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Katsipoulaki M, Stappers MHT, Malavia-Jones D, Brunke S, Hube B, Gow NAR. Candida albicans and Candida glabrata: global priority pathogens. Microbiol Mol Biol Rev 2024; 88:e0002123. [PMID: 38832801 DOI: 10.1128/mmbr.00021-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024] Open
Abstract
SUMMARYA significant increase in the incidence of Candida-mediated infections has been observed in the last decade, mainly due to rising numbers of susceptible individuals. Recently, the World Health Organization published its first fungal pathogen priority list, with Candida species listed in medium, high, and critical priority categories. This review is a synthesis of information and recent advances in our understanding of two of these species-Candida albicans and Candida glabrata. Of these, C. albicans is the most common cause of candidemia around the world and is categorized as a critical priority pathogen. C. glabrata is considered a high-priority pathogen and has become an increasingly important cause of candidemia in recent years. It is now the second most common causative agent of candidemia in many geographical regions. Despite their differences and phylogenetic divergence, they are successful as pathogens and commensals of humans. Both species can cause a broad variety of infections, ranging from superficial to potentially lethal systemic infections. While they share similarities in certain infection strategies, including tissue adhesion and invasion, they differ significantly in key aspects of their biology, interaction with immune cells, host damage strategies, and metabolic adaptations. Here we provide insights on key aspects of their biology, epidemiology, commensal and pathogenic lifestyles, interactions with the immune system, and antifungal resistance.
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Affiliation(s)
- Myrto Katsipoulaki
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Mark H T Stappers
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Dhara Malavia-Jones
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Sascha Brunke
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Hans Knoell Institute, Jena, Germany
- Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Neil A R Gow
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
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Heaven T, Armitage AD, Xu X, Goddard MR, Cockerton HM. Dose-Dependent Genetic Resistance to Azole Fungicides Found in the Apple Scab Pathogen. J Fungi (Basel) 2023; 9:1136. [PMID: 38132737 PMCID: PMC10744243 DOI: 10.3390/jof9121136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 11/13/2023] [Accepted: 11/17/2023] [Indexed: 12/23/2023] Open
Abstract
The evolution of azole resistance in fungal pathogens presents a major challenge in both crop production and human health. Apple orchards across the world are faced with the emergence of azole fungicide resistance in the apple scab pathogen Venturia inaequalis. Target site point mutations observed in this fungus to date cannot fully explain the reduction in sensitivity to azole fungicides. Here, polygenic resistance to tebuconazole was studied across a population of V. inaequalis. Genotyping by sequencing allowed Quantitative Trait Loci (QTLs) mapping to identify the genetic components controlling this fungicide resistance. Dose-dependent genetic resistance was identified, with distinct genetic components contributing to fungicide resistance at different exposure levels. A QTL within linkage group seven explained 65% of the variation in the effective dose required to reduce growth by 50% (ED50). This locus was also involved in resistance at lower fungicide doses (ED10). A second QTL in linkage group one was associated with dose-dependent resistance, explaining 34% of variation at low fungicide doses (ED10), but did not contribute to resistance at higher doses (ED50 and ED90). Within QTL regions, non-synonymous mutations were observed in several ATP-Binding Cassette and Major Facilitator SuperFamily transporter genes. These findings provide insight into the mechanisms of fungicide resistance that have evolved in horticultural pathogens. Identification of resistance gene candidates supports the development of molecular diagnostics to inform management practices.
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Affiliation(s)
- Thomas Heaven
- National Institute of Agricultural Botany, New Road, East Malling, West Malling, Kent ME19 6BJ, UK;
- The School of Life and Environmental Sciences, University of Lincoln, Lincoln LN6 7DL, UK;
- John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | | | - Xiangming Xu
- National Institute of Agricultural Botany, New Road, East Malling, West Malling, Kent ME19 6BJ, UK;
| | - Matthew R. Goddard
- The School of Life and Environmental Sciences, University of Lincoln, Lincoln LN6 7DL, UK;
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3
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Fernandes MZ, Caetano CF, Gaspar C, Oliveira AS, Palmeira-de-Oliveira R, Martinez-de-Oliveira J, Rolo J, Palmeira-de-Oliveira A. Uncovering the Yeast Diversity in the Female Genital Tract: An Exploration of Spatial Distribution and Antifungal Resistance. Pathogens 2023; 12:pathogens12040595. [PMID: 37111481 PMCID: PMC10145200 DOI: 10.3390/pathogens12040595] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 04/10/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
Candida albicans is the leading cause of vulvovaginal yeast infections; however, other species are becoming relevant in this niche. The spatial distribution of these fungi in the female genital tract remains poorly understood. In this study, swab samples were collected from 33 patients, first from the anterior vulva and then from the upper third and right lateral wall of the vagina: 16 were with symptoms of vulvovaginal candidiasis and 17 were without characteristic symptoms; furthermore, the genus and species of each isolate were identified. In vitro susceptibility testing for fluconazole and clotrimazole was performed for all isolates. Candida albicans was the most common species (63.6%), followed by Rhodotorula spp. (51.5%), and then Candida parapsilosis (15.2%). Rhodotorula spp. and C. parapsilosis were more commonly associated with colonization, and C. albicans with infection. Rhodotorula spp. isolates presented a low susceptibility to fluconazole, with the MIC ranging from 32 to >64 µg/mL. Differences in susceptibility to fluconazole and clotrimazole between the pairs of vaginal and vulvar isolates were found for Candida albicans, Rhodotorula spp., and Nakaseomyces glabratus. The results suggest that different niches may impact the susceptibility profiles of the isolates, as well as their different clinical behaviors.
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Affiliation(s)
- Mariana Zagalo Fernandes
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilhã, Portugal
- Faculty of Health Sciences, University of Beira Interior, 6200-506 Covilhã, Portugal
| | - Cátia Filipa Caetano
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilhã, Portugal
- Faculty of Health Sciences, University of Beira Interior, 6200-506 Covilhã, Portugal
| | - Carlos Gaspar
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilhã, Portugal
- Faculty of Health Sciences, University of Beira Interior, 6200-506 Covilhã, Portugal
- Labfit, Health Products Research and Development Lda, 6200-284 Covilhã, Portugal
| | - Ana Sofia Oliveira
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilhã, Portugal
- Faculty of Health Sciences, University of Beira Interior, 6200-506 Covilhã, Portugal
| | - Rita Palmeira-de-Oliveira
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilhã, Portugal
- Faculty of Health Sciences, University of Beira Interior, 6200-506 Covilhã, Portugal
- Labfit, Health Products Research and Development Lda, 6200-284 Covilhã, Portugal
| | | | - Joana Rolo
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilhã, Portugal
- Faculty of Health Sciences, University of Beira Interior, 6200-506 Covilhã, Portugal
| | - Ana Palmeira-de-Oliveira
- CICS-UBI-Health Sciences Research Centre, University of Beira Interior, 6200-506 Covilhã, Portugal
- Faculty of Health Sciences, University of Beira Interior, 6200-506 Covilhã, Portugal
- Labfit, Health Products Research and Development Lda, 6200-284 Covilhã, Portugal
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Patel SK, Sahu SR, Utkalaja BG, Bose S, Acharya N. Pol32, an accessory subunit of DNA polymerase delta, plays an essential role in genome stability and pathogenesis of Candida albicans. Gut Microbes 2023; 15:2163840. [PMID: 36601868 PMCID: PMC9828637 DOI: 10.1080/19490976.2022.2163840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Candida albicans is a pathobiont that inflicts serious bloodstream fungal infections in individuals with compromised immunity and gut dysbiosis. Genomic diversity in the form of copy number alteration, ploidy variation, and loss of heterozygosity as an adaptive mechanism to adverse environments is frequently observed in C. albicans. Such genomic variations also confer a varied degree of fungal virulence and drug resistance, yet the factors propelling these are not completely understood. DNA polymerase delta (Polδ) is an essential replicative DNA polymerase in the eukaryotic cell and is yet to be characterized in C. albicans. Therefore, this study was designed to gain insights into the role of Polδ, especially its non-essential subunit Pol32, in the genome plasticity and life cycle of C. albicans. PCNA, the DNA clamp, recruits Polδ to the replication fork for processive DNA replication. Unlike in Saccharomyces cerevisiae, the PCNA interaction protein (PIP) motif of CaPol32 is critical for Polδ's activity during DNA replication. Our comparative genetic analyses and whole-genome sequencing of POL32 proficient and deficient C. albicans cells revealed a critical role of Pol32 in DNA replication, cell cycle progression, and genome stability as SNPs, indels, and repeat variations were largely accumulated in pol32 null strain. The loss of pol32 in C. albicans conferred cell wall deformity; Hsp90 mediated azoles resistance, biofilm development, and a complete attenuation of virulence in an animal model of systemic candidiasis. Thus, although Pol32 is dispensable for cell survival, its function is essential for C. albicans pathogenesis; and we discuss its translational implications in antifungal drugs and whole-cell vaccine development.
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Affiliation(s)
- Shraddheya Kumar Patel
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India,Regional center of Biotechnology, Faridabad, India
| | - Satya Ranjan Sahu
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India,Regional center of Biotechnology, Faridabad, India
| | - Bhabasha Gyanadeep Utkalaja
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India,Regional center of Biotechnology, Faridabad, India
| | - Swagata Bose
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India,School of Biotechnology, Kalinga Institute of Industrial Technology, Bhubaneswar, India
| | - Narottam Acharya
- Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India,CONTACT Narottam Acharya ; Laboratory of Genomic Instability and Diseases, Department of Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar751023, India
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5
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Belanger NL, Kim SJ, Bispo PJM. Molecular characterization of fungal endophthalmitis and keratitis caused by yeasts. Med Mycol 2022; 61:myac099. [PMID: 36565720 PMCID: PMC9825281 DOI: 10.1093/mmy/myac099] [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: 08/24/2022] [Revised: 11/11/2022] [Accepted: 12/22/2022] [Indexed: 12/26/2022] Open
Abstract
Candida species are the most common causes of sight-threatening fungal ocular infections in temperate regions of the world. Despite their relevance, little is known about the emergence of novel species and the molecular epidemiology of these infections. Here, we molecularly characterized 38 yeast isolates collected from patients diagnosed with endophthalmitis or keratitis at Massachusetts Eye and Ear from 2014 to 2021. Sequencing of the ITS1-5.8S-/ITS2 regions demonstrated that this population of yeasts was dominated by Candida spp. (37 out of 38; 97%), with 58% of the cases caused by C. albicans (n = 22) and the remaining by emerging non-albicans species, predominantly by C. parapsilosis (n = 8) and C. dubliniensis (n = 6). One isolate each was identified as C. tropicalis and Clavispora lusitaniae. Interestingly, all C. dubliniensis were isolated from endophthalmitis and most C. parapsilosis from keratitis. Multilocus sequence typing analysis of C. albicans showed a prevalence of CC-1 isolates that has DST69 as the putative founder, with 64% of them belonging to this clonal complex (CC). Isolates grouped within this cluster were more predominant in endophthalmitis (10 out of 14; 71%). One C. albicans CC-1 isolate was multi-azole resistant. In conclusion, we observed that nearly half of the ocular infections caused by yeasts are associated with C. albicans, with evidence for the emergence of non-albicans species that are differentially enriched in distinct ocular niches. Candida albicans isolates clustered within the predominant CC-1 group were particularly more common in endophthalmitis, demonstrating a potential pattern of ocular disease enrichment within this clade.
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Affiliation(s)
- Nicole L Belanger
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
| | - Su Jeoung Kim
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
| | - Paulo J M Bispo
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
- Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
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6
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Balaba N, Jaerger S, Horsth DFL, Primo JDO, Correa JDS, Bittencourt C, Zanette CM, Anaissi FJ. Polysaccharides as Green Fuels for the Synthesis of MgO: Characterization and Evaluation of Antimicrobial Activities. MOLECULES (BASEL, SWITZERLAND) 2022; 28:molecules28010142. [PMID: 36615339 PMCID: PMC9822341 DOI: 10.3390/molecules28010142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 12/17/2022] [Accepted: 12/20/2022] [Indexed: 12/28/2022]
Abstract
The synthesis of structured MgO is reported using feedstock starch (route I), citrus pectin (route II), and Aloe vera (route III) leaf, which are suitable for use as green fuels due to their abundance, low cost, and non-toxicity. The oxides formed showed high porosity and were evaluated as antimicrobial agents. The samples were characterized by energy-dispersive X-ray fluorescence (EDXRF), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The crystalline periclase monophase of the MgO was identified for all samples. The SEM analyses show that the sample morphology depends on the organic fuel used during the synthesis. The antibacterial activity of the MgO-St (starch), MgO-CP (citrus pectin), and MgO-Av (Aloe vera) oxides was evaluated against pathogens Staphylococcus aureus (ATCC 6538P) and Escherichia coli (ATCC 8739). Antifungal activity was also studied against Candida albicans (ATCC 64548). The studies were carried out using the qualitative agar disk diffusion method and quantitative minimum inhibitory concentration (MIC) tests. The MIC of each sample showed the same inhibitory concentration of 400 µg. mL-1 for the studied microorganisms. The formation of inhibition zones and the MIC values in the antimicrobial analysis indicate the effective antimicrobial activity of the samples against the test microorganisms.
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Affiliation(s)
- Nayara Balaba
- Departamento de Química, Universidade Estadual do Centro-Oeste, Guarapuava 85040-080, Brazil
| | - Silvia Jaerger
- Departamento de Química, Universidade Estadual do Centro-Oeste, Guarapuava 85040-080, Brazil
| | - Dienifer F. L. Horsth
- Departamento de Química, Universidade Estadual do Centro-Oeste, Guarapuava 85040-080, Brazil
- Chimie des Interactions Plasma-Surface (ChIPS), Research Institute for Materials Science and Engineering, University of Mons, 7000 Mons, Belgium
| | - Julia de O. Primo
- Departamento de Química, Universidade Estadual do Centro-Oeste, Guarapuava 85040-080, Brazil
| | - Jamille de S. Correa
- Departamento de Química, Universidade Estadual do Centro-Oeste, Guarapuava 85040-080, Brazil
| | - Carla Bittencourt
- Chimie des Interactions Plasma-Surface (ChIPS), Research Institute for Materials Science and Engineering, University of Mons, 7000 Mons, Belgium
- Correspondence:
| | - Cristina M. Zanette
- Departamento de Engenharia de Alimentos, Universidade Estadual do Centro-Oeste, Guarapuava 85040-080, Brazil
| | - Fauze J. Anaissi
- Departamento de Química, Universidade Estadual do Centro-Oeste, Guarapuava 85040-080, Brazil
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Antimicrobial activity of some macroalgae of the Veracruzano Reef System (SAV), Mexico. Saudi J Biol Sci 2022; 30:103496. [DOI: 10.1016/j.sjbs.2022.103496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 10/08/2022] [Accepted: 11/07/2022] [Indexed: 11/13/2022] Open
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8
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Lee YS, Chen X, Widiyanto TW, Orihara K, Shibata H, Kajiwara S. Curcumin affects function of Hsp90 and drug efflux pump of Candida albicans. Front Cell Infect Microbiol 2022; 12:944611. [PMID: 36237434 PMCID: PMC9551236 DOI: 10.3389/fcimb.2022.944611] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 09/07/2022] [Indexed: 11/13/2022] Open
Abstract
Candida albicans is a pathogenic yeast that causes candidiasis in immunocompromised patients. The overuse of antifungal drugs has led to the development of resistance to such drugs by this fungus, which is a major challenge in antifungal chemotherapy. One approach to this problem involves the utilization of new natural products as an alternative source of antifungals. Curcumin, one such natural product, has been widely studied as a drug candidate and is reported to exhibit antifungal activity against C. albicans. Although studies of the mechanism of curcumin against human cancer cells have shown that it inhibits heat shock protein 90 (Hsp90), little is known about its function against C. albicans. In this paper, using a doxycycline-mediated HSP90 strain and an HSP90-overexpressing strain of C. albicans, we demonstrated that the curcumin triggered a decrease in Hsp90 by affecting it at the post-transcriptional level. This also led to the downregulation of HOG1 and CDR1, resulting in a reduction of the stress response and efflux pump activity of C. albicans. However, the inhibition of HSP90 by curcumin was not due to the inhibition of transcription factors HSF1 or AHR1. We also found that curcumin can not only decrease the transcriptional expression of CDR1, but also inhibit the efflux pump activity of Cdr1. Hence, we conclude that disruption of HSP90 by curcumin could impair cell growth, stress responses and efflux pump activity of C. albicans.
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Affiliation(s)
- Yean Sheng Lee
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Xinyue Chen
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | | | - Kanami Orihara
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | | | - Susumu Kajiwara
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
- *Correspondence: Susumu Kajiwara,
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Stevenson EM, Gaze WH, Gow NAR, Hart A, Schmidt W, Usher J, Warris A, Wilkinson H, Murray AK. Antifungal Exposure and Resistance Development: Defining Minimal Selective Antifungal Concentrations and Testing Methodologies. FRONTIERS IN FUNGAL BIOLOGY 2022; 3:918717. [PMID: 37746188 PMCID: PMC10512330 DOI: 10.3389/ffunb.2022.918717] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 05/16/2022] [Indexed: 09/26/2023]
Abstract
This scoping review aims to summarise the current understanding of selection for antifungal resistance (AFR) and to compare and contrast this with selection for antibacterial resistance, which has received more research attention. AFR is an emerging global threat to human health, associated with high mortality rates, absence of effective surveillance systems and with few alternative treatment options available. Clinical AFR is well documented, with additional settings increasingly being recognised to play a role in the evolution and spread of AFR. The environment, for example, harbours diverse fungal communities that are regularly exposed to antifungal micropollutants, potentially increasing AFR selection risk. The direct application of effect concentrations of azole fungicides to agricultural crops and the incomplete removal of pharmaceutical antifungals in wastewater treatment systems are of particular concern. Currently, environmental risk assessment (ERA) guidelines do not require assessment of antifungal agents in terms of their ability to drive AFR development, and there are no established experimental tools to determine antifungal selective concentrations. Without data to interpret the selective risk of antifungals, our ability to effectively inform safe environmental thresholds is severely limited. In this review, potential methods to generate antifungal selective concentration data are proposed, informed by approaches used to determine antibacterial minimal selective concentrations. Such data can be considered in the development of regulatory guidelines that aim to reduce selection for AFR.
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Affiliation(s)
- Emily M. Stevenson
- European Centre for Environment and Human Health, University of Exeter Medical School, Cornwall, United Kingdom
- Environment and Sustainability Institute, University of Exeter Medical School, Cornwall, United Kingdom
| | - William H. Gaze
- European Centre for Environment and Human Health, University of Exeter Medical School, Cornwall, United Kingdom
- Environment and Sustainability Institute, University of Exeter Medical School, Cornwall, United Kingdom
| | - Neil A. R. Gow
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Alwyn Hart
- Chief Scientist’s Group, Environment Agency, Horizon House, Bristol, England, United Kingdom
| | - Wiebke Schmidt
- Chief Scientist’s Group, Environment Agency, Horizon House, Bristol, England, United Kingdom
| | - Jane Usher
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Adilia Warris
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Helen Wilkinson
- Chief Scientist’s Group, Environment Agency, Horizon House, Bristol, England, United Kingdom
| | - Aimee K. Murray
- European Centre for Environment and Human Health, University of Exeter Medical School, Cornwall, United Kingdom
- Environment and Sustainability Institute, University of Exeter Medical School, Cornwall, United Kingdom
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Helmstetter N, Chybowska AD, Delaney C, Da Silva Dantas A, Gifford H, Wacker T, Munro C, Warris A, Jones B, Cuomo CA, Wilson D, Ramage G, Farrer RA. Population genetics and microevolution of clinical Candida glabrata reveals recombinant sequence types and hyper-variation within mitochondrial genomes, virulence genes, and drug targets. Genetics 2022; 221:iyac031. [PMID: 35199143 PMCID: PMC9071574 DOI: 10.1093/genetics/iyac031] [Citation(s) in RCA: 10] [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: 01/05/2022] [Accepted: 02/16/2022] [Indexed: 12/02/2022] Open
Abstract
Candida glabrata is the second most common etiological cause of worldwide systemic candidiasis in adult patients. Genome analysis of 68 isolates from 8 hospitals across Scotland, together with 83 global isolates, revealed insights into the population genetics and evolution of C. glabrata. Clinical isolates of C. glabrata from across Scotland are highly genetically diverse, including at least 19 separate sequence types that have been recovered previously in globally diverse locations, and 1 newly discovered sequence type. Several sequence types had evidence for ancestral recombination, suggesting transmission between distinct geographical regions has coincided with genetic exchange arising in new clades. Three isolates were missing MATα1, potentially representing a second mating type. Signatures of positive selection were identified in every sequence type including enrichment for epithelial adhesins thought to facilitate fungal adhesin to human epithelial cells. In patent microevolution was identified from 7 sets of recurrent cases of candidiasis, revealing an enrichment for nonsynonymous and frameshift indels in cell surface proteins. Microevolution within patients also affected epithelial adhesins genes, and several genes involved in drug resistance including the ergosterol synthesis gene ERG4 and the echinocandin target FKS1/2, the latter coinciding with a marked drop in fluconazole minimum inhibitory concentration. In addition to nuclear genome diversity, the C. glabrata mitochondrial genome was particularly diverse, with reduced conserved sequence and conserved protein-encoding genes in all nonreference ST15 isolates. Together, this study highlights the genetic diversity within the C. glabrata population that may impact virulence and drug resistance, and 2 major mechanisms generating this diversity: microevolution and genetic exchange/recombination.
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Affiliation(s)
- Nicolas Helmstetter
- Medical Research Council, Centre for Medical Mycology, University of Exeter, Exeter EX4 4QD UK
| | | | - Christopher Delaney
- School of Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | | | - Hugh Gifford
- Medical Research Council, Centre for Medical Mycology, University of Exeter, Exeter EX4 4QD UK
| | - Theresa Wacker
- Medical Research Council, Centre for Medical Mycology, University of Exeter, Exeter EX4 4QD UK
| | - Carol Munro
- Institute of Medical Sciences, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - Adilia Warris
- Medical Research Council, Centre for Medical Mycology, University of Exeter, Exeter EX4 4QD UK
| | - Brian Jones
- Institute of Infection, Immunity & Inflammation, University of Glasgow, Glasgow G12 8TA, UK
| | | | - Duncan Wilson
- Medical Research Council, Centre for Medical Mycology, University of Exeter, Exeter EX4 4QD UK
| | - Gordon Ramage
- School of Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Rhys A Farrer
- Medical Research Council, Centre for Medical Mycology, University of Exeter, Exeter EX4 4QD UK
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
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Prasad P, Joshi A, Ghosh SK. Sth1, the ATPase subunit of the RSC chromatin remodeler has important roles in stress response and DNA damage repair in the pathogenic fungi Candida albicans. Microb Pathog 2022; 166:105515. [DOI: 10.1016/j.micpath.2022.105515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 03/26/2022] [Accepted: 04/03/2022] [Indexed: 01/13/2023]
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Razzaq I, Berg MD, Jiang Y, Genereaux J, Uthayakumar D, Kim GH, Agyare-Tabbi M, Halder V, Brandl CJ, Lajoie P, Shapiro RS. The SAGA and NuA4 component Tra1 regulates Candida albicans drug resistance and pathogenesis. Genetics 2021; 219:iyab131. [PMID: 34849885 PMCID: PMC8633099 DOI: 10.1093/genetics/iyab131] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/02/2021] [Indexed: 11/14/2022] Open
Abstract
Candida albicans is the most common cause of death from fungal infections. The emergence of resistant strains reducing the efficacy of first-line therapy with echinocandins, such as caspofungin calls for the identification of alternative therapeutic strategies. Tra1 is an essential component of the SAGA and NuA4 transcriptional co-activator complexes. As a PIKK family member, Tra1 is characterized by a C-terminal phosphoinositide 3-kinase domain. In Saccharomyces cerevisiae, the assembly and function of SAGA and NuA4 are compromised by a Tra1 variant (Tra1Q3) with three arginine residues in the putative ATP-binding cleft changed to glutamine. Whole transcriptome analysis of the S. cerevisiae tra1Q3 strain highlights Tra1's role in global transcription, stress response, and cell wall integrity. As a result, tra1Q3 increases susceptibility to multiple stressors, including caspofungin. Moreover, the same tra1Q3 allele in the pathogenic yeast C. albicans causes similar phenotypes, suggesting that Tra1 broadly mediates the antifungal response across yeast species. Transcriptional profiling in C. albicans identified 68 genes that were differentially expressed when the tra1Q3 strain was treated with caspofungin, as compared to gene expression changes induced by either tra1Q3 or caspofungin alone. Included in this set were genes involved in cell wall maintenance, adhesion, and filamentous growth. Indeed, the tra1Q3 allele reduces filamentation and other pathogenesis traits in C. albicans. Thus, Tra1 emerges as a promising therapeutic target for fungal infections.
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Affiliation(s)
- Iqra Razzaq
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G2W1, Canada
| | - Matthew D Berg
- Department of Biochemistry, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - Yuwei Jiang
- Department of Anatomy and Cell Biology, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - Julie Genereaux
- Department of Biochemistry, The University of Western Ontario, London, ON N6A 5C1, Canada
- Department of Anatomy and Cell Biology, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - Deeva Uthayakumar
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G2W1, Canada
| | - Grace H Kim
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G2W1, Canada
| | - Michelle Agyare-Tabbi
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G2W1, Canada
| | - Viola Halder
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G2W1, Canada
| | - Christopher J Brandl
- Department of Biochemistry, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - Patrick Lajoie
- Department of Anatomy and Cell Biology, The University of Western Ontario, London, ON N6A 5C1, Canada
| | - Rebecca S Shapiro
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G2W1, Canada
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13
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Chen X, Zhang H, Wang X, Shao Z, Li Y, Zhao G, Liu F, Liu B, Zheng Y, Chen T, Zheng H, Zhang L, Gao C. OTUD1 Regulates Antifungal Innate Immunity through Deubiquitination of CARD9. THE JOURNAL OF IMMUNOLOGY 2021; 206:1832-1843. [PMID: 33789983 DOI: 10.4049/jimmunol.2001253] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 02/08/2021] [Indexed: 12/30/2022]
Abstract
CARD9 is an essential adaptor protein in antifungal innate immunity mediated by C-type lectin receptors. The activity of CARD9 is critically regulated by ubiquitination; however, the deubiquitinases involved in CARD9 regulation remain incompletely understood. In this study, we identified ovarian tumor deubiquitinase 1 (OTUD1) as an essential regulator of CARD9. OTUD1 directly interacted with CARD9 and cleaved polyubiquitin chains from CARD9, leading to the activation of the canonical NF-κB and MAPK pathway. OTUD1 deficiency impaired CARD9-mediated signaling and inhibited the proinflammatory cytokine production following fungal stimulation. Importantly, Otud1 -/- mice were more susceptible to fungal infection than wild-type mice in vivo. Collectively, our results identify OTUD1 as an essential regulatory component for the CARD9 signaling pathway and antifungal innate immunity through deubiquitinating CARD9.
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Affiliation(s)
- Xiaorong Chen
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China
| | - Honghai Zhang
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China
| | - Xueer Wang
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China
| | - Zhugui Shao
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China
| | - Yanqi Li
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China
| | - Guimin Zhao
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China
| | - Feng Liu
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China
| | - Bingyu Liu
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China
| | - Yi Zheng
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China
| | - Tian Chen
- Department of Pathogenic Biology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China; and
| | - Hui Zheng
- International Institute of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, 215123 Suzhou, Jiangsu, People's Republic of China
| | - Lei Zhang
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China;
| | - Chengjiang Gao
- Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Biomedical Sciences, Shandong University, 250012 Jinan, Shandong, People's Republic of China;
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14
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Huang X, Liu Y, Ni T, Li L, Yan L, An M, Zhang D, Jiang Y. 11g, a Potent Antifungal Candidate, Enhances Candida albicans Immunogenicity by Unmasking β-Glucan in Fungal Cell Wall. Front Microbiol 2020; 11:1324. [PMID: 32695076 PMCID: PMC7338940 DOI: 10.3389/fmicb.2020.01324] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 05/25/2020] [Indexed: 12/14/2022] Open
Abstract
In the course of optimizing GPI biosynthesis inhibitors, we designed and synthetized a 2-aminonicotinamide derivative named 11g. After evaluating the antifungal activity of compound 11g in vitro, we investigated the influences of 11g on fungi immunogenicity. In addition, we also took advantage of murine systemic candidiasis model to investigate the protective effects of 11g in vivo. Results show that 11g exhibited potent antifungal activity both in vitro and in vivo. Further study shows that 11g caused the unmasking of fungi β-glucan layer, leading to stronger immune responses in macrophages through Dectin-1. These results suggest that 11g is a very promising antifungal candidate, which assists in eliciting stronger immune responses to help host immune system disposing pathogens. The discovery of 11g might expand the toolbox of fungal infection treatment.
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Affiliation(s)
- Xin Huang
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | - Yu Liu
- School of Pharmacy, Second Military Medical University, Shanghai, China
| | - Tingjunhong Ni
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | - Liping Li
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | - Lan Yan
- School of Pharmacy, Second Military Medical University, Shanghai, China
| | - Maomao An
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | - Dazhi Zhang
- School of Pharmacy, Second Military Medical University, Shanghai, China
| | - Yuanying Jiang
- Department of Pharmacology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China.,School of Pharmacy, Second Military Medical University, Shanghai, China
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15
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Park M, Cho YJ, Lee YW, Jung WH. Genomic Multiplication and Drug Efflux Influence Ketoconazole Resistance in Malassezia restricta. Front Cell Infect Microbiol 2020; 10:191. [PMID: 32426297 PMCID: PMC7203472 DOI: 10.3389/fcimb.2020.00191] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 04/09/2020] [Indexed: 12/24/2022] Open
Abstract
Malassezia restricta is an opportunistic fungal pathogen on human skin; it is associated with various skin diseases, including seborrheic dermatitis and dandruff, which are usually treated using ketoconazole. In this study, we clinically isolated ketoconazole-resistant M. restricta strains (KCTC 27529 and KCTC 27550) from patients with dandruff. To understand the mechanisms of ketoconazole resistance in the isolates, their genomes were sequenced and compared with the susceptible reference strain M. restricta KCTC 27527. Using comparative genome analysis, we identified tandem multiplications of the genomic loci containing ATM1 and ERG11 homologs in M. restricta KCTC 27529 and KCTC 27550, respectively. Additionally, we found that the copy number increase of ATM1 and ERG11 is reflected in the increased expression of these genes; moreover, we observed that overexpression of these homologs caused ketoconazole resistance in a genetically tractable fungal pathogen, Cryptococcus neoformans. In addition to tandem multiplications of the genomic region containing the ATM1 homolog, the PDR5 homolog, which encodes the drug efflux pump protein was upregulated in M. restricta KCTC 27529 compared to the reference strain. Biochemical analysis confirmed that drug efflux was highly activated in M. restricta KCTC 27529, implying that upregulation of the PDR5 homolog may also contribute to ketoconazole resistance in the strain. Overall, our results suggest that multiplication of the genomic loci encoding genes involved in ergosterol synthesis, mitochondrial iron metabolism, and oxidative stress response and overexpression of the drug efflux pumps are the mechanisms underlying ketoconazole resistance in M. restricta.
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Affiliation(s)
- Minji Park
- Department of Systems Biotechnology, Chung-Ang University, Anseong, South Korea
| | - Yong-Joon Cho
- School of Biological Sciences and Research Institute of Basic Sciences, Seoul National University, Seoul, South Korea
| | - Yang Won Lee
- Department of Dermatology, School of Medicine, Konkuk University, Seoul, South Korea.,Research Institute of Medicine, Konkuk University, Seoul, South Korea
| | - Won Hee Jung
- Department of Systems Biotechnology, Chung-Ang University, Anseong, South Korea
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16
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Tilocca B, Cao A, Migheli Q. Scent of a Killer: Microbial Volatilome and Its Role in the Biological Control of Plant Pathogens. Front Microbiol 2020; 11:41. [PMID: 32117096 PMCID: PMC7018762 DOI: 10.3389/fmicb.2020.00041] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 01/09/2020] [Indexed: 11/29/2022] Open
Abstract
The use of synthetic fungicides represents the most common strategy to control plant pathogens. Excessive and/or long-term distribution of chemicals is responsible for increased levels of environmental pollution, as well as adverse health consequence to humans and animals. These issues are deeply influencing public perception, as reflected by the increasing demand for safer and eco-friendly agricultural commodities and their by-products. A steadily increasing number of research efforts is now devoted to explore the use of safer and innovative approaches to control plant pathogens. The use of microorganisms as biological control agents (BCAs) represents one of the most durable and promising strategies. Among the panoply of microbial mechanisms exerted by BCAs, the production of volatile organic compounds (VOCs) represents an intriguing issue, mostly exploitable in circumstances where a direct contact between the pathogen and its antagonist is not practicable. VOCs are potentially produced by all living microorganisms, and may be active in the biocontrol of phytopathogenic oomycetes, fungi, and bacteria by means of antimicrobial activity and/or other cross-talk interactions. Their biological effects, the reduced residuals in the environment and on agricultural commodities, and the ease of application in different agricultural systems make the use of VOCs a promising and sustainable approach to replace synthetic fungicides in the control of plant pathogens. In this review, we focus on VOCs produced by bacteria and fungi and on their role in the cross-talk existing between the plant pathogens and their host. Biologic systemic effect of the microbial volatile blends on both pathogen and host plant cells is also briefly reviewed.
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Affiliation(s)
- Bruno Tilocca
- Department of Health Sciences, University “Magna Græcia” of Catanzaro, Catanzaro, Italy
- Dipartimento di Agraria and NRD-Nucleo di Ricerca sulla Desertificazione, Università degli Studi di Sassari, Sassari, Italy
| | - Aocheng Cao
- Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Quirico Migheli
- Dipartimento di Agraria and NRD-Nucleo di Ricerca sulla Desertificazione, Università degli Studi di Sassari, Sassari, Italy
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17
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Osmond MM, Otto SP, Martin G. Genetic Paths to Evolutionary Rescue and the Distribution of Fitness Effects Along Them. Genetics 2020; 214:493-510. [PMID: 31822480 PMCID: PMC7017017 DOI: 10.1534/genetics.119.302890] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Accepted: 12/06/2019] [Indexed: 02/07/2023] Open
Abstract
The past century has seen substantial theoretical and empirical progress on the genetic basis of adaptation. Over this same period, a pressing need to prevent the evolution of drug resistance has uncovered much about the potential genetic basis of persistence in declining populations. However, we have little theory to predict and generalize how persistence-by sufficiently rapid adaptation-might be realized in this explicitly demographic scenario. Here, we use Fisher's geometric model with absolute fitness to begin a line of theoretical inquiry into the genetic basis of evolutionary rescue, focusing here on asexual populations that adapt through de novo mutations. We show how the dominant genetic path to rescue switches from a single mutation to multiple as mutation rates and the severity of the environmental change increase. In multi-step rescue, intermediate genotypes that themselves go extinct provide a "springboard" to rescue genotypes. Comparing to a scenario where persistence is assured, our approach allows us to quantify how a race between evolution and extinction leads to a genetic basis of adaptation that is composed of fewer loci of larger effect. We hope this work brings awareness to the impact of demography on the genetic basis of adaptation.
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Affiliation(s)
- Matthew M Osmond
- Biodiversity Centre and Department of Zoology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Sarah P Otto
- Biodiversity Centre and Department of Zoology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Guillaume Martin
- Institut des Sciences de l'Evolution de Montpellier UMR5554, Universite de Montpellier, CNRS-IRD-EPHE-UM, France
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18
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Could Fungicides Lead to Azole Drug Resistance in a Cross-Resistance Manner among Environmental Cryptococcus Strains? CURRENT FUNGAL INFECTION REPORTS 2020. [DOI: 10.1007/s12281-020-00373-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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19
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Anticandidal agent for multiple targets: the next paradigm in the discovery of proficient therapeutics/overcoming drug resistance. Future Med Chem 2019; 11:2955-2974. [DOI: 10.4155/fmc-2018-0479] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Candida albicans is a prominent human fungal pathogen. Current treatments are suffering a massive gap due to emerging resistance against available antifungals. Therefore, there is an ardent need for novel antifungal candidates that essentially have more than one target, as most antifungal repertoires are single-target drugs. Exploration of multiple-drug targeting in antifungal therapeutics is still pending. An extensive literature survey was performed to categorize and comprehend relevant studies and the current therapeutic scenario that led researchers to preferentially consider multitarget drug-based Candida infection therapy. With this article, we identified and compiled a few potent antifungal compounds that are directed toward multiple virulent targets in C. albicans. Such compound(s) provide an optimistic platform of multiple targeting and could leave a substantial impact on the development of effective antifungals.
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20
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A comparative evaluation of antimicrobial activity of chitooligosaccharides with broad spectrum antibiotics on growth of some pathogenic microorganisms. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.101382] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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21
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Effect of photodynamic antimicrobial chemotherapy on Candida albicans in the presence of glucose. Photodiagnosis Photodyn Ther 2019; 27:54-58. [DOI: 10.1016/j.pdpdt.2019.05.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 05/19/2019] [Accepted: 05/24/2019] [Indexed: 11/22/2022]
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22
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Prasad P, Sanyal K, Ghosh SK. Sth1, the Key Subunit of the RSC Chromatin Remodeling Complex, Is Essential in Maintaining Chromosomal Integrity and Mediating High Fidelity Chromosome Segregation in the Human Fungal Pathogen Candida albicans. Front Microbiol 2019; 10:1303. [PMID: 31249561 PMCID: PMC6582774 DOI: 10.3389/fmicb.2019.01303] [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: 01/13/2019] [Accepted: 05/27/2019] [Indexed: 12/20/2022] Open
Abstract
Chromatin architecture influences gene expression and makes specialized chromatin domains. Factors including histone variants, histone modifiers and chromatin remodelers that define chromatin architecture impact chromosome related processes in Candida albicans. In this context, we sought to investigate the roles of the ATP-dependent chromatin remodeler, Remodel the Structure of Chromatin (RSC) in chromosome segregation of C. albicans. Sth1 is the key ATPase component of RSC and has profound roles in different cellular processes in Saccharomyces cerevisiae. We demonstrate that STH1 is an essential gene in C. albicans. The depletion of Sth1 induces pseudohyphal cells, abnormal spindle morphology, sensitivity toward anti-mitotic drugs and global cohesion defect suggesting an important role of Sth1 in kinetochore-microtubule related processes in C. albicans. Strikingly, Sth1 is required to maintain clustered kinetochores revealing the fact that RSC is required in kinetochore integrity. Taken together, we show that RSC plays an important role in various chromatin-templated processes including chromosome segregation in C. albicans.
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Affiliation(s)
- Priya Prasad
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India
| | - Kaustuv Sanyal
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Santanu K Ghosh
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, India
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23
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Loh JT, Xu S, Huo JX, Kim SSY, Wang Y, Lam KP. Dok3-protein phosphatase 1 interaction attenuates Card9 signaling and neutrophil-dependent antifungal immunity. J Clin Invest 2019; 129:2717-2729. [PMID: 31180338 DOI: 10.1172/jci126341] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 04/25/2019] [Indexed: 12/29/2022] Open
Abstract
Invasive fungal infection is a serious health threat with high morbidity and mortality. Current antifungal drugs only demonstrate partial success in improving prognosis. Furthermore, mechanisms regulating host defense against fungal pathogens remain elusive. Here, we report that the downstream of kinase 3 (Dok3) adaptor negatively regulates antifungal immunity in neutrophils. Our data revealed that Dok3 deficiency increased phagocytosis, proinflammatory cytokine production, and netosis in neutrophils, thereby enhancing mutant mouse survival against systemic infection with a lethal dose of the pathogenic fungus Candida albicans. Biochemically, Dok3 recruited protein phosphatase 1 (PP1) to dephosphorylate Card9, an essential player in innate antifungal defense, to dampen downstream NF-κB and JNK activation and immune responses. Thus, Dok3 suppresses Card9 signaling, and disrupting Dok3-Card9 interaction or inhibiting PP1 activity represents therapeutic opportunities to develop drugs to combat candidaemia.
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Affiliation(s)
- Jia Tong Loh
- Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore
| | - Shengli Xu
- Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Jian Xin Huo
- Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore
| | - Susana Soo-Yeon Kim
- Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore
| | - Yue Wang
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore.,Department of Biochemistry and
| | - Kong-Peng Lam
- Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore.,Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,School of Biological Sciences, College of Science, Nanyang Technological University, Singapore
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24
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Can Saccharomyces cerevisiae keep up as a model system in fungal azole susceptibility research? Drug Resist Updat 2019; 42:22-34. [PMID: 30822675 DOI: 10.1016/j.drup.2019.02.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/30/2019] [Accepted: 02/11/2019] [Indexed: 12/14/2022]
Abstract
The difficulty of manipulation and limited availability of genetic tools for use in many pathogenic fungi hamper fast and adequate investigation of cellular metabolism and consequent possibilities for antifungal therapies. S. cerevisiae is a model organism that is used to study many eukaryotic systems. In this review, we analyse the potency and relevance of this model system in investigating fungal susceptibility to azole drugs. Although many of the concepts apply to multiple pathogenic fungi, for the sake of simplicity, we will focus on the validity of using S. cerevisiae as a model organism for two Candida species, C. albicans and C. glabrata. Apart from the general benefits, we explore how S. cerevisiae can specifically be used to improve our knowledge on azole drug resistance and enables fast and efficient screening for novel drug targets in combinatorial therapy. We consider the shortcomings of the model system, yet conclude that it is still opportune to use S. cerevisiae as a model system for pathogenic fungi in this era.
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25
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Ksiezopolska E, Gabaldón T. Evolutionary Emergence of Drug Resistance in Candida Opportunistic Pathogens. Genes (Basel) 2018; 9:genes9090461. [PMID: 30235884 PMCID: PMC6162425 DOI: 10.3390/genes9090461] [Citation(s) in RCA: 114] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 09/14/2018] [Accepted: 09/17/2018] [Indexed: 01/08/2023] Open
Abstract
Fungal infections, such as candidiasis caused by Candida, pose a problem of growing medical concern. In developed countries, the incidence of Candida infections is increasing due to the higher survival of susceptible populations, such as immunocompromised patients or the elderly. Existing treatment options are limited to few antifungal drug families with efficacies that vary depending on the infecting species. In this context, the emergence and spread of resistant Candida isolates are being increasingly reported. Understanding how resistance can evolve within naturally susceptible species is key to developing novel, more effective treatment strategies. However, in contrast to the situation of antibiotic resistance in bacteria, few studies have focused on the evolutionary mechanisms leading to drug resistance in fungal species. In this review, we will survey and discuss current knowledge on the genetic bases of resistance to antifungal drugs in Candida opportunistic pathogens. We will do so from an evolutionary genomics perspective, focusing on the possible evolutionary paths that may lead to the emergence and selection of the resistant phenotype. Finally, we will discuss the potential of future studies enabled by current developments in sequencing technologies, in vitro evolution approaches, and the analysis of serial clinical isolates.
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Affiliation(s)
- Ewa Ksiezopolska
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), 08003 Barcelona, Spain.
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain.
| | - Toni Gabaldón
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), 08003 Barcelona, Spain.
- Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain.
- Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain.
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26
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Iron Restriction to Clinical Isolates of Candida albicans by the Novel Chelator DIBI Inhibits Growth and Increases Sensitivity to Azoles In Vitro and In Vivo in a Murine Model of Experimental Vaginitis. Antimicrob Agents Chemother 2018; 62:AAC.02576-17. [PMID: 29844048 DOI: 10.1128/aac.02576-17] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 05/19/2018] [Indexed: 12/22/2022] Open
Abstract
Candida albicans is an important opportunistic pathogen causing various human infections that are often treated with azole antifungals. The U.S. CDC now regards developing candidal antifungal resistance as a threat, creating a need for new and more effective antifungal treatments. Iron is an essential nutrient for all living cells, and there is growing evidence that interference with iron homeostasis of C. albicans can improve its response to antifungals. This study was aimed at establishing whether withholding iron by currently used medical iron chelators and the novel chelator DIBI could restrict growth and also enhance the activity of azoles against clinical isolates of C. albicans DIBI, but not deferoxamine or deferiprone, inhibited the growth of C. albicans at relatively low concentrations in vitro, and this inhibition was reversed by iron addition. DIBI in combination with various azoles demonstrated stronger growth inhibition than the azoles alone and greatly prolonged the inhibition of cell multiplication. In addition, the administration of DIBI along with fluconazole (FLC) to mice inoculated with an FLC-sensitive isolate in a model of experimental C. albicans vaginitis showed a markedly improved clearance of infection. These results suggest that iron chelation by DIBI has the potential to enhance azole efficacy for the treatment of candidiasis.
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27
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Wang C, Yang Z, Peng Y, Guo Y, Yao M, Dong J. Application of 460 nm visible light for the elimination of Candida albicans in vitro and in vivo. Mol Med Rep 2018; 18:2017-2026. [PMID: 29956765 PMCID: PMC6072199 DOI: 10.3892/mmr.2018.9196] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 05/23/2018] [Indexed: 01/23/2023] Open
Abstract
The aim of the present study was to investigate the eradicating effects of 460 nm blue light (BL) on Candida albicans in vitro and in C. albicans-infected skin wounds in a mouse model. In the present study, the antifungal effects of irradiation with BL on C. albicans in vitro and in vivo were investigated. C. albicans colonies and cell numbers were investigated using the spread plate method and flow cytometry respectively following treatment with BL irradiation. In order to determine whether BL can eradicate C. albicans cells within biofilms, an in vitro C. albicans biofilm model was established, and the effect of BL was subsequently investigated using a confocal laser scanning microscope and a Live/Dead staining kit. Furthermore, a mouse skin wound infection model infected with C. albicans was established. Wound healing rates and histological examinations were determined 0, 3, 7, 10 and 14 days post-wounding. The results revealed that C. albicans was eradicated by BL in a dose-dependent manner, with a minimum fluence of 60 J/cm2. Irradiation with BL almost completely eradicated C. albicans when the light fluence was 240 J/cm2. C. albicans inside biofilms was also eradicated and biofilms were destroyed following BL irradiation at 240 J/cm2. In addition, BL was revealed to significantly suppress C. albicans infection in vivo. Irradiation with BL promoted the wound healing of C. albicans infected-skin wounds in a mouse model. In conclusion, the results of the present study demonstrated that 460 nm BL may eradicate planktonic and biofilm C. albicans in vitro, and represents a novel therapeutic strategy for the treatment of C. albicans infections in vivo.
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Affiliation(s)
- Chuan Wang
- Department of Burns and Plastic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, P.R. China
| | - Zhiyin Yang
- Department of Thoracic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, P.R. China
| | - Yinbo Peng
- Department of Burns and Plastic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, P.R. China
| | - Yuanyuan Guo
- Department of Urology, First Affiliated Hospital of Bengbu Medical College, Bengbu, Anhui 233000, P.R. China
| | - Min Yao
- Department of Burns and Plastic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, P.R. China
| | - Jiying Dong
- Department of Burns and Plastic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201999, P.R. China
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Stawowczyk M, Naseem S, Montoya V, Baker DP, Konopka J, Reich NC. Pathogenic Effects of IFIT2 and Interferon-β during Fatal Systemic Candida albicans Infection. mBio 2018; 9:e00365-18. [PMID: 29666281 PMCID: PMC5904408 DOI: 10.1128/mbio.00365-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 03/21/2018] [Indexed: 01/01/2023] Open
Abstract
A balanced immune response to infection is essential to prevent the pathology and tissue damage that can occur from an unregulated or hyperactive host defense. Interferons (IFNs) are critical mediators of the innate defense to infection, and in this study we evaluated the contribution of a specific gene coding for IFIT2 induced by type I IFNs in a murine model of disseminated Candida albicans Invasive candidiasis is a frequent challenge during immunosuppression or surgical medical interventions, and C. albicans is a common culprit that leads to high rates of mortality. When IFIT2 knockout mice were infected systemically with C. albicans, they were found to have improved survival and reduced fungal burden compared to wild-type mice. One of the mechanisms by which IFIT2 increases the pathological effects of invasive C. albicans appears to be suppression of NADPH oxidase activation. Loss of IFIT2 increases production of reactive oxygen species by leukocytes, and we demonstrate that IFIT2 is a binding partner of a critical regulatory subunit of NADPH oxidase, p67phox Since the administration of IFN has been used therapeutically to combat viral infections, cancer, and multiple sclerosis, we evaluated administration of IFN-β to mice prior to C. albicans infection. IFN-β treatment promoted pathology and death from C. albicans infection. We provide evidence that IFIT2 increases the pathological effects of invasive C. albicans and that administration of IFN-β has deleterious effects during infection.IMPORTANCE The attributable mortality associated with systemic C. albicans infections in health care settings is significant, with estimates greater than 40%. This life-threatening disease is common in patients with weakened immune systems, either due to disease or as a result of therapies. Type I interferons (IFN) are cytokines of the innate defense response that are used as immune modulators in the treatment of specific cancers, viral infections, and multiple sclerosis. In this study, we show using a murine model that the loss of a specific IFN-stimulated gene coding for IFIT2 improves survival following systemic C. albicans infection. This result infers a harmful effect of IFN during C. albicans infection and is supported by our finding that administration of IFN-β prior to invasive infection promotes fatal pathology. The findings contribute to our understanding of the innate immune response to C. albicans, and they suggest that IFN therapies present a risk factor for disseminated candidiasis.
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Affiliation(s)
- Marcin Stawowczyk
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - Shamoon Naseem
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - Valeria Montoya
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | | | - James Konopka
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - Nancy C Reich
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
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Integrated transcriptomic analysis of Trichosporon Asahii uncovers the core genes and pathways of fluconazole resistance. Sci Rep 2017; 7:17847. [PMID: 29259317 PMCID: PMC5736589 DOI: 10.1038/s41598-017-18072-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 12/05/2017] [Indexed: 12/15/2022] Open
Abstract
Trichosporon asahii (T. asahii) has emerged as a dangerous pathogen that causes rare but life-threatening infections. Its resistance to certain antifungal agents makes it difficult to treat, especially for patients undergoing long-term antibiotic therapy. In this study, we performed a series of fluconazole (FLC) perturbation experiments for two T. asahii strains, a clinical isolate stain CBS 2479 (T2) and an environmental isolate strain CBS 8904 (T8), to uncover potential genes and pathways involved in FLC resistance. We achieved 10 transcriptomes of T2 and T8 that were based on dose and time series of FLC perturbations. Systematic comparisons of the transcriptomes revealed 32 T2 genes and 25 T8 genes that are highly sensitive to different FLC perturbations. In both T2 and T8 strains with the phenotype of FLC resistance, the processes of oxidation-reduction and transmembrane transport were detected to be significantly changed. The antifungal susceptibility testing of FLC and penicillin revealed their resistance pathways are merged. Accumulated mutations were found in 564 T2 and 225 T8 genes, including four highly mutated genes that are functionally related to the target of rapamycin complex (TOR). Our study provides abundant data towards genome-wide understanding of the molecular basis of FLC resistance in T. asahii.
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Feng W, Yang J, Xi Z, Qiao Z, Lv Y, Wang Y, Ma Y, Wang Y, Cen W. Mutations and/or Overexpressions ofERG4andERG11Genes in Clinical Azoles-Resistant Isolates ofCandida albicans. Microb Drug Resist 2017; 23:563-570. [PMID: 27976986 DOI: 10.1089/mdr.2016.0095] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Wenli Feng
- Department of Dermatovenereology, The Second Hospital of Shanxi Medical University, Taiyuan City, Shanxi Province, China
| | - Jing Yang
- Department of Dermatovenereology, The Second Hospital of Shanxi Medical University, Taiyuan City, Shanxi Province, China
| | - Zhiqin Xi
- Department of Dermatovenereology, The Second Hospital of Shanxi Medical University, Taiyuan City, Shanxi Province, China
| | - Zusha Qiao
- Department of Dermatovenereology, The Second Hospital of Shanxi Medical University, Taiyuan City, Shanxi Province, China
| | - Yaping Lv
- Department of Dermatovenereology, The Second Hospital of Shanxi Medical University, Taiyuan City, Shanxi Province, China
| | - Yiru Wang
- Department of Dermatovenereology, The Second Hospital of Shanxi Medical University, Taiyuan City, Shanxi Province, China
| | - Yan Ma
- Department of Dermatovenereology, The Second Hospital of Shanxi Medical University, Taiyuan City, Shanxi Province, China
| | - Yanqing Wang
- Department of Dermatovenereology, The Second Hospital of Shanxi Medical University, Taiyuan City, Shanxi Province, China
| | - Wen Cen
- Department of Dermatovenereology, The Second Hospital of Shanxi Medical University, Taiyuan City, Shanxi Province, China
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Zinc Cluster Transcription Factors Alter Virulence in Candida albicans. Genetics 2016; 205:559-576. [PMID: 27932543 DOI: 10.1534/genetics.116.195024] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 11/16/2016] [Indexed: 11/18/2022] Open
Abstract
Almost all humans are colonized with Candida albicans However, in immunocompromised individuals, this benign commensal organism becomes a serious, life-threatening pathogen. Here, we describe and analyze the regulatory networks that modulate innate responses in the host niches. We identified Zcf15 and Zcf29, two Zinc Cluster transcription Factors (ZCF) that are required for C. albicans virulence. Previous sequence analysis of clinical C. albicans isolates from immunocompromised patients indicates that both ZCF genes diverged during clonal evolution. Using in vivo animal models, ex vivo cell culture methods, and in vitro sensitivity assays, we demonstrate that knockout mutants of both ZCF15 and ZCF29 are hypersensitive to reactive oxygen species (ROS), suggesting they help neutralize the host-derived ROS produced by phagocytes, as well as establish a sustained infection in vivo Transcriptomic analysis of mutants under resting conditions where cells were not experiencing oxidative stress revealed a large network that control macro and micronutrient homeostasis, which likely contributes to overall pathogen fitness in host niches. Under oxidative stress, both transcription factors regulate a separate set of genes involved in detoxification of ROS and down-regulating ribosome biogenesis. ChIP-seq analysis, which reveals vastly different binding partners for each transcription factor (TF) before and after oxidative stress, further confirms these results. Furthermore, the absence of a dominant binding motif likely facilitates their mobility, and supports the notion that they represent a recent expansion of the ZCF family in the pathogenic Candida species. Our analyses provide a framework for understanding new aspects of the interface between C. albicans and host defense response, and extends our understanding of how complex cell behaviors are linked to the evolution of TFs.
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Genotyping and Persistence of Candida albicans from Pregnant Women with Vulvovaginal Candidiasis. Mycopathologia 2016; 182:339-347. [PMID: 27882525 DOI: 10.1007/s11046-016-0095-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 11/16/2016] [Indexed: 01/29/2023]
Abstract
OBJECTIVE To study Candida albicans genotypes using RAPD and their susceptibility to fluconazole in healthy pregnant women and in vulvovaginal candidiasis (VVC) patients after topical treatment with clotrimazole. METHODS Vaginal swabs were collected at t = 0 and t = 1 (1 month later) in pregnant women (control group, n = 33), and before (t = 0), at 1 month (t = 1) and at 2 months (t = 2) after clotrimazole treatment in pregnant women with VVC. RESULTS Candida albicans was isolated in 30% of healthy pregnant women and 80% of patients with VVC. A high genetic heterogeneity was observed in C. albicans genotypes between individuals. In patients with VVC, topical antifungal treatment with clotrimazole was clinically effective, but only in a 62% C. albicans was eradicated. In patients in which C. albicans was not eradicated, this microorganism persisted for 1 or 2 months after the antifungal treatment. The persistent colonies were not associated with a specific genotype, but they were associated with higher MICs in comparison with colonies isolated from the control group. CONCLUSIONS Therapy with topical clotrimazole, despite a good clinical outcome, could not eradicate completely C. albicans allowing the persistence of genotypes, with higher MICs to fluconazole. More studies with higher number of patients are needed to validate this preliminary finding.
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Barbosa GM, Dos Santos EG, Capella FNC, Homsani F, de Pointis Marçal C, Dos Santos Valle R, de Araújo Abi-Chacra É, Braga-Silva LA, de Oliveira Sales MH, da Silva Neto ID, da Veiga VF, Dos Santos ALS, Holandino C. Direct electric current modifies important cellular aspects and ultrastructure features of Candida albicans yeasts: Influence of doses and polarities. Bioelectromagnetics 2016; 38:95-108. [PMID: 27783424 DOI: 10.1002/bem.22015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 10/07/2016] [Indexed: 11/09/2022]
Abstract
Available treatments against human fungal pathogens present high levels of resistance, motivating the development of new antifungal therapies. In this context, the present work aimed to analyze direct electric current (DC) antifungal action, using an in vitro apparatus equipped with platinum electrodes. Candida albicans yeast cells were submitted to three distinct conditions of DC treatment (anodic flow-AF; electroionic flow-EIF; and cathodic flow-CF), as well as different charges, ranging from 0.03 to 2.40 C. Our results indicated C. albicans presented distinct sensibility depending on the DC intensity and polarity applied. Both the colony-forming unit assay and the cytometry flow with propidium iodide indicated a drastic reduction on cellular viability after AF treatment with 0.15 C, while CF- and EIF-treated cells stayed alive when DC doses were increased up to 2.40 C. Additionally, transmission electron microscopy revealed important ultrastructural alterations in AF-treated yeasts, including cell structure disorganization, ruptures in plasmatic membrane, and cytoplasmic rarefaction. This work emphasizes the importance of physical parameters (polarity and doses) in cellular damage, and brings new evidence for using electrotherapy to treat C. albicans pathology process. Bioelectromagnetics. 38:95-108, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Gleyce Moreno Barbosa
- Multidisciplinary Laboratory of Pharmaceutical Sciences, Pharmacy College, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Eldio Gonçalves Dos Santos
- Multidisciplinary Laboratory of Pharmaceutical Sciences, Pharmacy College, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Francielle Neves Carvalho Capella
- Multidisciplinary Laboratory of Pharmaceutical Sciences, Pharmacy College, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fortune Homsani
- Multidisciplinary Laboratory of Pharmaceutical Sciences, Pharmacy College, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Carina de Pointis Marçal
- Peptidases Research Laboratory, Paulo de Góes Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Roberta Dos Santos Valle
- Peptidases Research Laboratory, Paulo de Góes Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Érika de Araújo Abi-Chacra
- Peptidases Research Laboratory, Paulo de Góes Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lys Adriana Braga-Silva
- Peptidases Research Laboratory, Paulo de Góes Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | - Venicio Feo da Veiga
- Microscopy Sector of Paulo de Góes Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - André Luis Souza Dos Santos
- Peptidases Research Laboratory, Paulo de Góes Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Carla Holandino
- Multidisciplinary Laboratory of Pharmaceutical Sciences, Pharmacy College, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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Inhibition of Candida albicans biofilm by pure selenium nanoparticles synthesized by pulsed laser ablation in liquids. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2016; 13:1095-1103. [PMID: 27793789 DOI: 10.1016/j.nano.2016.10.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 09/09/2016] [Accepted: 10/17/2016] [Indexed: 10/20/2022]
Abstract
Selenoproteins play an important role in the human body by accomplishing essential biological functions like oxido-reductions, antioxidant defense, thyroid hormone metabolism and immune response; therefore, the possibility to synthesize selenium nanoparticles free of any contaminants is exciting for future nano-medical applications. This paper reports the first synthesis of selenium nanoparticles by femtosecond pulsed laser ablation in de-ionized water. Those pure nanoparticles have been successfully used to inhibit the formation of Candida albicans biofilms. Advanced electron microscopy images showed that selenium nanoparticles easily adhere on the biofilm, then penetrate into the pathogen, and consequently damage the cell structure by substituting with sulfur. 50% inhibition of Candida albicans biofilm was obtained at only 25 ppm. Finally, the two physical parameters proved to affect strongly the viability of Candida albicans are the crystallinity and particle size.
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Modeling and predicting drug resistance rate and strength. Eur J Clin Microbiol Infect Dis 2016; 35:1259-67. [PMID: 27209288 DOI: 10.1007/s10096-016-2659-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 07/11/2015] [Indexed: 10/21/2022]
Abstract
Drug resistance has been worsening in human infectious diseases medicine over the past several decades. Our ability to successfully control resistance depends to a large extent on our understanding of the features characterizing the process. Part of that understanding includes the rate at which new resistance has been emerging in pathogens. Along that line, resistance data covering 90 infectious diseases, 118 pathogens, and 337 molecules, from 1921 through 2007, are modeled using various statistical tools to generate regression models for the rate of new resistance emergence and for cumulative resistance build-up in pathogens. Thereafter, the strength of the association between the number of molecules put on the market and the number of resulting cases of resistance is statistically tested. Predictive models are presented for the rate at which new resistance has been emerging in infectious diseases medicine, along with predictive models for the rate of cumulative resistance build-up in the aggregate of 118 pathogens as well as in ten individual pathogens. The models are expressed as a function of time and/or as a function of the number of molecules put on the market by the pharmaceutical industry. It is found that molecules significantly induce resistance in pathogens and that new or cumulative drug resistance across infectious diseases medicine has been arising at exponential rates.
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Zhao L, Jiang J, Zhu Z, Liao Z, Yao X, Yang Y, Cao Y, Jiang Y. Lysine enhances the effect of amphotericin B against Candida albicans in vitro. Acta Biochim Biophys Sin (Shanghai) 2016; 48:182-93. [PMID: 26711896 DOI: 10.1093/abbs/gmv125] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 10/18/2015] [Indexed: 01/11/2023] Open
Abstract
Amphotericin B (AmB) is a polyene antibiotic produced by Streptomyces nodosus and has been used for >50 years in the treatment of acute systemic fungal infections. In the present study, we demonstrated that lysine, an essential amino acid, could enhance the effect of AmB against Candida albicans in vitro, although lysine itself did not exert a fungicidal effect. In addition, the combination of AmB with lysine could provide an enhanced action against Candida parapsilosis and Cryptococcus neoformans compared with AmB alone. Lysine could also enhance the antifungal effect of caspofungin or nystatin. An enhanced effect of the combination of lysine with AmB was observed for the prevention of biofilm and hypha formation. Furthermore, our results demonstrated that lysine-mediated oxidative damage, such as the generation of endogenous reactive oxygen species, may be the mechanism underlying the enhancing effect of lysine on AmB. Our results also showed that CaMCA1 gene plays an important role in increasing the sensitivity of C. albicans cells upon AmB treatment. Using AmB together with lysine may be a promising strategy for the therapy of disseminated candidiasis.
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Affiliation(s)
- Liuya Zhao
- School of Pharmacy, Second Military Medical University, Shanghai 200433, China Pharmacy Department, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Jingchen Jiang
- School of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Zhenyu Zhu
- School of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Zebin Liao
- School of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Xiangwen Yao
- School of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Yu Yang
- School of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Yingying Cao
- School of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Yuanying Jiang
- School of Pharmacy, Second Military Medical University, Shanghai 200433, China
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Manipulation of Host Diet To Reduce Gastrointestinal Colonization by the Opportunistic Pathogen Candida albicans. mSphere 2015; 1:mSphere00020-15. [PMID: 27303684 PMCID: PMC4863630 DOI: 10.1128/msphere.00020-15] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 10/17/2015] [Indexed: 11/30/2022] Open
Abstract
Candida albicans, the most common human fungal pathogen, can cause infections with a mortality rate of ~40%. C. albicans is part of the normal gut flora, but when a patient’s immune system is compromised, it can leave the gut and cause infections. By reducing the amount of C. albicans in the gut of susceptible patients, infections (and the resulting fatalities) can be prevented. Currently, this is done using antimicrobial drugs; to “preserve” drugs for treating infections, we looked for a dietary change to reduce the amount of C. albicans in the gut. Using a mouse model, we showed that adding coconut oil to the diet could become the first drug-free way to reduce C. albicans in the gut. More broadly, this model lets us study the interactions between our diet and the microbes in our body and the reasons why some of those microbes, under certain conditions, cause disease. Candida albicans, the most common human fungal pathogen, can cause systemic infections with a mortality rate of ~40%. Infections arise from colonization of the gastrointestinal (GI) tract, where C. albicans is part of the normal microflora. Reducing colonization in at-risk patients using antifungal drugs prevents C. albicans-associated mortalities. C. albicans provides a clinically relevant system for studying the relationship between diet and the microbiota as it relates to commensalism and pathogenicity. As a first step toward a dietary intervention to reduce C. albicans GI colonization, we investigated the impact of dietary lipids on murine colonization by C. albicans. Coconut oil and its constituent fatty acids have antifungal activity in vitro; we hypothesized that dietary coconut oil would reduce GI colonization by C. albicans. Colonization was lower in mice fed a coconut oil-rich diet than in mice fed diets rich in beef tallow or soybean oil. Switching beef tallow-fed mice to a coconut oil diet reduced preexisting colonization. Coconut oil reduced colonization even when the diet also contained beef tallow. Dietary coconut oil also altered the metabolic program of colonizing C. albicans cells. Long-chain fatty acids were less abundant in the cecal contents of coconut oil-fed mice than in the cecal contents of beef tallow-fed mice; the expression of genes involved in fatty acid utilization was lower in C. albicans from coconut oil-fed mice than in C. albicans from beef tallow-fed mice. Extrapolating to humans, these findings suggest that coconut oil could become the first dietary intervention to reduce C. albicans GI colonization. IMPORTANCECandida albicans, the most common human fungal pathogen, can cause infections with a mortality rate of ~40%. C. albicans is part of the normal gut flora, but when a patient’s immune system is compromised, it can leave the gut and cause infections. By reducing the amount of C. albicans in the gut of susceptible patients, infections (and the resulting fatalities) can be prevented. Currently, this is done using antimicrobial drugs; to “preserve” drugs for treating infections, we looked for a dietary change to reduce the amount of C. albicans in the gut. Using a mouse model, we showed that adding coconut oil to the diet could become the first drug-free way to reduce C. albicans in the gut. More broadly, this model lets us study the interactions between our diet and the microbes in our body and the reasons why some of those microbes, under certain conditions, cause disease. Podcast: A podcast concerning this article is available.
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Mathematical modeling of fungal infection in immune compromised individuals: The effect of back mutation on drug treatment. J Theor Biol 2015; 385:66-76. [DOI: 10.1016/j.jtbi.2015.08.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 08/18/2015] [Accepted: 08/23/2015] [Indexed: 11/21/2022]
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Delarze E, Sanglard D. Defining the frontiers between antifungal resistance, tolerance and the concept of persistence. Drug Resist Updat 2015; 23:12-19. [PMID: 26690338 DOI: 10.1016/j.drup.2015.10.001] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
A restricted number of antifungal agents are available for the therapy of fungal diseases. With the introduction of epidemiological cut-off values for each agent in important fungal pathogens based on the distribution of minimal inhibitory concentration (MIC), the distinction between wild type and drug-resistant populations has been facilitated. Antifungal resistance has been described for all currently available antifungal agents in several pathogens and most of the associated resistance mechanisms have been deciphered at the molecular level. Clinical breakpoints for some agents have been proposed and can have predictive value for the success or failure of therapy. Tolerance to antifungals has been a much more ignored area. By definition, tolerance operates at antifungal concentrations above individual intrinsic inhibitory values. Important is that tolerance to antifungal agents favours the emergence of persister cells, which are able to survive antifungal therapy and can cause relapses. Here we will review the current knowledge on antifungal tolerance, its potential mechanisms and also evaluate the role of antifungal tolerance in the efficacy of drug treatments.
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Affiliation(s)
- Eric Delarze
- Institute of Microbiology, University Hospital Lausanne and University Hospital Center, Rue de Bugnon 48, CH-1011 Lausanne, Switzerland
| | - Dominique Sanglard
- Institute of Microbiology, University Hospital Lausanne and University Hospital Center, Rue de Bugnon 48, CH-1011 Lausanne, Switzerland.
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Bardin M, Ajouz S, Comby M, Lopez-Ferber M, Graillot B, Siegwart M, Nicot PC. Is the efficacy of biological control against plant diseases likely to be more durable than that of chemical pesticides? FRONTIERS IN PLANT SCIENCE 2015; 6:566. [PMID: 26284088 PMCID: PMC4515547 DOI: 10.3389/fpls.2015.00566] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 07/09/2015] [Indexed: 05/18/2023]
Abstract
The durability of a control method for plant protection is defined as the persistence of its efficacy in space and time. It depends on (i) the selection pressure exerted by it on populations of plant pathogens and (ii) on the capacity of these pathogens to adapt to the control method. Erosion of effectiveness of conventional plant protection methods has been widely studied in the past. For example, apparition of resistance to chemical pesticides in plant pathogens or pests has been extensively documented. The durability of biological control has often been assumed to be higher than that of chemical control. Results concerning pest management in agricultural systems have shown that this assumption may not always be justified. Resistance of various pests to one or several toxins of Bacillus thuringiensis and apparition of resistance of the codling moth Cydia pomonella to the C. pomonella granulovirus have, for example, been described. In contrast with the situation for pests, the durability of biological control of plant diseases has hardly been studied and no scientific reports proving the loss of efficiency of biological control agents against plant pathogens in practice has been published so far. Knowledge concerning the possible erosion of effectiveness of biological control is essential to ensure a durable efficacy of biological control agents on target plant pathogens. This knowledge will result in identifying risk factors that can foster the selection of strains of plant pathogens resistant to biological control agents. It will also result in identifying types of biological control agents with lower risk of efficacy loss, i.e., modes of action of biological control agents that does not favor the selection of resistant isolates in natural populations of plant pathogens. An analysis of the scientific literature was then conducted to assess the potential for plant pathogens to become resistant to biological control agents.
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Affiliation(s)
- Marc Bardin
- Plant Pathology Unit, Institut National de la Recherche Agronomique, UR407, Montfavet, France
| | - Sakhr Ajouz
- Plant Pathology Unit, Institut National de la Recherche Agronomique, UR407, Montfavet, France
| | - Morgane Comby
- Plant Pathology Unit, Institut National de la Recherche Agronomique, UR407, Montfavet, France
| | - Miguel Lopez-Ferber
- Laboratoire de Génie de l’Environnement Industriel, Ecole des Mines d’Alès, Institut Mines-Telecom, Alès, France
| | - Benoît Graillot
- Laboratoire de Génie de l’Environnement Industriel, Ecole des Mines d’Alès, Institut Mines-Telecom, Alès, France
- Natural Plant Protection,Arysta LifeScience Group, Pau, France
| | - Myriam Siegwart
- Plantes et Systèmes de Culture Horticoles Unit, Institut National de la Recherche Agronomique, UR1115, Avignon, France
| | - Philippe C. Nicot
- Plant Pathology Unit, Institut National de la Recherche Agronomique, UR407, Montfavet, France
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Sherwani MA, Tufail S, Khan AA, Owais M. Gold Nanoparticle-Photosensitizer Conjugate Based Photodynamic Inactivation of Biofilm Producing Cells: Potential for Treatment of C. albicans Infection in BALB/c Mice. PLoS One 2015; 10:e0131684. [PMID: 26148012 PMCID: PMC4493101 DOI: 10.1371/journal.pone.0131684] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 06/04/2015] [Indexed: 01/14/2023] Open
Abstract
Background Photodynamic therapy (PDT) has been found to be effective in inhibiting biofilm producing organisms. We investigated the photodynamic effect of gold nanoparticle (GNP) conjugated photosensitizers against Candida albicans biofilm. We also examined the photodynamic efficacy of photosensitizer (PS) conjugated GNPs (GNP-PS) to treat skin and oral C. albicans infection in BALB/c mice. Methods The biomimetically synthesized GNPs were conjugated to photosensitizers viz. methylene blue (MB) or toluidine blue O (TB). The conjugation of PSs with GNPs was characterized by spectroscopic and microscopic techniques. The efficacy of gold nanoparticle conjugates against C. albicans biofilm was demonstrated by XTT assay and microscopic studies. The therapeutic efficacy of the combination of the GNP conjugates against cutaneous C. albicans infection was examined in mouse model by enumerating residual fungal burden and histopathological studies. Results The GNP-PS conjugate based PDT was found to effectively kill both C. albicans planktonic cells and biofilm populating hyphal forms. The mixture of GNPs conjugated to two different PSs significantly depleted the hyphal C. albicans burden against superficial skin and oral C. albicans infection in mice. Conclusion The GNP-PS conjugate combination exhibits synergism in photodynamic inactivation of C. albicans. The GNP conjugate based PDT can be employed effectively in treatment of cutaneous C. albicans infections in model animals. The antibiofilm potential of PDT therapy can also be exploited in depletion of C. albicans on medical appliances such as implants and catheters etc.
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Affiliation(s)
- Mohd. Asif Sherwani
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India
| | - Saba Tufail
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India
| | - Aijaz Ahmed Khan
- Department of Anatomy, Jawaharlal Nehru Medical College, Faculty of Medicine, Aligarh Muslim University, Aligarh, 202002, India
- * E-mail: (MO); (AAK)
| | - Mohammad Owais
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India
- * E-mail: (MO); (AAK)
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Bajpai V, Park YH, Kang S. A diterpenoid taxodone from Metasequoia glyptostroboides with antimycotic potential against clinical isolates of Candida species. J Mycol Med 2015; 25:e31-8. [DOI: 10.1016/j.mycmed.2014.10.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 09/23/2014] [Accepted: 10/29/2014] [Indexed: 11/25/2022]
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Affiliation(s)
- Krishna Kant Sharma
- Laboratory of Enzymology and Recombinant DNA Technology, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India
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Ford CB, Funt JM, Abbey D, Issi L, Guiducci C, Martinez DA, Delorey T, Li BY, White TC, Cuomo C, Rao RP, Berman J, Thompson DA, Regev A. The evolution of drug resistance in clinical isolates of Candida albicans. eLife 2015; 4:e00662. [PMID: 25646566 PMCID: PMC4383195 DOI: 10.7554/elife.00662] [Citation(s) in RCA: 189] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 12/18/2014] [Indexed: 12/31/2022] Open
Abstract
Candida albicans is both a member of the healthy human microbiome
and a major pathogen in immunocompromised individuals. Infections are typically
treated with azole inhibitors of ergosterol biosynthesis often leading to drug
resistance. Studies in clinical isolates have implicated multiple mechanisms in
resistance, but have focused on large-scale aberrations or candidate genes, and do
not comprehensively chart the genetic basis of adaptation. Here, we leveraged
next-generation sequencing to analyze 43 isolates from 11 oral candidiasis patients.
We detected newly selected mutations, including single-nucleotide polymorphisms
(SNPs), copy-number variations and loss-of-heterozygosity (LOH) events. LOH events
were commonly associated with acquired resistance, and SNPs in 240 genes may be
related to host adaptation. Conversely, most aneuploidies were transient and did not
correlate with drug resistance. Our analysis also shows that isolates also varied in
adherence, filamentation, and virulence. Our work reveals new molecular mechanisms
underlying the evolution of drug resistance and host adaptation. DOI:http://dx.doi.org/10.7554/eLife.00662.001 Nearly all humans are infected with the fungus Candida albicans. In
most people, the infection does not produce any symptoms because their immune system
is able to counteract the fungus' attempts to spread around the body. However, if the
balance between fungal attack and body defence fails, the fungus is able to spread,
which can lead to serious disease that is fatal in 42% of cases. How does C. albicans outcompete the body's defences to cause
disease? This is a pertinent question because the most effective antifungal
medicines—including the drug fluconazole—do not kill the fungus; they
only stop it from growing. This gives the fungus time to develop resistance to the
drug by becoming able to quickly replace the fungal proteins the drug destroys, or to
efficiently remove the drug from its cells. In this study, Ford et al. studied the changes that occur in the DNA of C.
albicans over time in patients who are being treated with fluconazole.
Ford et al. took 43 samples of C. albicans from 11 patients with
weakened immune systems. The experiments show that the fungus samples collected early
on were more sensitive to the drug than the samples collected later. In most cases, the genetic data suggest that the infections begin with a single
fungal cell; the cells in the later samples are its offspring. Despite this, there is
a lot of genetic variation between samples from the same patient, which indicates
that the fungus is under pressure to become more resistant to the drug. There were
240 genes—including those that can alter the surface on the fungus cells to
make it better at evading the host immune system—in which small changes
occurred over time in three or more patients. Laboratory tests revealed that many of
these genes are likely important for the fungus to survive in an animal host in the
presence of the drug. C. albicans cells usually have two genetically distinct copies of
every gene. Ford et al. found that for some genes—including some that make
surface components or are involved in expelling drugs from cells—the loss of
genetic information from one copy, so that both copies become identical, is linked to
resistance to fluconazole. However, the gain of whole or partial
chromosomes—which contain large numbers of genes—is not linked to
resistance, but may provide additional genetic material for generating diversity in
the yeast population that may help the cells to evolve resistance in the future. These experiments have identified many new candidate genes that are important for
drug resistance and evading the host immune system, and which could be used to guide
the development of new therapeutics to treat these life-threatening infections. DOI:http://dx.doi.org/10.7554/eLife.00662.002
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Affiliation(s)
- Christopher B Ford
- Department of Biology, Broad Institute of MIT and Harvard, Cambridge, United States
| | - Jason M Funt
- Department of Biology, Broad Institute of MIT and Harvard, Cambridge, United States
| | - Darren Abbey
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, United States
| | - Luca Issi
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, United States
| | | | | | - Toni Delorey
- Broad Institute of MIT and Harvard, Cambridge, United States
| | - Bi Yu Li
- Broad Institute of MIT and Harvard, Cambridge, United States
| | - Theodore C White
- School of Biological Sciences, University of Missouri at Kansas City, Kansas City, United States
| | - Christina Cuomo
- Broad Institute of MIT and Harvard, Cambridge, United States
| | - Reeta P Rao
- Department of Biology and Biotechnology, Worcester Polytechnic Institute, Worcester, United States
| | - Judith Berman
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, United States
| | - Dawn A Thompson
- Broad Institute of MIT and Harvard, Cambridge, United States
| | - Aviv Regev
- Department of Biology, Broad Institute of MIT and Harvard, Cambridge, United States
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Brown AJP, Budge S, Kaloriti D, Tillmann A, Jacobsen MD, Yin Z, Ene IV, Bohovych I, Sandai D, Kastora S, Potrykus J, Ballou ER, Childers DS, Shahana S, Leach MD. Stress adaptation in a pathogenic fungus. ACTA ACUST UNITED AC 2014; 217:144-55. [PMID: 24353214 PMCID: PMC3867497 DOI: 10.1242/jeb.088930] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Candida albicans is a major fungal pathogen of humans. This yeast is carried by many individuals as a harmless commensal, but when immune defences are perturbed it causes mucosal infections (thrush). Additionally, when the immune system becomes severely compromised, C. albicans often causes life-threatening systemic infections. A battery of virulence factors and fitness attributes promote the pathogenicity of C. albicans. Fitness attributes include robust responses to local environmental stresses, the inactivation of which attenuates virulence. Stress signalling pathways in C. albicans include evolutionarily conserved modules. However, there has been rewiring of some stress regulatory circuitry such that the roles of a number of regulators in C. albicans have diverged relative to the benign model yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe. This reflects the specific evolution of C. albicans as an opportunistic pathogen obligately associated with warm-blooded animals, compared with other yeasts that are found across diverse environmental niches. Our understanding of C. albicans stress signalling is based primarily on the in vitro responses of glucose-grown cells to individual stresses. However, in vivo this pathogen occupies complex and dynamic host niches characterised by alternative carbon sources and simultaneous exposure to combinations of stresses (rather than individual stresses). It has become apparent that changes in carbon source strongly influence stress resistance, and that some combinatorial stresses exert non-additive effects upon C. albicans. These effects, which are relevant to fungus–host interactions during disease progression, are mediated by multiple mechanisms that include signalling and chemical crosstalk, stress pathway interference and a biological transistor.
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Affiliation(s)
- Alistair J P Brown
- School of Medical Sciences, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK
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Anderson MZ, Gerstein AC, Wigen L, Baller JA, Berman J. Silencing is noisy: population and cell level noise in telomere-adjacent genes is dependent on telomere position and sir2. PLoS Genet 2014; 10:e1004436. [PMID: 25057900 PMCID: PMC4109849 DOI: 10.1371/journal.pgen.1004436] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 04/27/2014] [Indexed: 11/18/2022] Open
Abstract
Cell-to-cell gene expression noise is thought to be an important mechanism for generating phenotypic diversity. Furthermore, telomeric regions are major sites for gene amplification, which is thought to drive genetic diversity. Here we found that individual subtelomeric TLO genes exhibit increased variation in transcript and protein levels at both the cell-to-cell level as well as at the population-level. The cell-to-cell variation, termed Telomere-Adjacent Gene Expression Noise (TAGEN) was largely intrinsic noise and was dependent upon genome position: noise was reduced when a TLO gene was expressed at an ectopic internal locus and noise was elevated when a non-telomeric gene was expressed at a telomere-adjacent locus. This position-dependent TAGEN also was dependent on Sir2p, an NAD+-dependent histone deacetylase. Finally, we found that telomere silencing and TAGEN are tightly linked and regulated in cis: selection for either silencing or activation of a TLO-adjacent URA3 gene resulted in reduced noise at the neighboring TLO but not at other TLO genes. This provides experimental support to computational predictions that the ability to shift between silent and active chromatin states has a major effect on cell-to-cell noise. Furthermore, it demonstrates that these shifts affect the degree of expression variation at each telomere individually.
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Affiliation(s)
- Matthew Z. Anderson
- Department of Genetics, Cell Biology and Development, University of Minnesota – Twin Cities, Minneapolis, Minnesota, United States of America
| | - Aleeza C. Gerstein
- Department of Genetics, Cell Biology and Development, University of Minnesota – Twin Cities, Minneapolis, Minnesota, United States of America
- Department of Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel
| | - Lauren Wigen
- Department of Genetics, Cell Biology and Development, University of Minnesota – Twin Cities, Minneapolis, Minnesota, United States of America
| | - Joshua A. Baller
- Department of Genetics, Cell Biology and Development, University of Minnesota – Twin Cities, Minneapolis, Minnesota, United States of America
| | - Judith Berman
- Department of Genetics, Cell Biology and Development, University of Minnesota – Twin Cities, Minneapolis, Minnesota, United States of America
- Department of Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Israel
- * E-mail:
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Spolti P, Del Ponte EM, Dong Y, Cummings JA, Bergstrom GC. Triazole Sensitivity in a Contemporary Population of Fusarium graminearum from New York Wheat and Competitiveness of a Tebuconazole-Resistant Isolate. PLANT DISEASE 2014; 98:607-613. [PMID: 30708550 DOI: 10.1094/pdis-10-13-1051-re] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A sample of 50 isolates, including 25 each of the 3-acetyldeoxynivalenol and the 15-acetyldeoxynivalenol trichothecene genotype, from a contemporary collection of Fusarium graminearum associated with Fusarium head blight (FHB) of wheat in New York varied in sensitivity to tebuconazole (effective concentration leading to a 50% reduction of mycelial growth [EC50] of 0.28 to 8.09 mg/liter; μ = 1.12 mg/liter) and metconazole (0.05 to 0.86 mg/liter; μ = 0.33). Mean sensitivity did not differ between the trichothecene genotype groups. Isolate Gz448NY11 from Steuben County is the first tebuconazole-resistant field isolate of F. graminearum reported in the Americas and has the lowest sensitivity to tebuconazole (EC50 = 8.09 mg/liter) documented for this species. Suppression of FHB and deoxynivalenol (DON) following application of a commercial rate of tebuconazole was significantly diminished in plants inoculated with the tebuconazole-resistant isolate compared with those inoculated with a tebuconazole-sensitive isolate well documented for its aggressiveness and toxigenicity on wheat. There was no diminution of FHB and DON suppression with either isolate following application of metconazole. Significantly more individuals of the tebuconazole-resistant isolate were recovered from spikes inoculated with an equal mixture of the two isolates and sprayed with tebuconazole. Future studies are needed on the epidemiology and monitoring of triazole-resistant isolates to understand the risk that fungicide resistance poses to disease management and food security.
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Affiliation(s)
- Pierri Spolti
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca NY 14853-5904, and Departamento de Fitossanidade, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 91540000, Brazil
| | | | - Yanhong Dong
- Department of Plant Pathology, University of Minnesota, St. Paul 55108
| | - Jaime A Cummings
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University
| | - Gary C Bergstrom
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University
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Kulikov SN, Lisovskaya SA, Zelenikhin PV, Bezrodnykh EA, Shakirova DR, Blagodatskikh IV, Tikhonov VE. Antifungal activity of oligochitosans (short chain chitosans) against some Candida species and clinical isolates of Candida albicans: molecular weight-activity relationship. Eur J Med Chem 2013; 74:169-78. [PMID: 24462847 DOI: 10.1016/j.ejmech.2013.12.017] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 12/13/2013] [Accepted: 12/18/2013] [Indexed: 10/25/2022]
Abstract
A series of oligochitosans (short chain chitosans) prepared by acidic hydrolysis of chitosan and characterized by their molecular weight, polydispersity and degree of deacetylation were used to determine their anticandidal activities. This study has demonstrated that oligochitosans show a high fungistatic activity (MIC 8-512 μg/ml) against Candida species and clinical isolates of Candida albicans, which are resistant to a series of classic antibiotics. Flow cytometry analysis showed that oligochitosan possessed a high fungicidal activity as well. For the first time it was shown that even sub-MIC oligochitosan concentration suppressed the formation of C. albicans hyphal structures, cause severe cell wall alterations, and altered internal cell structure. These results indicate that oligochitosan should be considered as a possible alternative/additive to known anti-yeast agents in pharmaceutical compositions.
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Affiliation(s)
- Sergey N Kulikov
- Kazan Scientific Research Institute of Epidemiology and Microbiology, Bolshaya Krasnaya St. 67, Kazan 420015, Russia
| | - Svetlana A Lisovskaya
- Kazan Scientific Research Institute of Epidemiology and Microbiology, Bolshaya Krasnaya St. 67, Kazan 420015, Russia
| | | | - Evgeniya A Bezrodnykh
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov St. 28, Moscow 119991, Russia
| | - Diana R Shakirova
- Kazan Federal University, Kremlyovskaya St. 18, Kazan 420008, Russia
| | - Inesa V Blagodatskikh
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov St. 28, Moscow 119991, Russia
| | - Vladimir E Tikhonov
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilov St. 28, Moscow 119991, Russia.
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Vavala E, Mignogna G, Spano F, Stringaro A, Colone M, Sanguinetti M, Maras B, Angiolella L. The cell wall protein Rhd3/Pga29 is over-expressed in Candida albicans upon micafungin treatment. J Chemother 2013; 25:332-40. [PMID: 24090751 DOI: 10.1179/1973947813y.0000000091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Candida albicans cell wall constitutes a sensitive boundary that undergoes molecular changes upon environmental injuries. Antimycotics exert an intense action on cell wall eliciting both qualitative and quantitative changes of resident proteins. The emergence of drug resistance is marked by a modulation of cell wall proteomic profile. In this study, we monitored, at the proteome level through a two-dimensional gel electrophoresis-based approach, differences of cell wall proteins in sensitive and resistant strains of C. albicans, and variations occurring upon treatment of these strains with antifungal drugs. We identified Rhd3/Pga29, a glycophosphatidylinositol (GPI)-anchored protein, as the main over-expressed protein in micafungin resistant strain with respect to the sensitive control cells. A further increase of Rhd3/Pga29 took place when these resistant strains were treated with sub-lethal dose of micafungin. These results were also confirmed in other two clinical isolates resistant to caspofungin. Results were validated by Western blot analyses and RT-PCR and immunoelectron microscopy images confirmed the increase of the Rhd3/Pga29 on the cell wall as well as in the cytosolic compartment of the micafungin-treated resistant cells. Rhd3/Pga29 over-expression upon echinocandin treatment could represent a strategy of C. albicans to counteract the toxic action of this drug. A role of this protein has also been claimed in the virulence of the fungus, suggesting an involvement of Rhd3/Pga29 in the relationship between C. albicans and the host.
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Nagoba B, Sheikh N, Jahagirdar V, Kothadia S. Antifungal Drug Resistance in Candida Species. ELECTRONIC JOURNAL OF GENERAL MEDICINE 2013. [DOI: 10.29333/ejgm/82217] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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