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European Journal of Clinical... Mar 2021In recent years, the frequency of infections due to saprophytic fungi has increased. Cryptococcus laurentii, recently classified as Papiliotrema laurentii, is...
In recent years, the frequency of infections due to saprophytic fungi has increased. Cryptococcus laurentii, recently classified as Papiliotrema laurentii, is responsible for fungemia, meningitis, and superficial infections. Here, we report the first case of cutaneous Papiliotrema (Cryptococcus) laurentii infection in a 23-year-old Caucasian woman affected by an autoimmune thyroiditis with hypothyroidism. Impairments of the immune system are often associated with unusual fungal infections, which cannot be neglected. The isolate strain was susceptible to Amphotericin B while resistant to fluconazole, itraconazole, voriconazole, and terbinafine. The patient was successfully treated with Amphotericin B.
Topics: Antifungal Agents; Basidiomycota; Dermatomycoses; Drug Resistance, Multiple, Fungal; Female; Humans; Hypothyroidism; Thyroiditis, Autoimmune; Treatment Outcome; Young Adult
PubMed: 33025101
DOI: 10.1007/s10096-020-04058-5 -
Journal of Medical Microbiology Nov 2020, formerly , is typically isolated from environmental sources, but also occasionally from clinical specimens. Other close relatives may be misidentified as by... (Comparative Study)
Comparative Study
, formerly , is typically isolated from environmental sources, but also occasionally from clinical specimens. Other close relatives may be misidentified as by phenotypic methods. usually lacks melanin; however, melanin-forming strains have also been isolated. Although melanin production by encapsulated budding yeasts is considered a major virulence factor, the comparative pathogenicity of melanin-forming and non-melanized environmental strains of has rarely been studied. We performed phenotypic and molecular identification and determined the genotypic heterogeneity among isolates. We also studied the pathogenicity of melanin-forming and non-melanized strains in normal and immunosuppressed mice. Eleven environmental isolates were tested for their identity by Vitek2 and/or ID32C systems, and by PCR-sequencing of the internal transcribed spacer (ITS) region and D1/D2 domains of ribosomal DNA (rDNA). Genotypic heterogeneity was studied by sequence comparisons. The pathogenicity of melanized and non-melanized strains was studied in intravenously infected normal and immunosuppressed BALB/c mice. Phenotypic methods identified seven of the environmental isolates, while PCR-sequencing of the ITS region and D1/D2 domains of rDNA detected two and five isolates, respectively, as . Sequence comparisons demonstrated genotypic heterogeneity among . The remaining four environmental isolates yielded expected results. None of the normal mice infected with 10 cells of melanized/non-melanized strains died. Infection of immunosuppressed mice with 10 cells caused higher mortality with non-melanized , while viable counts in brain/lung tissue were higher in mice infected with a melanized strain and were detectable for up to 14 days. Phenotypic methods lacked specificity, but PCR-sequencing of D1/D2 domains correctly identified and sequence comparisons demonstrated the genotypic heterogeneity of the isolates. Both melanized and non-melanized strains at a higher dose caused mortality in immunosuppressed mice and persisted in brain/lung tissue up to 14 days post-infection.
Topics: Animals; Basidiomycota; DNA, Fungal; DNA, Intergenic; Environmental Microbiology; Female; Genetic Variation; Genotype; Immunocompromised Host; Melanins; Mice; Mice, Inbred BALB C; Mycological Typing Techniques; Mycoses; Phylogeny; Sequence Analysis, DNA; Virulence; Virulence Factors
PubMed: 32945764
DOI: 10.1099/jmm.0.001254 -
Fungal Genetics and Biology : FG & B Nov 2020Oleaginous yeasts have stood out due to their ability to accumulate oil, which can be used for fatty acid-derived biofuel production. Papiliotrema laurentii UFV-1 is...
Oleaginous yeasts have stood out due to their ability to accumulate oil, which can be used for fatty acid-derived biofuel production. Papiliotrema laurentii UFV-1 is capable of starting the lipid accumulation in the late exponential growth phase and achieves maximum lipid content at 48 h of growth; it is, therefore, interesting to study how its oleaginous phenotype is regulated. Herein, we provide for the first time insights into the regulation of this phenotype in P. laurentii UFV-1. We sequenced and assembled its genome, performed comparative genomic analyses and investigated its phylogenetic relationships with other yeasts. Gene expression and metabolomic analyses were carried out on the P. laurentii UFV-1 cultivated under a nitrogen-limiting condition. Our results indicated that the lipogenesis of P. laurentii might have taken place during evolution after the divergence of genera in the phylum Basidiomycota. Metabolomic data indicated the redirection of the carbon flux towards fatty acid synthesis in response to the nitrogen limitation. Furthermore, purine seems to be catabolized to recycle nitrogen and leucine catabolization may provide acetyl-CoA for fatty acid synthesis. Analyses of the expression of genes encoding certain enzymes involved with the oleaginous phenotype indicated that the NADP-dependent malic enzyme seems to play an important role in the supply of NADPH for fatty acid synthesis. There was a surprising decrease in the expression of the ACC1 gene, which encodes acetyl-CoA carboxylase, during lipid accumulation. Taken together, our results provided a basis for understanding lipid accumulation in P. laurentii under nitrogen limiting conditions.
Topics: Basidiomycota; Fatty Acids; Gene Expression Regulation, Fungal; Lipid Metabolism; Lipids; Nitrogen; Phenotype; Phylogeny
PubMed: 32911061
DOI: 10.1016/j.fgb.2020.103456 -
3 Biotech Sep 2020In this work, we isolated and selected oleaginous yeasts from rock field soils from two National Parks in Brazil ( and ) with the potential to accumulate oil from...
In this work, we isolated and selected oleaginous yeasts from rock field soils from two National Parks in Brazil ( and ) with the potential to accumulate oil from xylose, the main pentose sugar found in lignocellulosic biomass. From the 126 isolates, two were selected based on their lipid contents. They were taxonomically identified as (UFV-1 and UFV-2). Of the two, UFV-1 was selected as the best lipid producer Under unoptimized conditions, lipid production by UFV-1 was higher in glucose than in xylose. To improve its lipid production from xylose, we applied response surface methodology (RSM) with a face-centered central composite design (CCF). We evaluated the effects of agitation rate, initial cell biomass (OD), carbon/nitrogen ratio (/ ratio) and pH on lipid production. UFV-1 recorded the highest lipid content, 63.5% (w/w) of the cell dry mass, under the following conditions: / ratio = 100:1, pH value = 7.0, initial OD = 0.8 and agitation = 300 rpm. Under these optimized conditions, biomass, lipid titer and volumetric lipid productivity were 9.31 g/L, 5.90 g/L and 0.082 g/L.h, respectively. Additionally, we determined the fatty acid composition of UFV-1 as follows: C14:0 (0.5%), C16:0 (28.4-29.4%), C16:1 (0.2%), C18:0 (9.5-11%), C18:1 (58.6-60.5%), and C20:0 (0.7-0.8%). Based on this composition, the predicted properties of biodiesel showed that UFV-1 oil is suitable for use as feedstock in biodiesel production.
PubMed: 32802724
DOI: 10.1007/s13205-020-02373-4 -
Microorganisms Aug 2020Some soil microorganisms, especially bacteria and mycorrhizal fungi, play a role in the promotion of plant growth. However, plant growth promotion involving yeasts in...
Some soil microorganisms, especially bacteria and mycorrhizal fungi, play a role in the promotion of plant growth. However, plant growth promotion involving yeasts in soil has not yet been extensively investigated. This study aimed to isolate and identify yeast strains obtained from soils of the Assam tea plant ( var. ) in northern Thailand and to investigate their plant growth promoting capabilities. A total of 42 yeast strains were obtained and identified by analysis of the D1/D2 domain of the large subunit ribosomal RNA gene. We identified 35 strains of six species belonging to the phylum Ascomycota, namely , , and and six species were determined to belong to the phylum Basidiomycota, namely , , , and . Seven strains were representative of potential new species and belonged to the genera Galactomyces and Wickerhamomyces. A total of 28 strains were found to produce indole-3-acetic acid (IAA) in a range of 2.12 to 37.32 mg/L, with the highest amount of IAA produced by . SDBR-CMU-S1-03. All yeast strains were positive in terms of ammonia production, and only eight strains were positive for siderophore production. Two yeast species, and , were able to solubilize the insoluble form of calcium and zinc. The ability to produce amylase, endogulcanase, lipase, pectinase, protease and xylanase was dependent upon the yeast species and strain involved.
PubMed: 32752164
DOI: 10.3390/microorganisms8081168 -
Brazilian Journal of Microbiology :... Sep 2020Ephemeral microbial communities usually undergo priority effect and result in higher diversity with a few representatives of each species. Community structure of yeasts...
Ephemeral microbial communities usually undergo priority effect and result in higher diversity with a few representatives of each species. Community structure of yeasts in bromeliad tanks was compared between two rupestrian savanna (Cerrado) areas in Brazil and to yeasts isolated from water holes in the same areas. Water samples were collected from 60 tanks of bromeliads Bromelia karatas and Encholirium sp. and rock holes at the Karstic Area of Aurora, Tocantins State and 60 tanks of Vriesea minarum (Bromeliaceae) and Paepalanthus bromelioides (Eriocaulaceae) at Serra do Cipó National Park, Minas Gerais State in Brazil. The yeast diversity comprised 90 species from which 60% are basidiomycetous yeasts usually associated with phylloplane, soils, and aquatic habitats. The species Papiliotrema laurentii, Rhodotorula mucilaginosa, Pa. nemorosus, and Pseudozyma hubeiensis were the most frequent species associated with bromeliads. Eighteen yeast species, two ascomycetous and 16 basidiomycetous, were consistently isolated from the substrates in both areas and may represent a core community in bromeliads in rupestrian fields. Singlets occurred in 38 to 69% of samples, and 32 species were isolated only once. Our findings reinforce the ephemeral nature of the yeast communities associated with tank-forming plants in which individual phytotelmata act as patches or aquatic islands prone to rapid colonization-extinction rates receiving inocula from plant and soil debris. Ephemeral rock holes also represent a transitory habitat for yeast species associated with plants and soil.
Topics: Biodiversity; Brazil; Bromeliaceae; Ecosystem; Eriocaulaceae; Mycobiome; Phylogeny; Soil Microbiology; Yeasts
PubMed: 32385836
DOI: 10.1007/s42770-020-00286-1 -
Applied Microbiology and Biotechnology May 2020Orange peel waste (OPW), the primary byproduct of the juice extraction process, is annually generated in massive amounts (21 Mton), and its aqueous extraction in...
Orange peel waste (OPW), the primary byproduct of the juice extraction process, is annually generated in massive amounts (21 Mton), and its aqueous extraction in biorefining operations yields a liquid fraction, referred to as orange peel extract (OPE). Although OPE contains significant amounts of easily assimilable carbohydrates, such as fructose, glucose, and sucrose, no investigations have been conducted yet to assess its possible use in biodiesel production by oleaginous yeasts. Consequently, the objective of the present study was to assess whether OPE might act as the basis of a liquid medium for microbial lipid production. A screening conducted with 18 strains of oleaginous yeasts in shaken flask on the OPE-based medium showed that Rhodosporidium toruloides NRRL 1091 and Cryptococcus laurentii UCD 68-201 gave the best results in terms of lipid production (5.8 and 4.5 g L, respectively) and accumulation (77 and 47% on a dry matter basis, respectively). The subsequent scale transfer of the process to a 3-L STR operated in batch mode halved the time required to reach the lipid peak with the ensuing increase in volumetric productivities in R. toruloides NRRL 1091 (3646 mg L day) and C. laurentii UCD 68-201 (2970.7 mg L day). The biodiesel yields from the lipids of the former and the latter strain were 36.9 and 31.9%, respectively. Based on multivariate analysis of fatty acid methyl ester compositions, the lipids from the former and the latter strain were highly resembling those of Jatropha and palm oils, two commonly used feedstocks for biodiesel manufacturing.
Topics: Basidiomycota; Biofuels; Citrus sinensis; Culture Media; Fruit; Fungi; Industrial Waste; Lipids; Plant Extracts; Rhodotorula
PubMed: 32236680
DOI: 10.1007/s00253-020-10579-y -
Ecotoxicology and Environmental Safety Jun 2020The ability of P. laurentii strain RY1 to remediate lead (Pb) from water was investigated in batch and column studies. The lead removal ability of non-viable biomass,...
The ability of P. laurentii strain RY1 to remediate lead (Pb) from water was investigated in batch and column studies. The lead removal ability of non-viable biomass, non-viable biomass immobilised on agar-agar (biobeads) and agar-agar at different pH was compared in batch studies. It was found that among the three, biobeads have maximum ability to remove Pb followed by biomass and agar-agar beads. Maximum and almost equal lead removal by biobeads was observed at both neutral and alkaline pH making it a novel and more applicable bioremediator as all other reported bioremediators have a single pH for optimum activity. Studies were performed to determine the optimum conditions for lead removal from aqueous solutions for biobeads. The physical and chemical characterization of the biobeads before and after Pb biosorption was done by using S.E.M. and F.T.I.R. respectively. The adsorption of Pb on biobeads obeyed the Langmuir adsorption isotherm and pseudo first order kinetics. These mean that the Pb binding sites are identical, located on the surface of the adsorbant and the rate of Pb removal from aqueous solution is directly proportional to the number of Pb binding sites on the biobeads. The thermodynamics of the biosorption process is also investigated. The binding capacity of the biobeads in batch study was found to be 52.91mg/gm which is higher in comparison to other reported yeast bioremediators. The used biobeads can be desorbed using 0.1(M) CaCl. The desorbed biobeads can be used subsequently for several cycles of lead removal making it cost-effective. Column studies were also performed for biobeads with the help of Thomas model for examining its suitability for industrial application. Maximum specific lead uptake of the biobeads when applied in the column was found to be 58.26mg/gm which being promising makes it suitable for application in industries involved in the treatment of wastewater contaminated with high amounts of lead. The high mass transfer co-efficient indicate that small sized column can be used effectively to remove high amounts of lead which makes the bioremediation process by the biobeads more economical and advantageous for industrial application. Several factors like effectiveness of the biobeads in Pbremoval at both neutral and alkaline pH, reusability, high mass transfer co-efficient, regenerability and high binding capacity makes it a novel versatile, cost-effective and high utility bioremediator.
Topics: Adsorption; Agar; Basidiomycota; Binding Sites; Biodegradation, Environmental; Biomass; Hydrogen-Ion Concentration; Kinetics; Lead; Models, Theoretical; Thermodynamics; Wastewater; Water Pollutants, Chemical; Water Purification
PubMed: 32182528
DOI: 10.1016/j.ecoenv.2020.110439 -
PloS One 2020Secondary peat swamp forest (PSF) arise by degradation of primary PSF as a result of fire and human activities. Yeasts diversity of Kuan Kreng (KK) and Rayong Botanical...
Secondary peat swamp forest (PSF) arise by degradation of primary PSF as a result of fire and human activities. Yeasts diversity of Kuan Kreng (KK) and Rayong Botanical Garden (RBG) PSF, which are two secondary PSF in southern and in eastern Thailand, respectively, were investigated. Yeasts were isolated from soil and peat soil by the dilution plate and enrichment techniques. From six samples collected from KK PSF, 35 strains were obtained, and they were identified based on the sequence analysis of the D1/D2 region of the large subunit (LSU) rRNA gene 13 species in 12 genera, and one potential new species of the genus Galactomyces were detected. Thirty-two strains were obtained from six samples collected from RBG PSF and 26 strains were identified as 13 known yeast species in 11 genera, whereas six strains were found to represent two potential new species of the genera Papiliotrema and Moesziomyces. Among yeast strains isolated from KK PSF, the number of strains in the phylum Ascomycota and Basidiomycota were equal, whereas there were slightly fewer strains in Ascomycota than in Basidiomycota among the strains obtained from RBG PSF. The yeast strains were evaluated for their antagonistic activities against fungal pathogens which cause rice diseases (Fusarium moniliforme, Helminthosporium oryzae, Rhizoctonia solani, Curvularia lunata and Pyricularia grisea) and postharvest disease of fruits (Phytophthora palmivora, Lasiodiplodia theobromae and Colletotrichum gloeosporioides). Twelve strains of seven species were found to be antagonistic yeast strains. Starmerella kuoi DMKU-SPS13-6, Hanseniaspora lindneri DMKU ESS10-9 and Piskurozyma taiwanensis DMKU-SPS12-2 capable to inhibit R. solani by 70.1-76.2%, Wickerhamomyces anomalus DMKU SPS6-1 and three Rhodotorula taiwanensis strains (DMKU SPS8-1, DMKU ESS9-3, DMKU SPS9-2) inhibited C. lunata by 69.8-71.9%, Hanseniaspora lindneri DMKU ESS10-9 and Scheffersomyces spartinae DMKU SPS9-3 inhibited P. grisea by 81.9-84.4% and four Papiliotrema laurentii strains (DMKU-SPS15-1, DMKU-ESS11-2, DMKU-ESS8-2, DMKU-ESS6-4) inhibited P. palmivora by 53.2-59.5%.
Topics: Forests; Fruit; Geography; Phylogeny; Plant Diseases; Soil; Soil Microbiology; Thailand; Wetlands; Yeasts
PubMed: 32176885
DOI: 10.1371/journal.pone.0230269 -
Journal of Infection in Developing... Jun 2019Fungi of the genus Cryptococcus are cosmopolitan and may be agents of opportunistic mycoses in immunocompromised and sometimes immunocompetent individuals. Cryptococcus...
INTRODUCTION
Fungi of the genus Cryptococcus are cosmopolitan and may be agents of opportunistic mycoses in immunocompromised and sometimes immunocompetent individuals. Cryptococcus species are frequently isolated from trees and bird excreta in the environment and infection occurs by inhalation of propagules dispersed in the air. The aim was to investigate Cryptococcus species in bird excreta and tree hollows located in a university hospital area and in an academic area of a university campus.
METHODOLOGY
A total of 40 samples of bird excreta and 41 samples of tree hollows were collected. The identification of the isolates was done by classical methodology and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.
RESULTS
Twenty (62.5%) isolates of Cryptococcus were found in bird excreta and 12 (37.5%) in tree hollows. C. laurentii (currently Papiliotrema laurentii) was the most frequent species in both samples, being found in 5 samples of excreta and in 8 tree hollows. The diversity of species found in excreta (C. laurentii, C. albidus [currently Naganishia albida], C. liquefaciens [currently N. liquefaciens], C. friedmanii [currently N. friedmannii] and others) was higher than in tree hollows (C. laurentii, C. flavescens [currently Papiliotrema flavescens], and other yeasts).
CONCLUSION
Many Cryptococcus species were isolated from excreta and tree hollows, and this fact is important for understanding the environmental epidemiology of those emerging pathogens for public health, as a way to implement surveillance actions and control of cryptococcosis.
Topics: Academic Medical Centers; Animals; Birds; Cryptococcus; Environmental Microbiology; Feces; Hospitals, University
PubMed: 32058990
DOI: 10.3855/jidc.10849