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A 6-year-old 21.5 kg castrated male Siberian Husky was presented for acute onset of lethargy, vomiting, hemorrhagic diarrhea, and inappetence. Physical examination revealed marked discomfort upon abdominal palpation and 5%–7% dehydration. The CBC and biochemical profile revealed changes consistent with mild to moderate inflammation, dehydration, and gastrointestinal (GI) disease. Despite aggressive gastrointestinal support, anorexia persisted, and an upper GI endoscopy was performed in conjunction with esophagostomy tube placement. Endoscopy revealed abnormal gastric mucosa characterized by moderately well-demarcated areas of blue-black discoloration. Impression smears of a gastric biopsy revealed abundant extracellular yeasts with morphology most consistent with Candida spp. and frequent extracellular cocci. Similar yeast and bacteria, in lower numbers, were observed on cytologic analysis of a direct smear of the rectal mucosa. A rectal swab submitted for fungal culture yielded pure growth of fungal yeasts identified as Diutina (formerly Candida) rugosa by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry. The dog's clinical signs improved with fluconazole, and he was discharged. Follow-up fungal culture of a rectal swab showed no growth of D. rugosa. To the authors' knowledge, this is the first case report that describes the clinical, hematologic, cytologic, and gross findings of enteric colonization by D. rugosa in a dog. [ABSTRACT FROM AUTHOR]

Aims: This study was aimed to characterise nine clinical isolates in our culture collection that were categorized as Diutina species based on their molecular genetic profiles. D. rugosa is a species complex comprising four taxa., i.e., D. rugosa sensu stricto, D. pseudorugosa, D. neorugosa and D. mesorugosa. The most commonly used phenotypic identification methods for yeasts often lead to the misidentification of this species complex. Methodology and results: The Diutina isolates were received from two local referral hospitals as pure cultures. Species confirmation was performed using conventional phenotypic methods; CHROMagar and RapID Yeast Plus Kit. To study the inter- and intraspecific relationships among the clinical isolates, ITS region, D1/D2 domain and random amplified polymorphic DNA (RAPD) analyses were performed. The results were further validated using the housekeeping gene sequence similarity technique coupled with pairwise sequence alignment. The results from phenotypic methods results were ambiguous and inconclusive. The sequence analyses of ITS regions and D1/D2 domains revealed that the samples consisted of three yeast species; D. rugosa complex: D. rugosa (n=1), D. mesorugosa (n=6), Candida pararugosa (n=1) and Meyerozyma guilliermondii (n=1). The RAPD analysis with random primers, OPG4, OPG11 and OPA18, demonstrated good banding patterns that could distinguish between the Diutina isolates. The pairwise sequence alignment revealed that the Diutina isolates were genetically similar to D. rugosa ATCC 10571. Conclusion, significance and impact of study: The molecular methods, D1/D2 domain, ITS1 and ITS4 region, and RAPD analyses have proven helpful for accurately identifying the yeasts, especially closely related species; D. rugosa and D. mesorugosa. [ABSTRACT FROM AUTHOR]

Infections caused by opportunistic yeast pathogens have increased over the last years. These infections can be originated by a large number of diverse yeast species of varying incidence, and with distinct clinically relevant phenotypic traits, such as different susceptibility profiles to antifungal drugs, which challenge diagnosis and treatment. Diutina rugosa (syn. Candida rugosa) and Trichomonascus ciferrii (syn. Candida ciferrii) are two opportunistic rare yeast pathogens, which low incidence (< 1%) limits available clinical experience. Furthermore, these yeasts have elevated Minimum Inhibitory Concentration (MIC) levels to at least one class of antifungal agents. This makes it more difficult to manage their infections, and thus they are associated with high rates of mortality and clinical failure. With the aim of improving our knowledge on these opportunistic pathogens, we assembled and annotated their genomes. A phylogenomics approach revealed that genes specifically duplicated in each of the two species are often involved in transmembrane transport activities. These genomes and the reconstructed complete catalog of gene phylogenies and homology relationships constitute useful resources for future studies on these pathogens.

The potential use of alternative culture media towards the development of a sustainable bioprocess to produce lipases by Diutina rugosa is clearly demonstrated. First, a synthetic medium containing glucose, peptone, yeast extract, oleic acid, and ammonium sulfate was proposed, with lipase activity of 143 U/L. Then, alternative culture media formulated with agro-industrial residues, such as molasses, corn steep liquor (CSL), and olive mill waste (OMW), were investigated. An experimental design was conducted, and only CSL concentration was found to have a positive effect in lipase production. The highest lipase activity (561 U/L) was produced on a mixture of molasses (5 g/L), CSL (6 g/L), OMW (0.5% v/v), 0.5 g/L of ammonium sulfate, and 3 g/L of peptone at 24 h of cultivation. Lipase production was also carried out in a 1-L bioreactor leading to a slightly higher lipase activity at 24 h of cultivation. The semi-purified enzyme exhibits an optimum temperature and pH of 40 °C and 7.0, respectively. Finally, the media cost per unit of lipase produced (UPC) was influenced by the medium components, specially by the inducer used. The lowest UPC was obtained when the agro-industrial residues were combined and used at the improved concentrations. [ABSTRACT FROM AUTHOR]

Infections caused by opportunistic yeast pathogens have increased over the last years. These infections can be originated by a large number of diverse yeast species of varying incidence, and with distinct clinically relevant phenotypic traits, such as different susceptibility profiles to antifungal drugs, which challenge diagnosis and treatment. Diutina rugosa (syn. Candida rugosa) and Trichomonascus ciferrii (syn. Candida ciferrii) are two opportunistic rare yeast pathogens, which low incidence (, 1%) limits available clinical experience. Furthermore, these yeasts have elevated Minimum Inhibitory Concentration (MIC) levels to at least one class of antifungal agents. This makes it more difficult to manage their infections, and thus they are associated with high rates of mortality and clinical failure. With the aim of improving our knowledge on these opportunistic pathogens, we assembled and annotated their genomes. A phylogenomics approach revealed that genes specifically duplicated in each of the two species are often involved in transmembrane transport activities. These genomes and the reconstructed complete catalog of gene phylogenies and homology relationships constitute useful resources for future studies on these pathogens. [ABSTRACT FROM AUTHOR]

In this study, a new strain of D. rugosa isolated from chicken feces was identified and characterized. Phylogenetic analyses using the 5.8 internal transcribed spacer and 18S rDNA sequencing showed that this strain belongs to the species D. rugosa , and was thus named D. rugosa SD-17. Its general biological features were studied and compared with its closest related strain, D. rugosa ATCC 10571. The results showed that D. rugosa SD-17 formed a depression in the middle of the colony; furthermore, the cell wall was significantly thicker (P = 0.004) and the production of β-glucan was significantly higher (P < 0.001) compared to D. rugosa ATCC 10571. Intestinal environmental tolerance tests showed that D. rugosa SD-17 could thrive at the host intestinal temperature; approximately 45% of D. rugosa SD-17 survived at pH = 2 for 4 h and 0.3% of bile salts had no effect on growth. Colonization and adhesion tests showed that elimination of D. rugosa SD-17 was achieved after 20 h of oral administration, and the adhesion rate to Caco-2 cells reached 61.5% (P < 0.001). The results of this study indicate that D. rugosa SD-17 could be considered an appropriate probiotic candidate and may have potential use as a novel probiotic in animals. • D. rugosa had strain specific, and D. rugosa from different sources had different characteristics. • Production of glucan from D. rugosa SD-17 was significantly improved compared with the type strain. • D. rugosa SD-17 had strong resistance to simulated intestinal environment. • D. rugosa SD-17 had transient colonization of intestinal tract and high adhesion to Caco-2 cells. [ABSTRACT FROM AUTHOR]

Candida rugosa (recently reclassified Diutina rugosa) is an emerging pathogen affecting humans and animals. Candida resistance to existing drugs is an important factor to be monitored, as well as the need of researching alternatives to conventional antifungals. Here, we evaluated the in vitro effects of some antifungals and major components of essential oils by the broth microdilution method (CLSI M27-A3) against fifteen C. rugosa strains from animals isolated and molecular identificated. The results showed MIC 90 of: 0.125 μg/mL to ketoconazole and voriconazole, 0.25 μg/mL to micafungin, 0.5 μg/mL to anidulafungin, 1 μg/mL to caspofungin, 2 μg/mL to amphotericin B, itraconazole and flucytosin, 8 μg/mL to fluconazole, 16 μg/mL to nystatin and >128 μg/mL to terbinafine. The compounds carvacrol (MIC 90 320 μg/mL), thimol (MIC 90 320 μg/mL) and cinnamaldehyde (MIC 90 160 μg/mL) demonstrated antifungal activity against the samples tested. [ABSTRACT FROM AUTHOR]

Isolation, identification, and characterization of newly isolated yeast, Diutina rugosa capable of decolorizing indigo dye were investigated in this study. Molecular and phylogenetic analyses of 23S rRNA sequence data indicated that the yeast belonged to the new genus, Diutina . The optimization of physicochemical parameters such as pH of the solution (2–8), initial dye concentration (10–60 mg L −1 ), adsorbent mass (0.1–2 g), and temperature (10–50 °C) was studied to scale- up the conditions of dye removal. Furthermore, complete decolorization (99.97%) of indigo dye (10 mg L −1 ) was achieved at pH 2, temperature 30 °C and 2.0 g cell biomass within 5 days. Degradation was monitored through UV–vis spectrophotometric, FTIR, and GCMS analyses. The results of FTIR analysis obtained revealed the loss and shifts in spectra peaks of the experimental in comparison with the biological control. Possible degradation pathway was proposed using the intermediate metabolites; 1, 2-dihydro-3 H -indol-3-one and cyclopentanone obtained through GCMS analysis. The enzyme analyses revealed significant inductions and major roles played by NADH-DCIP reductase and lignin peroxidase in the asymmetric cleavage, initial reduction and deamination of indigo dye. The equilibrium experimental data were fitted to Langmuir, Freundlich and Temkin adsorption isotherms with high adjusted coefficient of determination values; adjR 2 = 0.907, adjR 2 = 0.867, and adjR 2 = 0.965 respectively. However, the Langmuir and Temkin adsorption isotherms affirmed the monolayer and heterogeneous biosorption characteristics of Diutina rugosa. Temkin adsorption isotherm model (R 2 = 0.971) represented the best fit of experimental data than other isotherm models. [ABSTRACT FROM AUTHOR]

Echinocandins are recommended as a first-line therapy for invasive candidiasis. Candida rugosa was recently transferred to the new genus Diutina . We have determined the in vitro killing kinetics of two echinocandins, anidulafungin, and caspofungin and their in vivo efficacy, administering doses of 5 or 10 mg/kg, and 1 or 5 mg/kg, respectively against 2 clinical strains of D. rugosa . Both drugs showed a fungicidal concentration-dependent activity and, in a neutropenic murine model of disseminated infection, were able to reduce tissue burden and to prolong survival of mice. These results suggest that both echinocandins could be useful to treat infections by this fungus when isolates show minimal inhibitory concentrations within the range of susceptibility for both drugs. [ABSTRACT FROM AUTHOR]

Candida rugosa (recently reclassified Diutina rugosa) is an emerging pathogen affecting humans and animals. Candida resistance to existing drugs is an important factor to be monitored, as well as the need of researching alternatives to conventional antifungals. Here, we evaluated the in vitro effects of some antifungals and major components of essential oils by the broth microdilution method (CLSI M27-A3) against fifteen C. rugosa strains from animals isolated and molecular identificated. The results showed MIC 90 of: 0.125μg/mL to ketoconazole and voriconazole, 0.25μg/mL to micafungin, 0.5μg/mL to anidulafungin, 1μg/mL to caspofungin, 2μg/mL to amphotericin B, itraconazole and flucytosin, 8μg/mL to fluconazole, 16μg/mL to nystatin and >128μg/mL to terbinafine. The compounds carvacrol (MIC 90 320μg/mL), thimol (MIC 90 320μg/mL) and cinnamaldehyde (MIC 90 160μg/mL) demonstrated antifungal activity against the samples tested., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)