1
|
Sousa IS, Tavares LFS, Silva BA, Moreno DSA, Alviano CS, Santos ALS, Kneipp LF. Calcineurin activity in Fonsecaea pedrosoi: tacrolimus and cyclosporine A inhibited conidia growth, filamentation and showed synergism with itraconazole. Braz J Microbiol 2024:10.1007/s42770-024-01463-2. [PMID: 39044105 DOI: 10.1007/s42770-024-01463-2] [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: 04/30/2024] [Accepted: 07/11/2024] [Indexed: 07/25/2024] Open
Abstract
Fonsecaea pedrosoi is a melanized fungus that causes chromoblastomycosis (CBM), a tropical neglected disease responsible for chronic and disability-related subcutaneous mycosis. Given the challenging nature of CBM treatment, the study of new targets and novel bioactive drugs capable of improving patient life quality is urgent. In the present work, we detected a calcineurin activity in F. pedrosoi conidial form, employing primarily colorimetric, immunoblotting and flow cytometry assays. Our findings reveal that the calcineurin activity of F. pedrosoi was stimulated by Ca2+/calmodulin, inhibited by EGTA and specific inhibitors, such as tacrolimus (FK506) and cyclosporine A (CsA), and proved to be insensitive to okadaic acid. In addition, FK506 and CsA were able to affect the cellular viability and the fungal proliferation. This effect was corroborated by transmission electron microscopy that showed both calcineurin inhibitors promoted profound changes in the ultrastructure of conidia, causing mainly cytoplasm condensation and intense vacuolization that are clear indication of cell death. Our data indicated that FK506 exhibited the highest effectiveness, with a minimum inhibitory concentration (MIC) of 3.12 mg/L, whereas CsA required 15.6 mg/L to inhibit 100% of conidial growth. Interestingly, when both were combined with itraconazole, they demonstrated anti-F. pedrosoi activity, exhibiting a synergistic effect. Moreover, the fungal filamentation was affected after treatment with both calcineurin inhibitors. These data corroborate with other calcineurin studies in fungal cells and open up further discussions aiming to establish the role of this enzyme as a potential target for antifungal therapy against CBM infections.
Collapse
Affiliation(s)
- Ingrid S Sousa
- Laboratório de Taxonomia, Bioquímica e Bioprospecção de Fungos (LTBBF), Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, 21040-900, Brazil
| | - Lucilene F S Tavares
- Laboratório de Taxonomia, Bioquímica e Bioprospecção de Fungos (LTBBF), Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, 21040-900, Brazil
| | - Bianca A Silva
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, 21941-901, Brazil
| | - Daniela S A Moreno
- Laboratório de Estrutura de Microrganismos, IMPG, UFRJ, Rio de Janeiro, 21941-902, Brazil
| | - Celuta S Alviano
- Laboratório de Estrutura de Microrganismos, IMPG, UFRJ, Rio de Janeiro, 21941-902, Brazil
| | - André L S Santos
- Laboratório de Estudos Avançados de Microrganismos Emergentes e Resistentes (LEAMER), Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, 21941-901, Brazil
- Rede Micologia RJ, Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), Rio de Janeiro, 21941-901, Brazil
| | - Lucimar F Kneipp
- Laboratório de Taxonomia, Bioquímica e Bioprospecção de Fungos (LTBBF), Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, 21040-900, Brazil.
- Rede Micologia RJ, Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), Rio de Janeiro, 21941-901, Brazil.
| |
Collapse
|
2
|
Tanwar M, Singh A, Singh TP, Sharma S, Sharma P. Comprehensive Review on the Virulence Factors and Therapeutic Strategies with the Aid of Artificial Intelligence against Mucormycosis. ACS Infect Dis 2024; 10:1431-1457. [PMID: 38682683 DOI: 10.1021/acsinfecdis.4c00082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024]
Abstract
Mucormycosis, a rare but deadly fungal infection, was an epidemic during the COVID-19 pandemic. The rise in cases (COVID-19-associated mucormycosis, CAM) is attributed to excessive steroid and antibiotic use, poor hospital hygiene, and crowded settings. Major contributing factors include diabetes and weakened immune systems. The main manifesting forms of CAM─cutaneous, pulmonary, and the deadliest, rhinocerebral─and disseminated infections elevated mortality rates to 85%. Recent focus lies on small-molecule inhibitors due to their advantages over standard treatments like surgery and liposomal amphotericin B (which carry several long-term adverse effects), offering potential central nervous system penetration, diverse targets, and simpler dosing owing to their small size, rendering the ability to traverse the blood-brain barrier via passive diffusion facilitated by the phospholipid membrane. Adaptation and versatility in mucormycosis are facilitated by a multitude of virulence factors, enabling the pathogen to dynamically respond to various environmental stressors. A comprehensive understanding of these virulence mechanisms is imperative for devising effective therapeutic interventions against this highly opportunistic pathogen that thrives in immunocompromised individuals through its angio-invasive nature. Hence, this Review delineates the principal virulence factors of mucormycosis, the mechanisms it employs to persist in challenging host environments, and the current progress in developing small-molecule inhibitors against them.
Collapse
Affiliation(s)
- Mansi Tanwar
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi-110029, India
| | - Anamika Singh
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi-110029, India
| | - Tej Pal Singh
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi-110029, India
| | - Sujata Sharma
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi-110029, India
| | - Pradeep Sharma
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi-110029, India
| |
Collapse
|
3
|
Pavesic MW, Gale AN, Nickels TJ, Harrington AA, Bussey M, Cunningham KW. Calcineurin-dependent contributions to fitness in the opportunistic pathogen Candida glabrata. mSphere 2024; 9:e0055423. [PMID: 38171022 PMCID: PMC10826367 DOI: 10.1128/msphere.00554-23] [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] [Received: 09/22/2023] [Accepted: 11/19/2023] [Indexed: 01/05/2024] Open
Abstract
The protein phosphatase calcineurin is vital for the virulence of the opportunistic fungal pathogen Candida glabrata. The host-induced stresses that activate calcineurin signaling are unknown, as are the targets of calcineurin relevant to virulence. To potentially shed light on these processes, millions of transposon insertion mutants throughout the genome of C. glabrata were profiled en masse for fitness defects in the presence of FK506, a specific inhibitor of calcineurin. Eighty-seven specific gene deficiencies depended on calcineurin signaling for full viability in vitro both in wild-type and pdr1∆ null strains lacking pleiotropic drug resistance. Three genes involved in cell wall biosynthesis (FKS1, DCW1, FLC1) possess co-essential paralogs whose expression depended on calcineurin and Crz1 in response to micafungin, a clinical antifungal that interferes with cell wall biogenesis. Interestingly, 80% of the FK506-sensitive mutants were deficient in different aspects of vesicular trafficking, such as endocytosis, exocytosis, sorting, and biogenesis of secretory proteins in the endoplasmic reticulum (ER). In response to the experimental antifungal manogepix that blocks GPI-anchor biosynthesis in the ER, calcineurin signaling increased and strongly prevented cell death independent of Crz1, one of its major targets. Comparisons between manogepix, micafungin, and the ER-stressing tunicamycin reveal a correlation between the degree of calcineurin signaling and the degree of cell survival. These findings suggest that calcineurin plays major roles in mitigating stresses of vesicular trafficking. Such stresses may arise during host infection and in response to antifungal therapies.IMPORTANCECalcineurin plays critical roles in the virulence of most pathogenic fungi. This study sheds light on those roles in the opportunistic pathogen Candida glabrata using a genome-wide analysis in vitro. The findings could lead to antifungal developments that also avoid immunosuppression.
Collapse
Affiliation(s)
- Matthew W. Pavesic
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Andrew N. Gale
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Timothy J. Nickels
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA
| | | | - Maya Bussey
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Kyle W. Cunningham
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA
| |
Collapse
|
4
|
Cen YK, He NY, Zhou WY, Liu ZQ, Zheng YG. Development of a yeast cell based method for efficient screening of high yield tacrolimus production strain. 3 Biotech 2024; 14:26. [PMID: 38169568 PMCID: PMC10757991 DOI: 10.1007/s13205-023-03870-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/21/2023] [Indexed: 01/05/2024] Open
Abstract
Tacrolimus (FK506) is a widely used and clinically important immunosuppressant drug that can be produced by fermentation of Streptomyces tsukubaensis. The industrial strains are typically obtained through multiple rounds of mutagenesis and screening, a labor-intensive process. We have established an efficient yeast cell based screening method for the evolutionary process of high-FK506-yielding strain. The S. tsukubaensis strains of different FK506 yields were tested for zone of growth inhibition of the wild type and calcineurin mutant (cnb1∆) yeast strains. We found that different FK506 yields correspond well to altered yeast growth inhibitions. Based on the combinational inhibition effects of FK506 with different antifungals that have been frequently reported, we also tested the zone of inhibition by addition of fluconazole, amphotericin B and caspofungin to the medium. In the end, for the best screening performance, we systemically evaluated the strategy when different yeast strains and different antifungals were used according to the clarity, size, and divergence of the inhibition circles. Using different yeast strains and antifungals, we successfully broadened the screening spectrum. An efficient high-FK506-yield S. tsukubaensis screening method has been established and optimized. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-023-03870-y.
Collapse
Affiliation(s)
- Yu-Ke Cen
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 China
- Engineering Research Center of Bioconversion and Bio Purification of Ministry of Education, Zhejiang University of Technology, Hangzhou, 310014 China
| | - Nai-Ying He
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 China
- Engineering Research Center of Bioconversion and Bio Purification of Ministry of Education, Zhejiang University of Technology, Hangzhou, 310014 China
| | - Wan-Ying Zhou
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 China
- Engineering Research Center of Bioconversion and Bio Purification of Ministry of Education, Zhejiang University of Technology, Hangzhou, 310014 China
| | - Zhi-Qiang Liu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 China
- Engineering Research Center of Bioconversion and Bio Purification of Ministry of Education, Zhejiang University of Technology, Hangzhou, 310014 China
| | - Yu-Guo Zheng
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014 China
- Engineering Research Center of Bioconversion and Bio Purification of Ministry of Education, Zhejiang University of Technology, Hangzhou, 310014 China
| |
Collapse
|
5
|
Szekely J, Rakchang W, Rattanaphan P, Kositpantawong N. Fluconazole and echinocandin resistance of Candida species in invasive candidiasis at a university hospital during pre-COVID-19 and the COVID-19 outbreak. Epidemiol Infect 2023; 151:e146. [PMID: 37622338 PMCID: PMC10540169 DOI: 10.1017/s0950268823001346] [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: 04/17/2023] [Revised: 08/09/2023] [Accepted: 08/09/2023] [Indexed: 08/26/2023] Open
Abstract
Antifungal susceptibility of Candida species is decreasing. Successful treatment for antifungal-resistant candida infection is challenging and associated with significant mortality. We performed a prospective observational study to identify the species and antifungal susceptibilities of invasive isolates of Candida species over a 5-year period at a university hospital in southern Thailand. Between 2017 and 2021, the species distribution was 39.1% Candida tropicalis, 24.8% Candida albicans, 20.3% Candida parapsilosis complex, 10.5% Candida glabrata, and 5.2% miscellaneous Candida spp. Notable observations include elevated minimal inhibitory concentration (MIC) and decrease susceptibility of C. tropicalis and C. glabrata to echinocandin and all tested triazoles. A shift of MIC90 value in the COVID-19 era was seen in C. albicans and C. tropicalis with azoles and echinocandins. Azole resistance increased among C. tropicalis isolates, and echinocandin resistance also increased among C. parapsilosis and C. glabrata isolates. Novel alterations in FKS1 HS1 and HS2 were detected in both isolates of anidulafungin-resistant C. parapsilosis. As Candida species have become more resistant to azoles and less susceptible to echinocandin development, the need arose to observe the emergence of resistance to both antifungal classes in candida clinical isolates, for a more effective infection control in the hospital.
Collapse
Affiliation(s)
- Jidapa Szekely
- Faculty of Medical Technology, Prince of Songkla University, Hat Yai, Thailand
| | - Wiraphan Rakchang
- Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Paramaporn Rattanaphan
- Clinical Microbiology Unit, Department of Pathology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Thailand
| | - Narongdet Kositpantawong
- Department of Internal Medicine, Faculty of Medicine, Prince of Songkla University, Hat Yai, Thailand
| |
Collapse
|
6
|
Kiyohara M, Miyazaki T, Okamoto M, Hirayama T, Makimura K, Chibana H, Nakada N, Ito Y, Sumiyoshi M, Ashizawa N, Takeda K, Iwanaga N, Takazono T, Izumikawa K, Yanagihara K, Kohno S, Mukae H. Evaluation of a Novel FKS1 R1354H Mutation Associated with Caspofungin Resistance in Candida auris Using the CRISPR-Cas9 System. J Fungi (Basel) 2023; 9:jof9050529. [PMID: 37233240 DOI: 10.3390/jof9050529] [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: 04/11/2023] [Revised: 04/27/2023] [Accepted: 04/27/2023] [Indexed: 05/27/2023] Open
Abstract
Outbreaks of invasive infections, with high mortality rates, caused by multidrug-resistant Candida auris have been reported worldwide. Although hotspot mutations in FKS1 are an established cause of echinocandin resistance, the actual contribution of these mutations to echinocandin resistance remains unknown. Here, we sequenced the FKS1 gene of a caspofungin-resistant clinical isolate (clade I) and identified a novel resistance mutation (G4061A inducing R1354H). We applied the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 system to generate a recovered strain (H1354R) in which only this single nucleotide mutation was reverted to its wild-type sequence. We also generated mutant strains with only the R1354H mutation introduced into C. auris wild-type strains (clade I and II) and analyzed their antifungal susceptibility. Compared to their parental strains, the R1354H mutants exhibited a 4- to 16-fold increase in caspofungin minimum inhibitory concentration (MIC) while the H1354R reverted strain exhibited a 4-fold decrease in caspofungin MIC. In a mouse model of disseminated candidiasis, the in vivo therapeutic effect of caspofungin was more closely related to the FKS1 R1354H mutation and the virulence of the strain than its in vitro MIC. The CRISPR-Cas9 system could thus aid in elucidating the mechanism underlying drug resistance in C. auris.
Collapse
Affiliation(s)
- Maiko Kiyohara
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Taiga Miyazaki
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
- Division of Respirology, Rheumatology, Infectious Diseases, and Neurology, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki 889-1692, Japan
| | - Michiyo Okamoto
- Medical Mycology Research Center, Chiba University, Chiba 260-8673, Japan
| | - Tatsuro Hirayama
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
- Department of Pharmacotherapeutics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Koichi Makimura
- Teikyo University Institute of Medical Mycology, Tokyo 192-0395, Japan
| | - Hiroji Chibana
- Medical Mycology Research Center, Chiba University, Chiba 260-8673, Japan
| | - Nana Nakada
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Yuya Ito
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Makoto Sumiyoshi
- Division of Respirology, Rheumatology, Infectious Diseases, and Neurology, Department of Internal Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki 889-1692, Japan
| | - Nobuyuki Ashizawa
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Kazuaki Takeda
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Naoki Iwanaga
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Takahiro Takazono
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Koichi Izumikawa
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Katsunori Yanagihara
- Department of Laboratory Medicine, Nagasaki University Hospital, Nagasaki 852-8501, Japan
| | - Shigeru Kohno
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| | - Hiroshi Mukae
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8501, Japan
| |
Collapse
|
7
|
Wang F, Han R, Chen S. An Overlooked and Underrated Endemic Mycosis-Talaromycosis and the Pathogenic Fungus Talaromyces marneffei. Clin Microbiol Rev 2023; 36:e0005122. [PMID: 36648228 PMCID: PMC10035316 DOI: 10.1128/cmr.00051-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Talaromycosis is an invasive mycosis endemic in tropical and subtropical Asia and is caused by the pathogenic fungus Talaromyces marneffei. Approximately 17,300 cases of T. marneffei infection are diagnosed annually, and the reported mortality rate is extremely high (~1/3). Despite the devastating impact of talaromycosis on immunocompromised individuals, particularly HIV-positive persons, and the increase in reported occurrences in HIV-uninfected persons, diagnostic and therapeutic approaches for talaromycosis have received far too little attention worldwide. In 2021, scientists living in countries where talaromycosis is endemic raised a global demand for it to be recognized as a neglected tropical disease. Therefore, T. marneffei and the infectious disease induced by this fungus must be treated with concern. T. marneffei is a thermally dimorphic saprophytic fungus with a complicated mycological growth process that may produce various cell types in its life cycle, including conidia, hyphae, and yeast, all of which are associated with its pathogenicity. However, understanding of the pathogenic mechanism of T. marneffei has been limited until recently. To achieve a holistic view of T. marneffei and talaromycosis, the current knowledge about talaromycosis and research breakthroughs regarding T. marneffei growth biology are discussed in this review, along with the interaction of the fungus with environmental stimuli and the host immune response to fungal infection. Importantly, the future research directions required for understanding this serious infection and its causative pathogenic fungus are also emphasized to identify solutions that will alleviate the suffering of susceptible individuals worldwide.
Collapse
Affiliation(s)
- Fang Wang
- Intensive Care Unit, Biomedical Research Center, Shenzhen Institute of Translational Medicine, Health Science Center, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People’s Hospital, Shenzhen, China
| | - RunHua Han
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Shi Chen
- Intensive Care Unit, Biomedical Research Center, Shenzhen Institute of Translational Medicine, Health Science Center, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People’s Hospital, Shenzhen, China
- Department of Burn and Plastic Surgery, Biomedical Research Center, Shenzhen Institute of Translational Medicine, Health Science Center, The First Affiliated Hospital of Shenzhen University, Shenzhen Second People’s Hospital, Shenzhen, China
| |
Collapse
|
8
|
Wang H, Zhang Y, Wang J, Chen Y, Hou T, Zhao Y, Ma Z. The sphinganine C4-hydroxylase FgSur2 regulates sensitivity to azole antifungal agents and virulence of Fusarium graminearum. Microbiol Res 2023; 271:127347. [PMID: 36907072 DOI: 10.1016/j.micres.2023.127347] [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: 01/06/2023] [Revised: 02/19/2023] [Accepted: 02/26/2023] [Indexed: 03/09/2023]
Abstract
Lipid rafts consisting of ergosterol and sphingolipids in the lipid membrane of cells play important roles in various cellular processes. However, the functions of sphingolipids and their synthetic genes in phytopathogenic fungi have not been well understood yet. In this study, we conducted genome-wide searches and carried out systematic gene deletion analysis of the sphingolipid synthesis pathway in Fusarium graminearum, a causal agent of Fusarium head blight of wheat and other cereal crops worldwide. Mycelial growth assays showed that deletion of FgBAR1, FgLAC1, FgSUR2 or FgSCS7 resulted in markedly reduced hyphal growth. Fungicide sensitivity tests showed that the sphinganine C4-hydroxylase gene FgSUR2 deletion mutant (ΔFgSUR2) exhibited significantly increased susceptibility to azole fungicides. In addition, this mutant displayed a remarkable increase in cell membrane permeability. Importantly, ΔFgSUR2 was defective in deoxynivalenol (DON) toxisome formation, leading to dramatically decreased DON biosynthesis. Moreover, the deletion of FgSUR2 resulted in dramatically decreased virulence of the pathogen on host plants. Taken together, these results indicate that FgSUR2 plays an important role in regulating the susceptibility to azoles and virulence of F. graminearum.
Collapse
Affiliation(s)
- Haixia Wang
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yueqi Zhang
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Jingrui Wang
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yun Chen
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Tingjun Hou
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Youfu Zhao
- Irrigated Agriculture Research and Extension Center, Department of Plant Pathology, Washington State University, Prosser, WA 99350, USA
| | - Zhonghua Ma
- State Key Laboratory of Rice Biology, and Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China.
| |
Collapse
|
9
|
Chadwick BJ, Ross BE, Lin X. Molecular Dissection of Crz1 and Its Dynamic Subcellular Localization in Cryptococcus neoformans. J Fungi (Basel) 2023; 9:jof9020252. [PMID: 36836365 PMCID: PMC9963361 DOI: 10.3390/jof9020252] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 02/01/2023] [Accepted: 02/08/2023] [Indexed: 02/17/2023] Open
Abstract
Across lower eukaryotes, the transcription factor Crz1 is dephosphorylated by calcineurin, which facilitates Crz1 translocation to the nucleus to regulate gene expression. In the fungal pathogen Cryptococcus neoformans, calcineurin-Crz1 signaling maintains calcium homeostasis, thermotolerance, cell wall integrity, and morphogenesis. How Crz1 distinguishes different stressors and differentially regulates cellular responses is poorly understood. Through monitoring Crz1 subcellular localization over time, we found that Crz1 transiently localizes to granules after exposure to high temperature or calcium. These granules also host the phosphatase calcineurin and Pub1, a ribonucleoprotein stress granule marker, suggesting a role of stress granules in modulating calcineurin-Crz1 signaling. Additionally, we constructed and analyzed an array of Crz1 truncation mutants. We identified the intrinsically disordered regions in Crz1 contribute to proper stress granule localization, nuclear localization, and function. Our results provide the groundwork for further determination of the mechanisms behind the complex regulation of Crz1.
Collapse
Affiliation(s)
| | | | - Xiaorong Lin
- Department of Plant Biology, University of Georgia, Athens, GA 30602, USA
- Department of Microbiology, University of Georgia, Athens, GA 30602, USA
- Correspondence:
| |
Collapse
|
10
|
Kurakado S, Matsumoto Y, Yamada T, Shimizu K, Wakasa S, Sugita T. Tacrolimus inhibits stress responses and hyphal formation via the calcineurin signaling pathway in Trichosporon asahii. Microbiol Immunol 2023; 67:49-57. [PMID: 36398783 DOI: 10.1111/1348-0421.13039] [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: 08/05/2022] [Revised: 10/09/2022] [Accepted: 11/07/2022] [Indexed: 11/19/2022]
Abstract
The pathogenic fungus Trichosporon asahii causes fatal deep-seated mycosis in immunocompromised patients. Calcineurin, which is widely conserved in eukaryotes, regulates cell growth and various stress responses in fungi. Tacrolimus (FK506), a calcineurin inhibitor, induces sensitivity to compounds that cause stress on the cell membrane and cell wall integrity. In this study, we demonstrated that FK506 affects stress responses and hyphal formation in T. asahii. In silico structural analysis revealed that amino acid residues in the binding site of the calcineurin-FKBP12 complex that interact with FK506 are conserved in T. asahii. The growth of T. asahii was delayed by FK506 in the presence of SDS or Congo red but not in the presence of calcium chloride. FK506 also inhibited hyphal formation in T. asahii. A mutant deficient of the cnb gene, which encodes the regulatory subunit B of calcineurin, exhibited stress sensitivities on exposure to SDS and Congo red and reduced the hyphal forming ability of T. asahii. In the cnb-deficient mutant, FK506 did not increase the stress sensitivity or reduce hyphal forming ability. These results suggest that FK506 affects stress responses and hyphal formation in T. asahii via the calcineurin signaling pathway.
Collapse
Affiliation(s)
- Sanae Kurakado
- Department of Microbiology, Meiji Pharmaceutical University, Tokyo, Japan
| | - Yasuhiko Matsumoto
- Department of Microbiology, Meiji Pharmaceutical University, Tokyo, Japan
| | - Tsuyoshi Yamada
- Teikyo University Institute of Medical Mycology, Tokyo, Japan.,Asia International Institute of Infectious Disease Control, Teikyo University, Tokyo, Japan
| | - Kiminori Shimizu
- Department of Biological Science and Technology, Tokyo University of Science, Tokyo, Japan.,Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Shogo Wakasa
- Department of Microbiology, Meiji Pharmaceutical University, Tokyo, Japan
| | - Takashi Sugita
- Department of Microbiology, Meiji Pharmaceutical University, Tokyo, Japan
| |
Collapse
|
11
|
Similarities and Differences among Species Closely Related to Candida albicans: C. tropicalis, C. dubliniensis, and C. auris. Cell Microbiol 2022. [DOI: 10.1155/2022/2599136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Although Candida species are widespread commensals of the microflora of healthy individuals, they are also among the most important human fungal pathogens that under certain conditions can cause diseases (candidiases) of varying severity ranging from mild superficial infections of the mucous membranes to life-threatening systemic infections. So far, the vast majority of research aimed at understanding the molecular basis of pathogenesis has been focused on the most common species—Candida albicans. Meanwhile, other closely related species belonging to the CTG clade, namely, Candida tropicalis and Candida dubliniensis, are becoming more important in clinical practice, as well as a relatively newly identified species, Candida auris. Despite the close relationship of these microorganisms, it seems that in the course of evolution, they have developed distinct biochemical, metabolic, and physiological adaptations, which they use to fit to commensal niches and achieve full virulence. Therefore, in this review, we describe the current knowledge on C. tropicalis, C. dubliniensis, and C. auris virulence factors, the formation of a mixed species biofilm and mutual communication, the environmental stress response and related changes in fungal cell metabolism, and the effect of pathogens on host defense response and susceptibility to antifungal agents used, highlighting differences with respect to C. albicans. Special attention is paid to common diagnostic problems resulting from similarities between these species and the emergence of drug resistance mechanisms. Understanding the different strategies to achieve virulence, used by important opportunistic pathogens of the genus Candida, is essential for proper diagnosis and treatment.
Collapse
|
12
|
A critical role of calcineurin in stress responses, hyphal formation, and virulence of the pathogenic fungus Trichosporon asahii. Sci Rep 2022; 12:16126. [PMID: 36167890 PMCID: PMC9515189 DOI: 10.1038/s41598-022-20507-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 09/14/2022] [Indexed: 11/26/2022] Open
Abstract
Trichosporon asahii is a conditional pathogenic fungus that causes severe and sometimes fatal infections in immunocompromised patients. While calcineurin, an essential component of a calcium-dependent signaling pathway, is known to regulate stress resistance and virulence of some pathogenic fungi, its role in T. asahii has not been investigated. Here, we demonstrated that calcineurin gene-deficient T. asahii mutants are sensitive to high temperature as well as cell-membrane and cell-wall stress, and exhibit decreased hyphal formation and virulence against silkworms. Growth of T. asahii mutants deficient in genes encoding subunits of calcineurin, cna1 and cnb1, was delayed at 40 °C. The cna1 and cnb1 gene-deficient mutants also showed sensitivity to sodium dodecyl sulfate, Congo red, dithiothreitol, and tunicamycin. On the other hand, these mutants exhibited no sensitivity to caffeine, sorbitol, monensin, CaCl2, LiCl, NaCl, amphotericin B, fluconazole, or voriconazole. The ratio of hyphal formation in the cna1 and cnb1 gene-deficient mutants was decreased. Moreover, the virulence of the cna1 and cnb1 gene-deficient mutants against silkworms was attenuated. These phenotypes were restored by re-introducing each respective gene into the gene-deficient mutants. Our findings suggest that calcineurin has a role in regulating the cellular stress response and virulence of T. asahii.
Collapse
|
13
|
Lima R, Ribeiro FC, Colombo AL, de Almeida JN. The emerging threat antifungal-resistant Candida tropicalis in humans, animals, and environment. FRONTIERS IN FUNGAL BIOLOGY 2022; 3:957021. [PMID: 37746212 PMCID: PMC10512401 DOI: 10.3389/ffunb.2022.957021] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 07/28/2022] [Indexed: 09/26/2023]
Abstract
Antifungal resistance in humans, animals, and the environment is an emerging problem. Among the different fungal species that can develop resistance, Candida tropicalis is ubiquitous and causes infections in animals and humans. In Asia and some Latin American countries, C. tropicalis is among the most common species related to candidemia, and mortality rates are usually above 40%. Fluconazole resistance is especially reported in Asian countries and clonal spread in humans and the environment has been investigated in some studies. In Brazil, high rates of azole resistance have been found in animals and the environment. Multidrug resistance is still rare, but recent reports of clinical multidrug-resistant isolates are worrisome. The molecular apparatus of antifungal resistance has been majorly investigated in clinical C. tropicalis isolates, revealing that this species can develop resistance through the conjunction of different adaptative mechanisms. In this review article, we summarize the main findings regarding antifungal resistance and Candida tropicalis through an "One Health" approach.
Collapse
Affiliation(s)
- Ricardo Lima
- Special Mycology Laboratory, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Felipe C. Ribeiro
- Special Mycology Laboratory, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Arnaldo L. Colombo
- Special Mycology Laboratory, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Joăo N. de Almeida
- Special Mycology Laboratory, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
- Clinical Laboratory, Hospital Israelita Albert Einstein, São Paulo, Brazil
| |
Collapse
|
14
|
Yu S, Paderu P, Lee A, Eirekat S, Healey K, Chen L, Perlin DS, Zhao Y. Histone Acetylation Regulator Gcn5 Mediates Drug Resistance and Virulence of Candida glabrata. Microbiol Spectr 2022; 10:e0096322. [PMID: 35658596 PMCID: PMC9241792 DOI: 10.1128/spectrum.00963-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 05/17/2022] [Indexed: 01/08/2023] Open
Abstract
Candida glabrata is poised to adapt to drug pressure rapidly and acquire antifungal resistance leading to therapeutic failure. Given the limited antifungal armamentarium, there is an unmet need to explore new targets or therapeutic strategies for antifungal treatment. The lysine acetyltransferase Gcn5 has been implicated in the pathogenesis of C. albicans. Yet how Gcn5 functions and impacts antifungal resistance in C. glabrata is unknown. Disrupting GCN5 rendered C. glabrata cells more sensitive to various stressors, partially reverted resistance in drug-resistant mutants, and attenuated the emergence of resistance compared to wild-type cells. RNA sequencing (RNA-seq) analysis revealed transcriptomic changes involving multiple biological processes and different transcriptional responses to antifungal drugs in gcn5Δ cells compared to wild-type cells. GCN5 deletion also resulted in reduced intracellular survival within THP-1 macrophages. In summary, Gcn5 plays a critical role in modulating the virulence of C. glabrata and regulating its response to antifungal pressure and host defense. IMPORTANCE As an important and successful human pathogen, Candida glabrata is known for its swift adaptation and rapid acquisition of resistance to the most commonly used antifungal agents, resulting in therapeutic failure in clinical settings. Here, we describe that the histone acetyltransferase Gcn5 is a key factor in adapting to antifungal pressure and developing resistance in C. glabrata. The results provide new insights into epigenetic control over the drug response in C. glabrata and may be useful for drug target discovery and the development of new therapeutic strategies to combat fungal infections.
Collapse
Affiliation(s)
- Shuying Yu
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, New Jersey, USA
- Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, People’s Republic of China
- Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases (BZ0447), Beijing, People’s Republic of China
| | - Padmaja Paderu
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, New Jersey, USA
| | - Annie Lee
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, New Jersey, USA
| | - Sami Eirekat
- Department of Biology, William Paterson University, Wayne, New Jersey, USA
| | - Kelley Healey
- Department of Biology, William Paterson University, Wayne, New Jersey, USA
| | - Liang Chen
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, New Jersey, USA
- Department of Medical Sciences, Hackensack Meridian School of Medicine, Nutley, New Jersey, USA
| | - David S. Perlin
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, New Jersey, USA
- Department of Medical Sciences, Hackensack Meridian School of Medicine, Nutley, New Jersey, USA
- Department of Microbiology and Immunology, Georgetown University School of Medicine, Washington, DC, USA
| | - Yanan Zhao
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, New Jersey, USA
- Department of Medical Sciences, Hackensack Meridian School of Medicine, Nutley, New Jersey, USA
| |
Collapse
|
15
|
Bohner F, Papp C, Gácser A. The effect of antifungal resistance development on the virulence of Candida species. FEMS Yeast Res 2022; 22:6552956. [PMID: 35325128 PMCID: PMC9466593 DOI: 10.1093/femsyr/foac019] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 02/24/2022] [Accepted: 03/21/2022] [Indexed: 11/12/2022] Open
Abstract
In recent years, the relevance of diseases associated with fungal pathogens increased worldwide. Members of the Candida genus are responsible for the greatest number of fungal bloodstream infections every year. Epidemiological data consistently indicate a modest shift toward non-albicans species, albeit Candidaalbicans is still the most recognizable species within the genus. As a result, the number of clinically relevant pathogens has increased, and, despite their distinct pathogenicity features, the applicable antifungal agents remained the same. For bloodstream infections, only three classes of drugs are routinely used, namely polyenes, azoles and echinocandins. Antifungal resistance toward all three antifungal drug classes frequently occurs in clinical settings. Compared with the broad range of literature on virulence and antifungal resistance of Candida species separately, only a small portion of studies examined the effect of resistance on virulence. These studies found that resistance to polyenes and echinocandins concluded in significant decrease in the virulence in different Candida species. Meanwhile, in some cases, resistance to azole type antifungals resulted in increased virulence depending on the species and isolates. These findings underline the importance of studies aiming to dissect the connections of virulence and resistance in Candida species.
Collapse
Affiliation(s)
- Flora Bohner
- HCEMM-USZ Fungal Pathogens Research Group, Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Csaba Papp
- HCEMM-USZ Fungal Pathogens Research Group, Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Attila Gácser
- HCEMM-USZ Fungal Pathogens Research Group, Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary.,MTA-SZTE "Lendület" Mycobiome Research Group, University of Szeged, Szeged, Hungary
| |
Collapse
|
16
|
The sat1 Gene Is Required for the Growth and Virulence of the Human Pathogenic Fungus Aspergillus fumigatus. Microbiol Spectr 2022; 10:e0155821. [PMID: 35107385 PMCID: PMC8809347 DOI: 10.1128/spectrum.01558-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aspergillus fumigatus is an important opportunistic pathogenic fungus that causes invasive aspergillosis in immunocompromised humans. Regulated fungal growth is essential for disease development and progression. Thus, screening for genes that regulate fungal growth may lead to the identification of potential therapeutic targets for invasive aspergillosis (IA). Screening of the transfer DNA (T-DNA) random-insertion A. fumigatus mutants identified a severe growth deficiency mutant AFM2954 and featured sat1 as the mutated gene described as a putative intracellular protein transporter of unknown function. The deletion of sat1 exhibited severe growth defects and significantly increased the nematode and mouse survival rates and decreased the fungal loads and histopathological damages in mouse lungs. Transcriptomic analyses revealed expression changes associated with the cell wall synthesis, the tricarboxylic acid cycle (TCA cycle), and oxidative phosphorylation genes in the sat1 mutant. Deletion of the gene resulted in resistance to cell wall-perturbing agents and thickened cell wall as well as reduced ATP contents and mitochondrial membrane potential, suggested that sat1 affected the cell wall synthesis and mitochondrial function of A. fumigatus. All together, our study uncovered novel functions of sat1 in growth and virulence of A. fumigatus and provided a theoretical basis for the development of new therapeutic target for treating IA patients. IMPORTANCE Aspergillus fumigatus is the main causative agent of invasive aspergillosis in immunocompromised hosts, with up to 90% lethality. Nevertheless, the fungal factors that regulate the pathogenesis of A. fumigatus remain largely unknown. Better understanding of the mechanisms controlling growth of A. fumigatus may provide novel therapeutic targets. In the present study, we characterized sat1 in the opportunistic pathogen A. fumigatus. The function of sat1 remains unknown. We proved its important role in growth and virulence, likely because of its effects on cell wall synthesis and mitochondrial functions.
Collapse
|
17
|
Fu C, Beattie SR, Jezewski AJ, Robbins N, Whitesell L, Krysan DJ, Cowen LE. Genetic analysis of Hsp90 function in Cryptococcus neoformans highlights key roles in stress tolerance and virulence. Genetics 2022; 220:iyab164. [PMID: 34849848 PMCID: PMC8733452 DOI: 10.1093/genetics/iyab164] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 09/27/2021] [Indexed: 11/13/2022] Open
Abstract
The opportunistic human fungal pathogen Cryptococcus neoformans has tremendous impact on global health, causing 181,000 deaths annually. Current treatment options are limited, and the frequent development of drug resistance exacerbates the challenge of managing invasive cryptococcal infections. In diverse fungal pathogens, the essential molecular chaperone Hsp90 governs fungal survival, drug resistance, and virulence. Therefore, targeting this chaperone has emerged as a promising approach to combat fungal infections. However, the role of Hsp90 in supporting C. neoformans pathogenesis remains largely elusive due to a lack of genetic characterization. To help dissect the functions of Hsp90 in C. neoformans, we generated a conditional expression strain in which HSP90 is under control of the copper-repressible promoter CTR4-2. Addition of copper to culture medium depleted Hsp90 transcript and protein levels in this strain, resulting in compromised fungal growth at host temperature; increased sensitivity to stressors, including the azole class of antifungals; altered C. neoformans morphology; and impaired melanin production. Finally, leveraging the fact that copper concentrations vary widely in different mouse tissues, we demonstrated attenuated virulence for the CTR4-2p-HSP90 mutant specifically in an inhalation model of Cryptococcus infection. During invasion and establishment of infection in this mouse model, the pathogen is exposed to the relatively high copper concentrations found in the lung as compared to blood. Overall, this work generates a tractable genetic system to study the role of Hsp90 in supporting the pathogenicity of C. neoformans and provides proof-of-principle that targeting Hsp90 holds great promise as a strategy to control cryptococcal infection.
Collapse
Affiliation(s)
- Ci Fu
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Sarah R Beattie
- Departments of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Andrew J Jezewski
- Departments of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Luke Whitesell
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Damian J Krysan
- Departments of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
- Microbiology/Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1M1, Canada
| |
Collapse
|
18
|
Drug repurposing strategies in the development of potential antifungal agents. Appl Microbiol Biotechnol 2021; 105:5259-5279. [PMID: 34151414 PMCID: PMC8214983 DOI: 10.1007/s00253-021-11407-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 06/01/2021] [Accepted: 06/08/2021] [Indexed: 12/15/2022]
Abstract
Abstract The morbidity and mortality caused by invasive fungal infections are increasing across the globe due to developments in transplant surgery, the use of immunosuppressive agents, and the emergence of drug-resistant fungal strains, which has led to a challenge in terms of treatment due to the limitations of three classes of drugs. Hence, it is imperative to establish effective strategies to identify and design new antifungal drugs. Drug repurposing is a potential way of expanding the application of existing drugs. Recently, various existing drugs have been shown to be useful in the prevention and treatment of invasive fungi. In this review, we summarize the currently used antifungal agents. In addition, the most up-to-date information on the effectiveness of existing drugs with antifungal activity is discussed. Moreover, the antifungal mechanisms of existing drugs are highlighted. These data will provide valuable knowledge to stimulate further investigation and clinical application in this field. Key points • Conventional antifungal agents have limitations due to the occurrence of drug-resistant strains. • Non-antifungal drugs act as antifungal agents in various ways toward different targets. • Non-antifungal drugs with antifungal activity are demonstrated as effective antifungal strategies.
Collapse
|
19
|
Gizińska M, Staniszewska A, Kazek M, Koronkiewicz M, Kuryk Ł, Milner-Krawczyk M, Baran J, Borowiecki P, Staniszewska M. Antifungal polybrominated proxyphylline derivative induces Candida albicans calcineurin stress response in Galleria mellonella. Bioorg Med Chem Lett 2020; 30:127545. [PMID: 32931913 DOI: 10.1016/j.bmcl.2020.127545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 09/02/2020] [Accepted: 09/04/2020] [Indexed: 11/29/2022]
Abstract
Candida albicans CNB1 plays a role in the response in vitro and in vivo to stress generated by PB-WUT-01, namely 1,3-dimethyl-7-(2-((1-(3-(perbromo-2H-benzo[d][1,2,3]triazol-2-yl)propyl)-1H-1,2,3-triazol-4-yl)methoxy)propyl)-1H-purine-2,6(3H,7H)-dione. The antifungal mechanism involved the calcineurin pathway-regulated genes SAP9-10. Galleria mellonella treated with PB-WUT-01 (at 0.64 µg/mg) showed limited candidiasis and remained within the highest survival rates. The molecular mode of action of PB-WUT-01 was rationalized by in silico docking studies toward both human and C. albicans calcineurin A (CNA) and calcineurin B (CNB) complexes, respectively. PB-WUT-01 acting as a calcineurin inhibitor in the C. albicans cells enhances the cells' susceptibility. Therefore it could be a suitable alternative treatment in patients with candidiasis.
Collapse
Affiliation(s)
| | - Anna Staniszewska
- Medical University of Lublin, Racławickie 1 Street, Lublin 20-059, Poland
| | - Michalina Kazek
- The Witold Stefański Institute of Parasitology, Polish Academy of Science, Twarda 51/55, Warsaw 00-818, Poland
| | | | - Łukasz Kuryk
- National Institute of Public Health-National Institute of Hygiene, Warsaw 00-791, Poland
| | | | - Joanna Baran
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, Warsaw 00-664, Poland
| | - Paweł Borowiecki
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, Warsaw 00-664, Poland.
| | - Monika Staniszewska
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, Warsaw 00-664, Poland; Centre for Advanced Materials and Technologies, Warsaw University of Technology, Poleczki 19, Warsaw 02-822, Poland.
| |
Collapse
|
20
|
Survival Strategies of Pathogenic Candida Species in Human Blood Show Independent and Specific Adaptations. mBio 2020; 11:mBio.02435-20. [PMID: 33024045 PMCID: PMC7542370 DOI: 10.1128/mbio.02435-20] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
To ensure their survival, pathogens have to adapt immediately to new environments in their hosts, for example, during the transition from the gut to the bloodstream. Here, we investigated the basis of this adaptation in a group of fungal species which are among the most common causes of hospital-acquired infections, the Candida species. On the basis of a human whole-blood infection model, we studied which genes and processes are active over the course of an infection in both the host and four different Candida pathogens. Remarkably, we found that, while the human host response during the early phase of infection is predominantly uniform, the pathogens pursue largely individual strategies and each one regulates genes involved in largely disparate processes in the blood. Our results reveal that C. albicans, C. glabrata, C. parapsilosis, and C. tropicalis all have developed individual strategies for survival in the host. This indicates that their pathogenicity in humans has evolved several times independently and that genes which are central for survival in the host for one species may be irrelevant in another. Only four species, Candida albicans, C. glabrata, C. parapsilosis, and C. tropicalis, together account for about 90% of all Candida bloodstream infections and are among the most common causes of invasive fungal infections of humans. However, virulence potential varies among these species, and the phylogenetic tree reveals that their pathogenicity may have emerged several times independently during evolution. We therefore tested these four species in a human whole-blood infection model to determine, via comprehensive dual-species RNA-sequencing analyses, which fungal infection strategies are conserved and which are recent evolutionary developments. The ex vivo infection progressed from initial immune cell interactions to nearly complete killing of all fungal cells. During the course of infection, we characterized important parameters of pathogen-host interactions, such as fungal survival, types of interacting immune cells, and cytokine release. On the transcriptional level, we obtained a predominantly uniform and species-independent human response governed by a strong upregulation of proinflammatory processes, which was downregulated at later time points after most of the fungal cells were killed. In stark contrast, we observed that the different fungal species pursued predominantly individual strategies and showed significantly different global transcriptome patterns. Among other findings, our functional analyses revealed that the fungal species relied on different metabolic pathways and virulence factors to survive the host-imposed stress. These data show that adaptation of Candida species as a response to the host is not a phylogenetic trait, but rather has likely evolved independently as a prerequisite to cause human infections.
Collapse
|
21
|
Vaccination with Secreted Aspartyl Proteinase 2 Protein from Candida parapsilosis Can Enhance Survival of Mice during C. tropicalis-Mediated Systemic Candidiasis. Infect Immun 2020; 88:IAI.00312-20. [PMID: 32661125 DOI: 10.1128/iai.00312-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 07/09/2020] [Indexed: 12/21/2022] Open
Abstract
The rising incidence of non-albicans Candida species globally, along with the emergence of drug resistance, is a cause for concern. This study investigated the protective efficacy of secreted aspartyl proteinase 2 (Sap2) in systemic C. tropicalis infection. Vaccination with recombinant Sap2 (rSap2) protein from C. parapsilosis enhanced survival of mice compared to rSap2 vaccinations from C. albicans (P = 0.02), C. tropicalis (P = 0.06), and sham immunization (P = 0.04). Compared to sham-immunized mice, the fungal CFU number was significantly reduced in organs of Sap2-parapsilosis-immunized mice. Histopathologically, increased neutrophilic recruitment was observed in Sap2-parapsilosis- and Sap2-tropicalis-immunized mice. Among different rSap2 proteins, Sap2-parapsilosis vaccination induced increased titers of Sap2-specific Ig, IgG, and IgM antibodies, which could bind whole fungus. Between different groups, sera from Sap2-parapsilosis-vaccinated mice exhibited increased C. tropicalis biofilm inhibition ability in vitro and enhanced neutrophil-mediated fungal killing. Passive transfer of anti-Sap2-parapsilosis immune serum in naive mice significantly reduced fungal burdens compared to those in mice receiving anti-sham immune serum. Higher numbers of plasma cells and Candida-binding B cells in Sap2-vaccinated mice suggest a role of B cells during early stages of Sap2-mediated immune response. Additionally, increased levels of Th1/Th2/Th17 cytokines observed in Sap2-parapsilosis-vaccinated mice indicate immunomodulatory properties of Sap2. Epitope analysis performed using identified B-cell epitopes provides a basis to understand differences in immunogenicity observed among Sap2-antigens and can aid the development of a multivalent or multiepitope anti-Candida vaccine(s). In summary, our results suggest that Sap2-parapsilosis vaccination can improve mouse survival during C. tropicalis infection by inducing both humoral and cellular immunity, and higher titers of Sap2-induced antibodies are beneficial during systemic candidiasis.
Collapse
|
22
|
Song J, Liu X, Li R. Sphingolipids: Regulators of azole drug resistance and fungal pathogenicity. Mol Microbiol 2020; 114:891-905. [PMID: 32767804 DOI: 10.1111/mmi.14586] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 07/29/2020] [Accepted: 08/02/2020] [Indexed: 12/14/2022]
Abstract
In recent years, the role of sphingolipids in pathogenic fungi, in terms of pathogenicity and resistance to azole drugs, has been a rapidly growing field. This review describes evidence about the roles of sphingolipids in azole resistance and fungal virulence. Sphingolipids can serve as signaling molecules that contribute to azole resistance through modulation of the expression of drug efflux pumps. They also contribute to azole resistance by participating in various microbial pathways such as the unfolded protein response (UPR), pH-responsive Rim pathway, and pleiotropic drug resistance (PDR) pathway. In addition, sphingolipid signaling and eisosomes also coordinately regulate sphingolipid biosynthesis in response to azole-induced membrane stress. Sphingolipids are important for fungal virulence, playing roles during growth in hosts under stressful conditions, maintenance of cell wall integrity, biofilm formation, and production of various virulence factors. Finally, we discuss the possibility of exploiting fungal sphingolipids for the development of new therapeutic strategies to treat infections caused by pathogenic fungi.
Collapse
Affiliation(s)
- Jinxing Song
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province and School of Life Science, Jiangsu Normal University, Xuzhou, PR China
| | - Xiao Liu
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province and School of Life Science, Jiangsu Normal University, Xuzhou, PR China
| | - Rongpeng Li
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province and School of Life Science, Jiangsu Normal University, Xuzhou, PR China
| |
Collapse
|
23
|
Moralez AP, Perini HF, Paulo EA, Furlaneto-Maia L, Furlaneto MC. Effect of phenotypic switching on biofilm traits in Candida tropicalis. Microb Pathog 2020; 149:104346. [PMID: 32562809 DOI: 10.1016/j.micpath.2020.104346] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 06/02/2020] [Accepted: 06/11/2020] [Indexed: 10/24/2022]
Abstract
Candida tropicalis can undergo multiple forms of phenotypic switching. We have reported a switching system in C. tropicalis that is associated with changes in virulence attributes. We aimed to assess biofilm formation by distinct switch states of C. tropicalis and evaluate whether their sessile cells exhibit altered virulence traits. C. tropicalis strains included the parental phenotype (a clinical isolate) and four switch phenotypes (crepe, rough, revertant of crepe and revertant of rough). Biofilm formation and adhesion capability of sessile cells on polystyrene were assessed through quantification of total biomass. Filamentous forms were characterized by direct counting of sessile cells. A virulence assay was conducted using the Galleria mellonella infection model. Switch variants (crepe and rough) and their revertant counterparts produced higher biofilm biomass (P < 0.05) than the parental strain. Additionally, filamentous forms were enriched among sessile cells of switched strains compared to those observed for sessile cells of the parental strain, with the exception of the revertant of rough. Sessile cells of switched strains showed higher adhesion to polystyrene compared to the parental strain. Sessile cells of the crepe variant and its revertant strain (RC) exhibited higher virulence against G. mellonella larvae than sessile cells of the parental strain. Our findings indicate that switching events in C. tropicalis affect biofilm development and that sessile cells of distinct switch states may exhibit increased adhesion ability and enhanced virulence towards G. mellonella larvae.
Collapse
Affiliation(s)
- AlaneT P Moralez
- Department of Microbiology, Paraná State University of Londrina, Paraná, Brazil
| | - Hugo F Perini
- Department of Microbiology, Paraná State University of Londrina, Paraná, Brazil
| | - Eloiza A Paulo
- Department of Microbiology, Paraná State University of Londrina, Paraná, Brazil
| | - Luciana Furlaneto-Maia
- Department of Food Technology, Technological Federal University of Paraná, Londrina, Paraná, Brazil
| | - Marcia C Furlaneto
- Department of Microbiology, Paraná State University of Londrina, Paraná, Brazil.
| |
Collapse
|
24
|
Ito Y, Miyazaki T, Tanaka Y, Suematsu T, Nakayama H, Morita A, Hirayama T, Tashiro M, Takazono T, Saijo T, Shimamura S, Yamamoto K, Imamura Y, Izumikawa K, Yanagihara K, Kohno S, Mukae H. Roles of Elm1 in antifungal susceptibility and virulence in Candida glabrata. Sci Rep 2020; 10:9789. [PMID: 32555245 PMCID: PMC7299981 DOI: 10.1038/s41598-020-66620-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 05/21/2020] [Indexed: 11/09/2022] Open
Abstract
Elm1 is a serine/threonine kinase involved in multiple cellular functions, including cytokinesis, morphogenesis, and drug resistance in Saccharomyces cerevisiae; however, its roles in pathogenic fungi have not been reported. In this study, we created ELM1-deletion, ELM1-reconstituted, ELM1-overexpression, and ELM1-kinase-dead strains in the clinically important fungal pathogen Candida glabrata and investigated the roles of Elm1 in cell morphology, stress response, and virulence. The elm1Δ strain showed elongated morphology and a thicker cell wall, with analyses of cell-wall components revealing that this strain exhibited significantly increased chitin content relative to that in the wild-type and ELM1-overexpression strains. Although the elm1Δ strain exhibited slower growth than the other two strains, as well as increased sensitivity to high temperature and cell-wall-damaging agents, it showed increased virulence in a Galleria mellonella-infection model. Moreover, loss of Elm1 resulted in increased adhesion to agar plates and epithelial cells, which represent important virulence factors in C. glabrata. Furthermore, RNA sequencing revealed that expression levels of 30 adhesion-like genes were elevated in the elm1Δ strain. Importantly, all these functions were mediated by the kinase activity of Elm1. To our knowledge, this is the first report describing the functional characterization of Elm1 in pathogenic fungi.
Collapse
Affiliation(s)
- Yuya Ito
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Taiga Miyazaki
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan.
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
| | - Yutaka Tanaka
- Department of Infection and Host Defense, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Takashi Suematsu
- Central Electron Microscope Laboratory, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Hironobu Nakayama
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, Suzuka, Japan
| | - Akihiro Morita
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, Suzuka, Japan
| | - Tatsuro Hirayama
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Masato Tashiro
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Takahiro Takazono
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Tomomi Saijo
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Shintaro Shimamura
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Kazuko Yamamoto
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Yoshifumi Imamura
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Koichi Izumikawa
- Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Katsunori Yanagihara
- Department of Laboratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Shigeru Kohno
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Hiroshi Mukae
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
- Department of Respiratory Medicine, Nagasaki University Hospital, Nagasaki, Japan
| |
Collapse
|
25
|
Liu L, Yu B, Sun W, Liang C, Ying H, Zhou S, Niu H, Wang Y, Liu D, Chen Y. Calcineurin signaling pathway influences Aspergillus niger biofilm formation by affecting hydrophobicity and cell wall integrity. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:54. [PMID: 32190119 PMCID: PMC7075038 DOI: 10.1186/s13068-020-01692-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 03/02/2020] [Indexed: 05/14/2023]
Abstract
BACKGROUND Biofilms, as a kind of fixed-cell community, can greatly improve industrial fermentation efficiency in immobilized fermentation, but the regulation process is still unclear, which restricts their application. Ca2+ was reported to be a key factor affecting biofilm formation. However, the effect of Ca2+ on biofilm structure and microbiology was yet only studied in bacteria. How Ca2+-mediated calcineurin signaling pathway (CSP) alters biofilm formation in bacteria and fungi has rarely been reported. On this basis, we investigated the regulation of CSP on the formation of biofilm in Aspergillus niger. RESULTS Deletion of the key genes MidA, CchA, CrzA or CnaA in the CSP lowered the Ca2+ concentration in the mycelium to a different extent, inhibited the formation of A. niger biofilm, reduced the hydrophobicity and adhesion of spores, destroyed the cell wall integrity of hyphae, and reduced the flocculation ability of hyphae. qRT-PCR results showed that the expression of spore hydrophobic protein RodA, galactosaminogalactan (GAG) biosynthesis genes (uge3, uge5, agd3, gtb3), and α-1,3-glucan biosynthesis genes (ags1, ags3) in the ∆MidA, ∆CchA, ∆CrzA, ∆CnaA strains were significantly down-regulated compared with those of the wild type (WT). In addition, the transcription levels of the chitin synthesis gene (chsB, chsD) and β-1,3-glucan synthesis gene (FksA) were consistent with the change in chitin and β-1,3-glucan contents in mutant strains. CONCLUSION These results indicated that CSP affected the hydrophobicity and adhesion of spores, the integrity of mycelial cell walls and flocculation by affecting Ca2+ levels in mycelium, which in turn affected biofilm formation. This work provides a possible explanation for how CSP changes the formation of A. niger biofilm, and reveals a pathway for controlling biofilm formation in industrial immobilized fermentation.
Collapse
Affiliation(s)
- Li Liu
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Bin Yu
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Wenjun Sun
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Caice Liang
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Hanjie Ying
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816 People’s Republic of China
- School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou, 450001 China
| | - Shengmin Zhou
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, 200237 China
| | - Huanqing Niu
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| | - Yibing Wang
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, 200237 China
| | - Dong Liu
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816 People’s Republic of China
- School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou, 450001 China
| | - Yong Chen
- National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816 People’s Republic of China
| |
Collapse
|
26
|
Alder-Rangel A, Idnurm A, Brand AC, Brown AJP, Gorbushina A, Kelliher CM, Campos CB, Levin DE, Bell-Pedersen D, Dadachova E, Bauer FF, Gadd GM, Braus GH, Braga GUL, Brancini GTP, Walker GM, Druzhinina I, Pócsi I, Dijksterhuis J, Aguirre J, Hallsworth JE, Schumacher J, Wong KH, Selbmann L, Corrochano LM, Kupiec M, Momany M, Molin M, Requena N, Yarden O, Cordero RJB, Fischer R, Pascon RC, Mancinelli RL, Emri T, Basso TO, Rangel DEN. The Third International Symposium on Fungal Stress - ISFUS. Fungal Biol 2020; 124:235-252. [PMID: 32389286 DOI: 10.1016/j.funbio.2020.02.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Accepted: 02/11/2020] [Indexed: 12/19/2022]
Abstract
Stress is a normal part of life for fungi, which can survive in environments considered inhospitable or hostile for other organisms. Due to the ability of fungi to respond to, survive in, and transform the environment, even under severe stresses, many researchers are exploring the mechanisms that enable fungi to adapt to stress. The International Symposium on Fungal Stress (ISFUS) brings together leading scientists from around the world who research fungal stress. This article discusses presentations given at the third ISFUS, held in São José dos Campos, São Paulo, Brazil in 2019, thereby summarizing the state-of-the-art knowledge on fungal stress, a field that includes microbiology, agriculture, ecology, biotechnology, medicine, and astrobiology.
Collapse
Affiliation(s)
| | - Alexander Idnurm
- School of BioSciences, The University of Melbourne, VIC, Australia
| | - Alexandra C Brand
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, England, UK
| | - Alistair J P Brown
- Medical Research Council Centre for Medical Mycology at the University of Exeter, Exeter, England, UK
| | - Anna Gorbushina
- Bundesanstalt für Materialforschung und -prüfung, Materials and the Environment, Berlin, Germany
| | - Christina M Kelliher
- Department of Molecular & Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Claudia B Campos
- Departamento de Ciência e Tecnologia, Universidade Federal de São Paulo, São José dos Campos, SP, Brazil
| | - David E Levin
- Boston University Goldman School of Dental Medicine, Boston, MA, USA
| | - Deborah Bell-Pedersen
- Center for Biological Clocks Research, Department of Biology, Texas A&M University, College Station, TX, USA
| | - Ekaterina Dadachova
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK, Canada
| | - Florian F Bauer
- Institute for Wine Biotechnology, Department of Viticulture and Oenology, Stellenbosch University, Matieland, South Africa
| | - Geoffrey M Gadd
- Geomicrobiology Group, School of Life Sciences, University of Dundee, Dundee, Scotland, UK
| | - Gerhard H Braus
- Department of Molecular Microbiology and Genetics, Institute of Microbiology and Genetics and Goettingen Center for Molecular Biosciences, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Gilberto U L Braga
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Guilherme T P Brancini
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Graeme M Walker
- School of Applied Sciences, Abertay University, Dundee, Scotland, UK
| | | | - István Pócsi
- Department of Molecular Biotechnology and Microbiology, University of Debrecen, Debrecen, Hungary
| | - Jan Dijksterhuis
- Westerdijk Fungal Biodiversity Institute, Utrecht, the Netherlands
| | - Jesús Aguirre
- Departamento de Biología Celular y del Desarrollo, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - John E Hallsworth
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, Northern Ireland, UK
| | - Julia Schumacher
- Bundesanstalt für Materialforschung und -prüfung, Materials and the Environment, Berlin, Germany
| | - Koon Ho Wong
- Faculty of Health Sciences, University of Macau, Avenida da Universidade, Taipa, Macau SAR, China
| | - Laura Selbmann
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy; Italian National Antarctic Museum (MNA), Mycological Section, Genoa, Italy
| | | | - Martin Kupiec
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
| | - Michelle Momany
- Fungal Biology Group & Plant Biology Department, University of Georgia, Athens, GA, USA
| | - Mikael Molin
- Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Natalia Requena
- Molecular Phytopathology Department, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Oded Yarden
- Department of Plant Pathology and Microbiology, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jeruslaem, Rehovot 7610001, Israel
| | - Radamés J B Cordero
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 21205, USA
| | - Reinhard Fischer
- Department of Microbiology, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Renata C Pascon
- Biological Sciences Department, Universidade Federal de São Paulo, Diadema, SP, Brazil
| | | | - Tamas Emri
- Department of Molecular Biotechnology and Microbiology, University of Debrecen, Debrecen, Hungary
| | - Thiago O Basso
- Department of Chemical Engineering, Escola Politécnica, Universidade de São Paulo, São Paulo, SP, Brazil
| | | |
Collapse
|
27
|
Zheng YQ, Pan KS, Latgé JP, Andrianopoulos A, Luo H, Yan RF, Wei JY, Huang CY, Cao CW. Calcineurin A Is Essential in the Regulation of Asexual Development, Stress Responses and Pathogenesis in Talaromyces marneffei. Front Microbiol 2020; 10:3094. [PMID: 32038542 PMCID: PMC6985273 DOI: 10.3389/fmicb.2019.03094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Accepted: 12/20/2019] [Indexed: 11/27/2022] Open
Abstract
Talaromyces marneffei is a common cause of infection in immunocompromised patients in Southeast Asia and Southern China. The pathogenicity of T. marneffei depends on the ability of the fungus to survive the cytotoxic processes of the host immune system and grow inside host macrophages. These mechanisms that allow T. marneffei to survive macrophage-induced death are poorly understood. In this study, we examined the role of a calcineurin homolog (cnaA) from T. marneffei during growth, morphogenesis and infection. Deletion of the cnaA gene in T. marneffei resulted in a strain with significant defects in conidiation, germination, morphogenesis, cell wall integrity, and resistance to various stressors. The ΔcnaA mutant showed a lower minimal inhibitory concentration (MIC) against caspofungin (16 μg/ml to 2 μg/ml) and micafungin (from 32 μg/ml to 4 μg/ml) compared with the wild-type. These results suggest that targeting calcineurin in combination with echinocandin treatment may be effective for life-threatening systemic T. marneffei infection. Importantly, the cnaA mutant was incapable of adapting to the macrophage environment in vitro and displayed virulence defects in a mouse model of invasive talaromycosis. For the first time, a role has been shown for cnaA in the morphology and pathogenicity of a dimorphic pathogenic filamentous fungus.
Collapse
Affiliation(s)
- Yan-Qing Zheng
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Kai-Su Pan
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | | | - Alex Andrianopoulos
- School of Biosciences, The University of Melbourne, Parkville, VIC, Australia
| | - Hong Luo
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Ru-Fan Yan
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Jin-Ying Wei
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Chun-Yang Huang
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Cun-Wei Cao
- Department of Dermatology and Venereology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
| |
Collapse
|
28
|
Park HS, Lee SC, Cardenas ME, Heitman J. Calcium-Calmodulin-Calcineurin Signaling: A Globally Conserved Virulence Cascade in Eukaryotic Microbial Pathogens. Cell Host Microbe 2020; 26:453-462. [PMID: 31600499 DOI: 10.1016/j.chom.2019.08.004] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/29/2019] [Accepted: 08/02/2019] [Indexed: 12/19/2022]
Abstract
Calcium is an abundant intracellular ion, and calcium homeostasis plays crucial roles in several cellular processes. The calcineurin signaling cascade is one of the major pathways governed by intracellular calcium. Calcineurin, a conserved protein from yeast to humans, is a calcium-calmodulin-dependent serine-threonine-specific phosphatase that orchestrates cellular stress responses. In eukaryotic microbial pathogens, calcineurin controls essential virulence pathways, such as the ability to grow at host temperature, morphogenesis to enable invasive hyphal growth, drug tolerance and resistance, cell wall integrity, and sexual development. Therefore, the calcineurin cascade is an attractive target in drug development against eukaryotic pathogens. In the present review, we summarize and discuss the current knowledge on the roles of calcineurin in eukaryotic microbial pathogens, focusing on fungi and parasitic protists.
Collapse
Affiliation(s)
- Hee-Soo Park
- School of Food Science and Biotechnology, Institute of Agricultural Science and Technology, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Soo Chan Lee
- South Texas Center for Emerging Infectious Diseases (STCEID), Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Maria E Cardenas
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
| |
Collapse
|
29
|
Yang F, Teoh F, Tan ASM, Cao Y, Pavelka N, Berman J. Aneuploidy Enables Cross-Adaptation to Unrelated Drugs. Mol Biol Evol 2020; 36:1768-1782. [PMID: 31028698 PMCID: PMC6657732 DOI: 10.1093/molbev/msz104] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Aneuploidy is common both in tumor cells responding to chemotherapeutic agents and in fungal cells adapting to antifungal drugs. Because aneuploidy simultaneously affects many genes, it has the potential to confer multiple phenotypes to the same cells. Here, we analyzed the mechanisms by which Candida albicans, the most prevalent human fungal pathogen, acquires the ability to survive both chemotherapeutic agents and antifungal drugs. Strikingly, adaptation to both types of drugs was accompanied by the acquisition of specific whole-chromosome aneuploidies, with some aneuploid karyotypes recovered independently and repeatedly from very different drug conditions. Specifically, strains selected for survival in hydroxyurea, an anticancer drug, acquired cross-adaptation to caspofungin, a first-line antifungal drug, and both acquired traits were attributable to trisomy of the same chromosome: loss of trisomy was accompanied by loss of adaptation to both drugs. Mechanistically, aneuploidy simultaneously altered the copy number of most genes on chromosome 2, yet survival in hydroxyurea or caspofungin required different genes and stress response pathways. Similarly, chromosome 5 monosomy conferred increased tolerance to both fluconazole and to caspofungin, antifungals with different mechanisms of action. Thus, the potential for cross-adaptation is not a feature of aneuploidy per se; rather, it is dependent on specific genes harbored on given aneuploid chromosomes. Furthermore, pre-exposure to hydroxyurea increased the frequency of appearance of caspofungin survivors, and hydroxyurea-adapted C. albicans cells were refractory to antifungal drug treatment in a mouse model of systemic candidiasis. This highlights the potential clinical consequences for the management of cancer chemotherapy patients at risk of fungal infections.
Collapse
Affiliation(s)
- Feng Yang
- Department of Molecular Microbiology and Biotechnology, School of Molecular Cell Biology and Biotechnology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Flora Teoh
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR), Singapore
| | - Alrina Shin Min Tan
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR), Singapore
| | - Yongbing Cao
- Department of Vascular Disease, Shanghai TCM-Integrated Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China.,Shanghai TCM-Integrated Institute of Vascular Disease, Shanghai, China
| | - Norman Pavelka
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR), Singapore
| | - Judith Berman
- Department of Molecular Microbiology and Biotechnology, School of Molecular Cell Biology and Biotechnology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| |
Collapse
|
30
|
A Mechanosensitive Channel Governs Lipid Flippase-Mediated Echinocandin Resistance in Cryptococcus neoformans. mBio 2019; 10:mBio.01952-19. [PMID: 31822582 PMCID: PMC6904872 DOI: 10.1128/mbio.01952-19] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Echinocandins show fungicidal activity against common invasive mycoses but are ineffective against cryptococcosis. The underlying mechanism for echinocandin resistance in Cryptococcus neoformans remains poorly understood but has been shown to involve Cdc50, the regulatory subunit of lipid flippase. In a forward genetic screen for cdc50Δ suppressor mutations that are caspofungin resistant, we identified Crm1 (caspofungin resistant mutation 1), a homolog of mechanosensitive channel proteins, and showed that crm1Δ restored caspofungin resistance in cdc50Δ cells. Caspofungin-treated cdc50Δ cells exhibited abnormally high intracellular calcium levels ([Ca2+]c) and heightened activation of the calcineurin pathway. Deletion of CRM1 in the cdc50Δ background normalized the abnormally high [Ca2+]c. Cdc50 interacts with Crm1 to maintain cellular calcium homeostasis. Analysis of chitin/chitosan content showed that deleting CRM1 reversed the decreased chitosan production of cdc50Δ cells. Together, these results demonstrate that Cdc50 and Crm1 regulation of the calcineurin pathway and cytoplasmic calcium homeostasis may underlie caspofungin resistance in C. neoformans IMPORTANCE Cryptococcus neoformans is the leading cause of fungal meningitis, accounting for ∼15% of HIV/AIDS-related deaths, but treatment options for cryptococcosis are limited. Echinocandins are the newest fungicidal drug class introduced but are ineffective in treating cryptococcosis. Our previous study identified the lipid flippase subunit Cdc50 as a contributor to echinocandin resistance in C. neoformans Here, we further elucidated the mechanism of Cdc50-mediated caspofungin drug resistance. We discovered that Cdc50 interacts with the mechanosensitive calcium channel protein Crm1 to regulate calcium homeostasis and caspofungin resistance via calcium/calcineurin signaling. These results provide novel insights into echinocandin resistance in this pathogen, which may lead to new treatment options, as well as inform echinocandin resistance mechanisms in other fungal organisms and, hence, advance our understanding of modes of antifungal drug susceptibility and resistance.
Collapse
|
31
|
In Vitro Interactions of Amphotericin B Combined with Non-antifungal Agents Against Rhodotorula mucilaginosa Strains. Mycopathologia 2019; 184:35-43. [DOI: 10.1007/s11046-019-0317-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 01/02/2019] [Indexed: 10/27/2022]
|
32
|
Zhang M, Yang X, Wang D, Yu C, Sun S. Antifungal activity of immunosuppressants used alone or in combination with fluconazole. J Appl Microbiol 2018; 126:1304-1317. [PMID: 30307675 DOI: 10.1111/jam.14126] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 09/07/2018] [Accepted: 09/29/2018] [Indexed: 01/26/2023]
Abstract
Fungal infections remain a challenge to clinicians due to the limited available antifungals. With the increasing use of antifungals in clinical practice, drug resistance has been emerging continuously, especially to fluconazole (FLC). Thus, a search for new antifungals and approaches to overcome antifungal resistance is needed. However, the development of new antifungals is usually costly and time consuming; discovering the antifungal activity of non-antifungal agents is one way to address these problems. Interestingly, some researchers have demonstrated that several classes of immunosuppressants (calcineurin inhibitors, glucocorticoids, etc) also displayed potent antifungal activity when used alone or in combination with antifungals, especially with FLC. Some of them could increase FLC's susceptibility against resistant Candida albicans significantly reversing fungal resistance to FLC. This article reviews the antifungal activities of immunosuppressants used alone or in combination with antifungals and their potential antifungal mechanisms that have been discovered so far. Although immunosuppressive agents have been identified as risk factors for fungal infection, we believe these findings are very important for overcoming drug resistance and developing new antifungals.
Collapse
Affiliation(s)
- M Zhang
- School of Pharmaceutical Sciences, Taishan Medical University, Taian, Shandong Province, China
| | - X Yang
- Department of Pharmacy, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong Province, China
| | - D Wang
- School of Pharmaceutical Sciences, Taishan Medical University, Taian, Shandong Province, China
| | - C Yu
- Department of Pharmacy, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong Province, China
| | - S Sun
- Department of Pharmacy, Qianfoshan Hospital Affiliated to Shandong University, Jinan, Shandong Province, China
| |
Collapse
|
33
|
Abstract
Candida tropicalis is one of the most important human fungal pathogens causing superficial infections in locations such as the oral mucosa and genital tract, as well as systemic infections with high mortality. In its sister species Candida albicans, the cyclic AMP/protein kinase A (cAMP/PKA) pathway regulates fungal adhesion and dimorphism, both of which correlate closely with virulence. CaTpk1 and CaTpk2, the catalytic subunits of PKA, not only share redundant functions in hyphal growth, adhesion, and biofilm formation, but also have distinct roles in stress responses and pathogenesis, respectively. However, studies on PKA in the emerging fungal pathogen C. tropicalis are limited. Our results suggest that Tpk1 is involved in cell wall integrity and drug tolerance. The tpk2/tpk2 mutants, which have no protein kinase A activity, have reduced hyphal growth and adhesion. In addition, the tpk1/tpk1 tpk2/tpk2 double deletion mutant demonstrated delayed growth and impaired hyphal formation. In a murine model of systemic infection, both TPK1 and TPK2 were required for full virulence. We further found that EFG1 and HWP1 expression is regulated by PKA, while BCR1, FLO8, GAL4, and RIM101 are upregulated in the tpk1/tpk1 tpk2/tpk2 mutant. This study demonstrates that Tpk1 is involved in drug tolerance and cell wall integrity, while Tpk2 serves as a key regulator in dimorphism and adhesion. Both Tpk1 and Tpk2 are required for growth and full virulence in C. tropicalis.
Collapse
Affiliation(s)
- Chi-Jan Lin
- a Department of Plant Pathology and Microbiology , National Taiwan University , Taipei , Taiwan
| | - Chia-Yen Wu
- a Department of Plant Pathology and Microbiology , National Taiwan University , Taipei , Taiwan
| | - Shang-Jie Yu
- a Department of Plant Pathology and Microbiology , National Taiwan University , Taipei , Taiwan
| | - Ying-Lien Chen
- a Department of Plant Pathology and Microbiology , National Taiwan University , Taipei , Taiwan
| |
Collapse
|
34
|
Lin CJ, Chen YL. Conserved and Divergent Functions of the cAMP/PKA Signaling Pathway in Candida albicans and Candida tropicalis. J Fungi (Basel) 2018; 4:E68. [PMID: 29890663 PMCID: PMC6023519 DOI: 10.3390/jof4020068] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 05/28/2018] [Accepted: 06/07/2018] [Indexed: 01/03/2023] Open
Abstract
Fungal species undergo many morphological transitions to adapt to changing environments, an important quality especially in fungal pathogens. For decades, Candida albicans has been one of the most prevalent human fungal pathogens, and recently, the prevalence of Candida tropicalis as a causative agent of candidiasis has increased. In C. albicans, the ability to switch between yeast and hyphal forms is thought to be a key virulence factor and is regulated by multiple signaling cascades—including the cyclic adenosine monophosphate/protein kinase A (cAMP/PKA), calcineurin, high-osmolarity glycerol (HOG), and mitogen-activated protein kinases (MAPK) signaling pathways—upon receiving environmental cues. The cAMP/PKA signaling pathway also triggers white-opaque switching in C. albicans. However, studies on C. tropicalis morphogenesis are limited. In this minireview, we discuss the regulation of the yeast-hypha transition, virulence, and white-opaque switching through the cAMP/PKA pathway in the closely related species C. albicans and C. tropicalis.
Collapse
Affiliation(s)
- Chi-Jan Lin
- Department of Plant Pathology and Microbiology, National Taiwan University, 10617 Taipei, Taiwan.
| | - Ying-Lien Chen
- Department of Plant Pathology and Microbiology, National Taiwan University, 10617 Taipei, Taiwan.
| |
Collapse
|
35
|
Deletion of ADA2 Increases Antifungal Drug Susceptibility and Virulence in Candida glabrata. Antimicrob Agents Chemother 2018; 62:AAC.01924-17. [PMID: 29311082 DOI: 10.1128/aac.01924-17] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 12/15/2017] [Indexed: 12/23/2022] Open
Abstract
Candida glabrata, the second most frequent cause of candidiasis after Candida albicans, is an emerging human fungal pathogen that is intrinsically drug tolerant. Currently, studies of C. glabrata genes involved in drug tolerance are limited. Ada2, a component serving as a transcription adaptor of the Spt-Ada-Gcn5 acetyltransferase (SAGA) complex, is required for antifungal drug tolerance and virulence in C. albicans However, its roles in C. glabrata remain elusive. In this study, we found that ada2 mutants demonstrated severe growth defects at 40°C but only mild defects at 37°C or 25°C. In addition, C. glabrata ada2 mutants exhibited pleiotropic phenotypes, including susceptibility to three classes of antifungal drugs (i.e., azoles, echinocandins, and polyenes) and cell wall-perturbing agents but resistance to the endoplasmic reticulum stressor tunicamycin. According to RNA sequence analysis, the expression of 43 genes was downregulated and the expression of 442 genes was upregulated in the ada2 mutant compared to their expression in the wild type. C. glabrata ADA2, along with its downstream target ERG6, controls antifungal drug tolerance and cell wall integrity. Surprisingly, ada2 mutants were hypervirulent in a murine model of systemic infection, possibly due to the upregulation of multiple adhesin-like genes, increased agar invasion, and overstimulation of murine tumor necrosis factor alpha production.
Collapse
|
36
|
Dissecting the Roles of the Calcineurin Pathway in Unisexual Reproduction, Stress Responses, and Virulence in Cryptococcus deneoformans. Genetics 2017; 208:639-653. [PMID: 29233811 DOI: 10.1534/genetics.117.300422] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 12/07/2017] [Indexed: 01/12/2023] Open
Abstract
The Ca2+/calmodulin-dependent protein phosphatase calcineurin orchestrates sexual reproduction, stress responses, and virulence via branched downstream pathways in the opportunistic human fungal pathogen Cryptococcus neoformans The calcineurin-binding protein Cbp1, the calcineurin temperature suppressor Cts1, the calcineurin-responsive zinc finger transcription factor Crz1, and the calcineurin targets Pbp1, Tif3, and Puf4, all function downstream of calcineurin to orchestrate distinct cellular processes. To elucidate how the calcineurin pathway regulatory network governs unisexual reproduction, stress responses, and virulence, we have analyzed the self-filamentous C. deneoformans strain, XL280α, and generated double mutants of these calcineurin downstream genes. We demonstrated that calcineurin governs unisexual reproduction at different sexual developmental stages, in which the initiation of the yeast-hyphal morphological transition is independent of Crz1, whereas the sporulation process is dependent on Crz1. Calcineurin-dependent unisexual reproduction is independent of the pheromone response pathway. Crz1 synergistically interacts with different calcineurin downstream targets in responding to ER, high-calcium, and cell wall stresses. We observed a widespread synergy suggesting that these proteins function in complex branched pathways downstream of calcineurin with some functional redundancy, which may allow efficient signaling network rewiring within the pathway for prompt adaptation to changing environments. Finally, we showed that deletion of PBP1 or TIF3 in the cna1∆ mutant background conferred a modest level of growth tolerance at 37°, but that the cna1∆ pbp1∆ and cna1∆ tif3∆ double mutants were both avirulent, suggesting that calcineurin may control virulence via mechanisms beyond thermotolerance.
Collapse
|
37
|
Zuza-Alves DL, Silva-Rocha WP, Chaves GM. An Update on Candida tropicalis Based on Basic and Clinical Approaches. Front Microbiol 2017; 8:1927. [PMID: 29081766 PMCID: PMC5645804 DOI: 10.3389/fmicb.2017.01927] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 09/21/2017] [Indexed: 01/12/2023] Open
Abstract
Candida tropicalis has emerged as one of the most important Candida species. It has been widely considered the second most virulent Candida species, only preceded by C. albicans. Besides, this species has been recognized as a very strong biofilm producer, surpassing C. albicans in most of the studies. In addition, it produces a wide range of other virulence factors, including: adhesion to buccal epithelial and endothelial cells; the secretion of lytic enzymes, such as proteinases, phospholipases, and hemolysins, bud-to-hyphae transition (also called morphogenesis) and the phenomenon called phenotypic switching. This is a species very closely related to C. albicans and has been easily identified with both phenotypic and molecular methods. In addition, no cryptic sibling species were yet described in the literature, what is contradictory to some other medically important Candida species. C. tropicalis is a clinically relevant species and may be the second or third etiological agent of candidemia, specifically in Latin American countries and Asia. Antifungal resistance to the azoles, polyenes, and echinocandins has already been described. Apart from all these characteristics, C. tropicalis has been considered an osmotolerant microorganism and this ability to survive to high salt concentration may be important for fungal persistence in saline environments. This physiological characteristic makes this species suitable for use in biotechnology processes. Here we describe an update of C. tropicalis, focusing on all these previously mentioned subjects.
Collapse
Affiliation(s)
| | | | - Guilherme M. Chaves
- Laboratory of Medical and Molecular Mycology, Department of Clinical and Toxicological Analyses, Federal University of Rio Grande do Norte, Natal, Brazil
| |
Collapse
|
38
|
Zuza-Alves DL, de Medeiros SSTQ, de Souza LBFC, Silva-Rocha WP, Francisco EC, de Araújo MCB, Lima-Neto RG, Neves RP, Melo ASDA, Chaves GM. Evaluation of Virulence Factors In vitro, Resistance to Osmotic Stress and Antifungal Susceptibility of Candida tropicalis Isolated from the Coastal Environment of Northeast Brazil. Front Microbiol 2016; 7:1783. [PMID: 27895625 PMCID: PMC5108815 DOI: 10.3389/fmicb.2016.01783] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 10/24/2016] [Indexed: 12/01/2022] Open
Abstract
Several studies have been developed regarding human health risks associated with the recreational use of beaches contaminated with domestic sewage. These wastes contain various micro-organisms, including Candida tropicalis. In this context, the objective of this study was to characterize C. tropicalis isolates from the sandy beach of Ponta Negra, Natal, Rio Grande do Norte, Brazil, regarding the expression of in vitro virulence factors, adaptation to osmotic stress and susceptibility to antifungal drugs. We analyzed 62 environmental isolates and observed a great variation among them for the various virulence factors evaluated. In general, environmental isolates were more adherent to human buccal epithelial cells (HBEC) than C. tropicalis ATCC13803 reference strain, and they also showed increased biofilm production. Most of the isolates presented wrinkled phenotypes on Spider medium (34 isolates, 54.8%). The majority of the isolates also showed higher proteinase production than control strains, but low phospholipase activity. In addition, 35 isolates (56.4%) had high hemolytic activity (hemolysis index > 0.55). With regard to C. tropicalis resistance to osmotic stress, 85.4% of the isolates were able to grow in a liquid medium containing 15% sodium chloride. The strains were highly resistant to the azoles tested (fluconazole, voriconazole and itraconazole). Fifteen strains were resistant to the three azoles tested (24.2%). Some strains were also resistant to amphotericin B (14 isolates; 22.6%), while all of them were susceptible for the echinocandins tested, except for a single strain of intermediate susceptibility to micafungin. Our results demonstrate that C. tropicalis isolated from the sand can fully express virulence attributes and showed a high persistence capacity on the coastal environment; in addition of showing high minimal inhibitory concentrations to several antifungal drugs used in current clinical practice, demonstrating that environmental isolates may have pathogenic potential.
Collapse
Affiliation(s)
- Diana L Zuza-Alves
- Medical and Molecular Micology Laboratory, Department of Clinical and Toxicological Analyses, Federal University of Rio Grande do Norte Natal, Brazil
| | - Sayama S T Q de Medeiros
- Medical and Molecular Micology Laboratory, Department of Clinical and Toxicological Analyses, Federal University of Rio Grande do Norte Natal, Brazil
| | - Luanda B F C de Souza
- Medical and Molecular Micology Laboratory, Department of Clinical and Toxicological Analyses, Federal University of Rio Grande do Norte Natal, Brazil
| | - Walicyranison P Silva-Rocha
- Medical and Molecular Micology Laboratory, Department of Clinical and Toxicological Analyses, Federal University of Rio Grande do Norte Natal, Brazil
| | - Elaine C Francisco
- Department of Mycology, Federal University of Pernambuco São Paulo, Brazil
| | - Maria C B de Araújo
- Department of Oceanography and Limnology, Federal University of Rio Grande do Norte Natal, Brazil
| | | | - Rejane P Neves
- Department of Mycology, Federal University of Pernambuco, Recife Pernambuco, Brazil
| | | | - Guilherme M Chaves
- Medical and Molecular Micology Laboratory, Department of Clinical and Toxicological Analyses, Federal University of Rio Grande do Norte Natal, Brazil
| |
Collapse
|
39
|
Zhang L, Chen X, Chen Z, Wang Z, Jiang S, Li L, Pötter M, Shen W, Fan Y. Development of an efficient genetic manipulation strategy for sequential gene disruption and expression of different heterologous GFP genes in Candida tropicalis. Appl Microbiol Biotechnol 2016; 100:9567-9580. [PMID: 27522195 DOI: 10.1007/s00253-016-7762-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Revised: 07/22/2016] [Accepted: 08/01/2016] [Indexed: 11/29/2022]
Abstract
The diploid yeast Candida tropicalis, which can utilize n-alkane as a carbon and energy source, is an attractive strain for both physiological studies and practical applications. However, it presents some characteristics, such as rare codon usage, difficulty in sequential gene disruption, and inefficiency in foreign gene expression, that hamper strain improvement through genetic engineering. In this work, we present a simple and effective method for sequential gene disruption in C. tropicalis based on the use of an auxotrophic mutant host defective in orotidine monophosphate decarboxylase (URA3). The disruption cassette, which consists of a functional yeast URA3 gene flanked by a 0.3 kb gene disruption auxiliary sequence (gda) direct repeat derived from downstream or upstream of the URA3 gene and of homologous arms of the target gene, was constructed and introduced into the yeast genome by integrative transformation. Stable integrants were isolated by selection for Ura+ and identified by PCR and sequencing. The important feature of this construct, which makes it very attractive, is that recombination between the flanking direct gda repeats occurs at a high frequency (10-8) during mitosis. After excision of the URA3 marker, only one copy of the gda sequence remains at the recombinant locus. Thus, the resulting ura3 strain can be used again to disrupt a second allelic gene in a similar manner. In addition to this effective sequential gene disruption method, a codon-optimized green fluorescent protein-encoding gene (GFP) was functionally expressed in C. tropicalis. Thus, we propose a simple and reliable method to improve C. tropicalis by genetic manipulation.
Collapse
Affiliation(s)
- Lihua Zhang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - Xianzhong Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.
| | - Zhen Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - Zezheng Wang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - Shan Jiang
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - Li Li
- Evonik Degussa (China) Co. Ltd., Shanghai Branch, Shanghai, 201108, China
| | - Markus Pötter
- Evonik Degussa (China) Co. Ltd., Shanghai Branch, Shanghai, 201108, China
| | - Wei Shen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| | - You Fan
- Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China
| |
Collapse
|
40
|
Significance of hyphae formation in virulence of Candida tropicalis and transcriptomic analysis of hyphal cells. Microbiol Res 2016; 192:65-72. [PMID: 27664724 DOI: 10.1016/j.micres.2016.06.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 06/02/2016] [Accepted: 06/04/2016] [Indexed: 01/12/2023]
Abstract
Recently, the proportion of Candida tropicalis in clinical isolates has significantly increased. Some C. tropicalis strains colonize the skin or mucosal surfaces as commensals; others trigger invasive infection. To date, the pathogenicity of C. tropicalis has not been thoroughly researched. This study reports several virulence factors, including biofilm and hyphae formation, proteinase, phospholipase, lipase and hemolytic activity, in 52 clinical isolates of C. tropicalis collected from five hospitals in four provinces of China. Some C. tropicalis tended to produce more hyphae than others in the same circumstance. Six C. tropicalis strains with different morphologies were injected into mice via the tail vein, and the survival proportions and fungal burdens of the strains were evaluated. Hyphal production by C. tropicalis was associated with stronger virulence. RNA sequencing revealed that C. tropicalis with more hyphae up-regulated several genes involved in morphological differentiation and oxidative response, including IF2, Atx1, and Sod2. It appears that hyphal formation plays a vital role in the pathogenicity of C. tropicalis, and interacts with the oxidative stress response to strengthen the organism's virulence.
Collapse
|
41
|
Morais-Braga MFB, Carneiro JNP, Machado AJT, Sales DL, Brito DI, Albuquerque RS, Boligon AA, Athayde ML, Calixto Júnior JT, Souza DSL, Lima EO, Menezes IRA, Costa JGM, Ferreira FS, Coutinho HDM. High-Performance Liquid Chromatography-Diodic Array Detector, Fungistatic, and Anti-Morphogenical Analysis of Extracts from Psidium brownianum Mart. ex DC. Against Yeasts of the Genus Candida. INTERNATIONAL JOURNAL OF FOOD PROPERTIES 2016. [DOI: 10.1080/10942912.2015.1079786] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
| | - Joara N. P. Carneiro
- Department of Biological Sciences, Regional University of Cariri, Crato, Ceará, Brazil
| | - Antonio J. T. Machado
- Department of Biological Sciences, Regional University of Cariri, Crato, Ceará, Brazil
| | - Débora L. Sales
- Department of Biological Sciences, Regional University of Cariri, Crato, Ceará, Brazil
| | - Dara I.V. Brito
- Department of Biological Chemistry, Regional University of Cariri, Crato, Ceará, Brazil
| | | | - Aline A. Boligon
- Department of Industrial Pharmacy, Federal University of Santa Maria, Santa Maria, Rio Grande do sul, Brazil
| | - Margareth L. Athayde
- Department of Industrial Pharmacy, Federal University of Santa Maria, Santa Maria, Rio Grande do sul, Brazil
| | | | - Djair S. L. Souza
- ESAM, Federal University of the Semi Arid, Mossoró, Rio Grande do Norte, Brazil
| | - Edeltrudes O. Lima
- Laboratory of Micology, Federal University of Paraíba, João Pessoa, Paraiba, Brazil
| | - Irwin R. A. Menezes
- Department of Biological Chemistry, Regional University of Cariri, Crato, Ceará, Brazil
| | - José G. M. Costa
- Department of Biological Chemistry, Regional University of Cariri, Crato, Ceará, Brazil
| | - Felipe S. Ferreira
- Department of Biological Chemistry, Regional University of Cariri, Crato, Ceará, Brazil
| | | |
Collapse
|
42
|
Liu S, Yue L, Gu W, Li X, Zhang L, Sun S. Synergistic Effect of Fluconazole and Calcium Channel Blockers against Resistant Candida albicans. PLoS One 2016; 11:e0150859. [PMID: 26986478 PMCID: PMC4795682 DOI: 10.1371/journal.pone.0150859] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 02/19/2016] [Indexed: 11/18/2022] Open
Abstract
Candidiasis has increased significantly recently that threatens patients with low immunity. However, the number of antifungal drugs on the market is limited in comparison to the number of available antibacterial drugs. This fact, coupled with the increased frequency of fungal resistance, makes it necessary to develop new therapeutic strategies. Combination drug therapy is one of the most widely used and effective strategy to alleviate this problem. In this paper, we were aimed to evaluate the combined antifungal effects of four CCBs (calcium channel blockers), amlodipine (AML), nifedipine (NIF), benidipine (BEN) and flunarizine (FNZ) with fluconazole against C. albicans by checkerboard and time-killing method. In addition, we determined gene (CCH1, MID1, CNA1, CNB1, YVC1, CDR1, CDR2 and MDR1) expression by quantitative PCR and investigated the efflux pump activity of resistant candida albicans by rhodamine 6G assay to reveal the potential mechanisms. Finally, we concluded that there was a synergy when fluconazole combined with the four tested CCBs against resistant strains, with fractional inhibitory concentration index (FICI) <0.5, but no interaction against sensitive strains (FICI = 0.56 ~ 2). The mechanism studies revealed that fluconazole plus amlodipine caused down-regulating of CNA1, CNB1 (encoding calcineurin) and YVC1 (encoding calcium channel protein in vacuole membrane).
Collapse
Affiliation(s)
- Shuyuan Liu
- School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, Shandong Province, People’s Republic of China
- Department of Pharmacy, Ordos Central Hospital, Ordos, 017000, Inner Mongolia, People’s Republic of China
| | - Longtao Yue
- Translational Medicine Research Centre, Qianfoshan Hospital Affiliated to Shandong University, Jinan, 250014, Shandong Province, People’s Republic of China
| | - Wenrui Gu
- School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, Shandong Province, People’s Republic of China
| | - Xiuyun Li
- School of Pharmaceutical Sciences, Shandong University, Jinan, 250012, Shandong Province, People’s Republic of China
| | - Liuping Zhang
- School of Pharmaceutical Sciences, Taishan Medical University, taian, 271000, Shandong Province, People’s Republic of China
| | - Shujuan Sun
- Department of Pharmacy, Qianfoshan Hospital Affiliated to Shandong University, Jinan, 250014, Shandong Province, People’s Republic of China
- * E-mail:
| |
Collapse
|
43
|
Zhang SH. The Genetic Basis of Abiotic Stress Resistance in Extremophilic Fungi: The Genes Cloning and Application. FUNGAL APPLICATIONS IN SUSTAINABLE ENVIRONMENTAL BIOTECHNOLOGY 2016. [DOI: 10.1007/978-3-319-42852-9_2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
44
|
Guerrero HT, Espinosa IM, Ibarra MG, Aguirre García M. Distribution of <i>Candida</i> Species and Molecular Typing of <i>C. albicans</i> Isolates in a Mexico City Tertiary Care Hospital from 2011 to 2013. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/ojmm.2016.62010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
45
|
Characterization of Virulence-Related Phenotypes in Candida Species of the CUG Clade. EUKARYOTIC CELL 2015; 14:931-40. [PMID: 26150417 DOI: 10.1128/ec.00062-15] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 06/25/2015] [Indexed: 11/20/2022]
Abstract
Candida species cause a variety of mucosal and invasive infections and are, collectively, the most important human fungal pathogens in the developed world. The majority of these infections result from a few related species within the "CUG clade," so named because they use a nonstandard translation for that codon. Some members of the CUG clade, such as Candida albicans, present significant clinical problems, whereas others, such as Candida (Meyerozyma) guilliermondii, are uncommon in patients. The differences in incidence rates are imperfectly correlated with virulence in animal models of infection, but comparative analyses that might provide an explanation for why some species are effective pathogens and others are not have been rare or incomplete. To better understand the phenotypic basis for these differences, we characterized eight CUG clade species--C. albicans, C. dubliniensis, C. tropicalis, C. parapsilosis, Clavispora lusitaniae, M. guilliermondii, Debaryomyces hansenii, and Lodderomyces elongisporus--for host-relevant phenotypes, including nutrient utilization, stress tolerance, morphogenesis, interactions with phagocytes, and biofilm formation. Two species deviated from expectations based on animal studies and human incidence. C. dubliniensis was quite robust, grouping in nearly all assays with the most virulent species, C. albicans and C. tropicalis, whereas C. parapsilosis was substantially less fit than might be expected from its clinical importance. These findings confirm the utility of in vitro measures of virulence and provide insight into the evolution of virulence in the CUG clade.
Collapse
|
46
|
Yesudhason BL, Mohanram K. Candida tropicalis as a Predominant Isolate from Clinical Specimens and its Antifungal Susceptibility Pattern in a Tertiary Care Hospital in Southern India. J Clin Diagn Res 2015; 9:DC14-6. [PMID: 26393128 PMCID: PMC4572959 DOI: 10.7860/jcdr/2015/13460.6208] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 06/12/2015] [Indexed: 01/05/2023]
Abstract
BACKGROUND The incidence of infections caused by Candida species has increased considerably over the past three decades mainly due to the rise of the AIDS epidemic, an increasingly aged population, higher numbers of immunocompromised patients and the more widespread use of indwelling medical devices. Candida tropicalis is emerging pathogenic yeast among non-albicans species. Recently drug-resistant C.tropicalis was also reported in hospitals. AIM AND OBJECTIVE The present study aimed to isolate and speciate C. tropicalis from various clinical samples and to determine its antifungal susceptibility profile. MATERIALS AND METHODS Clinical samples such as urine, blood, exudates and vaginal swab which were submitted to the Microbiology laboratory during the year 2013 were screened for the growth of Candidia species, which then identified as C.tropicalis by the routine microbiological procedures such as germ tube formation, assimilation and fermentation of sugars and colony color on HICHROM Candida agar. Antifungal susceptibility was performed by disc diffusion method with the drugs Amphotericin-B, Itraconazole, Ketaconazole and Fluconazole on C. tropicalis isolates. RESULTS A total number of 112 Candida isolates were isolated during the year 2012 from various clinical specimens. Among them 61 (54.3%) were identified as C.tropicalis. All the C. tropicalis isolates were sensitive to Amphotericin-B (100%) but 23 isolates (37.7%) were resistant to Fluconazole. CONCLUSION We conclude that identification of Candida species is important to know the prevalent species in the clinical setup and routine antifungal susceptibility should be performed to avoid inappropriate treatment.
Collapse
Affiliation(s)
- Binesh Lal Yesudhason
- Associate Professor, Department of Clinical Microbiology, Christian Medical College, Vellore, India
| | - Kalyani Mohanram
- Professor, Department of Microbiology, Matha Medical College, Thandalam, Chennai, India
| |
Collapse
|
47
|
Yu SJ, Chang YL, Chen YL. Calcineurin signaling: lessons from Candida species. FEMS Yeast Res 2015; 15:fov016. [DOI: 10.1093/femsyr/fov016] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/06/2015] [Indexed: 12/24/2022] Open
|