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Applied and Environmental Microbiology May 2024Given the multitude of extracellular enzymes at their disposal, many of which are designed to degrade nature's polymers (lignin, cutin, cellulose, etc.), fungi are adept...
Given the multitude of extracellular enzymes at their disposal, many of which are designed to degrade nature's polymers (lignin, cutin, cellulose, etc.), fungi are adept at targeting synthetic polyesters with similar chemical composition. Microbial-influenced deterioration of xenobiotic polymeric surfaces is an area of interest for material scientists as these are important for the conservation of the underlying structural materials. Here, we describe the isolation and characterization of the 5307AH () cutinase, Plcut1. is basidiomycete yeast with the ability to disperse Impranil-DLN (Impranil), a colloidal polyester polyurethane, in agar plates. To test whether the fungal factor involved in this clearing was a secreted enzyme, we screened the ability of culture supernatants to disperse Impranil. Using size exclusion chromatography (SEC), we isolated fractions that contained Impranil-clearing activity. These fractions harbored a single ~22 kD band, which was excised and subjected to peptide sequencing. Homology searches using the peptide sequences identified, revealed that the protein Papla1 543643 (Plcut1) displays similarities to serine esterase and cutinase family of proteins. Biochemical assays using recombinant Plcut1 confirmed that this enzyme has the capability to hydrolyze Impranil, soluble esterase substrates, and apple cutin. Finally, we confirmed the presence of the Plcut1 in culture supernatants using a custom antibody that specifically recognizes this protein. The work shown here supports a major role for the Plcut1 in the fungal degradation of natural polyesters and xenobiotic polymer surfaces.IMPORTANCEFungi play a vital role in the execution of a broad range of biological processes that drive ecosystem function through production of a diverse arsenal of enzymes. However, the universal reactivity of these enzymes is a current problem for the built environment and the undesired degradation of polymeric materials in protective coatings. Here, we report the identification and characterization of a hydrolase from 5307AH, an aircraft-derived fungal isolate found colonizing a biodeteriorated polymer-coated surface. We show that secretes a cutinase capable of hydrolyzing soluble esters as well as ester-based compounds forming solid surface coatings. These findings indicate that this fungus plays a significant role in biodeterioration through the production of a cutinase adept at degrading ester-based polymers, some of which form the backbone of protective surface coatings. The work shown here provides insights into the mechanisms employed by fungi to degrade xenobiotic polymers.
Topics: Carboxylic Ester Hydrolases; Fungal Proteins; Recombinant Proteins; Polyesters; Hydrolysis
PubMed: 38624219
DOI: 10.1128/aem.01694-23 -
Revista Da Sociedade Brasileira de... 2024Previously considered saprobe and non-pathogenic, the fungus Papiliotrema laurentii (formerly known as Cryptococcus laurentii), is rarely associated with human...
Previously considered saprobe and non-pathogenic, the fungus Papiliotrema laurentii (formerly known as Cryptococcus laurentii), is rarely associated with human infection. Nevertheless, there has been an increase in reported infections by non-neoformans cryptococci. After a literature search on the Cochrane Library, LILACS, SciELO, MEDLINE, PubMed, and PMC (PubMed Central) databases, we conclude that this is the first case report of fungemia and probable meningitis caused by Papiliotrema laurentii in a previously immunocompetent host with associated COVID-19.
Topics: Humans; Fungemia; Cryptococcosis; COVID-19; SARS-CoV-2; Cryptococcus; Basidiomycota
PubMed: 38324809
DOI: 10.1590/0037-8682-0480-2024 -
Journal of Applied Microbiology Nov 2023This study aimed to determine the efficacy of the soil yeasts Papiliotrema laurentii S-08 and Saitozyma podzolica S-77 for plant growth promotion (PGP) and biocontrol of...
AIM
This study aimed to determine the efficacy of the soil yeasts Papiliotrema laurentii S-08 and Saitozyma podzolica S-77 for plant growth promotion (PGP) and biocontrol of wilt disease in brinjal plants while applying yeasts individually or as a consortium in pot experiments.
METHODS AND RESULTS
The yeasts were tested for various PGP characteristics and antagonistic activity against the phytopathogen Fusarium oxysporum f. sp. melongenae. Both the yeast isolates demonstrated some PGP attributes as well as inhibited the growth of the phytopathogen. A gas chromatography-mass spectrometry analysis of the yeast metabolites revealed the presence of several antifungal compounds. The pot experiment performed under nursery conditions showed that applying these yeasts, individually or in consortium, decreased the percent disease incidence in brinjal seedlings while significantly enhancing their growth parameters.
CONCLUSION
Papiliotrema laurentii S-08 and S. podzolica S-77 can be used in brinjal plants as plant growth promoters and also as biocontrol agents against the brinjal wilt disease.
Topics: Solanum melongena; Fusarium; Soil; Saccharomyces cerevisiae; Plants; Plant Diseases
PubMed: 37930719
DOI: 10.1093/jambio/lxad252 -
JPMA. the Journal of the Pakistan... Oct 2023Infections caused by non-neoformans Cryptococcus spp., including Cryptococcus laurentii, previously thought to be saprophyte and non-pathogenic, have become more common...
Infections caused by non-neoformans Cryptococcus spp., including Cryptococcus laurentii, previously thought to be saprophyte and non-pathogenic, have become more common during the past few years, particularly in immunocompromised hosts. To the best of our knowledge here, we present the first case of meningitis in an immunocompromised patient due to a fungus that has never been reported in Pakistan. Our patient, a 40-year old male, who had acquired immunodeficiency syndrome (AIDS) was diagnosed as Cryptococcus laurentti meningitis, with a rare neurological manifestation i.e., cryptococcomas and lepto-meningitis. We presume that exposure to pigeon droppings and acquired immunodeficiency syndrome were the risk factors for this case report. He was treated with liposomal Amphotericin (LAMB) and fluconazole but unfortunately, he rapidly deteriorated and ultimately succumbed to the infection. This case underscores the significance of prompt diagnosis and vigorous treatment of Cryptococcus laurentii meningitis, as well as the need for continued surveillance in immunocompromised individuals.
Topics: Male; Humans; Adult; Acquired Immunodeficiency Syndrome; Cryptococcosis; Cryptococcus; Meningitis; Cryptococcus neoformans; Antifungal Agents
PubMed: 37876081
DOI: 10.47391/JPMA.8582 -
Scientific Reports Sep 2023The Cryptococcus genus comprises more than 100 species, of which C. neoformans and C. gattii are the leading cause of cryptococcosis. The distribution of C. gattii and...
The Cryptococcus genus comprises more than 100 species, of which C. neoformans and C. gattii are the leading cause of cryptococcosis. The distribution of C. gattii and C. neoformans species complexes has been extensively studied and widely reported globally. Other species such as Naganishia albida, Papiliotrema laurentii, and Papiliotrema flavescens have been reported as pathogenic yeasts. Since there are no reports of environmental isolation in the Boyacá region (Colombia), this study aimed to isolate and characterize Cryptococcus and Cryptococcus-like yeasts from pigeon feces, Eucalyptus, and olive trees distributed in the municipalities of Tunja and Ricaute Alto. The environmental data was recovered, and the isolations obtained were identified by microscopy, biochemical test, MALDI-TOF MS, URA5-RFLP, and sequencing of the ITS and LSU loci. For the 93 pigeon dropping samples collected in Tunja, 23 yielded to C. neoformans, 3 to N. globosa, 2 N. albida and 1 to P. laurentii. Of the 1188 samples collected from olive trees, 17 (1.43%) positive samples were identified as C. gattii species complex (4), C. neoformans species complex (2), P. laurentii (3), N. albida (2), N. globosa (5) and P. flavescens (1). Likewise, specimens of C. neoformans presented molecular type VNI and molecular type VNII; for C. gattii the molecular types found were VGIII and one VGIV by URA5-RFLP but VGIII by MALDI-TOF and sequencing of the ITS and LSU. Therefore, it can be concluded that the species of Cryptococcus, Naganishia and Papiliotrema genera, are present in the environment of Boyacá, and show a predilection for climate conditions that are typical of this region.
Topics: Animals; Colombia; Cryptococcus neoformans; Cryptococcus gattii; Cryptococcosis; Climate; Columbidae; Olea
PubMed: 37735454
DOI: 10.1038/s41598-023-41994-6 -
Antonie Van Leeuwenhoek Nov 2023Biodiesel is an interesting alternative to petroleum diesel as it is renewable, biodegradable, and has a low pollutant content. Yeast oils can be used for biodiesel...
Biodiesel is an interesting alternative to petroleum diesel as it is renewable, biodegradable, and has a low pollutant content. Yeast oils can be used for biodiesel production instead of edible oils, mitigating the use of arable land and water for biodiesel production. Maximum lipid accumulation is reached at 48 h of cultivation by the oleaginous yeast Papiliotrema laurentii UFV-1. Nevertheless, the effects of carbon and nitrogen concentrations on lipid accumulation, as well as the regulation of lipid metabolism in this yeast are still not well-characterised. Therefore, this work evaluated the effects of carbon and nitrogen concentrations on the lipid accumulation in P. laurentti, the expression of the ACC gene, and the activity of the enzyme acetyl-CoA carboxylase (ACCase) in different carbon:nitrogen ratios (C:N) and glucose concentrations. The variation of ammonium sulfate concentration did not affect the growth and lipid accumulation in P. laurentii UFV-1. On the other hand, glucose concentration remarkably influenced biomass and lipid production by this yeast. Therefore, the carbon concentration is more important than the nitrogen concentration for lipid production by P. laurentii UFV-1. Importantly, the levels of both ACC gene expression and ACCase activity were maximum during the late-exponential growth phase and decreased after reaching the highest lipid contents, which was easier evidenced during the accumulation and maximum lipid levels. As such, the reduction of ACCase enzyme activity seems to be related to the decrease in the expression level of the ACC gene.
PubMed: 37676572
DOI: 10.1007/s10482-023-01874-5 -
AIMS Microbiology 2023The diversity of duckweed () associated yeasts was studied using a culture-dependent method. A total of 252 yeast strains were isolated from 53 duckweed samples out of...
The diversity of duckweed () associated yeasts was studied using a culture-dependent method. A total of 252 yeast strains were isolated from 53 duckweed samples out of the 72 samples collected from 16 provinces in Thailand. Yeast identification was conducted based on the D1/D2 region of the large subunit (LSU) rRNA gene sequence analysis. It revealed that 55.2% and 44.8% yeast species were Ascomycota and Basidiomycota duckweed associated yeasts, respectively. Among all, , a basidiomycetous yeast, was found as the most prevalent species showing a relative of frequency and frequency of occurrence of 21.8% and 25%, respectively. In this study, high diversity index values were shown, indicated by the Shannon-Wiener index (), Shannon equitability index () and Simpson diversity index () values of 3.48, 0.86 and 0.96, respectively. The present results revealed that the yeast community on duckweed had increased species diversity, with evenness among species. Principal coordinate analysis (PCoA) revealed no marked differences in yeast communities among duckweed genera. The species accumulation curve showed that the observed species richness was lower than expected. Investigation of the plant growth promoting traits of the isolated yeast on duckweed revealed that 178 yeast strains produced indole-3-acetic acid (IAA) at levels ranging from 0.08-688.93 mg/L. Moreover, siderophore production and phosphate solubilization were also studied. One hundred and seventy-three yeast strains produced siderophores and exhibited siderophores that showed 0.94-2.55 activity units (AU). One hundred six yeast strains showed phosphate solubilization activity, expressed as solubilization efficiency (SE) units, in the range of 0.32-2.13 SE. This work indicates that duckweed associated yeast is a potential microbial resource that can be used for plant growth promotion.
PubMed: 37649804
DOI: 10.3934/microbiol.2023026 -
Biointerphases May 2023Microbial growth on surfaces poses health concerns and can accelerate the biodegradation of engineered materials and coatings. Cyclic peptides are promising agents to...
Microbial growth on surfaces poses health concerns and can accelerate the biodegradation of engineered materials and coatings. Cyclic peptides are promising agents to combat biofouling because they are more resistant to enzymatic degradation than their linear counterparts. They can also be designed to interact with extracellular targets and intracellular targets and/or self-assemble into transmembrane pores. Here, we determine the antimicrobial efficacy of two pore-forming cyclic peptides, α-K3W3 and β-K3W3, against bacterial and fungal liquid cultures and their capacity to inhibit biofilm formation on coated surfaces. These peptides display identical sequences, but the additional methylene group in the peptide backbone of β-amino acids results in a larger diameter and an enhancement in the dipole moment. In liquid cultures, β-K3W3 exhibited lower minimum inhibitory concentration values and greater microbicidal power in reducing the number of colony forming units (CFUs) when exposed to a gram-positive bacterium, Staphylococcus aureus, and two fungal strains, Naganishia albida and Papiliotrema laurentii. To evaluate the efficacy against the formation of fungal biofilms on painted surfaces, cyclic peptides were incorporated into polyester-based thermoplastic polyurethane. The formation of N. albida and P. laurentii microcolonies (105 per inoculation) for cells extracted from coatings containing either peptide could not be detected after a 7-day exposure. Moreover, very few CFUs (∼5) formed after 35 days of repeated depositions of freshly cultured P. laurentii every 7 days. In contrast, the number of CFUs for cells extracted from the coating without cyclic peptides was >8 log CFU.
Topics: Polyurethanes; Coated Materials, Biocompatible; Anti-Infective Agents; Biofilms; Peptides; Peptides, Cyclic; Anti-Bacterial Agents; Microbial Sensitivity Tests
PubMed: 37289032
DOI: 10.1116/6.0002515 -
Unusual Presentation of Non- Neoformans Cryptococcal Infection: Cutaneous Cryptococcosis Caused by .Skinmed 2023
Topics: Humans; Cryptococcosis; Cryptococcus; Basidiomycota
PubMed: 36987830
DOI: No ID Found -
Fungal Genetics and Biology : FG & B Jan 2023The production of yeast oil from lignocellulosic biomasses is impaired by inhibitors formed during the pretreatment step, mainly acetic acid. Herein, we applied Adaptive...
The production of yeast oil from lignocellulosic biomasses is impaired by inhibitors formed during the pretreatment step, mainly acetic acid. Herein, we applied Adaptive Laboratory Evolution (ALE) to select three Acetic acid Tolerant Strains (ATS) of P. laurentii UFV-1. Different phenotypes emerged alongside evolution. The ATS II presented trade-offs in the absence of acetic acid, suggesting that it displays a specialized phenotype of tolerance to growth on organic acids. On the other hand, ATS I and ATS III presented phenotypes associated with the behavior of generalists. ATS I was considered the most promising evolved strain as it displayed the oleaginous phenotype in all conditions tested. Thus, we applied whole-genome sequencing to detect the mutations that emerged in this strain during the ALE. We found alterations in genes encoding proteins involved in different cellular functions, including multidrug resistance (MDR) transporters, energy metabolism, detoxification, coenzyme recycling, and cell envelope remodeling. To evaluate acetic acid stress responses, both parental and ATS I strains were cultivated in chemostat mode in the absence and presence of acetic acid. In contrast to ATS I, the parental strain presented alterations in the cell envelope and cell size under acetic acid stress conditions. Furthermore, the parental strain and the ATS I presented differences regarding acetic acid assimilation. Contrary to the parental strain, the ATS I displayed an increase in unsaturated fatty acid content irrespective of acetic acid stress, which might be related to improved tolerance to acetic acid. Altogether, these results provided insights into the mechanisms involved with the acetic acid tolerance displayed by ATS I and the responses of P. laurentii to this stressful condition.
Topics: Acetic Acid; Saccharomyces cerevisiae; Phenotype; Membrane Transport Proteins
PubMed: 36528339
DOI: 10.1016/j.fgb.2022.103765