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The current trend is the promotion of antioxidants that are beneficial for both health and the environment. Candida utilis have garnered considerable attention due to their commendable attributes such as non-toxicity and the ability to thrive in waste. Therefore, Candida utilis was used as raw material to isolate and identify new antioxidant peptides by employing methods such as ultrafiltration, DEAE Sepharose Fast Flow, and liquid chromatography-tandem mass spectrometry. The antioxidant mechanism of peptides was investigated by molecular docking. The properties of antioxidant peptides were evaluated using a variety of computational tools. This study resulted in the identification of two novel antioxidant peptides. According to the molecular docking results, the antioxidant mechanism of Candida utilis peptides operates by obstructing the entry to the myeloperoxidase activity cavity. The (-) CDOCKER energy of antioxidant peptides was 6.2 and 6.1 kcal/mol, respectively. Additionally, computer predictions indicated that antioxidant peptides exhibited non-toxicity and poor solubility., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objectives: Head and neck cancer (HNC) impairs patient immunity and increases susceptibility to oral fungal infections (OFIs). Effectively treating such infections requires accurate identification of the causative pathogens. This study aimed to characterize the mycobiota profile of OFIs in HNC patients undergoing radiation treatment (RT)., Materials and Methods: A 6-year retrospective analysis of oral mucosal samples from HNC patients with a history of RT and OFIs between 2014 and 2019 was conducted using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) profiling. Samples from the Clinical Microbiology Laboratory at Karolinska University Hospital were evaluated for mycobiota diversity and species co-occurrence patterns in the ongoing-RT and post-RT groups., Results: A total of 190 oral fungi (88% Candida, 5% Pichia) were isolated from 162 HNC patients receiving RT. In the ongoing-RT group, the emergent non-albicans Candida (NAC) species; F. solani and C. jadinii, were detected for the first time. The dominant pathogens in both ongoing and post-RT groups were C. albicans, C. glabrata, P. kudriavzevii, C. parapsilosis, and C. tropicalis, as shown by Venn analysis. Network analysis revealed greater fungi diversity and multi-species co-occurrence in the ongoing-RT group. C. albicans commonly co-occurred with C. glabrata in both ongoing-RT (21%) and post-RT groups (30%)., Conclusion: MALDI-TOF MS identified a wide range of oral fungal species in HNC patients receiving RT. While C. albicans remains the most prevalent OFIs pathogen, multi-species co-occurrence and novel NACs were noted. Understanding the ecological interactions among these causative pathogens could significantly advance the development of effective therapeutics for treating OFIs in HNC patients., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The catalytic activity of Candida antarctica lipase B (CALB) immobilized on modified cellulose nanocrystals (CNC) with different hydrophobicity was investigated using experimental and theoretical approaches. Firstly, the modified CNC were characterized by multi-spectroscopic methods, water contact angle, scanning electron microscopy and thermogravimetric analysis. Moderately hydrophobic CNC were found to be an optimal support for CALB immobilization. Secondly, model systems contained a CALB molecule and different numbers of modified CNC molecules (CALB@3CNC-C16, CALB@10CNC-C16 and CALB@15CNC-C16) were prepared for molecular dynamics (MD) simulation. Root-mean-square fluctuation values (0.61-2.61 Å) of lid region were relatively high in CALB@10CNC-C16, indicating that modified CNC with moderate hydrophobicity favored forming a lid-open conformation of CALB. Finally, the esterification of oleic acid catalyzed by the immobilized CALB showed higher conversion (54.68 %) than free CALB (12.98 %). Insights into modified CNC with tunable properties provided by this study may be a potential support for improving the catalytic performance of lipases., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Oral candidiasis, a common opportunistic infection of the oral cavity, is mainly caused by the following four Candida species (in decreasing incidence rate): Candida albicans , Candida glabrata , Candida tropicalis , and Candida krusei . This study offers in-depth Raman spectroscopy analyses of these species and proposes procedures for an accurate and rapid identification of oral yeast species. We first obtained average spectra for different Candida species and systematically analyzed them in order to decode structural differences among species at the molecular scale. Then, we searched for a statistical validation through a chemometric method based on principal component analysis (PCA). This method was found only partially capable to mechanistically distinguish among Candida species. We thus proposed a new Raman barcoding approach based on an algorithm that converts spectrally deconvoluted Raman sub-bands into barcodes. Barcode-assisted Raman analyses could enable on-site identification in nearly real-time, thus implementing preventive oral control, enabling prompt selection of the most effective drug, and increasing the probability to interrupt disease transmission.

The objective of the current study was to examine the effects of yeasts on intestinal health and transcriptomic profiles from the distal intestine and spleen tissue of Atlantic salmon fed SBM-based diets in seawater. Cyberlindnera jadinii (CJ) and Wickerhamomyces anomalus (WA) yeasts were heat-inactivated with spray-drying (ICJ and IWA) or autolyzed at 50 °C for 16 h (ACJ and AWA), followed by spray-drying. Six diets were formulated, one based on fishmeal (FM), a challenging diet with 30% soybean meal (SBM) and four other diets containing 30% SBM and 10% of each of the four yeast fractions (i.e., ICJ, ACJ, IWA and AWA). The inclusion of CJ yeasts reduced the loss of enterocyte supranuclear vacuolization and reduced the population of CD8α labeled cells present in the lamina propria of fish fed the SBM diet. The CJ yeasts controlled the inflammatory responses of fish fed SBM through up-regulation of pathways related to wound healing and taurine metabolism. The WA yeasts dampened the inflammatory profile of fish fed SBM through down-regulation of pathways related to toll-like receptor signaling, C-lectin receptor, cytokine receptor and signal transduction. This study suggests that the yeast species, Cyberlindnera jadinii and Wickerhamomyces anomalus are novel high-quality protein sources with health-beneficial effects in terms of reducing inflammation associated with feeding plant-based diets to Atlantic salmon.

To overcome the limitations of the Limulus amebocyte lysate (LAL) assay method for the diagnosis of invasive fungal infection, we applied a reaction system combining recombinant β-glucan binding proteins and a scanning single-molecule counting (SSMC) method. A novel (1→3)-β-D-glucan recognition protein (S-BGRP) and a (1→6)-β-glucanase mutant protein were prepared and tested for the binding of (1→6)-branched (1→3)-β-D-glucan from fungi. S-BGRP and (1→6)-β-glucanase mutant proteins reacted with β-glucan from Candida and Aspergillus spp. Although LAL cross-reacted with plant-derived β-glucans, the new detection system using the SSMC method showed low sensitivity to plant (1→3)-β-D-glucan, which significantly improved the appearance of false positives, a recognized problem with the LAL method. Measurement of β-glucan levels by the SSMC method using recombinant β-glucan-binding proteins may be useful for the diagnosis of fungal infections. This study shows that this detection system could be a new alternative diagnostic method to the LAL method.

Using hydrolysates of the North American prairie grass prairie cordgrass buffered at pH 4.5, 5.0, 5.5 or 6.0, xylitol production, xylitol yield, cell biomass production and productivity were investigated for three strains of yeast Candida. Of the three strains, the highest xylitol concentration of 20.19 g xylitol (g xylose consumed)-1 and yield of 0.89 g xylitol (g xylose consumed)-1 were produced by Candida mogi ATCC 18364 when grown for 120 h at 30° C on the pH 5.5-buffered hydrolysate-containing medium. The highest biomass level being 7.7 g cells (kg biomass)-1 was observed to be synthesized by Candida guilliermondii ATCC 201935 after 120 h of growth at 30° C on a pH 5.5-buffered hydrolysate-containing medium. The highest xylitol specific productivity of 0.73 g xylitol (g cells h)-1 was determined for C. guilliermondii ATCC 20216 after 120 h of growth at 30°C on a pH 5.0-buffered hydrolysate-containing medium. Xylitol production and yield by the three Candida strains was higher on prairie cordgrass than what was previously observed for the same strains after 120 h at 30° C when another North American prairie grass big bluestem served as the plant biomass hydrolysate indicating that prairie cordgrass may be a superior plant biomass substrate.

To exploit the hydrolytic activity and high selectivity of immobilized lipase B from Candida antarctica on octyl agarose (CALB-OC) in the hydrolysis of triacetin and also to produce new value-added compounds from glycerol, this work describes a chemoenzymatic methodology for the synthesis of the new dimeric glycerol ester 3-((2,3-diacetoxypropanoyl)oxy)propane-1,2-diyl diacetate. According to this approach, triacetin was regioselectively hydrolyzed to 1,2-diacetin with CALB-OC. The diglyceride product was subsequently oxidized with pyridinium chlorochromate (PCC) and a dimeric ester was isolated as the only product. It was found that the medium acidity during the PCC treatment and a high 1,2-diacetin concentration favored the formation of the ester. The synthesized compounds were characterized using IR, MS, HR-MS, and NMR techniques. The obtained dimeric ester was evaluated at 100 ppm against seven bacterial strains and two Candida species to identify its antimicrobial activity. The compound has no inhibitory activity against the bacterial strains used but decreased C. albicans and C. parapsilosis growth by 49% and 68%, respectively. Hemolytic activity was evaluated, and the results obtained support the use of the dimeric ester to control C. albicans and C. parapsilosis growth in non-intravenous applications because the compound shows hemolytic activity.

The present study is an attempt to determine the lipid composition of Candida auris and to highlight if the changes in lipids can be correlated to high drug resistance encountered in C. auris. For this, the comparative lipidomics landscape between drug-susceptible (CBS10913T) and a resistant hospital isolate (NCCPF_470033) of C. auris was determined by employing high throughput mass spectrometry. All major groups of phosphoglycerides (PGL), sphingolipids, sterols, diacylglycerols (DAG) and triacylglycerols (TAG), were quantitated along with their molecular lipid species. Our analyses highlighted several key changes where the NCCPF_470033 showed an increase in PGL content, specifically phosphatidylcholine, phosphatidylglycerol, phosphatidylserine, phosphatidylinositol, and phosphatidylethanolamine; odd chain containing lipids and accumulation of 16:1-DAG and 16:0-DAG; depletion of 18:1-TAG and 18:0-TAG. The landscape of molecular species displayed a distinct imprint between isolates. For example, the levels of unsaturated PGLs, contributed by both odd and even-chain fatty acyls were higher in resistant NCCPF_470033 isolate, resulting in a higher unsaturation index. Notwithstanding, several commonalities of lipid compositional changes between resistant C. auris and other Candida spp., the study could also identify distinguishable changes in specific lipid species in C. auris. Together, the data highlights the modulation of membrane lipid homeostasis associated with drug-resistant phenotype of C. auris., (© FEMS 2020.)

The present study examined the effect of six disruption methods of the cell wall (acid hydrolysis, ultrasonication, osmotic shock, pasteurization, homogenization with zirconia balls, and freezing/defrosting) on the efficiency of lipid extraction from yeast cells and the composition of fatty acids. Acid hydrolysis and sonication led to a significant increase in lipid extraction from Cyberlindnera jadinii ATCC 9950 and Rhodotorula glutinis LOCKR13 yeast cells. The amount of lipids extracted in these conditions increased for C. jadinii from 12.46 (biomass not subjected to any pretreatment) to 20.37 and 19.53 g/100 g d.w. after the application of acid hydrolysis and sonication, respectively, and for R. glutinis strain from 13.95 to 21.20 and 17.22 g/100 g d.w. , respectively, for the same methods. Initial sonication of biomass led to a significant reduction in the percentage of unsaturated fatty acids. The largest differences in fatty acid composition were found for the sample homogenized with zirconium balls. This process resulted in the degradation of both oleic acid and linolenic acid. The obtained results revealed that the method that significantly increases lipid extraction and does not change the composition of fatty acids is acid hydrolysis with hydrochloric acid. In addition, it is easy, cheap, does not require specialized equipment, and therefore can be implemented in any laboratory., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflicts of interest in this study., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Oxidative stress may result in different modes of cell death, such as necrosis, apoptosis and necroptosis. Currently, researchers are still striving to develop efficient tools/methods to distinguish the cell death modes in direct and label-free ways. In this study, we attempted to employ Raman micro-spectroscopy to observe the molecular changes in Candida utilis cells under oxidative stress induced by low-temperature plasma (LTP) and explore the spectroscopic biomarkers for the modes of cell death under oxidative stress. In this research, we confirmed that LTP could impose oxidative stress on the yeast cells, and recorded the changes of Raman signals of cytochrome c in the cells under LTP oxidative stress. Subsequently, we identified the biochemical and morphological characteristic features corresponding to different modes of cell death. Interestingly, we found that LTP under certain conditions could induce oxidative stress which caused the yeast cell death mainly by means of necroptosis, which was verified by Annexin V/PI, HMGB1 location assay and immunoprecipitation assay of the RIP1/RIP3 necrosome. Correspondingly, we also showed that the LTP induced necroptosis, associated with the increase of cytoplasmic Ca 2+ and mitochondrial ROS, the decrease of mitochondrial membrane potential, the release of oxidized cytochrome c from the mitochondrion to the cytoplasm, and the destruction of mitochondria in yeast cells. This work has therefore demonstrated that monitoring the redox state of cytochrome c using Raman micro-spectroscopy is very useful for distinguishing the modes of cell death and particularly may unveil the unique necroptosis process of cells under extrinsic oxidative stress.

Europe is heavily dependent on imported feed protein sources such as soybean meal (SBM); thus, investigating local sustainable alternatives is crucial to increase self-sufficiency. This study evaluated the effects of the inactivated yeast Cyberlindnera jadinii grown on local lignocellulosic sugars on the growth performance and digestive function of Ross 308 broiler chickens. A total of 1,000 male chicks were allocated to 20 pens. There were 5 replicate pens with 50 birds each, from 1 to 30 D after hatch. The birds were offered one conventional wheat-oat-SBM-based control diet and 3 diets with increasing levels of C. jadinii replacing 10, 20, and 30% of dietary crude protein (CP), whereas SBM levels were gradually decreased. The feed intake and weight gain of the birds decreased linearly, and feed conversion ratio increased linearly (P < 0.01) with increasing dietary levels of C. jadinii. Nevertheless, growth performance and feed intake were similar between the birds fed with control diets and diets containing 10% CP from C. jadinii in the starter and grower periods. The apparent ileal digestibility (AID) of dry matter, crude fat, organic matter, and carbohydrates was higher in control diets than in diets with 30% C. jadinii CP (P < 0.05) and decreased (P < 0.01) with incremental levels of dietary C. jadinii. Regardless, the AID of CP, starch, ash, and phosphorus was unaffected. Ileal villus height on day 10 was maintained in birds fed with diets containing 30% C. jadinii CP compared with the birds fed with control diets but was lower for birds fed with diets containing 10 and 20% C. jadinii protein (P < 0.05). To conclude, up to 10% C. jadinii CP can replace SBM CP in broiler chicken diets, maintaining growth performance and digestive function, whereas higher levels of C. jadinii may decrease bird performance. Altogether, this suggests the potential of C. jadinii as a local-based protein source in broiler chicken diets, contributing to a more sustainable feed., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

International concern over the recent emergence of Candida auris infections reflects not only its comparative ease of transmission and substantial mortality but the increasing level of resistance observed to all three major classes of antifungal drugs. Diminution in virulence has been reported for a wide range of fungal pathogens when the FK506-binding protein FKBP12 binds to that immunosuppressant drug and the binary complex then inhibits the fungal calcineurin signaling pathway. Structure-based drug design efforts have described modifications of FK506 which modestly reduce virulence for a number of fungal pathogens while also lessening the side effect of suppressing the tissue immunity response in the patient. To aid in such studies, we report the crystal structure of Candida auris FKBP12. As physiological relevance has been proposed for transient homodimerization interactions of distantly related fungal FKBP12 proteins, we report the solution NMR characterization of the homodimerization interactions of the FKBP12 proteins from both Candida auris and Candida glabrata., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Wadsworth Center, New York State Department of Health. Published by Elsevier Inc. All rights reserved.)

Opportunistic pathogens such as Candida species can use carboxylic acids, like acetate and lactate, to survive and successfully thrive in different environmental niches. These nonfermentable substrates are frequently the major carbon sources present in certain human body sites, and their efficient uptake by regulated plasma membrane transporters plays a critical role in such nutrient-limited conditions. Here, we cover the physiology and regulation of these proteins and their potential role in Candida virulence. This review also presents an evolutionary analysis of orthologues of the Saccharomyces cerevisiae Jen1 lactate and Ady2 acetate transporters, including a phylogenetic analysis of 101 putative carboxylate transporters in twelve medically relevant Candida species. These proteins are assigned to distinct clades according to their amino acid sequence homology and represent the major carboxylic acid uptake systems in yeast. While Jen transporters belong to the sialate:H + symporter (SHS) family, the Ady2 homologue members are assigned to the acetate uptake transporter (AceTr) family. Here, we reclassify the later members as ATO (acetate transporter ortholog). The new nomenclature will facilitate the study of these transporters, as well as the analysis of their relevance for Candida pathogenesis., (Copyright © 2020 Alves et al.)

Several studies have investigated the capacity of ATR-FTIR spectroscopy for fungal species discrimination. However, preparation methods vary among studies. This study aims to ascertain the effect of sample preparation on the discriminatory capacity of ATR-FTIR spectroscopy. Candida species were streaked to obtain colonies and spectra were collected from each preparation type, which included: (a) untreated colonies being directly transferred to the ATR crystal, (b) following washing and (c) following 24-h fixation in formalin. Spectra were pre-processed and principal component analysis (PCA) and K-means cluster analysis (KMC) were performed. Results showed that there was a clear discrimination between preparation types. Groups of spectra from untreated and washed isolates clustered separately due to intense protein, DNA and polysaccharide bands, whilst fixed spectra clustered separately due to intense polysaccharide bands. This signified that sample preparation had influenced the chemical composition of samples. Nevertheless, across preparation types, significant species discrimination was observed, and the polysaccharide (1200-900 cm -1 ) region was a common critical marker for species discrimination. However, different discriminatory marker bands were observed across preparation methods. Thus, sample preparation appears to influence the chemical composition of Candida samples; however, does not seem to significantly impact the species discrimination potential for ATR-FTIR spectroscopy.

The introduction of non-culture-based diagnostic techniques is revolutionizing the world of microbiological diagnosis and infection assessment. Fungi are no exception, and the introduction of biomarkers has opened up enormous expectations for better management of these entities. Biomarkers are diverse, their targets are also diverse and their evaluation has been done preferably in an individualized use and with deficient designs. Less is known about the value of the combined use of biomarkers and the impact of the negativity of two or more biomarkers on antifungal treatment decisions has been poorly studied. Given the paucity of prospective, randomized and definitive studies, we have convened experts from different fields, with an interest in invasive fungal infections, to answer some questions about the current relevant use of fungal biomarkers. This document summarizes the answers of these experts to the different questions., (©The Author 2020. Published by Sociedad Española de Quimioterapia. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)(https://creativecommons.org/licenses/by-nc/4.0/).)

Glycoconjugates found on cell walls of Candida species are fundamental for their pathogenicity. Laborious techniques have been employed to investigate the sugar composition of these microorganisms. Herein, we prepared a nanotool, based on the fluorescence of quantum dots (QDs) combined with the specificity of Cramoll lectin, to evaluate glucose/mannose profiles on three Candida species. The QDs-Cramoll conjugates presented specificity and bright fluorescence emission. The lectin preserved its biological activity after the conjugation process mediated by adsorption interactions. The labeling of Candida species was analyzed by fluorescence microscopy and quantified by flow cytometry. Morphological analyses of yeasts labeled with QDs-Cramoll conjugates indicated that C. glabrata (2.7 μm) was smaller when compared to C. albicans (4.0 μm) and C. parapsilosis sensu stricto (3.8 μm). Also, C. parapsilosis population was heterogeneous, presenting rod-shaped blastoconidia. More than 90% of cells of the three species were labeled by conjugates. Inhibition and saturation assays indicated that C. parapsilosis had a higher content of exposed glucose/mannose than the other two species. Therefore, QDs-Cramoll conjugates demonstrated to be effective fluorescent nanoprobes for evaluation of glucose/mannose constitution on the cell walls of fungal species frequently involved in candidiasis., (Copyright © 2019 Elsevier GmbH. All rights reserved.)

Candida species are becoming one of the pathogens developing antifungal resistance due to inappropriate treatment and overuse of antimycotic drugs in building construction and agriculture. Further, fungal infections are often difficult to detect, also due to slow in vitro growth of the organisms from clinical specimens. Thus, fast detection and discrimination of yeast cells in direct patient materials is essential for an adequate treatment and success rate. In this work, we investigated Candida species isolated from patients, by using surface-enhanced Raman scattering (SERS) combined with computational spectroscopy tools, aiming to detect and discriminate between the three considered species, Candida albicans, Candida glabrata, and Candida parapsilosis. Density functional theory (DFT) was used to calculate Raman spectra of yeasts' main cell wall components for elucidating the origin of the observed bands. Accurate assignments of normal modes helped for a better understanding of the interaction between silver nanoparticles with yeasts' cell wall. Further, SERS spectra were used as samples in a database on which we performed multivariate analyses. By Principal component analysis (PCA), we obtained a maximum variation of 79% between the three samples. Linear discriminant analysis (LDA) was successfully used to discriminate between the three species., (Copyright © 2019. Published by Elsevier B.V.)

An increasing effort is currently devoted to developing Raman spectroscopy for identification of microorganisms. Micro-Raman setups are typically used for this purpose with the limit that the intra-species and inter-species spectral variability are comparable, thus limiting the identification capability. To overcome this limit a meso-Raman approach is here implemented. Thin films of planktonic cells are analyzed throughout the collection of back-scattered light providing a Raman signal already averaged over tens of cells. The collecting of unpolarized (VU) and depolarized (HV) Raman signals increased the spectral information obtainable from the data, demonstrating the ability of the principal component analysis to differentiate the most common Candida species, namely C. glabrata, C. albicans, C. parapsilosis and C. tropicalis. The proposed method can contribute to bring Raman spectroscopy closer to its potential clinical use for fast identification of yeast cells., (Copyright © 2019 Elsevier B.V. All rights reserved.)

One of the main challenges in the food industry is to design strategies for the successful incorporation of natural sources of bioactive compounds. Recently, yogurts and other fermented dairy beverages have been proposed as ideal carriers of such bioactive compounds such as fatty acids and antioxidants that could improve consumers' health. However, the incorporation of new ingredients causes functional and structural modifications that may affect the consumers' preferences. In this work, a dairy beverage model supplemented with oleic acid has been designed by partial substitution of milk by Candida utilis single-cell protein extract. The changes in the structural properties of this new beverage were evaluated by following the fermentation process, pH, aggregate size, microstructure, and changes in rheological properties. Furthermore, molecular dynamics simulations were carried out to analyze the interaction between its main components. Our data revealed that samples with a percentage of milk substitution of 30% showed a higher viscosity as compared with the other percentages and less viscosity than the control (no substitution). These samples were then selected for fortification by incorporating oleic acid microcapsules. A concentration of 1.5 g/100 g was shown to be the optimal quantity of microcapsules for oleic acid supplementation. Molecular dynamic simulations revealed glutathione as an important component of the micro-gel structure. The present study forms the basis for novel studies where Candida utilis single-cell protein and microencapsulated essential oils could be used to design innovative bioproducts., (Copyright © 2019 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

The design of interfaces that selectively react with molecules to transform them into compounds of industrial interest is an emerging area of research. An example of such reactions is the hydrolytic conversion of ester-based molecules to lipids and alcohols, which is of interest to the food, and pharmaceutical industries. In this study, a functional bio-interfaced layer was designed to hydrolyze 4-nitrophenyl acetate (pNPA) and Ricinus Communis (castor) oil rich in triglycerides using lipase b from Candida antarctica (CALB, EC 3.1.1.3). The attachment of CALB was performed via non-covalent immobilization over a polymer film of vertically aligned cylinders that resulted from the self-assembly of the di-block copolymer polystyrene-block-poly(4-vinyl pyridine) (PS-b-P4VP). This polymer-lipase model will serve as the groundwork for the design of further bioactive layers for separation applications requiring similar hydrolytic processes. Results from the fabricated functional bio-interfaced material include cylinders with featured pore size of 19 nm, d spacing of 34 nm, and ca. 40 nm of thickness. The polymer-enzyme layers were physically characterized using AFM, XPS, and FTIR. The immobilized enzyme was able to retain 91% of the initial enzymatic activity when using 4-nitrophenyl acetate (pNPA) and 78% when exposed to triglycerides from castor oil., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Raman optical spectroscopy promises label-free bacterial detection, identification, and antibiotic susceptibility testing in a single step. However, achieving clinically relevant speeds and accuracies remains challenging due to weak Raman signal from bacterial cells and numerous bacterial species and phenotypes. Here we generate an extensive dataset of bacterial Raman spectra and apply deep learning approaches to accurately identify 30 common bacterial pathogens. Even on low signal-to-noise spectra, we achieve average isolate-level accuracies exceeding 82% and antibiotic treatment identification accuracies of 97.0±0.3%. We also show that this approach distinguishes between methicillin-resistant and -susceptible isolates of Staphylococcus aureus (MRSA and MSSA) with 89±0.1% accuracy. We validate our results on clinical isolates from 50 patients. Using just 10 bacterial spectra from each patient isolate, we achieve treatment identification accuracies of 99.7%. Our approach has potential for culture-free pathogen identification and antibiotic susceptibility testing, and could be readily extended for diagnostics on blood, urine, and sputum.

Rapid identification of Candida species is important for appropriate antifungal therapy of fungemia. The matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) system is a useful tool to identify bacteria and yeasts. In this study, we evaluated the feasibility of identifying yeasts after a short-term incubation on a solid medium. We tested 24 strains of eight Candida species. Blood culture bottles were spiked with a calibrated suspension of each Candida strain. Three different culture media, two types of blood culture bottles and three different incubation time points were tested. A multivariable random-effects logistic regression analysis was performed for determining factors independently associated with a successful MALDI-TOF MS identification. One-hundred and thirty-one out of 432 MALDI-TOF MS analyses (30%) exhibited a score ≥ 1.7. The performance of the technique varied across Candida species. Factors associated with a successful identification were the use of a chromogenic Candida medium and the time points 4 and 5 h. Using the factors 'chromogenic Candida medium' and time point 5 h the global performance of identification reached 60% and a mean MALDI-TOF score of 1.78. Identifying yeasts after a short-term incubation on a solid medium seems possible, especially when using a chromogenic Candida medium and respecting at least 5 h of incubation. This assay was a first step and needs to be completed using more strains, various chromogenic Candida medium and maybe also testing a longer culture time such as 6 h., (© 2019 APMIS. Published by John Wiley & Sons Ltd.)

Background: The salt-tolerant yeast strain Candida versatilis is usually added to high-salt, liquid-state soy sauce fermentation. The genome of C. versatilis was sequenced in our previous study but the reason for its high-osmolarity ability was not clear., Results: The 9.7 Mbp genome of C. versatilis contained 4711 CDS. Candida versatilis was the closest to another yeast, Zygosaccharomyces rouxii, added to soy sauce fermentation. The protein sequence of the whole genome was divided into 4338 groups, accounting for 92.1% of all the predicted protein of C. versatilis using OrthoMCL. Mitogen-activated protein kinase (MAPK) signal pathways, including high osmolarity and cell integrity, were predicted and proved by investigating the expression changes of the key genes CvHOG1, CvGPD1, and CvFPS1 in a high osmotic environment and by testing the variations of intracellular glycerol and extracellular glycerol., Conclusion: Candida versatilis exhibited strong osmotolerance because it could synthesize intracellular glycerol and absorb glycerol from the environment cooperated with the shut down of glycerol efflux channel in membrane. © 2018 Society of Chemical Industry., (© 2018 Society of Chemical Industry.)

In recent years, the fast and accurate identification of the Candida species is of great importance as the response to antifungal treatment differs among species. Following the treatment of several immunosuppressive diseases, fungal infections can emerge. The aim of this study was to compare the accuracy, costs and time of result periods of the methods used in the identification of the most common human fungal infectious agent, Candida strains. From various clinical samples sent to the Microbiology Laboratory of Karabuk University Training and Research Hospital between July 2016-December 2017, a total of 91 yeast isolates cultivated in blood agar (Becton Dickinson, USA) and/or Sabouraud dextrose agar (SDA-Oxoid, UK), confirmed with colony morphology and microscopic appearance, identified as Candida species with a fully automated identification system (Phoenix™ Yeast ID Panel, Becton Dickinson Diagnostics, USA) were included in the study. All the samples were examined with sequence analysis using ITS1 forward 5'-TCC GTA GGT GAA CCT GCG G-3' and ITS4 reverse 5'-TCC TCC GCT TAT TGA TAT GC-3' primers (Iontek, Turkey) and the matrix-assisted laser desorption-ionisation time of flight mass spectrometry (MALDI TOF-MS) systems. Molecular sequence analysis was accepted as the gold standard method and the results were compared with those of the other methods MALDI TOF-MS and Phoenix™ Yeast ID Panel in respect of the accuracy of the identification of Candida strains. According to the results of the DNA sequence analysis of the 91 Candida isolates included in the study, 24 were identified as Candida albicans, 20 Candida tropicalis, 16 Candida parapsilosis, 13 Candida glabrata, seven Candida kefyr, six Candida krusei, two of each Candida dubliniensis, Candida guilliermondi and one Candida lusitaniae. Compared to the results of the DNA sequence analysis, the accurate identification of the fully automated Phoenix™ system and the MALDI TOF-MS system was found as 92.3% and 97.8%, respectively. In addition to accuracy, costs and time of result periods of the three methods were also compared. Disregarding the cost of the device in the 3 methods, when the comparison was made of the cost per test and the time to results after pure production in SDA agar, the MALDI TOF-MS system was determined to have the lowest costs and provided results in the shortest time. As some of the Candida strains have antifungal resistance, identification of the strains must be a priority in respect of starting early treatment. The MALDI TOF-MS system has high performance in accurate identification, low costs and the system provides the results within minutes, thereby allowing immediate decision to be made for the antifungal treatment to be started. Thus, the morbidity, mortality and cost rates will be reduced. In conclusion, as the MALDI TOF-MS is a rapid, reliable and low cost per test system, it can be considered suitable for routine use in laboratories.

In this paper we analyze an experiment for the use of low-cost gas sensors intended to detect bacteria in wounds using a non-intrusive technique. Seven different genera/species of microbes tend to be present in most wound infections. Detection of these bacteria usually requires sample and laboratory testing which is costly, inconvenient and time-consuming. The validation processes for these sensors with nineteen types of microbes (1 Candida , 2 Enterococcus , 6 Staphylococcus , 1 Aeromonas , 1 Micrococcus , 2 E. coli and 6 Pseudomonas ) are presented here, in which four sensors were evaluated: TGS-826 used for ammonia and amines, MQ-3 used for alcohol detection, MQ-135 for CO₂ and MQ-138 for acetone detection. Validation was undertaken by studying the behavior of the sensors at different distances and gas concentrations. Preliminary results with liquid cultures of 10⁸ CFU/mL and solid cultures of 10⁸ CFU/cm 2 of the 6 Pseudomonas aeruginosa strains revealed that the four gas sensors showed a response at a height of 5 mm. The ammonia detection response of the TGS-826 to Pseudomonas showed the highest responses for the experimental samples over the background signals, with a difference between the values ​​of up to 60 units in the solid samples and the most consistent and constant values. This could suggest that this sensor is a good detector of Pseudomonas aeruginosa , and the recording made of its values ​​could be indicative of the detection of this species. All the species revealed similar CO₂ emission and a high response rate with acetone for Micrococcus , Aeromonas and Staphylococcus ., Competing Interests: The authors declare that there are no conflicts of interest.

Mitochondrial single-stranded DNA (ssDNA)-binding proteins (mtSSBs) are required for mitochondrial DNA replication and stability and are generally assumed to form homotetramers, and this species is proposed to be the one active for ssDNA binding. However, we recently reported that the mtSSB from Saccharomyces cerevisiae ( Sc Rim1) forms homotetramers at high protein concentrations, whereas at low protein concentrations, it dissociates into dimers that bind ssDNA with high affinity. In this work, using a combination of analytical ultracentrifugation techniques and DNA binding experiments with fluorescently labeled DNA oligonucleotides, we tested whether the ability of Sc Rim1 to form dimers is unique among mtSSBs. Although human mtSSBs and those from Schizosaccharomyces pombe , Xenopus laevis , and Xenopus tropicalis formed stable homotetramers, the mtSSBs from Candida albicans and Candida parapsilosis formed stable homodimers. Moreover, the mtSSBs from Candida nivariensis and Candida castellii formed tetramers at high protein concentrations, whereas at low protein concentrations, they formed dimers, as did Sc Rim1. Mutational studies revealed that the ability to form either stable tetramers or dimers depended on a complex interplay of more than one amino acid at the dimer-dimer interface and the C-terminal unstructured tail. In conclusion, our findings indicate that mtSSBs can adopt different oligomeric states, ranging from stable tetramers to stable dimers, and suggest that a dimer of mtSSB may be a physiologically relevant species that binds to ssDNA in some yeast species., (© 2019 Singh et al.)

Occurrence of non- Candida albicans Candida (NCAC) species that are associated with elevated MIC values and therapeutic failures are increasing. As a result, timely and accurate means of identification to the species level is becoming an essential part of diagnostic practices in clinical settings. In this study, 301 clinically isolated yeast strains recovered from various anatomical sites [Blood ( n = 145), other sites ( n = 156)] were used to assess the accuracy and practicality of API 20C AUX and 21-plex PCR compared to MALDI-TOF MS and large subunit rDNA (LSU rDNA). MALDI-TOF MS correctly identified 98.33% of yeast isolates, 100% of top five Candida species, 95.7% of rare yeast species, while 1.3% of isolates were misidentified. API 20C AUX correctly identified 83.7% of yeast isolates, 97.2% of top five Candida species, 61.8% of rare yeast species, while 16.2% of yeast isolates were misidentified. The 21-plex PCR, accurately identified 87.3% of yeast isolates, 100% of top five Candida species, 72% of rare yeast species, but it misidentified 1.3% of rare yeast species while 9.9% of whole yeast isolates were not identified. The combination of rapidity of 21-plex PCR and comprehensiveness of API 20C AUX, led to correct identification of 92% of included yeast isolates. Due to expensiveness of MALDI-TOF MS and sequencing, this combination strategy could be the most accurate and inexpensive alternative identification strategy for developing countries. Moreover, by the advent and development of cost-effective, reliable, and rapid PCR machines that cost 130 US dollars, 21-plex could be integrated in routine laboratories of developing and resource-limited countries to specifically identify 95% causative agents of yeast-related infections in human. Databases of MALDI-TOF MS, API 20C AUX, and the number of target species identified by 21-plex require further improvement to keep up with the diverse spectrum of yeast species.

Kaoliang is a refreshing fragranced type of Chinese spirits with slight apple fragrance that comes from ethyl acetate (EA). Special aromas are produced by esterification microorganisms, which affect the taste and quality of the wine. In this study, new yeast strains were isolated from yellow water, a by-product during fermentation process. Meanwhile, the optimal culture condition was determined for its growth and EA production. Three new strains, Kazachstaniaexigua, Candida humilis and Saccharomyces cerevisiae were identified from yellow water. Among these strains, S. cerevisiae S5 was the new and dominant strain. Results from response surface methodology showed that S. cerevisiae S5 produced 161.88 ppm of EA, in the medium with 4.91% yeast extract, 9.82% peptone, and 20.91% glucose after 96 hours of cultivation at 27.53°C. GC analysis showed that aroma compounds, such as EA, isoamyl acetate and 2-phenylethanol increased from the sample of optimal condition when compared to the one from initial fermentation condition., Competing Interests: The authors have declared that no competing interests exist.

Brettanomyces bruxellensis negatively impacts on the sensorial quality of wine by producing phenolic compounds associated with unpleasant odors. Thus, the control of this spoilage yeast is a critical factor during the winemaking process. A recent approach used to biocontrol undesired microorganisms is the use of yeast released antimicrobial peptides (AMPs), but this strategy has been poorly applied to wine-related microorganisms. The aim of this study was to evaluate the antifungal capacity of Candida intermedia LAMAP1790 against wine-spoilage strains of B. bruxellensis and fermentative strains of Saccharomyces cerevisiae, and also to determine the chemical nature of the compound. The exposure of strains to the supernatant of C. intermedia saturated cultures showed antifungal activity against B. bruxellensis, without affecting the growth of S. cerevisiae. By fractionation and concentration of C. intermedia supernatants, it was determined that the antifungal activity was related to the presence of heat-labile peptides with molecular masses under 5 kDa. To our knowledge, this is the first report of AMPs secreted by C. intermedia that control B. bruxellensis. This could lead to the development of new biocontrol strategies against this wine-spoilage yeast.

Objectives: Sophorolipids (SLs) are a group of surface-active glycolipids produced by a type of nonpathogenic yeast Candida bombicola in the presence of vegetable oil through fermentation technology. SLs have shown antitumor activity; however, the mechanism of action underlying the anticancer activity of SLs is poorly understood. This work evaluated the anticancer activity of SLs fermented from palm oil by exploring its antiangiogenic activity., Materials and Methods: The SLs that were fermented and further characterized for their biochemical activities. Cytotoxicity study was performed to assess cytostatic properties. A series of in vitro and ex vivo angiogenesis assay was also carried out. The relative fold change in the expression of p53 mRNA by SLs was also studied., Results: Altogether, the data show that SLs derived from palm oil fermentation process inhibited neovascularization in the ex vivo tissue segments and also the endothelial cell proliferation between 50% and 65% inhibition as a whole. The palm oil derived SLs also caused downregulation of the suppression level of vascular endothelial growth factor and also upregulate the p53 mRNA level. The analytical studies revealed the presence of high amount of phenolic compounds but with relatively weak antioxidant activity. The gas chromatography-mass spectrometry studies revealed abundant amount of palmitic and oleic acid, the latter an established antiangiogenic agent, and the former being proangiogenic., Conclusion: Therefore, it can be concluded from this study that SLs derived from fermented palm oil have potent antiangiogenic activity which may be attributed by its oleic acid component., Competing Interests: There are no conflicts of interest.

This article discusses the effect of selenium in aqueous solutions on aspects of lipid and amino acid metabolism in the cell biomass of Saccharomyces cerevisiae MYA-2200 and Candida utilis ATCC 9950 yeasts. The yeast biomass was obtained by using waste products (potato wastewater and glycerol). Selenium, at a dose of 20 mg/L of aqueous solution, affected the differentiation of cellular morphology. Yeast enriched with selenium was characterized by a large functional diversity in terms of protein and amino acid content. The protein content in the biomass of S. cerevisiae enriched with selenium (42.6%) decreased slightly as compared to that in the control sample without additional selenium supplementation (48.4%). Moreover, yeasts of both strains enriched with selenium contained a large amount of glutamic acid, aspartic acid, lysine, and leucine. Analysis of fatty acid profiles in S. cerevisiae yeast supplemented with selenium showed an increase in the unsaturated fatty acid content (e.g., C18:1). The presence of margaric acid (C17:0) and hexadecanoic acid (C17:1) was found in the C. utilis biomass enriched with selenium, in contrast to that of S. cerevisiae. These results indicate that selenium may induce lipid peroxidation, which consequently affects the loss of integrity of the cytoplasmic membrane. Yeast enriched with selenium with optimal amino acid and lipid composition can be used to prepare a novel formula of dietary supplements, which can be applied directly to various diets for both humans and animals.

Cell wall mannan of the pathogenic yeast Candida krusei was prepared using the antibiotic Benanomicin A, which has a lectin-like function. The chemical structure of this molecule was found to be similar to that of mannan prepared from the same yeast by the conventional method using Fehling reagent. Only a few degradation products were detected when the mannan prepared using Fehling reagent was subjected to alkali treatment (β-elimination), but multiple α-1,2-linked oligosaccharides were detected when the mannan purified with Benanomicin A was treated with alkali. These results indicate that most of the O -linked sugar chains in mannan were lost under conventional conditions when exposed to the strongly alkaline Fehling reagent. In contrast, the O -glycosidic bond in mannan was not cleaved and the O -linked sugar chains were maintained and almost intact following treatment with the mild novel preparation method using Benanomicin A. Therefore, we argue that the new mannan preparation method using Benanomicin A is superior to conventional methods. In addition, our study suggests that some yeast mannans, whose overall structure has already been reported, may contain more O -linked sugar chains than previously recognized.

The present study aimed to evaluate the incidence of candidemia, the trend of species distribution and the antifungal susceptibility patterns of all invasive strains of Candida spp. isolated over a 6-year period in an Eastern European University hospital. A total number of 156 isolates were reidentified by MALDI-TOF and tested for susceptibility by Sensititre TM YeastOne™. Isolates were assigned as non-susceptible or belonging to the wild type according to the new CLSI (2017, 2018) break points and epidemiological cut-off values. C. parapsilosis (37.82%) was the most frequently isolated yeast, followed by C. albicans (26.28%). The general tendency of the species distribution during the surveyed period shifted towards an increase in C. parapsilosis and C. lusitaniae isolates. Fluconazole resistance was present in 23.52% of C. glabrata, 5.08% of C. parapsilosis and in none of the C. albicans, C. tropicalis and C. lusitaniae isolates. Echinocandin resistance was present only in 1(5.88%) C. glabrata isolate. The study emphasises the importance of monitoring local epidemiologic data and antifungal susceptibility trends due to the diversity of affected patient groups in our hospital.

Background: Screening for Aspergillus (Asp-AG) and Candida antigen (Ca-AG) with immunoassays is established for stem cell recipients at high risk for invasive fungal infections (IFI). While parenteral nutrition (PN) will be applied in case of complications leading to insufficient alimentation, piperacillin-tazobactam (TZP) is started at the onset of febrile neutropenia., Objectives: The aim of this study was to investigate drug-laboratory interactions between PN and TZP and both immunoassays which could affect the specificity of the assays and lead to the false assumption of an IFI., Methods: Batches of TZP and PN were tested with both assays in vitro. In total, 380 samples of 83 batches were analysed., Results: None of the examined preparations were tested positive with Asp-AG assay. Measurable amounts of Ca-AG were detected in a lipid emulsion, two different trace element supplements, a fat-soluble vitamin preparation and all tested brands of TZP., Conclusions: We conclude that false positivity of Asp-AG assay due to TZP and PN does not occur. Cross reactions with Ca-AG assay have been detected in some preparations. The in vivo relevance of Ca-AG positivity has to be reviewed in further studies considering an effect of dilution. Physicians should be aware of a possible cross reaction with Ca-AG assays which could lead to false-positive results., (© 2018 Blackwell Verlag GmbH.)

Dendritic cells (DCs) abundantly express diverse receptors to recognize mannans in the outer surface of Candida cell wall, and these interactions dictate the host immune responses that determine disease outcomes. C. krusei prevalence in candidiasis worldwide has increased since this pathogen has developed multidrug resistance. However, little is known how the immune system responds to C. krusei. Particularly, the molecular mechanisms of the interplay between C. krusei mannan and DCs remain to be elucidated. We investigated how C. krusei mannan affected DC responses in comparison to C. albicans, C. tropicalis and C. glabrata mannan. Our results showed that only C. krusei mannan induced massive cytokine responses in DCs, and led to apoptosis. Although C. krusei mannan-activated DCs underwent apoptosis, they were still capable of initiating Th17 response. C. krusei mannan-mediated DC apoptosis was obligated to the TLR2 and MyD88 pathway. These pathways also controlled Th1/Th17 switching possibly by virtue of the production of the polarizing cytokines IL-12 and IL-6 by the C. krusei mannan activated-DCs. Our study suggests that TLR2 and MyD88 pathway in DCs are dominant for C. krusei mannan recognition, which differs from the previous reports showing a crucial role of C-type lectin receptors in Candida mannan sensing.

Low cell tolerance is a basic issue in high-glucose fermentation under high temperature to economically obtain high product titer. Candida glycerinogenes, an industrial yeast, has excellent tolerance to the combined heat and high-glucose stress than Saccharomycescerevisiae. The potential mechanism responsible for the high tolerance was illustrated here. The transcription of the potential stress-responsive genes in two strains were varied under single stress (heat or high-glucose), especially the ribosome-related genes. Unlike S. cerevisiae, C. glycerinogenes up-regulated 17 genes, including most of the single stress responsive genes, and genes Avt1 and Pfk1 under the combined stress, indicating a more systematic stress-responsive system in C. glycerinogenes. Further down-regulating the 17 potential key responsive genes indicated that genes Dip5, Gpd1, Pfk1, Hxt4, Hxt6, and Ino4 are important for cell tolerance to the combined stress. Furthermore, most of the ribosomal function related genes, such as Mrt4, Nug1, Nop53, Rpa190, Rex4, and Nsr1, play important role in cell tolerance. Therefore, the wider responsive gene spectrum and the activated expression of ribosomal function related genes might be key and prerequisite factors for the excellent tolerance to the combined stress of C. glycerinogenes., (Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Candida auris is a multidrug-resistant pathogenic yeast whose recent emergence is of increasing public-health concern. C. auris can colonise multiple body sites, including patients' skin, and survive for weeks in the health care environment, facilitating patient-to-patient transmission and fueling health care-associated outbreaks. Rapid and accurate detection of C. auris colonisation is essential for timely implementation of infection control measures and to prevent transmission. Currently, axilla/groin composite swabs, used to assess colonisation status, are processed using a culture-based method that is sensitive and specific but requires 14 days. This delay limits the opportunity to respond and highlights the need for a faster alternative. The culture-independent T2 Magnetic Resonance (T2MR) system is a rapid diagnostic platform shown to detect target pathogens of interest from unprocessed blood samples in <5 hours. In this study, a new C. auris-specific T2 assay was evaluated for screening of the skin surveillance samples. Inclusivity and limit of detection of the T2 C.  auris assay were assessed with spiked samples in a representative skin flora background. The T2 C. auris assay recognised isolates from each of the 4 known clades of C. auris and consistently detected cells at 5 CFU/mL. Finally, 89 clinical axilla/groin swab samples were processed with the T2 C. auris assay. The culture-based diagnostic assay was used as a gold standard to determine performance statistics including sensitivity (0.89) and specificity (0.98). Overall, the T2 C. auris assay performed well as a rapid diagnostic and could help expedite the detection of C. auris in patient skin swabs., (Published 2018. This article is a U.S. Government work and is in the public domain in the USA.)

Candida-related infections have become a major problem in hospitals. The species identification of yeast is the prerequisite for the initiation of adequate antifungal therapy. In the present study, the connection between inherent UV resonance Raman (RR) spectral profiles of Candida species and taxonomic differences was investigated for the first time. UV RR in combination with statistical modeling was applied to extract taxonomic information from the spectral fingerprints for subsequent differentiation. The identification accuracies of independent batch cultures were determined by applying a leave-one-batch-out cross validation. The quality of differentiation can be divided into three levels. Within a defined taxonomic group comprising the species C. glabrata, C. guilliermondii, and C. haemulonii, the identification accuracy was low. On the next level, the identification results of C. albicans and C. tropicalis were characterized by high sensitivities of 98 and 95% but simultaneously challenged by false-positive predictions due to the misallocation of C. spherica (as C. albicans) and C. viswanathii (as C. tropicalis). The highest level of identification accuracies was reached for the species C. dubliniensis, C. krusei, C. africana, C. novergica, and C. parapsilosis. Reliable identification results were observed with accuracies ranging from 93 up to 100%. The species allocation based on the UV RR spectral profiles could be reproduced by the identification of independent batch cultures. We conclude that the introduced spectroscopic approach is capable of transforming the high-dimensional UV RR data of Candida species into clinically useful decision parameters. Graphical abstract.

The incidence of candidemia caused by Candida albicans and Candida glabrata is constantly increasing and is accompanied by the rising use of the few available antifungals. The widespread use of echinocandins and azoles for the treatment of invasive candidemia has enhanced the development of antifungal resistance, resulting in an increasing health care problem. Hence, the rapid detection of resistant strains is required. This study aimed to evaluate the detection of C. albicans and C. glabrata strains resistant to caspofungin by the matrix-assisted laser desorption ionization Biotyper antibiotic susceptibility test rapid assay (MBT ASTRA). This novel semiquantitative technique facilitates the detection of caspofungin-resistant strains within 6 h. MBT ASTRA results were compared to the data obtained by the use of Clinical and Laboratory Standards Institute (CLSI) guidelines. Clinical isolates of C. albicans ( n = 58) and C. glabrata ( n = 57) were analyzed by MBT ASTRA and the CLSI microdilution method. Antifungal susceptibility testing against caspofungin by the CLSI microdilution method classified the C. albicans isolates into 36 susceptible and 22 resistant strains and the C. glabrata isolates into 5 susceptible, 33 resistant, and 19 intermediate strains. For C. albicans , the comparison of MBT ASTRA and the CLSI method revealed an excellent categorical agreement of 100%. A sensitivity and a specificity between MBT ASTRA and the CLSI microdilution method of 94% and 80%, respectively, were detected for C. glabrata strains, based on categorical agreement. In conclusion, the results obtained by MBT ASTRA indicate that this is a very promising approach for the rapid detection of Candida isolates resistant to caspofungin., (Copyright © 2018 American Society for Microbiology.)

As a promising biolabeling biomaterials, quantum dots (QDs) present a great potential. However, the toxicity of QDs to organisms has attracted wide attention. In our research, we introduced an in vitro method to study the molecular mechanisms for the structure and activity alterations of Candida rugosa lipase (CRL) with the binding of 3-mercaptopropionic acid-capped CdTe QDs. Multiple spectroscopic methods, isothermal titration calorimetry, and enzyme activity measurements were used in this paper. QDs statically quenched the intrinsic fluorescence of CRL with the quenching constant decreases from 2.46 × 10 13 to 1.64 × 10 13  L mol -1  second -1 (298 to 310 K). It binds to CRL through hydrophobic force with 1 binding site, unfolding and loosening the skeleton and changed its secondary structure. Rather than aggregating on the surface, it enters the pocket of the CRL to interact with Ser-209 (2.43 Å) and the residues surrounding Ser-209, making the catalytic triad more exposed. Furthermore, the activity of CRL was inhibited by approximately 15%. This work demonstrates that 3-mercaptopropionic acid-capped CdTe QDs may cause negative effects to CRL and obtains a molecular mechanism on QD-induced toxicity to proteins in vitro., (Copyright © 2018 John Wiley & Sons, Ltd.)

Trichophyton rubrum and Candida species comprise the majority of onychomycosis pathogens. The aim of this study was to evaluate Raman spectroscopy for the differentiation between healthy and either T. rubrum or Candida infected nails. Raman measurements were performed on clippings (N = 52) infected either by T. rubrum (N = 12) or Candida species (N = 14; C. parapsilosis (sensu lato): N = 11, C. glabrata: N = 1, C. albicans: N = 2) with healthy nails (N = 26) used as controls. Systematic spectral differences were observed in the 500-520 cm-1 band region, attributable to a diverting imprint of the disulfide stretching of cystine and cysteine residues among samples. Particularly, Candida infected nails demonstrated a shoulder at 519 cm-1, corresponding to the signal of the less stable gauche-gauche-trans conformation of the disulfide bond. Two additional bands at 619 and 648 cm-1, corresponding to the C-S stretching vibration, were more evident in the T. rubrum infected nails. Finally, a Raman band at 1550 cm-1, attributable to amide II and tryptophan (Trp) content, was undetectable in Candida infected nails. Using principal component analysis (PCA), efficient differentiation of healthy, T. rubrum and Candida species infected nails was achieved. Soft independent modeling of class analogy (SIMCA) and partial least squares-discriminant analysis (PLS-DA) were further applied to generate diagnostic algorithms for the classification of Raman spectra. Both techniques succeeded in modeling clinical nail samples in three groups according to their mycological categories. Raman spectroscopy is a promising method for the differentiation of healthy vs. diseased nails, including efficient differentiation between onychomycosis caused by T. rubrum and Candida species.

Waterways are popular locations for the disposition of criminal evidence because the recovery of latent fingerprints from such evidence is difficult. Currently, small particle reagent is a method often used to visualize latent fingerprints containing carcinogenic and hazardous compounds. This study proposes an eco-friendly, safranin-tinted Candida rugosa lipase (triacylglycerol ester hydrolysis EC 3.1.1.3) with functionalized carbon nanotubes (CRL-MWCNTS/GA/SAF) as an alternative reagent to the small particle reagent. The CRL-MWCNTS/GA/SAF reagent was compared with the small particle reagent to visualize groomed, full fingerprints deposited on stainless steel knives which were immersed in a natural outdoor pond for 30 days. The quality of visualized fingerprints using the new reagent was similar (modified-Centre for Applied Science and Technology grade: 4; p > 0.05) to small particle reagent, even after 15 days of immersion. Despite the slight decrease in quality of visualized fingerprints using the CRL-MWCNTS/GA/SAF on the last three immersion periods, the fingerprints remained forensically identifiable (modified-Centre for Applied Science and Technology grade: 3). The possible chemical interactions that enabled successful visualization is also discussed. Thus, this novel reagent may provide a relatively greener alternative for the visualization of latent fingerprints on immersed non-porous objects.

Objective: Neutrophil extracellular traps (NETs) are peculiar structures composed of the externalized chromatin with intracellular proteins and formed by activated neutrophils in a reactive oxygen species (ROS)-dependent manner. Aberrant NETs are considered to be autoantigens for anti-neutrophil cytoplasmic antibodies (ANCAs) underling the development of microscopic polyangiitis (MPA). However, little is known regarding the therapeutic efficacy of in vivo inhibition of NET formation (NETosis) on MPA pathogenesis. This study determines whether reducing NETosis prevents ANCA production and improves characteristic involvement., Methods: A mouse model of MPA induced by administering a novel extract from Candida albicans was devised. By applying this method to mice lacking phosphoinositide 3-kinase gamma (PI3K-gamma), which is indispensable for ROS production in neutrophils, we investigated the levels of in vivo NETs, ANCA titers and histological damage., Results: Our model exhibited accumulation of NETs in vivo, elevation of ANCA titers and characteristic pathologies mimicking human MPA, including small-vessel vasculitis and crescentic glomerulonephritis. Strikingly, these abnormalities were reduced by genetically and/or pharmacologically blocking PI3K-gamma. Moreover, a pharmacological PI3K-gamma blockade decreased the levels of human NETs., Conclusion: Our results suggest that in vivo inhibition of NETosis by blocking PI3K-gamma could be a promising therapeutic strategy for the pathogenesis of MPA.

Candida antarctica lipase B is stabilized in a porous, high internal phase emulsion (HIPE) of polydicyclopentadiene to enable biocatalytic waste stream upcycling. The immobilized lipase is subjected to thorough washing conditions and tested for stability in extreme environments and reusability. A porous internal microstructure is revealed through scanning electron microscopy. After preparation, lipase activity increased to 139 ± 9.7% of its original activity. After 10 cycles of reuse, immobilized lipase retains over 50% activity. Immobilized lipase retains activity after 24 h of exposure to temperatures ranging from 20 to 60 °C and pH values of 3, 7, and 10. In the most extreme environments tested, lipase retained 42.8 ± 21% relative activity after exposure to 60 °C and 49.4 ± 16% relative activity after exposure to pH 3. Polymerized HIPEs stabilize lipase and, thus, extend its working range. Further synthesis optimization has the potential to increase enzyme stability, immobilization efficiency, and uniformity. The reported hierarchical stabilization technique shows promise for use of immobilized lipase in non-ideal, industrially relevant conditions.

Candida biofilms resist the effects of available antifungal therapies. Prior studies with Candida albicans biofilms show that an extracellular matrix mannan-glucan complex (MGCx) contributes to antifungal sequestration, leading to drug resistance. Here we implement biochemical, pharmacological, and genetic approaches to explore a similar mechanism of resistance for the three most common clinically encountered non- albicans Candida species (NAC). Our findings reveal that each Candida species biofilm synthesizes a mannan-glucan complex and that the antifungal-protective function of this complex is conserved. Structural similarities extended primarily to the polysaccharide backbone (α-1,6-mannan and β-1,6-glucan). Surprisingly, biochemical analysis uncovered stark differences in the branching side chains of the MGCx among the species. Consistent with the structural analysis, similarities in the genetic control of MGCx production for each Candida species also appeared limited to the synthesis of the polysaccharide backbone. Each species appears to employ a unique subset of modification enzymes for MGCx synthesis, likely accounting for the observed side chain diversity. Our results argue for the conservation of matrix function among Candida spp. While biogenesis is preserved at the level of the mannan-glucan complex backbone, divergence emerges for construction of branching side chains. Thus, the MGCx backbone represents an ideal drug target for effective pan- Candida species biofilm therapy. IMPORTANCE Candida species, the most common fungal pathogens, frequently grow as a biofilm. These adherent communities tolerate extremely high concentrations of antifungal agents, due in large part, to a protective extracellular matrix. The present studies define the structural, functional, and genetic similarities and differences in the biofilm matrix from the four most common Candida species. Each species synthesizes an extracellular mannan-glucan complex (MGCx) which contributes to sequestration of antifungal drug, shielding the fungus from this external assault. Synthesis of a common polysaccharide backbone appears conserved. However, subtle structural differences in the branching side chains likely rely upon unique modification enzymes, which are species specific. Our findings identify MGCx backbone synthesis as a potential pan- Candida biofilm therapeutic target., (Copyright © 2018 Dominguez et al.)

β-glucan is widely distributed in nature as water soluble and insoluble forms. Both forms of β-glucan are utilized in several fields, especially for functional foods. Yeast β-glucan is a medically important insoluble particle. Solubilization of yeast β-glucan may be valuable for improving functional foods and in medicinal industries. In the present study, we applied an acid degradation method to solubilize yeast β-glucan and found that β-glucan was effectively solubilized to low-molecular weight β-glucans by 45% sulfuric acid treatment at 20°C. The acid-degraded soluble yeast β-glucan (ad-sBBG) was further fractionated into a higher-molecular weight fraction (ad-sBBG-high) and a lower-molecular weight fraction (ad-sBBG-low). Since ad-sBBG-high contained mannan, while ad-sBBG-low contained it only scarcely, it was possible to prepare low-molecular weight soluble β-glucan with higher purity. In addition, ad-sBBG-low bound to dectin-1, which is an innate immunity receptor of β-glucan, and showed antagonistic activity against reactive oxygen production and cytokine synthesis by macrophages. Thus, this acid degradation method is an important procedure for generating immune-modulating, low-molecular weight, soluble yeast β-glucan., (Copyright © 2017 Elsevier B.V. All rights reserved.)