Short peptides derived from EntV inhibit virulence and biofilm formation in Candida albicans

Candida albicans exists as a member of the commensal flora of the skin and gut where many complex polymicrobial interactions occur with genera such as Pseudomonas, Staphylococcus, and Streptococcus. Some of these interactions potentiate or inhibit virulence. The bacterial gastrointestinal commensal speciesEnterococcus faecalisproduces a small peptide, EntV, that modulates C. albicans virulence. The active 68 amino acid EntV peptide inhibits biofilm formationin vitro; biofilm-related infections are difficult to treat with current therapeutics. EntV also attenuates fungal virulence in a Caenorhabditis elegansinfection model and a murine oral candidiasis model. We sought to identify the regions of EntV responsible for the anti-fungal activity, and based on structural information, we hypothesized that it could be localized to a single helix of the mature peptide. In this study, we report that smaller peptides derived from this helix ranging from 12 to 16 amino acids have equal to improved efficacy in inhibiting C. albicans virulence andbiofilm formation. These smaller peptides attenuate virulence in the C. elegans infection model, inhibit initial adhesion to abiotic surfaces, and reduce the size of mature biofilms measured by confocal microscopy. Further trimming of these peptides to fewer than 11 amino acids reduces and eventually eliminates activity. These data indicate that EntV-derived peptides warrant further investigation as potential non-fungicidal additives to medical devices and antifungal therapeutics.

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Systematic characterization and genetic interaction analysis of adhesins in Candida albicans virulence

10.1101/2020.10.22.350991 ◽

2020 ◽

Author(s):

Sierra Rosiana ◽

Liyang Zhang ◽

Grace H. Kim ◽

Alexey V. Revtovich ◽

Arjun Sukumaran ◽

...

Keyword(s):

Candida Albicans ◽

Genetic Interaction ◽

Interaction Analysis ◽

Genetic Interactions ◽

Fungal Virulence ◽

C Elegans ◽

Adhesin Proteins ◽

Insight Into

AbstractCandida albicans is a microbial fungus that exists as a commensal member of the human microbiome and an opportunistic pathogen. Cell surface-associated adhesin proteins play a crucial role in C. albicans’ ability to undergo cellular morphogenesis, develop robust biofilms, colonize, and cause infection in a host. However, a comprehensive analysis of the role and relationships between these adhesins has not been explored. We previously established a CRISPR-based platform for efficient generation of single- and double-gene deletions in C. albicans, which was used to construct a library of 144 mutants, comprising 12 unique adhesin genes deleted singly, or in every possible combination of double deletions. Here, we exploit this adhesin mutant library to explore the role of adhesin proteins in C. albicans virulence. We perform a comprehensive, high-throughput screen of this library, using Caenorhabditis elegans as a simplified model host system, which identified mutants critical for virulence and significant genetic interactions. We perform follow-up analysis to assess the ability of high- and low-virulence strains to undergo cellular morphogenesis and form biofilms in vitro, as well as to colonize the C. elegans host. We further perform genetic interaction analysis to identify novel significant negative genetic interactions between adhesin mutants, whereby combinatorial perturbation of these genes significantly impairs virulence, more than expected based on virulence of the single mutant constituent strains. Together, this yields important new insight into the role of adhesins, singly and in combinations, in mediating diverse facets of virulence of this critical fungal pathogen.SummaryCandida albicans is a human fungal pathogen and cause of life-threatening systemic infections. Cell surface-associated adhesins play a central role in this pathogen’s ability to establish infection. Here, we provide a comprehensive analysis of adhesin factors, and their role in fungal virulence. Exploiting a high-throughput workflow, we screened an adhesin mutant library using C. elegans as a simple model host, and identified mutants and genetic interactions involved in virulence. We found that adhesin mutants are impaired in in vitro pathogenicity, irrespective of their virulence. Together, this work provides new insight into the role of adhesin factors in mediating fungal virulence.

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Candida albicans Hyphal Formation and Virulence Assessed Using a Caenorhabditis elegans Infection Model

Eukaryotic Cell ◽

10.1128/ec.00163-09 ◽

2009 ◽

Vol 8 (11) ◽

pp. 1750-1758 ◽

Cited By ~ 124

Author(s):

Read Pukkila-Worley ◽

Anton Y. Peleg ◽

Emmanouil Tampakakis ◽

Eleftherios Mylonakis

Keyword(s):

Candida Albicans ◽

Caenorhabditis Elegans ◽

Debaryomyces Hansenii ◽

Yeast Cells ◽

Infection Model ◽

Virulence Determinants ◽

Tissue Destruction ◽

C Elegans ◽

Hyphal Formation

ABSTRACT Candida albicans colonizes the human gastrointestinal tract and can cause life-threatening systemic infection in susceptible hosts. We study here C. albicans virulence determinants using the nematode Caenorhabditis elegans in a pathogenesis system that models candidiasis. The yeast form of C. albicans is ingested into the C. elegans digestive tract. In liquid media, the yeast cells then undergo morphological change to form hyphae, which results in aggressive tissue destruction and death of the nematode. Several lines of evidence demonstrate that hyphal formation is critical for C. albicans pathogenesis in C. elegans. First, two yeast species unable to form hyphae (Debaryomyces hansenii and Candida lusitaniae) were less virulent than C. albicans in the C. elegans assay. Second, three C. albicans mutant strains compromised in their ability to form hyphae (efg1Δ/efg1Δ, flo8Δ/flo8Δ, and cph1Δ/cph1Δ efg1Δ/efg1Δ) were dramatically attenuated for virulence. Third, the conditional tet-NRG1 strain, which enables the external manipulation of morphogenesis in vivo, was more virulent toward C. elegans when the assay was conducted under conditions that permit hyphal growth. Finally, we demonstrate the utility of the C. elegans assay in a screen for C. albicans virulence determinants, which identified several genes important for both hyphal formation in vivo and the killing of C. elegans, including the recently described CAS5 and ADA2 genes. These studies in a C. elegans-C. albicans infection model provide insights into the virulence mechanisms of an important human pathogen.

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A systemic analysis of amino acid transporters identifies Gnp2 as the main proline permease in Candida albicans

Access Microbiology ◽

10.1099/acmi.cc2021.po0080 ◽

2021 ◽

Vol 3 (12) ◽

Author(s):

Enrico Garbe ◽

Pedro Miramon ◽

Franziska Gerwien ◽

Michael Lorenz ◽

Slavena Vylkova

Keyword(s):

Amino Acids ◽

Candida Albicans ◽

Amino Acid ◽

Fungal Growth ◽

Free Form ◽

Amino Acid Transporters ◽

Acid Uptake ◽

Fungal Virulence ◽

Proline Utilization

The tight association of Candida albicans with the human host has driven the evolution of mechanisms that permit metabolic flexibility. Amino acids, present in free form or peptide bound, are an abundant carbon and nitrogen source in many host niches. Further,the capacity to sense and utilize certain amino acids, like proline, is directly linked to virulence. The C. albicans genome encodes for at least 24 amino acid permeases (AAPs), highlighting the importance of flexible amino acid uptake for fungal growth and virulence. Although the substrate specificity and role of certain AAPs has been investigated, a comprehensive characterization was missing. Therefore, we assembled a library of AAP deletion strains, which was tested for resistance to toxic amino acid analogs. Most striking was the specific resistance of gnp2Δ to the proline analog 3,4-dehydroproline. Subsequent tests validated that Gnp2 is a specific proline permease in C. albicans, which is contrary to the model yeast Saccharomyces cerevisiae where proline transport is mediated by four permeases. Furthermore, the induction of GNP2 appears to be independent of the SPS (Ssy1-Ptr3-Ssy5) regulatory pathway that controls proline utilization in the model yeast, pointing towards rewired proline uptake in C. albicans. Additionally, strains lacking GNP2were unable to respond to proline-induced filamentation, displayed decreased cytotoxicity to macrophages and showed increased sensitivity to oxidative stress, underlining the importance of proline uptake for fungal virulence. Taken together, the role of Gnp2-mediated proline uptake illustrates the importance of metabolism-driven virulence in C. albicans.

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Mucosal Bacteria Modulate Candida albicans Virulence in Oropharyngeal Candidiasis

mBio ◽

10.1128/mbio.01937-21 ◽

2021 ◽

Author(s):

M. Bertolini ◽

R. Vazquez Munoz ◽

L. Archambault ◽

S. Shah ◽

J. G. S. Souza ◽

...

Keyword(s):

Candida Albicans ◽

Carbon Source ◽

Oral Infection ◽

Infection Model ◽

Oropharyngeal Candidiasis ◽

Fungal Virulence ◽

Bacterial Composition ◽

Content Type ◽

Host Environment ◽

Bacterial Microbiome

By comparing Candida albicans virulence and the mucosal bacterial composition in a mouse oral infection model, we were able to dissect the effects of the host environment (immunosuppression), infection with C. albicans , and local modulating factors (availability of sucrose as a carbon source) on the mucosal bacterial microbiome and its role on fungal virulence. We showed that changes in endogenous microbial communities in response to sucrose can lead to attenuation of fungal disease.

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Interaction of Candida albicans with an Intestinal Pathogen, Salmonella enterica Serovar Typhimurium

Eukaryotic Cell ◽

10.1128/ec.00016-09 ◽

2009 ◽

Vol 8 (5) ◽

pp. 732-737 ◽

Cited By ~ 57

Author(s):

Emmanouil Tampakakis ◽

Anton Y. Peleg ◽

Eleftherios Mylonakis

Keyword(s):

Candida Albicans ◽

Gastrointestinal Tract ◽

Salmonella Enterica ◽

Molecular Mechanisms ◽

Bacterial Pathogen ◽

Infection Model ◽

Human Pathogens ◽

C Elegans ◽

Serovar Typhimurium

ABSTRACT Candida albicans is an opportunistic human fungal pathogen that normally resides in the gastrointestinal tract and on the skin as a commensal but can cause life-threatening invasive disease. Salmonella enterica serovar Typhimurium is a gram-negative bacterial pathogen that causes a significant amount of gastrointestinal infection in humans. Both of these organisms are also pathogenic to the nematode Caenorhabditis elegans, causing a persistent gut infection leading to worm death. In the present study, we used a previously developed C. elegans polymicrobial infection model to assess the interactions between S. Typhimurium and C. albicans. We observed that when C. elegans is infected with C. albicans and serovar Typhimurium, C. albicans filamentation is inhibited. The inhibition of C. albicans filamentation by S. Typhimurium in C. elegans appeared to be mediated by a secretary molecule, since filter-sterilized bacterial supernatant was able to inhibit C. albicans filamentation. In vitro coculture assays under planktonic conditions showed that S. Typhimurium reduces the viability of C. albicans, with greater effects seen at 37°C than at 30°C. Interestingly, S. Typhimurium reduces the viability of both yeast and filamentous forms of C. albicans, but the killing appeared more rapid for the filamentous cells. The antagonistic interaction was also observed in a C. albicans biofilm environment. This study describes the interaction between two diverse human pathogens that reside within the gastrointestinal tract and shows that the prokaryote, S. Typhimurium, reduces the viability of the eukaryote, C. albicans. Identifying the molecular mechanisms of this interaction may provide important insights into microbial pathogenesis.

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Efek Proteksi Ekstrak Etanol Stichopus hermanii Terhadap Jumlah Limfosit pada Tikus yang Terpapar Asap Rokok dan Diinduksi Candida albicans

DENTA ◽

10.30649/denta.v9i2.12 ◽

2015 ◽

Vol 9 (2) ◽

pp. 146

Author(s):

Auliasari Yunanda ◽

Syamsulina Revianti ◽

Isidora Karsini

Keyword(s):

Candida Albicans ◽

Oral Candidiasis ◽

Control Group ◽

Post Test

Latar Belakang: Merokok berhubungan dengan jamur rongga mulut yang dapat mengakibatkan oral candidiasis. Stichopus hermanii mengandung efek antioksidan, antifungi dan immunostimulator. Tujuan: Mengevaluasi efek proteksi ekstrak Stichopus hermanii terhadap jumlah limfosit pada tikus Wistar yang terpapar asap rokok dan diinduksi C.albicans. Bahan dan Metode: Rancangan penelitian ini adalah post test-only control group design. 42 ekor tikus Wistar jantan, dibagi menjadi 7 kelompok, Kelompok1 (saline 0,1mL, udara segar, CMC-Na 0,2%), Kelompok2 (saline 0,1mL, asap rokok, CMC-Na 0,2%), Kelompok3 (C.albicans 0,1mL, udara segar, CMC-Na 0,2%), Kelompok4 (C.albicans 0,1mL, asap rokok, CMC-Na 0,2%), Kelompok5 (saline 0,1mL, asap rokok, ekstrak Stichopus hermanii 0,02mg/kgBB), Kelompok6 (C.albicans 0,1mL, udara segar, ekstrak Stichopus hermanii 0,02mg/kgBB), Kelompok7 (C.albicans 0,1 mL, asap rokok, ekstrak Stichopus hermanii 0,02mg/kgBB). Tikus Wistar diinduksi C.albicans 1 minggu, terpapar asap rokok 8 minggu, dan diberi ekstrak Stichopus hermanii 8 minggu. Selanjutnya, tikus Wistar dikorbankan setelah 2 bulan perlakuan. Jumlah limfosit dihitung melalui metode hapusan darah dengan different counting dibawah mikroskop cahaya dengan pembesaran 1000x. Data yang diperoleh dianalisis menggunakan uji Kruskal-Wallis dan Mann-Whitney. Hasil: Kelompok yang terpapar asap rokok dan diinduksi C.albicans memiliki dapat menurunkan jumlah limfosit, kelompok suplementasi menggunakan ekstrak ethanol Stichopus hermanii dapat meningkatkan jumlah limfosit. Simpulan: Suplementasi ekstrak Stichopus hermanii memiliki efek protektif untuk memicu proliferasi limfosit pada tikus Wistar setelah paparan asap rokok dan induksi C.albicans.

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Antifungal Activity Directed Toward the Cell Wall by 2-Cyclohexylidenhydrazo- 4-Phenyl-Thiazole Against Candida albicans

Infectious Disorders - Drug Targets ◽

10.2174/1871526518666180531101605 ◽

2019 ◽

Vol 19 (4) ◽

pp. 428-438 ◽

Cited By ~ 1

Author(s):

Nívea P. de Sá ◽

Ana P. Pôssa ◽

Pilar Perez ◽

Jaqueline M.S. Ferreira ◽

Nayara C. Fonseca ◽

...

Keyword(s):

Cell Wall ◽

Candida Albicans ◽

Antifungal Activity ◽

Mammalian Cells ◽

C Elegans ◽

Buccal Epithelial Cells ◽

Mutant Strains ◽

Low Toxicity ◽

High Concentrations ◽

Mic Value

Background: The increasing incidence of invasive forms of candidiasis and resistance to antifungal therapy leads us to seek new and more effective antifungal compounds. Objective: To investigate the antifungal activity and toxicity as well as to evaluate the potential targets of 2- cyclohexylidenhydrazo-4-phenyl-thiazole (CPT) in Candida albicans. Methods: The antifungal activity of CPT against the survival of C. albicans was investigated in Caenorhabditis elegans. Additionally, we determined the effect of CPT on the inhibition of C. albicans adhesion capacity to buccal epithelial cells (BECs), the toxicity of CPT in mammalian cells, and the potential targets of CPT in C. albicans. Results: CPT exhibited a minimum inhibitory concentration (MIC) value of 0.4-1.9 µg/mL. Furthermore, CPT at high concentrations (>60 x MIC) showed no or low toxicity in HepG2 cells and <1% haemolysis in human erythrocytes. In addition, CPT decreased the adhesion capacity of yeasts to the BECs and prolonged the survival of C. elegans infected with C. albicans. Analysis of CPT-treated cells showed that their cell wall was thinner than that of untreated cells, especially the glucan layer. We found that there was a significantly lower quantity of 1,3-β-D-glucan present in CPT-treated cells than that in untreated cells. Assays performed on several mutant strains showed that the MIC value of CPT was high for its antifungal activity on yeasts with defective 1,3-β-glucan synthase. Conclusion: In conclusion, CPT appears to target the cell wall of C. albicans, exhibits low toxicity in mammalian cells, and prolongs the survival of C. elegans infected with C. albicans.

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Novel Aggregation Properties of Candida albicans Secreted Aspartyl Proteinase Sap6 Mediate Virulence in Oral Candidiasis

Infection and Immunity ◽

10.1128/iai.00282-15 ◽

2015 ◽

Vol 83 (7) ◽

pp. 2614-2626 ◽

Cited By ~ 35

Author(s):

Rohitashw Kumar ◽

Darpan Saraswat ◽

Swetha Tati ◽

Mira Edgerton

Keyword(s):

Candida Albicans ◽

Epithelial Cells ◽

Oral Candidiasis ◽

Oral Microbiome ◽

Proteinase Activity ◽

Adhesion Properties ◽

Content Type ◽

Oral Epithelial Cells ◽

Oral Epithelial ◽

Cell Cell

Candida albicans, a commensal fungus of the oral microbiome, causes oral candidiasis in humans with localized or systemic immune deficiencies. Secreted aspartic proteinases (Saps) are a family of 10 related proteases and are virulence factors due to their proteolytic activity, as well as their roles in adherence and colonization of host tissues. We found that mice infected sublingually withC. albicanscells overexpressing Sap6 (SAP6OE and a Δsap8strain) had thicker fungal plaques and more severe oral infection, while infection with the Δsap6strain was attenuated. These hypervirulent strains had highly aggregative colony structurein vitroand higher secreted proteinase activity; however, the levels of proteinase activity ofC. albicansSaps did not uniformly match their abilities to damage cultured oral epithelial cells (SCC-15 cells). Hyphal induction in cells overexpressing Sap6 (SAP6OE and Δsap8cells) resulted in formation of large cell-cell aggregates. These aggregates could be produced in germinated wild-type cells by addition of native or heat-inactivated Sap6. Sap6 bound only to germinated cells and increasedC. albicansadhesion to oral epithelial cells. The adhesion properties of Sap6 were lost upon deletion of its integrin-binding motif (RGD) and could be inhibited by addition of RGD peptide or anti-integrin antibodies. Thus, Sap6 (but not Sap5) has an alternative novel function in cell-cell aggregation, independent of its proteinase activity, to promote infection and virulence in oral candidiasis.

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Oral Candidiasis and COVID-19 in Users of Removable Dentures: Is Special Oral Care Needed?

Gerontology ◽

10.1159/000515214 ◽

2021 ◽

pp. 1-6

Author(s):

Laura Silva Jerônimo ◽

Rafael Paschoal Esteves Lima ◽

Thaís Yumi Umeda Suzuki ◽

José Augusto César Discacciati ◽

Cláudia Lopes Brilhante Bhering

Keyword(s):

Mechanical Ventilation ◽

Candida Albicans ◽

Oral Health ◽

Early Diagnosis ◽

Elderly Patients ◽

Oral Candidiasis ◽

Oral Care ◽

Antifungal Treatment ◽

Immunocompromised Patients ◽

Appropriate Care

Elderly patients with systemic disorders and immunocompromised patients seem to have a higher risk of developing morbidity from COVID-19. Candida albicans (C. albicans) is a potentially dangerous pathogen for these patients, especially for denture wearers with prosthetic stomatitis who require mechanical ventilation. C. albicans infection, the main candidiasis infection associated with denture wear, can complicate COVID-19 and increase the associated morbidity and mortality. Therefore, early diagnosis of C. albicans infection in COVID-19 patients is important to establish more effective antifungal treatment methods and prophylaxis strategies. Hospitalized COVID-19 patients should undergo an oral examination to assess their oral health, and those with poor oral health should receive the appropriate care and monitoring.

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Orodispersible Film Loaded with Enterococcus faecium CRL183 Presents Anti-Candida albicans Biofilm Activity In Vitro

Pharmaceutics ◽

10.3390/pharmaceutics13070998 ◽

2021 ◽

Vol 13 (7) ◽

pp. 998

Author(s):

Virgínia Barreto Lordello ◽

Andréia Bagliotti Meneguin ◽

Sarah Raquel de Annunzio ◽

Maria Pía Taranto ◽

Marlus Chorilli ◽

...

Keyword(s):

Candida Albicans ◽

Antifungal Activity ◽

Enterococcus Faecium ◽

Potato Starch ◽

Oral Candidiasis ◽

Candida Spp ◽

Sem Images ◽

Control Film ◽

In Vitro Antifungal Activity

Background: Probiotic bacteria have been emerging as a trustworthy choice for the prevention and treatment of Candida spp. infections. This study aimed to develop and characterize an orodispersible film (ODF) for delivering the potentially probiotic Enterococcus faecium CRL 183 into the oral cavity, evaluating its in vitro antifungal activity against Candida albicans. Methods and Results: The ODF was composed by carboxymethylcellulose, gelatin, and potato starch, and its physical, chemical, and mechanical properties were studied. The probiotic resistance and viability during processing and storage were evaluated as well as its in vitro antifungal activity against C. albicans. The ODFs were thin, resistant, and flexible, with neutral pH and microbiologically safe. The probiotic resisted the ODF obtaining process, demonstrating high viability (>9 log10 CFU·g−1), up to 90 days of storage at room temperature. The Probiotic Film promoted 68.9% of reduction in fungal early biofilm and 91.2% in its mature biofilm compared to the group stimulated with the control film. Those results were confirmed through SEM images. Conclusion: The probiotic ODF developed is a promising strategy to prevent oral candidiasis, since it permits the local probiotic delivery, which in turn was able to reduce C. albicans biofilm formation.

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