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Microbial Pathogenesis Mar 2023Meyerozyma guilliermondii is a rare opportunistic fungal pathogen that causes deadly invasive candidiasis in human. M. guilliermondii strain SO is a local yeast isolate...
Enolase in Meyerozyma guilliermondii strain SO: Sequential and structural insights of MgEno4581 as a putative virulence factor and host-fungal interactions through comprehensive in silico approaches.
Meyerozyma guilliermondii is a rare opportunistic fungal pathogen that causes deadly invasive candidiasis in human. M. guilliermondii strain SO is a local yeast isolate that possesses huge industrial interests but also pathogenic towards zebrafish embryos. Enolases that bind to human extracellular matrix (ECM) proteins are among the fungal virulence factors. To understand its pathogenicity mechanism down to molecular level, especially in the rare M. guilliermondii, this study aimed to identify and characterize the potentially virulence-associated enolase in M. guilliermondii strain SO using bioinformatics approaches. Profile Hidden-Markov model was implemented to identify enolase-related sequences in the fungal proteome. Sequence analysis deciphered only one (MgEno4581) out of nine sequences exhibited potent virulence traits observed similarly in the pathogenic Candida albicans. MgEno4581 structure that was predicted via SWISS-MODEL using C. albicans enolase (CaEno1; PDB ID: 7vrd) as the homology modeling template portrayed a highly identical motif with CaEno1 that facilitates ECM proteins binding. Amino acid substitutions (D234K, K235A, Y238H, K239D, G243K, V248C and Y254F) in ECM-binding motif of Saccharomyces cerevisiae enolase (ScEno) compared to MgEno4581 and CaEno1 caused changes in motif's surface charges. Protein-protein docking indicated F253 in ScEno only interacted hydrophobically with human plasminogen (HPG). Hydrogen linkages were observed for both MgEno4581 and CaEno1, suggesting a stronger interaction with HPG in the hydrophilic host microenvironments. Thus, our in silico characterizations on MgEno4581 provided new perspectives on its potential roles in candidiasis (fungal-host interactions) caused by M. guilliermondii, especially M. guilliermondii strain SO on zebrafish embryos that mimic the immunocompromised individuals as previously evident.
Topics: Animals; Humans; Virulence Factors; Zebrafish; Phosphopyruvate Hydratase; Host Microbial Interactions; Candida albicans
PubMed: 36754101
DOI: 10.1016/j.micpath.2023.106025 -
Molecules (Basel, Switzerland) Oct 2019Onychomycosis is a major health problem due to its chronicity and resistance to therapy. Because some cases associate paronychia, any therapy must target the fungus and...
Onychomycosis is a major health problem due to its chronicity and resistance to therapy. Because some cases associate paronychia, any therapy must target the fungus and the inflammation. Medicinal plants represent an alternative for onychomycosis control. In the present work the antifungal and antioxidant activities of extract against (Wick.) Kurtzman & M. Suzuki and (A. Jörg.) F.C. Harrison, isolated for the first time from a toenail onychomycosis case, were investigated. The fungal species were confirmed by DNA molecular analysis. minimum inhibitory concentration (MIC) and ultrastructural effects were examined. At the MIC concentration (120 mg/mL) the micrographs indicated severe structural alterations with cell death. The antioxidant properties of the extract were evaluated is a rat turpentine oil induced inflammation, and compared to an anti-inflammatory drug, diclofenac, and the main compound from the extract, allicin. reduced serum total oxidative status, malondialdehyde and nitric oxide production, and increased total thiols. The effects were comparable to those of allicin and diclofenac. In conclusion, the garlic extract had antifungal effects against and , and antioxidant effect in turpentine-induced inflammation. Together, the antifungal and antioxidant activities support that is a potential alternative treatment in onychomycosis.
Topics: Animals; Antifungal Agents; Antioxidants; Benzothiazoles; Biphenyl Compounds; Colony Count, Microbial; Free Radical Scavengers; Garlic; Humans; Male; Nails; Onychomycosis; Phytochemicals; Picrates; Plant Extracts; Rats, Wistar; Rhodotorula; Saccharomycetales; Sulfonic Acids
PubMed: 31683743
DOI: 10.3390/molecules24213958 -
G3 (Bethesda, Md.) Mar 2018Yeasts of the species complex are widespread in nature and can be isolated from a variety of sources, from the environment to arthropods to hospital patients. To date,...
Yeasts of the species complex are widespread in nature and can be isolated from a variety of sources, from the environment to arthropods to hospital patients. To date, the species complex comprises the thoroughly studied and versatile , the hard to distinguish , and Here we report the whole genome sequencing and assembly of four isolates, identified with the most recent molecular techniques, derived from four Diptera species. The four novel assemblies present reduced fragmentation and comparable metrics (genome size, gene content) to the available genomes belonging to the species complex. We performed a phylogenomic analysis comprising all known members of the species complex, to investigate evolutionary relationships within this clade. Our results show a compact phylogenetic structure for the complex and indicate the presence of a sizable core set of genes. Furthermore, , despite a broad literature on the difficulties of discerning it from , seems to be more closely related to Finally, we believe that there is evidence for considering these four genomes to be the first published for the species Raw reads and assembled contigs have been made public to further the study of these organisms.
Topics: Ascomycota; Computational Biology; Genome, Fungal; Genomics; Molecular Sequence Annotation; Phylogeny
PubMed: 29311113
DOI: 10.1534/g3.117.300316 -
Molecules (Basel, Switzerland) Oct 2023Using YB4, which was isolated and screened from southern Sichuan pickles in the laboratory, as the experimental group, we investigated the changes in growth, total...
Using YB4, which was isolated and screened from southern Sichuan pickles in the laboratory, as the experimental group, we investigated the changes in growth, total ester content, and volatile flavor substances of YB4 under different NaCl concentrations. The growth of YB4 was found to be inhibited by NaCl, and the degree of inhibition increased at higher NaCl concentrations. Additionally, the total ester content of the control group (CK) was significantly lower compared to the other groups ( < 0.05). The application of NaCl also resulted in distinct changes in the volatile profile of YB4, as evidenced by E-nose results. Gas chromatography-mass spectrometry (GC-MS) and gas chromatography-ion mobility spectrometry (GC-IMS) were employed to analyze the volatile compounds. A total of 148 and 86 volatiles were detected and identified using GC-MS and GC-IMS, respectively. Differential volatiles among the various NaCl concentrations in YB4 were determined by a variable importance in projection (VIP) analysis in partial least squares-discriminant analysis (PLS-DA). These differentially expressed volatiles were further confirmed by their relative odor activity value (ROAV) and odor description. Ten key contributing volatiles were identified, including ethanol, 1-pentanol, nonanal, octanal, isoamyl acetate, palmitic acid ethyl ester, acrolein, ethyl isobutanoate, prop-1-ene-3,3'-thiobis, and 2-acetylpyrazine. This study provides insights into the specificities and contributions of volatiles in YB4 under different NaCl concentrations. These findings offer valuable information for the development of aroma-producing yeast agents and the subsequent enhancement in the flavor of southern Sichuan pickles.
Topics: Gas Chromatography-Mass Spectrometry; Electronic Nose; Sodium Chloride; Volatile Organic Compounds; Odorants; Esters
PubMed: 37836821
DOI: 10.3390/molecules28196979 -
Microbial Cell Factories Jan 2021Nerol (CHO), an acyclic monoterpene, naturally presents in plant essential oils, and is used widely in food, cosmetics and pharmaceuticals as the valuable fragrance....
BACKGROUND
Nerol (CHO), an acyclic monoterpene, naturally presents in plant essential oils, and is used widely in food, cosmetics and pharmaceuticals as the valuable fragrance. Meanwhile, chemical synthesis is the only strategy for large-scale production of nerol, and the disadvantages of chemical synthesis greatly limit the production and its application. These defects drive the interests of researchers shift to the production of nerol by eco-friendly methods known as biosynthesis methods. However, the main technical bottleneck restricting the biosynthesis of nerol is the lacking of corresponding natural aroma-producing microorganisms.
RESULTS
In this study, a novel multi-stress-tolerant probiotics Meyerozyma guilliermondii GXDK6 with aroma-producing properties was identified by whole genome sequencing and metabolomics technology. GXDK6 showed a broad pH tolerance in the range of 2.5-10.0. The species also showed salt tolerance with up to 12% NaCl and up to 18% of KCl or MgCl. GXDK6 exhibited heavy-metal Mn tolerance of up to 5494 ppm. GXDK6 could also ferment with a total of 21 kinds of single organic matter as the carbon source, and produce abundant aromatic metabolites. Results from the gas chromatography-mass spectrometry indicated the production of 8-14 types of aromatic metabolites (isopentanol, nerol, geraniol, phenylethanol, isobutanol, etc.) when GXDK6 was fermented up to 72 h with glucose, sucrose, fructose, or xylose as the single carbon source. Among them, nerol was found to be a novel aromatic metabolite from GXDK6 fermentation, and its biosynthesis mechanism had also been further revealed.
CONCLUSION
A novel aroma-producing M. guilliermondii GXDK6 was identified successfully by whole genome sequencing and metabolomics technology. GXDK6 showed high multi-stress-tolerant properties with acid-base, salty, and heavy-metal environments. The aroma-producing mechanism of nerol in GXDK6 had also been revealed. These findings indicated the aroma-producing M. guilliermondii GXDK6 with multi-stress-tolerant properties has great potential value in the fermentation industry.
Topics: Acyclic Monoterpenes; Fungal Proteins; Genome, Fungal; Metabolome; Saccharomycetales; Stress, Physiological; Whole Genome Sequencing
PubMed: 33413399
DOI: 10.1186/s12934-020-01490-2 -
International Microbiology : the... May 2020Production of xylitol from lignocellulosic biomass is of interest to modern biorefineries, because this biomass should be processed into a spectrum of chemicals...
Production of xylitol from lignocellulosic biomass is of interest to modern biorefineries, because this biomass should be processed into a spectrum of chemicals (bio-based products) and not only energy. The isolation of new yeast strains capable of efficiently converting xylose into xylitol and withstanding inhibitors released from biomass hydrolysis can contribute to making its production feasible in biorefineries. Forty-three out of 128 yeast strains isolated from the gut of Passalidae beetles were capable of assimilating xylose as the sole carbon source. Meyerozyma guilliermondii UFV-1 was selected due to its ability to grow and ferment D-xylose in a synthetic medium. This yeast assimilated the broad range of sugars present in lignocellulosic biomass hydrolysates, such as xylose, raffinose, cellobiose, rhamnose, arabinose, and glucose. Its optimum growth conditions were pH 8.0 and a temperature of 30 °C. In concentrations of 0.07 mol/L acetic acid, 0.05 mol/L 5-hydroximethylfurfural, and 0.04 mol/L furfural, M. guilliermondii UFV-1 did not grow. Maximum xylitol production in aerobiosis and hypoxia were 51.88 and 27.73 g/L, respectively. Under aerobic condition, xylose concentration and agitation rate were the factors which were statistically significant, while only the agitation rate was significant in hypoxia. We fitted a response surface (RS) that estimated the best agitation rate (113.33 rpm) and xylose concentration (90 g/L) for maximum xylitol production in aerobiosis. Therefore, M. guilliermondii UFV-1 displays potential for being used for xylitol production in biorefineries.
Topics: Bioreactors; Fermentation; Lignin; Xylitol; Xylose; Yeasts
PubMed: 31813072
DOI: 10.1007/s10123-019-00105-0 -
Environmental Science and Pollution... Oct 2018Due to their renewable and sustainable nature, biodiesel blends boost studies predicting their stability during storage. Besides chemical degradation, biodiesel is more...
Due to their renewable and sustainable nature, biodiesel blends boost studies predicting their stability during storage. Besides chemical degradation, biodiesel is more susceptible to biodegradation due to its raw composition. The aim of this work was to evaluate the deteriogenic potential (growth and degradation) of Pseudallescheria boydii and Meyerozyma guilliermondii in degrading pure diesel (B0), pure biodiesel (B100), and a B10 blend in mineral medium during storage. The biodeterioration susceptibility at different fuel ratios and in BH minimal mineral medium were evaluated. The biomass measurements of P. boydii during 45 days indicated higher biomass production in the B10 blend. The growth curve of M. guilliermondii showed similar growth in B10 and B100. Although there was no significant production of biosurfactant, lipase production was detected in the tributyrin agar medium of both microorganisms. The main compounds identified in the aqueous phase by GC-MS were alcohols, esters, acids, sulfur, ketones, and phenols. The results showed that P. boydii grew at the expense of fuels, degrading biodiesel esters, and diesel hydrocarbons. M. guilliermondii grew in B100 and B10; however, degradation was not detected.
Topics: Ascomycota; Biofuels; Biomass; Brazil; Gasoline; Time Factors
PubMed: 30159846
DOI: 10.1007/s11356-018-3015-x -
Journal of Biomolecular Structure &... Jan 2024is a rare yeast pathogen contributing to the deadly invasive candidiasis. strain SO, as a promising protein expression host, showed 99% proteome similarity with the...
is a rare yeast pathogen contributing to the deadly invasive candidiasis. strain SO, as a promising protein expression host, showed 99% proteome similarity with the clinically isolated ATCC 6260 (type strain) in a recent comparative genomic analysis. However, their virulence features and pathogenicity were uncharacterized. This study aimed to characterize the and pathogenicity of strain SO and analyze its Als proteins (Als) comprehensive bioinformatics approaches. strain SO showed lower and higher sensitivity towards β-mercaptoethanol and lithium, respectively than the avirulent but exhibited the same tolerance towards cell wall-perturbing Congo Red with . With 7.5× higher biofilm mass, strain SO also demonstrated 75% higher mortality rate in the zebrafish embryos with a thicker biofilm layer on the chorion compared to the avirulent . Being one of the most important adhesins, sequence and structural analyses of four statistically identified Als showed that Als1056 was predicted to exhibit the most conserved amyloid-forming regions, tandem repeat domain and peptide binding cavity (PBC) compared to Als3. Favoured from the predicted largest ligand binding site and druggable pockets, it showed the highest affinity towards hepta-threonine. Non-PBC druggable pockets in the most potent virulence contributing Als1056 provide new insights into developing antifungal drugs targeting non- spp. Virtual screening of available synthetic or natural bioactive compounds and Als1056 deletion from the fungal genome should be further performed and validated experimentally.Communicated by Ramaswamy H. Sarma.
PubMed: 38189364
DOI: 10.1080/07391102.2023.2300757 -
Food Microbiology Jun 2015Meyerozyma guilliermondii is a yeast species widely isolated from several natural environments and from fruit; in medical microbiology it is known as the teleomorph of...
Meyerozyma guilliermondii is a yeast species widely isolated from several natural environments and from fruit; in medical microbiology it is known as the teleomorph of the opportunistic pathogen Candida guilliermondii, which causes about 2% of the human blood infections. This yeast is also promising in a variety of biotechnological applications as vitamins production and post-harvest control. The question if isolates from different sources are physiologically and genetically similar, or if the various environments induced significant differences, is crucial for the understanding of this species structure and to select strains appropriate for each application. This question was addressed using LSU and ITS sequencing for taxonomic assignment, i-SSR (GACA4) for the molecular characterization and FTIR for the metabolomic fingerprint. All data showed that fruit and environmental isolates cluster separately with a general good agreement between metabolomics and molecular analysis. An additional RAPD analysis was able to discriminate strains according to the isolation position within the pineapple fruit. Although all strains are members of the M. guilliermondii species according to the current standards, the distribution of large variability detected suggests that some specialization occurred in the niches inhabited by this yeast and that food related strains can be differentiated from the medical isolates.
Topics: Environmental Microbiology; Food Microbiology; Genetic Variation; Humans; Mycoses; Phenotype; Phylogeny; Random Amplified Polymorphic DNA Technique; Saccharomycetales
PubMed: 25791010
DOI: 10.1016/j.fm.2014.12.014 -
Yeast (Chichester, England) Sep 2020Epiphytic yeasts were isolated from different cultivars of apples and lemons and identified by a combination of PCR-RFLP of 5.8S rRNA region and sequencing of D1/D2...
Biocontrol ability and action mechanisms of Aureobasidium pullulans GE17 and Meyerozyma guilliermondii KL3 against Penicillium digitatum DSM2750 and Penicillium expansum DSM62841 causing postharvest diseases.
Epiphytic yeasts were isolated from different cultivars of apples and lemons and identified by a combination of PCR-RFLP of 5.8S rRNA region and sequencing of D1/D2 domain of the 26S rRNA gene. Among 69 isolates, Aureobasidium pullulans GE17 and Meyerozyma guilliermondii KL3 strains showed the greatest antagonistic activity against two significant apple and lemon postharvest pathogens, Penicillium expansum DSM62841 (blue mold) and Penicillium digitatum DSM2750 (green mold), after preliminary screening. Yeasts were applied as single and mixed cultures with two different cell concentrations of 10 and 10 cells/ml in the present study. It was determined that antagonistic activity of two yeast strains studied emerged with a combination of several mechanisms of action including competition for space and nutrients, production of volatile organic compounds (VOCs), secretion of extracellular lytic enzymes and inhibition of fungal spore germination. The highest inhibition of mycelial growth on P. expansum DSM62841 and P. digitatum DSM2750 (83.4% and 74.7%, respectively) was achieved by utilization of single culture of A. pullulans GE17. Otherwise, the application of mixed culture at the ratio of 10 cells/ml inhibited spore germination of both pathogens from 86% to 95%. Results of this study suggest that an increase in yeast cell concentrations positively affected their biocontrol activity against blue and green molds. According to the results, employing single culture of M. guilliermondii KL3 did not exhibit effective antagonistic activity against blue and green molds. However, utilization of A. pullulans GE17 alone and mixed culture showed succesfull controlling against both P. expansum DSM62841 and P. digitatum DSM2750.
Topics: Antibiosis; Aureobasidium; Biological Control Agents; Citrus; Fruit; Malus; Penicillium; Saccharomycetales; Spores, Fungal
PubMed: 32452099
DOI: 10.1002/yea.3501