1
|
Qu X, Bhalla K, Horianopoulos LC, Hu G, Alcázar Magaña A, Foster LJ, Roque da Silva LB, Kretschmer M, Kronstad JW. Phosphate availability conditions caspofungin tolerance, capsule attachment and titan cell formation in Cryptococcus neoformans. FRONTIERS IN FUNGAL BIOLOGY 2024; 5:1447588. [PMID: 39206133 PMCID: PMC11349702 DOI: 10.3389/ffunb.2024.1447588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Accepted: 07/26/2024] [Indexed: 09/04/2024]
Abstract
There is an urgent need for new antifungal drugs to treat invasive fungal diseases. Unfortunately, the echinocandin drugs that are fungicidal against other important fungal pathogens are ineffective against Cryptococcus neoformans, the causative agent of life-threatening meningoencephalitis in immunocompromised people. Contributing mechanisms for echinocandin tolerance are emerging with connections to calcineurin signaling, the cell wall, and membrane composition. In this context, we discovered that a defect in phosphate uptake impairs the tolerance of C. neoformans to the echinocandin caspofungin. Our previous analysis of mutants lacking three high affinity phosphate transporters revealed reduced elaboration of the polysaccharide capsule and attenuated virulence in mice. We investigated the underlying mechanisms and found that loss of the transporters and altered phosphate availability influences the cell wall and membrane composition. These changes contribute to the shedding of capsule polysaccharide thus explaining the reduced size of capsules on mutants lacking the phosphate transporters. We also found an influence of the calcineurin pathway including calcium sensitivity and an involvement of the endoplasmic reticulum in the response to phosphate limitation. Furthermore, we identified membrane and lipid composition changes consistent with the role of phosphate in phospholipid biosynthesis and with previous studies implicating membrane integrity in caspofungin tolerance. Finally, we discovered a contribution of phosphate to titan cell formation, a cell type that displays modified cell wall and capsule composition. Overall, our analysis reinforces the importance of phosphate as a regulator of cell wall and membrane composition with implications for capsule attachment and antifungal drug susceptibility.
Collapse
Affiliation(s)
- Xianya Qu
- The Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Kabir Bhalla
- The Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Linda C. Horianopoulos
- The Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Guanggan Hu
- The Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Armando Alcázar Magaña
- Department of Biochemistry and Molecular Biology, Metabolomics Core Facility, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Leonard J. Foster
- The Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
- Department of Biochemistry and Molecular Biology, Metabolomics Core Facility, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | | | - Matthias Kretschmer
- The Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - James W. Kronstad
- The Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| |
Collapse
|
2
|
Kurnia D, Lestari S, Mayanti T, Gartika M, Nurdin D. Anti-Infection of Oral Microorganisms from Herbal Medicine of Piper crocatum Ruiz & Pav. Drug Des Devel Ther 2024; 18:2531-2553. [PMID: 38952486 PMCID: PMC11215520 DOI: 10.2147/dddt.s453375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 05/20/2024] [Indexed: 07/03/2024] Open
Abstract
The WHO Global Status Report on Oral Health 2022 reveals that oral diseases caused by infection with oral pathogenic microorganisms affect nearly 3.5 billion people worldwide. Oral health problems are caused by the presence of S. mutans, S. sanguinis, E. faecalis and C. albicans in the oral cavity. Synthetic anti-infective drugs have been widely used to treat oral infections, but have been reported to cause side effects and resistance. Various strategies have been implemented to overcome this problem. Synthetic anti-infective drugs have been widely used to treat oral infections, but they have been reported to cause side effects and resistance. Therefore, it is important to look for safe anti-infective alternatives. Ethnobotanical and ethnopharmacological studies suggest that Red Betel leaf (Piper crocatum Ruiz & Pav) could be a potential source of oral anti-infectives. This review aims to discuss the pathogenesis mechanism of several microorganisms that play an important role in causing health problems, the mechanism of action of synthetic oral anti-infective drugs in inhibiting microbial growth in the oral cavity, and the potential of red betel leaf (Piper crocatum Ruiz & Pav) as an herbal oral anti-infective drug. This study emphasises the importance of researching natural components as an alternative treatment for oral infections that is more effective and can meet global needs.
Collapse
Affiliation(s)
- Dikdik Kurnia
- Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Sumedang, Indonesia
| | - Seftiana Lestari
- Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Sumedang, Indonesia
| | - Tri Mayanti
- Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Sumedang, Indonesia
| | - Meirina Gartika
- Department of Pediatric Dentistry, Faculty of Medicine, University of Padjadjaran, Bandung, Indonesia
| | - Denny Nurdin
- Departement of Conservative Dentistry, Faculty of Dentistry, Universitas Padjadjaran, Bandung, Indonesia
| |
Collapse
|
3
|
Acosta-Zaldívar M, Qi W, Mishra A, Roy U, King WR, Patton-Vogt J, Anderson MZ, Köhler JR. Candida albicans' inorganic phosphate transport and evolutionary adaptation to phosphate scarcity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.29.577887. [PMID: 38352318 PMCID: PMC10862840 DOI: 10.1101/2024.01.29.577887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/22/2024]
Abstract
Phosphorus is essential in all cells' structural, metabolic and regulatory functions. For fungal cells that import inorganic phosphate (Pi) up a steep concentration gradient, surface Pi transporters are critical capacitators of growth. Fungi must deploy Pi transporters that enable optimal Pi uptake in pH and Pi concentration ranges prevalent in their environments. Single, triple and quadruple mutants were used to characterize the four Pi transporters we identified for the human fungal pathogen Candida albicans, which must adapt to alkaline conditions during invasion of the host bloodstream and deep organs. A high-affinity Pi transporter, Pho84, was most efficient across the widest pH range while another, Pho89, showed high-affinity characteristics only within one pH unit of neutral. Two low-affinity Pi transporters, Pho87 and Fgr2, were active only in acidic conditions. Only Pho84 among the Pi transporters was clearly required in previously identified Pi-related functions including Target of Rapamycin Complex 1 signaling and hyphal growth. We used in vitro evolution and whole genome sequencing as an unbiased forward genetic approach to probe adaptation to prolonged Pi scarcity of two quadruple mutant lineages lacking all 4 Pi transporters. Lineage-specific genomic changes corresponded to divergent success of the two lineages in fitness recovery during Pi limitation. In this process, initial, large-scale genomic alterations like aneuploidies and loss of heterozygosity were eventually lost as populations presumably gained small-scale mutations. Severity of some phenotypes linked to Pi starvation, like cell wall stress hypersensitivity, decreased in parallel to evolving populations' fitness recovery in Pi scarcity, while that of others like membrane stress responses diverged from these fitness phenotypes. C. albicans therefore has diverse options to reconfigure Pi management during prolonged scarcity. Since Pi homeostasis differs substantially between fungi and humans, adaptive processes to Pi deprivation may harbor small-molecule targets that impact fungal growth and virulence.
Collapse
Affiliation(s)
- Maikel Acosta-Zaldívar
- Division of Infectious Diseases, Boston Children’s Hospital/Harvard Medical School, Boston, MA 02115, USA
- Current affiliation: Planasa, Valladolid, Spain
| | - Wanjun Qi
- Division of Infectious Diseases, Boston Children’s Hospital/Harvard Medical School, Boston, MA 02115, USA
| | - Abhishek Mishra
- Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
| | - Udita Roy
- Division of Infectious Diseases, Boston Children’s Hospital/Harvard Medical School, Boston, MA 02115, USA
| | - William R. King
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Jana Patton-Vogt
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Matthew Z. Anderson
- Center for Genomic Science Innovation, University of Wisconsin-Madison, Madison, WI
- Department of Medical Genetics, Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI
| | - Julia R. Köhler
- Division of Infectious Diseases, Boston Children’s Hospital/Harvard Medical School, Boston, MA 02115, USA
| |
Collapse
|
4
|
Hou L, Geng Z, Yuan Z, Shi X, Wang C, Chen F, Li H, Xue F. MRSL: a causal network pruning algorithm based on GWAS summary data. Brief Bioinform 2024; 25:bbae086. [PMID: 38487847 PMCID: PMC10940843 DOI: 10.1093/bib/bbae086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 02/01/2024] [Accepted: 02/15/2024] [Indexed: 03/18/2024] Open
Abstract
Causal discovery is a powerful tool to disclose underlying structures by analyzing purely observational data. Genetic variants can provide useful complementary information for structure learning. Recently, Mendelian randomization (MR) studies have provided abundant marginal causal relationships of traits. Here, we propose a causal network pruning algorithm MRSL (MR-based structure learning algorithm) based on these marginal causal relationships. MRSL combines the graph theory with multivariable MR to learn the conditional causal structure using only genome-wide association analyses (GWAS) summary statistics. Specifically, MRSL utilizes topological sorting to improve the precision of structure learning. It proposes MR-separation instead of d-separation and three candidates of sufficient separating set for MR-separation. The results of simulations revealed that MRSL had up to 2-fold higher F1 score and 100 times faster computing time than other eight competitive methods. Furthermore, we applied MRSL to 26 biomarkers and 44 International Classification of Diseases 10 (ICD10)-defined diseases using GWAS summary data from UK Biobank. The results cover most of the expected causal links that have biological interpretations and several new links supported by clinical case reports or previous observational literatures.
Collapse
Affiliation(s)
- Lei Hou
- Beijing International Center for Mathematical Research, Peking University, Beijing, People’s Republic of China, 100871
| | - Zhi Geng
- School of Mathematics and Statistics, Beijing Technology and Business University, Beijing, People’s Republic of China, 100048
| | - Zhongshang Yuan
- Department of Epidemiology and Health Statistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China, 250000
- Institute for Medical Dataology, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China, 250000
| | - Xu Shi
- Department of Biostatistics, University of Michigan, Ann Arbor, USA
| | - Chuan Wang
- Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, People's Republic of China, 250000
| | - Feng Chen
- School of Public Health, Nanjing Medical University, Nanjing, China, 211166
| | - Hongkai Li
- Department of Epidemiology and Health Statistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China, 250000
- Institute for Medical Dataology, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China, 250000
| | - Fuzhong Xue
- Department of Epidemiology and Health Statistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China, 250000
- Institute for Medical Dataology, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China, 250000
- Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, People's Republic of China, 250000
| |
Collapse
|
5
|
King WR, Singer J, Warman M, Wilson D, Hube B, Lager I, Patton-Vogt J. The glycerophosphocholine acyltransferase Gpc1 contributes to phosphatidylcholine biosynthesis, long-term viability, and embedded hyphal growth in Candida albicans. J Biol Chem 2024; 300:105543. [PMID: 38072057 PMCID: PMC10790099 DOI: 10.1016/j.jbc.2023.105543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/21/2023] Open
Abstract
Candida albicans is a commensal fungus, opportunistic pathogen, and the most common cause of fungal infection in humans. The biosynthesis of phosphatidylcholine (PC), a major eukaryotic glycerophospholipid, occurs through two primary pathways. In Saccharomyces cerevisiae and some plants, a third PC synthesis pathway, the PC deacylation/reacylation pathway (PC-DRP), has been characterized. PC-DRP begins with the acylation of the lipid turnover product, glycerophosphocholine (GPC), by the GPC acyltransferase, Gpc1, to form Lyso-PC. Lyso-PC is then acylated by lysolipid acyltransferase, Lpt1, to produce PC. Importantly, GPC, the substrate for Gpc1, is a ubiquitous metabolite available within the host. GPC is imported by C. albicans, and deletion of the major GPC transporter, Git3, leads to decreased virulence in a murine model. Here we report that GPC can be directly acylated in C. albicans by the protein product of orf19.988, a homolog of ScGpc1. Through lipidomic studies, we show loss of Gpc1 leads to a decrease in PC levels. This decrease occurs in the absence of exogenous GPC, indicating that the impact on PC levels may be greater in the human host where GPC is available. A gpc1Δ/Δ strain exhibits several sensitivities to antifungals that target lipid metabolism. Furthermore, loss of Gpc1 results in both a hyphal growth defect in embedded conditions and a decrease in long-term cell viability. These results demonstrate for the first time the importance of Gpc1 and this alternative PC biosynthesis route (PC-DRP) to the physiology of a pathogenic fungus.
Collapse
Affiliation(s)
- William R King
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Justin Singer
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Mitchell Warman
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Duncan Wilson
- Department of Biosciences, University of Exeter, Exeter, England
| | - Bernard Hube
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Products and Infection Biology Hans Knöll Institute, Jena, Germany
| | - Ida Lager
- Department of Plant Breeding, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Jana Patton-Vogt
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA.
| |
Collapse
|
6
|
King WR, Acosta-Zaldívar M, Qi W, Cherico N, Cooke L, Köhler JR, Patton-Vogt J. Glycerophosphocholine provision rescues Candida albicans growth and signaling phenotypes associated with phosphate limitation. mSphere 2023; 8:e0023123. [PMID: 37843297 PMCID: PMC10732039 DOI: 10.1128/msphere.00231-23] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 08/30/2023] [Indexed: 10/17/2023] Open
Abstract
IMPORTANCE Candida albicans is the most commonly isolated species from patients suffering from invasive fungal disease. C. albicans is most commonly a commensal organism colonizing a variety of niches in the human host. The fungus must compete for resources with the host flora to acquire essential nutrients such as phosphate. Phosphate acquisition and homeostasis have been shown to play a key role in C. albicans virulence, with several genes involved in these processes being required for normal virulence and several being upregulated during infection. In addition to inorganic phosphate (Pi), C. albicans can utilize the lipid-derived metabolite glycerophosphocholine (GPC) as a phosphate source. As GPC is available within the human host, we examined the role of GPC in phosphate homeostasis in C. albicans. We find that GPC can substitute for Pi by many though not all criteria and is likely a relevant physiological phosphate source for C. albicans.
Collapse
Affiliation(s)
- William R. King
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Maikel Acosta-Zaldívar
- Department of Infectious Diseases, Boston Children’s Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Wanjun Qi
- Department of Infectious Diseases, Boston Children’s Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Nicholas Cherico
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Lauren Cooke
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| | - Julia R. Köhler
- Department of Infectious Diseases, Boston Children’s Hospital/Harvard Medical School, Boston, Massachusetts, USA
| | - Jana Patton-Vogt
- Department of Biological Sciences, Duquesne University, Pittsburgh, Pennsylvania, USA
| |
Collapse
|
7
|
Liang J, Tang H, Snyder LF, Youngstrom CE, He BZ. Divergence of TORC1-mediated stress response leads to novel acquired stress resistance in a pathogenic yeast. PLoS Pathog 2023; 19:e1011748. [PMID: 37871123 PMCID: PMC10621968 DOI: 10.1371/journal.ppat.1011748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 11/02/2023] [Accepted: 10/11/2023] [Indexed: 10/25/2023] Open
Abstract
Acquired stress resistance (ASR) enables organisms to prepare for environmental changes that occur after an initial stressor. However, the genetic basis for ASR and how the underlying network evolved remain poorly understood. In this study, we discovered that a short phosphate starvation induces oxidative stress response (OSR) genes in the pathogenic yeast C. glabrata and protects it against a severe H2O2 stress; the same treatment, however, provides little benefit in the low pathogenic-potential relative, S. cerevisiae. This ASR involves the same transcription factors (TFs) as the OSR, but with different combinatorial logics. We show that Target-of-Rapamycin Complex 1 (TORC1) is differentially inhibited by phosphate starvation in the two species and contributes to the ASR via its proximal effector, Sch9. Therefore, evolution of the phosphate starvation-induced ASR involves the rewiring of TORC1's response to phosphate limitation and the repurposing of TF-target gene networks for the OSR using new regulatory logics.
Collapse
Affiliation(s)
- Jinye Liang
- Department of Biology, The University of Iowa, Iowa City, Iowa, United States of America
| | - Hanxi Tang
- Department of Biology, The University of Iowa, Iowa City, Iowa, United States of America
| | - Lindsey F. Snyder
- Interdisciplinary Graduate Program in Genetics, The University of Iowa, Iowa City, Iowa, United States of America
| | | | - Bin Z. He
- Department of Biology, The University of Iowa, Iowa City, Iowa, United States of America
- Interdisciplinary Graduate Program in Genetics, The University of Iowa, Iowa City, Iowa, United States of America
| |
Collapse
|
8
|
Kahl LJ, Stremmel N, Esparza-Mora MA, Wheatley RM, MacLean RC, Ralser M. Interkingdom interactions between Pseudomonas aeruginosa and Candida albicans affect clinical outcomes and antimicrobial responses. Curr Opin Microbiol 2023; 75:102368. [PMID: 37677865 DOI: 10.1016/j.mib.2023.102368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 07/24/2023] [Accepted: 07/24/2023] [Indexed: 09/09/2023]
Abstract
Infections that involve interkingdom microbial communities, such as those between bacteria and yeast pathogens, are difficult to treat, associated with worse patient outcomes, and may be a source of antimicrobial resistance. In this review, we address co-occurrence and co-infections of Candida albicans and Pseudomonas aeruginosa, two pathogens that occupy multiple infection niches in the human body, especially in immunocompromised patients. The interaction between the pathogen species influences microbe-host interactions, the effectiveness of antimicrobials and even infection outcomes, and may thus require adapted treatment strategies. However, the molecular details of bacteria-fungal interactions both inside and outside the infection sites, are insufficiently characterised. We argue that comprehensively understanding the P. aeruginosa-C. albicans interaction network through integrated systems biology approaches will capture the highly dynamic and complex nature of these polymicrobial infections and lead to a more comprehensive understanding of clinical observations such as reshaped immune defences and low antimicrobial treatment efficacy.
Collapse
Affiliation(s)
- Lisa J Kahl
- Charité Universitätsmedizin Berlin, Department of Biochemistry, 10117 Berlin, Germany
| | - Nina Stremmel
- Charité Universitätsmedizin Berlin, Department of Biochemistry, 10117 Berlin, Germany
| | | | - Rachel M Wheatley
- University of Oxford, Department of Biology, Oxford OX1 3SZ, United Kingdom
| | - R Craig MacLean
- University of Oxford, Department of Biology, Oxford OX1 3SZ, United Kingdom
| | - Markus Ralser
- Charité Universitätsmedizin Berlin, Department of Biochemistry, 10117 Berlin, Germany; University of Oxford, The Wellcome Centre for Human Genetics, Nuffield Department of Medicine, Oxford OX3 7BN, United Kingdom; Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany.
| |
Collapse
|
9
|
Liang J, Tang H, Snyder LF, Youngstrom CE, He BZ. Divergence of TORC1-mediated Stress Response Leads to Novel Acquired Stress Resistance in a Pathogenic Yeast. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.20.545716. [PMID: 37781605 PMCID: PMC10541095 DOI: 10.1101/2023.06.20.545716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Acquired stress resistance (ASR) enables organisms to prepare for environmental changes that occur after an initial stressor. However, the genetic basis for ASR and how the underlying network evolved remain poorly understood. In this study, we discovered that a short phosphate starvation induces oxidative stress response (OSR) genes in the pathogenic yeast C. glabrata and protects it against a severe H2O2 stress; the same treatment, however, provides little benefit in the low pathogenic-potential relative, S. cerevisiae. This ASR involves the same transcription factors (TFs) as the OSR, but with different combinatorial logics. We show that Target-of-Rapamycin Complex 1 (TORC1) is differentially inhibited by phosphate starvation in the two species and contributes to the ASR via its proximal effector, Sch9. Therefore, evolution of the phosphate starvation-induced ASR involves the rewiring of TORC1's response to phosphate limitation and the repurposing of TF-target gene networks for the OSR using new regulatory logics.
Collapse
Affiliation(s)
- Jinye Liang
- Biology Department, The University of Iowa, Iowa City, IA 52242
| | - Hanxi Tang
- Biology Department, The University of Iowa, Iowa City, IA 52242
| | - Lindsey F. Snyder
- Interdisciplinary Graduate Program in Genetics, The University of Iowa, Iowa City, IA 52242
| | | | - Bin Z. He
- Biology Department, The University of Iowa, Iowa City, IA 52242
| |
Collapse
|
10
|
Druseikis M, Mottola A, Berman J. The Metabolism of Susceptibility: Clearing the FoG Between Tolerance and Resistance in Candida albicans. CURRENT CLINICAL MICROBIOLOGY REPORTS 2023; 10:36-46. [DOI: 10.1007/s40588-023-00189-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
|
11
|
Matilla MA, Genova R, Martín-Mora D, Maaβ S, Becher D, Krell T. The Cellular Abundance of Chemoreceptors, Chemosensory Signaling Proteins, Sensor Histidine Kinases, and Solute Binding Proteins of Pseudomonas aeruginosa Provides Insight into Sensory Preferences and Signaling Mechanisms. Int J Mol Sci 2023; 24:ijms24021363. [PMID: 36674894 PMCID: PMC9864684 DOI: 10.3390/ijms24021363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 12/21/2022] [Accepted: 12/24/2022] [Indexed: 01/12/2023] Open
Abstract
Chemosensory pathways and two-component systems are important bacterial signal transduction systems. In the human pathogen Pseudomonas aeruginosa, these systems control many virulence traits. Previous studies showed that inorganic phosphate (Pi) deficiency induces virulence. We report here the abundance of chemosensory and two-component signaling proteins of P. aeruginosa grown in Pi deficient and sufficient media. The cellular abundance of chemoreceptors differed greatly, since a 2400-fold difference between the most and least abundant receptors was observed. For many chemoreceptors, their amount varied with the growth condition. The amount of chemoreceptors did not correlate with the magnitude of chemotaxis to their cognate chemoeffectors. Of the four chemosensory pathways, proteins of the Che chemotaxis pathway were most abundant and showed little variation in different growth conditions. The abundance of chemoreceptors and solute binding proteins indicates a sensing preference for amino acids and polyamines. There was an excess of response regulators over sensor histidine kinases in two-component systems. In contrast, ratios of the response regulators CheY and CheB to the histidine kinase CheA of the Che pathway were all below 1, indicative of different signaling mechanisms. This study will serve as a reference for exploring sensing preferences and signaling mechanisms of other bacteria.
Collapse
Affiliation(s)
- Miguel A. Matilla
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain
| | - Roberta Genova
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain
| | - David Martín-Mora
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain
| | - Sandra Maaβ
- Department of Microbial Proteomics, Institute of Microbiology, University of Greifswald, D-17489 Greifswald, Germany
| | - Dörte Becher
- Department of Microbial Proteomics, Institute of Microbiology, University of Greifswald, D-17489 Greifswald, Germany
| | - Tino Krell
- Department of Biotechnology and Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, 18008 Granada, Spain
- Correspondence: ; Tel.: +34-958-526579
| |
Collapse
|
12
|
Virulence Induction in Pseudomonas aeruginosa under Inorganic Phosphate Limitation: a Proteomics Perspective. Microbiol Spectr 2022; 10:e0259022. [PMID: 36354317 PMCID: PMC9769906 DOI: 10.1128/spectrum.02590-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Inorganic phosphate (Pi) is a central nutrient and signal molecule for bacteria. Pi limitation was shown to increase the virulence of several phylogenetically diverse pathogenic bacteria with different lifestyles. Hypophosphatemia enhances the risk of death in patients due to general bacteremia and was observed after surgical injury in humans. Phosphate therapy, or the reduction of bacterial virulence by the administration of Pi or phosphate-containing compounds, is a promising anti-infective therapy approach that will not cause cytotoxicity or the emergence of antibiotic-resistant strains. The proof of concept of phosphate therapy has been obtained using primarily Pseudomonas aeruginosa (PA). However, a detailed understanding of Pi-induced changes at protein levels is missing. Using pyocyanin production as proxy, we show that the Pi-mediated induction of virulence is a highly cooperative process that occurs between 0.2 to 0.6 mM Pi. We present a proteomics study of PA grown in minimal medium supplemented with either 0.2 mM or 1 mM Pi and rich medium. About half of the predicted PA proteins could be quantified. Among the 1,471 dysregulated proteins comparing growth in 0.2 mM to 1 mM Pi, 1,100 were depleted under Pi-deficient conditions. Most of these proteins are involved in general and energy metabolism, different biosynthetic and catabolic routes, or transport. Pi depletion caused accumulation of proteins that belong to all major families of virulence factors, including pyocyanin synthesis, secretion systems, quorum sensing, chemosensory signaling, and the secretion of proteases, phospholipases, and phosphatases, which correlated with an increase in exoenzyme production and antibacterial activity. IMPORTANCE Antibiotics are our main weapons to fight pathogenic bacteria, but the increase in antibiotic-resistant strains and their consequences represents a major global health challenge, revealing the necessity to develop alternative antimicrobial strategies that do not involve the bacterial killing or growth inhibition. P. aeruginosa has been placed second on the global priority list to guide research on the development of new antibiotics. One of the most promising alternative strategies is the phosphate therapy for which the proof of concept has been obtained for P. aeruginosa. This article reports the detailed changes at the protein levels comparing P. aeruginosa grown under Pi-abundant and Pi-depleted conditions. These data describe in detail the molecular mechanisms underlying phosphate therapy. Apart from Pi, several other phosphate-containing compounds have been used for phosphate therapy and this study will serve as a reference for comparative studies aimed at evaluating the effect of alternative compounds.
Collapse
|
13
|
Emergence and evolution of virulence in human pathogenic fungi. Trends Microbiol 2022; 30:693-704. [DOI: 10.1016/j.tim.2021.12.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 12/21/2021] [Accepted: 12/21/2021] [Indexed: 12/23/2022]
|
14
|
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.
Collapse
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
| |
Collapse
|
15
|
Frías-De-León MG, Hernández-Castro R, Conde-Cuevas E, García-Coronel IH, Vázquez-Aceituno VA, Soriano-Ursúa MA, Farfán-García ED, Ocharán-Hernández E, Rodríguez-Cerdeira C, Arenas R, Robledo-Cayetano M, Ramírez-Lozada T, Meza-Meneses P, Pinto-Almazán R, Martínez-Herrera E. Candida glabrata Antifungal Resistance and Virulence Factors, a Perfect Pathogenic Combination. Pharmaceutics 2021; 13:pharmaceutics13101529. [PMID: 34683822 PMCID: PMC8538829 DOI: 10.3390/pharmaceutics13101529] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/03/2021] [Accepted: 09/14/2021] [Indexed: 02/07/2023] Open
Abstract
In recent years, a progressive increase in the incidence of invasive fungal infections (IFIs) caused by Candida glabrata has been observed. The objective of this literature review was to study the epidemiology, drug resistance, and virulence factors associated with the C. glabrata complex. For this purpose, a systematic review (January 2001-February 2021) was conducted on the PubMed, Scielo, and Cochrane search engines with the following terms: "C. glabrata complex (C. glabrata sensu stricto, C. nivariensis, C. bracarensis)" associated with "pathogenicity" or "epidemiology" or "antibiotics resistance" or "virulence factors" with language restrictions of English and Spanish. One hundred and ninety-nine articles were found during the search. Various mechanisms of drug resistance to azoles, polyenes, and echinocandins were found for the C. glabrata complex, depending on the geographical region. Among the mechanisms found are the overexpression of drug transporters, gene mutations that alter thermotolerance, the generation of hypervirulence due to increased adhesion factors, and modifications in vital enzymes that produce cell wall proteins that prevent the activity of drugs designed for its inhibition. In addition, it was observed that the C. glabrata complex has virulence factors such as the production of proteases, phospholipases, and hemolysins, and the formation of biofilms that allows the complex to evade the host immune response and generate fungal resistance. Because of this, the C. glabrata complex possesses a perfect pathogenetic combination for the invasion of the immunocompromised host.
Collapse
Affiliation(s)
- María Guadalupe Frías-De-León
- Unidad de Investigación, Hospital Regional de Alta Especialidad de Ixtapaluca, Ixtapaluca 56530, Mexico; (M.G.F.-D.-L.); (M.R.-C.)
| | - Rigoberto Hernández-Castro
- Departamento de Ecología de Agentes Patógenos, Hospital General “Dr. Manuel Gea González”, Ciudad de México 14080, Mexico; (R.H.-C.); (V.A.V.-A.)
| | - Esther Conde-Cuevas
- Maestría en Ciencias de la Salud, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, Ciudad de México 11340, Mexico; (E.C.-C.); (I.H.G.-C.); (P.M.-M.)
| | - Itzel H. García-Coronel
- Maestría en Ciencias de la Salud, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, Ciudad de México 11340, Mexico; (E.C.-C.); (I.H.G.-C.); (P.M.-M.)
| | - Víctor Alfonso Vázquez-Aceituno
- Departamento de Ecología de Agentes Patógenos, Hospital General “Dr. Manuel Gea González”, Ciudad de México 14080, Mexico; (R.H.-C.); (V.A.V.-A.)
| | - Marvin A. Soriano-Ursúa
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, Ciudad de México 11340, Mexico; (M.A.S.-U.); (E.D.F.-G.); (E.O.-H.)
| | - Eunice D. Farfán-García
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, Ciudad de México 11340, Mexico; (M.A.S.-U.); (E.D.F.-G.); (E.O.-H.)
| | - Esther Ocharán-Hernández
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, Ciudad de México 11340, Mexico; (M.A.S.-U.); (E.D.F.-G.); (E.O.-H.)
| | - Carmen Rodríguez-Cerdeira
- Efficiency, Quality, and Costs in Health Services Research Group (EFISALUD), Galicia Sur Health Research Institute (IIS Galicia Sur), SERGAS-UVIGO, 36213 Vigo, Spain; (C.R.-C.); (R.A.)
- Dermatology Department, Hospital Vithas Ntra. Sra. de Fátima and University of Vigo, 36206 Vigo, Spain
- Campus Universitario, University of Vigo, 36310 Vigo, Spain
| | - Roberto Arenas
- Efficiency, Quality, and Costs in Health Services Research Group (EFISALUD), Galicia Sur Health Research Institute (IIS Galicia Sur), SERGAS-UVIGO, 36213 Vigo, Spain; (C.R.-C.); (R.A.)
- Sección de Micología, Hospital General “Dr. Manuel Gea González”, Tlalpan, Ciudad de México 14080, Mexico
| | - Maura Robledo-Cayetano
- Unidad de Investigación, Hospital Regional de Alta Especialidad de Ixtapaluca, Ixtapaluca 56530, Mexico; (M.G.F.-D.-L.); (M.R.-C.)
| | - Tito Ramírez-Lozada
- Servicio de Ginecología y Obstetricia, Hospital Regional de Alta Especialidad de Ixtapaluca, Ixtapaluca 56530, Mexico;
| | - Patricia Meza-Meneses
- Maestría en Ciencias de la Salud, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, Ciudad de México 11340, Mexico; (E.C.-C.); (I.H.G.-C.); (P.M.-M.)
- Servicio de Infectología, Hospital Regional de Alta Especialidad de Ixtapaluca, Ixtapaluca 56530, Mexico
| | - Rodolfo Pinto-Almazán
- Unidad de Investigación, Hospital Regional de Alta Especialidad de Ixtapaluca, Ixtapaluca 56530, Mexico; (M.G.F.-D.-L.); (M.R.-C.)
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, Ciudad de México 11340, Mexico; (M.A.S.-U.); (E.D.F.-G.); (E.O.-H.)
- Correspondence: (R.P.-A.); (E.M.-H.); Tel.: +52-555-972-9800 (R.P.-A. or E.M.-H.)
| | - Erick Martínez-Herrera
- Unidad de Investigación, Hospital Regional de Alta Especialidad de Ixtapaluca, Ixtapaluca 56530, Mexico; (M.G.F.-D.-L.); (M.R.-C.)
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, Ciudad de México 11340, Mexico; (M.A.S.-U.); (E.D.F.-G.); (E.O.-H.)
- Efficiency, Quality, and Costs in Health Services Research Group (EFISALUD), Galicia Sur Health Research Institute (IIS Galicia Sur), SERGAS-UVIGO, 36213 Vigo, Spain; (C.R.-C.); (R.A.)
- Correspondence: (R.P.-A.); (E.M.-H.); Tel.: +52-555-972-9800 (R.P.-A. or E.M.-H.)
| |
Collapse
|
16
|
Bhalla K, Qu X, Kretschmer M, Kronstad JW. The phosphate language of fungi. Trends Microbiol 2021; 30:338-349. [PMID: 34479774 DOI: 10.1016/j.tim.2021.08.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Revised: 07/31/2021] [Accepted: 08/03/2021] [Indexed: 11/20/2022]
Abstract
Phosphate is an essential macronutrient for fungal proliferation as well as a key mediator of antagonistic, beneficial, and pathogenic interactions between fungi and other organisms. In this review, we summarize recent insights into the integration of phosphate metabolism with mechanisms of fungal adaptation that support growth and survival. In particular, we highlight aspects of phosphate sensing important for responses to stress and regulation of cell-surface changes with an impact on fungal pathogenesis, host immune responses, and disease outcomes. Additionally, new studies provide insights into the influence of phosphate availability on cooperative or antagonistic interactions between fungi and other microbes, the associations of mycorrhizal and endophytic fungi with plants, and connections with plant immunity. Overall, phosphate homeostasis is emerging as an integral part of fungal metabolism and communication to support diverse lifestyles.
Collapse
Affiliation(s)
- Kabir Bhalla
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Xianya Qu
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - Matthias Kretschmer
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada
| | - James W Kronstad
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada.
| |
Collapse
|
17
|
Wang X, Zhang Z, Wu SC. Health Benefits of Silybum marianum: Phytochemistry, Pharmacology, and Applications. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:11644-11664. [PMID: 33045827 DOI: 10.1021/acs.jafc.0c04791] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Silybum marianum (SM), a well-known plant used as both a medicine and a food, has been widely used to treat various diseases, especially hepatic diseases. The seeds and fruits of SM contain a flavonolignan complex called silymarin, the active compounds of which include silybin, isosilybin, silychristin, dihydrosilybin, silydianin, and so on. In this review, we thoroughly summarize high-quality publications related to the pharmacological effects and underlying mechanisms of SM. SM has antimicrobial, anticancer, hepatoprotective, cardiovascular-protective, neuroprotective, skin-protective, antidiabetic, and other effects. Importantly, SM also counteracts the toxicities of antibiotics, metals, and pesticides. The diverse pharmacological activities of SM provide scientific evidence supporting its use in both humans and animals. Multiple signaling pathways associated with oxidative stress and inflammation are the common molecular targets of SM. Moreover, the flavonolignans of SM are potential agonists of PPARγ and ABCA1, PTP1B inhibitors, and metal chelators. At the end of the review, the potential and perspectives of SM are discussed, and these insights are expected to facilitate the application of SM and the discovery and development of new drugs. We conclude that SM is an interesting dietary medicine for health enhancement and drug discovery and warrants further investigation.
Collapse
Affiliation(s)
- Xin Wang
- College of Veterinary Medicine, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, Shandong 266109, People's Republic of China
| | - Zhen Zhang
- College of Veterinary Medicine, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, Shandong 266109, People's Republic of China
| | - Shuai-Cheng Wu
- College of Veterinary Medicine, Qingdao Agricultural University, No. 700 Changcheng Road, Qingdao, Shandong 266109, People's Republic of China
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, No. 2 Yuanmingyuan West Road, Beijing 100193, People's Republic of China
| |
Collapse
|
18
|
A Biodegradable Antifungal-Loaded Sol-Gel Coating for the Prevention and Local Treatment of Yeast Prosthetic-Joint Infections. MATERIALS 2020; 13:ma13143144. [PMID: 32679668 PMCID: PMC7411966 DOI: 10.3390/ma13143144] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 07/10/2020] [Accepted: 07/13/2020] [Indexed: 12/31/2022]
Abstract
Fungal prosthetic-joint infections are rare but devastating complications following arthroplasty. These infections are highly recurrent and expose the patient to the development of candidemia, which has high mortality rates. Patients with this condition are often immunocompromised and present several comorbidities, and thus pose a challenge for diagnosis and treatment. The most frequently isolated organisms in these infections are Candida albicans and Candida parapsilosis, pathogens that initiate the infection by developing a biofilm on the implant surface. In this study, a novel hybrid organo-inorganic sol-gel coating was developed from a mixture of organopolysiloxanes and organophosphite, to which different concentrations of fluconazole or anidulafungin were added. Then, the capacity of these coatings to prevent biofilm formation and treat mature biofilms produced by reference and clinical strains of C. albicans and C. Parapsilosis was evaluated. Anidulafungin-loaded sol-gel coatings were more effective in preventing C. albicans biofilm formation, while fluconazole-loaded sol-gel prevented C. parapsilosis biofilm formation more effectively. Treatment with unloaded sol-gel was sufficient to reduce C. albicans biofilms, and the sol-gels loaded with fluconazole or anidulafungin slightly enhanced this effect. In contrast, unloaded coatings stimulated C. parapsilosis biofilm formation, and loading with fluconazole reduced these biofilms by up to 99%. In conclusion, these coatings represent a novel therapeutic approach with potential clinical use to prevent and treat fungal prosthetic-joint infections.
Collapse
|
19
|
Antifungal In Vitro Activity of Pilosulin- and Ponericin-Like Peptides from the Giant Ant Dinoponera quadriceps and Synergistic Effects with Antimycotic Drugs. Antibiotics (Basel) 2020; 9:antibiotics9060354. [PMID: 32585881 PMCID: PMC7344683 DOI: 10.3390/antibiotics9060354] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/17/2020] [Accepted: 06/20/2020] [Indexed: 02/06/2023] Open
Abstract
Venoms from ants comprise a rich source of bioactive peptides, including antimicrobial peptides. From the proteome and peptidome of the giant ant Dinoponera quadriceps venom, members of five known classes of antimicrobial peptides were disclosed (e.g., dermaseptin-, defensin-, ICK-, pilosulin- and ponericin-like types). Based on comparative analysis, these family members have structural determinants that indicate they could display antimicrobial activities. In previous works, pilosulin- and ponericin-like peptides were demonstrated to be active against bacteria, fungi, and parasites. Herein, the antifungal activity of ponericin- and pilosulin-like peptides were assessed, aiming at the expansion of the knowledge about AMPs in predatory ants and the development of new microbicide strategies to deal with difficult-to-treat fungal infections. Synthetic pilosulin- (Dq-2562, Dq-1503, and Dq-1319) and ponericin-like (Dq-3162) peptides were evaluated for their fungicide and fungistatic activities against different species of Candida, including a drug-resistant clinical strain. The MICs and MLCs were determined for all peptides individually and in combination with general antifungal drugs by the microdilution method. The time-kill kinetic curves were set up by means of a luminescent reagent, of which the light signal is proportional to the number of viable cells. The candicidal synergism observed by the combination of subinhibitory concentrations of peptides and general antimycotic drugs were quantified by the checkerboard test and fluorescent dye permeation assay. The influence of ergosterol on the antifungal activity was verified by supplementation of culture medium. The pilosulin- (Dq-2562 and Dq-1503) and ponericin-like (Dq-3162) were the most active peptides, displaying a broad spectrum of antifungal activity in vitro, with MICs in the range of 0.625 to 10 µM. The combination of peptides and conventional antimycotic drugs displayed a synergistic reduction in the MIC values of individual peptides and drugs, while soluble ergosterol in the culture medium increased the MICs. The fungicide and fungistatic activity of the individual peptides and peptides in combination with antimycotics were time-dependent with a rapid onset of action and long-lasting effect, which involved membrane disruption as an underlying mechanism of their action. Altogether, pilosulin- and ponericin-like peptides from the giant ant D. quadriceps venom display a broad-spectrum of candicidal activity, what allows their inclusion in the row of the antifungal peptides and gives support for further studies on the development of strategies to fight candidiasis.
Collapse
|