1
|
Yadav KK, Prakash O. Protocol for enriching, isolating, and testing drug susceptibility of facultative anaerobic fungi. STAR Protoc 2024; 5:103247. [PMID: 39110598 PMCID: PMC11362773 DOI: 10.1016/j.xpro.2024.103247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 06/21/2024] [Accepted: 07/18/2024] [Indexed: 09/02/2024] Open
Abstract
Research on fungi under anaerobic conditions is limited but crucial for understanding their ecological and pathological impacts. Here, we present a protocol for enriching, isolating, and characterizing anaerobic fungi from environmental and clinical samples. We also describe steps for evaluating the anaerobic growth potential and drug susceptibility of fungal pathogens. This protocol can contribute to the need for initiating effective antifungal therapy to address and manage fungal infections or mycosis in oxygen-limited environments. For complete details on the use and execution of this protocol, please refer to Yadav et al.1.
Collapse
Affiliation(s)
- Krishna K Yadav
- National Centre for Microbial Resource (NCMR), National Centre for Cell Science (NCCS), Pune, Maharashtra 411007, India; Symbiosis Centre for Waste Resource Management (SCWRM), Symbiosis International (Deemed University), Lavale, Pune 412115, India; National Centre for Cell Sciences, NCCS Complex, University of Pune Campus, Pune University Road, Ganeshkhind, Pune, Maharashtra 411007, India
| | - Om Prakash
- National Centre for Microbial Resource (NCMR), National Centre for Cell Science (NCCS), Pune, Maharashtra 411007, India; Symbiosis Centre for Climate Change and Sustainability (SCCCS), Symbiosis International (Deemed University), Lavale, Pune 412115, India; National Centre for Cell Sciences, NCCS Complex, University of Pune Campus, Pune University Road, Ganeshkhind, Pune, Maharashtra 411007, India.
| |
Collapse
|
2
|
Tebbji F, Menon ACT, Khemiri I, St-Cyr DJ, Villeneuve L, Vincent AT, Sellam A. Small molecule inhibitors of fungal Δ(9) fatty acid desaturase as antifungal agents against Candida auris. Front Cell Infect Microbiol 2024; 14:1434939. [PMID: 39282497 PMCID: PMC11392922 DOI: 10.3389/fcimb.2024.1434939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2024] [Accepted: 08/05/2024] [Indexed: 09/19/2024] Open
Abstract
Candida auris has emerged as a significant healthcare-associated pathogen due to its multidrug-resistant nature. Ongoing constraints in the discovery and provision of new antifungals create an urgent imperative to design effective remedies to this pressing global blight. Herein, we screened a chemical library and identified aryl-carbohydrazide analogs with potent activity against both C. auris and the most prevalent human fungal pathogen, C. albicans. SPB00525 [N'-(2,6-dichlorophenyl)-5-nitro-furan-2-carbohydrazide] exhibited potent activity against different strains that were resistant to standard antifungals. Using drug-induced haploinsufficient profiling, transcriptomics and metabolomic analysis, we uncovered that Ole1, a Δ(9) fatty acid desaturase, is the likely target of SPB00525. An analog of the latter, HTS06170 [N'-(2,6-dichlorophenyl)-4-methyl-1,2,3-thiadiazole-5-carbohydrazide], had a superior antifungal activity against both C. auris and C. albicans. Both SPB00525 and HTS06170 act as antivirulence agents and inhibited the invasive hyphal growth and biofilm formation of C. albicans. SPB00525 and HTS06170 attenuated fungal damage to human enterocytes and ameliorate the survival of Galleria mellonella larvae used as systemic candidiasis model. These data suggest that inhibiting fungal Δ(9) fatty acid desaturase activity represents a potential therapeutic approach for treating fungal infection caused by the superbug C. auris and the most prevalent human fungal pathogen, C. albicans.
Collapse
Affiliation(s)
- Faiza Tebbji
- Montreal Heart Institute/Institut de Cardiologie de Montréal, Université de Montréal, Montreal, QC, Canada
| | - Anagha C T Menon
- Montreal Heart Institute/Institut de Cardiologie de Montréal, Université de Montréal, Montreal, QC, Canada
- Department of Microbiology, Infectious Diseases and Immunology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Inès Khemiri
- Montreal Heart Institute/Institut de Cardiologie de Montréal, Université de Montréal, Montreal, QC, Canada
- Department of Microbiology, Infectious Diseases and Immunology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Daniel J St-Cyr
- Institute for Research in Immunology and Cancer (IRIC), Department of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Louis Villeneuve
- Montreal Heart Institute/Institut de Cardiologie de Montréal, Université de Montréal, Montreal, QC, Canada
| | - Antony T Vincent
- Department of Animal Sciences, Université Laval, Quebec City, QC, Canada
- Institute of Integrative and Systems Biology, Université Laval, Quebec City, QC, Canada
| | - Adnane Sellam
- Montreal Heart Institute/Institut de Cardiologie de Montréal, Université de Montréal, Montreal, QC, Canada
- Department of Microbiology, Infectious Diseases and Immunology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| |
Collapse
|
3
|
Khemiri I, Tebbji F, Burgain A, Sellam A. Regulation of copper uptake by the SWI/SNF chromatin remodeling complex in Candida albicans affects susceptibility to antifungal and oxidative stresses under hypoxia. FEMS Yeast Res 2024; 24:foae018. [PMID: 38760885 PMCID: PMC11160329 DOI: 10.1093/femsyr/foae018] [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] [Received: 03/18/2024] [Revised: 05/13/2024] [Accepted: 05/16/2024] [Indexed: 05/20/2024] Open
Abstract
Candida albicans is a human colonizer and also an opportunistic yeast occupying different niches that are mostly hypoxic. While hypoxia is the prevalent condition within the host, the machinery that integrates oxygen status to tune the fitness of fungal pathogens remains poorly characterized. Here, we uncovered that Snf5, a subunit of the chromatin remodeling complex SWI/SNF, is required to tolerate antifungal stress particularly under hypoxia. RNA-seq profiling of snf5 mutant exposed to amphotericin B and fluconazole under hypoxic conditions uncovered a signature that is reminiscent of copper (Cu) starvation. We found that under hypoxic and Cu-starved environments, Snf5 is critical for preserving Cu homeostasis and the transcriptional modulation of the Cu regulon. Furthermore, snf5 exhibits elevated levels of reactive oxygen species and an increased sensitivity to oxidative stress principally under hypoxia. Supplementing growth medium with Cu or increasing gene dosage of the Cu transporter CTR1 alleviated snf5 growth defect and attenuated reactive oxygen species levels in response to antifungal challenge. Genetic interaction analysis suggests that Snf5 and the bona fide Cu homeostasis regulator Mac1 function in separate pathways. Together, our data underlined a unique role of SWI/SNF complex as a potent regulator of Cu metabolism and antifungal stress under hypoxia.
Collapse
Affiliation(s)
- Inès Khemiri
- Montreal Heart Institute/Institut de Cardiologie de Montréal, Université de Montréal, 5000 Rue Bélanger, Montréal, QC H1T 1C8, Canada
| | - Faiza Tebbji
- Montreal Heart Institute/Institut de Cardiologie de Montréal, Université de Montréal, 5000 Rue Bélanger, Montréal, QC H1T 1C8, Canada
| | - Anaïs Burgain
- Department of Microbiology, Infectious Diseases and Immunology, Faculty of Medicine, Université Laval, Quebec City, QC, Canada
| | - Adnane Sellam
- Montreal Heart Institute/Institut de Cardiologie de Montréal, Université de Montréal, 5000 Rue Bélanger, Montréal, QC H1T 1C8, Canada
- Department of Microbiology, Infectious Diseases and Immunology, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada
| |
Collapse
|
4
|
Wang JJT, Steenwyk JL, Brem RB. Natural trait variation across Saccharomycotina species. FEMS Yeast Res 2024; 24:foae002. [PMID: 38218591 PMCID: PMC10833146 DOI: 10.1093/femsyr/foae002] [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] [Received: 06/27/2023] [Revised: 10/13/2023] [Accepted: 01/12/2024] [Indexed: 01/15/2024] Open
Abstract
Among molecular biologists, the group of fungi called Saccharomycotina is famous for its yeasts. These yeasts in turn are famous for what they have in common-genetic, biochemical, and cell-biological characteristics that serve as models for plants and animals. But behind the apparent homogeneity of Saccharomycotina species lie a wealth of differences. In this review, we discuss traits that vary across the Saccharomycotina subphylum. We describe cases of bright pigmentation; a zoo of cell shapes; metabolic specialties; and species with unique rules of gene regulation. We discuss the genetics of this diversity and why it matters, including insights into basic evolutionary principles with relevance across Eukarya.
Collapse
Affiliation(s)
- Johnson J -T Wang
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Jacob L Steenwyk
- Howard Hughes Medical Institute and Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Rachel B Brem
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| |
Collapse
|
5
|
Abe M, Kinjo Y, Koshikawa T, Miyazaki Y. Basic Research on Candida Species. Med Mycol J 2024; 65:67-74. [PMID: 39218649 DOI: 10.3314/mmj.24.006] [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] [Indexed: 09/04/2024]
Abstract
Candida species are common human pathogens that cause a wide range of diseases ranging from superficial to invasive candidiasis. However, basic studies focusing on the mechanisms underlying these diseases are limited. This article reviews our previous research on the mechanisms of superficial and invasive candidiasis, the virulence of Candida species, and Candida species fitness to hosts. Regarding invasive candidiasis, we focused on two types of infections: ocular candidiasis and endogenous candidiasis from the gastrointestinal tract. Using an established ocular candidiasis mouse model, along with retrospective epidemiological research, we found a strong association between Candida albicans and ocular candidiasis. Regarding endogenous candidiasis, research using Candida auris indicated that invasive strains had a higher capability for gastrointestinal tract colonization and showed greater dissemination compared with non-invasive strains. In terms of superficial candidiasis, we focused on the defense mechanism in vulvovaginal candidiasis. The results suggested that stimulated invariant natural killer T cells played a protective role against C. albicans vaginal infection and might be a therapeutic target for vulvovaginal candidiasis. Concerning Candida species fitness, we focused on environmental factors, particularly oxygen concentration, and evaluated biofilm formation under various oxygen concentrations, revealing that each Candida species favored different oxygen concentrations. In particular, Candida tropicalis showed greater biofilm formation under hypoxic conditions. Our research revealed several insights for understanding the exact mechanisms of candidiasis, which might lead to better control of Candida species infections and appropriate treatment.
Collapse
Affiliation(s)
- Masahiro Abe
- Department of Fungal Infection, National Institute of Infectious Diseases
| | - Yuki Kinjo
- Department of Bacteriology, The Jikei University School of Medicine
- Jikei Center for Biofilm Science and Technology, The Jikei University School of Medicine
| | - Takuro Koshikawa
- Department of Fungal Infection, National Institute of Infectious Diseases
- Department of Microbiology, St. Marianna University School of Medicine
| | | |
Collapse
|
6
|
Yadav KK, Nimonkar Y, Green SJ, Dewala S, Dhanorkar MN, Sharma R, Rale VR, Prakash O. Anaerobic growth and drug susceptibility of versatile fungal pathogen Scedosporium apiospermum. iScience 2023; 26:108304. [PMID: 37965151 PMCID: PMC10641749 DOI: 10.1016/j.isci.2023.108304] [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: 08/08/2023] [Revised: 10/11/2023] [Accepted: 10/20/2023] [Indexed: 11/16/2023] Open
Abstract
Although severe cases of invasive mycoses of different hypoxic and anoxic body parts have been reported, growth and drug susceptibility of fungal pathogens under anaerobic conditions remains understudied. The current study evaluated anaerobic growth potential and drug susceptibility of environmental Scedosporium apiospermum isolates under aerobic and anaerobic conditions. All tested strains showed equivalent growth and higher sensitivity to tested antifungal drugs under anaerobic conditions with lower minimum inhibitory concentration (MIC) as compared to aerobic conditions. Antifungal azoles were effective against isolates under both aerobic and anaerobic conditions. Most strains were resistant to antifungal echinocandins and polyenes under aerobic conditions but exhibited sensitivity under anaerobic conditions. This study provides evidence that resistance of S. apiospermum to antifungal drugs varies with oxygen concentration and availability and suggests re-evaluating clinical breakpoints for antifungal compounds to treat invasive fungal infections more effectively.
Collapse
Affiliation(s)
- Krishna K. Yadav
- National Centre for Microbial Resource (NCMR), National Centre for Cell Science (NCCS), Pune, Maharashtra 411007, India
- Symbiosis Centre for Waste Resource Management (SCWRM), Symbiosis International, (Deemed University), Lavale, Pune 412115, India
| | - Yogesh Nimonkar
- National Centre for Microbial Resource (NCMR), National Centre for Cell Science (NCCS), Pune, Maharashtra 411007, India
| | - Stefan J. Green
- Department of Internal Medicine, Division of Infectious Diseases, Rush University Medical Center, Chicago, IL 60607, USA
| | - Sahabram Dewala
- National Centre for Microbial Resource (NCMR), National Centre for Cell Science (NCCS), Pune, Maharashtra 411007, India
| | - Manikprabhu N. Dhanorkar
- Symbiosis Centre for Waste Resource Management (SCWRM), Symbiosis International, (Deemed University), Lavale, Pune 412115, India
| | - Rohit Sharma
- Department of Life Science and Biological Science, IES University, Bhopal, Madhya Pradesh 462 044, India
| | - Vinay R. Rale
- Symbiosis Centre for Research and Innovation (SCRI), Symbiosis International, (Deemed University), Lavale, Pune 412115, India
| | - Om Prakash
- National Centre for Microbial Resource (NCMR), National Centre for Cell Science (NCCS), Pune, Maharashtra 411007, India
- Symbiosis Centre for Climate Change and Sustainability (SCCCS), Symbiosis International, (Deemed University), Lavale, Pune 412115, India
| |
Collapse
|
7
|
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.
Collapse
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;
| |
Collapse
|
8
|
Zhao X, He Z, Gao Y, Kan Y, Jiao Y, Liu Y, Huang S, Luo Z, Zhang Y. Sterol Regulatory Element-Binding Protein, BbSre1, Controls Oxidative Stress Response, Peroxisome Division, and Lipid Homeostasis in an Insect Fungal Pathogen. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:12250-12263. [PMID: 37493643 DOI: 10.1021/acs.jafc.3c02568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
Sterol regulatory element-binding protein, Sre1, regulates sterol biosynthesis, lipid metabolism, hypoxia adaptation, and virulence in some fungi, even though its roles are varied in fungal species. However, few studies report its other functions in fungi. Here, we report novel roles of Sre1 homolog, BbSre1, in the insect fungal pathogen, Beauveria bassiana, that regulates oxidative stress response, peroxisome division, and redox homeostasis. The gene disruption stain showed increased sensitivity to oxidative stress, which was in line with oxidative stress-induced-BbSre1 nuclear import and control of antioxidant and detoxification-involved genes. The gene mutation also inhibited peroxisome division, affected redox homeostasis, and impaired lipid/fatty acid metabolism and sterol biosynthesis, which was verified by downregulation of their associated genes. These data broaden our understanding of role of Sre1, which regulates peroxisome division, antioxidant, and detoxification-involved genes for control of redox homeostasis and oxidative stress response that links to lipid/fatty acid metabolism and sterol biosynthesis.
Collapse
Affiliation(s)
- Xin Zhao
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing 400715, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Zhangjiang He
- Biochemical Engineering Center of Guizhou Province, Guizhou University, Guiyang 50025, China
| | - Yifei Gao
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing 400715, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Yanze Kan
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing 400715, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Yufei Jiao
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing 400715, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Yunxia Liu
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing 400715, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Shuaishuai Huang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing 400715, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Zhibing Luo
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing 400715, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| | - Yongjun Zhang
- Key Laboratory of Agricultural Biosafety and Green Production of Upper Yangtze River (Ministry of Education), College of Plant Protection, Southwest University, Chongqing 400715, China
- Key Laboratory of Entomology and Pest Control Engineering, Academy of Agricultural Sciences, Southwest University, Chongqing 400715, P. R. China
| |
Collapse
|
9
|
Silva AM, Pedrini N, Pupin B, Roberts DW, Rangel DEN. Asphyxiation of Metarhizium robertsii during mycelial growth produces conidia with increased stress tolerance via increased expression of stress-related genes. Fungal Biol 2023; 127:1209-1217. [PMID: 37495310 DOI: 10.1016/j.funbio.2023.01.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 01/07/2023] [Accepted: 01/17/2023] [Indexed: 01/20/2023]
Abstract
Little is known about the impact of hypoxia and anoxia during mycelial growth on tolerance to different stress conditions of developing fungal conidia. Conidia of the insect-pathogenic fungus Metarhizium robertsii were produced on potato dextrose agar (PDA) medium under normoxia (control = normal oxygen concentrations), continuous hypoxia, and transient anoxia, as well as minimal medium under normoxia. The tolerance of the conidia produced under these different conditions was evaluated in relation to wet heat (heat stress), menadione (oxidative stress), potassium chloride (osmotic stress), UV radiation, and 4-nitroquinoline-1-oxide (=4-NQO genotoxic stress). Growth under hypoxic condition induced higher conidial tolerance of M. robertsii to menadione, KCl, and UV radiation. Transient anoxic condition induced higher conidial tolerance to KCl and UV radiation. Nutritional stress (i.e., minimal medium) induced higher conidial tolerance to heat, menadione, KCl, and UV radiation. However, neither of these treatments induced higher tolerance to 4-NQO. The gene hsp30 and hsp101 encoding a heat shock protein was upregulated under anoxic condition. In conclusion, growth under hypoxia and anoxia produced conidia with higher stress tolerances than conidia produced in normoxic condition. The nutritive stress generated by minimal medium, however, induced much higher stress tolerances. This condition also caused the highest level of gene expression in the hsp30 and hsp101 genes. Thus, the conidia produced under nutritive stress, hypoxia, and anoxia had greater adaptation to stress.
Collapse
Affiliation(s)
| | - Nicolás Pedrini
- Instituto de Investigaciones Bioquímicas de La Plata (CONICET CCT La Plata-UNLP), Universidad Nacional de La Plata, La Plata, 1900, Argentina
| | - Breno Pupin
- Centro de Ciência do Sistema Terrestre, Instituto Nacional de Pesquisa Espaciais - INPE, São José dos Campos, SP, 12227-010, Brazil
| | - Donald W Roberts
- Department of Biology, Utah State University, Logan, UT, 84322-5305, USA
| | - Drauzio E N Rangel
- Universidade Tecnológica Federal do Paraná (UTFPR), 85660-000, Dois Vizinhos, PR, Brazil.
| |
Collapse
|
10
|
Zangl I, Beyer R, Gattesco A, Labuda R, Pap IJ, Strauss J, Schüller C. Limosilactobacillus fermentum Limits Candida glabrata Growth by Ergosterol Depletion. Microbiol Spectr 2023; 11:e0332622. [PMID: 36802215 PMCID: PMC10100998 DOI: 10.1128/spectrum.03326-22] [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: 11/18/2022] [Accepted: 01/27/2023] [Indexed: 02/23/2023] Open
Abstract
Candida glabrata is a human-associated opportunistic fungal pathogen. It shares its niche with Lactobacillus spp. in the gastrointestinal and vaginal tract. In fact, Lactobacillus species are thought to competitively prevent Candida overgrowth. We investigated the molecular aspects of this antifungal effect by analyzing the interaction of C. glabrata strains with Limosilactobacillus fermentum. From a collection of clinical C. glabrata isolates, we identified strains with different sensitivities to L. fermentum in coculture. We analyzed the variation of their expression pattern to isolate the specific response to L. fermentum. C. glabrata-L. fermentum coculture induced genes associated with ergosterol biosynthesis, weak acid stress, and drug/chemical stress. L. fermentum coculture depleted C. glabrata ergosterol. The reduction of ergosterol was dependent on the Lactobacillus species, even in coculture with different Candida species. We found a similar ergosterol-depleting effect with other lactobacillus strains (Lactobacillus crispatus and Lactobacillus rhamosus) on Candida albicans, Candida tropicalis, and Candida krusei. The addition of ergosterol improved C. glabrata growth in the coculture. Blocking ergosterol synthesis with fluconazole increased the susceptibility against L. fermentum, which was again mitigated by the addition of ergosterol. In accordance, a C. glabrata Δerg11 mutant, defective in ergosterol biosynthesis, was highly sensitive to L. fermentum. In conclusion, our analysis indicates an unexpected direct function of ergosterol for C. glabrata proliferation in coculture with L. fermentum. IMPORTANCE The yeast Candida glabrata, an opportunistic fungal pathogen, and the bacterium Limosilactobacillus fermentum both inhabit the human gastrointestinal and vaginal tract. Lactobacillus species, belonging to the healthy human microbiome, are thought to prevent C. glabrata infections. We investigated the antifungal effect of Limosilactobacillus fermentum on C. glabrata strains quantitively in vitro. The interaction between C. glabrata and L. fermentum evokes an upregulation of genes required for the synthesis of ergosterol, a sterol constituent of the fungal plasma membrane. We found a dramatic reduction of ergosterol in C. glabrata when it was exposed to L. fermentum. This effect extended to other Candida species and other Lactobacillus species. Furthermore, fungal growth was efficiently suppressed by a combination of L. fermentum and fluconazole, an antifungal drug which inhibits ergosterol synthesis. Thus, fungal ergosterol is a key metabolite for the suppression of C. glabrata by L. fermentum.
Collapse
Affiliation(s)
- Isabella Zangl
- University of Natural Resources and Life Sciences, Vienna, Institute of Microbial Genetics, Tulln, Austria
| | - Reinhard Beyer
- University of Natural Resources and Life Sciences, Vienna, Institute of Microbial Genetics, Tulln, Austria
| | - Arianna Gattesco
- University of Natural Resources and Life Sciences, Vienna, Institute of Microbial Genetics, Tulln, Austria
| | - Roman Labuda
- Institute of Food Safety, Food Technology and Veterinary Public Health, University of Veterinary Medicine Vienna, Vienna, Austria
- Bioactive Microbial Metabolites, University of Natural Resources and Life Sciences, Vienna (BOKU), Institute of Microbial Genetics, Tulln, Austria
| | - Ildiko-Julia Pap
- University Hospital of St. Pölten, Institute for Hygiene and Microbiology, St. Pölten, Austria
| | - Joseph Strauss
- University of Natural Resources and Life Sciences, Vienna, Institute of Microbial Genetics, Tulln, Austria
- Bioactive Microbial Metabolites, University of Natural Resources and Life Sciences, Vienna (BOKU), Institute of Microbial Genetics, Tulln, Austria
| | - Christoph Schüller
- University of Natural Resources and Life Sciences, Vienna, Institute of Microbial Genetics, Tulln, Austria
- Core Facility Bioactive Molecules: Screening and Analysis, University of Natural Resources and Life Sciences, Vienna, Austria
| |
Collapse
|
11
|
Rao KH, Paul S, Natarajan K, Ghosh S. N-acetylglucosamine kinase, Hxk1is a multifaceted metabolic enzyme in model pathogenic yeast Candida albicans. Microbiol Res 2022; 263:127146. [DOI: 10.1016/j.micres.2022.127146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 07/22/2022] [Accepted: 07/22/2022] [Indexed: 10/16/2022]
|
12
|
Evoglow-Pp1 and mCherry proteins: a dual fluorescent labeling system for lactic acid bacteria. Appl Microbiol Biotechnol 2021; 105:7367-7378. [PMID: 34536099 DOI: 10.1007/s00253-021-11537-y] [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: 05/07/2021] [Revised: 07/30/2021] [Accepted: 08/19/2021] [Indexed: 10/20/2022]
Abstract
Fluorescent proteins are widely used for cell and protein tracking. Most of these proteins show a high signal and need the presence of oxygen to emit fluorescence. Among them, the fluorescent protein mCherry stands up because of its bright signal and fast maturation. Furthermore, the anaerobic cyan-green fluorescent protein Evoglow-Pp1 allows fluorescent detection under anaerobic conditions. In this work, we modified the pNZ:TuR.aFP plasmid, which harbors the gene encoding Evoglow-Pp1 and the promoter of elongation factor Tu from Limosilactobacillus reuteri CECT925, to obtain a plasmid containing the mrfp gene encoding the monomeric mCherry (pNZ:TuR.mCherry). Moreover, both genes were cloned together (pNZ:TuR.aFP.mCherry) developing a chimeric protein; and with a stop codon between them (pNZ:TuR.aFP.STOP.mCherry) resulting in the expression of both Evoglow-Pp1 and mCherry proteins separately under the influence of the same promoter. Lactococcus lactis, Lacticaseibacillus casei, Lactiplantibacillus plantarum, Limosilactobacillus fermentum, Lacticaseibacillus rhamnosus, and L. reuteri strains were transformed with the previously mentioned plasmids, showing an excellent red (pNZ:TuR.mCherry), green (pNZ:TuR.aFP), and red combined with green (pNZ:TuR.aFP.mCherry and pNZ:TuR.aFP.STOP.mCherry) fluorescence signal. Both fluorescence emissions were stable in strains transformed with pNZ:TuR.aFP.STOP.mCherry, while differences in the red or green fluorescence emission were observed in some of the strains harboring pNZ:TuR.aFP.mCherry. Moreover, these plasmids allowed strains differentiation in a complex environment, such as fecal microbiota. Hence, we present the plasmid pNZ:TuR.aFP.STOP.mCherry as a useful tool for the labeling of lactobacilli strains, which would be functional under anoxic conditions, thanks to Evoglow-Pp1, while having the high brightness and good photostability of mCherry. KEY POINTS: • LAB transformed with pNZ:TuR.mCherry expressed the red fluorescent protein mCherry. • LAB transformed with pNZ:TuR.aFP.mCherry developed a fusion of both proteins Evoglow-Pp1 and mCherry. • LAB with pNZ:TuR.aFP.STOP.mCherry expressed both fluorescent proteins separately.
Collapse
|
13
|
The Pentose Phosphate Pathway in Yeasts-More Than a Poor Cousin of Glycolysis. Biomolecules 2021; 11:biom11050725. [PMID: 34065948 PMCID: PMC8151747 DOI: 10.3390/biom11050725] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/04/2021] [Accepted: 05/10/2021] [Indexed: 01/14/2023] Open
Abstract
The pentose phosphate pathway (PPP) is a route that can work in parallel to glycolysis in glucose degradation in most living cells. It has a unidirectional oxidative part with glucose-6-phosphate dehydrogenase as a key enzyme generating NADPH, and a non-oxidative part involving the reversible transketolase and transaldolase reactions, which interchange PPP metabolites with glycolysis. While the oxidative branch is vital to cope with oxidative stress, the non-oxidative branch provides precursors for the synthesis of nucleic, fatty and aromatic amino acids. For glucose catabolism in the baker’s yeast Saccharomyces cerevisiae, where its components were first discovered and extensively studied, the PPP plays only a minor role. In contrast, PPP and glycolysis contribute almost equally to glucose degradation in other yeasts. We here summarize the data available for the PPP enzymes focusing on S. cerevisiae and Kluyveromyces lactis, and describe the phenotypes of gene deletions and the benefits of their overproduction and modification. Reference to other yeasts and to the importance of the PPP in their biotechnological and medical applications is briefly being included. We propose future studies on the PPP in K. lactis to be of special interest for basic science and as a host for the expression of human disease genes.
Collapse
|
14
|
Chung H, Lee YH. Hypoxia: A Double-Edged Sword During Fungal Pathogenesis? Front Microbiol 2020; 11:1920. [PMID: 32903454 PMCID: PMC7434965 DOI: 10.3389/fmicb.2020.01920] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 07/21/2020] [Indexed: 12/18/2022] Open
Abstract
Molecular oxygen functions as an electron acceptor for aerobic respiration and a substrate for key metabolisms and cellular processes. Most eukaryotes develop direct or indirect oxygen sensors and reprogram transcriptional and translational metabolisms to adapt to altered oxygen availability under varying oxygen concentrations. Human fungal pathogens manipulate transcriptional levels of genes related to virulence as well as oxygen-dependent metabolisms such as ergosterol homeostasis when they are confronted with oxygen limitation (hypoxia) during infection. Oxygen states in plant tissues also vary depending on site, species, and external environment, potentially providing hypoxia to plant pathogens during infection. In this review, knowledge on the regulation of oxygen sensing and adaptive mechanisms in eukaryotes and nascent understanding of hypoxic responses in plant pathogens are summarized and discussed.
Collapse
Affiliation(s)
- Hyunjung Chung
- Department of Agricultural Biotechnology, Seoul National University, Seoul, South Korea
| | - Yong-Hwan Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul, South Korea.,Center for Fungal Genetic Resources, Plant Immunity Research Center, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea
| |
Collapse
|
15
|
Boniek D, Bonadio L, Damaceno QS, Dos Santos AFB, de Resende Stoianoff MA. Occurrence of Aspergillus niger strains on a polychrome cotton painting and their elimination by anoxic treatment. Can J Microbiol 2020; 66:586-592. [PMID: 32497439 DOI: 10.1139/cjm-2020-0173] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study aimed to isolate and identify the population of filamentous fungi colonizing a cotton painting, whose conservation status was compromised and showed signs of biodeterioration due to dirt accumulation and microbial metabolism. In addition, microbiological techniques such as cultivation-dependent approach and molecular biology were used to identify microbial populations and to eliminate their metabolic action. For this, the nondestructive anoxic atmosphere technique was used, in which the microbial metabolism was affected by the absence of oxygen. Prior to exposure to an anoxic atmosphere, only one fungal species, Aspergillus niger, was identified at 12 points sampled in the obverse and reverse of the artwork; no fungal species persisted as a result of anoxic treatment. These results showed that exposure to anoxic conditions was effective for the total elimination of isolated fungal strains as well as their spores. In conclusion, this study proved the unprecedented effectiveness of a nondestructive technique for artwork on textile colonized by black fungi species. Thus, this interdisciplinary work involving conservation, microbiology, and chemistry presents a tool to eliminate microorganisms, while maintaining the integrity of artwork and safety of the restorer, that can be applied prior to artwork restoration.
Collapse
Affiliation(s)
- Douglas Boniek
- Department of Microbiology, Institute of Biological Science, Federal University of Minas Gerais, UFMG, Av. Antônio Carlos, 6627, Belo Horizonte, CEP 31270-901, Minas Gerais, Brazil
| | - Luciana Bonadio
- Department of Fine Arts, School of Fine Arts, Federal University of Minas Gerais, UFMG, Av. Antônio Carlos, 6627, Belo Horizonte, CEP 31270-901, Minas Gerais, Brazil
| | - Quésia Souza Damaceno
- Department of Microbiology, Institute of Biological Science, Federal University of Minas Gerais, UFMG, Av. Antônio Carlos, 6627, Belo Horizonte, CEP 31270-901, Minas Gerais, Brazil
| | - Antônio Fernando Batista Dos Santos
- Faculty of Engineering and Architecture, Education and Culture Foundation of Minas Gerais, FUMEC University, Cobre Street, 200, Belo Horizonte, 30310-190, Minas Gerais, Brazil
| | - Maria Aparecida de Resende Stoianoff
- Department of Microbiology, Institute of Biological Science, Federal University of Minas Gerais, UFMG, Av. Antônio Carlos, 6627, Belo Horizonte, CEP 31270-901, Minas Gerais, Brazil
| |
Collapse
|
16
|
Chung H, Kim S, Kim KT, Hwang BG, Kim HJ, Lee SJ, Lee YH. A novel approach to investigate hypoxic microenvironment during rice colonization by Magnaporthe oryzae. Environ Microbiol 2020; 21:1151-1169. [PMID: 30773773 DOI: 10.1111/1462-2920.14563] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 02/13/2019] [Indexed: 01/22/2023]
Abstract
Because molecular oxygen functions as the final acceptor of electrons during aerobic respiration and a substrate for diverse enzymatic reactions, eukaryotes employ various mechanisms to maintain cellular homeostasis under varying oxygen concentration. Human fungal pathogens change the expression of genes involved in virulence and oxygen-required metabolisms such as ergosterol (ERG) synthesis when they encounter oxygen limitation (hypoxia) during infection. The oxygen level in plant tissues also fluctuates, potentially creating hypoxic stress to pathogens during infection. However, little is known about how in planta oxygen dynamics impact pathogenesis. In this study, we investigated oxygen dynamics in rice during infection by Magnaporthe oryzae via two approaches. First, rice leaves infected by M. oryzae were noninvasively probed using a microscopic oxygen sensor. Second, an immunofluorescence assay based on a chemical probe, pimonidazole, was used. Both methods showed that oxygen concentration in rice decreased after fungal penetration. We also functionally characterized five hypoxia-responsive genes participating in ERG biosynthesis for their role in pathogenesis. Resulting insights and tools will help study the nature of in planta oxygen dynamics in other pathosystems.
Collapse
Affiliation(s)
- Hyunjung Chung
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, South Korea
| | - Seongbeom Kim
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, South Korea
| | - Ki-Tae Kim
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, South Korea
| | - Bae-Geun Hwang
- Department of Mechanical Engineering, Center for Biofluid and Biomimic Research, Pohang University of Science and Technology, Pohang 37673, South Korea
| | - Hye-Jeong Kim
- Department of Mechanical Engineering, Center for Biofluid and Biomimic Research, Pohang University of Science and Technology, Pohang 37673, South Korea
| | - Sang-Joon Lee
- Department of Mechanical Engineering, Center for Biofluid and Biomimic Research, Pohang University of Science and Technology, Pohang 37673, South Korea
| | - Yong-Hwan Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, South Korea.,Center for Fungal Genetic Resources, Plant Immunity Research Center, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, South Korea
| |
Collapse
|
17
|
Abstract
Hypoxia is the predominant condition that the human opportunistic fungus Candida albicans encounters in the majority of the colonized niches within the host. So far, the impact of such a condition on the overall metabolism of this important human-pathogenic yeast has not been investigated. Here, we have undertaken a time-resolved metabolomics analysis to uncover the metabolic landscape of fungal cells experiencing hypoxia. Our data showed a dynamic reprogramming of many fundamental metabolic pathways, such as glycolysis, the pentose phosphate pathway, and different metabolic routes related to fungal cell wall biogenesis. The C. albicans lipidome was highly affected by oxygen depletion, with an increased level of free fatty acids and biochemical intermediates of membrane lipids, including phospholipids, lysophospholipids, sphingolipids, and mevalonate. The depletion of oxygen-dependent lipids such as ergosterol or phosphatidylcholine with longer and polyunsaturated lateral fatty acid chains was observed only at the later hypoxic time point (180 min). Transcriptomics data supported the main metabolic response to hypoxia when matched to our metabolomic profiles. The hypoxic metabolome reflected different physiological alterations of the cell wall and plasma membrane of C. albicans under an oxygen-limiting environment that were confirmed by different approaches. This study provided a framework for future in vivo investigations to examine relevant hypoxic metabolic trajectories in fungal virulence and fitness within the host.IMPORTANCE A critical aspect of cell fitness is the ability to sense and adapt to variations in oxygen levels in their local environment. Candida albicans is an opportunistic yeast that is the most prevalent human fungal pathogen. While hypoxia is the predominant condition that C. albicans encounters in most of its niches, its impact on fungal metabolism remains unexplored so far. Here, we provided a detailed landscape of the C. albicans metabolome that emphasized the importance of many metabolic routes for the adaptation of this yeast to oxygen depletion. The fungal hypoxic metabolome identified in this work provides a framework for future investigations to assess the contribution of relevant metabolic pathways in the fitness of C. albicans and other human eukaryotic pathogens with similar colonized human niches. As hypoxia is present at most of the fungal infection foci in the host, hypoxic metabolic pathways are thus an attractive target for antifungal therapy.
Collapse
|
18
|
Rastogi SK, van Wijlick L, Ror S, Lee KK, Román E, Agarwal P, Manzoor N, Gow NAR, Pla J, Ernst JF, Panwar SL. Ifu5, a WW domain-containing protein interacts with Efg1 to achieve coordination of normoxic and hypoxic functions to influence pathogenicity traits in Candida albicans. Cell Microbiol 2020; 22:e13140. [PMID: 31736226 PMCID: PMC7614792 DOI: 10.1111/cmi.13140] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 10/03/2019] [Accepted: 10/23/2019] [Indexed: 11/28/2022]
Abstract
Hypoxic adaptation pathways, essential for Candida albicans pathogenesis, are tied to its transition from a commensal to a pathogen. Herein, we identify a WW domain-containing protein, Ifu5, as a determinant of hypoxic adaptation that also impacts normoxic responses in this fungus. Ifu5 activity supports glycosylation homeostasis via the Cek1 mitogen-activated protein kinase-dependent up-regulation of PMT1, under normoxia. Transcriptome analysis of ifu5Δ/Δ under normoxia shows a significant up-regulation of the hypoxic regulator EFG1 and EFG1-dependent genes. We demonstrate physical interaction between Ifu5 by virtue of its WW domain and Efg1 that represses EFG1 expression under normoxia. This interaction is lost under hypoxic growth conditions, relieving EFG1 repression. Hypoxic adaptation processes such as filamentation and biofilm formation are affected in ifu5Δ/Δ cells revealing the role of Ifu5 in hypoxic signalling and modulating pathogenicity traits of C. albicans under varied oxygen conditions. Additionally, the WW domain of Ifu5 facilitates its role in hypoxic adaptation, revealing the importance of this domain in providing a platform to integrate various cellular processes. These data forge a relationship between Efg1 and Ifu5 that fosters the role of Ifu5 in hypoxic adaptation thus illuminating novel strategies to undermine the growth of C. albicans.
Collapse
Affiliation(s)
- Sumit K Rastogi
- Yeast Molecular Genetics Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
- Medical Mycology Laboratory, Department of Biosciences, Jamia Millia Islamia University, New Delhi, India
| | - Lasse van Wijlick
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Shivani Ror
- Yeast Molecular Genetics Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Keunsook K Lee
- The Aberdeen Fungal Group, MRC Centre for Medical Mycology, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Elvira Román
- Departamento de Microbiología y Parasitología-IRYCIS, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain
| | - Pranjali Agarwal
- Yeast Molecular Genetics Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Nikhat Manzoor
- Medical Mycology Laboratory, Department of Biosciences, Jamia Millia Islamia University, New Delhi, India
| | - Neil A R Gow
- The Aberdeen Fungal Group, MRC Centre for Medical Mycology, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Jesús Pla
- Departamento de Microbiología y Parasitología-IRYCIS, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain
| | - Joachim F Ernst
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Sneh L Panwar
- Yeast Molecular Genetics Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| |
Collapse
|
19
|
He Z, Zhao X, Gao Y, Keyhani NO, Wang H, Deng J, Lu Z, Kan Y, Luo Z, Zhang Y. The fungal mitochondrial membrane protein, BbOhmm, antagonistically controls hypoxia tolerance. Environ Microbiol 2020; 22:2514-2535. [DOI: 10.1111/1462-2920.14910] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 12/23/2019] [Accepted: 12/29/2019] [Indexed: 01/15/2023]
Affiliation(s)
- Zhangjiang He
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural SciencesSouthwest University Chongqing 400715 China
- Biochemical Engineering Center of Guizhou ProvinceGuizhou University Guiyang 50025 China
| | - Xin Zhao
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural SciencesSouthwest University Chongqing 400715 China
| | - Yifei Gao
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural SciencesSouthwest University Chongqing 400715 China
| | - Nemat O. Keyhani
- Department of Microbiology and Cell ScienceUniversity of Florida Gainesville FL 32611 USA
| | - Huifang Wang
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural SciencesSouthwest University Chongqing 400715 China
| | - Juan Deng
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural SciencesSouthwest University Chongqing 400715 China
| | - Zhuoyue Lu
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural SciencesSouthwest University Chongqing 400715 China
| | - Yanze Kan
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural SciencesSouthwest University Chongqing 400715 China
| | - Zhibing Luo
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural SciencesSouthwest University Chongqing 400715 China
| | - Yongjun Zhang
- Biotechnology Research Center, State Cultivation Base of Crop Stress Biology for Southern Mountainous Land of Southwest University, Academy of Agricultural SciencesSouthwest University Chongqing 400715 China
| |
Collapse
|
20
|
Brown AJP, Larcombe DE, Pradhan A. Thoughts on the evolution of Core Environmental Responses in yeasts. Fungal Biol 2020; 124:475-481. [PMID: 32389310 PMCID: PMC7232023 DOI: 10.1016/j.funbio.2020.01.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 01/07/2020] [Accepted: 01/09/2020] [Indexed: 12/18/2022]
Abstract
The model yeasts, Saccharomyces cerevisiae and Schizosaccharomyces pombe, display Core Environmental Responses (CERs) that include the induction of a core set of stress genes in response to diverse environmental stresses. CERs underlie the phenomenon of stress cross-protection, whereby exposure to one type of stress can provide protection against subsequent exposure to a second type of stress. CERs have probably arisen through the accumulation, over evolutionary time, of protective anticipatory responses (“adaptive prediction”). CERs have been observed in other evolutionarily divergent fungi but, interestingly, not in the pathogenic yeast, Candida albicans. We argue that this is because we have not looked in the right place. In response to specific host inputs, C. albicans does activate anticipatory responses that protect it against impending attack from the immune system. Therefore, we suggest that C. albicans has evolved a CER that reflects the environmental challenges it faces in host niches. We review Core Environmental Responses (CERs) in domesticated and pathogenic yeasts. CERs probably evolved through the accumulation of protective anticipatory responses. Evolutionarily diverse yeasts display CERs, but the pathogen, Candida albicans, does not. C. albicans has evolved an alternative CER that protects against immune clearance. This has implications for the investigation of CERs in other fungi.
Collapse
Affiliation(s)
- Alistair J P Brown
- MRC Centre for Medical Mycology, University of Exeter, Department of Biosciences, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
| | - Daniel E Larcombe
- MRC Centre for Medical Mycology, University of Exeter, Department of Biosciences, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
| | - Arnab Pradhan
- MRC Centre for Medical Mycology, University of Exeter, Department of Biosciences, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
| |
Collapse
|
21
|
Burgain A, Pic É, Markey L, Tebbji F, Kumamoto CA, Sellam A. A novel genetic circuitry governing hypoxic metabolic flexibility, commensalism and virulence in the fungal pathogen Candida albicans. PLoS Pathog 2019; 15:e1007823. [PMID: 31809527 PMCID: PMC6919631 DOI: 10.1371/journal.ppat.1007823] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 12/18/2019] [Accepted: 10/18/2019] [Indexed: 01/04/2023] Open
Abstract
Inside the human host, the pathogenic yeast Candida albicans colonizes predominantly oxygen-poor niches such as the gastrointestinal and vaginal tracts, but also oxygen-rich environments such as cutaneous epithelial cells and oral mucosa. This suppleness requires an effective mechanism to reversibly reprogram the primary metabolism in response to oxygen variation. Here, we have uncovered that Snf5, a subunit of SWI/SNF chromatin remodeling complex, is a major transcriptional regulator that links oxygen status to the metabolic capacity of C. albicans. Snf5 and other subunits of SWI/SNF complex were required to activate genes of carbon utilization and other carbohydrates related process specifically under hypoxia. snf5 mutant exhibited an altered metabolome reflecting that SWI/SNF plays an essential role in maintaining metabolic homeostasis and carbon flux in C. albicans under hypoxia. Snf5 was necessary to activate the transcriptional program linked to both commensal and invasive growth. Accordingly, snf5 was unable to maintain its growth in the stomach, the cecum and the colon of mice. snf5 was also avirulent as it was unable to invade Galleria larvae or to cause damage to human enterocytes and murine macrophages. Among candidates of signaling pathways in which Snf5 might operate, phenotypic analysis revealed that mutants of Ras1-cAMP-PKA pathway, as well as mutants of Yak1 and Yck2 kinases exhibited a similar carbon flexibility phenotype as did snf5 under hypoxia. Genetic interaction analysis indicated that the adenylate cyclase Cyr1, a key component of the Ras1-cAMP pathway interacted genetically with Snf5. Our study yielded new insight into the oxygen-sensitive regulatory circuit that control metabolic flexibility, stress, commensalism and virulence in C. albicans. A critical aspect of eukaryotic cell fitness is the ability to sense and adapt to variations in oxygen level in their local environment. Hypoxia leads to a substantial remodeling of cell metabolism and energy homeostasis, and thus, organisms must develop an effective regulatory mechanism to cope with oxygen depletion. Candida albicans is an opportunistic yeast that is the most prevalent human fungal pathogens. This yeast colonizes diverse niches inside the human host with contrasting carbon sources and oxygen concentrations. While hypoxia is the predominant condition that C. albicans encounters inside most of the niches, the impact of this condition on metabolic flexibility, a major determinant of fungal virulence, was completely unexplored. Here, we uncovered that the chromatin remodelling complex SWI/SNF is a master regulator of the circuit that links oxygen status to a broad spectrum of carbon utilization routes. Snf5 was essential for the maintenance of C. albicans as a commensal and also for the expression of its virulence. The oxygen-sensitive regulators identified in this work provide a framework to comprehensively understand the virulence of human fungal pathogens and represent a therapeutic value to fight fungal infections.
Collapse
Affiliation(s)
- Anaïs Burgain
- CHU de Québec Research Center (CHUQ), Université Laval, Quebec City, Quebec, Canada
- Department of Microbiology, Infectious Diseases and Immunology, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
| | - Émilie Pic
- CHU de Québec Research Center (CHUQ), Université Laval, Quebec City, Quebec, Canada
| | - Laura Markey
- Program in Molecular Microbiology, Tufts University, Boston, Massachusetts, United States of America
- Department of Molecular Biology and Microbiology, Tufts University, Boston, Massachusetts, United States of America
| | - Faiza Tebbji
- CHU de Québec Research Center (CHUQ), Université Laval, Quebec City, Quebec, Canada
| | - Carol A. Kumamoto
- Department of Molecular Biology and Microbiology, Tufts University, Boston, Massachusetts, United States of America
| | - Adnane Sellam
- CHU de Québec Research Center (CHUQ), Université Laval, Quebec City, Quebec, Canada
- Department of Microbiology, Infectious Diseases and Immunology, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
- Big Data Research Centre (BDRC-UL), Université Laval, Faculty of Sciences and Engineering, Quebec City, Quebec, Canada
- * E-mail:
| |
Collapse
|
22
|
|
23
|
Suparmin A, Kato T, Takemoto H, Park EY. Metabolic comparison of aerial and submerged mycelia formed in the liquid surface culture of Cordyceps militaris. Microbiologyopen 2019; 8:e00836. [PMID: 30924317 PMCID: PMC6741141 DOI: 10.1002/mbo3.836] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 02/23/2019] [Accepted: 02/26/2019] [Indexed: 12/11/2022] Open
Abstract
An entomopathogenic fungus, Cordyceps sp. has been known to produce cordycepin which is a purine nucleoside antimetabolite and antibiotic with potential anticancer, antioxidant and anti-inflammatory activities. Interestingly, Cordyceps militaris produces significantly higher amount in a liquid surface culture than in a submerged culture. The liquid surface culture consists of mycelia growing into the air (aerial mycelia) and mycelia growing toward the bottom into the medium (submerged mycelia). In this study, to clarify roles of aerial and submerged mycelia of C. militaris in the cordycepin production the difference in metabolism between these mycelia was investigated. From transcriptomic analyses of the aerial and submerged mycelia at the culture of 5, 12 and 19 days, the metabolism of the submerged mycelia switched from the oxidative phosphorylation to the fermentation pathway. This activated the pentose phosphate pathway to provide building block materials for the nucleotide biosynthetic pathway. Under hypoxic conditions, the 5-aminolevulinic acid synthase (CCM_01504), delta-aminolevulinic acid dehydratase (CCM_00935), coproporphyrinogen III oxidase (CCM_07483) and cytochrome c oxidase 15 (CCM_05057) genes of heme biosynthesis were significantly upregulated. In addition, the liquid surface culture revealed that metabolite coproporhyrinogen III and glycine, the product and precursor of heme, were increased at 12th day and decreased at 19th day, respectively. These results indicate that the submerged mycelia induce the activation of iron acquisition, the ergosterol biosynthetic pathway, and the iron cluster genes of cordycepin biosynthesis in a hypoxic condition. Even though, the expression of the cluster genes of cordycepin biosynthesis was not significantly different in both types of mycelia.
Collapse
Affiliation(s)
- Ahmad Suparmin
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, Suruga-ku, Shizuoka, Japan
| | - Tatsuya Kato
- Laboratory of Biotechnology, Green Chemistry Research Division, Research Institute of Green Science and Technology, Shizuoka University, Suruga-ku, Shizuoka, Japan
| | - Hiroyuki Takemoto
- Instrumental Research Support Office, Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, Suruga-ku, Shizuoka, Japan
| | - Enoch Y Park
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, Suruga-ku, Shizuoka, Japan.,Laboratory of Biotechnology, Green Chemistry Research Division, Research Institute of Green Science and Technology, Shizuoka University, Suruga-ku, Shizuoka, Japan
| |
Collapse
|
24
|
Hypoxia Promotes Immune Evasion by Triggering β-Glucan Masking on the Candida albicans Cell Surface via Mitochondrial and cAMP-Protein Kinase A Signaling. mBio 2018; 9:mBio.01318-18. [PMID: 30401773 PMCID: PMC6222127 DOI: 10.1128/mbio.01318-18] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Organisms must adapt to changes in oxygen tension if they are to exploit the energetic benefits of reducing oxygen while minimizing the potentially damaging effects of oxidation. Consequently, organisms in all eukaryotic kingdoms display robust adaptation to hypoxia (low oxygen levels). This is particularly important for fungal pathogens that colonize hypoxic niches in the host. We show that adaptation to hypoxia in the major fungal pathogen of humans Candida albicans includes changes in cell wall structure and reduced exposure, at the cell surface, of β-glucan, a key pathogen-associated molecular pattern (PAMP). This leads to reduced phagocytosis by murine bone marrow-derived macrophages and decreased production of IL-10, RANTES, and TNF-α by peripheral blood mononuclear cells, suggesting that hypoxia-induced β-glucan masking has a significant effect upon C. albicans-host interactions. We show that hypoxia-induced β-glucan masking is dependent upon both mitochondrial and cAMP-protein kinase A (PKA) signaling. The decrease in β-glucan exposure is blocked by mutations that affect mitochondrial functionality (goa1Δ and upc2Δ) or that decrease production of hydrogen peroxide in the inner membrane space (sod1Δ). Furthermore, β-glucan masking is enhanced by mutations that elevate mitochondrial reactive oxygen species (aox1Δ). The β-glucan masking defects displayed by goa1Δ and upc2Δ cells are suppressed by exogenous dibutyryl-cAMP. Also, mutations that inactivate cAMP synthesis (cyr1Δ) or PKA (tpk1Δ tpk2Δ) block the masking phenotype. Our data suggest that C. albicans responds to hypoxic niches by inducing β-glucan masking via a mitochondrial cAMP-PKA signaling pathway, thereby modulating local immune responses and promoting fungal colonization.IMPORTANCE Animal, plant, and fungal cells occupy environments that impose changes in oxygen tension. Consequently, many species have evolved mechanisms that permit robust adaptation to these changes. The fungal pathogen Candida albicans can colonize hypoxic (low oxygen) niches in its human host, such as the lower gastrointestinal tract and inflamed tissues, but to colonize its host, the fungus must also evade local immune defenses. We reveal, for the first time, a defined link between hypoxic adaptation and immune evasion in C. albicans As this pathogen adapts to hypoxia, it undergoes changes in cell wall structure that include masking of β-glucan at its cell surface, and it becomes better able to evade phagocytosis by innate immune cells. We also define the signaling mechanisms that mediate hypoxia-induced β-glucan masking, showing that they are dependent on mitochondrial signaling and the cAMP-protein kinase pathway. Therefore, hypoxia appears to trigger immune evasion in this fungal pathogen.
Collapse
|
25
|
Growth and protease secretion of Scedosporium aurantiacum under conditions of hypoxia. Microbiol Res 2018; 216:23-29. [PMID: 30269853 DOI: 10.1016/j.micres.2018.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 08/02/2018] [Accepted: 08/03/2018] [Indexed: 12/19/2022]
Abstract
One of the micro-environmental stresses that fungal pathogens, such as Scedosporium aurantiacum, colonising human lungs encounter in vivo is hypoxia, or deficiency of oxygen. In this work, we studied the impacts of a hypoxic micro-environment (oxygen levels ≤1%) on the growth of a clinical S. aurantiacum isolate (WM 06.482; CBS 136046) and an environmental strain (S. aurantiacum WM 10.136; CBS 136049) on mucin-containing synthetic cystic fibrosis sputum medium. Additionally, profiles of secreted proteases were compared between the two isolates and protease activity was assessed using class-specific substrates and inhibitors. Overall, both isolates grew slower and produced less biomass under hypoxia compared to normoxic conditions. The pH of the medium decreased to 4.0 over the cultivation time, indicating that S. aurantiacum released acidic compounds into the medium. Accordingly, secreted proteases of the two isolates were dominated by acidic proteases, including aspartic and cysteine proteases, with optimal protease activity at pH 4.0 and 6.0 respectively. The clinical isolate produced higher aspartic and cysteine protease activities. Conversely, all serine proteases, including elastase-like, trypsin-like, chymotrypsin-like and subtilisin-like proteases had higher activities in the environmental isolate. Sequence similarities to 13 secreted proteases were identified by mass spectrometry (MS) by searching against other fungal proteases in the NCBI database. Results from MS analysis were consistent with those from activity assays. The clinical highly-virulent, and environmental low-virulence S. aurantiacum isolates responded differently to hypoxia in terms of the type of proteases secreted, which may reflect their different virulence properties.
Collapse
|
26
|
Oliveira AS, Rangel DEN. Transient anoxia during Metarhizium robertsii growth increases conidial virulence to Tenebrio molitor. J Invertebr Pathol 2018. [PMID: 29530642 DOI: 10.1016/j.jip.2018.03.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Little is known about the phenotypic effects of hypoxia and transient anoxia on the virulence of an entomopathogenic fungus. Conidia of Metarhizium robertsii were produced on: (1) potato dextrose agar medium (PDA) under normoxia; (2) PDA medium under continuous hypoxia; (3) PDA medium under transient anoxia; and (4) minimal medium with lactose (MML) under normoxia. Conidia produced under transient anoxia and produced on MML were the most virulent to Tenebrio molitor. Conidia produced under normoxia and hypoxia were the least virulent. Conidial production and germination speed of conidia produced under normoxia, hypoxia, and transient anoxia were similar; however, MML produced less conidia, but germinated faster than any other treatments.
Collapse
Affiliation(s)
- Ariel S Oliveira
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO 74605-050, Brazil
| | - Drauzio E N Rangel
- Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, GO 74605-050, Brazil; Instituto de Ciências e Tecnologia, Universidade Brasil, São Paulo, SP 08230-030, Brazil.
| |
Collapse
|
27
|
Parente-Rocha JA, Tomazett MV, Pigosso LL, Bailão AM, Ferreira de Souza A, Paccez JD, Baeza LC, Pereira M, Silva Bailão MG, Borges CL, Maria de Almeida Soares C. In vitro, ex vivo and in vivo models: A comparative analysis of Paracoccidioides spp. proteomic studies. Fungal Biol 2017; 122:505-513. [PMID: 29801795 DOI: 10.1016/j.funbio.2017.10.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 10/20/2017] [Accepted: 10/22/2017] [Indexed: 01/12/2023]
Abstract
Members of the Paracoccidioides complex are human pathogens that infect different anatomic sites in the host. The ability of Paracoccidioides spp. to infect host niches is putatively supported by a wide range of virulence factors, as well as fitness attributes that may comprise the transition from mycelia/conidia to yeast cells, response to deprivation of micronutrients in the host, expression of adhesins on the cell surface, response to oxidative and nitrosative stresses, as well as the secretion of hydrolytic enzymes in the host tissue. Our understanding of how those molecules can contribute to the infection establishment has been increasing significantly, through the utilization of several models, including in vitro, ex vivo and in vivo infection in animal models. In this review we present an update of our understanding on the strategies used by the pathogen to establish infection. Our results were obtained through a comparative proteomic analysis of Paracoccidioides spp. in models of infection.
Collapse
Affiliation(s)
- Juliana Alves Parente-Rocha
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil.
| | - Mariana Vieira Tomazett
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil.
| | - Laurine Lacerda Pigosso
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil.
| | - Alexandre Melo Bailão
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil.
| | - Aparecido Ferreira de Souza
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil.
| | - Juliano Domiraci Paccez
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil.
| | - Lilian Cristiane Baeza
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil.
| | - Maristela Pereira
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil.
| | - Mirelle Garcia Silva Bailão
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil; Unidade Acadêmica Especial Ciências da Saúde, Universidade Federal de Goiás, Jataí, Goiás, Brazil.
| | - Clayton Luiz Borges
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil.
| | - Célia Maria de Almeida Soares
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Laboratório de Biologia Molecular, Campus Samambaia s/n ICB2, Sala 206, Goiânia, Goiás, Brazil.
| |
Collapse
|
28
|
DuBois JC, Smulian AG. Sterol Regulatory Element Binding Protein (Srb1) Is Required for Hypoxic Adaptation and Virulence in the Dimorphic Fungus Histoplasma capsulatum. PLoS One 2016; 11:e0163849. [PMID: 27711233 PMCID: PMC5053422 DOI: 10.1371/journal.pone.0163849] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Accepted: 09/08/2016] [Indexed: 01/12/2023] Open
Abstract
The Histoplasma capsulatum sterol regulatory element binding protein (SREBP), Srb1 is a member of the basic helix-loop-helix (bHLH), leucine zipper DNA binding protein family of transcription factors that possess a unique tyrosine (Y) residue instead of an arginine (R) residue in the bHLH region. We have determined that Srb1 message levels increase in a time dependent manner during growth under oxygen deprivation (hypoxia). To further understand the role of Srb1 during infection and hypoxia, we silenced the gene encoding Srb1 using RNA interference (RNAi); characterized the resulting phenotype, determined its response to hypoxia, and its ability to cause disease within an infected host. Silencing of Srb1 resulted in a strain of H. capsulatum that is incapable of surviving in vitro hypoxia. We found that without complete Srb1 expression, H. capsulatum is killed by murine macrophages and avirulent in mice given a lethal dose of yeasts. Additionally, silencing Srb1 inhibited the hypoxic upregulation of other known H. capsulatum hypoxia-responsive genes (HRG), and genes that encode ergosterol biosynthetic enzymes. Consistent with these regulatory functions, Srb1 silenced H. capsulatum cells were hypersensitive to the antifungal azole drug itraconazole. These data support the theory that the H. capsulatum SREBP is critical for hypoxic adaptation and is required for H. capsulatum virulence.
Collapse
Affiliation(s)
- Juwen C. DuBois
- Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
- Cincinnati VA Medical Center, Cincinnati, Ohio, United States of America
| | - A. George Smulian
- Cincinnati VA Medical Center, Cincinnati, Ohio, United States of America
- Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
- * E-mail:
| |
Collapse
|
29
|
Zou X, Pan T, Chen L, Tian Y, Zhang W. Luminescence materials for pH and oxygen sensing in microbial cells - structures, optical properties, and biological applications. Crit Rev Biotechnol 2016; 37:723-738. [PMID: 27627832 DOI: 10.1080/07388551.2016.1223011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Luminescence including fluorescence and phosphorescence sensors have been demonstrated to be important for studying cell metabolism, and diagnosing diseases and cancer. Various design principles have been employed for the development of sensors in different formats, such as organic molecules, polymers, polymeric hydrogels, and nanoparticles. The integration of the sensing with fluorescence imaging provides valuable tools for biomedical research and applications at not only bulk-cell level but also at single-cell level. In this article, we critically reviewed recent progresses on pH, oxygen, and dual pH and oxygen sensors specifically for their application in microbial cells. In addition, we focused not only on sensor materials with different chemical structures, but also on design and applications of sensors for better understanding cellular metabolism of microbial cells. Finally, we also provided an outlook for future materials design and key challenges in reaching broad applications in microbial cells.
Collapse
Affiliation(s)
- Xianshao Zou
- a Department of Materials Science and Engineering , South University of Science and Technology of China , Shenzhen , Guangdong , P.R. China
| | - Tingting Pan
- a Department of Materials Science and Engineering , South University of Science and Technology of China , Shenzhen , Guangdong , P.R. China
| | - Lei Chen
- b Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology , Tianjin University , Tianjin , P.R. China.,c Key Laboratory of Systems Bioengineering, Ministry of Education of China , Tianjin , P.R. China.,d SynBio Platform, Collaborative Innovation Center of Chemical Science and Engineering , Tianjin , P.R. China
| | - Yanqing Tian
- a Department of Materials Science and Engineering , South University of Science and Technology of China , Shenzhen , Guangdong , P.R. China
| | - Weiwen Zhang
- b Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology , Tianjin University , Tianjin , P.R. China.,c Key Laboratory of Systems Bioengineering, Ministry of Education of China , Tianjin , P.R. China.,d SynBio Platform, Collaborative Innovation Center of Chemical Science and Engineering , Tianjin , P.R. China
| |
Collapse
|
30
|
Landete JM, Medina M, Arqués JL. Fluorescent reporter systems for tracking probiotic lactic acid bacteria and bifidobacteria. World J Microbiol Biotechnol 2016; 32:119. [PMID: 27263014 DOI: 10.1007/s11274-016-2077-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 04/27/2016] [Indexed: 12/19/2022]
Abstract
In the last two decades, there has been increasing evidence supporting the role of the intestinal microbiota in health and disease, as well as the use of probiotics to modulate its activity and composition. Probiotic bacteria selected for commercial use in foods, mostly lactic acid bacteria and bifidobacteria, must survive in sufficient numbers during the manufacturing process, storage, and passage through the gastro-intestinal tract. They have several modes of action and it is crucial to unravel the mechanisms underlying their postulated beneficial effects. To track their survival and persistence, and to analyse their interaction with the gastro-intestinal epithelia it is essential to discriminate probiotic strains from endogenous microbiota. Fluorescent reporter proteins are relevant tools that can be exploited as a non-invasive marker system for in vivo real-time imaging in complex ecosystems as well as in vitro fluorescence labelling. Oxygen is required for many of these reporter proteins to fluoresce, which is a major drawback in anoxic environments. However, some new fluorescent proteins are able to overcome the potential problems caused by oxygen limitations. The current available approaches and the benefits/disadvantages of using reporter vectors containing fluorescent proteins for labelling of bacterial probiotic species commonly used in food are addressed.
Collapse
Affiliation(s)
- José M Landete
- Dpto. de Tecnología de Alimentos, INIA, Carretera de La Coruña Km 7, 28040, Madrid, Spain
| | - Margarita Medina
- Dpto. de Tecnología de Alimentos, INIA, Carretera de La Coruña Km 7, 28040, Madrid, Spain
| | - Juan L Arqués
- Dpto. de Tecnología de Alimentos, INIA, Carretera de La Coruña Km 7, 28040, Madrid, Spain.
| |
Collapse
|
31
|
Eichhof I, Ernst JF. Oxygen-independent FbFP: Fluorescent sentinel and oxygen sensor component in Saccharomyces cerevisiae and Candida albicans. Fungal Genet Biol 2016; 92:14-25. [PMID: 27126475 DOI: 10.1016/j.fgb.2016.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 04/22/2016] [Accepted: 04/23/2016] [Indexed: 02/06/2023]
Abstract
FMN-binding fluorescent proteins (FbFPs) outperform GFP and its derivatives because of their oxygen-independence, small size and rapid maturation. FbFPs have been used successfully as reliable reporters of gene expression in the cytoplasm of pro- and eukaryotes. Here we extend previous findings on the codon-adapted CaFbFP variant, which functions in the apathogenic yeast Saccharomyces cerevisiae and the human fungal pathogen Candida albicans. In both fungal species, CaFbFP could be targeted to the nucleus and the cell wall by endogenous signals (H2B-/Aga2-fusions) demonstrating its use as a fluorescent beacon in these relevant cellular locations. Transformants of both fungal species producing a CaFbFP-YFP fusion (YFOS) showed variable energy transfer from CaFbFP to YFP (FRET) that depended in its extent on external O2 concentrations. Applications as fluorescent sentinel and oxygen biosensor expand the FbFP toolbox to study oxygen-independent cellular processes under hypoxia.
Collapse
Affiliation(s)
- Isabel Eichhof
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - Joachim F Ernst
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany.
| |
Collapse
|
32
|
Cassona CP, Pereira F, Serrano M, Henriques AO. A Fluorescent Reporter for Single Cell Analysis of Gene Expression in Clostridium difficile. Methods Mol Biol 2016; 1476:69-90. [PMID: 27507334 DOI: 10.1007/978-1-4939-6361-4_6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Genetically identical cells growing under homogeneous growth conditions often display cell-cell variation in gene expression. This variation stems from noise in gene expression and can be adaptive allowing for division of labor and bet-hedging strategies. In particular, for bacterial pathogens, the expression of phenotypes related to virulence can show cell-cell variation. Therefore, understanding virulence-related gene expression requires knowledge of gene expression patterns at the single cell level. We describe protocols for the use of fluorescence reporters for single cell analysis of gene expression in the human enteric pathogen Clostridium difficile, a strict anaerobe. The reporters are based on modified versions of the human DNA repair enzyme O ( 6)-alkylguanine-DNA alkyltransferase, called SNAP-tag and CLIP-tag. SNAP becomes covalently labeled upon reaction with O ( 6)-benzylguanine conjugated to a fluorophore, whereas CLIP is labeled by O ( 6)-benzylcytosine conjugates. SNAP and CLIP labeling is orthogonal allowing for dual labeling in the same cells. SNAP and CLIP cassettes optimized for C. difficile can be used for quantitative studies of gene expression at the single cell level. Both the SNAP and CLIP reporters can also be used for studies of protein subcellular localization in C. difficile.
Collapse
Affiliation(s)
- Carolina Piçarra Cassona
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República, Estação Agronómica Nacional, 2780-157, Oeiras, Portugal
| | - Fátima Pereira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República, Estação Agronómica Nacional, 2780-157, Oeiras, Portugal
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, University of Vienna, Althanstr. 14, 1090, Vienna, Austria
| | - Mónica Serrano
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República, Estação Agronómica Nacional, 2780-157, Oeiras, Portugal
| | - Adriano O Henriques
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Avenida da República, Estação Agronómica Nacional, 2780-157, Oeiras, Portugal.
| |
Collapse
|
33
|
Lima PDS, Chung D, Bailão AM, Cramer RA, Soares CMDA. Characterization of the Paracoccidioides Hypoxia Response Reveals New Insights into Pathogenesis Mechanisms of This Important Human Pathogenic Fungus. PLoS Negl Trop Dis 2015; 9:e0004282. [PMID: 26659387 PMCID: PMC4686304 DOI: 10.1371/journal.pntd.0004282] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 11/16/2015] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Hypoxic microenvironments are generated during fungal infection. It has been described that to survive in the human host, fungi must also tolerate and overcome in vivo microenvironmental stress conditions including low oxygen tension; however nothing is known how Paracoccidioides species respond to hypoxia. The genus Paracoccidioides comprises human thermal dimorphic fungi and are causative agents of paracoccidioidomycosis (PCM), an important mycosis in Latin America. METHODOLOGY/PRINCIPAL FINDINGS In this work, a detailed hypoxia characterization was performed in Paracoccidioides. Using NanoUPLC-MSE proteomic approach, we obtained a total of 288 proteins differentially regulated in 12 and 24 h of hypoxia, providing a global view of metabolic changes during this stress. In addition, a functional characterization of the homologue to the most important molecule involved in hypoxia responses in other fungi, the SREBP (sterol regulatory element binding protein) was performed. We observed that Paracoccidioides species have a functional homologue of SREBP, named here as SrbA, detected by using a heterologous genetic approach in the srbA null mutant in Aspergillus fumigatus. Paracoccidioides srbA (PbsrbA), in addition to involvement in hypoxia, is probable involved in iron adaptation and azole drug resistance responses. CONCLUSIONS/SIGNIFICANCE In this study, the hypoxia was characterized in Paracoccidioides. The first results can be important for a better understanding of the fungal adaptation to the host and improve the arsenal of molecules for the development of alternative treatment options in future, since molecules related to fungal adaptation to low oxygen levels are important to virulence and pathogenesis in human pathogenic fungi.
Collapse
Affiliation(s)
- Patrícia de Sousa Lima
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Dawoon Chung
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Alexandre Melo Bailão
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Robert A. Cramer
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, United States of America
| | - Célia Maria de Almeida Soares
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
- * E-mail:
| |
Collapse
|
34
|
DuBois JC, Pasula R, Dade JE, Smulian AG. Yeast Transcriptome and In Vivo Hypoxia Detection Reveals Histoplasma capsulatum Response to Low Oxygen Tension. Med Mycol 2015; 54:40-58. [PMID: 26483436 DOI: 10.1093/mmy/myv073] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Accepted: 07/13/2015] [Indexed: 12/24/2022] Open
Abstract
Although there is growing understanding of the microenvironmental conditions fungal pathogens encounter as they colonize their host, nothing is known about Histoplasma capsulatum's response to hypoxia. Here we characterized hypoxia during murine histoplasmosis using an in vivo hypoxia detection agent, Hypoxyprobe-2 (HP-2); and analyzed H. capsulatum's transcriptional profile in response to in vitro hypoxia. Immunohistopathology and flow cytometry analyses revealed distinct regions of hypoxia during infection. Granuloma cells, enriched with macrophages and T-cells isolated from infected livers were 66-76% positive for HP-2, of which, 95% of macrophages and 55% of T-cells were hypoxic. Although inhibited, H. capsulatum was able to survive under in vitro hypoxic conditions (<1% O2), and restored growth when replaced in normoxia. Next-generation sequencing (RNA-seq) analysis after 24 hours of hypoxia demonstrated a significant increase in NIT50 (swirm domain DNA binding protein), a predicted ABC transporter (ABC), NADPH oxidoreductase (NADP/FAD), and guanine nucleotide exchange factor (RSP/GEF); and other genes with no known designated function. Computational transcription factor binding site analysis predicted human sterol regulatory element binding protein (SREBP) binding sites upstream of NIT50, ABC, NADP/FAD and RSP/GEF. Hypoxia resulted in a time-dependent increase in the H. capsulatum homolog of SREBP, here named Srb1. Srb1 peaked at 8 hours and returned to basal levels by 24 hours. Our findings demonstrate that H. capsulatum encounters and survives severe hypoxia during infection. Additionally, the hypoxic response may be regulated at the level of transcription, and these studies contribute to the understanding of hypoxic regulation and adaptation in H. capsulatum.
Collapse
Affiliation(s)
- Juwen C DuBois
- Department of Pathology and Laboratory Medicine
- Cincinnati VA Medical Center, Cincinnati Ohio
| | - Rajamouli Pasula
- Department of Internal Medicine, University of Cincinnati, Cincinnati Ohio
- Cincinnati VA Medical Center, Cincinnati Ohio
| | - Jessica E Dade
- Department of Internal Medicine, University of Cincinnati, Cincinnati Ohio
- Cincinnati VA Medical Center, Cincinnati Ohio
| | - A George Smulian
- Department of Internal Medicine, University of Cincinnati, Cincinnati Ohio
- Cincinnati VA Medical Center, Cincinnati Ohio
| |
Collapse
|
35
|
Choi J, Chung H, Lee GW, Koh SK, Chae SK, Lee YH. Genome-Wide Analysis of Hypoxia-Responsive Genes in the Rice Blast Fungus, Magnaporthe oryzae. PLoS One 2015; 10:e0134939. [PMID: 26241858 PMCID: PMC4524601 DOI: 10.1371/journal.pone.0134939] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 07/16/2015] [Indexed: 01/09/2023] Open
Abstract
Rice blast fungus, Magnaporthe oryzae, is the most destructive pathogen in the rice-growing area. This fungus has a biotrophic phase early in infection and later switches to a necrotrophic lifestyle. During the biotrophic phase, the fungus competes with its host for nutrients and oxygen. Continuous uptake of oxygen is essential for successful establishment of blast disease of this pathogen. Here, we report transcriptional responses of the fungus to oxygen limitation. Transcriptome analysis using RNA-Seq identified that 1,047 genes were up-regulated in response to hypoxia. Those genes are involved in mycelial development, sterol biosynthesis, and metal ion transport based on hierarchical GO terms, and are well-conserved among three fungal species. In addition, null mutants of two hypoxia-responsive genes were generated and their roles in fungal development and pathogenicity tested. The mutant for the sterol regulatory element-binding protein gene, MoSRE1, exhibited increased sensitivity to a hypoxia-mimicking agent, increased conidiation, and delayed invasive growth within host cells, which is suggestive of important roles in fungal development. However, such defects did not cause any significant decrease in disease severity. The other null mutant, for the alcohol dehydrogenase gene MoADH1, showed no defect in the hypoxia-mimicking condition (using cobalt chloride) and fungal development. Taken together, this comprehensive transcriptional profiling in response to a hypoxic condition with experimental validations would provide new insights into fungal development and pathogenicity in plant pathogenic fungi.
Collapse
Affiliation(s)
- Jaehyuk Choi
- Division of Life Sciences, College of Life Sciences and Bioengineering, Incheon National University, Incheon 406–772, Korea
| | - Hyunjung Chung
- Department of Agricultural Biotechnology, Seoul National University, Seoul 151–921, Korea
| | - Gir-Won Lee
- Fungal Bioinformatics Laboratory, Seoul National University, Seoul 151–921, Korea
| | - Sun-Ki Koh
- Department of Biochemistry, Paichai University, Daejeon 302–735, Korea
| | - Suhn-Kee Chae
- Department of Biochemistry, Paichai University, Daejeon 302–735, Korea
| | - Yong-Hwan Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul 151–921, Korea
- Fungal Bioinformatics Laboratory, Seoul National University, Seoul 151–921, Korea
- Center for Fungal Pathogenesis, Seoul National University, Seoul 151–921, Korea
- Center for Fungal Genetic Resources, Seoul National University, Seoul 151–921, Korea
- Plant Genomics and Breeding Institute, Seoul National University, Seoul 151–921, Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151–921, Korea
| |
Collapse
|
36
|
Desai PR, van Wijlick L, Kurtz D, Juchimiuk M, Ernst JF. Hypoxia and Temperature Regulated Morphogenesis in Candida albicans. PLoS Genet 2015; 11:e1005447. [PMID: 26274602 PMCID: PMC4537295 DOI: 10.1371/journal.pgen.1005447] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Accepted: 07/15/2015] [Indexed: 01/31/2023] Open
Abstract
Candida albicans is a common commensal in the human gut but in predisposed patients it can become an important human fungal pathogen. As a commensal, C. albicans adapts to low-oxygen conditions and represses its hyphal development by the transcription factor Efg1, which under normoxia activates filamentation. The repressive hypoxic but not the normoxic function of Efg1 required its unmodified N-terminus, was prevented by phosphomimetic residues at normoxic phosphorylation sites T179 and T206 and occurred only at temperatures ≤35°C. Genome-wide binding sites for native Efg1 identified 300 hypoxia-specific target genes, which overlapped partially with hypoxic binding sites for Ace2, a known positive regulator of hypoxic filamentation. Transcriptional analyses revealed that EFG1, ACE2 and their identified targets BCR1 and BRG1 encode an interconnected regulatory hub, in which Efg1/Bcr1 act as negative and Ace2/Brg1 act as positive regulators of gene expression under hypoxia. In this circuit, the hypoxic function of Ace2 was stimulated by elevated CO2 levels. The hyperfilamentous phenotype of efg1 and bcr1 mutants depended on Ace2/Brg1 regulators and required increased expression of genes encoding Cek1 MAP kinase and its downstream target Cph1. The intricate temperature-dependent regulatory mechanisms under hypoxia suggest that C. albicans restricts hyphal morphogenesis in oxygen-poor body niches, possibly to persist as a commensal in the human host.
Collapse
Affiliation(s)
- Prashant R. Desai
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Lasse van Wijlick
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
- Manchot Graduate School Molecules of Infection, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Dagmar Kurtz
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Mateusz Juchimiuk
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Joachim F. Ernst
- Department Biologie, Molekulare Mykologie, Heinrich-Heine-Universität, Düsseldorf, Germany
- Manchot Graduate School Molecules of Infection, Heinrich-Heine-Universität, Düsseldorf, Germany
| |
Collapse
|
37
|
Use of anaerobic green fluorescent protein versus green fluorescent protein as reporter in lactic acid bacteria. Appl Microbiol Biotechnol 2015; 99:6865-77. [DOI: 10.1007/s00253-015-6770-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 06/08/2015] [Accepted: 06/11/2015] [Indexed: 01/09/2023]
|
38
|
Abstract
Only few Candida species, e.g., Candida albicans, Candida glabrata, Candida dubliniensis, and Candida parapsilosis, are successful colonizers of a human host. Under certain circumstances these species can cause infections ranging from superficial to life-threatening disseminated candidiasis. The success of C. albicans, the most prevalent and best studied Candida species, as both commensal and human pathogen depends on its genetic, biochemical, and morphological flexibility which facilitates adaptation to a wide range of host niches. In addition, formation of biofilms provides additional protection from adverse environmental conditions. Furthermore, in many host niches Candida cells coexist with members of the human microbiome. The resulting fungal-bacterial interactions have a major influence on the success of C. albicans as commensal and also influence disease development and outcome. In this chapter, we review the current knowledge of important survival strategies of Candida spp., focusing on fundamental fitness and virulence traits of C. albicans.
Collapse
Affiliation(s)
- Melanie Polke
- Research Group Microbial Immunology, Hans-Knoell-Institute, Jena, Germany; Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
| | - Bernhard Hube
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany; Friedrich-Schiller-University, Jena, Germany; Center for Sepsis Control and Care, Jena University Hospital, Jena, Germany
| | - Ilse D Jacobsen
- Research Group Microbial Immunology, Hans-Knoell-Institute, Jena, Germany; Friedrich-Schiller-University, Jena, Germany
| |
Collapse
|
39
|
Gupta P, Nath S, Meena R, Kumar N. Comparative effects of hypoxia and hypoxia mimetic cobalt chloride on in vitro adhesion, biofilm formation and susceptibility to amphotericin B of Candida glabrata. J Mycol Med 2014; 24:e169-77. [DOI: 10.1016/j.mycmed.2014.08.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 06/26/2014] [Accepted: 08/18/2014] [Indexed: 12/19/2022]
|
40
|
ChIP-seq and in vivo transcriptome analyses of the Aspergillus fumigatus SREBP SrbA reveals a new regulator of the fungal hypoxia response and virulence. PLoS Pathog 2014; 10:e1004487. [PMID: 25375670 PMCID: PMC4223079 DOI: 10.1371/journal.ppat.1004487] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 09/23/2014] [Indexed: 12/21/2022] Open
Abstract
The Aspergillus fumigatus sterol regulatory element binding protein (SREBP) SrbA belongs to the basic Helix-Loop-Helix (bHLH) family of transcription factors and is crucial for antifungal drug resistance and virulence. The latter phenotype is especially striking, as loss of SrbA results in complete loss of virulence in murine models of invasive pulmonary aspergillosis (IPA). How fungal SREBPs mediate fungal virulence is unknown, though it has been suggested that lack of growth in hypoxic conditions accounts for the attenuated virulence. To further understand the role of SrbA in fungal infection site pathobiology, chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq) was used to identify genes under direct SrbA transcriptional regulation in hypoxia. These results confirmed the direct regulation of ergosterol biosynthesis and iron uptake by SrbA in hypoxia and revealed new roles for SrbA in nitrate assimilation and heme biosynthesis. Moreover, functional characterization of an SrbA target gene with sequence similarity to SrbA identified a new transcriptional regulator of the fungal hypoxia response and virulence, SrbB. SrbB co-regulates genes involved in heme biosynthesis and demethylation of C4-sterols with SrbA in hypoxic conditions. However, SrbB also has regulatory functions independent of SrbA including regulation of carbohydrate metabolism. Loss of SrbB markedly attenuates A. fumigatus virulence, and loss of both SREBPs further reduces in vivo fungal growth. These data suggest that both A. fumigatus SREBPs are critical for hypoxia adaptation and virulence and reveal new insights into SREBPs' complex role in infection site adaptation and fungal virulence. Despite improvements in diagnostics and antifungal drug treatments, mortality rates from invasive mold infections remain high. Defining the fungal adaptation and growth mechanisms at the infection site microenvironment is one research focus that is expected to improve treatment of established invasive fungal infections. The Aspergillus fumigatus transcription factor SrbA is a major regulator of the fungal response to hypoxia found at sites of invasive fungal growth in vivo. In this study, new insights into how SrbA mediates hypoxia adaptation and virulence were revealed through identification of direct transcriptional targets of SrbA under hypoxic conditions. A major novel finding from these studies is the identification of a critical role in fungal hypoxia adaptation and virulence of an SrbA target gene, srbB, which is also in the SREBP family. SrbB plays a major role in regulation of heme biosynthesis and carbohydrate metabolism early in the response to hypoxia. The discovery of SrbA-dependent regulation of srbB gene expression, and the target genes they regulate opens new avenues to understand how SREBPs and their target genes mediate adaptation to the in vivo infection site microenvironment and responses to current antifungal therapies.
Collapse
|
41
|
Trendeleva TA, Aliverdieva DA, Zvyagilskaya RA. Mechanisms of sensing and adaptive responses to low oxygen conditions in mammals and yeasts. BIOCHEMISTRY (MOSCOW) 2014; 79:750-60. [DOI: 10.1134/s0006297914080033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
42
|
Changes in glutathione-dependent redox status and mitochondrial energetic strategies are part of the adaptive response during the filamentation process in Candida albicans. Biochim Biophys Acta Mol Basis Dis 2014; 1842:1855-69. [PMID: 25018088 DOI: 10.1016/j.bbadis.2014.07.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 07/04/2014] [Accepted: 07/06/2014] [Indexed: 01/05/2023]
Abstract
Candida albicans is an opportunist pathogen responsible for a large spectrum of infections, from superficial mycosis to systemic diseases called candidiasis. Its ability to grow in various morphological forms, such as unicellular budding yeast, filamentous pseudohyphae and hyphae, contributes to its survival in the diverse microenvironments it encounters in the host. During infection in vivo, C. albicans is faced with high levels of reactive oxygen species (ROS) generated by phagocytes, and the thiol-dependent redox status of the cells reflects their levels of oxidative stress. We investigated the role of glutathione during the transition between the yeast and hyphal forms of the pathogen, in relation to possible changes in mitochondrial bioenergetic pathways. Using various growth media and selective mutations affecting the filamentation process, we showed that C. albicans filamentation was always associated with a depletion of intracellular glutathione levels. Moreover, the induction of hypha formation resulted in general changes in thiol metabolism, including the oxidation of cell surface -SH groups and glutathione excretion. Metabolic adaptation involved tricarboxylic acid (TCA) cycle activation, acceleration of mitochondrial respiration and a redistribution of electron transfer pathways, with an increase in the contribution of the alternative oxidase and rotenone-insensitive dehydrogenase. Changes in redox status and apparent oxidative stress may be necessary to the shift to adaptive metabolic pathways, ensuring normal mitochondrial function and adenosine triphosphate (ATP) levels. The consumption of intracellular glutathione levels during the filamentation process may thus be the price paid by C. albicans for survival in the conditions encountered in the host.
Collapse
|
43
|
Lu Y, Su C, Solis NV, Filler SG, Liu H. Synergistic regulation of hyphal elongation by hypoxia, CO(2), and nutrient conditions controls the virulence of Candida albicans. Cell Host Microbe 2014; 14:499-509. [PMID: 24237696 DOI: 10.1016/j.chom.2013.10.008] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 08/28/2013] [Accepted: 09/20/2013] [Indexed: 01/19/2023]
Abstract
Candida albicans reversibly switches between yeast and hyphal morphologies, with hyphae being associated with virulence. Hyphal initiation and maintenance depend on host environment sensing. Hyphal maintenance in vitro requires chromatin remodeling of hypha-specific gene promoters, although disrupting chromatin-remodeling does not disrupt C. albicans hyphal elongation and virulence during invasive infection. We find that the combination of hypoxia and high CO2, but neither condition alone, maintains hyphal elongation, even in mutants lacking the nutrient-responsive chromatin-remodeling pathway. Ume6, the transcriptional activator of hypha-specific genes, is stabilized via regulation by Ofd1, a prolyl hydroxylase family member inhibited by hypoxia, and by an uncharacterized pathway that senses high CO2. Virulence and hyphal elongation in vivo are attenuated only when the parallelly acting Ume6 stabilization and chromatin-remodeling pathways are both blocked. The evolution of redundant signaling pathways allowing C. albicans to adapt to varied host environments may explain this commensal's success as a pathogen.
Collapse
Affiliation(s)
- Yang Lu
- Department of Biological Chemistry, University of California, Irvine, Irvine, CA 92697, USA
| | | | | | | | | |
Collapse
|
44
|
Landete JM, Peirotén Á, Rodríguez E, Margolles A, Medina M, Arqués JL. Anaerobic green fluorescent protein as a marker of Bifidobacterium strains. Int J Food Microbiol 2014; 175:6-13. [DOI: 10.1016/j.ijfoodmicro.2014.01.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 01/11/2014] [Indexed: 12/20/2022]
|
45
|
Modeling the transcriptional regulatory network that controls the early hypoxic response in Candida albicans. EUKARYOTIC CELL 2014; 13:675-90. [PMID: 24681685 DOI: 10.1128/ec.00292-13] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We determined the changes in transcriptional profiles that occur in the first hour following the transfer of Candida albicans to hypoxic growth conditions. The impressive speed of this response is not compatible with current models of fungal adaptation to hypoxia that depend on the depletion of sterol and heme. Functional analysis using Gene Set Enrichment Analysis (GSEA) identified the Sit4 phosphatase, Ccr4 mRNA deacetylase, and Sko1 transcription factor (TF) as potential regulators of the early hypoxic response. Cells mutated in these and other regulators exhibit a delay in their transcriptional responses to hypoxia. Promoter occupancy data for 29 TFs were combined with the transcriptional profiles of 3,111 in vivo target genes in a Network Component Analysis (NCA) to produce a model of the dynamic and highly interconnected TF network that controls this process. With data from the TF network obtained from a variety of sources, we generated an edge and node model that was capable of separating many of the hypoxia-upregulated and -downregulated genes. Upregulated genes are centered on Tye7, Upc2, and Mrr1, which are associated with many of the gene promoters that exhibit the strongest activations. The connectivity of the model illustrates the high redundancy of this response system and the challenges that lie in determining the individual contributions of specific TFs. Finally, treating cells with an inhibitor of the oxidative phosphorylation chain mimics most of the early hypoxic profile, which suggests that this response may be initiated by a drop in ATP production.
Collapse
|
46
|
Ramachandra S, Linde J, Brock M, Guthke R, Hube B, Brunke S. Regulatory networks controlling nitrogen sensing and uptake in Candida albicans. PLoS One 2014; 9:e92734. [PMID: 24651113 PMCID: PMC3961412 DOI: 10.1371/journal.pone.0092734] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 02/24/2014] [Indexed: 12/22/2022] Open
Abstract
Nitrogen is one of the key nutrients for microbial growth. During infection, pathogenic fungi like C. albicans need to acquire nitrogen from a broad range of different and changing sources inside the host. Detecting the available nitrogen sources and adjusting the expression of genes for their uptake and degradation is therefore crucial for survival and growth as well as for establishing an infection. Here, we analyzed the transcriptional response of C. albicans to nitrogen starvation and feeding with the infection-relevant nitrogen sources arginine and bovine serum albumin (BSA), representing amino acids and proteins, respectively. The response to nitrogen starvation was marked by an immediate repression of protein synthesis and an up-regulation of general amino acid permeases, as well as an up-regulation of autophagal processes in its later stages. Feeding with arginine led to a fast reduction in expression of general permeases for amino acids and to resumption of protein synthesis. The response to BSA feeding was generally slower, and was additionally characterized by an up-regulation of oligopeptide transporter genes. From time-series data, we inferred network interaction models for genes relevant in nitrogen detection and uptake. Each individual network was found to be largely specific for the experimental condition (starvation or feeding with arginine or BSA). In addition, we detected several novel connections between regulator and effector genes, with putative roles in nitrogen uptake. We conclude that C. albicans adopts a particular nitrogen response network, defined by sets of specific gene-gene connections for each environmental condition. All together, they form a grid of possible gene regulatory networks, increasing the transcriptional flexibility of C. albicans.
Collapse
Affiliation(s)
- Shruthi Ramachandra
- Department of Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Jörg Linde
- Department of Systems Biology & Bioinformatics, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Matthias Brock
- Department of Microbial Biochemistry and Physiology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
| | - Reinhard Guthke
- Department of Systems Biology & Bioinformatics, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
- Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
- Friedrich Schiller University, Jena, Germany
| | - Sascha Brunke
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute, Jena, Germany
- Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
- * E-mail:
| |
Collapse
|
47
|
Maguire SL, Wang C, Holland LM, Brunel F, Neuvéglise C, Nicaud JM, Zavrel M, White TC, Wolfe KH, Butler G. Zinc finger transcription factors displaced SREBP proteins as the major Sterol regulators during Saccharomycotina evolution. PLoS Genet 2014; 10:e1004076. [PMID: 24453983 PMCID: PMC3894159 DOI: 10.1371/journal.pgen.1004076] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 11/18/2013] [Indexed: 12/26/2022] Open
Abstract
In most eukaryotes, including the majority of fungi, expression of sterol biosynthesis genes is regulated by Sterol-Regulatory Element Binding Proteins (SREBPs), which are basic helix-loop-helix transcription activators. However, in yeasts such as Saccharomyces cerevisiae and Candida albicans sterol synthesis is instead regulated by Upc2, an unrelated transcription factor with a Gal4-type zinc finger. The SREBPs in S. cerevisiae (Hms1) and C. albicans (Cph2) have lost a domain, are not major regulators of sterol synthesis, and instead regulate filamentous growth. We report here that rewiring of the sterol regulon, with Upc2 taking over from SREBP, likely occurred in the common ancestor of all Saccharomycotina. Yarrowia lipolytica, a deep-branching species, is the only genome known to contain intact and full-length orthologs of both SREBP (Sre1) and Upc2. Deleting YlUPC2, but not YlSRE1, confers susceptibility to azole drugs. Sterol levels are significantly reduced in the YlUPC2 deletion. RNA-seq analysis shows that hypoxic regulation of sterol synthesis genes in Y. lipolytica is predominantly mediated by Upc2. However, YlSre1 still retains a role in hypoxic regulation; growth of Y. lipolytica in hypoxic conditions is reduced in a Ylupc2 deletion and is abolished in a Ylsre1/Ylupc2 double deletion, and YlSre1 regulates sterol gene expression during hypoxia adaptation. We show that YlSRE1, and to a lesser extent YlUPC2, are required for switching from yeast to filamentous growth in hypoxia. Sre1 appears to have an ancestral role in the regulation of filamentation, which became decoupled from its role in sterol gene regulation by the arrival of Upc2 in the Saccharomycotina.
Collapse
Affiliation(s)
- Sarah L. Maguire
- UCD School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin, Ireland
| | - Can Wang
- UCD School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin, Ireland
| | - Linda M. Holland
- UCD School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin, Ireland
| | - François Brunel
- INRA UMR1319 Micalis, AgroParisTech, Jouy-en-Josas, France
- CNRS, Micalis, Jouy-en-Josas, France
| | - Cécile Neuvéglise
- INRA UMR1319 Micalis, AgroParisTech, Jouy-en-Josas, France
- CNRS, Micalis, Jouy-en-Josas, France
| | - Jean-Marc Nicaud
- INRA UMR1319 Micalis, AgroParisTech, Jouy-en-Josas, France
- CNRS, Micalis, Jouy-en-Josas, France
| | - Martin Zavrel
- University of Missouri-Kansas City, School of Biological Sciences, Cell Biology and Biophysics, Kansas City, Missouri, United States of America
| | - Theodore C. White
- University of Missouri-Kansas City, School of Biological Sciences, Cell Biology and Biophysics, Kansas City, Missouri, United States of America
| | - Kenneth H. Wolfe
- UCD School of Medicine and Medical Science, Conway Institute, University College Dublin, Belfield, Dublin, Ireland
| | - Geraldine Butler
- UCD School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin, Ireland
- * E-mail:
| |
Collapse
|
48
|
Wingen M, Potzkei J, Endres S, Casini G, Rupprecht C, Fahlke C, Krauss U, Jaeger KE, Drepper T, Gensch T. The photophysics of LOV-based fluorescent proteins – new tools for cell biology. Photochem Photobiol Sci 2014; 13:875-83. [DOI: 10.1039/c3pp50414j] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
In this study photophysical characteristics of LOV-based fluorescent proteins which are essential for analytic methods as well as imaging approaches have been comparatively analyzed in detail.
Collapse
Affiliation(s)
- Marcus Wingen
- Institute of Molecular Enzyme Technology
- Heinrich-Heine-University Düsseldorf
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| | - Janko Potzkei
- Institute of Molecular Enzyme Technology
- Heinrich-Heine-University Düsseldorf
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| | - Stephan Endres
- Institute of Molecular Enzyme Technology
- Heinrich-Heine-University Düsseldorf
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| | - Giorgia Casini
- Institute of Complex Systems 4 (ICS-4
- Cellular Biophysics)
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| | - Christian Rupprecht
- Institute of Molecular Enzyme Technology
- Heinrich-Heine-University Düsseldorf
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| | - Christoph Fahlke
- Institute of Complex Systems 4 (ICS-4
- Cellular Biophysics)
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| | - Ulrich Krauss
- Institute of Molecular Enzyme Technology
- Heinrich-Heine-University Düsseldorf
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| | - Karl-Erich Jaeger
- Institute of Molecular Enzyme Technology
- Heinrich-Heine-University Düsseldorf
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| | - Thomas Drepper
- Institute of Molecular Enzyme Technology
- Heinrich-Heine-University Düsseldorf
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| | - Thomas Gensch
- Institute of Complex Systems 4 (ICS-4
- Cellular Biophysics)
- Forschungszentrum Jülich
- 52425 Jülich, Germany
| |
Collapse
|
49
|
Mitochondrial metabolism and stress response of yeast: Applications in fermentation technologies. J Biosci Bioeng 2013; 117:383-93. [PMID: 24210052 DOI: 10.1016/j.jbiosc.2013.09.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 08/27/2013] [Accepted: 09/17/2013] [Indexed: 11/22/2022]
Abstract
Mitochondria are sites of oxidative respiration. During sake brewing, sake yeasts are exposed to long periods of hypoxia; the structure, role, and metabolism of mitochondria of sake yeasts have not been studied in detail. It was first elucidated that the mitochondrial structure of sake yeast transforms from filamentous to dotted structure during sake brewing, which affects malate metabolism. Based on the information of yeast mitochondria during sake brewing, practical technologies have been developed; (i) breeding pyruvate-underproducing sake yeast by the isolation of a mutant resistant to an inhibitor of mitochondrial pyruvate transport; and (ii) modifying malate and succinate production by manipulating mitochondrial activity. During the bread-making process, baker's yeast cells are exposed to a variety of baking-associated stresses, such as freeze-thaw, air-drying, and high sucrose concentrations. These treatments induce oxidative stress generating reactive oxygen species due to mitochondrial damage. A novel metabolism of proline and arginine catalyzed by N-acetyltransferase Mpr1 in the mitochondria eventually leads to synthesis of nitric oxide, which confers oxidative stress tolerance on yeast cells. The enhancement of proline and arginine metabolism could be promising for breeding novel baker's yeast strains that are tolerant to multiple baking-associated stresses. These new and practical methods provide approaches to improve the processes in the field of industrial fermentation technologies.
Collapse
|
50
|
Novel Regulatory Mechanisms of Pathogenicity and Virulence to Combat MDR in Candida albicans. Int J Microbiol 2013; 2013:240209. [PMID: 24163696 PMCID: PMC3791847 DOI: 10.1155/2013/240209] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Revised: 08/15/2013] [Accepted: 08/15/2013] [Indexed: 01/19/2023] Open
Abstract
Continuous deployment of antifungals in treating infections caused by dimorphic opportunistic pathogen Candida albicans has led to the emergence of drug resistance resulting in cross-resistance to many unrelated drugs, a phenomenon termed multidrug resistance (MDR). Despite the current understanding of major factors which contribute to MDR mechanisms, there are many lines of evidence suggesting that it is a complex interplay of multiple factors which may be contributed by still unknown mechanisms. Coincidentally with the increased usage of antifungal drugs, the number of reports for antifungal drug resistance has also increased which further highlights the need for understanding novel molecular mechanisms which can be explored to combat MDR, namely, ROS, iron, hypoxia, lipids, morphogenesis, and transcriptional and signaling networks. Considering the worrying evolution of MDR and significance of C. albicans being the most prevalent human fungal pathogen, this review summarizes these new regulatory mechanisms which could be exploited to prevent MDR development in C. albicans as established from recent studies.
Collapse
|