1
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Anderson MZ, Dietz SM. Evolution and strain diversity advance exploration of Candida albicans biology. mSphere 2024:e0064123. [PMID: 39012122 DOI: 10.1128/msphere.00641-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/17/2024] Open
Abstract
Fungi were some of the earliest organismal systems used to explore mutational processes and its phenotypic consequences on members of a species. Yeasts that cause significant human disease were quickly incorporated into these investigations to define the genetic and phenotypic drivers of virulence. Among Candida species, Candida albicans has emerged as a model for studying genomic processes of evolution because of its clinical relevance, relatively small genome, and ability to tolerate complex chromosomal changes. Here, we describe major recent findings that used evolution of strains from defined genetic backgrounds to delineate mutational and adaptative processes and include how nascent exploration into naturally occurring variation is contributing to these conceptual frameworks. Ultimately, efforts to discern adaptive mechanisms used by C. albicans will continue to divulge new biology and can better inform treatment regimens for the increasing prevalence of fungal disease.
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Affiliation(s)
- Matthew Z Anderson
- Department of Medical Genetics, Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Siobhan M Dietz
- Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
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2
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Katsipoulaki M, Stappers MHT, Malavia-Jones D, Brunke S, Hube B, Gow NAR. Candida albicans and Candida glabrata: global priority pathogens. Microbiol Mol Biol Rev 2024; 88:e0002123. [PMID: 38832801 DOI: 10.1128/mmbr.00021-23] [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: 06/05/2024] Open
Abstract
SUMMARYA significant increase in the incidence of Candida-mediated infections has been observed in the last decade, mainly due to rising numbers of susceptible individuals. Recently, the World Health Organization published its first fungal pathogen priority list, with Candida species listed in medium, high, and critical priority categories. This review is a synthesis of information and recent advances in our understanding of two of these species-Candida albicans and Candida glabrata. Of these, C. albicans is the most common cause of candidemia around the world and is categorized as a critical priority pathogen. C. glabrata is considered a high-priority pathogen and has become an increasingly important cause of candidemia in recent years. It is now the second most common causative agent of candidemia in many geographical regions. Despite their differences and phylogenetic divergence, they are successful as pathogens and commensals of humans. Both species can cause a broad variety of infections, ranging from superficial to potentially lethal systemic infections. While they share similarities in certain infection strategies, including tissue adhesion and invasion, they differ significantly in key aspects of their biology, interaction with immune cells, host damage strategies, and metabolic adaptations. Here we provide insights on key aspects of their biology, epidemiology, commensal and pathogenic lifestyles, interactions with the immune system, and antifungal resistance.
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Affiliation(s)
- Myrto Katsipoulaki
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Mark H T Stappers
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Dhara Malavia-Jones
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Sascha Brunke
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
- Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Neil A R Gow
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
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3
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Jensen O, Trujillo E, Hanson L, Ost KS. Controlling Candida: immune regulation of commensal fungi in the gut. Infect Immun 2024:e0051623. [PMID: 38647290 DOI: 10.1128/iai.00516-23] [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] [Indexed: 04/25/2024] Open
Abstract
The intestinal microbiome harbors fungi that pose a significant risk to human health as opportunistic pathogens and drivers of inflammation. Inflammatory and autoimmune diseases are associated with dysbiotic fungal communities and the expansion of potentially pathogenic fungi. The gut is also the main reservoir for disseminated fungal infections. Immune interactions are critical for preventing commensal fungi from becoming pathogenic. Significant strides have been made in defining innate and adaptive immune pathways that regulate intestinal fungi, and these discoveries have coincided with advancements in our understanding of the fungal molecular pathways and effectors involved in both commensal colonization and pathogenesis within the gut. In this review, we will discuss immune interactions important for regulating commensal fungi, with a focus on how specific cell types and effectors interact with fungi to limit their colonization or pathogenic potential. This will include how innate and adaptive immune pathways target fungi and orchestrate antifungal immune responses, in addition to how secreted immune effectors, such as mucus and antimicrobial peptides, regulate fungal colonization and inhibit pathogenic potential. These immune interactions will be framed around our current understanding of the fungal effectors and pathways regulating colonization and pathogenesis within this niche. Finally, we highlight important unexplored mechanisms by which the immune system regulates commensal fungi in the gut.
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Affiliation(s)
- Owen Jensen
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Emma Trujillo
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Luke Hanson
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Kyla S Ost
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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4
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Alonso-Monge R, Cortés-Prieto I, Román E, Pla J. Morphogenetic transitions in the adaptation of Candida albicans to the mammalian gut. Microbes Infect 2024; 26:105253. [PMID: 37977323 DOI: 10.1016/j.micinf.2023.105253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 11/06/2023] [Accepted: 11/12/2023] [Indexed: 11/19/2023]
Abstract
Candida albicans is a pathobiont in humans that forms part of the mycobiota in healthy individuals and can cause different pathologies upon alterations of the host defenses. The mammalian gut is clinically relevant as this niche is the most common pool for bloodstream-derived infections. The ability of C. albicans to switch from yeast to hypha has been related to the commensal-to-pathogen transition and is, therefore, considered relevant in virulence. Recently, filaments have been implicated in the humoral response in the gut. C. albicans exhibits other morphologies that play different roles in pathogenicity and commensalism. This review focuses on the role of these morphological transitions in C. albicans proliferation and its establishment as a commensal in the mammalian gut, paying special attention to the transcription factors involved in their regulation.
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Affiliation(s)
- Rebeca Alonso-Monge
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza de Ramón y Cajal s/n, 28040 Madrid, Spain.
| | - Isabel Cortés-Prieto
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza de Ramón y Cajal s/n, 28040 Madrid, Spain.
| | - Elvira Román
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza de Ramón y Cajal s/n, 28040 Madrid, Spain.
| | - Jesús Pla
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza de Ramón y Cajal s/n, 28040 Madrid, Spain.
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5
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Wakade RS, Krysan DJ. Comparative dynamics of gene expression during in vitro and in vivo Candida albicans filamentation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.21.558874. [PMID: 37790536 PMCID: PMC10542175 DOI: 10.1101/2023.09.21.558874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Candida albicans is one of them most common causes of fungal disease in humans and is a commensal member of the human microbiome. The ability of C. albicans to cause disease is tightly correlated with its ability to undergo a morphological transition from budding yeast to a filamentous form (hyphae and pseudohyphae). This morphological transition is accompanied by the induction of a set of well characterized hyphae-associated genes and transcriptional regulators. To date, the vast majority of data regarding this process has been based on in vitro studies of filamentation using a range of inducing conditions. Recently, we developed an in vivo imaging approach that allows the direct characterization of morphological transition during mammalian infection. Here, we couple this imaging assay with in vivo expression profiling to characterize the time course of in vivo filamentation and the accompanying changes in gene expression. We also compare in vivo observations to in vitro filamentation using a medium (RPMI 1640 tissue culture medium with 10% bovine calf serum) widely used to mimic host conditions. From these data, we make the following conclusions regarding in vivo and in vitro filamentation. First, the transcriptional programs regulating filamentation are rapidly induced in vitro and in vivo. Second, the tempo of filamentation in vivo is prolonged relative to in vitro filamentation and the period of high expression of genes associated with that process is also prolonged. Third, hyphae are adapting to changing infection environments after filamentation has reached steady-state.
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Affiliation(s)
- Rohan S. Wakade
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City IA
| | - Damian J. Krysan
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City IA
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City IA
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6
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Puerner C, Vellanki S, Strauch JL, Cramer RA. Recent Advances in Understanding the Human Fungal Pathogen Hypoxia Response in Disease Progression. Annu Rev Microbiol 2023; 77:403-425. [PMID: 37713457 PMCID: PMC11034785 DOI: 10.1146/annurev-micro-032521-021745] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/17/2023]
Abstract
Fungal-mediated disease progression and antifungal drug efficacy are significantly impacted by the dynamic infection microenvironment. At the site of infection, oxygen often becomes limiting and induces a hypoxia response in both the fungal pathogen and host cells. The fungal hypoxia response impacts several important aspects of fungal biology that contribute to pathogenesis, virulence, antifungal drug susceptibility, and ultimately infection outcomes. In this review, we summarize recent advances in understanding the molecular mechanisms of the hypoxia response in the most common human fungal pathogens, discuss potential therapeutic opportunities, and highlight important areas for future research.
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Affiliation(s)
- Charles Puerner
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA;
| | - Sandeep Vellanki
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA;
| | - Julianne L Strauch
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA;
- Department of Biology, Dartmouth College, Hanover, New Hampshire, USA
| | - Robert A Cramer
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA;
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7
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Liu Z, Basso P, Hossain S, Liston SD, Robbins N, Whitesell L, Noble SM, Cowen LE. Multifactor transcriptional control of alternative oxidase induction integrates diverse environmental inputs to enable fungal virulence. Nat Commun 2023; 14:4528. [PMID: 37500616 PMCID: PMC10374912 DOI: 10.1038/s41467-023-40209-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 07/17/2023] [Indexed: 07/29/2023] Open
Abstract
Metabolic flexibility enables fungi to invade challenging host environments. In Candida albicans, a common cause of life-threatening infections in humans, an important contributor to flexibility is alternative oxidase (Aox) activity. Dramatic induction of this activity occurs under respiratory-stress conditions, which impair the classical electron transport chain (ETC). Here, we show that deletion of the inducible AOX2 gene cripples C. albicans virulence in mice by increasing immune recognition. To investigate further, we examined transcriptional regulation of AOX2 in molecular detail under host-relevant, ETC-inhibitory conditions. We found that multiple transcription factors, including Rtg1/Rtg3, Cwt1/Zcf11, and Zcf2, bind and regulate the AOX2 promoter, conferring thousand-fold levels of inducibility to AOX2 in response to distinct environmental stressors. Further dissection of this complex promoter revealed how integration of stimuli ranging from reactive species of oxygen, nitrogen, and sulfur to reduced copper availability is achieved at the transcriptional level to regulate AOX2 induction and enable pathogenesis.
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Affiliation(s)
- Zhongle Liu
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Pauline Basso
- UCSF Department of Microbiology & Immunology, San Francisco, CA, USA
| | - Saif Hossain
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Sean D Liston
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Luke Whitesell
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Suzanne M Noble
- UCSF Department of Microbiology & Immunology, San Francisco, CA, USA.
- UCSF Department of Medicine, Division of Infectious Diseases, San Francisco, CA, USA.
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.
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8
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Yang D, Zhang M, Su C, Dong B, Lu Y. Candida albicans exploits N-acetylglucosamine as a gut signal to establish the balance between commensalism and pathogenesis. Nat Commun 2023; 14:3796. [PMID: 37365160 DOI: 10.1038/s41467-023-39284-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 06/02/2023] [Indexed: 06/28/2023] Open
Abstract
Candida albicans is a benign member of gut microbiota, but also causes life-threatening disseminated infections, suggesting that this fungus commensalism has evolved with retention of virulence traits. Here we reveal that N-acetylglucosamine (GlcNAc) enables C. albicans to balance between commensalism and pathogenesis. Although GlcNAc catabolism is beneficial for commensal growth of C. albicans, deleting GlcNAc sensor-transducer Ngs1 confers enhanced fitness, indicating that GlcNAc signaling is detrimental to commensalism. Interestingly, addition of GlcNAc attenuates commensal fitness of gut-evolved C. albicans but retains its disease-causing potential. We further demonstrate that GlcNAc is a major inducer of hypha-associated transcription in the gut, which represents the key determinant for commensal-pathogenic equilibrium. In addition to yeast-to-hypha morphogenesis, we also identify other factors, including Sod5 and Ofi1, that contribute to the balance. Thus, C. albicans uses GlcNAc to build up a tradeoff between fungal programs supporting commensalism and virulence, which may explain its success as a commensal and pathogen.
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Affiliation(s)
- Dandan Yang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, 430072, China
| | - Mao Zhang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Chang Su
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, 430072, China
| | - Bin Dong
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, 430072, China
| | - Yang Lu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, TaiKang Center for Life and Medical Sciences, Wuhan University, Wuhan, 430072, China.
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9
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Wakade RS, Ristow LC, Wellington M, Krysan DJ. Intravital imaging-based genetic screen reveals the transcriptional network governing Candida albicans filamentation during mammalian infection. eLife 2023; 12:e85114. [PMID: 36847358 PMCID: PMC9995110 DOI: 10.7554/elife.85114] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 02/26/2023] [Indexed: 03/01/2023] Open
Abstract
Candida albicans is one of the most common human fungal pathogens. C. albicans pathogenesis is tightly linked to its ability to under a morphogenetic transition from typically budding yeast to filamentous forms of hyphae and pseudohyphae. Filamentous morphogenesis is the most intensively studied C. albicans virulence traits; however, nearly all of these studies have been based on in vitro induction of filamentation. Using an intravital imaging assay of filamentation during mammalian (mouse) infection, we have screened a library of transcription factor mutants to identify those that modulate both the initiation and maintenance of filamentation in vivo. We coupled this initial screen with genetic interaction analysis and in vivo transcription profiling to characterize the transcription factor network governing filamentation in infected mammalian tissue. Three core positive (Efg1, Brg1, and Rob1) and two core negative regulators (Nrg1 and Tup1) of filament initiation were identified. No previous systematic analysis of genes affecting the elongation step has been reported and we found that large set of transcription factors affect filament elongation in vivo including four (Hms1, Lys14, War1, Dal81) with no effect on in vitro elongation. We also show that the gene targets of initiation and elongation regulators are distinct. Genetic interaction analysis of the core positive and negative regulators revealed that the master regulator Efg1 primarily functions to mediate relief of Nrg1 repression and is dispensable for expression of hypha-associated genes in vitro and in vivo. Thus, our analysis not only provide the first characterization of the transcriptional network governing C. albicans filamentation in vivo but also revealed a fundamentally new mode of function for Efg1, one of the most widely studied C. albicans transcription factors.
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Affiliation(s)
- Rohan S Wakade
- Department of Pediatrics, Carver College of Medicine, University of IowaIowa CityUnited States
| | - Laura C Ristow
- Department of Pediatrics, Carver College of Medicine, University of IowaIowa CityUnited States
| | - Melanie Wellington
- Department of Pediatrics, Carver College of Medicine, University of IowaIowa CityUnited States
| | - Damian J Krysan
- Department of Pediatrics, Carver College of Medicine, University of IowaIowa CityUnited States
- Departments of Microbiology and Immunology, Carver College of Medicine, University of IowaIowa CityUnited States
- Molecular Physiology and Biophysics, Carver College of Medicine, University of IowaIowa CityUnited States
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10
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Cravener MV, Do E, May G, Zarnowski R, Andes DR, McManus CJ, Mitchell AP. Reinforcement amid genetic diversity in the Candida albicans biofilm regulatory network. PLoS Pathog 2023; 19:e1011109. [PMID: 36696432 PMCID: PMC9901766 DOI: 10.1371/journal.ppat.1011109] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 02/06/2023] [Accepted: 01/09/2023] [Indexed: 01/26/2023] Open
Abstract
Biofilms of the fungal pathogen Candida albicans include abundant long filaments called hyphae. These cells express hypha-associated genes, which specify diverse virulence functions including surface adhesins that ensure biofilm integrity. Biofilm formation, virulence, and hypha-associated gene expression all depend upon the transcription factor Efg1. This transcription factor has been characterized extensively in the C. albicans type strain SC5314 and derivatives, but only recently has its function been explored in other clinical isolates. Here we define a principal set of Efg1-responsive genes whose expression is significantly altered by an efg1Δ/Δ mutation across 17 clinical isolates. This principal gene set includes 68 direct Efg1 targets, whose 5' regions are bound by Efg1 in five clinical isolates, and 42 indirect Efg1 targets, whose 5' regions are not detectably bound by Efg1. Three direct Efg1 target genes encode transcription factors-BRG1, UME6, and WOR3 -whose increased expression in an efg1Δ/Δ mutant restores expression of multiple indirect and direct principal targets, as well as biofilm formation ability. Although BRG1 and UME6 are well known positive regulators of hypha-associated genes and biofilm formation, WOR3 is best known as an antagonist of Efg1 in the sexual mating pathway. We confirm the positive role of WOR3 in biofilm formation with the finding that a wor3Δ/Δ mutation impairs biofilm formation in vitro and in an in vivo biofilm model. Positive control of Efg1 direct target genes by other Efg1 direct target genes-BRG1, UME6, and WOR3 -may buffer principal Efg1-responsive gene expression against the impact of genetic variation in the C. albicans species.
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Affiliation(s)
- Max V. Cravener
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
| | - Eunsoo Do
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
| | - Gemma May
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Robert Zarnowski
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, Wisconsin, United States of America
| | - David R. Andes
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, Wisconsin, United States of America
| | - C. Joel McManus
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Aaron P. Mitchell
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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11
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He J, Ye Y, Zhang D, Yao K, Zhou M. Visualized Gallium/Lyticase-Integrated Antifungal Strategy for Fungal Keratitis Treatment. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2206437. [PMID: 36177690 DOI: 10.1002/adma.202206437] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 09/19/2022] [Indexed: 06/16/2023]
Abstract
Fungal keratitis has been one of the common corneal infections that causes blindness, but an effective antifungal strategy remains a challenge. The exopolysaccharides both in the fungal cell walls and biofilms are a key that acts as a permeation barrier to weaken the therapeutic effect of antifungal agents. Herein, lyticase and gallium ions co-integrated nanosystems (MLPGa) are presented that can degrade exopolysaccharides and then effectively eradicate both planktonic Candida albicans and mature biofilms. The potential antifungal mechanism involves reactive oxygen species (ROS) production and metabolic interference of antioxidant-related genes, exopolysaccharide-related genes, iron-ion-utilization-related genes, fungal/biofilm-development-related genes, and virulence genes. Meanwhile, the Raman signals generated by the chelation between the nanosystems and the gallium ions provide a real-time visualization tool to monitor Ga release. Finally, the MLPGa-based antifungal strategy with good biocompatibility achieves a satisfactory therapeutic effect in a fungal keratitis mouse model. This study provides a unique approach to the effective treatment of fungal keratitis in clinical practice.
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Affiliation(s)
- Jian He
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China
- Institute of Translational Medicine, Zhejiang University, Hangzhou, 310009, China
| | - Yang Ye
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Zhejiang University, Hangzhou, 310009, China
| | - Dongxiao Zhang
- Institute of Translational Medicine, Zhejiang University, Hangzhou, 310009, China
| | - Ke Yao
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Zhejiang University, Hangzhou, 310009, China
| | - Min Zhou
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, China
- Institute of Translational Medicine, Zhejiang University, Hangzhou, 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Zhejiang University, Hangzhou, 310009, China
- State Key Laboratory of Modern Optical Instrumentations, Zhejiang University, Hangzhou, 310058, China
- Research Center for Life Science and Human Health, Binjiang Institute of Zhejiang University, Hangzhou, 310053, China
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12
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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.
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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
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13
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Glazier VE. EFG1, Everyone’s Favorite Gene in Candida albicans: A Comprehensive Literature Review. Front Cell Infect Microbiol 2022; 12:855229. [PMID: 35392604 PMCID: PMC8980467 DOI: 10.3389/fcimb.2022.855229] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 02/24/2022] [Indexed: 12/18/2022] Open
Abstract
Candida sp. are among the most common fungal commensals found in the human microbiome. Although Candida can be found residing harmlessly on the surface of the skin and mucosal membranes, these opportunistic fungi have the potential to cause superficial skin, nail, and mucus membrane infections as well as life threatening systemic infections. Severity of infection is dependent on both fungal and host factors including the immune status of the host. Virulence factors associated with Candida sp. pathogenicity include adhesin proteins, degradative enzymes, phenotypic switching, and morphogenesis. A central transcriptional regulator of morphogenesis, the transcription factor Efg1 was first characterized in Candida albicans in 1997. Since then, EFG1 has been referenced in the Candida literature over three thousand times, with the number of citations growing daily. Arguably one of the most well studied genes in Candida albicans, EFG1 has been referenced in nearly all contexts of Candida biology from the development of novel therapeutics to white opaque switching, hyphae morphology to immunology. In the review that follows we will synthesize the research that has been performed on this extensively studied transcription factor and highlight several important unanswered questions.
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Li XV, Leonardi I, Putzel GG, Semon A, Fiers WD, Kusakabe T, Lin WY, Gao IH, Doron I, Gutierrez-Guerrero A, DeCelie MB, Carriche GM, Mesko M, Yang C, Naglik JR, Hube B, Scherl EJ, Iliev ID. Immune regulation by fungal strain diversity in inflammatory bowel disease. Nature 2022; 603:672-678. [PMID: 35296857 PMCID: PMC9166917 DOI: 10.1038/s41586-022-04502-w] [Citation(s) in RCA: 108] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 02/02/2022] [Indexed: 12/21/2022]
Abstract
The fungal microbiota (mycobiota) is an integral part of the complex multikingdom microbial community colonizing the mammalian gastrointestinal tract and has an important role in immune regulation1-6. Although aberrant changes in the mycobiota have been linked to several diseases, including inflammatory bowel disease3-9, it is currently unknown whether fungal species captured by deep sequencing represent living organisms and whether specific fungi have functional consequences for disease development in affected individuals. Here we developed a translational platform for the functional analysis of the mycobiome at the fungal-strain- and patient-specific level. Combining high-resolution mycobiota sequencing, fungal culturomics and genomics, a CRISPR-Cas9-based fungal strain editing system, in vitro functional immunoreactivity assays and in vivo models, this platform enables the examination of host-fungal crosstalk in the human gut. We discovered a rich genetic diversity of opportunistic Candida albicans strains that dominate the colonic mucosa of patients with inflammatory bowel disease. Among these human-gut-derived isolates, strains with high immune-cell-damaging capacity (HD strains) reflect the disease features of individual patients with ulcerative colitis and aggravated intestinal inflammation in vivo through IL-1β-dependent mechanisms. Niche-specific inflammatory immunity and interleukin-17A-producing T helper cell (TH17 cell) antifungal responses by HD strains in the gut were dependent on the C. albicans-secreted peptide toxin candidalysin during the transition from a benign commensal to a pathobiont state. These findings reveal the strain-specific nature of host-fungal interactions in the human gut and highlight new diagnostic and therapeutic targets for diseases of inflammatory origin.
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Affiliation(s)
- Xin V Li
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Irina Leonardi
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Gregory G Putzel
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Alexa Semon
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - William D Fiers
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Takato Kusakabe
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Woan-Yu Lin
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
- Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Iris H Gao
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
- Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Itai Doron
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Alejandra Gutierrez-Guerrero
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Meghan B DeCelie
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Guilhermina M Carriche
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Marissa Mesko
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Chen Yang
- Department of Pathology, Yale School of Medicine, Yale University, New Haven, CT, USA
| | - Julian R Naglik
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, London, UK
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knoell Institute, Jena, Germany
- Institute of Microbiology, FriedrichSchiller University, Jena, Germany
| | - Ellen J Scherl
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
- The Jill Roberts Center for Inflammatory Bowel Disease, Weill Cornell Medicine, New York, NY, USA
| | - Iliyan D Iliev
- Gastroenterology and Hepatology Division, Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA.
- The Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA.
- Immunology and Microbial Pathogenesis Program, Weill Cornell Graduate School of Medical Sciences, Weill Cornell Medicine, Cornell University, New York, NY, USA.
- Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, New York, NY, USA.
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Abstract
The fungus Candida albicans is a ubiquitous member of the human gut microbiota. Hundreds or thousands of bacterial taxa reside together with this fungus in the intestine, creating a milieu with myriad opportunities for inter-kingdom interactions. Indeed, recent studies examining the broader composition - that is, monitoring not only bacteria but also the often neglected fungal component - of the gut microbiota hint that there are significant interdependencies between fungi and bacteria. Gut bacteria closely associate with C. albicans cells in the colon, break down and feed on complex sugars decorating the fungal cell wall, and shape the intestinal microhabitats occupied by the fungus. Peptidoglycan subunits released by bacteria upon antibiotic treatment can promote C. albicans dissemination from the intestine, seeding bloodstream infections that often become life-threatening. Elucidating the principles that govern the fungus-bacteria interplay may open the door to novel approaches to prevent C. albicans infections originating in the gut.
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Affiliation(s)
- J. Christian Pérez
- Department of Microbiology and Molecular Genetics, McGovern Medical School, the University of Texas Health Science Center at Houston, Houston, USA,CONTACT J.Christian Pérez Department of Microbiology and Molecular Genetics, McGovern Medical School, the University of Texas Health Science Center at Houston, Houston, USA
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McDonough LD, Mishra AA, Tosini N, Kakade P, Penumutchu S, Liang SH, Maufrais C, Zhai B, Taur Y, Belenky P, Bennett RJ, Hohl TM, Koh AY, Ene IV. Candida albicans Isolates 529L and CHN1 Exhibit Stable Colonization of the Murine Gastrointestinal Tract. mBio 2021; 12:e0287821. [PMID: 34724818 PMCID: PMC8561340 DOI: 10.1128/mbio.02878-21] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 10/06/2021] [Indexed: 02/06/2023] Open
Abstract
Candida albicans is a pathobiont that colonizes multiple niches in the body including the gastrointestinal (GI) tract but is also responsible for both mucosal and systemic infections. Despite its prevalence as a human commensal, the murine GI tract is generally refractory to colonization with the C. albicans reference isolate SC5314. Here, we identify two C. albicans isolates, 529L and CHN1, that stably colonize the murine GI tract in three different animal facilities under conditions where SC5314 is lost from this niche. Analysis of the bacterial microbiota did not show notable differences among mice colonized with the three C. albicans strains. We compared the genotypes and phenotypes of these three strains and identified thousands of single nucleotide polymorphisms (SNPs) and multiple phenotypic differences, including their ability to grow and filament in response to nutritional cues. Despite striking filamentation differences under laboratory conditions, however, analysis of cell morphology in the GI tract revealed that the three isolates exhibited similar filamentation properties in this in vivo niche. Notably, we found that SC5314 is more sensitive to the antimicrobial peptide CRAMP, and the use of CRAMP-deficient mice modestly increased the ability of SC5314 to colonize the GI tract relative to CHN1 and 529L. These studies provide new insights into how strain-specific differences impact C. albicans traits in the host and advance CHN1 and 529L as relevant strains to study C. albicans pathobiology in its natural host niche. IMPORTANCE Understanding how fungi colonize the GI tract is increasingly recognized as highly relevant to human health. The animal models used to study Candida albicans commensalism commonly rely on altering the host microbiome (via antibiotic treatment or defined diets) to establish successful GI colonization by the C. albicans reference isolate SC5314. Here, we characterize two C. albicans isolates that can colonize the murine GI tract without antibiotic treatment and can therefore be used as tools for studying fungal commensalism. Importantly, experiments were replicated in three different animal facilities and utilized three different mouse strains. Differential colonization between fungal isolates was not associated with alterations in the bacterial microbiome but rather with distinct responses to CRAMP, a host antimicrobial peptide. This work emphasizes the importance of C. albicans intraspecies variation as well as host antimicrobial defense mechanisms in defining the outcome of commensal interactions.
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Affiliation(s)
- Liam D. McDonough
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, Connecticut, USA
| | - Animesh A. Mishra
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Nicholas Tosini
- Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Pallavi Kakade
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| | - Swathi Penumutchu
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| | - Shen-Huan Liang
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| | | | - Bing Zhai
- Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Ying Taur
- Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Department of Medicine, Weill Cornell Medical College, New York, New York, USA
| | - Peter Belenky
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| | - Richard J. Bennett
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
| | - Tobias M. Hohl
- Infectious Disease Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Immunology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Department of Medicine, Weill Cornell Medical College, New York, New York, USA
| | - Andrew Y. Koh
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Harold C. Simmons Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Iuliana V. Ene
- Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island, USA
- Department of Mycology, Institut Pasteur, Paris, France
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Norris HL, Kumar R, Edgerton M. A Novel Role for Histatin 5 in Combination with Zinc to Promote Commensalism in C. albicans Survivor Cells. Pathogens 2021; 10:pathogens10121609. [PMID: 34959564 PMCID: PMC8703888 DOI: 10.3390/pathogens10121609] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/03/2021] [Accepted: 12/07/2021] [Indexed: 12/18/2022] Open
Abstract
Candida albicans is maintained as a commensal by immune mechanisms at the oral epithelia. Oral antifungal peptide Histatin 5 (Hst 5) may function in innate immunity, but the specific role Hst 5 plays in C. albicans commensalism is unclear. Since Zn-binding potentiates the candidacidal activity of Hst 5, we hypothesized that Hst 5+Zn would elicit a unique fungal stress response to shape interactions between C. albicans and oral epithelial cells (OECs). We found that Hst 5+Zn but not Hst 5 alone resulted in the activation of cell wall integrity (CWI) signaling, and deletion mutants were then used to determine that CWI-mediated chitin synthesis was protective against killing. Using flow cytometry, we confirmed that Hst 5+Zn-treated cells had significantly elevated levels of cell-wall chitin, mannan and β-1,3 glucan compared to Hst 5-treated cells. We then tested the activation of host signaling components involved in C. albicans cell-wall recognition. The immunoblot assay of C. albicans-exposed oral epithelial cells showed increased activation of EphA2 and NF-κB but not EGFR. Interestingly, C. albicans treated with Hst 5+Zn induced the global suppression of pro-inflammatory cytokine release from OECs, but an increase in negative regulator IL-10. Hst 5+Zn-treated cells were more adherent but ultimately less invasive to OECs than control cells, thus indicating lowered virulence. Therefore, Hst 5+Zn-treated C. albicans cells are discerned by epithelial monolayers, but are less virulent and promote anti-inflammatory signaling, suggesting that Hst 5+Zn in combination could play a role in regulating commensalism of oral C. albicans through cell wall reorganization.
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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.
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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
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Commensalism instead of sex? Adapting mating to live in the gut. Cell Host Microbe 2021; 29:856-858. [PMID: 34111393 DOI: 10.1016/j.chom.2021.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In this issue of Cell Host & Microbe, Witchley et al. (2021) describe a rewired transcriptional network that reveals how the human fungal pathogen Candida albicans favors commensalism over sexual reproduction in the host environment.
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