Arbuscular mycorrhizal fungi (AMF) play a vital role in reducing Cu levels in plants through various mechanisms, including glomalin stabilization, immobilization within fungal structures, and enhancing plant tolerance to oxidative stress. Yeasts also contribute to plant growth and metal tolerance by producing phytohormones, solubilizing phosphates, generating exopolysaccharides, and facilitating AMF colonization. This study aimed to assess the impact of AMF and yeast inoculation on the growth and antioxidant response of plants growing in Cu mine tailings amended with compost. Plants were either non-inoculated (NY) or inoculated with (MG), (RM), or a combination of both (MIX). Plants were also inoculated with (CC), while others remained non-AMF inoculated (NM). The results indicated significantly higher shoot biomass in the MG-NM treatment, showing a 3.4-fold increase compared to the NY-NM treatment. The MG-CC treatment exhibited the most substantial increase in root biomass, reaching 5-fold that in the NY-NM treatment. Co-inoculation of AMF and yeast influenced antioxidant activity, particularly catalase and ascorbate peroxidase. Furthermore, AMF and yeast inoculation individually led to a 2-fold decrease in total phenols in the roots. Yeast inoculation notably reduced non-enzymatic antioxidant activity in the ABTS and CUPRAC assays. Both AMF and yeast inoculation promoted the production of photosynthetic pigments, further emphasizing their importance in phytoremediation programs for mine tailings.
PubMed: 38068648
DOI: 10.3390/plants12234012 -
Foods (Basel, Switzerland) Apr 2024An amplicon metagenomic approach based on the ITS2 region of fungal rDNA was used to investigate the diversity of fungi associated with mature strawberries collected...
An amplicon metagenomic approach based on the ITS2 region of fungal rDNA was used to investigate the diversity of fungi associated with mature strawberries collected from a volcanic orchard and open-air market stands. Based on the Kruskal-Wallis test, no statistically significant differences were observed in both non-phylogenetic and phylogenetic alpha diversity indices. According to beta diversity analyses, significant differences in fungal communities were found between groups (orchard vs. market). Taxonomic assignment of amplicon sequence variables (ASVs) revealed 7 phyla and 31 classes. The prevalent fungal phyla were (29.59-84.58%), (15.33-70.40%), and Fungi-phy-Insertae-sedis (0.45-2.89%). The most predominant classes among the groups were in the market group, and and in the orchard group. Based on the analysis of microbiome composition (ANCOM), we found that the most differentially fungal genera were , , and Endophytic yeasts were prevalent in both groups, while was detected in fruits originating only from the market. In addition, (relative abundance varying from 1.7% to 21.18%) and (relative abundance varying from 1.58% to 16.55%) were detected in all samples regardless of origin, while was detected in samples from the market only, their relative abundance varying with the sample (from 0.80% to 19.23%). Their role in fruit quality and safety has not been yet documented. Moreover, several clinically related yeasts, such as and , were detected in samples only from the market. Understanding the variety and makeup of the mycobiome in ripe fruits during the transition from the orchard to the market is crucial for fruit safety after harvest.
PubMed: 38672848
DOI: 10.3390/foods13081175