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Malassezia, the most abundant fungal commensal on the mammalian skin, has been linked to several inflammatory skin diseases such as atopic dermatitis, seborrheic dermatitis and psoriasis. This study reveals that epicutaneous application with Malassezia globosa (M. globosa) triggers skin inflammation in mice. RNA-sequencing of the resulting mouse lesions indicates activation of Interleukin-17 (IL-17) signaling and T helper 17 (Th17) cells differentiation pathways by M. globosa. Furthermore, our findings demonstrate a significant upregulation of IL-23, IL-23R, IL-17A, and IL-22 expressions, along with an increase in the proportion of Th17 and pathogenic Th17 cells in mouse skin exposed to M. globosa. In vitro experiments illustrate that M. globosa prompts human primary keratinocytes to secrete IL-23 via TLR2/MyD88/NF-κB signaling. This IL-23 secretion by keratinocytes is shown to be adequate for inducing the differentiation of pathogenic Th17 cells in the skin. Overall, these results underscore the significant role of Malassezia in exacerbating skin inflammation by stimulating IL-23 secretion by keratinocytes and promoting the differentiation of pathogenic Th17 cells. [ABSTRACT FROM AUTHOR]

Background and Purpose: Species identification of Malassezia using culture-dependent methods is time-consuming due to their fastidious growth requirements. This study aimed to evaluate a rapid and accurate molecular method in order to diagnose the pityriasis versicolor (PV) and identify Malassezia species from direct clinical samples.Materils and Methods: Skin scraping or tape samples from patients with PV and healthy volunteers as the control group were collected. Diagnosis of PV was confirmed by direct microscopic examination. The DNA extraction was performed according to the steel bullet beating method. Polymerase chain reaction-restriction fragment length polymorphism assay using HhaI restriction enzyme was applied for the identification and differentiation of Malassezia species.Results: The PCR method was able to detect Malassezia in 92.1% of specimens which were also confirmed with microscopic examination. Statistically, a significant association was observed between the results of the two assays (P ˂ 0.001). Moderate agreement was identified between the two methods to diagnose the PV in both populations (Kappa: 0.55). Considering microscopic examination as the gold standard method for confirmation of PV, the sensitivity, specificity, positive predictive value, and negative predictive value values of the PCR assay for recognition of PV were 85%, 75%, 92%, and 60%, respectively. M. globosa and M. restricta were the most prevalent species isolated from patients.Conclusion: In this study, the two-step molecular method based on the amplification of the D1/D2 domain and digestion of the PCR product by one restriction enzyme was able to diagnose and identify Malassezia directly from clinical samples. Consequently, it can be said that the molecular-based method provides more facilities to identify fastidious species, such as M. restricta.

• Commensals transit as pathogens, associated with dermatological conditions. • Targeted specific enzyme exists only in pathogen metabolic pathway. • Phytoconstituents inducing the antifungal activity signifies the remedy. • Computational approaches ascertain the prominent compound against the target. The fungus Malassezia globosa is often responsible for superficial mycoses posing significant treatment challenges because of the unfavourable side effects of available antifungal drugs. To reduce potential hazards to the host and overcome these hurdles, new therapeutic medicines must be developed that selectively target enzymes unique to the pathogen. This study focuses on the enzyme anthranilate phosphoribosyltransferase (AnPRT), which is vital to M. globosa 's tryptophan production pathway. To learn more about the function of the AnPRT enzyme, we modeled, validated, and simulated its structure. Moreover, many bioactive components were found in different extracts from the plant Albizia amara after phytochemical screening. Interestingly, at doses ranging from 500 to 2000 µg/ml, the chloroform extract showed significant antifungal activity, with inhibition zones measured between 11.0 ± 0.0 and 25.6 ± 0.6 mm. According to molecular docking analyses, the compounds from the active extract, particularly 2-tert-Butyl-4-isopropyl-5-methylphenol, interacted with the AnPRT enzyme's critical residues, ARG 205 and PHE 214, with an effective binding energy of -4.9 kcal/mol. The extract's revealed component satisfies the requirements for drug-likeness and shows promise as a strong antifungal agent against infections caused by M. globosa. These findings imply that using plant-derived chemicals to target the AnPRT enzyme is a viable path for the creation of innovative antifungal treatments. [ABSTRACT FROM AUTHOR]

Although the fungal microbiome in human skin mainly comprises lipophilic yeasts, including Malassezia species, these microorganisms can cause various dermatitis conditions, including pityriasis versicolor, seborrheic dermatitis, folliculitis, and atopic dermatitis, depending on the host condition. Both Malassezia globosa and Malassezia restricta are major species implicated in Malassezia-related dermatitis. However, the pathogenicity of these microorganisms has not been revealed at the genetic level owing to the lack of a genetic recombination system. Therefore, we developed a gene recombination system for M. globosa using Agrobacterium tumefaciens-mediated gene transfer of the target gene FKB1, which encodes the FKBP12 protein that binds the calcineurin inhibitor tacrolimus. The wild-type strain of M. globosa was sensitive to tacrolimus, whereas the FKB1 deletion mutant was resistant to tacrolimus. Reintroduction of FKB1 into the FKB1 deletion mutant restored wild-type levels of susceptibility to tacrolimus. Moreover, an FKB1-eGFP fusion gene was generated and expression of this fusion protein was observed in the cytoplasm. This newly developed gene recombination system for M. globosa will help further our understanding of the pathogenesis of M. globosa-related dermatitis at the genetic level. [ABSTRACT FROM AUTHOR]

Balanced skin microbiota is crucial for maintaining healthy normal skin function; however, disruption of the balance in skin microbiota is linked with skin diseases such as atopic dermatitis, acne vulgaris, dandruff, and candidiasis. Lactoplantibacillus species with proved with health benefits are probiotics that improve the balance of microbiome in skin and gut. In the present study, we investigated the potential antimicrobial activity of Lactiplantibacillus plantarum APsulloc 331261 (APsulloc 331261) and Lactiplantibacillus plantarum APsulloc 331266 (APsulloc 331266) derived from green tea, in inhibiting five skin pathogenic strains (Staphylococcus aureus (S. aureus), Cutibacterium acnes (C. acnes), Candia albicans (C. albicans), Malassezia globosa (M. globose), and Malassezia restricta (M. restricta)) associated with skin infection. Viability of S. aureus, C. acnes, C. albicans, M. globosa, and M. restricta was inhibited by indirect co-culture with APsulloc 331261 or APsulloc 331266 at various ratios. Different concentrations of the cell-free conditioned media (CM) derived from APsulloc 331261 or APsulloc 331266 inhibited the vaibility of S. aureus, C. acnes, C. albicans, M. globosa and M. restricta in a dose dependent manner. Moreover, susceptibility of S. aureus, C. acnes, and C. albicans against APsulloc 331261 or APsulloc 331266 was confirmed following agar overlay methods. Results of the agar overlay confirmed that various concentrations of APsulloc 331261 and APsulloc 331266 exhibited low to high inhibitory activity on the growth of S. aureus (ZDI 20.3 ± 2.1–32.3 ± 2.1 mm, R value 5.7 ± 0.8–7.8 ± 1.3 mm), C. acnes (ZDI 15.0 ± 1.7–22.2 ± 1.7 mm, R value 3.2 ± 1.3–5.5 ± 1.3 mm) and C. albicans (ZDI 13.3 ± 4.0–27.0 ± 3.6 mm, R value 2.8 ± 1.9–5.5 ± 1.7 mm). Finally, standard PCR analysis identified the presence of the of plantaricin genes encoding antimicrobial peptides in APsulloc 331261 and APsulloc 331266. These results suggest that APsulloc 331261 and APsulloc 331266 has a potential effect in the improvement of the balance of skin microbiota by inhibiting skin pathogenic strains.

Malassezia globosa is a commensal basidiomycetous yeast occurring on the skin that causes pityriasis versicolor (PV) and seborrheic dermatitis, but that has also been implicated in other dermatoses. Cinnamaldehyde (CM) has antibacterial, antioxidant, and anti-inflammatory activities, but the effect of CM on M. globosa -infected PV has not been clarified. The study aimed to investigate the possible antifungal and antibiofilm activities of CM against M. globosa -infected PV in vivo and in vitro. The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of CM against M. globosa. The crystal violet staining assay and XTT assay were used to investigate the inhibition of CM on biofilm formation and the eradication of mature biofilms. The visualizations of the biofilm and cell distribution in the biofilm matrix were performed with a scanning electron microscope and confocal laser scanning microscope. The kits of antioxidant kinase were used to determine the activities of oxidative stress markers in M. globosa -stimulated HaCaT cells. Western blot assays were used to evaluate the role of TLR2/NF-κB in vitro. Furthermore, the protective effect of CM was assessed in M. globosa -associated PV mice. The expressions of inflammatory cytokines and apoptosis were screened using ELISA assays. The expressions of interleukin-6 and tumor necrosis factor-α were measured by an immunohistochemistry method in vivo. Our results showed that the MIC of CM against planktonic cells of M. globosa was 4 µg/ml and treatment with 20 × MIC CM eradicated mature biofilms of M. globosa. In vitro , after CM treatment the levels of oxidative stress indicators (i.e., superoxide dismutase, catalase, glutathione) significantly increased, while the levels of malondialdehyde decreased. In addition, the expression of TLR2/NF-κB in HaCaT cells was significantly reduced after CM treatment. On the other hand, an in vivo therapeutic effect of CM was assessed against M. globosa -infected mice. The fungal load on the skin decreased after treatment with CM compared to the M. globosa- infected group. In addition, the uninfected animals showed a normal skin structure, whereas, the M. globosa -infected mice showed extensive infiltration of neutrophils in skin tissues that improved after treatment with CM. Meanwhile, the levels of inflammatory and apoptotic factors improved after CM treatment. Our results showed that CM inhibits the biofilm formation of M. globosa and eradicates mature biofilms of M. globosa. Treatment with CM significantly decreased oxidative stress, apoptosis, and inflammatory markers in the skin tissue and HaCaT cells. Hence, this study suggests that CM is a good candidate therapeutic agent against M. globosa -induced PV infections because of its antifungal, antibiofilm, and anti-inflammatory properties. [Display omitted] [ABSTRACT FROM AUTHOR]

Malassezia spp. are lipophilic fungi that are part of the normal flora of the human skin and are the etiological agents of dandruff and seborrheic dermatitis. β-Carbonic Anhydrases (CAs; EC 4.2.1.1) expressed from the pathogenic fungi are an alternative/complementary drug target. Previous work by our groups demonstrated that flavonoids and depsides can effectively inhibit Malassezia globosa β-CA (MgCA). In continuation of this study herein we report the inhibitory activity of a variety of phenols from Origanum dictamnus L. and Thymus vulgaris L. against β-MgCA, among them I4-II7-di-carvacrol, a new natural product. Structure elucidation of the compounds was performed by 1 D, 2 D NMR and spectrometric analyses. Xanthomicrol and rosmarinic acid were active in the (sub)micromolar range (KIS 0.6 and 2.2 μM, respectively vs 40.0 μM of the standard inhibitor acetazolamide). Finally, the compounds were not cytotoxic, but showed in vitro no activity against Malassezia furfur. [ABSTRACT FROM AUTHOR]

Objective: To establish a mouse model of atopic dermatitis (AD) with overgrowth Malassezia globosa. Methods: Eighteen BALB/c mice were randomly divided into the control group, AD group, NS/M group, AD+NS/M group, Oil/M group and AD+Oil/M group, 3 mice per group. AD model of BALB/c mice were established by topical administration of MC903. Fungi overgrowth experimental models were attempted to establish using suspension of M. globosa with olive oil and normal saline as vehicle, respectively. Clinical manifestations and lesion scoring as well as mycological and histopathological changes of each group were evaluated. Scanning and transmission electron microscopy were also used to observe the changes on hair follicle and hair shaft. Results: Compared with AD group, more severe AD-like lesion, obvious hair loss andincreasedlesion scoring (q=5.95, P

Glycosylphosphatidylinositols (GPI)-anchored proteins (GpiPs) are related to the cell wall biogenesis, adhesion, interactions, protease activity, mating, etc. These proteins have been identified in many organisms, including fungi such as Neurospora crassa, Candida albicans, Saccharomyces cerevisiae, and Fusarium graminearum. MGL-3153 gene of Malassezia globosa (M. globosa) encodes a protein which is homologous of the M. restricta, M. sympodialis, M. Pachydermatis, and U. maydis GpiPs. Real-time PCR assay showed that the expression of MGL_3153 gene was significantly up-regulated among M. globosa isolated from patients with pityriasis versicolor (PV) compared to a healthy individual, suggesting the contribution of this gene in the virulence of M. globosa. Accordingly, the sequence of this protein was analyzed by bioinformatics tools to evaluate the structure of that. The conservation analysis of MGL-3153 protein showed that the C-terminal region of this protein, which is responsible for GPI-anchor ligation, was highly conserved during evolution while the N-terminal region just conserved in Malassezia species. Moreover, the predicted tertiary structure of this protein by homology modeling showed that this protein almost has alpha helix structure and represented a stable structure during 150 ns of molecular dynamic simulation. Our results revealed that this protein potentially belongs to GPI-anchored proteins and may contribute to the virulence of M. globosa which warrants further investigations in this area. [ABSTRACT FROM AUTHOR]

Introduction. Malassezia globosa is a yeast species that belongs to the mycobiota of humans and animals, associated with dermatological disorders, such as dandruff. This is a chronic scalp skin disorder characterized by flaking and itching. Treatments include commercial shampoo with different formulations that contain antifungal activities like zinc pyrithione (ZPT) or piroctone olamine (PO). The effectiveness of these formulations has been evaluated for decades for dandruff symptom relief of volunteers. To date, non-mammalian, in vivo methods exist to test formulations of these actives. Aim. To evaluate in vivo in Galleria mellonella larva, two commercial antifungal shampoos (shampoo with 1 % ZPT and 1.6 % zinc Carbonate and shampoo with 0.5 % PO) against this species. Methodology. G. mellonella larvae were inoculated with M. globosa on abraded cuticular surface. Then, integument cell viability, histological changes, and fungal burden were evaluated. Results. Larvae inoculated with M. globosa showed higher lesion melanization and tissue damage. In addition, M. globosa population showed to increase over time. Concerning the shampoo's effectiveness, both formulations significantly reduced M. globosa burden and tissue damage. Conclusion. G. mellonella larvae were allowed to evaluate M. globosa superficial infection and antifungal effectiveness. Shampoos with ZPT and PO showed a positive effect on inoculated larvae., Competing Interests: The CeMoP research group has received funding from Procter and Gamble to finance this study. M.G.D. and J.R.S. are employees of Procter and Gamble., (Copyright © 2024 The Authors.)

Malassezia globosa is an opportunistic pathogen that causes various skin disorders, which disturbs people's life all the time, and conventional drugs are not completely satisfactory. Bacillomycin D (BD), an antifungal lipopeptide, could inhibit various fungi growth. However, the reports about its effect on M. globosa were not found yet. In this study, we showed that BD and BD-C16 (fatty acid chain had sixteen carbon atoms) completely inhibited growth of M. globosa at concentration of 64 μg/ml in 15 h, which was confirmed with the observation of irregular morphological change of M. globosa treated with BD. Significantly, the study on the working mechanism showed that BD induced cell death by changing cell membrane permeability and thus promoting the release of cellular contents, which may be mediated by the interaction between BD and ergosterol from membrane. Further study showed that BD reduced the overall content of cellular sterol, and interestingly, the expression of some genes involved in membrane and ergosterol synthesis were significantly upregulated, which was likely to be a feedback regulation. Besides, we found that BD had additive and synergistic effects with ketoconazole and amphotericin B, respectively, on inhibition of M. globosa, suggesting that combination use of BD with other commercial drugs could be a promising strategy to relieve skin disorders caused by M. globosa. Key Points: • BD could efficiently inhibit the growth of M. globosa. • BD increases cell membrane permeability and thus promotes the release of cellular contents. • BD has additive or synergistic effect with other antifungal drugs. [ABSTRACT FROM AUTHOR]

A series of monothiocarbamates (MTCs) was investigated for the inhibition of the β-class carbonic anhydrase (CAs, EC 4.2.1.1) from the fungal parasite Malassezia globosa, MgCA. These MTCs incorporate various scaffolds, among which aliphatic amine with 1–4 carbons atom in their molecule, morpholine, piperazine, as well as phenethylamine and benzylamine derivatives. All the reported MTCs displayed a better efficacy in inhibiting MgCA compared to the clinically used sulphonamide drug acetazolamide (KI of 74 μM), with KIs spanning between 1.85 and 18.9 μM. The homology model of the enzyme previously reported by us was used to rationalize the results by docking some of these MTCs within the fungal CA active site. This study might be useful to enrich the knowledge of the MgCA inhibition profile, eliciting novel ideas pertaining the design of modulators with potential efficacy in combatting dandruff or other fungal infections.

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The critical CO2 hydration reaction to bicarbonate and protons is catalyzed by carbonic anhydrases (CAs, EC 4.2.1.1). Their physiological role is to assist the transport of the CO2 and HCO3− at the cellular level, which will not be ensured by the low velocity of the uncatalyzed reaction. CA inhibition may impair the growth of microorganisms. In the yeasts, Candida albicans and Malassezia globosa, the activity of the unique β-CA identified in their genomes was demonstrated to be essential for growth of the pathogen. Here, we decided to investigate the sulfonamide inhibition profile of the homologous β-CA (MreCA) identified in the genome of Malassezia restricta, an opportunistic pathogen triggering dandruff and seborrheic dermatitis. Among 40 investigated derivatives, the best MreCA sulfonamide inhibitors were dorzolamide, brinzolamide, indisulam, valdecoxib, sulthiam, and acetazolamide (KI < 1.0 μM). The MreCA inhibition profile was different from those of the homologous enzyme from Malassezia globosa (MgCA) and the human isoenzymes (hCA I and hCA II). These results might be useful to for designing CA inhibitor scaffolds that may selectively inhibit the dandruff-producing fungi.

Summary: Dihydroxyacid dehydratase (DHAD) is a key enzyme in biosynthetic pathway of isoleucine and valine. This pathway is absent in human but exists in various organisms such as fungi. Using RNA‐seq analysis in this study, we identified MGL_3741gene which encodes DHAD protein in Malassezia globosa (M. globosa). Furthermore, we found that mentioned gene is homologous to the Ustilago maydis, Saccharomyces cerevisiae, Aspergillus flavus, and Aspergillus fumigatus ILV3P. For understanding the probable role of this gene in pathogenicity of M. globosa, we applied Real‐time PCR to investigate the differentially expressed of the MGL_3741 gene in healthy and pathogenic states. Our results indicate a significant difference between two mentioned stats. These results revealed that ILV3‐like gene in M. globosa can be related to the pathogenicity of this yeast. [ABSTRACT FROM AUTHOR]

Purpose of Review: Atopic dermatitis (AD) is a common chronic, inherited, relapsing, inflammatory skin condition. A multifactorial etiology has been postulated, including genetic and immunological factors, impaired skin barrier function and environmental triggers, all of them are relevant in the pathogenesis. Malassezia spp. is the most common fungi of the skin microbiome. Most of the studies comparing the skin colonization with Malassezia spp. in healthy people and AD patients did not show difference between both groups. This review aims to show the studies carried out in this regard and the reported evidence about the role of Malassezia spp. in the pathogenesis of AD.Recent Findings: The rate of IgE-mediated sensitization Malassezia spp. is very high in AD patients, mainly in adult patients and in patients with involvement in the head and neck. Different mechanisms have been postulated to explain the interaction of Malassezia spp. with human skin cells and immune cells and how its interaction contributes to the inflammation process in AD. Systemic and topical azole antifungals have been used with doubtful results showing beneficial effects in some AD patients.Summary: There is no clear explanation for the high frequency of Malassezia spp. sensitization in AD patients in relation with healthy individuals. Further research is necessary to determine the specific role of Malassezia in AD and the indication for the use of antifungals in this disease. [ABSTRACT FROM AUTHOR]

Carbonic anhydrases (CAs, EC 4.2.1.1) are ubiquitous metalloenzymes, which catalyze the crucial physiological CO2 hydration/dehydration reaction (CO2 + H2O ⇌ HCO3− + H+) balancing the equilibrium between CO2, H2CO3, HCO3− and CO32−. It has been demonstrated that their selective inhibition alters the equilibrium of the metabolites above affecting the biosynthesis and energy metabolism of the organism. In this context, our interest has been focalized on the fungus Malassezia restricta, which may trigger dandruff and seborrheic dermatitis altering the complex bacterial and fungal equilibrium of the human scalp. We investigated a rather large number of inorganic metal-complexing anions (a well-known class of CA inhibitors) for their interaction with the β-CA (MreCA) encoded by the M. restricta genome. The results were compared with those obtained for the two human α-CA isoforms (hCAI and hCAII) and the β-CA from Malassezia globosa. The most effective MreCA inhibitors were diethyldithiocarbamate, sulfamide, phenyl arsenic acid, stannate, tellurate, tetraborate, selenocyanate, trithiocarbonate, and bicarbonate. The different KI values obtained for the four proteins investigated might be attributed to the architectural features of their catalytic site. The anion inhibition profile is essential for better understanding the inhibition/catalytic mechanisms of these enzymes and for designing novel types of inhibitors, which may have clinical applications for the management of dandruff and seborrheic dermatitis.

Sweat is an exacerbation factor in atopic dermatitis (AD) in all age groups. A body core temperature elevation with sweating triggers cholinergic urticaria (CholU). We recently reported that AD symptoms are improved by tannic acid-containing spray, which suppresses the basophil histamine release induced by semi-purified sweat antigen in vitro , and by showering, which removes antigens in sweat from the skin surface. Sweat contains small amount of proteins including proteases, protease inhibitors, and anti-microbial peptides. We finally identified MGL_1304 secreted by Malassezia ( M. ) globosa as a major histamine – releasing antigen in human sweat. MGL_1304 is a 17-kDa protein in sweat that elicits almost the highest histamine – release activity from basophils of patients with AD and CholU among antigens derived from Malassezia species. Moreover, serum levels of anti-MGL_1304 IgE were significantly higher in patients with AD and CholU than in normal controls. The recombinant protein produced by Pichia pastoris possessed comparable allergenicity to native MGL_1304. We found a monoclonal IgE antibody against MGL_1304 which did not elicit histamine release from sensitized mast cells. Desensitization therapy using autologous sweat, or MGL_1304 purified from culture of M. globosa or its cognates might be beneficial for patients with intractable CholU due to sweat allergy. [ABSTRACT FROM AUTHOR]

A panel of 22 phenols was investigated as inhibitors of the β-class carbonic anhydrase (CAs, EC 4.2.1.1) from the fungal parasite Malassezia globosa (MgCA), a validated anti-dandruff drug target. The displayed inhibitory activities were compared to the ones previously reported against the off-target widely distributed human (h) isoforms hCA I and II. All tested phenols possessed a better efficacy in inhibiting MgCA than the clinically used sulfonamide acetazolamide, with K I s in the range of 2.5 and 65.0 μM. A homology-built model of MgCA was also used for understanding the binding mode of phenols to the fungal enzyme. Indeed, a wide network of hydrogen bonds and hydrophobic interactions between the phenol and active site residues were evidenced. The OH moiety of the inhibitor was observed anchored to the zinc-coordinated water, also making hydrogen bonds with Ser48 and Asp49. The diverse substituents at the phenolic scaffold were observed to interact with different portions of the hydrophobic pocket according to their nature and position. Considering the effective MgCA inhibitory properties of phenols, beside to the rather low inhibition against the off-target hCA I and II, this class of compounds might be of considerable interest in the cosmetics field as potential anti-dandruff drugs. [ABSTRACT FROM AUTHOR]

A series of dithiocarbamates (DTCs) was investigated for the inhibition of the β-class carbonic anhydrase (CAs, EC 4.2.1.1) from the fungal parasite Malassezia globosa , MgCA, a validated anti-dandruff drug target. These DTCs incorporate various scaffold, among which those of N,N-dimethylaminoethylenediamine, the aminoalcohols with 3–5 carbon atoms in their molecule, 3-amino-quinuclidine, piperidine, morpholine and piperazine derivatives, as well as phenethylamine and its 4-sulfamoylated derivative. Several DTCs resulted more effective in inhibiting MgCA compared to the standard sulfonamide drug acetazolamide (K I of 74 μM), with K I s ranging between 383 and 6235 nM. A computational approach, involving a homology modeling of the enzyme and docking inhibitors within its active site, helped us rationalize the results. This study may contribute to better understand the inhibition profile of MgCA, and offer new ideas for the design of modulators of activity which belong to less investigated chemical classes, thus potentially useful to combat dandruff and other fungal infections. [ABSTRACT FROM AUTHOR]

A series of monothiocarbamates (MTCs) was investigated for the inhibition of the β-class carbonic anhydrase (CAs, EC 4.2.1.1) from the fungal parasiteMalassezia globosa, MgCA. These MTCs incorporate various scaffolds, among which aliphatic amine with 1–4 carbons atom in their molecule, morpholine, piperazine, as well as phenethylamine and benzylamine derivatives. All the reported MTCs displayed a better efficacy in inhibiting MgCA compared to the clinically used sulphonamide drug acetazolamide (KIof 74 μM), with KIs spanning between 1.85 and 18.9 μM. The homology model of the enzyme previously reported by us was used to rationalize the results by docking some of these MTCs within the fungal CA active site. This study might be useful to enrich the knowledge of the MgCA inhibition profile, eliciting novel ideas pertaining the design of modulators with potential efficacy in combatting dandruff or other fungal infections. [ABSTRACT FROM PUBLISHER]

A series of N 1 -substituted aromatic sulfonamides was obtained by applying a selective sulfonamide nitration synthetic strategy leading to Ar-SO 2 NHNO 2 derivatives which were investigated as carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. Two human (h) hCA isoforms, the cytosolic hCA II and the transmembrane hCA IX, in addition to the fungal enzyme from Malassezia globosa , MgCA, were included in the study. Most of the new compounds reported selectively inhibited hCA IX over hCA II and at the same time showed effective MgCA inhibitory properties, with K I s ranging between 0.22 and 8.09 μM. The N -nitro sulfonamides are a new chemotype with CA inhibitory effects. As hCA IX was recently validated as antitumor/antimetastatic drug target, its selective inhibition could be exploited for interesting biomedical applications. Moreover, due to the effective MgCAs inhibitory properties of the N -nitro sulfonamides, of considerable interest in the cosmetics field as potential anti-dandruff agents, the N -nitro sulfonamides may be considered as interesting leads for the design of more efficient compounds targeting fungal enzymes. [ABSTRACT FROM AUTHOR]

The β-carbonic anhydrase (CA, EC 4.2.1.1) from the dandruff producing fungus Malassezia globosa , MgCA, was investigated for its activation with amines and amino acids. MgCA was weakly activated by amino acids such as l -/ d -His, l -Phe, d -DOPA, d -Trp, l -/ d -Tyr and by the amine serotonin ( K A s of 12.5–29.3 μM) but more effectively activated by d -Phe, l -DOPA, l -Trp, histamine, dopamine, pyridyl-alkylamines, and 4-(2-aminoethyl)-morpholine, with K A s of 5.82–10.9 μM. The best activators were l -adrenaline and 1-(2-aminoethyl)piperazine, with activation constants of 0.72–0.81 μM. This study may help a better understanding of the activation mechanisms of β-CAs from pathogenic fungi as well as the design of tighter binding ligands for this enzyme which is a drug target for novel types of anti-dandruff agents. [ABSTRACT FROM AUTHOR]

Background and Purpose: Species identification of Malassezia using culture-dependent methods is time-consuming due to their fastidious growth requirements. This study aimed to evaluate a rapid and accurate molecular method in order to diagnose the pityriasis versicolor (PV) and identify Malassezia species from direct clinical samples., Materials and Methods: Skin scraping or tape samples from patients with PV and healthy volunteers as the control group were collected. Diagnosis of PV was confirmed by direct microscopic examination. The DNA extraction was performed according to the steel-bullet beating method. Polymerase chain reaction-restriction fragment length polymorphism assay using Hha I restriction enzyme was applied for the identification and differentiation of Malassezia species., Results: The PCR method was able to detect Malassezia in 92.1% of specimens which were also confirmed with microscopic examination. Statistically, a significant association was observed between the results of the two assays ( P < 0.001). Moderate agreement was identified between the two methods to diagnose the PV in both populations (Kappa: 0.55). Considering microscopic examination as the gold standard method for confirmation of PV, the sensitivity, specificity, positive predictive value, and negative predictive value values of the PCR assay for recognition of PV were 85%, 75%, 92%, and 60%, respectively. M. globosa and M. restricta were the most prevalent species isolated from patients., Conclusion: In this study, the two-step molecular method based on the amplification of the D1/D2 domain and digestion of the PCR product by one restriction enzyme was able to diagnose and identify Malassezia directly from clinical samples. Consequently, it can be said that the molecular-based method provides more facilities to identify fastidious species, such as M. restricta ., Competing Interests: The authors declare no conflict of interest., (Copyright: © 2021, Published by Mazandaran University of Medical Sciences on behalf of Iranian Society of Medical Mycology and Invasive Fungi Research Center.)

MGL_1304, a major allergen in human sweat for patients with atopic dermatitis and/or cholinergic urticaria, is secreted from Malassezia globosa on human skin. The amounts of MGL_1304 and IgE against MGL_1304 are evaluated by the histamine release test using basophils or mast cells sensitized with serum containing IgE against MGL_1304, and enzyme linked sorbent assay (ELISA) using MGL_1304 and anti-MGL_1304 antibodies. Here, we identified a human monoclonal IgE (ABS-IgE) that binds to the high affinity IgE receptor (FcεRI) and MGL_1304 with high affinity (K D = 1.99 nM) but does not release histamine from basophils and mast cells. An ELISA using ABS-IgE as a standard IgE revealed that the amount of IgE against MGL_1304 (1000 U/ml) in the standard sera of patients with AD, employed in our previous report, is 32 ng/ml. A sandwich ELISA using ABS-IgE as a detection antibody showed approximately 10 times lower detection limit for MGL_1304 than ELISA in which MGL_1304 is directly bound to an ELISA plate. Moreover, ABS-IgE prevented histamine release from mast cells and basophils by neutralizing MGL_1304 not only in a free form in solution, but also on FcεRI expressed on the cell surface without cell activation. ABS-IgE may be used both to quantify the amount of MGL_1304 and anti-MGL_1304 IgE, and possibly for the treatment of diseases caused/aggravated by type I allergy to MGL_1304. [ABSTRACT FROM AUTHOR]

The genome of the fungal parasite Malassezia globosa , the causative agent of dandruff, contains a single gene annotated as encoding a carbonic anhydrase (CAs, EC 4.2.1.1) belonging to the β-class (MgCA). In an earlier work ( J. Med. Chem . 2012 , 55 , 3513) we have validated this enzyme as an anti-dandruff drug target, reporting that sulfonamide inhibitors show in vitro and in vivo effects, in an animal model of Malassezia infection. However, few classes of compounds apart the sulfonamides, were investigated for their activity against MgCA. Here we present an anion inhibition study of this enzyme, reporting that metal complexing anions such as cyanate, thiocyanate, cyanide, azide are weak MgCA inhibitors ( K I s ranging between 6.81 and 45.2 mM) whereas bicarbonate ( K I of 0.59 mM) and diethyldithiocarbamate ( K I of 0.30 mM) together with sulfamide, sulfamate, phenylboronic acid and phenylarsonic acid were the most effective inhibitors detected so far, with K I s ranging between 83 and 94 μM. This study may help a better understanding of the inhibition profile of this enzyme and may offer the possibility to design new such modulators of activity belonging to different chemical classes. [ABSTRACT FROM AUTHOR]

Malassezia globosa is pathogenic fungus that causes skin disorders including dandruff in humans. Many yeast cytochrome CYP enzymes are involved in the biosynthesis of sterols and are considered major targets of azole antifungal agents. Here, we report on the expression and characterization of the MGL_0310 gene product (CYP61A1), a sterol C-22 desaturase in M. globosa . The open reading frame of the CYP61A1 gene was amplified by PCR from M. globosa CBS 7966 genomic DNA and cloned into a pCW vector. The CYP61A1 gene was heterologously expressed in Escherichia coli and purified using a Ni 2+ -NTA affinity column. The purified CYP61A1 protein exhibited a CO-difference spectrum typical of CYPs with a maximum absorption at 452 nm. Binding spectral titration with β-sitosterol and campesterol demonstrated the type I binding mode with an increase at 411 nm and a decrease at 432 nm. The calculated K d values are 5.4 ± 0.6 μM and 6.1 ± 1.0 μM for β-sitosterol and campesterol, respectively. No metabolic product, however, was observed in the CYP61A1-supported enzyme reaction with these sterols. The purified CYP61A1 protein exhibited tight binding to azole agents, suggesting that this enzyme may be a target for the pathogenic M. globosa fungus. Moreover, several fatty acids were found to bind to CYP61A1, indicating that the architecture of the enzyme includes a relatively large active site space. This study provides new insight into the biosynthesis of fungal sterols in M. globosa and a basis for the development of antifungal as potential therapeutic agents to treat dandruff. [ABSTRACT FROM AUTHOR]

Diacylglycerol (DAG)-like lipases are found to play an important role in the life sciences and industrial fields. A putative DAG-like lipase (MgMDL2) from Malassezia globosa was cloned and expressed in recombinant Pichia pastoris. The recombinant MgMDL2 was expressed as a glycosylated protein and purified into homogeneity by anion exchange chromatography. The activity of recombinant MgMDL2 was optimal at 15 °C and pH 6.0, and it keeps over 50% of relative activity at 5 °C, suggesting that MgMDL2 was a cold active lipase. MgMDL2 retained over 80% of initial activity after incubation at 30 and 40 °C for 2.5 h, but it was not stable at 50 °C. Incubation of methanol and ethanol at a concentration of 30% for 2 h did not affect the recombinant enzyme activity, while metal ions, including Ca2+, Mn2+ and Ni2+, sharply inhibited the MgMDL2 activity at 5 mM by 42%, 35% and 36%, respectively. MgMDL2 exhibited a preference for medium chain-length esters with highest activity toward p-nitrophenyl caprylate, while it was active on mono- and diacylglycerol but not on triacylglycerol, indicating that it was a typical DAG-like lipase. By homology modeling, Phe278 was predicted to be involved in the preference of MgMDL2 for monoacyl- and diacyl-glyceride substrates, but not triglycerides. [ABSTRACT FROM AUTHOR]

Balanced skin microbiota is crucial for maintaining healthy normal skin function; however, disruption of the balance in skin microbiota is linked with skin diseases such as atopic dermatitis, acne vulgaris, dandruff, and candidiasis. Lactoplantibacillus species with proved with health benefits are probiotics that improve the balance of microbiome in skin and gut. In the present study, we investigated the potential antimicrobial activity of Lactiplantibacillus plantarum APsulloc 331261 (APsulloc 331261) and Lactiplantibacillus plantarum APsulloc 331266 (APsulloc 331266) derived from green tea, in inhibiting five skin pathogenic strains ( Staphylococcus aureus ( S. aureus ), Cutibacterium acnes ( C. acnes ), Candia albicans ( C. albicans ), Malassezia globosa ( M. globose ), and Malassezia restricta ( M. restricta )) associated with skin infection. Viability of S. aureus , C. acnes , C. albicans , M. globosa , and M. restricta was inhibited by indirect co-culture with APsulloc 331261 or APsulloc 331266 at various ratios. Different concentrations of the cell-free conditioned media (CM) derived from APsulloc 331261 or APsulloc 331266 inhibited the vaibility of S. aureus , C. acnes , C. albicans , M. globosa , and M. restricta in a dose dependent manner. Moreover, susceptibility of S. aureus , C. acnes and C. albicans against APsulloc 331261 or APsulloc 331266 was confirmed following agar overlay methods. Results of the agar overlay confirmed that various concentrations of APsulloc 331261 and APsulloc 331266 exhibited low to high inhibitory activity on the growth of S. aureus (ZDI 20.3 ± 2.1-32.3 ± 2.1 mm, R value 5.7 ± 0.8-7.8 ± 1.3 mm), C. acnes (ZDI 15.0 ± 1.7-22.2 ± 1.7 mm, R value 3.2 ± 1.3-5.5 ± 1.3 mm) and C. albicans (ZDI 13.3 ± 4.0-27.0 ± 3.6 mm, R value 2.8 ± 1.9-5.5 ± 1.7 mm). Finally, standard PCR analysis identified the presence of the of plantaricin genes encoding antimicrobial peptides in APsulloc 331261 and APsulloc 331266. These results suggest that APsulloc 331261 and APsulloc 331266 has a potential effect in the improvement of the balance of skin microbiota by inhibiting skin pathogenic strains., (© 2021 The Author(s). Published by BRI.)