1
|
Ball B, Sukumaran A, Krieger JR, Geddes-McAlister J. Comparative Cross-Kingdom DDA- and DIA-PASEF Proteomic Profiling Reveals Novel Determinants of Fungal Virulence and a Putative Druggable Target. J Proteome Res 2024. [PMID: 39140824 DOI: 10.1021/acs.jproteome.4c00255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
Accurate and reliable detection of fungal pathogens presents an important hurdle to manage infections, especially considering that fungal pathogens, including the globally important human pathogen, Cryptococcus neoformans, have adapted diverse mechanisms to survive the hostile host environment and moderate virulence determinant production during coinfections. These pathogen adaptations present an opportunity for improvements (e.g., technological and computational) to better understand the interplay between a host and a pathogen during disease to uncover new strategies to overcome infection. In this study, we performed comparative proteomic profiling of an in vitro coinfection model across a range of fungal and bacterial burden loads in macrophages. Comparing data-dependent acquisition and data-independent acquisition enabled with parallel accumulation serial fragmentation technology, we quantified changes in dual-perspective proteome remodeling. We report enhanced and novel detection of pathogen proteins with data-independent acquisition-parallel accumulation serial fragmentation (DIA-PASEF), especially for fungal proteins during single and dual infection of macrophages. Further characterization of a fungal protein detected only with DIA-PASEF uncovered a novel determinant of fungal virulence, including altered capsule and melanin production, thermotolerance, and macrophage infectivity, supporting proteomics advances for the discovery of a novel putative druggable target to suppress C. neoformans pathogenicity.
Collapse
Affiliation(s)
- Brianna Ball
- Department of Molecular and Cellular Biology, University of Guelph, Guelph N1G 2W1, Ontario, Canada
| | - Arjun Sukumaran
- Department of Molecular and Cellular Biology, University of Guelph, Guelph N1G 2W1, Ontario, Canada
| | | | | |
Collapse
|
2
|
Folorunso OS, Sebolai OM. A Limited Number of Amino Acid Permeases Are Crucial for Cryptococcus neoformans Survival and Virulence. Int J Microbiol 2024; 2024:5566438. [PMID: 39148675 PMCID: PMC11326883 DOI: 10.1155/2024/5566438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 06/26/2024] [Accepted: 07/12/2024] [Indexed: 08/17/2024] Open
Abstract
One unique attribute of Cryptococcus neoformans is its ability to procure essential monomers from its surroundings to survive in diverse environments. Preferentially, sugars are the energy sources for this opportunistic pathogenic fungus under the carbon catabolite repression (CCR); however, sugar restriction induces alternative use of low molecular weight alcohol, organic acids, and amino acids. The expression of transmembrane amino acid permeases (Aaps) allows C. neoformans to utilize different amino acids and their conjugates, notwithstanding under the nitrogen catabolite repression (NCR). Being referred to as global permeases, there is a notion that all cryptococcal Aaps are important to survival and virulence. This functional divergence makes alternative drug targeting against Cryptococcus a challenge. We examine the functions and regulations of C. neoformans Aap variants with the aim of rationalizing their relevance to cryptococcal cell survival and virulence. Based on nutrient bioavailability, we linked the Cac1 pathway to Ras1 activation for thermotolerance that provides a temperature cushion for Aap activity under physiological conditions. Lastly, mutants of Aaps are examined for significant phenotypic deficiencies/advantages, which buttress the specific importance of limited numbers of Aaps involved in cryptococcal infections.
Collapse
Affiliation(s)
- Olufemi S Folorunso
- Department of Microbiology and Biochemistry University of the Free State, 205 Nelson Mandela Drive, Park West, Bloemfontein 9301, South Africa
| | - Olihile M Sebolai
- Department of Microbiology and Biochemistry University of the Free State, 205 Nelson Mandela Drive, Park West, Bloemfontein 9301, South Africa
| |
Collapse
|
3
|
Hughes ES, Tuck LR, He Z, Ballou ER, Wallace EWJ. A trade-off between proliferation and defense in the fungal pathogen Cryptococcus at alkaline pH is controlled by the transcription factor GAT201. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.14.543486. [PMID: 37398450 PMCID: PMC10312749 DOI: 10.1101/2023.06.14.543486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Cryptococcus is a fungal pathogen whose virulence relies on proliferation in and dissemination to host sites, and on synthesis of a defensive yet metabolically costly polysaccharide capsule. Regulatory pathways required for Cryptococcus virulence include a GATA-like transcription factor, Gat201, that regulates Cryptococcal virulence in both capsule-dependent and capsule-independent ways. Here we show that Gat201 is part of a negative regulatory pathway that limits fungal survival at alkaline pH. RNA-seq analysis found strong induction of GAT201 expression within minutes of transfer to RPMI media at alkaline pH. Microscopy, growth curves, and colony forming unit assays show that in RPMI at alkaline pH wild-type Cryptococcus neoformans yeast cells produce capsule but do not bud or maintain viability, while gat201Δ cells make buds and maintain viability, yet fail to produce capsule. GAT201 is required for transcriptional upregulation of a specific set of genes, the majority of which are direct Gat201 targets. Evolutionary analysis shows that Gat201 is in a subfamily of GATA-like transcription factors that is conserved within pathogenic fungi but absent in model yeasts. This work identifies the Gat201 pathway as controlling a trade-off between proliferation and production of defensive capsule. The assays established here will allow characterisation of the mechanisms of action of the Gat201 pathway. Together, our findings urge improved understanding of the regulation of proliferation as a driver of fungal pathogenesis.
Collapse
Affiliation(s)
- Elizabeth S Hughes
- Institute for Cell Biology, and Centre for Engineering Biology, School of Biological Sciences, The University of Edinburgh
| | - Laura R Tuck
- Institute for Cell Biology, and Centre for Engineering Biology, School of Biological Sciences, The University of Edinburgh
| | - Zhenzhen He
- Institute for Cell Biology, and Centre for Engineering Biology, School of Biological Sciences, The University of Edinburgh
| | | | - Edward W J Wallace
- Institute for Cell Biology, and Centre for Engineering Biology, School of Biological Sciences, The University of Edinburgh
| |
Collapse
|
4
|
Meng Y, Ni Y, Li Z, Jiang T, Sun T, Li Y, Gao X, Li H, Suo C, Li C, Yang S, Lan T, Liao G, Liu T, Wang P, Ding C. Interplay between acetylation and ubiquitination of imitation switch chromatin remodeler Isw1 confers multidrug resistance in Cryptococcus neoformans. eLife 2024; 13:e85728. [PMID: 38251723 PMCID: PMC10834027 DOI: 10.7554/elife.85728] [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: 12/21/2022] [Accepted: 01/21/2024] [Indexed: 01/23/2024] Open
Abstract
Cryptococcus neoformans poses a threat to human health, but anticryptococcal therapy is hampered by the emergence of drug resistance, whose underlying mechanisms remain poorly understood. Herein, we discovered that Isw1, an imitation switch chromatin remodeling ATPase, functions as a master modulator of genes responsible for in vivo and in vitro multidrug resistance in C. neoformans. Cells with the disrupted ISW1 gene exhibited profound resistance to multiple antifungal drugs. Mass spectrometry analysis revealed that Isw1 is both acetylated and ubiquitinated, suggesting that an interplay between these two modification events exists to govern Isw1 function. Mutagenesis studies of acetylation and ubiquitination sites revealed that the acetylation status of Isw1K97 coordinates with its ubiquitination processes at Isw1K113 and Isw1K441 through modulating the interaction between Isw1 and Cdc4, an E3 ligase. Additionally, clinical isolates of C. neoformans overexpressing the degradation-resistant ISW1K97Q allele showed impaired drug-resistant phenotypes. Collectively, our studies revealed a sophisticated acetylation-Isw1-ubiquitination regulation axis that controls multidrug resistance in C. neoformans.
Collapse
Affiliation(s)
- Yang Meng
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| | - Yue Ni
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| | - Zhuoran Li
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| | - Tianhang Jiang
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| | - Tianshu Sun
- Department of Scientific Research, Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Yanjian Li
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| | - Xindi Gao
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| | - Hailong Li
- NHC Key Laboratory of AIDS Immunology, The First Affiliated Hospital of China Medical UniversityShenyangChina
| | - Chenhao Suo
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| | - Chao Li
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| | - Sheng Yang
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| | - Tian Lan
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| | - Guojian Liao
- College of Pharmaceutical Sciences, Southwest UniversityChongqingChina
| | - Tongbao Liu
- Medical Research Institute, Southwest UniversityChongqingChina
| | - Ping Wang
- Department of Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center New OrleansNew OrleansUnited States
| | - Chen Ding
- College of Life and Health Sciences, Northeastern UniversityShenyangChina
| |
Collapse
|
5
|
Navale AM. Glucose Transporter and Sensor Mechanisms in Fungal Pathogens as Potential Drug Targets. Curr Rev Clin Exp Pharmacol 2024; 19:250-258. [PMID: 37861001 DOI: 10.2174/0127724328263050230923154326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 08/02/2023] [Accepted: 08/25/2023] [Indexed: 10/21/2023]
Abstract
Fungal infections are emerging as major health challenges in recent years. The development of resistance against existing antifungal agents needs urgent attention and action. The limited classes of antifungal drugs available, their tendency to cause adverse effects, lack of effectiveness, etc., are the major limitations of current therapy. Thus, there is a pressing demand for new antifungal drug classes to cope with the present circumstances. Glucose is the key source of energy for all organisms, including fungi. Glucose plays a crucial role as a source of carbon and energy for processes like virulence, growth, invasion, biofilm formation, and resistance development. The glucose transport and sensing mechanisms are well developed in these organisms as an important strategy to sustain survival. Modulating these transport or sensor mechanisms may serve as an important strategy to inhibit fungal growth. Moreover, the structural difference between human and fungal glucose transporters makes them more appealing as drug targets. Limited literature is available for fungal glucose entry mechanisms. This review provides a comprehensive account of sugar transport mechanisms in common fungal pathogens.
Collapse
Affiliation(s)
- Archana Mohit Navale
- Department of Pharmacology, Parul Institute of Pharmacy, Parul University, Limda, India
| |
Collapse
|
6
|
Hommel B, Sturny-Leclère A, Alanio A. In Vitro Titan Cell Generation in Cryptococcus neoformans and Automated Cell Size Measurements. Methods Mol Biol 2024; 2775:385-391. [PMID: 38758332 DOI: 10.1007/978-1-0716-3722-7_26] [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: 05/18/2024]
Abstract
A special feature of the human fungal pathogen Cryptococcus neoformans is its morphological changes triggered by the interaction with the host. During infection, a specific increase in cell size is observed, particularly in lung tissue, from a typical cell size of 5-7 μm cells to cells larger than 10 μm, dubbed titan cells (TCs). However, the study of this specific cell subpopulation was, until now, only possible via recovery of TCs from lungs of mice during experimental infections where stable and reproducible generation of TCs occurs.The protocol described here generates TCs using in vitro conditions and measures cell size using a rapid, automated method. TC generation in vitro is robust and reproducible, generating yeast cells harboring the same characteristics of TCs generated in vivo.
Collapse
Affiliation(s)
- Benjamin Hommel
- Translational Mycology Research Group, Institut Pasteur, Université Paris Cité, Centre National de Référence Mycoses Invasives et Antifongiques, Département de Mycologie, Paris, France
| | - Aude Sturny-Leclère
- Institut Pasteur, Université Paris Cité,National Reference Center for Invasive Mycoses and Antifungals, Paris, France
| | - Alexandre Alanio
- Translational Mycology Research Group, Institut Pasteur, Université Paris Cité, Centre National de Référence Mycoses Invasives et Antifongiques, Département de Mycologie, Paris, France.
- Laboratoire de parasitologie-mycologie, AP-HP, Hôpital Saint-Louis, Paris, France.
| |
Collapse
|
7
|
Upadhya R, Probst C, Alspaugh JA, Lodge JK. Measuring Stress Phenotypes in Cryptococcus neoformans. Methods Mol Biol 2024; 2775:277-303. [PMID: 38758325 DOI: 10.1007/978-1-0716-3722-7_19] [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: 05/18/2024]
Abstract
Cryptococcus neoformans is an opportunistic human fungal pathogen capable of surviving in a wide range of environments and hosts. It has been developed as a model organism to study fungal pathogenesis due to its fully sequenced haploid genome and optimized gene deletion and mutagenesis protocols. These methods have greatly aided in determining the relationship between Cryptococcus genotype and phenotype. Furthermore, the presence of congenic mata and matα strains associated with a defined sexual cycle has helped further understand cryptococcal biology. Several in vitro stress conditions have been optimized to closely mimic the stress that yeast encounter in the environment or within the infected host. These conditions have proven to be extremely useful in elucidating the role of several genes in allowing yeast to adapt and survive in hostile external environments. This chapter describes various in vitro stress conditions that could be used to test the sensitivity of different mutant strains, as well as the protocol for preparing them. We have also included a list of mutants that could be used as a positive control strain when testing the sensitivity of the desired strain to a specific stress.
Collapse
Affiliation(s)
- Rajendra Upadhya
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA.
| | - Corinna Probst
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA
- Department of Medicine, Duke University School of Medicine, Durham, NC, USA
| | - J Andrew Alspaugh
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA
- Department of Medicine, Duke University School of Medicine, Durham, NC, USA
| | - Jennifer K Lodge
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC, USA
| |
Collapse
|
8
|
Suo C, Gao Y, Ding C, Sun T. The function and regulation of heat shock transcription factor in Cryptococcus. Front Cell Infect Microbiol 2023; 13:1195968. [PMID: 37168390 PMCID: PMC10165103 DOI: 10.3389/fcimb.2023.1195968] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 04/10/2023] [Indexed: 05/13/2023] Open
Abstract
Cryptococcus species are opportunistic human fungal pathogens. Survival in a hostile environment, such as the elevated body temperatures of transmitting animals and humans, is crucial for Cryptococcus infection. Numerous intriguing investigations have shown that the Hsf family of thermotolerance transcription regulators plays a crucial role in the pathogen-host axis of Cryptococcus. Although Hsf1 is known to be a master regulator of the heat shock response through the activation of gene expression of heat shock proteins (Hsps). Hsf1 and other Hsfs are multifaceted transcription regulators that regulate the expression of genes involved in protein chaperones, metabolism, cell signal transduction, and the electron transfer chain. In Saccharomyces cerevisiae, a model organism, Hsf1's working mechanism has been intensively examined. Nonetheless, the link between Hsfs and Cryptococcus pathogenicity remains poorly understood. This review will focus on the transcriptional regulation of Hsf function in Cryptococcus, as well as potential antifungal treatments targeting Hsf proteins.
Collapse
Affiliation(s)
- Chenhao Suo
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Yiru Gao
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Chen Ding
- College of Life and Health Sciences, Northeastern University, Shenyang, China
- *Correspondence: Tianshu Sun, ; Chen Ding,
| | - Tianshu Sun
- Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, China
- Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
- *Correspondence: Tianshu Sun, ; Chen Ding,
| |
Collapse
|
9
|
Maccaro JJ, Moreira Salgado JF, Klinger E, Argueta Guzmán MP, Ngor L, Stajich JE, McFrederick QS. Comparative genomics reveals that metabolism underlies evolution of entomopathogenicity in bee-loving Ascosphaera spp. fungi. J Invertebr Pathol 2022; 194:107804. [PMID: 35933037 PMCID: PMC10793876 DOI: 10.1016/j.jip.2022.107804] [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: 05/16/2022] [Revised: 07/16/2022] [Accepted: 07/26/2022] [Indexed: 10/16/2022]
Abstract
Ascosphaera (Eurotiomycetes: Onygenales) is a diverse genus of fungi that is exclusively found in association with bee nests and comprises both saprophytic and entomopathogenic species. To date, most genomic analyses have been focused on the honeybee pathogen A. apis, and we lack a genomic understanding of how pathogenesis evolved more broadly in the genus. To address this gap we sequenced the genomes of the leaf-cutting bee pathogen A. aggregata as well as three commensal species: A. pollenicola, A. atra and A. acerosa. De novo annotation and comparison of the assembled genomes was carried out, including the previously published genome of A. apis. To identify candidate virulence genes in the pathogenic species, we performed secondary metabolite-oriented analyses and clustering of biosynthetic gene clusters (BGCs). Additionally, we captured single copy orthologs to infer their phylogeny and created codon-aware alignments to determine orthologs under selective pressure in our pathogenic species. Our results show several shared BGCs between A. apis, A. aggregata and A. pollenicola, with antifungal resistance related genes present in the bee pathogens and commensals. Genes involved in metabolism and protein processing exhibit signatures of enrichment and positive selection under a fitted branch-site model. Additional known virulence genes in A. pollenicola, A. acerosa and A. atra are identified, supporting previous hypotheses that these commensals may be opportunistic pathogens. Finally, we discuss the importance of such genes in other fungal pathogens, suggesting a common route to evolution of pathogenicity in Ascosphaera.
Collapse
Affiliation(s)
- J J Maccaro
- Department of Entomology, University of California Riverside, Riverside, CA, USA
| | - J F Moreira Salgado
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, RJ, Brazil; Department of Microbiology and Plant Pathology, University of California Riverside, Riverside, CA, USA
| | - E Klinger
- Department of Entomology, The Ohio State University, Columbus, OH, USA; USDA-ARS Pollinating Insect Biology Management Systematics Research Unit, Logan, UT, USA
| | - M P Argueta Guzmán
- Department of Entomology, University of California Riverside, Riverside, CA, USA
| | - L Ngor
- Department of Entomology, University of California Riverside, Riverside, CA, USA
| | - J E Stajich
- Department of Microbiology and Plant Pathology, University of California Riverside, Riverside, CA, USA.
| | - Q S McFrederick
- Department of Entomology, University of California Riverside, Riverside, CA, USA.
| |
Collapse
|
10
|
Saidykhan L, Correia J, Romanyuk A, Peacock AFA, Desanti GE, Taylor-Smith L, Makarova M, Ballou ER, May RC. An in vitro method for inducing titan cells reveals novel features of yeast-to-titan switching in the human fungal pathogen Cryptococcus gattii. PLoS Pathog 2022; 18:e1010321. [PMID: 35969643 PMCID: PMC9426920 DOI: 10.1371/journal.ppat.1010321] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 08/30/2022] [Accepted: 07/07/2022] [Indexed: 12/15/2022] Open
Abstract
Cryptococcosis is a potentially lethal fungal infection of humans caused by organisms within the Cryptococcus neoformans/gattii species complex. Whilst C. neoformans is a relatively common pathogen of immunocompromised individuals, C. gattii is capable of acting as a primary pathogen of immunocompetent individuals. Within the host, both species undergo morphogenesis to form titan cells: exceptionally large cells that are critical for disease establishment. To date, the induction, defining attributes, and underlying mechanism of titanisation have been mainly characterized in C. neoformans. Here, we report the serendipitous discovery of a simple and robust protocol for in vitro induction of titan cells in C. gattii. Using this in vitro approach, we reveal a remarkably high capacity for titanisation within C. gattii, especially in strains associated with the Pacific Northwest Outbreak, and characterise strain-specific differences within the clade. In particular, this approach demonstrates for the first time that cell size changes, DNA amplification, and budding are not always synchronous during titanisation. Interestingly, however, exhibition of these cell cycle phenotypes was correlated with genes associated with cell cycle progression including CDC11, CLN1, BUB2, and MCM6. Finally, our findings reveal exogenous p-Aminobenzoic acid to be a key inducer of titanisation in this organism. Consequently, this approach offers significant opportunities for future exploration of the underlying mechanism of titanisation in this genus.
Collapse
Affiliation(s)
- Lamin Saidykhan
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
- Division of Physical and Natural Science, University of The Gambia, Brikama, The Gambia
| | - Joao Correia
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
| | - Andrey Romanyuk
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
- School of Chemistry, University of Birmingham, Edgbaston, United Kingdom
| | - Anna F. A. Peacock
- School of Chemistry, University of Birmingham, Edgbaston, United Kingdom
| | - Guillaume E. Desanti
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
| | - Leanne Taylor-Smith
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
| | - Maria Makarova
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
| | - Elizabeth R. Ballou
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
- * E-mail: (ERB); (RCM)
| | - Robin C. May
- Institute of Microbiology & Infection and School of Biosciences, University of Birmingham, Edgbaston, United Kingdom
- * E-mail: (ERB); (RCM)
| |
Collapse
|
11
|
Jezewski AJ, Beattie SR, Alden KM, Krysan DJ. Gluconate Kinase Is Required for Gluconate Assimilation and Sporulation in Cryptococcus neoformans. Microbiol Spectr 2022; 10:e0030122. [PMID: 35412378 PMCID: PMC9045243 DOI: 10.1128/spectrum.00301-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/19/2022] [Indexed: 11/20/2022] Open
Abstract
Cryptococcus neoformans is an environmental yeast and an opportunistic human pathogen. The ability to cause disease depends on the ability to adapt to the human host. Previous studies implicated infectivity-related kinase 3 (IRK3, CNAG_03048) as required for establishing an infection. We genetically and biochemically characterized IRK3 as a gluconate kinase and propose the name GNK1. This metabolic enzyme utilizes gluconate to produce 6-phosphogluconate as part of the alternative oxidative phase of the pentose phosphate pathway (AOXPPP). The presence of GNK1 confirms that the AOXPPP is present and able to compensate for loss of the traditional OXPPP, providing an explanation for its nonessentiality. C. neoformans can utilize gluconate as an alternative carbon source in a GNK1-dependent manner. In our efforts to understand the role of GNK1 in host adaptation and virulence, we found that GNK1-deficient mutants have variable virulence and carbon dioxide tolerance across multiple strains, suggesting that second site mutations frequently interact with GNK1 deletion mutations. In our effort to isolate these genetic loci by backcrossing experiments, we discovered that GNK1-deficient strains are unable to sporulate. These data suggest that gluconate metabolism is critical for sporulation of C. neoformans. IMPORTANCE Cryptococcus neoformans is a fungal pathogen that contributes to nearly 180,000 deaths annually. We characterized a gene named GNK1 that appears to interact with other genetic loci involved with the ability of C. neoformans to act as a pathogen. While these interacting genetic loci remain elusive, we discovered that GNK1 plays roles in both metabolism and mating/sporulation. Further interrogation of the mechanistic role for GNK1 in sexual reproduction may uncover a larger network of genes that are important for host adaptation and virulence.
Collapse
Affiliation(s)
- Andrew J. Jezewski
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Sarah R. Beattie
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Katy M. Alden
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Damian J. Krysan
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
- Microbiology/Immunology, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| |
Collapse
|
12
|
Vélez N, Monteoliva L, Sánchez-Quitian ZA, Amador-García A, García-Rodas R, Ceballos-Garzón A, Gil C, Escandón P, Zaragoza Ó, Parra-Giraldo CM. The Combination of Iron and Copper Increases Pathogenicity and Induces Proteins Related to the Main Virulence Factors in Clinical Isolates of Cryptococcus neoformans var. grubii. J Fungi (Basel) 2022; 8:jof8010057. [PMID: 35049997 PMCID: PMC8778102 DOI: 10.3390/jof8010057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/20/2021] [Accepted: 12/31/2021] [Indexed: 01/09/2023] Open
Abstract
In fungi, metals are associated with the expression of virulence factors. However, it is unclear whether the uptake of metals affects their pathogenicity. This study aimed to evaluate the effect of iron/copper in modulating pathogenicity and proteomic response in two clinical isolates of C. neoformans with high and low pathogenicity. Methods: In both isolates, the effect of 50 µM iron and 500 µM copper on pathogenicity, capsule induction, and melanin production was evaluated. We then performed a quantitative proteomic analysis of cytoplasmic extracts exposed to that combination. Finally, the effect on pathogenicity by iron and copper was evaluated in eight additional isolates. Results: In both isolates, the combination of iron and copper increased pathogenicity, capsule size, and melanin production. Regarding proteomic data, proteins with increased levels after iron and copper exposure were related to biological processes such as cell stress, vesicular traffic (Ap1, Vps35), cell wall structure (Och1, Ccr4, Gsk3), melanin biosynthesis (Hem15, Mln2), DNA repair (Chk1), protein transport (Mms2), SUMOylation (Uba2), and mitochondrial transport (Atm1). Increased pathogenicity by exposure to metal combination was also confirmed in 90% of the eight isolates. Conclusions: The combination of these metals enhances pathogenicity and increases the abundance of proteins related to the main virulence factors.
Collapse
Affiliation(s)
- Nórida Vélez
- Unidad de Proteómica y Micosis Humanas, Grupo de Enfermedades Infecciosas, Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 110231, Colombia; (N.V.); (Z.-A.S.-Q.); (A.C.-G.)
| | - Lucía Monteoliva
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain; (L.M.); (A.A.-G.); (C.G.)
| | - Zilpa-Adriana Sánchez-Quitian
- Unidad de Proteómica y Micosis Humanas, Grupo de Enfermedades Infecciosas, Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 110231, Colombia; (N.V.); (Z.-A.S.-Q.); (A.C.-G.)
| | - Ahinara Amador-García
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain; (L.M.); (A.A.-G.); (C.G.)
| | - Rocío García-Rodas
- Mycology Reference Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III, Carretera Majadahonda-Pozuelo, 28013 Madrid, Spain; (R.G.-R.); (Ó.Z.)
| | - Andrés Ceballos-Garzón
- Unidad de Proteómica y Micosis Humanas, Grupo de Enfermedades Infecciosas, Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 110231, Colombia; (N.V.); (Z.-A.S.-Q.); (A.C.-G.)
- Department of Parasitology and Medical Mycology, Faculty of Pharmacy, University of Nantes, 44200 Nantes, France
| | - Concha Gil
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain; (L.M.); (A.A.-G.); (C.G.)
| | - Patricia Escandón
- Grupo de Microbiología, Instituto Nacional de Salud, Bogotá 111321, Colombia;
| | - Óscar Zaragoza
- Mycology Reference Laboratory, National Centre for Microbiology, Instituto de Salud Carlos III, Carretera Majadahonda-Pozuelo, 28013 Madrid, Spain; (R.G.-R.); (Ó.Z.)
| | - Claudia-Marcela Parra-Giraldo
- Unidad de Proteómica y Micosis Humanas, Grupo de Enfermedades Infecciosas, Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 110231, Colombia; (N.V.); (Z.-A.S.-Q.); (A.C.-G.)
- Correspondence:
| |
Collapse
|
13
|
Li Y, Li H, Sun T, Ding C. Pathogen-Host Interaction Repertoire at Proteome and Posttranslational Modification Levels During Fungal Infections. Front Cell Infect Microbiol 2021; 11:774340. [PMID: 34926320 PMCID: PMC8674643 DOI: 10.3389/fcimb.2021.774340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 11/15/2021] [Indexed: 12/22/2022] Open
Abstract
Prevalence of fungal diseases has increased globally in recent years, which often associated with increased immunocompromised patients, aging populations, and the novel Coronavirus pandemic. Furthermore, due to the limitation of available antifungal agents mortality and morbidity rates of invasion fungal disease remain stubbornly high, and the emergence of multidrug-resistant fungi exacerbates the problem. Fungal pathogenicity and interactions between fungi and host have been the focus of many studies, as a result, lots of pathogenic mechanisms and fungal virulence factors have been identified. Mass spectrometry (MS)-based proteomics is a novel approach to better understand fungal pathogenicities and host–pathogen interactions at protein and protein posttranslational modification (PTM) levels. The approach has successfully elucidated interactions between pathogens and hosts by examining, for example, samples of fungal cells under different conditions, body fluids from infected patients, and exosomes. Many studies conclude that protein and PTM levels in both pathogens and hosts play important roles in progression of fungal diseases. This review summarizes mass spectrometry studies of protein and PTM levels from perspectives of both pathogens and hosts and provides an integrative conceptual outlook on fungal pathogenesis, antifungal agents development, and host–pathogen interactions.
Collapse
Affiliation(s)
- Yanjian Li
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| | - Hailong Li
- NHC Key Laboratory of AIDS Immunology (China Medical University), National Clinical Research Center for Laboratory Medicine, The First Affiliated Hospital of China Medical University, Shenyang, China
| | - Tianshu Sun
- Medical Research Centre, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, China.,Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - Chen Ding
- College of Life and Health Sciences, Northeastern University, Shenyang, China
| |
Collapse
|
14
|
Rezende CP, Brito PKMO, Da Silva TA, Pessoni AM, Ramalho LNZ, Almeida F. Influence of Galectin-3 on the Innate Immune Response during Experimental Cryptococcosis. J Fungi (Basel) 2021; 7:jof7060492. [PMID: 34203011 PMCID: PMC8234158 DOI: 10.3390/jof7060492] [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: 05/11/2021] [Revised: 06/11/2021] [Accepted: 06/16/2021] [Indexed: 11/16/2022] Open
Abstract
Cryptococcus neoformans, the causative agent of cryptococcosis, is the primary fungal pathogen that affects the immunocompromised individuals. Galectin-3 (Gal-3) is an animal lectin involved in both innate and adaptive immune responses. The present study aimed to evaluate the influence of Gal-3 on the C. neoformans infection. We performed histopathological and gene profile analysis of the innate antifungal immunity markers in the lungs, spleen, and brain of the wild-type (WT) and Gal-3 knockout (KO) mice during cryptococcosis. These findings suggest that Gal-3 absence does not cause significant histopathological alterations in the analyzed tissues. The expression profile of the genes related to innate antifungal immunity showed that the presence of cryptococcosis in the WT and Gal-3 KO animals, compared to their respective controls, promoted the upregulation of the pattern recognition receptor (PRR) responsive to mannose/chitin (mrc1) and a gene involved in inflammation (ccr5), as well as the downregulation of the genes related to signal transduction (card9, fos, ikbkb, jun) and PRRs (cd209a, colec12, nptx1). The absence of Gal-3, in fungal infection, a positively modulated gene involved in phagocytosis (sftpd) and negatively genes involved in signal transduction (syk and myd88), proinflammatory cytokines il-1β and il-12b and cd209a receptor. Therefore, our results suggest that Gal-3 may play an essential role in the development of antifungal immune responses against cryptococcosis.
Collapse
Affiliation(s)
- Caroline Patini Rezende
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto 14049-900, SP, Brazil; (C.P.R.); (A.M.P.)
| | - Patricia Kellen Martins Oliveira Brito
- Department of Cellular and Molecular Biology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto 14049-900, SP, Brazil; (P.K.M.O.B.); (T.A.D.S.)
| | - Thiago Aparecido Da Silva
- Department of Cellular and Molecular Biology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto 14049-900, SP, Brazil; (P.K.M.O.B.); (T.A.D.S.)
| | - Andre Moreira Pessoni
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto 14049-900, SP, Brazil; (C.P.R.); (A.M.P.)
| | | | - Fausto Almeida
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto 14049-900, SP, Brazil; (C.P.R.); (A.M.P.)
- Correspondence:
| |
Collapse
|
15
|
Ueno K, Otani Y, Yanagihara N, Urai M, Nagamori A, Sato-Fukushima M, Shimizu K, Saito N, Miyazaki Y. Cryptococcus gattii evades CD11b-mediated fungal recognition by coating itself with capsular polysaccharides. Eur J Immunol 2021; 51:2281-2295. [PMID: 33728652 DOI: 10.1002/eji.202049042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 01/25/2021] [Accepted: 03/10/2021] [Indexed: 12/15/2022]
Abstract
Cryptococcus gattii is a capsular pathogenic fungus causing life-threatening cryptococcosis. Although the capsular polysaccharides (CPs) of C. gattii are considered as virulence factors, the physiological significance of CP biosynthesis and of CPs themselves is not fully understood, with many conflicting data reported. First, we demonstrated that CAP gene deletant of C. gattii completely lacked capsule layer and its virulence, and that the strain was susceptible to host-related factors including oxidizing, hypoxic, and hypotrophic conditions in vitro. Extracellular CPs recovered from culture supernatant bound specifically to C. gattii acapsular strains, not to other fungi and immune cells, and rendered them the immune escape effects. In fact, dendritic cells (DCs) did not efficiently uptake the CP-treated acapsular strains, which possessed no visible capsule layer, and a decreased amount of phosphorylated proteins and cytokine levels after the stimulation. DCs recognized C. gattii acapuslar cells via an immune receptor CD11b- and Syk-related pathway; however, CD11b did not bind to CP-treated acapsular cells. These results suggested that CPs support immune evasion by coating antigens on C. gattii and blocking the interaction between CD11b and C. gattii cells. Here, we describe the importance of CPs in pathogenicity and immune evasion mechanisms of C. gattii.
Collapse
Affiliation(s)
- Keigo Ueno
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Yoshiko Otani
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan.,Department of Biological Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Katsushika-ku, Tokyo, Japan
| | - Nao Yanagihara
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan.,Department of Biological Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Katsushika-ku, Tokyo, Japan
| | - Makoto Urai
- Department of Chemistry for Life Sciences and Agriculture, Faculty of Life Sciences, Tokyo University of Agriculture, Setagaya-ku, Tokyo, Japan
| | - Akiko Nagamori
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Miyuki Sato-Fukushima
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Kiminori Shimizu
- Department of Biological Science and Technology, Faculty of Industrial Science and Technology, Tokyo University of Science, Katsushika-ku, Tokyo, Japan
| | - Noriko Saito
- Laboratory of Electron Microscopy, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| | - Yoshitsugu Miyazaki
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan
| |
Collapse
|
16
|
Huang YM, Tao XH, Xu DF, Yu Y, Teng Y, Xie WQ, Fan YB. HOG1 has an essential role in the stress response, virulence and pathogenicity of Cryptococcus gattii. Exp Ther Med 2021; 21:476. [PMID: 33767771 PMCID: PMC7976431 DOI: 10.3892/etm.2021.9907] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 02/05/2021] [Indexed: 12/25/2022] Open
Abstract
Cryptococcus gattii (C. gattii) is a lethal pathogen that causes the majority of cryptococcosis cases in previously healthy individuals. This pathogen poses an increasing threat to global public health, but the mechanisms underlying the pathogenesis have remained to be fully elucidated. In the present study, the role of high-osmolarity glycerol (HOG)1 in the stress reaction and virulence control of C. gattii was characterized by deleting the HOG1 gene using the clinical isolate strain CZ2012, and finally, the virulence and pathogenic traits of the deletion strain were defined. Deletion of the HOG1 gene resulted in notable growth defects under stress conditions (high salt and antifungal drugs), but different traits were observed under oxidative stress conditions (hydrogen peroxide). Similarly, the C. gattii hog1Δ strains (deletion of HOG1) also displayed decreased capsule production and melanin synthesis. Furthermore, mice infected with the hog1Δ strain had longer survival times than those infected with the wild-type strain and the reconstituted strain. The hog1Δ strain recovered from infected organs exhibited significant growth defects in terms of decreased colony count and size. The present results suggested that HOG1 has a significant role in the virulence of C. gattii and these results may help to elucidate the pathogenesis of C. gattii.
Collapse
Affiliation(s)
- You-Ming Huang
- Department of Dermatology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Xiao-Hua Tao
- Department of Dermatology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Dan-Feng Xu
- Department of Dermatology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Yong Yu
- Department of Dermatology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Yan Teng
- Department of Dermatology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| | - Wen-Qing Xie
- Department of Orthopedics, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410000, P.R. China
| | - Yi-Bin Fan
- Department of Dermatology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, Zhejiang 310014, P.R. China
| |
Collapse
|
17
|
Sun T, Li X, Song W, Yu S, Wang L, Ding C, Xu Y. Metabolomic alterations associated with copper stress in Cryptococcus neoformans. Future Microbiol 2021; 16:305-316. [PMID: 33635120 DOI: 10.2217/fmb-2020-0290] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Background: Copper stress is an effective host strategy in resisting the opportunistic pathogenic fungus Cryptococcus neoformans. We studied metabolic changes in C. neoformans under copper stress. Materials & methods: Wild-type and metallothionein-null C. neoformans were treated with copper on agar containing glucose, glycerol or ethanol as the carbon source and their metabolites were analyzed by untarget metabolomics strategy using gas chromatography coupled with time-of-flight mass spectrometry. Results: The metabolic profile of C. neoformans varied in the presence and absence of copper. Pathway enrichment analysis showed that the differentially abundant metabolites were related to amino acid and carbohydrate metabolism. C. neoformans grown on glycerol or ethanol resisted copper toxicity better than C. neoformans grown on glucose. Conclusion: Copper stress alters the metabolic profile of C. neoformans.
Collapse
Affiliation(s)
- Tianshu Sun
- Medical Research Center, State Key Laboratory of Complex Severe & Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China.,Beijing Key Laboratory for Mechanisms Research & Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - Xiaogang Li
- Medical Research Center, State Key Laboratory of Complex Severe & Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China.,Beijing Key Laboratory for Mechanisms Research & Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - Wei Song
- Medical Research Center, State Key Laboratory of Complex Severe & Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China
| | - Shuying Yu
- Department of Clinical Laboratory, State Key Laboratory of Complex Severe & Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China.,Beijing Key Laboratory for Mechanisms Research & Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - Linqi Wang
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Chen Ding
- College of Life & Health Sciences, Northeastern University, Shenyang, China
| | - Yingchun Xu
- Department of Clinical Laboratory, State Key Laboratory of Complex Severe & Rare Diseases, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Sciences, Beijing, China.,Beijing Key Laboratory for Mechanisms Research & Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| |
Collapse
|
18
|
Araújo GRDS, Alves V, Martins-de-Souza PH, Guimarães AJ, Honorato L, Nimrichter L, Takiya CM, Pontes B, Frases S. Dexamethasone and Methylprednisolone Promote Cell Proliferation, Capsule Enlargement, and in vivo Dissemination of C. neoformans. FRONTIERS IN FUNGAL BIOLOGY 2021; 2:643537. [PMID: 37744119 PMCID: PMC10512211 DOI: 10.3389/ffunb.2021.643537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 01/19/2021] [Indexed: 09/26/2023]
Abstract
Cryptococcus neoformans is a fungal pathogen that causes life-threatening infections in immunocompromised individuals, who often have some inflammatory condition and, therefore, end up using glucocorticoids, such as dexamethasone and methylprednisolone. Although the effects of this class of molecules during cryptococcosis have been investigated, their consequences for the biology of C. neoformans is less explored. Here, we studied the effects of dexamethasone and methylprednisolone on the metabolism and on the induction of virulence factors in C. neoformans. Our results showed that both glucocorticoids increased fungal cell proliferation and surface electronegativity but reduced capsule and secreted polysaccharide sizes, as well as capsule compaction, by decreasing the density of polysaccharide fibers. We also tested whether glucocorticoids could affect the fungal virulence in Galleria mellonella and mice. Although the survival rate of Galleria larvae increased, those from mice showed a tendency to decrease, with infected animals dying earlier after glucocorticoid treatments. The pathogenesis of spread of cryptococcosis and the interleukin secretion pattern were also assessed for lungs and brains of infected mice. While increases in the spread of the fungus to lungs were observed after treatment with glucocorticoids, a significant difference in brain was observed only for methylprednisolone, although a trend toward increasing was also observed for dexamethasone. Moreover, increases in both pulmonary and cerebral IL-10 production, reduction of IL-6 production but no changes in IL-4, IL-17, and INF-γ were also observed after glucocorticoid treatments. Finally, histopathological analysis confirmed the increase in number of fungal cells in lung and brain tissues of mice previously subjected to dexamethasone or methylprednisolone treatments. Together, our results provide compelling evidence for the effects of dexamethasone and methylprednisolone on the biology of C. neoformans and may have important implications for future clinical treatments, calling attention to the risks of using these glucocorticoids against cryptococcosis or in immunocompromised individuals.
Collapse
Affiliation(s)
- Glauber R. de S. Araújo
- Laboratório de Ultraestrutura Cellular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Vinicius Alves
- Laboratório de Ultraestrutura Cellular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Pedro H. Martins-de-Souza
- Laboratório de Ultraestrutura Cellular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Allan J. Guimarães
- Laboratório de Bioquímica e Imunologia das Micoses, Depto. de Microbiologia e Parasitologia, Instituto Biomédico, Universidade Federal Fluminense, Niterói, Brazil
| | - Leandro Honorato
- Instituto de Microbiologia Paulo de Góes, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Leonardo Nimrichter
- Instituto de Microbiologia Paulo de Góes, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Christina Maeda Takiya
- Laboratório de Imunopatologia. Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Bruno Pontes
- Instituto de Ciências Biomédicas, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
- Centro Nacional de Biologia Estrutural e Bioimagem (CENABIO), Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Susana Frases
- Laboratório de Ultraestrutura Cellular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil
| |
Collapse
|
19
|
Retanal C, Ball B, Geddes-McAlister J. Post-Translational Modifications Drive Success and Failure of Fungal-Host Interactions. J Fungi (Basel) 2021; 7:jof7020124. [PMID: 33572187 PMCID: PMC7914884 DOI: 10.3390/jof7020124] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/04/2021] [Accepted: 02/08/2021] [Indexed: 12/11/2022] Open
Abstract
Post-translational modifications (PTMs) change the structure and function of proteins and regulate a diverse array of biological processes. Fungal pathogens rely on PTMs to modulate protein production and activity during infection, manipulate the host response, and ultimately, promote fungal survival. Given the high mortality rates of fungal infections on a global scale, along with the emergence of antifungal-resistant species, identifying new treatment options is critical. In this review, we focus on the role of PTMs (e.g., phosphorylation, acetylation, ubiquitination, glycosylation, and methylation) among the highly prevalent and medically relevant fungal pathogens, Candida spp., Aspergillus spp., and Cryptococcus spp. We explore the role of PTMs in fungal stress response and host adaptation, the use of PTMs to manipulate host cells and the immune system upon fungal invasion, and the importance of PTMs in conferring antifungal resistance. We also provide a critical view on the current knowledgebase, pose questions key to our understanding of the intricate roles of PTMs within fungal pathogens, and provide research opportunities to uncover new therapeutic strategies.
Collapse
|
20
|
Pirofski LA, Casadevall A. The state of latency in microbial pathogenesis. J Clin Invest 2021; 130:4525-4531. [PMID: 32804154 DOI: 10.1172/jci136221] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The state of latency occurs when a microbe's persistence in a host produces host damage without perturbing homeostasis sufficiently to cause clinical symptoms or disease. The mechanisms contributing to latency are diverse and depend on the nature of both the microbe and the host. Latency has advantages for both host and microbe. The host avoids progressive damage caused by interaction with the microbe that may translate into disease, and the microbe secures a stable niche in which to survive. Latency is clinically important because some latent microbes can be transmitted to other hosts, and it is associated with a risk for recrudescent microbial growth and development of disease. In addition, it can predispose the host to other diseases, such as malignancies. Hence, latency is a temporally unstable state with an eventual outcome that mainly depends on host immunity. Latency is an integral part of the pathogenic strategies of microbes that require human (and/or mammalian) hosts, including herpesviruses, retroviruses, Mycobacterium tuberculosis, and Toxoplasma gondii. However, latency is also an outcome of infection with environmental organisms such as Cryptococcus neoformans, which require no host in their replicative cycles. For most microbes that achieve latency, there is a need for a better understanding and more investigation of host and microbial mechanisms that result in this state.
Collapse
Affiliation(s)
- Liise-Anne Pirofski
- Division of Infectious Diseases, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, USA
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins School of Public Health, Baltimore, Maryland, USA
| |
Collapse
|
21
|
Zhao J, Yang Y, Fan Y, Yi J, Zhang C, Gu Z, Pan W, Gu J, Liao W, Fang W. Ribosomal Protein L40e Fused With a Ubiquitin Moiety Is Essential for the Vegetative Growth, Morphological Homeostasis, Cell Cycle Progression, and Pathogenicity of Cryptococcus neoformans. Front Microbiol 2020; 11:570269. [PMID: 33224112 PMCID: PMC7674629 DOI: 10.3389/fmicb.2020.570269] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 08/20/2020] [Indexed: 11/13/2022] Open
Abstract
Ubiquitin is a highly conserved protein required for various fundamental cellular processes in eukaryotes. Herein, we first report the contribution of the ubiquitin fusion protein Ubi1 (a ubiquitin monomer fused with the ribosome protein L40e, Rpl40e) in the growth and pathogenicity of Cryptococcus neoformans. UBI1 deletion resulted in severe growth restriction of C. neoformans, whose growth rate was positively correlated with UBI1 expression level. The growth defect of the ubi1Δ strain could be closely associated with its morphological abnormalities, such as its reduced ribosome particles. In addition, the ubi1Δ mutant also displayed increased cell ploidy, cell cycle arrest, and decreased intracellular survival inside macrophages. All these phenotypes were reversed by the reconstitution of the full-length UBI1 gene or RPL40a domain. Mouse survival and fungal burden assays further revealed a severely attenuated pathogenicity for the ubi1Δ mutant, which is probably associated with its reduced stress tolerance and the induction of T-helper 1-type immune response. Taken together, Ubi1 is required for maintaining the vegetative growth, morphological homeostasis, cell cycle progression, and pathogenicity in vivo of C. neoformans. The pleiotropic roles of Ubi1 are dependent on the presence of Rpl40e and associated with its regulation of cryptococcal ribosome biogenesis.
Collapse
Affiliation(s)
- Jingyu Zhao
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Second Military Medical University, Shanghai, China.,Department of Dermatology, Shanghai Eastern Hepatobiliary Surgery Hospital, Shanghai, China
| | - Yali Yang
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Second Military Medical University, Shanghai, China.,Department of Dermatology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yibin Fan
- Department of Dermatology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, China
| | - Jiu Yi
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Chao Zhang
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Zhongkai Gu
- The Institute of Biomedical Sciences, Fudan University, Shanghai, China
| | - Weihua Pan
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Julin Gu
- Department of Dermatology, Shanghai Eastern Hepatobiliary Surgery Hospital, Shanghai, China
| | - Wanqing Liao
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Wei Fang
- Shanghai Key Laboratory of Molecular Medical Mycology, Department of Dermatology, Changzheng Hospital, Second Military Medical University, Shanghai, China
| |
Collapse
|
22
|
Thanh LT, Toffaletti DL, Tenor JL, Giamberardino C, Sempowski GD, Asfaw Y, Phan HT, Van Duong A, Trinh NM, Thwaites GE, Ashton PM, Chau NVV, Baker SG, Perfect JR, Day JN. Assessing the virulence of Cryptococcus neoformans causing meningitis in HIV infected and uninfected patients in Vietnam. Med Mycol 2020; 58:1149-1161. [PMID: 32196550 PMCID: PMC7657091 DOI: 10.1093/mmy/myaa013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/14/2020] [Accepted: 02/25/2020] [Indexed: 12/17/2022] Open
Abstract
We previously observed a substantial burden of cryptococcal meningitis in Vietnam atypically arising in individuals who are uninfected with human immunodeficiency virus (HIV). This disease was associated with a single genotype of Cryptococcus neoformans (sequence type [ST]5), which was significantly less common in HIV-infected individuals. Aiming to compare the phenotypic characteristics of ST5 and non-ST5 C. neoformans, we selected 30 representative Vietnamese isolates and compared their in vitro pathogenic potential and in vivo virulence. ST5 and non-ST5 organisms exhibited comparable characteristics with respect to in vitro virulence markers including melanin production, replication at 37°C, and growth in cerebrospinal fluid. However, the ST5 isolates had significantly increased variability in cellular and capsular sizing compared with non-ST5 organisms (P < .001). Counterintuitively, mice infected with ST5 isolates had significantly longer survival with lower fungal burdens at day 7 than non-ST5 isolates. Notably, ST5 isolates induced significantly greater initial inflammatory responses than non-ST5 strains, measured by TNF-α concentrations (P < .001). Despite being generally less virulent in the mouse model, we hypothesize that the significant within strain variation seen in ST5 isolates in the tested phenotypes may represent an evolutionary advantage enabling adaptation to novel niches including apparently immunocompetent human hosts.
Collapse
Affiliation(s)
- Lam Tuan Thanh
- Oxford University Clinical Research Unit, Wellcome Trust Asia Africa Programme, Ho Chi Minh City, Vietnam
| | - Dena L Toffaletti
- Division of Infectious Diseases, Department of Medicine and Department of Molecular Genetics and Microbiology, Duke University, North Carolina, USA
| | - Jennifer L Tenor
- Division of Infectious Diseases, Department of Medicine and Department of Molecular Genetics and Microbiology, Duke University, North Carolina, USA
| | - Charles Giamberardino
- Division of Infectious Diseases, Department of Medicine and Department of Molecular Genetics and Microbiology, Duke University, North Carolina, USA
| | - Gregory D Sempowski
- Duke Human Vaccine Institute and Regional Biocontainment Laboratory, Duke University, North Carolina, USA
| | - Yohannes Asfaw
- Division of Laboratory Animal Resources, Duke University, North Carolina, USA
| | - Hai Trieu Phan
- Oxford University Clinical Research Unit, Wellcome Trust Asia Africa Programme, Ho Chi Minh City, Vietnam
| | - Anh Van Duong
- Oxford University Clinical Research Unit, Wellcome Trust Asia Africa Programme, Ho Chi Minh City, Vietnam
| | - Nguyen Mai Trinh
- Oxford University Clinical Research Unit, Wellcome Trust Asia Africa Programme, Ho Chi Minh City, Vietnam
| | - Guy E Thwaites
- Oxford University Clinical Research Unit, Wellcome Trust Asia Africa Programme, Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Philip M Ashton
- Oxford University Clinical Research Unit, Wellcome Trust Asia Africa Programme, Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | | | - Stephen G Baker
- Cambridge Institute of Therapeutic immunology and Infectious Disease, Department of Medicine, University of Cambridge, Cambridge, UK
| | - John R Perfect
- Division of Infectious Diseases, Department of Medicine and Department of Molecular Genetics and Microbiology, Duke University, North Carolina, USA
| | - Jeremy N Day
- Oxford University Clinical Research Unit, Wellcome Trust Asia Africa Programme, Ho Chi Minh City, Vietnam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| |
Collapse
|
23
|
Yu CH, Chen Y, Desjardins CA, Tenor JL, Toffaletti DL, Giamberardino C, Litvintseva A, Perfect JR, Cuomo CA. Landscape of gene expression variation of natural isolates of Cryptococcus neoformans in response to biologically relevant stresses. Microb Genom 2020; 6. [PMID: 31860441 PMCID: PMC7067042 DOI: 10.1099/mgen.0.000319] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen that at its peak epidemic levels caused an estimated million cases of cryptococcal meningitis per year worldwide. This species can grow in diverse environmental (trees, soil and bird excreta) and host niches (intracellular microenvironments of phagocytes and free-living in host tissues). The genetic basic for adaptation to these different conditions is not well characterized, as most experimental work has relied on a single reference strain of C. neoformans. To identify genes important for yeast infection and disease progression, we profiled the gene expression of seven C. neoformans isolates grown in five representative in vitro environmental and in vivo conditions. We characterized gene expression differences using RNA-Seq (RNA sequencing), comparing clinical and environmental isolates from two of the major lineages of this species, VNI and VNBI. These comparisons highlighted genes showing lineage-specific expression that are enriched in subtelomeric regions and in lineage-specific gene clusters. By contrast, we find few expression differences between clinical and environmental isolates from the same lineage. Gene expression specific to in vivo stages reflects available nutrients and stresses, with an increase in fungal metabolism within macrophages, and an induction of ribosomal and heat-shock gene expression within the subarachnoid space. This study provides the widest view to date of the transcriptome variation of C. neoformans across natural isolates, and provides insights into genes important for in vitro and in vivo growth stages.
Collapse
Affiliation(s)
- Chen-Hsin Yu
- Division of Infectious Diseases, Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
| | - Yuan Chen
- Division of Infectious Diseases, Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
| | | | - Jennifer L Tenor
- Division of Infectious Diseases, Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
| | - Dena L Toffaletti
- Division of Infectious Diseases, Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
| | - Charles Giamberardino
- Division of Infectious Diseases, Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
| | - Anastasia Litvintseva
- Mycotic Diseases Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30329, USA
| | - John R Perfect
- Division of Infectious Diseases, Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
| | | |
Collapse
|
24
|
A Transcriptional Regulatory Map of Iron Homeostasis Reveals a New Control Circuit for Capsule Formation in Cryptococcus neoformans. Genetics 2020; 215:1171-1189. [PMID: 32580959 DOI: 10.1534/genetics.120.303270] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 06/18/2020] [Indexed: 11/18/2022] Open
Abstract
Iron is essential for the growth of the human fungal pathogen Cryptococcus neoformans within the vertebrate host, and iron sensing contributes to the elaboration of key virulence factors, including the formation of the polysaccharide capsule. C. neoformans employs sophisticated iron acquisition and utilization systems governed by the transcription factors Cir1 and HapX. However, the details of the transcriptional regulatory networks that are governed by these transcription factors and connections to virulence remain to be defined. Here, we used chromatin immunoprecipitation followed by next-generation sequencing (ChIP-seq) and transcriptome analysis (RNA-seq) to identify genes directly regulated by Cir1 and/or HapX in response to iron availability. Overall, 40 and 100 genes were directly regulated by Cir1, and 171 and 12 genes were directly regulated by HapX, under iron-limited and replete conditions, respectively. More specifically, we found that Cir1 directly controls the expression of genes required for iron acquisition and metabolism, and indirectly governs capsule formation by regulating specific protein kinases, a regulatory connection not previously revealed. HapX regulates the genes responsible for iron-dependent pathways, particularly under iron-depleted conditions. By analyzing target genes directly bound by Cir1 and HapX, we predicted the binding motifs for the transcription factors and verified that the purified proteins bind these motifs in vitro Furthermore, several direct target genes were coordinately and reciprocally regulated by Cir1 and HapX, suggesting that these transcription factors play conserved roles in the response to iron availability. In addition, biochemical analyses revealed that Cir1 and HapX are iron-containing proteins, implying that the regulatory networks of Cir1 and HapX may be influenced by the incorporation of iron into these proteins. Taken together, our identification of the genome-wide transcriptional networks provides a detailed understanding of the iron-related regulatory landscape, establishes a new connection between Cir1 and kinases that regulate capsule, and underpins genetic and biochemical analyses that reveal iron-sensing mechanisms for Cir1 and HapX in C. neoformans.
Collapse
|
25
|
Abstract
Among fungal pathogens, Cryptococcus neoformans has gained great importance among the scientific community of several reasons. This fungus is the causative agent of cryptococcosis, a disease mainly associated to HIV immunosuppression and characterized by the appearance of meningoencephalitis. Cryptococcal meningitis is responsible for hundreds of thousands of deaths every year. Research of the pathogenesis and virulence mechanisms of this pathogen has focused on three main different areas: Adaptation to the host environment (nutrients, pH, and free radicals), mechanism of immune evasion (which include phenotypic variations and the ability to behave as a facultative intracellular pathogen), and production of virulence factors. Cryptococcus neoformans has two phenotypic characteristics, the capsule and synthesis of melanin that have a profound effect in the virulence of the yeast because they both have protective effects and induce host damage as virulence factors. Finally, the mechanisms that result in dissemination and brain invasion are also of key importance to understand cryptococcal disease. In this review, I will provide a brief overview of the main mechanisms that makes C. neoformans a pathogen in susceptible patients. Abbreviations: RNS: reactive nitrogen species; BBB: brain blood barrier; GXM: glucuronoxylomannan; GXMGal: glucuronoxylomannogalactan
Collapse
Affiliation(s)
- Oscar Zaragoza
- a Mycology Reference Laboratory National Centre for Microbiology , Instituto de Salud Carlos III Carretera Majadahonda-Pozuelo , Madrid , Spain
| |
Collapse
|
26
|
Abstract
We herein report a 76-year-old Japanese man with myelofibrosis who developed cryptococcal meningitis. After treatment for 5 months with ruxolitinib, the patient presented with fever and disturbance of consciousness. Marked nuchal stiffness was noted. The magnetic resonance imaging results of the brain were normal. Lumbar puncture showed an opening cerebrospinal fluid (CSF) pressure of 110 mm H2O, pleocytosis (85 mononuclear cells and 222 polymorphonuclear cells/μL), decreased CSF/serum glucose ratio (43%), and elevated protein (194 mg/dL). Blood and CSF cultures grew no bacteria or fungi. However, cryptococcal antigen was detected in the blood and CSF samples. We discontinued ruxolitinib and started administration of amphotericin B. His condition improved gradually 1 week after initiation of treatment. There have been only a few reports on cryptococcal meningitis associated with ruxolitinib. Physicians should consider the possibility of cryptococcal meningitis in patients receiving ruxolitinib.
Collapse
|
27
|
Martho KF, Brustolini OJB, Vasconcelos AT, Vallim MA, Pascon RC. The Glycerol Phosphatase Gpp2: A Link to Osmotic Stress, Sulfur Assimilation and Virulence in Cryptococcus neoformans. Front Microbiol 2019; 10:2728. [PMID: 31849880 PMCID: PMC6901960 DOI: 10.3389/fmicb.2019.02728] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 11/08/2019] [Indexed: 12/13/2022] Open
Abstract
Cryptococcus neoformans is an opportunist fungal pathogen that causes meningoencephalitis in immunocompromised patients. During infection, this basidiomycete yeast has to adapt to several adverse conditions, especially nutrient availability. The interruption on various amino acid biosynthetic pathways and on amino acid uptake causes reduced viability, inability to cope with various stresses, failure in virulence factors expression and avirulence in animal model of infection. The sulfur amino acid biosynthesis and uptake is an important feature for pathogen survival in vivo and in vitro. Our previous work demonstrates that C. neoformans Cys3 BZip transcription factor controls the gene expression in several steps of the sulfur assimilation and sulfur amino acid biosynthesis. Also, we have shown that Gpp2 phosphatase modulates Cys3 activity. In Saccharomyces cerevisiae Gpp2 is induced in response to hyper osmotic or oxidative stress and during diauxic shift. In this work, we will show that, in C. neoformans, Gpp2 is required to respond to stresses, mainly osmotic stress; also its transcription is induced during exposure to NaCl. Global transcriptional profile of gpp2Δ by RNAseq shows that CYS3 and other genes in the sulfur assimilation pathway are up regulated, which is consistent with our previous report, in which Gpp2 acts by avoiding Cys3 accumulation and nuclear localization. In addition, several transporters genes, especially amino acid permeases and oxidative stress genes are induced in the gpp2Δ strain; on the contrary, genes involved in glucose and tricarboxylic acid metabolism are down regulated. gpp2Δ strain fails to express virulence factors, as melanin, phospholipase, urease and has virulence attenuation in Galleria mellonella. Our data suggest that Gpp2 is an important factor for general pathogen adaptation to various stresses and also to the host, and perhaps it could be an interesting target for therapeutic use.
Collapse
Affiliation(s)
- Kevin Felipe Martho
- Department of Biological Sciences, Campus Diadema, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Otávio J B Brustolini
- Laboratório Nacional de Computação Científica - LNCC, Labinfo - Laboratório de Bioinformática, Petrópolis, Brazil
| | - Ana Tereza Vasconcelos
- Laboratório Nacional de Computação Científica - LNCC, Labinfo - Laboratório de Bioinformática, Petrópolis, Brazil
| | - Marcelo A Vallim
- Department of Biological Sciences, Campus Diadema, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Renata C Pascon
- Department of Biological Sciences, Campus Diadema, Universidade Federal de São Paulo, São Paulo, Brazil
| |
Collapse
|
28
|
Du W, Li H, Tian B, Sai S, Gao Y, Lan T, Meng Y, Ding C. Development of nose-to-brain delivery of ketoconazole by nanostructured lipid carriers against cryptococcal meningoencephalitis in mice. Colloids Surf B Biointerfaces 2019; 183:110446. [PMID: 31465938 DOI: 10.1016/j.colsurfb.2019.110446] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 07/25/2019] [Accepted: 08/18/2019] [Indexed: 11/26/2022]
Abstract
Cryptococcus neoformans-mediated meningoencephalitis is a critical infectious disorder of the human central nervous system. However, efficient treatment for the disease is limited due to the poor penetration across the blood brain barrier (BBB). Here, we develop a nose-to-brain drug delivery system utilizing nanostructured lipid carriers (NLCs). We demonstrated that fluorescent-dye-loaded NLCs efficiently uptake into the cytoplasm of encapsulated C. neoformans cells. In comparison with current antifungal drugs, the ketoconazole (keto)-NLCs show significantly increased antifungal activity against C. neoformans in vivo under various growth conditions. The NLCs show enhanced tissue colonization properties. Importantly, using animal imaging analyses, NLCs are able to enter brain tissues via the olfactory bulb region by intranasal administration, bypassing the BBB. In addition, NLCs maintain prolonged residence in tissues. In mouse brain tissue, keto-NLCs showed significantly enhanced antifungal activity when administered intranasally, drastically dampening the C. neoformans burden. Taken together, NLCs not only improve the ketoconazole penetration efficiency against capsulated C. neoformans cells, but also boost the efficacy of antifungal drugs. Most importantly, keto-NLCs significantly contribute to the treatment of cryptococcal meningoencephalitis in mice by bypassing the BBB via the olfactory system.
Collapse
Affiliation(s)
- Wei Du
- College of Life and Health Sciences, Northeastern University, Shenyang, Liaoning 110015, China
| | - Hailong Li
- College of Life and Health Sciences, Northeastern University, Shenyang, Liaoning 110015, China
| | - Baocheng Tian
- School of Medicine, Binzhou Medical University, Yantai, China
| | - Sixiang Sai
- School of Medicine, Binzhou Medical University, Yantai, China
| | - Yiru Gao
- College of Life and Health Sciences, Northeastern University, Shenyang, Liaoning 110015, China
| | - Tian Lan
- College of Life and Health Sciences, Northeastern University, Shenyang, Liaoning 110015, China
| | - Yang Meng
- College of Life and Health Sciences, Northeastern University, Shenyang, Liaoning 110015, China
| | - Chen Ding
- College of Life and Health Sciences, Northeastern University, Shenyang, Liaoning 110015, China.
| |
Collapse
|
29
|
The regulation of the sulfur amino acid biosynthetic pathway in Cryptococcus neoformans: the relationship of Cys3, Calcineurin, and Gpp2 phosphatases. Sci Rep 2019; 9:11923. [PMID: 31417135 PMCID: PMC6695392 DOI: 10.1038/s41598-019-48433-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 08/01/2019] [Indexed: 01/02/2023] Open
Abstract
Cryptococcosis is a fungal disease caused by C. neoformans. To adapt and survive in diverse ecological niches, including the animal host, this opportunistic pathogen relies on its ability to uptake nutrients, such as carbon, nitrogen, iron, phosphate, sulfur, and amino acids. Genetic circuits play a role in the response to environmental changes, modulating gene expression and adjusting the microbial metabolism to the nutrients available for the best energy usage and survival. We studied the sulfur amino acid biosynthesis and its implications on C. neoformans biology and virulence. CNAG_04798 encodes a BZip protein and was annotated as CYS3, which has been considered an essential gene. However, we demonstrated that CYS3 is not essential, in fact, its knockout led to sulfur amino acids auxotroph. Western blots and fluorescence microscopy indicated that GFP-Cys3, which is expressed from a constitutive promoter, localizes to the nucleus in rich medium (YEPD); the addition of methionine and cysteine as sole nitrogen source (SD-N + Met/Cys) led to reduced nuclear localization and protein degradation. By proteomics, we identified and confirmed physical interaction among Gpp2, Cna1, Cnb1 and GFP-Cys3. Deletion of the calcineurin and GPP2 genes in a GFP-Cys3 background demonstrated that calcineurin is required to maintain Cys3 high protein levels in YEPD and that deletion of GPP2 causes GFP-Cys3 to persist in the presence of sulfur amino acids. Global transcriptional profile of mutant and wild type by RNAseq revealed that Cys3 controls all branches of the sulfur amino acid biosynthesis, and sulfur starvation leads to induction of several amino acid biosynthetic routes. In addition, we found that Cys3 is required for virulence in Galleria mellonella animal model.
Collapse
|
30
|
Unveil the transcriptional landscape at the Cryptococcus-host axis in mice and nonhuman primates. PLoS Negl Trop Dis 2019; 13:e0007566. [PMID: 31329596 PMCID: PMC6675133 DOI: 10.1371/journal.pntd.0007566] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 08/01/2019] [Accepted: 06/20/2019] [Indexed: 12/17/2022] Open
Abstract
Pathogens and hosts require rapid modulation of virulence and defense mechanisms at the infection axis, but monitoring such modulations is challenging. In studying the human fungal pathogen Cryptococcus neoformans, mouse and rabbit infection models are often employed to shed light on the disease mechanisms but that may not be clinically relevant. In this study, we developed an animal infection model using the non-human primate cynomolgus monkey Macaca fascicularis. In addition, we systematically profiled and compared transcriptional responses between the infected mice and the cynomolgus monkey, using simultaneous or dual RNA next-generation sequencing. We demonstrated that there are shared but distinct transcriptional profiles between the two models following C. neoformans infection. Specifically, genes involved in immune and inflammatory responses are all upregulated. Osteoclastogenesis and insulin signaling are also significantly co-regulated in both models and disrupting an osteoclastogenesis-associated gene (OC-STAMP) or the insulin-signaling process significantly altered the host tolerance to C. neoformans. Moreover, C. neoformans was shown to activate metal sequestration, dampen the sugar metabolism, and control cell morphology during infection. Taking together, we described the development of a non-human primate model of cryptococcosis that allowed us to perform an in-depth analysis and comparison of transcriptome profiles during infections of two animal models and conceptually identify host genes important in disease responses. This study provides new insights in understanding fungal pathogenesis mechanisms that potentially facilitate the identification of novel drug targets for the treatment of cryptococcal infection. The host-pathogen interaction is highly dynamic and tightly regulated, and yet is difficult to monitor. Traditional investigations provide valuable information for the understanding of pathogenic microbial biology but are time-consuming and often neglect the host immune responses. In addition, current animal models for studying pathogenic fungi are limited in mimicking the responses from humans. The development of a new Cryptococcus neoformans infection model using nonhuman primates and the utilization of simultaneous RNA sequencing analysis provide fast and clinically relevant research data allowing the identification of novel critical players from both the invading fungus and the host. The data from the current study would not only help to decipher disease mechanisms but also promote the discovery of novel antifungal drug targets.
Collapse
|
31
|
Role of Amino Acid Metabolism in the Virulence of Human Pathogenic Fungi. CURRENT CLINICAL MICROBIOLOGY REPORTS 2019. [DOI: 10.1007/s40588-019-00124-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
32
|
Do E, Park S, Li MH, Wang JM, Ding C, Kronstad JW, Jung WH. The mitochondrial ABC transporter Atm1 plays a role in iron metabolism and virulence in the human fungal pathogen Cryptococcus neoformans. Med Mycol 2019; 56:458-468. [PMID: 29420779 DOI: 10.1093/mmy/myx073] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 08/17/2017] [Indexed: 12/19/2022] Open
Abstract
Iron-sulfur clusters (ISC) are indispensable cofactors for essential enzymes in various cellular processes. In the model yeast Saccharomyces cerevisiae, the precursor of ISCs is exported from mitochondria via a mitochondrial ABC transporter Atm1 and used for cytosolic and nuclear ISC protein assembly. Although iron homeostasis has been implicated in the virulence of the human fungal pathogen Cryptococcus neoformans, the key components of the ISC biosynthesis pathway need to be fully elucidated. In the current study, a homolog of S. cerevisiae Atm1 was identified in C. neoformans, and its function was characterized. We constructed C. neoformans mutants lacking ATM1 and found that deletion of ATM1 affected mitochondrial functions. Furthermore, we observed diminished activity of the cytosolic ISC-containing protein Leu1 and the heme-containing protein catalase in the atm1 mutant. These results suggested that Atm1 is required for the biosynthesis of ISCs in the cytoplasm as well as heme metabolism in C. neoformans. In addition, the atm1 mutants were avirulent in a murine model of cryptococcosis. Overall, our results demonstrated that Atm1 plays a critical role in iron metabolism and virulence for C. neoformans.
Collapse
Affiliation(s)
- Eunsoo Do
- Department of Systems Biotechnology, Chung-Ang University, Anseong 17546, Korea
| | - Seho Park
- Department of Systems Biotechnology, Chung-Ang University, Anseong 17546, Korea
| | - Ming-Hui Li
- College of Life and Health Sciences, Northeastern University, Shenyang, Liaoning 110015, China
| | - Jia-Mei Wang
- College of Life and Health Sciences, Northeastern University, Shenyang, Liaoning 110015, China
| | - Chen Ding
- College of Life and Health Sciences, Northeastern University, Shenyang, Liaoning 110015, China
| | - James W Kronstad
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Won Hee Jung
- Department of Systems Biotechnology, Chung-Ang University, Anseong 17546, Korea
| |
Collapse
|
33
|
Calvete CL, Martho KF, Felizardo G, Paes A, Nunes JM, Ferreira CO, Vallim MA, Pascon RC. Amino acid permeases in Cryptococcus neoformans are required for high temperature growth and virulence; and are regulated by Ras signaling. PLoS One 2019; 14:e0211393. [PMID: 30682168 PMCID: PMC6347259 DOI: 10.1371/journal.pone.0211393] [Citation(s) in RCA: 7] [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: 11/30/2018] [Accepted: 01/11/2019] [Indexed: 11/22/2022] Open
Abstract
Cryptococcosis is an Invasive Fungal Infection (IFI) caused by Cryptococcus neoformans, mainly in immunocompromised patients. Therapeutic failure due to pathogen drug resistance, treatment inconstancy and few antifungal options is a problem. The study of amino acid biosynthesis and uptake represents an opportunity to explore possible development of novel antifungals. C. neoformans has 10 amino acids permeases, two of them (Aap3 and Aap7) not expressed at the conditions tested, and five were studied previously (Aap2, Aap4, Aap5, Mup1 and Mup3). Our previous results showed that Aap4 and Aap5 are major permeases with overlapping functions. The aap4Δ/aap5Δ double mutant fails to grow in amino acids as sole nitrogen source and is avirulent in animal model. Here, we deleted the remaining amino acid permeases (AAP1, AAP6, AAP8) that showed gene expression modulation by nutritional condition and created a double mutant (aap1Δ/aap2Δ). We studied the virulence attributes of these mutants and explored the regulatory mechanism behind amino acid uptake in C. neoformans. The aap1Δ/aap2Δ strain had reduced growth at 37°C in L-amino acids, reduced capsule production and was hypovirulent in the Galleria mellonella animal model. Our data, along with previous studies, (i) complement the analysis for all 10 amino acid permeases mutants, (ii) corroborate the idea that these transporters behave as global permeases, (iii) are required during heat and nutritional stress, and (iv) are important for virulence. Our study also indicates a new possible link between Ras1 signaling and amino acids uptake.
Collapse
Affiliation(s)
- Crislaine Lambiase Calvete
- Universidade de São Paulo, Biotechnology Graduate Program, São Paulo, SP, Brazil
- Universidade Federal de São Paulo, Campus Diadema, Department of Biological Sciences, Diadema, SP, Brazil
| | - Kevin Felipe Martho
- Universidade Federal de São Paulo, Campus Diadema, Department of Biological Sciences, Diadema, SP, Brazil
| | - Gabrielle Felizardo
- Universidade Federal de São Paulo, Campus Diadema, Department of Biological Sciences, Diadema, SP, Brazil
| | - Alexandre Paes
- Universidade Federal de São Paulo, Campus Diadema, Department of Biological Sciences, Diadema, SP, Brazil
| | - João Miguel Nunes
- Universidade Federal de São Paulo, Campus Diadema, Department of Biological Sciences, Diadema, SP, Brazil
| | - Camila Oliveira Ferreira
- Universidade Federal de São Paulo, Campus Diadema, Department of Biological Sciences, Diadema, SP, Brazil
| | - Marcelo A. Vallim
- Universidade Federal de São Paulo, Campus Diadema, Department of Biological Sciences, Diadema, SP, Brazil
| | - Renata C. Pascon
- Universidade Federal de São Paulo, Campus Diadema, Department of Biological Sciences, Diadema, SP, Brazil
- * E-mail:
| |
Collapse
|
34
|
The Role of Copper Homeostasis at the Host-Pathogen Axis: From Bacteria to Fungi. Int J Mol Sci 2019; 20:ijms20010175. [PMID: 30621285 PMCID: PMC6337107 DOI: 10.3390/ijms20010175] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 12/28/2018] [Accepted: 12/29/2018] [Indexed: 02/01/2023] Open
Abstract
Copper is an essential trace element participating in many vital biological processes, however it becomes a toxic agent when in excess. Thus, precise and tight regulation of copper homeostasis processes, including transport, delivery, storage, detoxification, and efflux machineries, is important, ensuring that only the amount needed to sustain basic biological functions and simultaneously prevent copper toxicity in the cell is maintained. Numerous exciting studies have revealed that copper plays an indispensable role at the microbial pathogen-host axis for entities ranging from pathogenic bacteria to deadly fungal species. Analyses of copper homeostases in bacteria and fungi extensively demonstrate that copper is utilized by the host immune system as an anti-microbial agent. The expression of copper efflux and detoxification from microbial pathogens is induced to counteract the host's copper bombardment, which in turn disrupts these machineries, resulting in the attenuation of microbial survival in host tissue. We hereby review the latest work in copper homeostases in pathogenic bacteria and fungi and focus on the maintenance of a copper balance at the pathogen-host interaction axis.
Collapse
|
35
|
Guggisberg AM, Frasse PM, Jezewski AJ, Kafai NM, Gandhi AY, Erlinger SJ, Odom John AR. Suppression of Drug Resistance Reveals a Genetic Mechanism of Metabolic Plasticity in Malaria Parasites. mBio 2018; 9:e01193-18. [PMID: 30425143 PMCID: PMC6234871 DOI: 10.1128/mbio.01193-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 10/10/2018] [Indexed: 11/20/2022] Open
Abstract
In the malaria parasite Plasmodium falciparum, synthesis of isoprenoids from glycolytic intermediates is essential for survival. The antimalarial fosmidomycin (FSM) inhibits isoprenoid synthesis. In P. falciparum, we identified a loss-of-function mutation in HAD2 (P. falciparum 3D7_1226300 [PF3D7_1226300]) as necessary for FSM resistance. Enzymatic characterization revealed that HAD2, a member of the haloacid dehalogenase-like hydrolase (HAD) superfamily, is a phosphatase. Harnessing a growth defect in resistant parasites, we selected for suppression of HAD2-mediated FSM resistance and uncovered hypomorphic suppressor mutations in the locus encoding the glycolytic enzyme phosphofructokinase 9 (PFK9). Metabolic profiling demonstrated that FSM resistance is achieved via increased steady-state levels of methylerythritol phosphate (MEP) pathway and glycolytic intermediates and confirmed reduced PFK9 function in the suppressed strains. We identified HAD2 as a novel regulator of malaria parasite metabolism and drug sensitivity and uncovered PFK9 as a novel site of genetic metabolic plasticity in the parasite. Our report informs the biological functions of an evolutionarily conserved family of metabolic regulators and reveals a previously undescribed strategy by which malaria parasites adapt to cellular metabolic dysregulation.IMPORTANCE Unique and essential aspects of parasite metabolism are excellent targets for development of new antimalarials. An improved understanding of parasite metabolism and drug resistance mechanisms is urgently needed. The antibiotic fosmidomycin targets the synthesis of essential isoprenoid compounds from glucose and is a candidate for antimalarial development. Our report identifies a novel mechanism of drug resistance and further describes a family of metabolic regulators in the parasite. Using a novel forward genetic approach, we also uncovered mutations that suppress drug resistance in the glycolytic enzyme PFK9. Thus, we identify an unexpected genetic mechanism of adaptation to metabolic insult that influences parasite fitness and tolerance of antimalarials.
Collapse
Affiliation(s)
- Ann M Guggisberg
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Philip M Frasse
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Andrew J Jezewski
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Natasha M Kafai
- Medical Scientist Training Program, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Aakash Y Gandhi
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Samuel J Erlinger
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Audrey R Odom John
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| |
Collapse
|
36
|
Garcia-Santamarina S, Festa RA, Smith AD, Yu CH, Probst C, Ding C, Homer CM, Yin J, Noonan JP, Madhani H, Perfect JR, Thiele DJ. Genome-wide analysis of the regulation of Cu metabolism in Cryptococcus neoformans. Mol Microbiol 2018; 108:473-494. [PMID: 29608794 PMCID: PMC5980777 DOI: 10.1111/mmi.13960] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/28/2018] [Indexed: 12/13/2022]
Abstract
The ability of the human fungal pathogen Cryptococcus neoformans to adapt to variable copper (Cu) environments within the host is key for successful dissemination and colonization. During pulmonary infection, host alveolar macrophages compartmentalize Cu into the phagosome and C. neoformans Cu-detoxifying metallothioneins, MT1 and MT2, are required for survival of the pathogen. In contrast, during brain colonization the C. neoformans Cu+ importers Ctr1 and Ctr4 are required for virulence. Central for the regulation and expression of both the Cu detoxifying MT1/2 and the Cu acquisition Ctr1/4 proteins is the Cu-metalloregulatory transcription factor Cuf1, an established C. neoformans virulence factor. Due to the importance of the distinct C. neoformans Cu homeostasis mechanisms during host colonization and virulence, and to the central role of Cuf1 in regulating Cu homeostasis, we performed a combination of RNA-Seq and ChIP-Seq experiments to identify differentially transcribed genes between conditions of high and low Cu. We demonstrate that the transcriptional regulation exerted by Cuf1 is intrinsically complex and that Cuf1 also functions as a transcriptional repressor. The Cu- and Cuf1-dependent regulon in C. neoformans reveals new adaptive mechanisms for Cu homeostasis in this pathogenic fungus and identifies potential new pathogen-specific targets for therapeutic intervention in fungal infections.
Collapse
Affiliation(s)
- Sarela Garcia-Santamarina
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Richard A. Festa
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Aaron D. Smith
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Chen-Hsin Yu
- Division of Infectious Diseases, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Corinna Probst
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Chen Ding
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Christina M. Homer
- Department of Biochemistry and Biophysics, UCSF, San Francisco, California, USA
| | - Jun Yin
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - James P. Noonan
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Hiten Madhani
- Department of Biochemistry and Biophysics, UCSF, San Francisco, California, USA
| | - John R. Perfect
- Division of Infectious Diseases, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Dennis J. Thiele
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Biochemistry, Duke University School of Medicine, Durham, North Carolina, USA
| |
Collapse
|
37
|
Ries LNA, Beattie S, Cramer RA, Goldman GH. Overview of carbon and nitrogen catabolite metabolism in the virulence of human pathogenic fungi. Mol Microbiol 2017; 107:277-297. [PMID: 29197127 DOI: 10.1111/mmi.13887] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/20/2017] [Accepted: 11/23/2017] [Indexed: 12/12/2022]
Abstract
It is estimated that fungal infections, caused most commonly by Candida albicans, Aspergillus fumigatus and Cryptococcus neoformans, result in more deaths annually than malaria or tuberculosis. It has long been hypothesized the fungal metabolism plays a critical role in virulence though specific nutrient sources utilized by human pathogenic fungi in vivo has remained enigmatic. However, the metabolic utilisation of preferred carbon and nitrogen sources, encountered in a host niche-dependent manner, is known as carbon catabolite and nitrogen catabolite repression (CCR, NCR), and has been shown to be important for virulence. Several sensory and uptake systems exist, including carbon and nitrogen source-specific sensors and transporters, that allow scavenging of preferred nutrient sources. Subsequent metabolic utilisation is governed by transcription factors, whose functions and essentiality differ between fungal species. Furthermore, additional factors exist that contribute to the implementation of CCR and NCR. The role of the CCR and NCR-related factors in virulence varies greatly between fungal species and a substantial gap in knowledge exists regarding specific pathways. Further elucidation of carbon and nitrogen metabolism mechanisms is therefore required in a fungal species- and animal model-specific manner in order to screen for targets that are potential candidates for anti-fungal drug development.
Collapse
Affiliation(s)
- Laure Nicolas Annick Ries
- Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes, Ribeirão Preto, São Paulo, 3900, CEP 14049-900, Brazil
| | - Sarah Beattie
- Department of Microbiology & Immunology, Geisel School of Medicine at Dartmouth, 74 College Street Remsen 213, Hanover, NH 03755, USA
| | - Robert A Cramer
- Department of Microbiology & Immunology, Geisel School of Medicine at Dartmouth, 74 College Street Remsen 213, Hanover, NH 03755, USA
| | - Gustavo H Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Avenida do Café s/n°, Ribeirão Preto, São Paulo, CEP 14040903, Brazil
| |
Collapse
|
38
|
de S Araújo GR, Souza WD, Frases S. The hidden pathogenic potential of environmental fungi. Future Microbiol 2017; 12:1533-1540. [PMID: 29168657 DOI: 10.2217/fmb-2017-0124] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Invasive fungal infections are a growing threat to immunocompromised patients, highlighting the importance of monitoring fungal pathogens. Global warming (including climatic oscillations) may select for environmental species that have acquired thermotolerance, a key step toward pathogenesis to humans. Also, important virulence factors have developed in environmental fungi, because they are essential for yeast survival in the environment. Thus, fungi traditionally regarded as nonpathogenic to humans have virulence factors similar to those of their pathogenic relatives. Here, we highlight the emergence of saprophytic environmental fungi - including species of Cryptococcus, Aspergillus, Penicillium, Candida and Scedosporium - as new human pathogens. Emerging pathogens are, in some cases, resistant to the available antifungals, potentiating the threat of novel fungal diseases.
Collapse
Affiliation(s)
- Glauber R de S Araújo
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Wanderley de Souza
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Susana Frases
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| |
Collapse
|
39
|
Helsel ME, White EJ, Razvi SZA, Alies B, Franz KJ. Chemical and functional properties of metal chelators that mobilize copper to elicit fungal killing of Cryptococcus neoformans. Metallomics 2017; 9:69-81. [PMID: 27853789 DOI: 10.1039/c6mt00172f] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A panel of iron (Fe) and copper (Cu) chelators was screened for growth inhibitory activity against the fungal pathogen Cryptococcus neoformans. Select bidentate metal-binding ligands containing mixed O,S or O,N donor atoms were identified as agents that induce cell killing in a Cu-dependent manner. Conversely, structurally similar ligands with O,O donor atoms did not inhibit C. neoformans growth regardless of Cu status. Studies of Cu(ii) and Cu(i) binding affinity, lipophilicity, and growth recovery assays of Cu-import deficient cells identified lipophilicity of thermodynamically stable CuIIL2 complexes as the best predictor of antifungal activity. These same complexes induce cellular hyperaccumulation of Zn and Fe in addition to Cu. The results described here present the utility of appropriate metal-binding ligands as potential antifungal agents that manipulate cellular metal balance as an antimicrobial strategy.
Collapse
Affiliation(s)
- Marian E Helsel
- Department of Chemistry, Duke University, French Family Science Center, 124 Science Drive, 22708, Durham, NC, USA.
| | - Elizabeth J White
- Department of Chemistry, Duke University, French Family Science Center, 124 Science Drive, 22708, Durham, NC, USA.
| | - Sayyeda Zeenat A Razvi
- Department of Chemistry, Duke University, French Family Science Center, 124 Science Drive, 22708, Durham, NC, USA.
| | - Bruno Alies
- Department of Chemistry, Duke University, French Family Science Center, 124 Science Drive, 22708, Durham, NC, USA.
| | - Katherine J Franz
- Department of Chemistry, Duke University, French Family Science Center, 124 Science Drive, 22708, Durham, NC, USA.
| |
Collapse
|
40
|
Boral H, Metin B, Döğen A, Seyedmousavi S, Ilkit M. Overview of selected virulence attributes in Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans, Trichophyton rubrum, and Exophiala dermatitidis. Fungal Genet Biol 2017; 111:92-107. [PMID: 29102684 DOI: 10.1016/j.fgb.2017.10.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 10/24/2017] [Accepted: 10/27/2017] [Indexed: 12/13/2022]
Abstract
The incidence of fungal diseases has been increasing since 1980, and is associated with excessive morbidity and mortality, particularly among immunosuppressed patients. Of the known 625 pathogenic fungal species, infections caused by the genera Aspergillus, Candida, Cryptococcus, and Trichophyton are responsible for more than 300 million estimated episodes of acute or chronic infections worldwide. In addition, a rather neglected group of opportunistic fungi known as black yeasts and their filamentous relatives cause a wide variety of recalcitrant infections in both immunocompetent and immunosuppressed hosts. This article provides an overview of selected virulence factors that are known to suppress host immunity and enhance the infectivity of these fungi.
Collapse
Affiliation(s)
- Hazal Boral
- Division of Mycology, Department of Microbiology, Faculty of Medicine, University of Çukurova, Adana, Turkey
| | - Banu Metin
- Department of Food Engineering, Faculty of Engineering and Natural Sciences, Istanbul Sabahattin Zaim University, Istanbul, Turkey
| | - Aylin Döğen
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, University of Mersin, Mersin, Turkey
| | - Seyedmojtaba Seyedmousavi
- Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands; Invasive Fungi Research Center, Mazandaran University of Medical Sciences, Sari, Iran; Center of Excellence for Infection Biology and Antimicrobial Pharmacology, Tehran, Iran
| | - Macit Ilkit
- Division of Mycology, Department of Microbiology, Faculty of Medicine, University of Çukurova, Adana, Turkey.
| |
Collapse
|
41
|
Garcia-Santamarina S, Uzarska MA, Festa RA, Lill R, Thiele DJ. Cryptococcus neoformans Iron-Sulfur Protein Biogenesis Machinery Is a Novel Layer of Protection against Cu Stress. mBio 2017; 8:e01742-17. [PMID: 29089435 PMCID: PMC5666163 DOI: 10.1128/mbio.01742-17] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 10/03/2017] [Indexed: 11/20/2022] Open
Abstract
Copper (Cu) ions serve as catalytic cofactors to drive key biochemical processes, and yet Cu levels that exceed cellular homeostatic control capacity are toxic. The underlying mechanisms for Cu toxicity are poorly understood. During pulmonary infection by the fungal pathogen Cryptococcus neoformans, host alveolar macrophages compartmentalize Cu to the phagosome, and the ability to detoxify Cu is critical for its survival and virulence. Here, we report that iron-sulfur (Fe-S) clusters are critical targets of Cu toxicity in both Saccharomyces cerevisiae and C. neoformans in a manner that depends on the accessibility of Cu to the Fe-S cofactor. To respond to this Cu-dependent Fe-S stress, C. neoformans induces the transcription of mitochondrial ABC transporter Atm1, which functions in cytosolic-nuclear Fe-S protein biogenesis in response to Cu and in a manner dependent on the Cu metalloregulatory transcription factor Cuf1. As Atm1 functions in exporting an Fe-S precursor from the mitochondrial matrix to the cytosol, C. neoformans cells depleted for Atm1 are sensitive to Cu even while the Cu-detoxifying metallothionein proteins are highly expressed. We provide evidence for a previously unrecognized microbial defense mechanism to deal with Cu toxicity, and we highlight the importance for C. neoformans of having several distinct mechanisms for coping with Cu toxicity which together could contribute to the success of this microbe as an opportunistic human fungal pathogen.IMPORTANCEC. neoformans is an opportunistic pathogen that causes lethal meningitis in over 650,000 people annually. The severity of C. neoformans infections is further compounded by the use of toxic or poorly effective systemic antifungal agents as well as by the difficulty of diagnosis. Cu is a natural potent antimicrobial agent that is compartmentalized within the macrophage phagosome and used by innate immune cells to neutralize microbial pathogens. While the Cu detoxification machinery of C. neoformans is essential for virulence, little is known about the mechanisms by which Cu kills fungi. Here we report that Fe-S cluster-containing proteins, including members of the Fe-S protein biogenesis machinery itself, are critical targets of Cu toxicity and therefore that this biosynthetic process provides an important layer of defense against high Cu levels. Given the role of Cu ionophores as antimicrobials, understanding how Cu is toxic to microorganisms could lead to the development of effective, broad-spectrum antimicrobials. Moreover, understanding Cu toxicity could provide additional insights into the pathophysiology of human diseases of Cu overload such as Wilson's disease.
Collapse
Affiliation(s)
| | - Marta A Uzarska
- Institut für Zytobiologie & Zytopathologie, Philipps-Universität, Marburg, Germany
| | - Richard A Festa
- Duke University School of Medicine, Durham, North Carolina, USA
| | - Roland Lill
- Institut für Zytobiologie & Zytopathologie, Philipps-Universität, Marburg, Germany
- LOEWE Zentrum für Synthetische Mikrobiologie SynMikro, Marburg, Germany
| | - Dennis J Thiele
- Duke University School of Medicine, Durham, North Carolina, USA
- Department of Pharmacology and Cancer Biology, Department of Biochemistry, Duke University School of Medicine, Durham, North Carolina, USA
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA
| |
Collapse
|
42
|
Duarte-Oliveira C, Rodrigues F, Gonçalves SM, Goldman GH, Carvalho A, Cunha C. The Cell Biology of the Trichosporon-Host Interaction. Front Cell Infect Microbiol 2017; 7:118. [PMID: 28439501 PMCID: PMC5383668 DOI: 10.3389/fcimb.2017.00118] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 03/23/2017] [Indexed: 11/13/2022] Open
Abstract
Fungi of the genus Trichosporon are increasingly recognized as causative agents of superficial and invasive fungal disease in humans. Although most species are considered commensals of the human skin and gastrointestinal tract, these basidiomycetes are an increasing cause of fungal disease among immunocompromised hosts, such as hematological patients and solid organ transplant recipients. The initiation of commensal or pathogenic programs by Trichosporon spp. involves the adaptation to the host microenvironment and its immune system. However, the exact virulence factors activated upon the transition to a pathogenic lifestyle, including the intricate biology of the cell wall, and how these interact with and subvert the host immune responses remain largely unknown. Here, we revisit our current understanding of the virulence attributes of Trichosporon spp., particularly T. asahii, and their interaction with the host immune system, and accommodate this knowledge within novel perspectives on fungal diagnostics and therapeutics.
Collapse
Affiliation(s)
- Cláudio Duarte-Oliveira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of MinhoBraga, Portugal.,ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
| | - Fernando Rodrigues
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of MinhoBraga, Portugal.,ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
| | - Samuel M Gonçalves
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of MinhoBraga, Portugal.,ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
| | - Gustavo H Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São PauloSão Paulo, Brazil
| | - Agostinho Carvalho
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of MinhoBraga, Portugal.,ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
| | - Cristina Cunha
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of MinhoBraga, Portugal.,ICVS/3B's - PT Government Associate LaboratoryBraga/Guimarães, Portugal
| |
Collapse
|
43
|
Bouklas T, Jain N, Fries BC. Modulation of Replicative Lifespan in Cryptococcus neoformans: Implications for Virulence. Front Microbiol 2017; 8:98. [PMID: 28194146 PMCID: PMC5276861 DOI: 10.3389/fmicb.2017.00098] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 01/13/2017] [Indexed: 12/12/2022] Open
Abstract
The fungal pathogen, Cryptococcus neoformans, has been shown to undergo replicative aging. Old cells are characterized by advanced generational age and phenotypic changes that appear to mediate enhanced resistance to host and antifungal-based killing. As a consequence of this age-associated resilience, old cells accumulate during chronic infection. Based on these findings, we hypothesized that shifting the generational age of a pathogenic yeast population would alter its vulnerability to the host and affect its virulence. SIR2 is a well-conserved histone deacetylase, and a pivotal target for the development of anti-aging drugs. We tested its effect on C. neoformans’ replicative lifespan (RLS). First, a mutant C. neoformans strain (sir2Δ) was generated, and confirmed a predicted shortened RLS in sir2Δ cells consistent with its known role in aging. Next, RLS analysis showed that treatment of C. neoformans with Sir2p-agonists resulted in a significantly prolonged RLS, whereas treatment with a Sir2p-antagonist shortened RLS. RLS modulating effects were dependent on SIR2 and not observed in sir2Δ cells. Because SIR2 loss resulted in a slightly impaired fitness, effects of genetic RLS modulation on virulence could not be compared with wild type cells. Instead we chose to chemically modulate RLS, and investigated the effect of Sir2p modulating drugs on C. neoformans cells in a Galleria mellonella infection model. Consistent with our hypothesis that shifts in the generational age of the infecting yeast population alters its vulnerability to host cells, we observed decreased virulence of C. neoformans in the Galleria host when RLS was prolonged by treatment with Sir2p agonists. In contrast, treatment with a Sir2p antagonist, which shortens RLS enhanced virulence in Galleria. In addition, combination of Sir2p agonists with antifungal therapy enhanced the antifungal’s effect. Importantly, no difference in virulence was observed with drug treatment when sir2Δ cells were used for infection, which confirmed target specificity and ruled out non-specific effects of the drugs on the Galleria host. Thus, this study suggests that RLS modulating drugs, such as Sir2p agonists, shift lifespan and vulnerability of the fungal population, and should be further investigated as a potential class of novel antifungal drug targets that can enhance antifungal efficacy.
Collapse
Affiliation(s)
- Tejas Bouklas
- Department of Medicine (Division of Infectious Diseases), Stony Brook University, Stony BrookNY, USA; Department of Biomedical Sciences, Long Island University-Post, BrookvilleNY, USA
| | - Neena Jain
- Department of Medicine (Division of Infectious Diseases), Albert Einstein College of Medicine of Yeshiva University, Bronx NY, USA
| | - Bettina C Fries
- Department of Medicine (Division of Infectious Diseases), Stony Brook University, Stony BrookNY, USA; Department of Medicine (Division of Infectious Diseases), Albert Einstein College of Medicine of Yeshiva University, BronxNY, USA; Department of Molecular Genetics and Microbiology, Stony Brook University, Stony BrookNY, USA; Department of Microbiology and Immunology, Albert Einstein College of Medicine of Yeshiva University, BronxNY, USA
| |
Collapse
|
44
|
Hu G, Caza M, Bakkeren E, Kretschmer M, Bairwa G, Reiner E, Kronstad J. A P4-ATPase subunit of the Cdc50 family plays a role in iron acquisition and virulence in Cryptococcus neoformans. Cell Microbiol 2017; 19. [PMID: 28061020 DOI: 10.1111/cmi.12718] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 12/01/2016] [Accepted: 01/03/2017] [Indexed: 12/29/2022]
Abstract
The pathogenic fungus Cryptococcus neoformans delivers virulence factors such as capsule polysaccharide to the cell surface to cause disease in vertebrate hosts. In this study, we screened for mutants sensitive to the secretion inhibitor brefeldin A to identify secretory pathway components that contribute to virulence. We identified an ortholog of the cell division control protein 50 (Cdc50) family of the noncatalytic subunit of type IV P-type ATPases (flippases) that establish phospholipid asymmetry in membranes and function in vesicle-mediated trafficking. We found that a cdc50 mutant in C. neoformans was defective for survival in macrophages, attenuated for virulence in mice and impaired in iron acquisition. The mutant also showed increased sensitivity to drugs associated with phospholipid metabolism (cinnamycin and miltefosine), the antifungal drug fluconazole and curcumin, an iron chelator that accumulates in the endoplasmic reticulum. Cdc50 is expected to function with catalytic subunits of flippases, and we previously documented the involvement of the flippase aminophospholipid translocases (Apt1) in virulence factor delivery. A comparison of phenotypes with mutants defective in genes encoding candidate flippases (designated APT1, APT2, APT3, and APT4) revealed similarities primarily between cdc50 and apt1 suggesting a potential functional interaction. Overall, these results highlight the importance of membrane composition and homeostasis for the ability of C. neoformans to cause disease.
Collapse
Affiliation(s)
- Guanggan Hu
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Mélissa Caza
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Erik Bakkeren
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada.,Institute of Microbiology, Zurich, Switzerland
| | - Matthias Kretschmer
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Gaurav Bairwa
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Ethan Reiner
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - James Kronstad
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| |
Collapse
|
45
|
Gerstein AC, Nielsen K. It's not all about us: evolution and maintenance of Cryptococcus virulence requires selection outside the human host. Yeast 2017; 34:143-154. [PMID: 27862271 DOI: 10.1002/yea.3222] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 11/02/2016] [Accepted: 11/04/2016] [Indexed: 12/11/2022] Open
Abstract
Cryptococcus is predominantly an AIDS-related pathogen that causes significant morbidity and mortality in immunocompromised patients. Research studies have historically focused on understanding how the organism causes human disease through the use of in vivo and in vitro model systems to identify virulence factors. Cryptococcus is not an obligate pathogen, however, as human-human transmission is either absent or rare. Selection in the environment must thus be invoked to shape the evolution of this taxa, and directly influences genotypic and trait diversity. Importantly, the evolution and maintenance of pathogenicity must also stem directly from environmental selection. To that end, here we examine abiotic and biotic stresses in the environment, and discuss how they could shape the factors that are commonly identified as important virulence traits. We identify a number of important unanswered questions about Cryptococcus diversity and evolution that are critical for understanding this deadly pathogen, and discuss how implementation of modern sampling and genomic tools could be utilized to answer these questions. Copyright © 2016 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Aleeza C Gerstein
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Kirsten Nielsen
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA
| |
Collapse
|
46
|
Azevedo RVDM, Rizzo J, Rodrigues ML. Virulence Factors as Targets for Anticryptococcal Therapy. J Fungi (Basel) 2016; 2:jof2040029. [PMID: 29376946 PMCID: PMC5715936 DOI: 10.3390/jof2040029] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/18/2016] [Accepted: 11/25/2016] [Indexed: 12/24/2022] Open
Abstract
The global mortality due to cryptococcosis caused by Cryptococcus neoformans or C. gattii is unacceptably high. Currently available therapies are decades old and may be impacted by drug resistance. Therefore, the need for more effective antifungal drugs for cryptococcosis is evident. A number of Cryptococcus virulence factors have been studied in detail, providing crucial information about the fungal biology and putative molecular targets for antifungals. This review focuses on the use of well-described virulence factors of Cryptococcus as potential anticryptococcal agents.
Collapse
Affiliation(s)
- Renata V D M Azevedo
- Fundação Oswaldo Cruz-Fiocruz, Centro de Desenvolvimento Tecnológico em Saúde (CDTS), 21040-361 Rio de Janeiro, Brazil.
| | - Juliana Rizzo
- Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil.
- Instituto de Bioquímica Médica (IBqM), Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil.
| | - Marcio L Rodrigues
- Fundação Oswaldo Cruz-Fiocruz, Centro de Desenvolvimento Tecnológico em Saúde (CDTS), 21040-361 Rio de Janeiro, Brazil.
- Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, 21941-902 Rio de Janeiro, Brazil.
| |
Collapse
|
47
|
Dhamgaye S, Qu Y, Peleg AY. Polymicrobial infections involving clinically relevant Gram-negative bacteria and fungi. Cell Microbiol 2016; 18:1716-1722. [PMID: 27665610 DOI: 10.1111/cmi.12674] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 09/20/2016] [Accepted: 09/22/2016] [Indexed: 01/02/2023]
Abstract
Interactions between fungi and bacteria and their relevance to human health and disease have recently attracted increased attention in biomedical fields. Emerging evidence shows that bacteria and fungi can have synergistic or antagonistic interactions, each with important implications for human colonization and disease. It is now appreciated that some of these interactions may be strategic and helps promote the survival of one or both microorganisms within the host. This review will shed light on clinically relevant interactions between fungi and Gram-negative bacteria. Mechanism of interaction, host immune responses, and preventive measures will also be reviewed.
Collapse
Affiliation(s)
- Sanjiveeni Dhamgaye
- Biomedicine Discovery Institute, Department of Microbiology, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Victoria, Australia
| | - Yue Qu
- Biomedicine Discovery Institute, Department of Microbiology, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Victoria, Australia.,Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Anton Y Peleg
- Biomedicine Discovery Institute, Department of Microbiology, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Victoria, Australia.,Department of Infectious Diseases, The Alfred Hospital and Central Clinical School, Monash University, Melbourne, Victoria, Australia
| |
Collapse
|
48
|
Martho KFC, de Melo AT, Takahashi JPF, Guerra JM, Santos DCDS, Purisco SU, Melhem MDSC, Fazioli RDA, Phanord C, Sartorelli P, Vallim MA, Pascon RC. Amino Acid Permeases and Virulence in Cryptococcus neoformans. PLoS One 2016; 11:e0163919. [PMID: 27695080 PMCID: PMC5047642 DOI: 10.1371/journal.pone.0163919] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 09/17/2016] [Indexed: 11/19/2022] Open
Abstract
Fungal opportunistic pathogens colonize various environments, from plants and wood to human and animal tissue. Regarding human pathogens, one great challenge during contrasting niche occupation is the adaptation to different conditions, such as temperature, osmolarity, salinity, pressure, oxidative stress and nutritional availability, which may constitute sources of stress that need to be tolerated and overcome. As an opportunistic pathogen, C. neoformans faces exactly these situations during the transition from the environment to the human host, encountering nutritional constraints. Our previous and current research on amino acid biosynthetic pathways indicates that amino acid permeases are regulated by the presence of the amino acids, nitrogen and temperature. Saccharomyces cerevisiae and Candida albicans have twenty-four and twenty-seven genes encoding amino acid permeases, respectively; conversely, they are scarce in number in Basidiomycetes (C. neoformans, Coprinopsis cinerea and Ustilago maydis), where nine to ten permease genes can be found depending on the species. In this study, we have demonstrated that two amino acid permeases are essential for virulence in C. neoformans. Our data showed that C. neoformans uses two global and redundant amino acid permeases, Aap4 and Aap5 to respond correctly to thermal and oxidative stress. Double deletion of these permeases causes growth arrest in C. neoformans at 37°C and in the presence of hydrogen peroxide. The inability to uptake amino acid at a higher temperature and under oxidative stress also led to virulence attenuation in vivo. Our data showed that thermosensitivity caused by the lack of permeases Aap4 and Aap5 can be remedied by alkaline conditions (higher pH) and salinity. Permeases Aap4 and Aap5 are also required during fluconazole stress and they are the target of the plant secondary metabolite eugenol, a potent antifungal inhibitor that targets amino acid permeases. In summary, our work unravels (i) interesting physiological property of C. neoformans regarding its amino acid uptake system; (ii) an important aspect of virulence, which is the need for amino acid permeases during thermal and oxidative stress resistance and, hence, host invasion and colonization; and (iii) provides a convenient prototype for antifungal development, which are the amino acid permeases Aap4/Aap5 and their inhibitor.
Collapse
Affiliation(s)
- Kevin Felipe Cruz Martho
- Instituto de Ciências Ambientais, Química e Farmacêuticas, Universidade Federal de São Paulo, Rua Arthur Ridel, 275, Diadema, SP, Brazil
| | - Amanda Teixeira de Melo
- Instituto de Ciências Ambientais, Química e Farmacêuticas, Universidade Federal de São Paulo, Rua Arthur Ridel, 275, Diadema, SP, Brazil
| | | | | | | | - Sônia Ueda Purisco
- Mycology Unit, Adolfo Lutz Institute, Secretary of Health, São Paulo, Brazil
| | | | | | - Clerlune Phanord
- Instituto de Ciências Ambientais, Química e Farmacêuticas, Universidade Federal de São Paulo, Rua Arthur Ridel, 275, Diadema, SP, Brazil
| | - Patrícia Sartorelli
- Instituto de Ciências Ambientais, Química e Farmacêuticas, Universidade Federal de São Paulo, Rua Arthur Ridel, 275, Diadema, SP, Brazil
| | - Marcelo A. Vallim
- Instituto de Ciências Ambientais, Química e Farmacêuticas, Universidade Federal de São Paulo, Rua Arthur Ridel, 275, Diadema, SP, Brazil
| | - Renata C. Pascon
- Instituto de Ciências Ambientais, Química e Farmacêuticas, Universidade Federal de São Paulo, Rua Arthur Ridel, 275, Diadema, SP, Brazil
- * E-mail:
| |
Collapse
|
49
|
Banerjee D, Bloom ALM, Panepinto JC. Opposing PKA and Hog1 signals control the post-transcriptional response to glucose availability in Cryptococcus neoformans. Mol Microbiol 2016; 102:306-320. [PMID: 27387858 DOI: 10.1111/mmi.13461] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/06/2016] [Indexed: 12/17/2022]
Abstract
The pathogenic fungus Cryptococcus neoformans must adapt to glucose-limited conditions in the lung and glucose replete conditions upon dissemination to the brain. We report that glucose controls ribosome biogenesis and translation by modulating mRNA decay through a balance of PKA and Hog1 signalling. Glucose signalling through PKA stabilized ribosomal protein (RP) mRNAs whereas glucose starvation destabilized RP transcripts through Hog1. Glucose starvation-induced oxidative stress response genes, and treatment of glucose-fed cells with reactive oxygen species (ROS) generating compounds repressed RP transcripts, both of which were dependent on Hog1. Stabilization of RP transcripts led to retention of polysomes in a hog1Δ mutant, whereas stabilization of RP transcripts by cyclic AMP did not affect translation repression, suggesting that Hog1 alone signals translation repression. In sum, this work describes a novel antagonism between PKA and Hog1 controlling ribosome biogenesis via mRNA stability in response to glucose availability in this important human pathogen.
Collapse
Affiliation(s)
- Dithi Banerjee
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, State University of New York at Buffalo, Buffalo, NY, 14214, USA
| | - Amanda L M Bloom
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, State University of New York at Buffalo, Buffalo, NY, 14214, USA
| | - John C Panepinto
- Department of Microbiology and Immunology, Witebsky Center for Microbial Pathogenesis and Immunology, State University of New York at Buffalo, Buffalo, NY, 14214, USA.
| |
Collapse
|
50
|
Blume M, Nitzsche R, Sternberg U, Gerlic M, Masters SL, Gupta N, McConville MJ. A Toxoplasma gondii Gluconeogenic Enzyme Contributes to Robust Central Carbon Metabolism and Is Essential for Replication and Virulence. Cell Host Microbe 2016; 18:210-20. [PMID: 26269956 DOI: 10.1016/j.chom.2015.07.008] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Revised: 05/25/2015] [Accepted: 07/14/2015] [Indexed: 10/23/2022]
Abstract
The expression of gluconeogenic enzymes is typically repressed when glucose is available. The protozoan parasite Toxoplasma gondii utilizes host glucose to sustain high rates of intracellular replication. However, despite their preferential utilization of glucose, intracellular parasites constitutively express two isoforms of the gluconeogenic enzyme fructose 1,6-bisphosphatase (TgFBP1 and TgFBP2). The rationale for constitutive expression of FBPases in T. gondii remains unclear. We find that conditional knockdown of TgFBP2 results in complete loss of intracellular growth in vitro under glucose-replete conditions and loss of acute virulence in mice. TgFBP2 deficiency was rescued by expression of catalytically active FBPase and was associated with altered glycolytic and mitochondrial TCA cycle fluxes, as well as dysregulation of glycolipid, amylopectin, and fatty acid biosynthesis. Futile cycling between gluconeogenic and glycolytic enzymes may constitute a regulatory mechanism that allows T. gondii to rapidly adapt to changes in nutrient availability in different host cells.
Collapse
Affiliation(s)
- Martin Blume
- Department of Biochemistry and Molecular Biology, Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Richard Nitzsche
- Department of Molecular Parasitology, Humboldt University, Berlin 10115, Germany
| | - Ulrich Sternberg
- Department of Molecular Parasitology, Humboldt University, Berlin 10115, Germany
| | - Motti Gerlic
- Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, and Department of Medical Biology, The University of Melbourne, Parkville, VIC 3010, Australia; Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Seth L Masters
- Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, and Department of Medical Biology, The University of Melbourne, Parkville, VIC 3010, Australia
| | - Nishith Gupta
- Department of Molecular Parasitology, Humboldt University, Berlin 10115, Germany
| | - Malcolm J McConville
- Department of Biochemistry and Molecular Biology, Bio21 Institute of Molecular Science and Biotechnology, The University of Melbourne, Parkville, VIC 3010, Australia.
| |
Collapse
|