1
|
Ma Q, Pradhan A, Leaves I, Hickey E, Roselletti E, Dambuza I, Larcombe DE, de Assis LJ, Wilson D, Erwig LP, Netea MG, Childers DS, Brown GD, Gow NA, Brown AJ. Impact of secreted glucanases upon the cell surface and fitness of Candida albicans during colonisation and infection. Cell Surf 2024; 11:100128. [PMID: 38938582 PMCID: PMC11208952 DOI: 10.1016/j.tcsw.2024.100128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Revised: 06/01/2024] [Accepted: 06/03/2024] [Indexed: 06/29/2024] Open
Abstract
Host recognition of the pathogen-associated molecular pattern (PAMP), β-1,3-glucan, plays a major role in antifungal immunity. β-1,3-glucan is an essential component of the inner cell wall of the opportunistic pathogen Candida albicans. Most β-1,3-glucan is shielded by the outer cell wall layer of mannan fibrils, but some can become exposed at the cell surface. In response to host signals such as lactate, C. albicans shaves the exposed β-1,3-glucan from its cell surface, thereby reducing the ability of innate immune cells to recognise and kill the fungus. We have used sets of barcoded xog1 and eng1 mutants to compare the impacts of the secreted β-glucanases Xog1 and Eng1 upon C. albicans in vitro and in vivo. Flow cytometry of Fc-dectin-1-stained strains revealed that Eng1 plays the greater role in lactate-induced β-1,3-glucan masking. Transmission electron microscopy and stress assays showed that neither Eng1 nor Xog1 are essential for cell wall maintenance, but the inactivation of either enzyme compromised fungal adhesion to gut and vaginal epithelial cells. Competitive barcode sequencing suggested that neither Eng1 nor Xog1 strongly influence C. albicans fitness during systemic infection or vaginal colonisation in mice. However, the deletion of XOG1 enhanced C. albicans fitness during gut colonisation. We conclude that both Eng1 and Xog1 exert subtle effects on the C. albicans cell surface that influence fungal adhesion to host cells and that affect fungal colonisation in certain host niches.
Collapse
Affiliation(s)
- Qinxi Ma
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Arnab Pradhan
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Ian Leaves
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Emer Hickey
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Elena Roselletti
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Ivy Dambuza
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Daniel E. Larcombe
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Leandro Jose de Assis
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Duncan Wilson
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Lars P. Erwig
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Mihai G. Netea
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
- Department for Immunology & Metabolism, Life and Medical Sciences Institute (LIMES), University of Bonn, 53115 Bonn, Germany
| | - Delma S. Childers
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Gordon D. Brown
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Neil A.R. Gow
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| | - Alistair J.P. Brown
- MRC Centre for Medical Mycology, Geoffrey Pope Building, University of Exeter, Exeter EX4 4QD, UK
| |
Collapse
|
2
|
Oliveira LT, Marcos CM, Cabral AKLF, Medina-Alarcón KP, Pires RH, Fusco-Almeida AM, Mendes-Giannini MJS. Paracoccidioides spp.: the structural characterization of extracellular matrix, expression of glucan synthesis and associated genes and adhesins during biofilm formation. Front Microbiol 2024; 15:1354140. [PMID: 38516014 PMCID: PMC10955377 DOI: 10.3389/fmicb.2024.1354140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 02/19/2024] [Indexed: 03/23/2024] Open
Abstract
The genus Paracoccidioides includes Paracoccidioides lutzii and the Paracoccidioides brasiliensis complex, which comprises four phylogenetic species. A key feature distinguishing planktonic growth from biofilm is the presence of a 3D extracellular matrix (ECM). Therefore, in this study, we analyzed biofilm formation in different species of Paracoccidioides yeast phase, characterized the structural elements of the matrix of P. brasiliensis (Pb18), P. lutzii (Pl01 and 8334) and P. restrepiensis (339 and 192) and evaluated the expression of glucan genes, according to the stage of biofilm evolution for P. brasiliensis. The strains were cultivated in planktonic and biofilm form for 24-144 h. The fungi biomass and metabolic activity were determined by crystal violet and tetrazolium salt reduction (XTT) tests and colony-forming unit (CFU) by plating. The biofilm structure was designed using scanning electron microscopy and confocal laser scanning microscopy techniques. The extracellular matrix of P. brasiliensis and P. lutzii biofilms was extracted by sonication, and polysaccharides, proteins, and extracellular DNA (eDNA) were quantified. The RNA was extracted with the Trizol® reagent and quantified; then, the cDNA was synthesized to analyze the enolase expression, 14-3-3, FKS1, AGS1, GEL3, and KRE6 genes by real-time PCR. All strains of Paracoccidioides studied form a biofilm with more significant metabolic activity and biomass values in 144 h. The extracellular matrix of P. brasiliensis and P. lutzii had a higher content of polysaccharides in their composition, followed by proteins and eDNA in smaller quantities. The P. brasiliensis biofilm kinetics of formation showed greater expression of genes related to glucan's synthesis and its delivery to the external environment in addition adhesins during the biofilm's adhesion, initiation, and maturation. The GEL3 and enolase genes increased in expression within 24 h and during the biofilm maturation period, there was an increase in 14-3-3, AGS1, and FKS1. Furthermore, at 144 h, there was a decrease in KRE6 expression and an increase in GEL3. This study highlights the potential for biofilm formation for three species of Paracoccidioides and the main components of the extracellular matrix that can contribute to a better understanding of biofilm organization.
Collapse
Affiliation(s)
- Lariane Teodoro Oliveira
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, Brazil
| | - Caroline Maria Marcos
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, Brazil
| | - Ana Karla Lima Freire Cabral
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, Brazil
- Laboratory of Medical Mycology, School of Pharmaceutical Sciences, Federal University of Amazonas-UFAM, Manaus, Brazil
| | - Kaila Petronila Medina-Alarcón
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, Brazil
| | - Regina Helena Pires
- Laboratory of Mycology and Environmental Diagnosis, University of Franca, Franca, Brazil
| | - Ana Marisa Fusco-Almeida
- Department of Clinical Analysis, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, Brazil
| | | |
Collapse
|
3
|
Mourer T, d’Enfert C, Bachellier-Bassi S. Use of the Fluorescent Dye Thioflavin T to Track Amyloid Structures in the Pathogenic Yeast Candida albicans. Bio Protoc 2024; 14:e4932. [PMID: 38379825 PMCID: PMC10875357 DOI: 10.21769/bioprotoc.4932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 11/23/2023] [Accepted: 01/09/2024] [Indexed: 02/22/2024] Open
Abstract
The human pathogenic yeast Candida albicans can attach to epithelial cells or indwelling medical devices to form biofilms. These microbial communities are highly problematic in the clinic as they reduce both sensitivity to antifungal drugs and detection of fungi by the immune system. Amyloid structures are highly organized quaternary structures that play a critical role in biofilm establishment by allowing fungal cells to adhere to each other. Thus, fungal amyloids are exciting targets to develop new antifungal strategies. Thioflavin T is a specific fluorescent dye widely used to study amyloid properties of target proteins in vitro (spectrophotometry) and in vivo (epifluorescence/confocal microscopy). Notably, thioflavin T has been used to demonstrate the ability of Als5, a C. albicans adhesin, to form an amyloid fiber upon adhesion. We have developed a pipeline that allows us to study amyloid properties of target proteins using thioflavin T staining in vitro and in vivo, as well as in intact fungal biofilms. In brief, we used thioflavin T to sequentially stain (i) amyloid peptides, (ii) recombinant proteins, (iii) fungal cells treated or not with amyloid peptides, (iv) fungal amyloids enriched by cell fractionation, and (v) intact biofilms of C. albicans. Contrary to other methods, our pipeline gives a complete picture of the amyloid behavior of target proteins, from in vitro analysis to intact fungal biofilms. Using this pipeline will allow an assessment of the relevance of the in vitro results in cells and the impact of amyloids on the development and/or maintenance of fungal biofilm. Key features • Study of amyloid properties of fungal proteins. • Visualization of the subcellular localization of fungal amyloid material using epifluorescence or confocal microscopy. • Unraveling of the amyloid properties of target proteins and their physiological meaning for biofilm formation. • Observation of the presence of amyloid structures with live-cell imaging on intact fungal biofilm using confocal microscopy.
Collapse
Affiliation(s)
- Thierry Mourer
- Fungal Biology and Pathogenicity unit, Mycology Department, INRAE
USC2019, Université Paris Cité, Institut Pasteur, Paris, France
| | - Christophe d’Enfert
- Fungal Biology and Pathogenicity unit, Mycology Department, INRAE
USC2019, Université Paris Cité, Institut Pasteur, Paris, France
| | - Sophie Bachellier-Bassi
- Fungal Biology and Pathogenicity unit, Mycology Department, INRAE
USC2019, Université Paris Cité, Institut Pasteur, Paris, France
| |
Collapse
|
4
|
Lyagin I, Aslanli A, Domnin M, Stepanov N, Senko O, Maslova O, Efremenko E. Metal Nanomaterials and Hydrolytic Enzyme-Based Formulations for Improved Antifungal Activity. Int J Mol Sci 2023; 24:11359. [PMID: 37511117 PMCID: PMC10379199 DOI: 10.3390/ijms241411359] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/07/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
Active research of metal-containing compounds and enzymes as effective antifungal agents is currently being conducted due to the growing antifungal resistance problem. Metals are attracting special attention due to the wide variety of ligands that can be used for them, including chemically synthesized and naturally obtained variants as a result of the so-called "green synthesis". The main mechanism of the antifungal action of metals is the triggering of the generation and accumulation of reactive oxygen species (ROS). Further action of ROS on various biomolecules is nonspecific. Various hydrolytic enzymes (glucanases and proteases), in turn, exhibit antifungal properties by affecting the structural elements of fungal cells (cell walls, membranes), fungal quorum sensing molecules, fungal own protective agents (mycotoxins and antibiotics), and proteins responsible for the adhesion and formation of stable, highly concentrated populations in the form of biofilms. A wide substrate range of enzymes allows the use of various mechanisms of their antifungal actions. In this review, we discuss the prospects of combining two different types of antifungal agents (metals and enzymes) against mycelial fungi and yeast cells. Special attention is paid to the possible influence of metals on the activity of the enzymes and the possible effects of proteins on the antifungal activity of metal-containing compounds.
Collapse
Affiliation(s)
- Ilya Lyagin
- Faculty of Chemistry, Lomonosov Moscow State University, Lenin Hills 1/3, 119991 Moscow, Russia
| | - Aysel Aslanli
- Faculty of Chemistry, Lomonosov Moscow State University, Lenin Hills 1/3, 119991 Moscow, Russia
| | - Maksim Domnin
- Faculty of Chemistry, Lomonosov Moscow State University, Lenin Hills 1/3, 119991 Moscow, Russia
| | - Nikolay Stepanov
- Faculty of Chemistry, Lomonosov Moscow State University, Lenin Hills 1/3, 119991 Moscow, Russia
| | - Olga Senko
- Faculty of Chemistry, Lomonosov Moscow State University, Lenin Hills 1/3, 119991 Moscow, Russia
| | - Olga Maslova
- Faculty of Chemistry, Lomonosov Moscow State University, Lenin Hills 1/3, 119991 Moscow, Russia
| | - Elena Efremenko
- Faculty of Chemistry, Lomonosov Moscow State University, Lenin Hills 1/3, 119991 Moscow, Russia
| |
Collapse
|
5
|
Larcombe DE, Bohovych IM, Pradhan A, Ma Q, Hickey E, Leaves I, Cameron G, Avelar GM, de Assis LJ, Childers DS, Bain JM, Lagree K, Mitchell AP, Netea MG, Erwig LP, Gow NAR, Brown AJP. Glucose-enhanced oxidative stress resistance-A protective anticipatory response that enhances the fitness of Candida albicans during systemic infection. PLoS Pathog 2023; 19:e1011505. [PMID: 37428810 PMCID: PMC10358912 DOI: 10.1371/journal.ppat.1011505] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 07/20/2023] [Accepted: 06/22/2023] [Indexed: 07/12/2023] Open
Abstract
Most microbes have developed responses that protect them against stresses relevant to their niches. Some that inhabit reasonably predictable environments have evolved anticipatory responses that protect against impending stresses that are likely to be encountered in their niches-termed "adaptive prediction". Unlike yeasts such as Saccharomyces cerevisiae, Kluyveromyces lactis and Yarrowia lipolytica and other pathogenic Candida species we examined, the major fungal pathogen of humans, Candida albicans, activates an oxidative stress response following exposure to physiological glucose levels before an oxidative stress is even encountered. Why? Using competition assays with isogenic barcoded strains, we show that "glucose-enhanced oxidative stress resistance" phenotype enhances the fitness of C. albicans during neutrophil attack and during systemic infection in mice. This anticipatory response is dependent on glucose signalling rather than glucose metabolism. Our analysis of C. albicans signalling mutants reveals that the phenotype is not dependent on the sugar receptor repressor pathway, but is modulated by the glucose repression pathway and down-regulated by the cyclic AMP-protein kinase A pathway. Changes in catalase or glutathione levels do not correlate with the phenotype, but resistance to hydrogen peroxide is dependent on glucose-enhanced trehalose accumulation. The data suggest that the evolution of this anticipatory response has involved the recruitment of conserved signalling pathways and downstream cellular responses, and that this phenotype protects C. albicans from innate immune killing, thereby promoting the fitness of C. albicans in host niches.
Collapse
Affiliation(s)
- Daniel E. Larcombe
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Iryna M. Bohovych
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Arnab Pradhan
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Qinxi Ma
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Emer Hickey
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Ian Leaves
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Gary Cameron
- Rowett Institute, School of Medicine Medical Sciences & Nutrition, University of Aberdeen, Aberdeen, United Kingdom
| | - Gabriela M. Avelar
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Leandro J. de Assis
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Delma S. Childers
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Judith M. Bain
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Katherine Lagree
- Department of Microbiology, Biosciences Building, University of Georgia, Athens, Georgia, United States of America
| | - Aaron P. Mitchell
- Department of Microbiology, Biosciences Building, University of Georgia, Athens, Georgia, United States of America
| | - Mihai G. Netea
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, Netherlands
- Department for Immunology & Metabolism, Life and Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - Lars P. Erwig
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Johnson-Johnson Innovation, EMEA Innovation Centre, One Chapel Place, London, United Kingdom
| | - Neil A. R. Gow
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| | - Alistair J. P. Brown
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- Medical Research Council Centre for Medical Mycology, University of Exeter, School of Biosciences, Geoffrey Pope Building, Exeter, United Kingdom
| |
Collapse
|
6
|
Ma X, Liu H, Liu Z, Wang Y, Zhong Z, Peng G, Gu Y. Trichosporon asahii PLA2 Gene Enhances Drug Resistance to Azoles by Improving Drug Efflux and Biofilm Formation. Int J Mol Sci 2023; 24:ijms24108855. [PMID: 37240199 DOI: 10.3390/ijms24108855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/04/2023] [Accepted: 05/15/2023] [Indexed: 05/28/2023] Open
Abstract
Trichosporon asahii is an opportunistic pathogen that can cause severe or even fatal infections in patients with low immune function. sPLA2 plays different roles in different fungi and is also related to fungal drug resistance. However, the mechanism underlying its drug resistance to azoles has not yet been reported in T. asahii. Therefore, we investigated the drug resistance of T. asahii PLA2 (TaPLA2) by constructing overexpressing mutant strains (TaPLA2OE). TaPLA2OE was generated by homologous recombination of the recombinant vector pEGFP-N1-TaPLA2, induced by the CMV promoter, with Agrobacterium tumefaciens. The structure of the protein was found to be typical of sPLA2, and it belongs to the phospholipase A2_3 superfamily. TaPLA2OE enhanced antifungal drug resistance by upregulating the expression of effector genes and increasing the number of arthrospores to promote biofilm formation. TaPLA2OE was highly sensitive to sodium dodecyl sulfate and Congo red, indicating impaired cell wall integrity due to downregulation of chitin synthesis or degradation genes, which can indirectly affect fungal resistance. In conclusion, TaPLA2 overexpression enhanced the resistance to azoles of T. asahii by enhancing drug efflux and biofilm formation and upregulating HOG-MAPK pathway genes; therefore, it has promising research prospects.
Collapse
Affiliation(s)
- Xiaoping Ma
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Hong Liu
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Zhen Liu
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Ya Wang
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Zhijun Zhong
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Guangneng Peng
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu 611130, China
| | - Yu Gu
- College of Life Sciences, Sichuan Agricultural University, Chengdu 611130, China
| |
Collapse
|
7
|
Chauvel M, Bachellier-Bassi S, Guérout AM, Lee KK, Maufrais C, Permal E, Da Fonseca JP, Znaidi S, Mazel D, Munro CA, d'Enfert C, Legrand M. High-throughput functional profiling of the human fungal pathogen Candida albicans genome. Res Microbiol 2023; 174:104025. [PMID: 36587858 DOI: 10.1016/j.resmic.2022.104025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 12/23/2022] [Accepted: 12/26/2022] [Indexed: 12/31/2022]
Abstract
Candida albicans is a major fungal pathogen of humans. Although its genome has been sequenced more than two decades ago, there are still over 4300 uncharacterized C. albicans genes. We previously generated an ORFeome as well as a collection of destination vectors to facilitate overexpression of C. albicans ORFs. Here, we report the construction of ∼2500 overexpression mutants and their evaluation by in vitro spotting on rich medium and in a liquid pool experiment in rich medium, allowing the identification of genes whose overexpression has a fitness cost. The candidates were further validated at the individual strain level. This new resource allows large-scale screens in different growth conditions to be performed routinely. Altogether, based on the concept of identifying functionally related genes by cluster analysis, the availability of this overexpression mutant collection will facilitate the characterization of gene functions in C. albicans.
Collapse
Affiliation(s)
- Murielle Chauvel
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, F-75015 Paris, France.
| | - Sophie Bachellier-Bassi
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, F-75015 Paris, France.
| | - Anne-Marie Guérout
- Institut Pasteur, Université Paris Cité, UMR3525 CNRS, Unité Plasticité du Génome Bactérien, F-75015 Paris, France.
| | - Keunsook K Lee
- Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK; NGeneBio, 307 Daerung Post-tower 1, 288 Digital-ro, Guro-gu, Seoul 08390, Republic of Korea.
| | - Corinne Maufrais
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, F-75015 Paris, France; Institut Pasteur, Université Paris Cité, Hub de Bioinformatique, F-75015 Paris, France.
| | - Emmanuelle Permal
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, F-75015 Paris, France; Institut Pasteur, Université Paris Cité, UMR3525 CNRS, Unité Plasticité du Génome Bactérien, F-75015 Paris, France; Institut Pasteur, Université Paris Cité, Hub de Bioinformatique, F-75015 Paris, France.
| | - Juliana Pipoli Da Fonseca
- Institut Pasteur, Université Paris Cité, Plate-forme Technologique Biomics, Centre de Ressources et Recherches Technologiques (C2RT), F-75015 Paris, France.
| | - Sadri Znaidi
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, F-75015 Paris, France; Laboratoire de Microbiologie Moléculaire, Vaccinologie et Développement Biotechnologique, Institut Pasteur de Tunis, University of Tunis El Manar, Tunis-Belvédère, Tunisia.
| | - Didier Mazel
- Institut Pasteur, Université Paris Cité, UMR3525 CNRS, Unité Plasticité du Génome Bactérien, F-75015 Paris, France.
| | - Carol A Munro
- Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK.
| | - Christophe d'Enfert
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, F-75015 Paris, France.
| | - Melanie Legrand
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, F-75015 Paris, France.
| |
Collapse
|
8
|
Gervais NC, La Bella AA, Wensing LF, Sharma J, Acquaviva V, Best M, Cadena López RO, Fogal M, Uthayakumar D, Chavez A, Santiago-Tirado F, Flores-Mireles AL, Shapiro RS. Development and applications of a CRISPR activation system for facile genetic overexpression in Candida albicans. G3 (BETHESDA, MD.) 2023; 13:jkac301. [PMID: 36450451 PMCID: PMC9911074 DOI: 10.1093/g3journal/jkac301] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/02/2021] [Accepted: 11/04/2022] [Indexed: 12/02/2022]
Abstract
For the fungal pathogen Candida albicans, genetic overexpression readily occurs via a diversity of genomic alterations, such as aneuploidy and gain-of-function mutations, with important consequences for host adaptation, virulence, and evolution of antifungal drug resistance. Given the important role of overexpression on C. albicans biology, it is critical to develop and harness tools that enable the analysis of genes expressed at high levels in the fungal cell. Here, we describe the development, optimization, and application of a novel, single-plasmid-based CRISPR activation (CRISPRa) platform for targeted genetic overexpression in C. albicans, which employs a guide RNA to target an activator complex to the promoter region of a gene of interest, thus driving transcriptional expression of that gene. Using this system, we demonstrate the ability of CRISPRa to drive high levels of gene expression in C. albicans, and we assess optimal guide RNA targeting for robust and constitutive overexpression. We further demonstrate the specificity of the system via RNA sequencing. We highlight the application of CRISPR activation to overexpress genes involved in pathogenesis and drug susceptibility, and contribute toward the identification of novel phenotypes. Consequently, this tool will facilitate a broad range of applications for the study of C. albicans genetic overexpression.
Collapse
Affiliation(s)
- Nicholas C Gervais
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1H 5N4, Canada
| | - Alyssa A La Bella
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Lauren F Wensing
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1H 5N4, Canada
| | - Jehoshua Sharma
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1H 5N4, Canada
| | - Victoria Acquaviva
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1H 5N4, Canada
| | - Madison Best
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1H 5N4, Canada
| | | | - Meea Fogal
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1H 5N4, Canada
| | - Deeva Uthayakumar
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1H 5N4, Canada
- Present address: Department of Immunology, University of Toronto, Toronto, ON, Canada
| | - Alejandro Chavez
- Department of Pathology and Cell Biology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
| | | | - Ana L Flores-Mireles
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Rebecca S Shapiro
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1H 5N4, Canada
| |
Collapse
|
9
|
The Pga59 cell wall protein is an amyloid forming protein involved in adhesion and biofilm establishment in the pathogenic yeast Candida albicans. NPJ Biofilms Microbiomes 2023; 9:6. [PMID: 36697414 PMCID: PMC9877000 DOI: 10.1038/s41522-023-00371-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 01/09/2023] [Indexed: 01/26/2023] Open
Abstract
The human commensal fungus Candida albicans can attach to epithelia or indwelling medical devices and form biofilms, that are highly tolerant to antifungal drugs and can evade the immune response. The cell surface protein Pga59 has been shown to influence adhesion and biofilm formation. Here, we present evidence that Pga59 displays amyloid properties. Using electron microscopy, staining with an amyloid fibre-specific dye and X-ray diffraction experiments, we showed that the predicted amyloid-forming region of Pga59 is sufficient to build up an amyloid fibre in vitro and that recombinant Pga59 can also adopt a cross-β amyloid fibre architecture. Further, mutations impairing Pga59 amyloid assembly led to diminished adhesion to substrates and reduced biofilm production. Immunogold labelling on amyloid structures extracted from C. albicans revealed that Pga59 is used by the fungal cell to assemble amyloids within the cell wall in response to adhesion. Altogether, our results suggest that Pga59 amyloid properties are used by the fungal cell to mediate cell-substrate interactions and biofilm formation.
Collapse
|
10
|
Cattò C, Corte L, Roscini L, Cardinali G, Villa F, Cappitelli F. Metabolomic and Proteomic Changes in Candida albicans Biofilm in Response to Zosteric Acid Treatment. Int J Mol Sci 2022; 23:ijms232214067. [PMID: 36430545 PMCID: PMC9697788 DOI: 10.3390/ijms232214067] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 11/16/2022] Open
Abstract
Zosteric acid (ZA) is a secondary metabolite of the seagrass Zostera marina, with antibiofilm activity against fungi. Information concerning its mechanisms of action is lacking and this limits the development of more potent derivatives based on the same target and activity structure. The aim of this work was to investigate the ZA mode of action by analyzing the metabolic status of Candida albicans biofilm and its protein expression profile upon ZA treatment. Fourier-Transform Infrared Spectroscopy confirmed that ZA modified the metabolomic response of treated cells, showing changes in the spectral regions, mainly related to the protein compartment. Nano Liquid Chromatography-High-Resolution Mass Spectrometry highlighted that 10 proteins were differentially expressed in the C. albicans proteome upon ZA treatment. Proteins involved in the biogenesis, structure and integrity of cell walls as well as adhesion and stable attachment of hyphae were found downregulated, whereas some proteins involved in the stress response were found overexpressed. Additionally, ZA was involved in the modulation of non-DNA-based epigenetic regulatory mechanisms triggered by reactive oxygen species. These results partially clarified the ZA mechanism of action against fungi and provided insight into the major C. albicans pathways responsible for biofilm formation.
Collapse
Affiliation(s)
- Cristina Cattò
- Department of Food Environmental and Nutritional Sciences, Università degli Studi di Milano, 20133 Milano, Italy
- Correspondence: ; Tel.: +39-02-503-19121
| | - Laura Corte
- Department of Pharmaceutical Sciences-Microbiology, Università di Perugia, 06121 Perugia, Italy
| | - Luca Roscini
- Department of Pharmaceutical Sciences-Microbiology, Università di Perugia, 06121 Perugia, Italy
| | - Gianluigi Cardinali
- Department of Pharmaceutical Sciences-Microbiology, Università di Perugia, 06121 Perugia, Italy
| | - Federica Villa
- Department of Food Environmental and Nutritional Sciences, Università degli Studi di Milano, 20133 Milano, Italy
| | - Francesca Cappitelli
- Department of Food Environmental and Nutritional Sciences, Università degli Studi di Milano, 20133 Milano, Italy
| |
Collapse
|
11
|
Robbins N, Cowen LE. Genomic Approaches to Antifungal Drug Target Identification and Validation. Annu Rev Microbiol 2022; 76:369-388. [PMID: 35650665 PMCID: PMC10727914 DOI: 10.1146/annurev-micro-041020-094524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The last several decades have witnessed a surge in drug-resistant fungal infections that pose a serious threat to human health. While there is a limited arsenal of drugs that can be used to treat systemic infections, scientific advances have provided renewed optimism for the discovery of novel antifungals. The development of chemical-genomic assays using Saccharomyces cerevisiae has provided powerful methods to identify the mechanism of action of molecules in a living cell. Advances in molecular biology techniques have enabled complementary assays to be developed in fungal pathogens, including Candida albicans and Cryptococcus neoformans. These approaches enable the identification of target genes for drug candidates, as well as genes involved in buffering drug target pathways. Here, we examine yeast chemical-genomic assays and highlight how such resources can be utilized to predict the mechanisms of action of compounds, to study virulence attributes of diverse fungal pathogens, and to bolster the antifungal pipeline.
Collapse
Affiliation(s)
- Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada;
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada;
| |
Collapse
|
12
|
Transcriptomics and Phenotyping Define Genetic Signatures Associated with Echinocandin Resistance in Candida auris. mBio 2022; 13:e0079922. [PMID: 35968956 PMCID: PMC9426441 DOI: 10.1128/mbio.00799-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Candida auris emerged as a human fungal pathogen only during the past decade. Remarkably, C. auris displays high degrees of genomic diversity and phenotypic plasticity, with four major clades causing hospital outbreaks with high mortality and morbidity rates. C. auris can show clinical resistance to all classes of antifungal drugs, including echinocandins that are usually recommended as first-line therapies for invasive candidiasis. Here, we exploit transcriptomics coupled with phenotypic profiling to characterize a set of clinical C. auris isolates displaying pronounced echinocandin resistance (ECN-R). A hot spot mutation in the echinocandin FKS1 target gene is present in all resistant isolates. Moreover, ECN-R strains share a core signature set of 362 genes differentially expressed in ECN-R isolates. Among others, mitochondrial gene expression and genes affecting cell wall function appear to be the most prominent, with the latter correlating well with enhanced adhesive traits, increased cell wall mannan content, and altered sensitivity to cell wall stress of ECN-R isolates. Moreover, ECN-R phenotypic signatures were also linked to pathogen recognition and interaction with immune cells. Hence, transcriptomics paired with phenotyping is a suitable tool to predict resistance and fitness traits as well as treatment outcomes in pathogen populations with complex phenotypic diversity. IMPORTANCE The surge in antimicrobial drug resistance in some bacterial and fungal pathogens constitutes a significant challenge to health care facilities. The emerging human fungal pathogen Candida auris has been particularly concerning, as isolates can display pan-antifungal resistance traits against all drugs, including echinocandins. However, the mechanisms underlying this phenotypic diversity remain poorly understood. We identify transcriptomic signatures in C. auris isolates resistant to otherwise fungicidal echinocandins. We identify a set of differentially expressed genes shared by resistant strains compared to unrelated susceptible isolates. Moreover, phenotyping demonstrates that resistant strains show distinct behaviors, with implications for host-pathogen interactions. Hence, this work provides a solid basis to identify the mechanistic links between antifungal multidrug resistance and fitness costs that affect the interaction of C. auris with host immune defenses.
Collapse
|
13
|
van Wijlick L, Znaidi S, Hernández-Cervantes A, Basso V, Bachellier-Bassi S, d’Enfert C. Functional Portrait of Irf1 (Orf19.217), a Regulator of Morphogenesis and Iron Homeostasis in Candida albicans. Front Cell Infect Microbiol 2022; 12:960884. [PMID: 36004328 PMCID: PMC9393397 DOI: 10.3389/fcimb.2022.960884] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 07/18/2022] [Indexed: 11/17/2022] Open
Abstract
The alternate growth of Candida albicans between a unicellular yeast form and a multicellular hyphal form is crucial for its ability to cause disease. Interestingly, both morphological forms support distinct functions during proliferation in the human host. We previously identified ORF19.217 (C2_08890W_A), encoding a zinc-finger transcription factor of the C2H2 family, in a systematic screen of genes whose overexpression contributes to C. albicans' morphological changes. Conditional overexpression of ORF19.217 with the strong tetracycline-inducible promoter (P TET ) resulted in a hyperfilamentous phenotype. We examined growth of the orf19.217 knockout-mutant in different hypha-inducing conditions and found that the mutant still formed hyphae under standard hypha-inducing conditions. To further investigate the function of Orf19.217 in C. albicans, we combined genome-wide expression (RNA-Seq) and location (ChIP-Seq) analyses. We found that Orf19.217 is involved in regulatory processes comprising hyphal morphogenesis and iron acquisition. Comparative analysis with existing C. albicans hyphal transcriptomes indicates that Orf19.217-mediated filamentation is distinct from a true hyphal program. Further, the orf19.217 knockout-mutant did not show increased sensitivity to iron deprivation, but ORF19.217 overexpression was able to rescue the growth of a hap5-mutant, defective in a subunit of the CCAAT-complex, which is essential for iron acquisition. This suggested that Orf19.217 is involved in regulation of iron acquisition genes during iron deprivation and acts in a parallel pathway to the established CCAAT-complex. Interestingly, the orf19.217-mutant turned out to be defective in its ability to form filaments under iron-deficiency. Taken together our findings propose that the transcription factor Orf19.217 stimulates expression of the hyphal regulators EFG1 and BRG1 to promote filamentous growth under iron deprivation conditions, allowing the fungus to escape these iron-depleted conditions. The transcription factor therefore appears to be particularly important for adaptation of C. albicans to diverse environmental conditions in the human host. In regard to the newly identified functions, we have given the regulator the name Irf1, Iron-dependent Regulator of Filamentation.
Collapse
Affiliation(s)
- Lasse van Wijlick
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - Sadri Znaidi
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
- Institut Pasteur de Tunis, Laboratoire de Microbiologie Moléculaire, Vaccinologie et Développement Biotechnologique, Tunis-Belvédère, Tunisia
| | - Arturo Hernández-Cervantes
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - Virginia Basso
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - Sophie Bachellier-Bassi
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - Christophe d’Enfert
- Institut Pasteur, Université Paris Cité, INRAE USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
| |
Collapse
|
14
|
Oh SH, Martin-Yken H, Coleman DA, Dague E, Hoyer LL. Development and Use of a Monoclonal Antibody Specific for the Candida albicans Cell-Surface Protein Hwp1. Front Cell Infect Microbiol 2022; 12:907453. [PMID: 35832385 PMCID: PMC9273023 DOI: 10.3389/fcimb.2022.907453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/20/2022] [Indexed: 12/04/2022] Open
Abstract
The Candida albicans cell-surface protein Hwp1 functions in adhesion to the host and in biofilm formation. A peptide from the Gln-Pro-rich adhesive domain of Hwp1 was used to raise monoclonal antibody (MAb) 2-E8. MAb 2-E8 specificity for Hwp1 was demonstrated using a hwp1/hwp1 C. albicans isolate and strains that expressed at least one HWP1 allele. Immunofluorescence and atomic force microscopy experiments using MAb 2-E8 confirmed C. albicans germ-tube-specific detection of the Hwp1 protein. MAb 2-E8 also immunolabeled the tips of some Candida dubliniensis germ tubes grown under conditions that maximized HWP1 expression. The phylogeny of HWP1 and closely related genes suggested that the Gln-Pro-rich adhesive domain was unique to C. albicans and C. dubliniensis focusing the utility of MAb 2-E8 on these species. This new reagent can be used to address unanswered questions about Hwp1 and its interactions with other proteins in the context of C. albicans biology and pathogenesis.
Collapse
Affiliation(s)
- Soon-Hwan Oh
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Hélène Martin-Yken
- Toulouse Biotechnology Institute, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
- LAAS-CNRS, Université de Toulouse, CNRS, Toulouse, France
| | - David A. Coleman
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Etienne Dague
- LAAS-CNRS, Université de Toulouse, CNRS, Toulouse, France
| | - Lois L. Hoyer
- Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| |
Collapse
|
15
|
Qian W, Li X, Liu Q, Lu J, Wang T, Zhang Q. Antifungal and Antibiofilm Efficacy of Paeonol Treatment Against Biofilms Comprising Candida albicans and/or Cryptococcus neoformans. Front Cell Infect Microbiol 2022; 12:884793. [PMID: 35669114 PMCID: PMC9163411 DOI: 10.3389/fcimb.2022.884793] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 04/19/2022] [Indexed: 11/23/2022] Open
Abstract
Fungal populations are commonly found in natural environments and present enormous health care challenges, due to increased resistance to antifungal agents. Paeonol exhibits antifungal activities; nevertheless, the antifungal and antibiofilm activities of paeonol against Candida albicans and Cryptococcus neoformans remain largely unexplored. Here, we aimed to evaluate the antifungal and antibiofilm activities of paeonol against C. albicans and/or C. neoformans (i.e., against mono- or dual-species). The minimum inhibitory concentrations (MICs) of paeonol for mono-species comprising C. albicans or C. neoformans were 250 μg ml−1, whereas the MIC values of paeonol for dual-species were 500 μg ml−1. Paeonol disrupted cell membrane integrity and increased the influx of gatifloxacin into cells of mono- and dual-species cells, indicating an antifungal mode of action. Moreover, paeonol at 8 times the MIC damaged mono- and dual-species cells within C. albicans and C. neoformans biofilms, as it did planktonic cells. In particular, at 4 and 8 mg ml−1, paeonol efficiently dispersed preformed 48-h biofilms formed by mono- and dual-species cells, respectively. Paeonol inhibited effectively the yeast-to-hyphal-form transition of C. albicans and impaired capsule and melanin production of C. neoformans. The addition of 10 MIC paeonol to the medium did not shorten the lifespan of C. elegans, and 2 MIC paeonol could effectively protect the growth of C. albicans and C. neoformans-infected C. elegans. Furthermore, RNA sequencing was employed to examine the transcript profiling of C. albicans and C. neoformans biofilm cells in response to 1/2 MIC paeonol. RNA sequencing data revealed that paeonol treatment impaired biofilm formation of C. albicans by presumably downregulating the expression level of initial filamentation, adhesion, and growth-related genes, as well as biofilm biosynthesis genes, whereas paeonol inhibited biofilm formation of C. neoformans by presumably upregulating the expression level of ergosterol biosynthesis-related genes. Together, the findings of this study indicate that paeonol can be explored as a candidate antifungal agent for combating serious single and mixed infections caused by C. albicans and C. neoformans.
Collapse
Affiliation(s)
- Weidong Qian
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi’an, China
| | - Xinchen Li
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi’an, China
| | - Qiming Liu
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi’an, China
| | - Jiaxing Lu
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi’an, China
| | - Ting Wang
- School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi’an, China
- *Correspondence: Ting Wang, ; Qian Zhang,
| | - Qian Zhang
- Department of Dermatology, Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen, China
- *Correspondence: Ting Wang, ; Qian Zhang,
| |
Collapse
|
16
|
Roles of the pro-apoptotic factors CaNma111 and CaYbh3 in apoptosis and virulence of Candida albicans. Sci Rep 2022; 12:7574. [PMID: 35534671 PMCID: PMC9085738 DOI: 10.1038/s41598-022-11682-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 04/26/2022] [Indexed: 12/25/2022] Open
Abstract
Candida albicans, a commensal and opportunistic pathogen, undergoes apoptosis in response to various stimuli, including hydrogen peroxide, acetic acid, and antifungal agents. Apoptotic processes are highly conserved among mammals, plants, and fungi, but little is known about the apoptosis-regulating factors in C. albicans. In this study, C. albicans homologs of the putative apoptosis factors were identified by database screening followed by overexpression analysis. CaNma111, a homolog of the pro-apoptotic mammalian HtrA2/Omi, and CaYbh3, a homolog of BH3-only protein, yielded increased apoptotic phenotypes upon overexpression. We showed that CaNma111 and CaYbh3 functions as pro-apoptotic regulators by examining intracellular ROS accumulation, DNA end breaks (TUNEL assay), and cell survival in Canma111/Canma111 and Caybh3/Caybh3 deletion strains. We found that the protein level of CaBir1, an inhibitor-of-apoptosis (IAP) protein, was down-regulated by CaNma111. Interestingly, the Canma111/Canma111 and Caybh3/Caybh3 deletion strains showed hyperfilamentation phenotypes and increased virulence in a mouse infection model. Together, our results suggest that CaNma111 and CaYbh3 play key regulatory roles in the apoptosis and virulence of C. albicans.
Collapse
|
17
|
Kumari A, Tripathi AH, Gautam P, Gahtori R, Pande A, Singh Y, Madan T, Upadhyay SK. Adhesins in the virulence of opportunistic fungal pathogens of human. Mycology 2021; 12:296-324. [PMID: 34900383 PMCID: PMC8654403 DOI: 10.1080/21501203.2021.1934176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Aspergillosis, candidiasis, and cryptococcosis are the most common cause of mycoses-related disease and death among immune-compromised patients. Adhesins are cell-surface exposed proteins or glycoproteins of pathogens that bind to the extracellular matrix (ECM) constituents or mucosal epithelial surfaces of the host cells. The forces of interaction between fungal adhesins and host tissues are accompanied by ligand binding, hydrophobic interactions and protein-protein aggregation. Adherence is the primary and critical step involved in the pathogenesis; however, there is limited information on fungal adhesins compared to that on the bacterial adhesins. Except a few studies based on screening of proteome for adhesin identification, majority are based on characterization of individual adhesins. Recently, based on their characteristic signatures, many putative novel fungal adhesins have been predicted using bioinformatics algorithms. Some of these novel adhesin candidates have been validated by in-vitro studies; though, most of them are yet to be characterised experimentally. Morphotype specific adhesin expression as well as tissue tropism are the crucial determinants for a successful adhesion process. This review presents a comprehensive overview of various studies on fungal adhesins and discusses the targetability of the adhesins and adherence phenomenon, for combating the fungal infection in a preventive or therapeutic mode.
Collapse
Affiliation(s)
- Amrita Kumari
- Department of Biotechnology, Sir J.C. Bose Technical campus, Kumaun University, Nainital, India
| | - Ankita H Tripathi
- Department of Biotechnology, Sir J.C. Bose Technical campus, Kumaun University, Nainital, India
| | - Poonam Gautam
- ICMR-National Institute of Pathology, New Delhi, India
| | - Rekha Gahtori
- Department of Biotechnology, Sir J.C. Bose Technical campus, Kumaun University, Nainital, India
| | - Amit Pande
- Directorate of Coldwater Fisheries Research (DCFR), Nainital, India
| | - Yogendra Singh
- Department of Zoology, University of Delhi, New Delhi, India
| | - Taruna Madan
- ICMR-National Institute for Research in Reproductive Health (NIRRH), Mumbai, India
| | - Santosh K Upadhyay
- Department of Biotechnology, Sir J.C. Bose Technical campus, Kumaun University, Nainital, India
| |
Collapse
|
18
|
Dohnálek J, Dušková J, Tishchenko G, Kolenko P, Skálová T, Novák P, Fejfarová K, Šimůnek J. Chitinase Chit62J4 Essential for Chitin Processing by Human Microbiome Bacterium Clostridium paraputrificum J4. Molecules 2021; 26:molecules26195978. [PMID: 34641521 PMCID: PMC8512545 DOI: 10.3390/molecules26195978] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 09/24/2021] [Accepted: 09/27/2021] [Indexed: 12/26/2022] Open
Abstract
Commensal bacterium Clostridium paraputrificum J4 produces several extracellular chitinolytic enzymes including a 62 kDa chitinase Chit62J4 active toward 4-nitrophenyl N,N'-diacetyl-β-d-chitobioside (pNGG). We characterized the crude enzyme from bacterial culture fluid, recombinant enzyme rChit62J4, and its catalytic domain rChit62J4cat. This major chitinase, securing nutrition of the bacterium in the human intestinal tract when supplied with chitin, has a pH optimum of 5.5 and processes pNGG with Km = 0.24 mM and kcat = 30.0 s-1. Sequence comparison of the amino acid sequence of Chit62J4, determined during bacterial genome sequencing, characterizes the enzyme as a family 18 glycosyl hydrolase with a four-domain structure. The catalytic domain has the typical TIM barrel structure and the accessory domains-2x Fn3/Big3 and a carbohydrate binding module-that likely supports enzyme activity on chitin fibers. The catalytic domain is highly homologous to a single-domain chitinase of Bacillus cereus NCTU2. However, the catalytic profiles significantly differ between the two enzymes despite almost identical catalytic sites. The shift of pI and pH optimum of the commensal enzyme toward acidic values compared to the soil bacterium is the likely environmental adaptation that provides C. paraputrificum J4 a competitive advantage over other commensal bacteria.
Collapse
Affiliation(s)
- Jan Dohnálek
- Laboratory of Structure and Function of Biomolecules, Institute of Biotechnology of the Czech Academy of Sciences, v. v. i., Biocev, Průmyslová 595, 252 50 Vestec, Czech Republic; (J.D.); (P.K.); (T.S.); (K.F.)
- Correspondence: ; Tel.: +420-325-873-758; Fax: +420-325-873-710
| | - Jarmila Dušková
- Laboratory of Structure and Function of Biomolecules, Institute of Biotechnology of the Czech Academy of Sciences, v. v. i., Biocev, Průmyslová 595, 252 50 Vestec, Czech Republic; (J.D.); (P.K.); (T.S.); (K.F.)
| | - Galina Tishchenko
- Department of Structural Analysis of Biomacromolecules, Institute of Macromolecular Chemistry of the Czech Academy of Sciences, v. v. i., Heyrovsky Sq. 2, 162 06 Prague, Czech Republic;
| | - Petr Kolenko
- Laboratory of Structure and Function of Biomolecules, Institute of Biotechnology of the Czech Academy of Sciences, v. v. i., Biocev, Průmyslová 595, 252 50 Vestec, Czech Republic; (J.D.); (P.K.); (T.S.); (K.F.)
| | - Tereza Skálová
- Laboratory of Structure and Function of Biomolecules, Institute of Biotechnology of the Czech Academy of Sciences, v. v. i., Biocev, Průmyslová 595, 252 50 Vestec, Czech Republic; (J.D.); (P.K.); (T.S.); (K.F.)
| | - Petr Novák
- Laboratory of Structural Biology and Cell Signaling, Institute of Microbiology of the Czech Academy of Sciences, v. v. i., Biocev, Průmyslová 595, 252 50 Vestec, Czech Republic;
| | - Karla Fejfarová
- Laboratory of Structure and Function of Biomolecules, Institute of Biotechnology of the Czech Academy of Sciences, v. v. i., Biocev, Průmyslová 595, 252 50 Vestec, Czech Republic; (J.D.); (P.K.); (T.S.); (K.F.)
| | - Jiří Šimůnek
- Laboratory of Anaerobic Microbiology, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, v. v. i., Vídeňská 1083, 142 00 Prague, Czech Republic;
| |
Collapse
|
19
|
Rai LS, van Wijlick L, Chauvel M, d'Enfert C, Legrand M, Bachellier-Bassi S. Overexpression approaches to advance understanding of Candida albicans. Mol Microbiol 2021; 117:589-599. [PMID: 34569668 PMCID: PMC9298300 DOI: 10.1111/mmi.14818] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 09/23/2021] [Indexed: 12/15/2022]
Abstract
Candida albicans is an opportunistic fungal pathogen that is responsible for infections linked to high mortality. Loss‐of‐function approaches, taking advantage of gene knockouts or inducible down‐regulation, have been successfully used in this species in order to understand gene function. However, overexpression of a gene provides an alternative, powerful tool to elucidate gene function and identify novel phenotypes. Notably, overexpression can identify pathway components that might remain undetected using loss‐of‐function approaches. Several repressible or inducible promoters have been developed which allow to shut off or turn on the expression of a gene in C. albicans upon growth in the presence of a repressor or inducer. In this review, we summarize recent overexpression approaches used to study different aspects of C. albicans biology, including morphogenesis, biofilm formation, drug tolerance, and commensalism.
Collapse
Affiliation(s)
- Laxmi Shanker Rai
- Unité Biologie et Pathogénicité Fongiques, Institut Pasteur, Université de Paris, INRAE, USC2019, Paris, France
| | - Lasse van Wijlick
- Unité Biologie et Pathogénicité Fongiques, Institut Pasteur, Université de Paris, INRAE, USC2019, Paris, France
| | - Murielle Chauvel
- Unité Biologie et Pathogénicité Fongiques, Institut Pasteur, Université de Paris, INRAE, USC2019, Paris, France
| | - Christophe d'Enfert
- Unité Biologie et Pathogénicité Fongiques, Institut Pasteur, Université de Paris, INRAE, USC2019, Paris, France
| | - Mélanie Legrand
- Unité Biologie et Pathogénicité Fongiques, Institut Pasteur, Université de Paris, INRAE, USC2019, Paris, France
| | - Sophie Bachellier-Bassi
- Unité Biologie et Pathogénicité Fongiques, Institut Pasteur, Université de Paris, INRAE, USC2019, Paris, France
| |
Collapse
|
20
|
Li H, James A, Shen X, Wang Y. Roles of microbiota in the formation of botrytized grapes and wines. CYTA - JOURNAL OF FOOD 2021. [DOI: 10.1080/19476337.2021.1958925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Hua Li
- Beijing Advanced Innovation Center For Food Nutrition And Human Health, Beijing Technology & Business University (BTBU), Beijing, P.R. China
| | - Armachius James
- Beijing Advanced Innovation Center For Food Nutrition And Human Health, Beijing Technology & Business University (BTBU), Beijing, P.R. China
| | - Xuemei Shen
- Beijing Advanced Innovation Center For Food Nutrition And Human Health, Beijing Technology & Business University (BTBU), Beijing, P.R. China
| | - Yousheng Wang
- Beijing Advanced Innovation Center For Food Nutrition And Human Health, Beijing Technology & Business University (BTBU), Beijing, P.R. China
| |
Collapse
|
21
|
Ethylzingerone, a Novel Compound with Antifungal Activity. Antimicrob Agents Chemother 2021; 65:AAC.02711-20. [PMID: 33468481 DOI: 10.1128/aac.02711-20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 01/04/2021] [Indexed: 11/20/2022] Open
Abstract
Preservatives increase the shelf life of cosmetic products by preventing growth of contaminating microbes, including bacteria and fungi. In recent years, the Scientific Committee on Consumer Safety (SCCS) has recommended the ban or restricted use of a number of preservatives due to safety concerns. Here, we characterize the antifungal activity of ethylzingerone (hydroxyethoxyphenyl butanone [HEPB]), an SCCS-approved new preservative for use in rinse-off, oral care, and leave-on cosmetic products. We show that HEPB significantly inhibits growth of Candida albicans, Candida glabrata, and Saccharomyces cerevisiae, acting fungicidally against C. albicans Using transcript profiling experiments, we found that the C. albicans transcriptome responded to HEPB exposure by increasing the expression of genes involved in amino acid biosynthesis while activating pathways involved in chemical detoxification/oxidative stress response. Comparative analyses revealed that C. albicans phenotypic and transcriptomic responses to HEPB treatment were distinguishable from those of two widely used preservatives, triclosan and methylparaben. Chemogenomic analyses, using a barcoded S. cerevisiae nonessential mutant library, revealed that HEPB antifungal activity strongly interfered with the biosynthesis of aromatic amino acids. The trp1Δ mutants in S. cerevisiae and C. albicans were particularly sensitive to HEPB treatment, a phenotype rescued by exogenous addition of tryptophan to the growth medium, providing a direct link between HEPB mode of action and tryptophan availability. Collectively, our study sheds light on the antifungal activity of HEPB, a new molecule with safe properties for use as a preservative in the cosmetic industry, and exemplifies the powerful use of functional genomics to illuminate the mode of action of antimicrobial agents.
Collapse
|
22
|
Pál SE, Tóth R, Nosanchuk JD, Vágvölgyi C, Németh T, Gácser A. A Candida parapsilosis Overexpression Collection Reveals Genes Required for Pathogenesis. J Fungi (Basel) 2021; 7:jof7020097. [PMID: 33572958 PMCID: PMC7911391 DOI: 10.3390/jof7020097] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/18/2021] [Accepted: 01/25/2021] [Indexed: 01/07/2023] Open
Abstract
Relative to the vast data regarding the virulence mechanisms of Candida albicans, there is limited knowledge on the emerging opportunistic human pathogen Candida parapsilosis. The aim of this study was to generate and characterize an overexpression mutant collection to identify and explore virulence factors in C. parapsilosis. With the obtained mutants, we investigated stress tolerance, morphology switch, biofilm formation, phagocytosis, and in vivo virulence in Galleria mellonella larvae and mouse models. In order to evaluate the results, we compared the data from the C. parapsilosis overexpression collection analysis to the results derived from previous deletion mutant library characterizations. Of the 37 overexpression C. parapsilosis mutants, we identified eight with altered phenotypes compared to the controls. This work is the first report to identify CPAR2_107240, CPAR2_108840, CPAR2_302400, CPAR2_406400, and CPAR2_602820 as contributors to C. parapsilosis virulence by regulating functions associated with host-pathogen interactions and biofilm formation. Our findings also confirmed the role of CPAR2_109520, CPAR2_200040, and CPAR2_500180 in pathogenesis. This study was the first attempt to use an overexpression strategy to systematically assess gene function in C. parapsilosis, and our results demonstrate that this approach is effective for such investigations.
Collapse
Affiliation(s)
- Sára E. Pál
- Department of Microbiology, University of Szeged, Közép Fasor, 6726 Szeged, Hungary; (S.E.P.); (R.T.); (C.V.); (T.N.)
| | - Renáta Tóth
- Department of Microbiology, University of Szeged, Közép Fasor, 6726 Szeged, Hungary; (S.E.P.); (R.T.); (C.V.); (T.N.)
| | - Joshua D. Nosanchuk
- Departments of Medicine and Microbiology and Immunology, Albert Einstein College of Medicine, New York, NY 10461, USA;
| | - Csaba Vágvölgyi
- Department of Microbiology, University of Szeged, Közép Fasor, 6726 Szeged, Hungary; (S.E.P.); (R.T.); (C.V.); (T.N.)
| | - Tibor Németh
- Department of Microbiology, University of Szeged, Közép Fasor, 6726 Szeged, Hungary; (S.E.P.); (R.T.); (C.V.); (T.N.)
| | - Attila Gácser
- Department of Microbiology, University of Szeged, Közép Fasor, 6726 Szeged, Hungary; (S.E.P.); (R.T.); (C.V.); (T.N.)
- MTA-SZTE Lendület Mycobiome Research Group, University of Szeged, 6726 Szeged, Hungary
- Correspondence:
| |
Collapse
|
23
|
Involvement of amyloid proteins in the formation of biofilms in the pathogenic yeast Candida albicans. Res Microbiol 2021; 172:103813. [PMID: 33515679 DOI: 10.1016/j.resmic.2021.103813] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 02/07/2023]
Abstract
Candida species represent a major fungal threat for human health. Within the Candida genus, the yeast Candida albicans is the most frequently incriminated species during episodes of candidiasis or candidemia. Biofilm formation is used by C. albicans to produce a microbial community that is important in an infectious context. The cell wall, the most superficial cellular compartment, is of paramount importance regarding the establishment of biofilms. C. albicans cell wall contains proteins with amyloid properties that are necessary for biofilm formation due to their adhesion properties. This review focuses on these amyloid proteins during biofilm formation in the yeast C. albicans.
Collapse
|
24
|
Relucenti M, Familiari G, Donfrancesco O, Taurino M, Li X, Chen R, Artini M, Papa R, Selan L. Microscopy Methods for Biofilm Imaging: Focus on SEM and VP-SEM Pros and Cons. BIOLOGY 2021; 10:biology10010051. [PMID: 33445707 PMCID: PMC7828176 DOI: 10.3390/biology10010051] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 12/30/2020] [Accepted: 01/07/2021] [Indexed: 12/11/2022]
Abstract
Simple Summary Bacterial biofilms cause infections that are often resistant to antibiotic treatments. Research about the formation and elimination of biofilms cannot be undertaken without detailed imaging techniques. In this review, traditional and cutting-edge microscopy methods to study biofilm structure, ultrastructure, and 3-D architecture, with particular emphasis on conventional scanning electron microscopy and variable pressure scanning electron microscopy, are addressed, with the respective advantages and disadvantages. When ultrastructural characterization of biofilm matrix and its embedded bacterial cells is needed, as in studies on the effects of drug treatments on biofilm, scanning electron microscopy with customized protocols such as the osmium tetroxide (OsO4), ruthenium red (RR), tannic acid (TA), and ionic liquid (IL) must be preferred over other methods for the following: unparalleled image quality, magnification and resolution, minimal sample loss, and actual sample structure preservation. The first step to make a morphological assessment of the effect of the various pharmacological treatments on clinical biofilms is the production of images that faithfully reflect the structure of the sample. The extraction of quantitative parameters from images, possible using specific software, will allow for the scanning electron microscopy morphological evaluation to no longer be considered as an accessory technique, but a quantitative method to all effects. Abstract Several imaging methodologies have been used in biofilm studies, contributing to deepening the knowledge on their structure. This review illustrates the most widely used microscopy techniques in biofilm investigations, focusing on traditional and innovative scanning electron microscopy techniques such as scanning electron microscopy (SEM), variable pressure SEM (VP-SEM), environmental SEM (ESEM), and the more recent ambiental SEM (ASEM), ending with the cutting edge Cryo-SEM and focused ion beam SEM (FIB SEM), highlighting the pros and cons of several methods with particular emphasis on conventional SEM and VP-SEM. As each technique has its own advantages and disadvantages, the choice of the most appropriate method must be done carefully, based on the specific aim of the study. The evaluation of the drug effects on biofilm requires imaging methods that show the most detailed ultrastructural features of the biofilm. In this kind of research, the use of scanning electron microscopy with customized protocols such as osmium tetroxide (OsO4), ruthenium red (RR), tannic acid (TA) staining, and ionic liquid (IL) treatment is unrivalled for its image quality, magnification, resolution, minimal sample loss, and actual sample structure preservation. The combined use of innovative SEM protocols and 3-D image analysis software will allow for quantitative data from SEM images to be extracted; in this way, data from images of samples that have undergone different antibiofilm treatments can be compared.
Collapse
Affiliation(s)
- Michela Relucenti
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via Alfonso Borelli 50, 00161 Rome, Italy; (G.F.); (O.D.)
- Correspondence: ; Tel.: +39-0649918061
| | - Giuseppe Familiari
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via Alfonso Borelli 50, 00161 Rome, Italy; (G.F.); (O.D.)
| | - Orlando Donfrancesco
- Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Sapienza University of Rome, Via Alfonso Borelli 50, 00161 Rome, Italy; (G.F.); (O.D.)
| | - Maurizio Taurino
- Department of Clinical and Molecular Medicine, Unit of Vascular Surgery, Sant’Andrea Hospital, Sapienza University of Rome, Via di Grottarossa 1039, 00189 Rome, Italy;
| | - Xiaobo Li
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210096, China; (X.L.); (R.C.)
| | - Rui Chen
- Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210096, China; (X.L.); (R.C.)
| | - Marco Artini
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy; (M.A.); (R.P.); (L.S.)
| | - Rosanna Papa
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy; (M.A.); (R.P.); (L.S.)
| | - Laura Selan
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy; (M.A.); (R.P.); (L.S.)
| |
Collapse
|
25
|
de Sá NP, Pôssa AP, Perez P, Ferreira JMS, Fonseca NC, Lino CI, Cruz LB, de Oliveira RB, Rosa CA, Borelli BM, Mylonakis E, Fuchs BB, Johann S. Antifungal Activity Directed Toward the Cell Wall by 2-Cyclohexylidenhydrazo- 4-Phenyl-Thiazole Against Candida albicans. Infect Disord Drug Targets 2020; 19:428-438. [PMID: 29852876 DOI: 10.2174/1871526518666180531101605] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 05/10/2018] [Accepted: 05/28/2018] [Indexed: 12/24/2022]
Abstract
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.
Collapse
Affiliation(s)
- Nívea P de Sá
- Departamento de Microbiologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Antonio Carlos, 6627, Pampulha - CEP 31270-901, Belo Horizonte - MG, Brazil
| | - Ana P Pôssa
- Laboratorio de Microbiologia, Campus Centro- Oeste Dona Lindu, Universidade Federal de Sao Joao del-Rei, Divinópolis, Minas Gerais, Brazil
| | - Pilar Perez
- Instituto de Biologia Fundamental y Genomica CSIC, Universidad de Salamanca, Salamanca, Spain
| | - Jaqueline M S Ferreira
- Laboratorio de Microbiologia, Campus Centro- Oeste Dona Lindu, Universidade Federal de Sao Joao del-Rei, Divinópolis, Minas Gerais, Brazil
| | - Nayara C Fonseca
- Departamento de Produtos Farmaceuticos, Faculdade de Farmacia, Universidade Federal de Minas Gerais, Belo Horizonte - MG, Brazil
| | - Cleudiomar I Lino
- Departamento de Produtos Farmaceuticos, Faculdade de Farmacia, Universidade Federal de Minas Gerais, Belo Horizonte - MG, Brazil
| | - Lana B Cruz
- Departamento de Microbiologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Antonio Carlos, 6627, Pampulha - CEP 31270-901, Belo Horizonte - MG, Brazil
| | - Renata B de Oliveira
- Departamento de Produtos Farmaceuticos, Faculdade de Farmacia, Universidade Federal de Minas Gerais, Belo Horizonte - MG, Brazil
| | - Carlos A Rosa
- Departamento de Microbiologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Antonio Carlos, 6627, Pampulha - CEP 31270-901, Belo Horizonte - MG, Brazil
| | - Beatriz M Borelli
- Departamento de Microbiologia, Instituto de Ciencias Biologicas, Universidade Federal de Minas Gerais, Antonio Carlos, 6627, Pampulha - CEP 31270-901, Belo Horizonte - MG, Brazil
| | - Eleftherios Mylonakis
- Division of Infectious Diseases, Rhode Island Hospital, Alpert Medical School, and Brown University, Providence, RI, United States
| | - Beth B Fuchs
- Division of Infectious Diseases, Rhode Island Hospital, Alpert Medical School, and Brown University, Providence, RI, United States
| | - Susana Johann
- Instituto de Biologia Fundamental y Genomica CSIC, Universidad de Salamanca, Salamanca, Spain
| |
Collapse
|
26
|
Freimoser FM, Rueda-Mejia MP, Tilocca B, Migheli Q. Biocontrol yeasts: mechanisms and applications. World J Microbiol Biotechnol 2019; 35:154. [PMID: 31576429 PMCID: PMC6773674 DOI: 10.1007/s11274-019-2728-4] [Citation(s) in RCA: 121] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 09/17/2019] [Indexed: 01/10/2023]
Abstract
Yeasts occur in all environments and have been described as potent antagonists of various plant pathogens. Due to their antagonistic ability, undemanding cultivation requirements, and limited biosafety concerns, many of these unicellular fungi have been considered for biocontrol applications. Here, we review the fundamental research on the mechanisms (e.g., competition, enzyme secretion, toxin production, volatiles, mycoparasitism, induction of resistance) by which biocontrol yeasts exert their activity as plant protection agents. In a second part, we focus on five yeast species (Candida oleophila, Aureobasidium pullulans, Metschnikowia fructicola, Cryptococcus albidus, Saccharomyces cerevisiae) that are or have been registered for the application as biocontrol products. These examples demonstrate the potential of yeasts for commercial biocontrol usage, but this review also highlights the scarcity of fundamental studies on yeast biocontrol mechanisms and of registered yeast-based biocontrol products. Yeast biocontrol mechanisms thus represent a largely unexplored field of research and plentiful opportunities for the development of commercial, yeast-based applications for plant protection exist.
Collapse
Affiliation(s)
- Florian M Freimoser
- Agroscope, Research Division Plant Protection, Müller-Thurgau-Strasse 29, 8820, Wädenswil, Switzerland.
| | - Maria Paula Rueda-Mejia
- Agroscope, Research Division Plant Protection, Müller-Thurgau-Strasse 29, 8820, Wädenswil, Switzerland
| | - Bruno Tilocca
- Dipartimento di Agraria, Università degli Studi di Sassari, Viale Italia 39, 07100, Sassari, Italy
- Department of Health Sciences, University "Magna Græcia" of Catanzaro, Viale Europa, 88100, Catanzaro, Italy
| | - Quirico Migheli
- Dipartimento di Agraria, Università degli Studi di Sassari, Viale Italia 39, 07100, Sassari, Italy
- Istituto Nazionale di Biostrutture e Biosistemi and NRD - Nucleo di Ricerca sulla Desertificazione, Università degli Studi di Sassari, Viale Italia 39, 07100, Sassari, Italy
| |
Collapse
|
27
|
Denega I, d'Enfert C, Bachellier-Bassi S. Candida albicans Biofilms Are Generally Devoid of Persister Cells. Antimicrob Agents Chemother 2019; 63:e01979-18. [PMID: 30783002 PMCID: PMC6496073 DOI: 10.1128/aac.01979-18] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 02/10/2019] [Indexed: 11/20/2022] Open
Abstract
Candida albicans is known for its ability to form biofilms, which are communities of microorganisms embedded in an extracellular matrix developing on different surfaces. Biofilms are highly tolerant to antifungal therapy. This phenomenon has been partially explained by the appearance of so-called persister cells, phenotypic variants of wild-type cells, capable of surviving very high concentrations of antimicrobial agents. Persister cells in C. albicans were found exceptionally in biofilms, while none were detected in planktonic cultures of this fungus. Yet, this topic remains controversial, as others could not observe persister cells in biofilms formed by the C. albicans SC5314 laboratory strain. Due to ambiguous data in the literature, this work aimed to reevaluate the presence of persister cells in C. albicans biofilms. We demonstrated that the isolation of C. albicans "persister cells" as described previously was likely to be the result of the survival of biofilm cells that were not reached by the antifungal. We tested biofilms of SC5314 and its derivatives, as well as 95 clinical isolates, using an improved protocol, demonstrating that persister cells are not a characteristic trait of C. albicans biofilms. Although some clinical isolates are able to yield survivors upon the antifungal treatment of biofilms, this phenomenon is rather stochastic and inconsistent.
Collapse
Affiliation(s)
- Iryna Denega
- Institut Pasteur, INRA, Unité Biologie et Pathogénicité Fongiques, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Christophe d'Enfert
- Institut Pasteur, INRA, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | | |
Collapse
|
28
|
Znaidi S, van Wijlick L, Hernández‐Cervantes A, Sertour N, Desseyn J, Vincent F, Atanassova R, Gouyer V, Munro CA, Bachellier‐Bassi S, Dalle F, Jouault T, Bougnoux M, d'Enfert C. Systematic gene overexpression in Candida albicans identifies a regulator of early adaptation to the mammalian gut. Cell Microbiol 2018; 20:e12890. [PMID: 29998470 PMCID: PMC6220992 DOI: 10.1111/cmi.12890] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 06/28/2018] [Accepted: 06/28/2018] [Indexed: 12/12/2022]
Abstract
Candida albicans is part of the human gastrointestinal (GI) microbiota. To better understand how C. albicans efficiently establishes GI colonisation, we competitively challenged growth of 572 signature-tagged strains (~10% genome coverage), each conditionally overexpressing a single gene, in the murine gut. We identified CRZ2, a transcription factor whose overexpression and deletion respectively increased and decreased early GI colonisation. Using clues from genome-wide expression and gene-set enrichment analyses, we found that the optimal activity of Crz2p occurs under hypoxia at 37°C, as evidenced by both phenotypic and transcriptomic analyses following CRZ2 genetic perturbation. Consistent with early colonisation of the GI tract, we show that CRZ2 overexpression confers resistance to acidic pH and bile salts, suggesting an adaptation to the upper sections of the gut. Genome-wide location analyses revealed that Crz2p directly modulates the expression of many mannosyltransferase- and cell-wall protein-encoding genes, suggesting a link with cell-wall function. We show that CRZ2 overexpression alters cell-wall phosphomannan abundance and increases sensitivity to tunicamycin, suggesting a role in protein glycosylation. Our study reflects the powerful use of gene overexpression as a complementary approach to gene deletion to identify relevant biological pathways involved in C. albicans interaction with the host environment.
Collapse
Affiliation(s)
- Sadri Znaidi
- Institut Pasteur, INRAUnité Biologie et Pathogénicité FongiquesParisFrance
- Institut Pasteur de Tunis, University of Tunis El ManarLaboratoire de Microbiologie Moléculaire, Vaccinologie et Développement BiotechnologiqueTunisTunisia
| | - Lasse van Wijlick
- Institut Pasteur, INRAUnité Biologie et Pathogénicité FongiquesParisFrance
| | | | - Natacha Sertour
- Institut Pasteur, INRAUnité Biologie et Pathogénicité FongiquesParisFrance
| | - Jean‐Luc Desseyn
- Lille Inflammation Research International Center, UMR 995 InsermUniversité Lille 2, Faculté de MédecineLilleFrance
| | | | | | - Valérie Gouyer
- Lille Inflammation Research International Center, UMR 995 InsermUniversité Lille 2, Faculté de MédecineLilleFrance
| | - Carol A. Munro
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Institute of Medical SciencesUniversity of AberdeenAberdeenUK
| | | | - Frédéric Dalle
- UMR 1347Université de BourgogneDijonFrance
- Centre Hospitalier UniversitaireService de Parasitologie MycologieDijonFrance
| | - Thierry Jouault
- Lille Inflammation Research International Center, UMR 995 InsermUniversité Lille 2, Faculté de MédecineLilleFrance
| | - Marie‐Elisabeth Bougnoux
- Institut Pasteur, INRAUnité Biologie et Pathogénicité FongiquesParisFrance
- Laboratoire de Parasitologie‐Mycologie, Service de Microbiologie, Hôpital Necker‐Enfants MaladesUniversité Paris Descartes, Faculté de MédecineParisFrance
| | | |
Collapse
|
29
|
Legrand M, Bachellier-Bassi S, Lee KK, Chaudhari Y, Tournu H, Arbogast L, Boyer H, Chauvel M, Cabral V, Maufrais C, Nesseir A, Maslanka I, Permal E, Rossignol T, Walker LA, Zeidler U, Znaidi S, Schoeters F, Majgier C, Julien RA, Ma L, Tichit M, Bouchier C, Van Dijck P, Munro CA, d’Enfert C. Generating genomic platforms to study Candida albicans pathogenesis. Nucleic Acids Res 2018; 46:6935-6949. [PMID: 29982705 PMCID: PMC6101633 DOI: 10.1093/nar/gky594] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 06/19/2018] [Accepted: 06/25/2018] [Indexed: 12/19/2022] Open
Abstract
The advent of the genomic era has made elucidating gene function on a large scale a pressing challenge. ORFeome collections, whereby almost all ORFs of a given species are cloned and can be subsequently leveraged in multiple functional genomic approaches, represent valuable resources toward this endeavor. Here we provide novel, genome-scale tools for the study of Candida albicans, a commensal yeast that is also responsible for frequent superficial and disseminated infections in humans. We have generated an ORFeome collection composed of 5099 ORFs cloned in a Gateway™ donor vector, representing 83% of the currently annotated coding sequences of C. albicans. Sequencing data of the cloned ORFs are available in the CandidaOrfDB database at http://candidaorfeome.eu. We also engineered 49 expression vectors with a choice of promoters, tags and selection markers and demonstrated their applicability to the study of target ORFs transferred from the C. albicans ORFeome. In addition, the use of the ORFeome in the detection of protein-protein interaction was demonstrated. Mating-compatible strains as well as Gateway™-compatible two-hybrid vectors were engineered, validated and used in a proof of concept experiment. These unique and valuable resources should greatly facilitate future functional studies in C. albicans and the elucidation of mechanisms that underlie its pathogenicity.
Collapse
Affiliation(s)
- Mélanie Legrand
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
| | - Sophie Bachellier-Bassi
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
| | - Keunsook K Lee
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Yogesh Chaudhari
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Hélène Tournu
- VIB-KU Leuven Center for Microbiology, Leuven 3001, Belgium
- Laboratory of Molecular Cell Biology, KU Leuven, Leuven 3001, Belgium
| | - Laurence Arbogast
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
| | - Hélène Boyer
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
| | - Murielle Chauvel
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
| | - Vitor Cabral
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
- Univ. Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur, Paris 75015, France
| | - Corinne Maufrais
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
- Institut Pasteur-Bioinformatics and Biostatistics Hub-C3BI, USR 3756 IP CNRS-Paris 75015, France
| | - Audrey Nesseir
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
- Univ. Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur, Paris 75015, France
| | - Irena Maslanka
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Emmanuelle Permal
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
| | - Tristan Rossignol
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
| | - Louise A Walker
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Ute Zeidler
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
| | - Sadri Znaidi
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
| | - Floris Schoeters
- VIB-KU Leuven Center for Microbiology, Leuven 3001, Belgium
- Laboratory of Molecular Cell Biology, KU Leuven, Leuven 3001, Belgium
| | - Charlotte Majgier
- Modul-Bio, Parc Scientifique Luminy Biotech II, Marseille 13009, France
| | - Renaud A Julien
- Modul-Bio, Parc Scientifique Luminy Biotech II, Marseille 13009, France
| | - Laurence Ma
- Institut Pasteur-Biomics Pole-CITECH-Paris 75015, France
| | - Magali Tichit
- Institut Pasteur-Biomics Pole-CITECH-Paris 75015, France
| | | | - Patrick Van Dijck
- VIB-KU Leuven Center for Microbiology, Leuven 3001, Belgium
- Laboratory of Molecular Cell Biology, KU Leuven, Leuven 3001, Belgium
| | - Carol A Munro
- Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Christophe d’Enfert
- Fungal Biology and Pathogenicity Unit, Department of Mycology, Institut Pasteur, INRA, Paris 75015, France
| |
Collapse
|
30
|
Abstract
Candida albicans surface-attached biofilms such as those formed on intravenous catheters with direct access to the bloodstream often serve as a nidus for continuous release of cells capable of initiating new infectious foci. We previously reported that cells dispersed from a biofilm are yeast cells that originate from the top-most hyphal layers of the biofilm. Compared to their planktonic counterparts, these biofilm dispersal yeast cells displayed enhanced virulence-associated characteristics and drug resistance. However, little is known about their molecular properties. To address that issue, in this study we aimed to define the molecular characteristics of these biofilm dispersal cells. We found that the inducer of dispersal, PES1, genetically interacts with the repressor of filamentation, NRG1, in a manner consistent with the definition of dispersed cells as yeast cells. Further, using a flow biofilm model, we performed comprehensive comparative RNA sequencing on freshly dispersed cells in order to identify unique transcriptomic characteristics. Gene expression analysis demonstrated that dispersed cells largely inherit a biofilm-like mRNA profile. Strikingly, however, dispersed cells seemed transcriptionally reprogrammed to acquire nutrients such as zinc and amino acids and to metabolize alternative carbon sources, while their biofilm-associated parent cells did not induce the same high-affinity transporters or express gluconeogenetic genes, despite exposure to the same nutritional signals. Collectively, the findings from this study characterize cell dispersal as an intrinsic step of biofilm development which generates propagules more adept at colonizing distant host sites. This developmental step anticipates the need for virulence-associated gene expression before the cells experience the associated external signals. Candida albicans surface-attached biofilms serve as a reservoir of cells to perpetuate and expand an infection; cells released from biofilms on catheters have direct access to the bloodstream. Biofilm dispersal yeast cells exhibit enhanced adhesion, invasion, and biofilm formation compared to their planktonic counterparts. Here, we show using transcriptome sequencing (RNA-seq) that dispersed yeast cells are developmentally distinct from the cells in their parent biofilms as well as from planktonic yeast cells. Dispersal cells possess an anticipatory expression pattern that primes them to infect new sites in the host, to survive in nutrient-starved niches, and to invade new sites. These studies identified dispersal cells as a unique proliferative cell type of the biofilm and showed that they could serve as targets for antibiofilm drug development in the future.
Collapse
|
31
|
Lagree K, Mon HH, Mitchell AP, Ducker WA. Impact of surface topography on biofilm formation by Candida albicans. PLoS One 2018; 13:e0197925. [PMID: 29912894 PMCID: PMC6005505 DOI: 10.1371/journal.pone.0197925] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 05/10/2018] [Indexed: 11/27/2022] Open
Abstract
Candida albicans is a fungal pathogen that causes serious biofilm-based infections. Here we have asked whether surface topography may affect C. albicans biofilm formation. We tested biofilm growth of the prototypical wild-type strain SC5314 on a series of polydimethylsiloxane (PDMS) solids. The surfaces were prepared with monolayer coatings of monodisperse spherical silica particles that were fused together into a film using silica menisci. The surface topography was varied by varying the diameter of the silica particles that were used to form the film. Biofilm formation was observed to be a strong function of particle size. In the particle size range 4.0-8.0 μm, there was much more biofilm than in the size range 0.5-2.0 μm. The behavior of a clinical isolate from a clade separate from SC5314, strain p76067, showed results similar to that of SC5314. Our results suggest that topographic coatings may be a promising approach to reduce C. albicans biofilm infections.
Collapse
Affiliation(s)
- Katherine Lagree
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, United States of America
| | - Htwe H. Mon
- Department of Chemical Engineering, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, United States of America
| | - Aaron P. Mitchell
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, United States of America
| | - William A. Ducker
- Department of Chemical Engineering, and Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, United States of America
| |
Collapse
|
32
|
Lipke PN. What We Do Not Know about Fungal Cell Adhesion Molecules. J Fungi (Basel) 2018; 4:jof4020059. [PMID: 29772751 PMCID: PMC6023273 DOI: 10.3390/jof4020059] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 04/27/2018] [Accepted: 05/10/2018] [Indexed: 12/16/2022] Open
Abstract
There has been extensive research on structure and function of fungal cell adhesion molecules, but the most of the work has been about adhesins in Candida albicans and Saccharomyces cerevisiae. These yeasts are members of a single ascomycete order, and adhesion molecules from the six other fungal phyla are only sparsely described in the literature. In these other phyla, most of the research is at the cellular level, rather than at the molecular level, so there has been little characterization of the adhesion molecules themselves. A catalog of known adhesins shows some common features: high Ser/Thr content, tandem repeats, N- and O-glycosylations, GPI anchors, dibasic sequence motifs, and potential amyloid-forming sequences. However, none of these features is universal. Known ligands include proteins and glycans on homologous cells and host cells. Existing and novel tools can exploit the availability of genome sequences to identify and characterize new fungal adhesins. These include bioinformatics tools and well-established yeast surface display models, which could be coupled with an adhesion substrate array. Thus, new knowledge could be exploited to answer key questions in fungal ecology, animal and plant pathogenesis, and roles of biofilms in infection and biomass turnover.
Collapse
Affiliation(s)
- Peter N Lipke
- Biology Department, Brooklyn College, City University of New York, Brooklyn, NY 11210, USA.
- The Graduate Center, City University of New York, New York, NY 10016, USA.
| |
Collapse
|
33
|
Hall AR, Geoghegan M. Polymers and biopolymers at interfaces. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:036601. [PMID: 29368695 DOI: 10.1088/1361-6633/aa9e9c] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
This review updates recent progress in the understanding of the behaviour of polymers at surfaces and interfaces, highlighting examples in the areas of wetting, dewetting, crystallization, and 'smart' materials. Recent developments in analysis tools have yielded a large increase in the study of biological systems, and some of these will also be discussed, focussing on areas where surfaces are important. These areas include molecular binding events and protein adsorption as well as the mapping of the surfaces of cells. Important techniques commonly used for the analysis of surfaces and interfaces are discussed separately to aid the understanding of their application.
Collapse
Affiliation(s)
- A R Hall
- Department of Physics and Astronomy, University of Sheffield, Hounsfield Road, Sheffield S3 7RH, United Kingdom. Fraunhofer Project Centre for Embedded Bioanalytical Systems, Dublin City University, Glasnevin, Dublin 9, Ireland
| | | |
Collapse
|
34
|
The PHR Family: The Role of Extracellular Transglycosylases in Shaping Candida albicans Cells. J Fungi (Basel) 2017; 3:jof3040059. [PMID: 29371575 PMCID: PMC5753161 DOI: 10.3390/jof3040059] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 10/19/2017] [Accepted: 10/24/2017] [Indexed: 01/25/2023] Open
Abstract
Candida albicans is an opportunistic microorganism that can become a pathogen causing mild superficial mycosis or more severe invasive infections that can be life-threatening for debilitated patients. In the etiology of invasive infections, key factors are the adaptability of C. albicans to the different niches of the human body and the transition from a yeast form to hypha. Hyphal morphology confers high adhesiveness to the host cells, as well as the ability to penetrate into organs. The cell wall plays a crucial role in the morphological changes C. albicans undergoes in response to specific environmental cues. Among the different categories of enzymes involved in the formation of the fungal cell wall, the GH72 family of transglycosylases plays an important assembly role. These enzymes cut and religate β-(1,3)-glucan, the major determinant of cell shape. In C. albicans, the PHR family encodes GH72 enzymes, some of which work in specific environmental conditions. In this review, we will summarize the work from the initial discovery of PHR genes to the study of the pH-dependent expression of PHR1 and PHR2, from the characterization of the gene products to the recent findings concerning the stress response generated by the lack of GH72 activity in C. albicans hyphae.
Collapse
|
35
|
Abstract
We focus this article on turning a biofilm inside out. The "inside" of the biofilm comprises the individual biofilm-related phenotypes, their environmental drivers and genetic determinants, and the coordination of gene functions through transcriptional regulators. Investigators have viewed the inside of the biofilm through diverse approaches, and this article will attempt to capture the essence of many. The ultimate goal is to connect the inside to the "outside," which we view as biofilm structure, development, pharmacological attributes, and medical impact.
Collapse
|
36
|
Pradhan A, Herrero-de-Dios C, Belmonte R, Budge S, Lopez Garcia A, Kolmogorova A, Lee KK, Martin BD, Ribeiro A, Bebes A, Yuecel R, Gow NAR, Munro CA, MacCallum DM, Quinn J, Brown AJP. Elevated catalase expression in a fungal pathogen is a double-edged sword of iron. PLoS Pathog 2017; 13:e1006405. [PMID: 28542620 PMCID: PMC5456399 DOI: 10.1371/journal.ppat.1006405] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 06/02/2017] [Accepted: 05/09/2017] [Indexed: 11/18/2022] Open
Abstract
Most fungal pathogens of humans display robust protective oxidative stress responses that contribute to their pathogenicity. The induction of enzymes that detoxify reactive oxygen species (ROS) is an essential component of these responses. We showed previously that ectopic expression of the heme-containing catalase enzyme in Candida albicans enhances resistance to oxidative stress, combinatorial oxidative plus cationic stress, and phagocytic killing. Clearly ectopic catalase expression confers fitness advantages in the presence of stress, and therefore in this study we tested whether it enhances fitness in the absence of stress. We addressed this using a set of congenic barcoded C. albicans strains that include doxycycline-conditional tetON-CAT1 expressors. We show that high basal catalase levels, rather than CAT1 induction following stress imposition, reduce ROS accumulation and cell death, thereby promoting resistance to acute peroxide or combinatorial stress. This conclusion is reinforced by our analyses of phenotypically diverse clinical isolates and the impact of stochastic variation in catalase expression upon stress resistance in genetically homogeneous C. albicans populations. Accordingly, cat1Δ cells are more sensitive to neutrophil killing. However, we find that catalase inactivation does not attenuate C. albicans virulence in mouse or invertebrate models of systemic candidiasis. Furthermore, our direct comparisons of fitness in vitro using isogenic barcoded CAT1, cat1Δ and tetON-CAT1 strains show that, while ectopic catalase expression confers a fitness advantage during peroxide stress, it confers a fitness defect in the absence of stress. This fitness defect is suppressed by iron supplementation. Also high basal catalase levels induce key iron assimilatory functions (CFL5, FET3, FRP1, FTR1). We conclude that while high basal catalase levels enhance peroxide stress resistance, they place pressure on iron homeostasis through an elevated cellular demand for iron, thereby reducing the fitness of C. albicans in iron-limiting tissues within the host. The pathogenic yeast Candida albicans faces multiple challenges within its human host. These include the need to protect itself against the toxic oxidants used by the host to kill invading microbes, and the need to scavenge iron, an essential micronutrient that is limiting in certain tissues. The iron-containing enzyme, catalase, detoxifies hydrogen peroxide, thereby playing a major role in protecting C. albicans against reactive oxygen species and neutrophil killing. Indeed, we show that high basal catalase expression increases the resistance of this yeast to oxidative and combinatorial (oxidative plus cationic) stresses. Yet, rather than enhancing the virulence of C. albicans as had been predicted, high basal catalase expression decreases fungal colonisation in certain iron-limiting tissues. Furthermore, we demonstrate that catalase inactivation does not significantly perturb the virulence of C. albicans in models of systemic infection. We also show that ectopic catalase expression increases the demand for iron in C. albicans, thereby reducing the fitness of this pathogen in the absence of stress under iron-limiting conditions. Therefore, high basal catalase expression is a double-edged sword: it enhances the fitness of C. albicans in the presence of stress, but reduces fitness in the absence of stress. This explains why catalase overexpression reduces rather than enhances virulence.
Collapse
Affiliation(s)
- Arnab Pradhan
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Carmen Herrero-de-Dios
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Rodrigo Belmonte
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Susan Budge
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Angela Lopez Garcia
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Aljona Kolmogorova
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Keunsook K. Lee
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Brennan D. Martin
- Centre for Genome-Enabled Biology and Medicine, University of Aberdeen, Aberdeen, United Kingdom
| | - Antonio Ribeiro
- Centre for Genome-Enabled Biology and Medicine, University of Aberdeen, Aberdeen, United Kingdom
| | - Attila Bebes
- Iain Fraser Cytometry Centre, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Raif Yuecel
- Iain Fraser Cytometry Centre, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Neil A. R. Gow
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Carol A. Munro
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Donna M. MacCallum
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
| | - Janet Quinn
- Institute for Cell and Molecular Biosciences, University of Newcastle, Newcastle upon Tyne, United Kingdom
| | - Alistair J. P. Brown
- Aberdeen Fungal Group, MRC Centre for Medical Mycology, University of Aberdeen, Institute of Medical Sciences, Aberdeen, United Kingdom
- * E-mail:
| |
Collapse
|
37
|
Abstract
We focus this article on turning a biofilm inside out. The "inside" of the biofilm comprises the individual biofilm-related phenotypes, their environmental drivers and genetic determinants, and the coordination of gene functions through transcriptional regulators. Investigators have viewed the inside of the biofilm through diverse approaches, and this article will attempt to capture the essence of many. The ultimate goal is to connect the inside to the "outside," which we view as biofilm structure, development, pharmacological attributes, and medical impact.
Collapse
Affiliation(s)
- Katherine Lagree
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Aaron P Mitchell
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213
| |
Collapse
|
38
|
Functional Genomic Analysis of Candida albicans Adherence Reveals a Key Role for the Arp2/3 Complex in Cell Wall Remodelling and Biofilm Formation. PLoS Genet 2016; 12:e1006452. [PMID: 27870871 PMCID: PMC5147769 DOI: 10.1371/journal.pgen.1006452] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 10/31/2016] [Indexed: 12/28/2022] Open
Abstract
Fungal biofilms are complex, structured communities that can form on surfaces such as catheters and other indwelling medical devices. Biofilms are of particular concern with Candida albicans, one of the leading opportunistic fungal pathogens of humans. C. albicans biofilms include yeast and filamentous cells that are surrounded by an extracellular matrix, and they are intrinsically resistant to antifungal drugs such that resolving biofilm infections often requires surgery to remove the contaminated device. C. albicans biofilms form through a regulated process of adhesion to surfaces, filamentation, maturation, and ultimately dispersion. To uncover new strategies to block the initial stages of biofilm formation, we utilized a functional genomic approach to identify genes that modulate C. albicans adherence. We screened a library of 1,481 double barcoded doxycycline-repressible conditional gene expression strains covering ~25% of the C. albicans genome. We identified five genes for which transcriptional repression impaired adherence, including: ARC18, PMT1, MNN9, SPT7, and orf19.831. The most severe adherence defect was observed upon transcriptional repression of ARC18, which encodes a member of the Arp2/3 complex that is involved in regulation of the actin cytoskeleton and endocytosis. Depletion of components of the Arp2/3 complex not only impaired adherence, but also caused reduced biofilm formation, increased cell surface hydrophobicity, and increased exposure of cell wall chitin and β-glucans. Reduced function of the Arp2/3 complex led to impaired cell wall integrity and activation of Rho1-mediated cell wall stress responses, thereby causing cell wall remodelling and reduced adherence. Thus, we identify important functional relationships between cell wall stress responses and a novel mechanism that controls adherence and biofilm formation, thereby illuminating novel strategies to cripple a leading fungal pathogen of humans.
Collapse
|
39
|
Azeredo J, Azevedo NF, Briandet R, Cerca N, Coenye T, Costa AR, Desvaux M, Di Bonaventura G, Hébraud M, Jaglic Z, Kačániová M, Knøchel S, Lourenço A, Mergulhão F, Meyer RL, Nychas G, Simões M, Tresse O, Sternberg C. Critical review on biofilm methods. Crit Rev Microbiol 2016; 43:313-351. [PMID: 27868469 DOI: 10.1080/1040841x.2016.1208146] [Citation(s) in RCA: 541] [Impact Index Per Article: 67.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Biofilms are widespread in nature and constitute an important strategy implemented by microorganisms to survive in sometimes harsh environmental conditions. They can be beneficial or have a negative impact particularly when formed in industrial settings or on medical devices. As such, research into the formation and elimination of biofilms is important for many disciplines. Several new methodologies have been recently developed for, or adapted to, biofilm studies that have contributed to deeper knowledge on biofilm physiology, structure and composition. In this review, traditional and cutting-edge methods to study biofilm biomass, viability, structure, composition and physiology are addressed. Moreover, as there is a lack of consensus among the diversity of techniques used to grow and study biofilms. This review intends to remedy this, by giving a critical perspective, highlighting the advantages and limitations of several methods. Accordingly, this review aims at helping scientists in finding the most appropriate and up-to-date methods to study their biofilms.
Collapse
Affiliation(s)
- Joana Azeredo
- a CEB ? Centre of Biological Engineering, LIBRO, Laboratórios de Biofilmes Rosário Oliveira, University of Minho Campus de Gualtar , Braga , Portugal
| | - Nuno F Azevedo
- b LEPABE, Department of Chemical Engineering, Faculty of Engineering , University of Porto , Porto , Portugal
| | - Romain Briandet
- c Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay , Jouy-en-Josas , France
| | - Nuno Cerca
- a CEB ? Centre of Biological Engineering, LIBRO, Laboratórios de Biofilmes Rosário Oliveira, University of Minho Campus de Gualtar , Braga , Portugal
| | - Tom Coenye
- d Laboratory of Pharmaceutical Microbiology , Ghent University , Ghent , Belgium
| | - Ana Rita Costa
- a CEB ? Centre of Biological Engineering, LIBRO, Laboratórios de Biofilmes Rosário Oliveira, University of Minho Campus de Gualtar , Braga , Portugal
| | - Mickaël Desvaux
- e INRA Centre Auvergne-Rhône-Alpes , UR454 Microbiologie , Saint-Genès Champanelle , France
| | - Giovanni Di Bonaventura
- f Department of Medical, Oral, and Biotechnological Sciences, and Center of Excellence on Aging and Translational Medicine (CeSI-MeT) , "G. d'Annunzio" University of Chieti-Pescara , Chieti , Italy
| | - Michel Hébraud
- e INRA Centre Auvergne-Rhône-Alpes , UR454 Microbiologie , Saint-Genès Champanelle , France
| | - Zoran Jaglic
- g Department of Food and Feed Safety, Laboratory of Food Bacteriology , Veterinary Research Institute , Brno , Czech Republic
| | - Miroslava Kačániová
- h Department of Microbiology, Faculty of Biotechnology and Food Sciences , Slovak University of Agriculture in Nitra , Nitra , Slovakia
| | - Susanne Knøchel
- i Department of Food Science (FOOD) , University of Copenhagen , Frederiksberg C , Denmark
| | - Anália Lourenço
- j Department of Computer Science , University of Vigo , Ourense , Spain
| | - Filipe Mergulhão
- b LEPABE, Department of Chemical Engineering, Faculty of Engineering , University of Porto , Porto , Portugal
| | - Rikke Louise Meyer
- k Aarhus University, Interdisciplinary Nanoscience Center (iNANO) , Aarhus , Denmark
| | - George Nychas
- l Agricultural University of Athens, Lab of Microbiology and Biotechnology of Foods , Athens , Greece
| | - Manuel Simões
- b LEPABE, Department of Chemical Engineering, Faculty of Engineering , University of Porto , Porto , Portugal
| | - Odile Tresse
- m LUNAM Université, Oniris, SECALIM UMR1024 INRA , Université de Nantes , Nantes , France
| | - Claus Sternberg
- n Department of Biotechnology and Biomedicine , Technical University of Denmark , Lyngby, Denmark
| |
Collapse
|
40
|
Mechanisms Underlying the Delayed Activation of the Cap1 Transcription Factor in Candida albicans following Combinatorial Oxidative and Cationic Stress Important for Phagocytic Potency. mBio 2016; 7:e00331. [PMID: 27025253 PMCID: PMC4817257 DOI: 10.1128/mbio.00331-16] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Following phagocytosis, microbes are exposed to an array of antimicrobial weapons that include reactive oxygen species (ROS) and cationic fluxes. This is significant as combinations of oxidative and cationic stresses are much more potent than the corresponding single stresses, triggering the synergistic killing of the fungal pathogen Candida albicans by “stress pathway interference.” Previously we demonstrated that combinatorial oxidative plus cationic stress triggers a dramatic increase in intracellular ROS levels compared to oxidative stress alone. Here we show that activation of Cap1, the major regulator of antioxidant gene expression in C. albicans, is significantly delayed in response to combinatorial stress treatments and to high levels of H2O2. Cap1 is normally oxidized in response to H2O2; this masks the nuclear export sequence, resulting in the rapid nuclear accumulation of Cap1 and the induction of Cap1-dependent genes. Here we demonstrate that following exposure of cells to combinatorial stress or to high levels of H2O2, Cap1 becomes trapped in a partially oxidized form, Cap1OX-1. Notably, Cap1-dependent gene expression is not induced when Cap1 is in this partially oxidized form. However, while Cap1OX-1 readily accumulates in the nucleus and binds to target genes following high-H2O2 stress, the nuclear accumulation of Cap1OX-1 following combinatorial H2O2 and NaCl stress is delayed due to a cationic stress-enhanced interaction with the Crm1 nuclear export factor. These findings define novel mechanisms that delay activation of the Cap1 transcription factor, thus preventing the rapid activation of the stress responses vital for the survival of C. albicans within the host. Combinatorial stress-mediated synergistic killing represents a new unchartered area in the field of stress signaling. This phenomenon contrasts starkly with “stress cross-protection,” where exposure to one stress protects against subsequent exposure to a different stress. Previously we demonstrated that the pathogen Candida albicans is acutely sensitive to combinations of cationic and oxidative stresses, because the induction of H2O2-responsive genes is blocked in the presence of cationic stress. We reveal that this is due to novel mechanisms that delay activation of the Cap1 AP-1-like transcription factor, the major regulator of the H2O2-induced regulon. Cap1 becomes trapped in a partially oxidized form following simultaneous exposure to oxidative and cationic stresses. In addition, cationic stress promotes the interaction of Cap1 with the Crm1 nuclear export factor, thus inhibiting its nuclear accumulation. These mechanisms probably explain the potency of neutrophils, which employ multiple stresses to kill fungal pathogens.
Collapse
|
41
|
Böhm L, Muralidhara P, Pérez JC. ACandida albicansregulator of disseminated infection operates primarily as a repressor and governs cell surface remodeling. Mol Microbiol 2016; 100:328-44. [DOI: 10.1111/mmi.13320] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/21/2015] [Indexed: 11/26/2022]
Affiliation(s)
- Lena Böhm
- Interdisciplinary Center for Clinical Research, University Hospital Würzburg; Würzburg Germany
- Institute for Molecular Infection Biology, University of Würzburg; Würzburg Germany
| | | | - J. Christian Pérez
- Interdisciplinary Center for Clinical Research, University Hospital Würzburg; Würzburg Germany
- Institute for Molecular Infection Biology, University of Würzburg; Würzburg Germany
| |
Collapse
|
42
|
d'Enfert C, Janbon G. Biofilm formation in Candida glabrata: What have we learnt from functional genomics approaches? FEMS Yeast Res 2015; 16:fov111. [PMID: 26678748 DOI: 10.1093/femsyr/fov111] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/14/2015] [Indexed: 12/13/2022] Open
Abstract
Biofilms are a source of therapeutic failures because of their intrinsic tolerance to antimicrobials. Candida glabrata is one of the pathogenic yeasts that is responsible for life-threatening disseminated infections and able to form biofilms on medical devices such as vascular and urinary catheters. Recent progresses in the functional genomics of C. glabrata have been applied to the study of biofilm formation, revealing the contribution of an array of genes to this process. In particular, the Yak1 kinase and the Swi/Snf chromatin remodeling complex have been shown to relieve the repression exerted by subtelomeric silencing on the expression of the EPA6 and EPA7 genes, thus allowing the encoded adhesins to exert their key roles in biofilm formation. This provides a framework to evaluate the contribution of other genes that have been genetically linked to biofilm development and, based on the function of their orthologs in Saccharomyces cerevisiae, appear to have roles in adaptation to nutrient deprivation, calcium signaling, cell wall remodeling and adherence. Future studies combining the use of in vitro and animal models of biofilm formation, omics approaches and forward or reverse genetics are needed to expand the current knowledge of C. glabrata biofilm formation and reveal the mechanisms underlying their antifungal tolerance.
Collapse
Affiliation(s)
- Christophe d'Enfert
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Mycologie, F-75015 Paris, France INRA, USC2019, F-75015 Paris, France
| | - Guilhem Janbon
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Mycologie, F-75015 Paris, France INRA, USC2019, F-75015 Paris, France
| |
Collapse
|
43
|
Borghi E, Morace G, Borgo F, Rajendran R, Sherry L, Nile C, Ramage G. New strategic insights into managing fungal biofilms. Front Microbiol 2015; 6:1077. [PMID: 26500623 PMCID: PMC4594024 DOI: 10.3389/fmicb.2015.01077] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 09/21/2015] [Indexed: 12/22/2022] Open
Abstract
Fungal infections have dramatically increased in the last decades in parallel with an increase of populations with impaired immunity, resulting from medical conditions such as cancer, transplantation, or other chronic diseases. Such opportunistic infections result from a complex relationship between fungi and host, and can range from self-limiting to chronic or life-threatening infections. Modern medicine, characterized by a wide use of biomedical devices, offers new niches for fungi to colonize and form biofilm communities. The capability of fungi to form biofilms is well documented and associated with increased drug tolerance and resistance. In addition, biofilm formation facilitates persistence in the host promoting a persistent inflammatory condition. With a limited availability of antifungals within our arsenal, new therapeutic approaches able to address both host and pathogenic factors that promote fungal disease progression, i.e., chronic inflammation and biofilm formation, could represent an advantage in the clinical setting. In this paper we discuss the antifungal properties of myriocin, fulvic acid, and acetylcholine in light of their already known anti-inflammatory activity and as candidate dual action therapeutics to treat opportunistic fungal infections.
Collapse
Affiliation(s)
- Elisa Borghi
- Laboratory of Microbiology, Department of Health Sciences, Università degli Studi di Milano , Milan, Italy
| | - Giulia Morace
- Laboratory of Microbiology, Department of Health Sciences, Università degli Studi di Milano , Milan, Italy
| | - Francesca Borgo
- Laboratory of Microbiology, Department of Health Sciences, Università degli Studi di Milano , Milan, Italy
| | - Ranjith Rajendran
- Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, University of Glasgow , Glasgow, UK
| | - Leighann Sherry
- Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, University of Glasgow , Glasgow, UK
| | - Christopher Nile
- Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, University of Glasgow , Glasgow, UK
| | - Gordon Ramage
- Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, University of Glasgow , Glasgow, UK
| |
Collapse
|
44
|
Cannon R, Holmes A. Learning the ABC of oral fungal drug resistance. Mol Oral Microbiol 2015; 30:425-37. [DOI: 10.1111/omi.12109] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2015] [Indexed: 01/07/2023]
Affiliation(s)
- R.D. Cannon
- Sir John Walsh Research Institute; University of Otago; Dunedin New Zealand
| | - A.R. Holmes
- Sir John Walsh Research Institute; University of Otago; Dunedin New Zealand
| |
Collapse
|
45
|
Hall RA. Dressed to impress: impact of environmental adaptation on the Candida albicans cell wall. Mol Microbiol 2015; 97:7-17. [PMID: 25846717 PMCID: PMC4973840 DOI: 10.1111/mmi.13020] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2015] [Indexed: 11/27/2022]
Abstract
Candida albicans is an opportunistic fungal pathogen of humans causing superficial mucosal infections and life‐threatening systemic disease. The fungal cell wall is the first point of contact between the invading pathogen and the host innate immune system. As a result, the polysaccharides that comprise the cell wall act as pathogen associated molecular patterns, which govern the host–pathogen interaction. The cell wall is dynamic and responsive to changes in the external environment. Therefore, the host environment plays a critical role in regulating the host–pathogen interaction through modulation of the fungal cell wall. This review focuses on how environmental adaptation modulates the cell wall structure and composition, and the subsequent impact this has on the innate immune recognition of C. albicans.
Collapse
Affiliation(s)
- Rebecca A Hall
- School of Biosciences, Institute of Microbiology and Infection, University of Birmingham, Edgbaston Park Road, Birmingham, B15 2TT, UK
| |
Collapse
|