1
|
Hady RE, Fattouh N, Finianos M, Bitar I, Husni R, Khalaf R. Phenotypic and Genotypic Characterization of Candida parapsilosis complex isolates from a Lebanese Hospital. RESEARCH SQUARE 2024:rs.3.rs-4169036. [PMID: 38903078 PMCID: PMC11188110 DOI: 10.21203/rs.3.rs-4169036/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
The opportunistic fungal pathogen Candida parapsilosis is a major causative agent of candidiasis leading to death in immunocompromised individuals. Azoles are the first line of defense in treatment by inhibiting ERG11, involved in the synthesis of ergosterol, the main sterol fungal sterol. Resistance to azoles is on the increase worldwide including in Lebanon. The purpose of this study is to characterize nine hospital isolates labeled as C. parapsilosis: four resistant and five sensitive to fluconazole. Phenotypic characterization was achieved through a battery of tests that target pathogenicity attributes such as virulence, biofilm formation, stress resistance, and ergosterol content. Genotypic analysis was done through whole genome sequencing to mutations in key virulence and resistance genes. Phylogenetic comparison was performed to determine strain relatedness and clonality. Genomic data and phylogenetic analysis revealed that three of the nine C. parapsilosis isolates were misidentified; two as C. orthopsilosis and C. metapsilosis belonging to the C. parapsilosis complex, while the third was C. albicans. Moreover, several known and novel mutations in key drug resistance and virulence genes were identified such as ERG11, ERG3, ERG6, CDR1, and FAS2. Phylogenetic analysis revealed a high degree of relatedness and clonality within our C. parapsilosis isolates. Our results showed that resistant isolates had no increased ergosterol content, no statistically significant difference in virulence, but exhibited an increase in biofilm content compared to the sensitive isolates. In conclusion, our study, the first of its kind in Lebanon, suggests several mechanisms of antifungal drug resistance in C. parapsilosis hospital isolates.
Collapse
Affiliation(s)
| | | | | | | | - Rola Husni
- Lebanese American University School of Medicine
| | - Roy Khalaf
- Lebanese American University - Byblos Campus
| |
Collapse
|
2
|
Ahmady L, Gothwal M, Mukkoli MM, Bari VK. Antifungal drug resistance in Candida: a special emphasis on amphotericin B. APMIS 2024; 132:291-316. [PMID: 38465406 DOI: 10.1111/apm.13389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 02/12/2024] [Indexed: 03/12/2024]
Abstract
Invasive fungal infections in humans caused by several Candida species, increased considerably in immunocompromised or critically ill patients, resulting in substantial morbidity and mortality. Candida albicans is the most prevalent species, although the frequency of these organisms varies greatly according to geographic region. Infections with C. albicans and non-albicans Candida species have become more common, especially in the past 20 years, as a result of aging, immunosuppressive medication use, endocrine disorders, malnourishment, extended use of medical equipment, and an increase in immunogenic diseases. Despite C. albicans being the species most frequently associated with human infections, C. glabrata, C. parapsilosis, C. tropicalis, and C. krusei also have been identified. Several antifungal drugs with different modes of action are approved for use in clinical settings to treat fungal infections. However, due to the common eukaryotic structure of humans and fungi, only a limited number of antifungal drugs are available for therapeutic use. Furthermore, drug resistance in Candida species has emerged as a result of the growing use of currently available antifungal drugs against fungal infections. Amphotericin B (AmB), a polyene class of antifungal drugs, is mainly used for the treatment of serious systemic fungal infections. AmB interacts with fungal plasma membrane ergosterol, triggering cellular ion leakage via pore formation, or extracting the ergosterol from the plasma membrane inducing cellular death. AmB resistance is primarily caused by changes in the content or structure of ergosterol. This review summarizes the antifungal drug resistance exhibited by Candida species, with a special focus on AmB.
Collapse
Affiliation(s)
- Lailema Ahmady
- Department of Biochemistry, School of Basic Sciences, Central University of Punjab, Bathinda, India
| | - Manisha Gothwal
- Department of Biochemistry, School of Basic Sciences, Central University of Punjab, Bathinda, India
| | | | - Vinay Kumar Bari
- Department of Biochemistry, School of Basic Sciences, Central University of Punjab, Bathinda, India
| |
Collapse
|
3
|
Boyce KJ. The Microevolution of Antifungal Drug Resistance in Pathogenic Fungi. Microorganisms 2023; 11:2757. [PMID: 38004768 PMCID: PMC10673521 DOI: 10.3390/microorganisms11112757] [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: 10/11/2023] [Revised: 10/30/2023] [Accepted: 10/30/2023] [Indexed: 11/26/2023] Open
Abstract
The mortality rates of invasive fungal infections remain high because of the limited number of antifungal drugs available and antifungal drug resistance, which can rapidly evolve during treatment. Mutations in key resistance genes such as ERG11 were postulated to be the predominant cause of antifungal drug resistance in the clinic. However, recent advances in whole genome sequencing have revealed that there are multiple mechanisms leading to the microevolution of resistance. In many fungal species, resistance can emerge through ERG11-independent mechanisms and through the accumulation of mutations in many genes to generate a polygenic resistance phenotype. In addition, genome sequencing has revealed that full or partial aneuploidy commonly occurs in clinical or microevolved in vitro isolates to confer antifungal resistance. This review will provide an overview of the mutations known to be selected during the adaptive microevolution of antifungal drug resistance and focus on how recent advances in genome sequencing technology have enhanced our understanding of this process.
Collapse
Affiliation(s)
- Kylie J Boyce
- School of Science, RMIT University, Melbourne, VIC 3085, Australia
| |
Collapse
|
4
|
Asadzadeh M, Alfouzan W, Parker JE, Meis JF, Kelly SL, Joseph L, Ahmad S. Molecular Characterization and Sterol Profiles Identify Nonsynonymous Mutations in ERG2 as a Major Mechanism Conferring Reduced Susceptibility to Amphotericin B in Candida kefyr. Microbiol Spectr 2023; 11:e0147423. [PMID: 37358415 PMCID: PMC10434000 DOI: 10.1128/spectrum.01474-23] [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: 05/16/2023] [Accepted: 06/01/2023] [Indexed: 06/27/2023] Open
Abstract
The molecular basis of reduced susceptibility to amphotericin B (rs-AMB) among any yeasts is poorly defined. Genetic alterations in genes involved in ergosterol biosynthesis and total cell sterols were investigated among clinical Candida kefyr isolates. C. kefyr isolates (n = 81) obtained from 74 patients in Kuwait and identified by phenotypic and molecular methods were analyzed. An Etest was initially used to identify isolates with rs-AMB. Specific mutations in ERG2 and ERG6 involved in ergosterol biosynthesis were detected by PCR sequencing. Twelve selected isolates were also tested by the SensiTitre Yeast One (SYO), and total cell sterols were evaluated by gas chromatography-mass spectrometry and ERG3 and ERG11 sequencing. Eight isolates from 8 patients showed rs-AMB by Etest, including 2 isolates with additional resistance to fluconazole or to all three antifungals. SYO correctly identified 8 of 8 rs-AMB isolates. A nonsynonymous mutation in ERG2 was detected in 6 of 8 rs-AMB isolates but also in 3 of 73 isolates with a wild-type AMB pattern. One rs-AMB isolate contained a deletion (frameshift) mutation in ERG2. One or more nonsynonymous mutations was detected in ERG6 in 11 of 81 isolates with the rs-AMB or wild-type AMB pattern. Among 12 selected isolates, 2 and 2 isolates contained a nonsynonymous mutation(s) in ERG3 and ERG11, respectively. Ergosterol was undetectable in 7 of 8 rs-AMB isolates, and the total cell sterol profiles were consistent with loss of ERG2 function in 6 rs-AMB isolates and loss of ERG3 activity in another rs-AMB isolate. Our data showed that ERG2 is a major target conferring rs-AMB in clinical C. kefyr isolates. IMPORTANCE Some yeast species exhibit intrinsic resistance or rapidly acquire resistance to azole antifungals. Despite >50 years of clinical use, resistance to amphotericin B (AMB) among yeast species has been extremely rarely reported until recently. Reduced susceptibility to AMB (rs-AMB) among yeast species is, therefore, a matter of serious concern due to the availability of only four classes of antifungal drugs. Recent studies in Candida glabrata, Candida lusitaniae, and Candida auris have identified ERG genes involved in ergosterol biosynthesis as the major targets conferring rs-AMB. The results of this study also show that nonsynonymous mutations in ERG2 impair its function, abolish ergosterol from C. kefyr, and confer rs-AMB. Thus, rapid detection of rs-AMB among clinical isolates will help in proper management of invasive C. kefyr infections.
Collapse
Affiliation(s)
- Mohammad Asadzadeh
- Department of Microbiology, Faculty of Medicine, Kuwait University, Safat, Kuwait
| | - Wadha Alfouzan
- Department of Microbiology, Faculty of Medicine, Kuwait University, Safat, Kuwait
| | - Josie E. Parker
- Molecular Biosciences Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
| | - Jacques F. Meis
- Department of Medical Microbiology and Infectious Diseases, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands
- Center of Expertise in Mycology, Radboudumc, Canisius-Wilhelmina Hospital, Nijmegen, the Netherlands
- Department of Internal Medicine, Excellence Center for Medical Mycology, Faculty of Medicine, University Hospital Cologne, Cologne, Germany
| | - Steven L. Kelly
- Institute of Life Science, Faculty of Health, Medicine and Life Sciences, Swansea University, Swansea, Wales, United Kingdom
| | - Leena Joseph
- Department of Microbiology, Faculty of Medicine, Kuwait University, Safat, Kuwait
| | - Suhail Ahmad
- Department of Microbiology, Faculty of Medicine, Kuwait University, Safat, Kuwait
| |
Collapse
|
5
|
Sharma C, Kadosh D. Post-transcriptional control of antifungal resistance in human fungal pathogens. Crit Rev Microbiol 2023; 49:469-484. [PMID: 35634915 PMCID: PMC9766424 DOI: 10.1080/1040841x.2022.2080527] [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: 01/12/2022] [Revised: 05/10/2022] [Accepted: 05/17/2022] [Indexed: 11/03/2022]
Abstract
Global estimates suggest that over 300 million individuals of all ages are affected by serious fungal infections every year, culminating in about 1.7 million deaths. The societal and economic burden on the public health sector due to opportunistic fungal pathogens is quite significant, especially among immunocompromised patients. Despite the high clinical significance of these infectious agents, treatment options are limited with only three major classes of antifungal drugs approved for use. Clinical management of fungal diseases is further compromised by the emergence of antifungal resistant strains. Transcriptional and genetic mechanisms that control drug resistance in human fungal pathogens are well-studied and include drug target alteration, upregulation of drug efflux pumps as well as changes in drug affinity and abundance of target proteins. In this review, we highlight several recently discovered novel post-transcriptional mechanisms that control antifungal resistance, which involve regulation at the translational, post-translational, epigenetic, and mRNA stability levels. The discovery of many of these novel mechanisms has opened new avenues for the development of more effective antifungal treatment strategies and new insights, perspectives, and future directions that will facilitate this process are discussed.
Collapse
Affiliation(s)
- Cheshta Sharma
- Department of Microbiology, Immunology and Molecular Genetics University of Texas Health Science Center at San Antonio, San Antonio, TX
| | - David Kadosh
- Department of Microbiology, Immunology and Molecular Genetics University of Texas Health Science Center at San Antonio, San Antonio, TX
| |
Collapse
|
6
|
Lim HJ, Choi MJ, Byun SA, Won EJ, Park JH, Choi YJ, Choi HJ, Choi HW, Kee SJ, Kim SH, Shin MG, Lee SY, Kim MN, Shin JH. Whole-Genome Sequence Analysis of Candida glabrata Isolates from a Patient with Persistent Fungemia and Determination of the Molecular Mechanisms of Multidrug Resistance. J Fungi (Basel) 2023; 9:jof9050515. [PMID: 37233226 DOI: 10.3390/jof9050515] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/24/2023] [Accepted: 04/24/2023] [Indexed: 05/27/2023] Open
Abstract
Whole-genome sequencing (WGS) was used to determine the molecular mechanisms of multidrug resistance for 10 serial Candida glabrata bloodstream isolates obtained from a neutropenic patient during 82 days of amphotericin B (AMB) or echinocandin therapy. For WGS, a library was prepared and sequenced using a Nextera DNA Flex Kit (Illumina) and the MiseqDx (Illumina) instrument. All isolates harbored the same Msh2p substitution, V239L, associated with multilocus sequence type 7 and a Pdr1p substitution, L825P, that caused azole resistance. Of six isolates with increased AMB MICs (≥2 mg/L), three harboring the Erg6p A158fs mutation had AMB MICs ≥ 8 mg/L, and three harboring the Erg6p R314K, Erg3p G236D, or Erg3p F226fs mutation had AMB MICs of 2-3 mg/L. Four isolates harboring the Erg6p A158fs or R314K mutation had fluconazole MICs of 4-8 mg/L while the remaining six had fluconazole MICs ≥ 256 mg/L. Two isolates with micafungin MICs > 8 mg/L harbored Fks2p (I661_L662insF) and Fks1p (C499fs) mutations, while six isolates with micafungin MICs of 0.25-2 mg/L harbored an Fks2p K1357E substitution. Using WGS, we detected novel mechanisms of AMB and echinocandin resistance; we explored mechanisms that may explain the complex relationship between AMB and azole resistance.
Collapse
Affiliation(s)
- Ha Jin Lim
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
| | - Min Ji Choi
- Microbiological Analysis Team, Biometrology Group, Korea Research Institute of Standards and Science (KRISS), Daejeon 34113, Republic of Korea
| | - Seung A Byun
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
| | - Eun Jeong Won
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
- Department of Laboratory Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Joo Heon Park
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
| | - Yong Jun Choi
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
| | - Hyun-Jung Choi
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
| | - Hyun-Woo Choi
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
| | - Seung-Jung Kee
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
| | - Soo Hyun Kim
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
| | - Myung Geun Shin
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
| | - Seung Yeob Lee
- Department of Laboratory Medicine, Jeonbuk National University Medical School and Jeonbuk National University Hospital, Jeonju 54907, Republic of Korea
- Research Institute of Clinical Medicine of Jeonbuk National University-Biomedical Research Institute of Jeonbuk National University Hospital, Jeonju 54907, Republic of Korea
| | - Mi-Na Kim
- Department of Laboratory Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | - Jong Hee Shin
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju 61469, Republic of Korea
| |
Collapse
|
7
|
Elias D, Hervay NT, Jacko J, Morvova M, Valachovic M, Gbelska Y. Erg6p is essential for antifungal drug resistance, plasma membrane properties and cell wall integrity in Candida glabrata. FEMS Yeast Res 2022; 21:6680247. [PMID: 36047961 DOI: 10.1093/femsyr/foac045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/18/2022] [Accepted: 08/30/2022] [Indexed: 11/13/2022] Open
Abstract
ERG6 gene encodes C-24 methyltransferase, one of the specific enzymes that differ in mammalian and yeast sterol biosynthesis. To explore the function of CgErg6p in the yeast pathogen Candida glabrata, we have constructed the Cgerg6Δ deletion mutant. We found that C. glabrata cells lacking CgErg6p exhibit reduced susceptibility to both antifungal azoles and polyenes. The reduced content of ergosterol in the Cgerg6 deletion mutant was accompanied by increased expression of genes encoding the last steps of the ergosterol biosynthetic pathway. The absence of CgErg6p leads to plasma membrane hyperpolarization and decrease in its fluidity compared to the parental C. glabrata strain. The absence of sterols containing C-24 alkyls influenced the susceptibility of Cgerg6Δ mutant cells to alkali metal cations and several other metabolic inhibitors. Our results thus show that sterols lacking C-24 alkyls are not sufficient substitutes for maintaining yeast plasma membrane function. The absence of CgErg6p influences also the cell wall integrity and calcineurin signaling in C. glabrata.
Collapse
Affiliation(s)
- Daniel Elias
- Faculty of Natural Sciences, Department of Microbiology and Virology, Comenius University in Bratislava, Ilkovicova 6, 842 15 Bratislava, Slovak Republic
| | - Nora Toth Hervay
- Faculty of Natural Sciences, Department of Microbiology and Virology, Comenius University in Bratislava, Ilkovicova 6, 842 15 Bratislava, Slovak Republic
| | - Juraj Jacko
- Faculty of Mathematics, Physics and Informatics, Department of Nuclear Physics and Biophysics, Comenius University in Bratislava, Mlynska dolina, 842 48 Bratislava, Slovak Republic
| | - Marcela Morvova
- Faculty of Mathematics, Physics and Informatics, Department of Nuclear Physics and Biophysics, Comenius University in Bratislava, Mlynska dolina, 842 48 Bratislava, Slovak Republic
| | - Martin Valachovic
- Institute of Animal Biochemistry and Genetics CBS SAS, Dubravska cesta 9, 840 05 BratislavaSlovak Republic
| | - Yvetta Gbelska
- Faculty of Natural Sciences, Department of Microbiology and Virology, Comenius University in Bratislava, Ilkovicova 6, 842 15 Bratislava, Slovak Republic
| |
Collapse
|
8
|
Merdan O, Şişman AS, Aksoy SA, Kızıl S, Tüzemen NÜ, Yılmaz E, Ener B. Investigation of the Defective Growth Pattern and Multidrug Resistance in a Clinical Isolate of Candida glabrata Using Whole-Genome Sequencing and Computational Biology Applications. Microbiol Spectr 2022; 10:e0077622. [PMID: 35867406 PMCID: PMC9430859 DOI: 10.1128/spectrum.00776-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Accepted: 06/16/2022] [Indexed: 11/20/2022] Open
Abstract
Candida glabrata is increasingly isolated from blood cultures, and multidrug-resistant isolates have important implications for therapy. This study describes a cholesterol-dependent clinical C. glabrata isolate (ML72254) that did not grow without blood (containing cholesterol) on routine mycological media and that showed azole and amphotericin B (AmB) resistance. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) and whole-genome sequencing (WGS) were used for species identification. A modified Etest method (Mueller-Hinton agar supplemented with 5% sheep blood) was used for antifungal susceptibility testing. WGS data were processed via the Galaxy platform, and the genomic variations of ML72254 were retrieved. A computational biology workflow utilizing web-based applications (PROVEAN, AlphaFold Colab, and Missense3D) was constructed to predict possible deleterious effects of these missense variations on protein functions. The predictive ability of this workflow was tested with previously reported missense variations in ergosterol synthesis genes of C. glabrata. ML72254 was identified as C. glabrata sensu stricto with MALDI-TOF, and WGS confirmed this identification. The MICs of fluconazole, voriconazole, and amphotericin B were >256, >32, and >32 μg/mL, respectively. A novel frameshift mutation in the ERG1 gene (Pro314fs) and many missense variations were detected in the ergosterol synthesis genes. None of the missense variations in the ML72254 ergosterol synthesis genes were deleterious, and the Pro314fs mutation was identified as the causative molecular change for a cholesterol-dependent and multidrug-resistant phenotype. This study verified that web-based computational biology solutions can be powerful tools for examining the possible impacts of missense mutations in C. glabrata. IMPORTANCE In this study, a cholesterol-dependent C. glabrata clinical isolate that confers azole and AmB resistance was investigated using artificial intelligence (AI) technologies and cloud computing applications. This is the first of the known cholesterol-dependent C. glabrata isolate to be found in Turkey. Cholesterol-dependent C. glabrata isolates are rarely isolated in clinical samples; they can easily be overlooked during routine laboratory procedures. Microbiologists therefore need to be alert when discrepancies occur between microscopic examination and growth on routine media. In addition, because these isolates confer antifungal resistance, patient management requires extra care.
Collapse
Affiliation(s)
- Osman Merdan
- Department of Medical Microbiology, Faculty of Medicine, Bursa Uludağ University, Bursa, Turkey
| | - Ayşe Sena Şişman
- Department of Clinical Microbiology and Infectious Diseases, Faculty of Medicine, Bursa Uludağ University, Bursa, Turkey
| | - Seçil Ak Aksoy
- İnegöl Vocational School, Bursa Uludağ University, Bursa, Turkey
| | - Samet Kızıl
- Department of Medical Microbiology, Faculty of Medicine, Bursa Uludağ University, Bursa, Turkey
| | - Nazmiye Ülkü Tüzemen
- Department of Medical Microbiology, Faculty of Medicine, Bursa Uludağ University, Bursa, Turkey
| | - Emel Yılmaz
- Department of Clinical Microbiology and Infectious Diseases, Faculty of Medicine, Bursa Uludağ University, Bursa, Turkey
| | - Beyza Ener
- Department of Medical Microbiology, Faculty of Medicine, Bursa Uludağ University, Bursa, Turkey
| |
Collapse
|
9
|
Gupta H, Gupta P, Kairamkonda M, Poluri KM. Molecular investigations on Candida glabrata clinical isolates for pharmacological targeting. RSC Adv 2022; 12:17570-17584. [PMID: 35765448 PMCID: PMC9194923 DOI: 10.1039/d2ra02092k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 06/03/2022] [Indexed: 12/12/2022] Open
Abstract
Prevalence of drug resistant C. glabrata strains in hospitalized immune-compromised patients with invasive fungal infections has increased at an unexpected pace. This has greatly pushed researchers in identification of mutations/variations in clinical isolates for better assessment of the prevailing drug resistance trends and also for updating of antifungal therapy regime. In the present investigation, the clinical isolates of C. glabrata were comprehensively characterized at a molecular level using metabolic profiling and transcriptional expression analysis approaches in combination with biochemical, morphological and chemical profiling methods. Biochemically, significant variations in azole susceptibility, surface hydrophobicity, and oxidative stress generation were observed among the isolates as compared to wild-type. The 1H NMR profiling identified 18 differential metabolites in clinical strains compared to wild-type and were classified into five categories, that include: sugars (7), amino acids and their derivatives (7), nitrogen bases (3) and coenzymes (1). Transcriptional analysis of selective metabolic and regulatory enzymes established that the major differences were found in cell membrane stress, carbohydrate metabolism, amino acid biosynthesis, ergosterol pathway and turnover of nitrogen bases. This detailed molecular level/metabolic fingerprint study is a useful approach for differentiating pathogenic/clinical isolates to that of wild-type. This study comprehensively delineated the differential cellular pathways at a molecular level that have been re-wired by the pathogenic clinical isolates for enhanced pathogenicity and virulence traits. The clinical isolates of Candida glabrata were characterized and found to be different in terms of metabolic pathways that could be targeted for drug development.![]()
Collapse
Affiliation(s)
- Hrishikesh Gupta
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee (IIT-Roorkee) Roorkee-247667 Uttarakhand India
| | - Payal Gupta
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee (IIT-Roorkee) Roorkee-247667 Uttarakhand India
| | - Manikyaprabhu Kairamkonda
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee (IIT-Roorkee) Roorkee-247667 Uttarakhand India
| | - Krishna Mohan Poluri
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee (IIT-Roorkee) Roorkee-247667 Uttarakhand India .,Centre for Nanotechnology, Indian Institute of Technology Roorkee Roorkee-247667 Uttarakhand India
| |
Collapse
|
10
|
Dahiya S, Sharma N, Punia A, Choudhary P, Gulia P, Parmar VS, Chhillar AK. Antimycotic Drugs and their Mechanisms of Resistance to Candida Species. Curr Drug Targets 2021; 23:116-125. [PMID: 34551694 DOI: 10.2174/1389450122666210719124143] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 05/17/2021] [Accepted: 05/24/2021] [Indexed: 12/20/2022]
Abstract
Fungal infections have shown an upsurge in recent decades, which is mainly because of the increasing number of immunocompromised patients and the occurrence of invasive candidiasis has been found to be 7-15 fold greater than that of invasive aspergillosis. The genus Candida comprises more than 150 distinct species, however, only a few of them are found to be pathogenic to humans. Mortality rates of Candida species are found to be around 45% and the reasons for this intensified mortality are inefficient diagnostic techniques and unfitting initial treatment strategies. There are only a few antifungal drug classes that are employed for the remedy of invasive fungal infections. which include azoles, polyenes, echinocandins, and pyrimidine analogs. During the last 2-3 decades, the usage of antifungal drugs has increased several folds due to which the reports of escalating antifungal drug resistance have also been recorded. The resistance is mostly to the triazole- based compounds. Due to the occurrence of antifungal drug resistance, the success rates of treatment have been reduced as well as major changes have been observed in the frequency of fungal infections. In this review, we have summarized the major molecular mechanisms for the development of antifungal drug resistance.
Collapse
Affiliation(s)
- Sweety Dahiya
- Centre for Biotechnology, MaharshiDayanand University Rohtak, Haryana. India
| | - Namita Sharma
- Centre for Biotechnology, MaharshiDayanand University Rohtak, Haryana. India
| | - Aruna Punia
- Centre for Biotechnology, MaharshiDayanand University Rohtak, Haryana. India
| | - Pooja Choudhary
- Centre for Biotechnology, MaharshiDayanand University Rohtak, Haryana. India
| | - Prity Gulia
- Centre for Biotechnology, MaharshiDayanand University Rohtak, Haryana. India
| | - Virinder S Parmar
- Department of Chemistry and Environmental Science, Medgar Evers College, The City University of New York, 1638 Bedford Avenue, Brooklyn, NY 11225. India
| | - Anil K Chhillar
- Centre for Biotechnology, MaharshiDayanand University Rohtak, Haryana. India
| |
Collapse
|
11
|
Lotfali E, Fattahi A, Sayyahfar S, Ghasemi R, Rabiei MM, Fathi M, Vakili K, Deravi N, Soheili A, Toreyhi H, Shirvani F. A Review on Molecular Mechanisms of Antifungal Resistance in Candida glabrata: Update and Recent Advances. Microb Drug Resist 2021; 27:1371-1388. [PMID: 33956513 DOI: 10.1089/mdr.2020.0235] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Candida glabrata is the second frequent etiologic agent of mucosal and invasive candidiasis. Based on the recent developments in molecular methods, C. glabrata has been introduced as a complex composed of C. glabrata, Candida nivariensis, and Candida bracarensis. The four main classes of antifungal drugs effective against C. glabrata are pyrimidine analogs (flucytosine), azoles, echinocandins, and polyenes. Although the use of antifungal drugs is related to the predictable development of drug resistance, it is not clear why C. glabrata is able to rapidly resist against multiple antifungals in clinics. The enhanced incidence and antifungal resistance of C. glabrata and the high mortality and morbidity need more investigation regarding the resistance mechanisms and virulence associated with C. glabrata; additional progress concerning the drug resistance of C. glabrata has to be further prevented. The present review highlights the mechanism of resistance to antifungal drugs in C. glabrata.
Collapse
Affiliation(s)
- Ensieh Lotfali
- Department of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Azam Fattahi
- Center for Research and Training in Skin Diseases and Leprosy, Tehran University of Medical Sciences, Tehran, Iran
| | - Shirin Sayyahfar
- Research Center of Pediatric Infectious Diseases, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences, Tehran, Iran
| | - Reza Ghasemi
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Mahdi Rabiei
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mobina Fathi
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kimia Vakili
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Niloofar Deravi
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Amirali Soheili
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hossein Toreyhi
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fariba Shirvani
- Pediatric Infections Research Center, Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
12
|
Carolus H, Pierson S, Muñoz JF, Subotić A, Cruz RB, Cuomo CA, Van Dijck P. Genome-Wide Analysis of Experimentally Evolved Candida auris Reveals Multiple Novel Mechanisms of Multidrug Resistance. mBio 2021; 12:e03333-20. [PMID: 33820824 PMCID: PMC8092288 DOI: 10.1128/mbio.03333-20] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 02/12/2021] [Indexed: 12/12/2022] Open
Abstract
Candida auris is globally recognized as an opportunistic fungal pathogen of high concern, due to its extensive multidrug resistance (MDR). Still, molecular mechanisms of MDR are largely unexplored. This is the first account of genome-wide evolution of MDR in C. auris obtained through serial in vitro exposure to azoles, polyenes, and echinocandins. We show the stepwise accumulation of copy number variations and novel mutations in genes both known and unknown in antifungal drug resistance. Echinocandin resistance was accompanied by a codon deletion in FKS1 hot spot 1 and a substitution in FKS1 "novel" hot spot 3. Mutations in ERG3 and CIS2 further increased the echinocandin MIC. Decreased azole susceptibility was linked to a mutation in transcription factor TAC1b and overexpression of the drug efflux pump Cdr1, a segmental duplication of chromosome 1 containing ERG11, and a whole chromosome 5 duplication, which contains TAC1b The latter was associated with increased expression of ERG11, TAC1b, and CDR2 but not CDR1 The simultaneous emergence of nonsense mutations in ERG3 and ERG11 was shown to decrease amphotericin B susceptibility, accompanied with fluconazole cross-resistance. A mutation in MEC3, a gene mainly known for its role in DNA damage homeostasis, further increased the polyene MIC. Overall, this study shows the alarming potential for and diversity of MDR development in C. auris, even in a clade until now not associated with MDR (clade II), stressing its clinical importance and the urge for future research.IMPORTANCECandida auris is a recently discovered human fungal pathogen and has shown an alarming potential for developing multi- and pan-resistance toward all classes of antifungals most commonly used in the clinic. Currently, C. auris has been globally recognized as a nosocomial pathogen of high concern due to this evolutionary potential. So far, this is the first study in which the stepwise progression of multidrug resistance (MDR) in C. auris is monitored in vitro Multiple novel mutations in known resistance genes and genes previously not or vaguely associated with drug resistance reveal rapid MDR evolution in a C. auris clade II isolate. Additionally, this study shows that in vitro experimental evolution can be a powerful tool to discover new drug resistance mechanisms, although it has its limitations.
Collapse
Affiliation(s)
- Hans Carolus
- VIB Center for Microbiology, Leuven, Belgium
- Department of Biology, KU Leuven, Leuven, Belgium
| | | | - José F Muñoz
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - Ana Subotić
- VIB Center for Microbiology, Leuven, Belgium
- Department of Biology, KU Leuven, Leuven, Belgium
| | - Rita B Cruz
- Department of Biology, KU Leuven, Leuven, Belgium
| | | | - Patrick Van Dijck
- VIB Center for Microbiology, Leuven, Belgium
- Department of Biology, KU Leuven, Leuven, Belgium
| |
Collapse
|
13
|
Demin KA, Refeld AG, Bogdanova AA, Prazdnova EV, Popov IV, Kutsevalova OY, Ermakov AM, Bren AB, Rudoy DV, Chistyakov VA, Weeks R, Chikindas ML. Mechanisms of Candida Resistance to Antimycotics and Promising Ways to Overcome It: The Role of Probiotics. Probiotics Antimicrob Proteins 2021; 13:926-948. [PMID: 33738706 DOI: 10.1007/s12602-021-09776-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/09/2021] [Indexed: 12/12/2022]
Abstract
Pathogenic Candida and infections caused by those species are now considered as a serious threat to public health. The treatment of candidiasis is significantly complicated by the increasing resistance of pathogenic strains to current treatments and the stagnant development of new antimycotic drugs. Many species, such as Candida auris, have a wide range of resistance mechanisms. Among the currently used synthetic and semi-synthetic antifungal drugs, the most effective are azoles, echinocandins, polyenes, nucleotide analogs, and their combinations. However, the use of probiotic microorganisms and/or the compounds they produce is quite promising, although underestimated by modern pharmacology, to control the spread of pathogenic Candida species.
Collapse
Affiliation(s)
- Konstantin A Demin
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Aleksandr G Refeld
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Anna A Bogdanova
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Evgenya V Prazdnova
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Igor V Popov
- Center for Agrobiotechnology, Don State Technical University, Rostov-on-Don, Russia
| | | | - Alexey M Ermakov
- Center for Agrobiotechnology, Don State Technical University, Rostov-on-Don, Russia
| | - Anzhelica B Bren
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia.,Center for Agrobiotechnology, Don State Technical University, Rostov-on-Don, Russia
| | - Dmitry V Rudoy
- Center for Agrobiotechnology, Don State Technical University, Rostov-on-Don, Russia
| | - Vladimir A Chistyakov
- Academy of Biology and Biotechnology, Southern Federal University, Rostov-on-Don, Russia
| | - Richard Weeks
- Health Promoting Naturals Laboratory, School of Environmental and Biological Sciences, Rutgers State University, New Brunswick, NJ, USA
| | - Michael L Chikindas
- Center for Agrobiotechnology, Don State Technical University, Rostov-on-Don, Russia. .,Health Promoting Naturals Laboratory, School of Environmental and Biological Sciences, Rutgers State University, New Brunswick, NJ, USA. .,I.M. Sechenov First Moscow State Medical University, Moscow, Russia.
| |
Collapse
|
14
|
Castillo-Castañeda A, Cañas-Duarte SJ, Guevara-Suarez M, Guarro J, Restrepo S, Celis Ramírez AM. Transcriptional response of Fusarium oxysporum and Neocosmospora solani challenged with amphotericin B or posaconazole. MICROBIOLOGY (READING, ENGLAND) 2020; 166:936-946. [PMID: 32644917 PMCID: PMC7660915 DOI: 10.1099/mic.0.000927] [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] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Accepted: 04/27/2020] [Indexed: 01/09/2023]
Abstract
Some species of fusaria are well-known pathogens of humans, animals and plants. Fusarium oxysporum and Neocosmospora solani (formerly Fusarium solani) cause human infections that range from onychomycosis or keratitis to severe disseminated infections. In general, these infections are difficult to treat due to poor therapeutic responses in immunocompromised patients. Despite that, little is known about the molecular mechanisms and transcriptional changes responsible for the antifungal resistance in fusaria. To shed light on the transcriptional response to antifungals, we carried out the first reported high-throughput RNA-seq analysis for F. oxysporum and N. solani that had been exposed to amphotericin B (AMB) and posaconazole (PSC). We detected significant differences between the transcriptional profiles of the two species and we found that some oxidation-reduction, metabolic, cellular and transport processes were regulated differentially by both fungi. The same was found with several genes from the ergosterol synthesis, efflux pumps, oxidative stress response and membrane biosynthesis pathways. A significant up-regulation of the C-22 sterol desaturase (ERG5), the sterol 24-C-methyltransferase (ERG6) gene, the glutathione S-transferase (GST) gene and of several members of the major facilitator superfamily (MSF) was demonstrated in this study after treating F. oxysporum with AMB. These results offer a good overview of transcriptional changes after exposure to commonly used antifungals, highlights the genes that are related to resistance mechanisms of these fungi, which will be a valuable tool for identifying causes of failure of treatments.
Collapse
Affiliation(s)
- A. Castillo-Castañeda
- Grupo de Investigación Celular y Molecular de Microorganismos Patógenos (CeMoP), Departamento de Ciencias Biológicas, Universidad de Los Andes, Bogotá, Colombia
- Laboratorio de Micología y Fitopatología (LAMFU), Facultad de Ingeniería, Universidad de Los Andes, Bogotá, Colombia
| | - S. J. Cañas-Duarte
- Department of Systems Biology, Blavatnik Institute at Harvard Medical School, Harvard University, Boston, MA, USA
| | - M. Guevara-Suarez
- Grupo de Investigación Celular y Molecular de Microorganismos Patógenos (CeMoP), Departamento de Ciencias Biológicas, Universidad de Los Andes, Bogotá, Colombia
- Laboratorio de Micología y Fitopatología (LAMFU), Facultad de Ingeniería, Universidad de Los Andes, Bogotá, Colombia
| | - J. Guarro
- Facultat de Medicina I Ciéncies de la Salut, Departament de Ciéncies Médiques Básiques, Unitat de Microbiología. Universitat de Rovira I Virgili, Reus, España
| | - S. Restrepo
- Laboratorio de Micología y Fitopatología (LAMFU), Facultad de Ingeniería, Universidad de Los Andes, Bogotá, Colombia
| | - A. M. Celis Ramírez
- Grupo de Investigación Celular y Molecular de Microorganismos Patógenos (CeMoP), Departamento de Ciencias Biológicas, Universidad de Los Andes, Bogotá, Colombia
| |
Collapse
|
15
|
Oliveira FFM, Paes HC, Peconick LDF, Fonseca FL, Marina CLF, Bocca AL, Homem-de-Mello M, Rodrigues ML, Albuquerque P, Nicola AM, Alspaugh JA, Felipe MSS, Fernandes L. Erg6 affects membrane composition and virulence of the human fungal pathogen Cryptococcus neoformans. Fungal Genet Biol 2020; 140:103368. [PMID: 32201128 DOI: 10.1016/j.fgb.2020.103368] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 02/12/2020] [Accepted: 02/17/2020] [Indexed: 12/12/2022]
Abstract
Ergosterol is the most important membrane sterol in fungal cells and a component not found in the membranes of human cells. We identified the ERG6 gene in the AIDS-associated fungal pathogen, Cryptococcus neoformans, encoding the sterol C-24 methyltransferase of fungal ergosterol biosynthesis. In this work, we have explored its relationship with high-temperature growth and virulence of C. neoformans by the construction of a loss-of-function mutant. In contrast to other genes involved in ergosterol biosynthesis, C. neoformans ERG6 is not essential for growth under permissive conditions in vitro. However, the erg6 mutant displayed impaired thermotolerance and increased susceptibility to osmotic and oxidative stress, as well as to different antifungal drugs. Total lipid analysis demonstrated a decrease in the erg6Δ strain membrane ergosterol content. In addition, this mutant strain was avirulent in an invertebrate model of C. neoformans infection. C. neoformans Erg6 was cyto-localized in the endoplasmic reticulum and Golgi complex. Our results demonstrate that Erg6 is crucial for growth at high temperature and virulence, likely due to its effects on C. neoformans membrane integrity and dynamics. These pathogen-focused investigations into ergosterol biosynthetic pathway components reinforce the multiple roles of ergosterol in the response of diverse fungal species to alterations in the environment, especially that of the infected host. These studies open perspectives to understand the participation of ergosterol in mechanism of resistance to azole and polyene drugs. Observed synergistic growth defects with co-inhibition of Erg6 and other components of the ergosterol biosynthesis pathway suggests novel approaches to treatment in human fungal infections.
Collapse
Affiliation(s)
- Fabiana Freire M Oliveira
- Faculty of Medicine, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasília, Federal District 70910-900, Brazil
| | - Hugo Costa Paes
- Faculty of Medicine, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasília, Federal District 70910-900, Brazil
| | - Luísa Defranco F Peconick
- Faculty of Ceilândia, Campus UnB Ceilândia, University of Brasília, Ceilândia Sul, Centro Metropolitano, Brasília, Federal District 72220-275, Brazil
| | - Fernanda L Fonseca
- Center for Technological Development in Health (CDTS), Fiocruz-RJ, Rio de Janeiro 21045-360, Brazil.
| | - Clara Luna Freitas Marina
- Laboratory of Applied Immunology, Institute of Biology, Room J1 28/8, Building J, 2nd Floor, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasilia, Federal District 70910-900, Brazil
| | - Anamélia Lorenzetti Bocca
- Laboratory of Applied Immunology, Institute of Biology, Room J1 28/8, Building J, 2nd Floor, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasilia, Federal District 70910-900, Brazil.
| | - Mauricio Homem-de-Mello
- Faculty of Health Science, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasília, Federal District 70910-900, Brazil.
| | - Márcio Lourenço Rodrigues
- Carlos Chagas Institute, Fiocruz-PR, Curitiba 81310-020, Brazil; Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro 21941-590, Brazil
| | - Patrícia Albuquerque
- Faculty of Ceilândia, Campus UnB Ceilândia, University of Brasília, Ceilândia Sul, Centro Metropolitano, Brasília, Federal District 72220-275, Brazil
| | - André Moraes Nicola
- Faculty of Medicine, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasília, Federal District 70910-900, Brazil
| | - J Andrew Alspaugh
- Duke University School of Medicine, Dept. of Medicine, Durham, DUMC Box 102359, 303 Sands Building, Research Drive, Durham, NC 27710, USA.
| | - Maria Sueli S Felipe
- Catolic University of Brasilia, Campus Asa Norte, SGAN 916 Módulo B Avenida W5, Asa Norte, Brasília, Federal District 70790-160, Brazil
| | - Larissa Fernandes
- Faculty of Ceilândia, Campus UnB Ceilândia, University of Brasília, Ceilândia Sul, Centro Metropolitano, Brasília, Federal District 72220-275, Brazil; Laboratory of Applied Immunology, Institute of Biology, Room J1 28/8, Building J, 2nd Floor, Campus Darcy Ribeiro, University of Brasília, Asa Norte, Brasilia, Federal District 70910-900, Brazil.
| |
Collapse
|
16
|
Khan Z, Ahmad S, Al-Sweih N, Mokaddas E, Al-Banwan K, Alfouzan W, Al-Obaid I, Al-Obaid K, Varghese S. Increasing Trends of Reduced Susceptibility to Antifungal Drugs Among Clinical Candida glabrata Isolates in Kuwait. Microb Drug Resist 2020; 26:982-990. [PMID: 32101082 DOI: 10.1089/mdr.2019.0437] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Among non-albicans Candida species, Candida glabrata is the leading cause of invasive infections in critically ill patients. It is intrinsically less susceptible to fluconazole/other azoles that limits therapeutic options. This study determined distribution of C. glabrata in clinical specimens and determined their susceptibility to fluconazole, caspofungin, and amphotericin B by E test. During 8-year period (2011-2018), 1,410 isolates were obtained from 1,410 patients including 600, 409, and 131 isolates from respiratory, urine, and bloodstream specimens, respectively. Proportion of C. glabrata isolates was nearly the same during the two 4-year periods. Demographic details were available from 731 patients and susceptibility data for 1,225 isolates. C. glabrata isolation from bloodstream, respiratory, and urine specimens was higher from elderly (>60 years) versus younger patients. More bloodstream and urine isolates were obtained from female patients, however, more respiratory isolates were recovered from male patients (p = <0.05). Resistance to all three drugs increased during 2015-2018 compared with 2011-2014 but was more pronounced for fluconazole (p = 0.001). More isolates with reduced susceptibility to fluconazole/amphotericin B were obtained from elderly patients versus younger subjects and urine versus respiratory samples (p = <0.05). Our data show increasing trends of reduced susceptibility to antifungals, particularly fluconazole, among clinical C. glabrata isolates in Kuwait. Most isolates with reduced susceptibility to fluconazole/amphotericin B were obtained from elderly patients and urine/respiratory samples with urinary tract appearing as the most favorable niche for antifungal drug resistance development. The study also highlights the need for continued surveillance and better antifungal drug stewardship to control resistance development in C. glabrata.
Collapse
Affiliation(s)
- Ziauddin Khan
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait
| | - Suhail Ahmad
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait
| | - Noura Al-Sweih
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait
| | - Eiman Mokaddas
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait
| | - Khalifa Al-Banwan
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait
| | - Wadha Alfouzan
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait
| | - Inaam Al-Obaid
- Department of Microbiology, Al-Sabah Hospital, Shuwaikh, Kuwait
| | - Khaled Al-Obaid
- Department of Microbiology, Mubarak Al-Kabir Hospital, Jabriya, Kuwait
| | - Soumya Varghese
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait
| |
Collapse
|
17
|
Salazar SB, Simões RS, Pedro NA, Pinheiro MJ, Carvalho MFNN, Mira NP. An Overview on Conventional and Non-Conventional Therapeutic Approaches for the Treatment of Candidiasis and Underlying Resistance Mechanisms in Clinical Strains. J Fungi (Basel) 2020; 6:E23. [PMID: 32050673 PMCID: PMC7151124 DOI: 10.3390/jof6010023] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/06/2020] [Accepted: 02/07/2020] [Indexed: 02/06/2023] Open
Abstract
Fungal infections and, in particular, those caused by species of the Candida genus, are growing at an alarming rate and have high associated rates of mortality and morbidity. These infections, generally referred as candidiasis, range from common superficial rushes caused by an overgrowth of the yeasts in mucosal surfaces to life-threatening disseminated mycoses. The success of currently used antifungal drugs to treat candidiasis is being endangered by the continuous emergence of resistant strains, specially among non-albicans Candida species. In this review article, the mechanisms of action of currently used antifungals, with emphasis on the mechanisms of resistance reported in clinical isolates, are reviewed. Novel approaches being taken to successfully inhibit growth of pathogenic Candida species, in particular those based on the exploration of natural or synthetic chemicals or on the activity of live probiotics, are also reviewed. It is expected that these novel approaches, either used alone or in combination with traditional antifungals, may contribute to foster the identification of novel anti-Candida therapies.
Collapse
Affiliation(s)
- Sara B. Salazar
- Department of Bioengineering, Institute of Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal; (S.B.S.); (R.S.S.); (N.A.P.); (M.J.P.)
| | - Rita S. Simões
- Department of Bioengineering, Institute of Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal; (S.B.S.); (R.S.S.); (N.A.P.); (M.J.P.)
| | - Nuno A. Pedro
- Department of Bioengineering, Institute of Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal; (S.B.S.); (R.S.S.); (N.A.P.); (M.J.P.)
| | - Maria Joana Pinheiro
- Department of Bioengineering, Institute of Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal; (S.B.S.); (R.S.S.); (N.A.P.); (M.J.P.)
| | - Maria Fernanda N. N. Carvalho
- Centro de Química Estrutural, Complexo I, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal;
| | - Nuno P. Mira
- Department of Bioengineering, Institute of Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal; (S.B.S.); (R.S.S.); (N.A.P.); (M.J.P.)
| |
Collapse
|
18
|
Tian Y, Gao N, Ni Q, Mao Y, Dong D, Huang X, Jiang C, Li Z, Zhang L, Wang X, Peng Y, Chen C. Sequence modification of the master regulator Pdr1 interferes with its transcriptional autoregulation and confers altered azole resistance in Candida glabrata. FEMS Yeast Res 2019; 18:4966987. [PMID: 29648590 DOI: 10.1093/femsyr/foy038] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 04/09/2018] [Indexed: 01/09/2023] Open
Abstract
The transcriptional regulator Pdr1 plays a positive role in regulating azole drug resistance in Candida glabrata. Previous studies have shown the importance of the carboxyl (C)-terminal sequence of Pdr1 in fulfilling its function, as this region mediates interactions between Pdr1 and the co-activator Gal11A and is crucial for activation of Pdr1 targets. However, mechanisms of how Pdr1 is regulated, especially implication of its C-terminus in the regulatory activity, remain uncharacterized. In this study, we unexpectedly observed that the C-terminal modification of Pdr1 in an azole-resistant clinical isolate harboring a single GOF mutation, resulted in adverse effects such as decreased expression levels of Pdr1, downregulation of Pdr1 targets and azole hypersensitivity. Importantly, the C-terminal 3 × FLAG tagging significantly decreased the binding of Pdr1 to the pleiotropic drug response elements in its own promoter, promoted an irregular cellular mislocalization and thereby disrupted the transcriptional autoregulation of this master regulator. Unexpectedly, the aberrant cytoplasmic localization caused a non-functional interaction with Gal11A, a co-activator involved in drug resistance. Based on these findings, we proposed that C-terminal sequence of Pdr1 is vital for its stability and functionality, and targeting regulation of this region may represent a promising future strategy for combating C. glabrata infection and drug resistance.
Collapse
Affiliation(s)
- Yuan Tian
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No. 197 Ruijin ER Road, Shanghai 200025, China
| | - Ning Gao
- Unit of Pathogenic Fungal Infection and Host Immunity, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200031, China
| | - Qi Ni
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No. 197 Ruijin ER Road, Shanghai 200025, China
| | - Yinhe Mao
- Unit of Pathogenic Fungal Infection and Host Immunity, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200031, China
| | - Danfeng Dong
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No. 197 Ruijin ER Road, Shanghai 200025, China
| | - Xinhua Huang
- Unit of Pathogenic Fungal Infection and Host Immunity, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200031, China
| | - Cen Jiang
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No. 197 Ruijin ER Road, Shanghai 200025, China
| | - Zhen Li
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No. 197 Ruijin ER Road, Shanghai 200025, China
| | - Lihua Zhang
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No. 197 Ruijin ER Road, Shanghai 200025, China
| | - Xuefeng Wang
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No. 197 Ruijin ER Road, Shanghai 200025, China
| | - Yibing Peng
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, No. 197 Ruijin ER Road, Shanghai 200025, China
| | - Changbin Chen
- Unit of Pathogenic Fungal Infection and Host Immunity, Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200031, China
| |
Collapse
|
19
|
Sharma J, Rosiana S, Razzaq I, Shapiro RS. Linking Cellular Morphogenesis with Antifungal Treatment and Susceptibility in Candida Pathogens. J Fungi (Basel) 2019; 5:E17. [PMID: 30795580 PMCID: PMC6463059 DOI: 10.3390/jof5010017] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 02/11/2019] [Accepted: 02/13/2019] [Indexed: 02/07/2023] Open
Abstract
Fungal infections are a growing public health concern, and an increasingly important cause of human mortality, with Candida species being amongst the most frequently encountered of these opportunistic fungal pathogens. Several Candida species are polymorphic, and able to transition between distinct morphological states, including yeast, hyphal, and pseudohyphal forms. While not all Candida pathogens are polymorphic, the ability to undergo morphogenesis is linked with the virulence of many of these pathogens. There are also many connections between Candida morphogenesis and antifungal drug treatment and susceptibility. Here, we review how Candida morphogenesis-a key virulence trait-is linked with antifungal drugs and antifungal drug resistance. We highlight how antifungal therapeutics are able to modulate morphogenesis in both sensitive and drug-resistant Candida strains, the shared signaling pathways that mediate both morphogenesis and the cellular response to antifungal drugs and drug resistance, and the connection between Candida morphology, drug resistance, and biofilm growth. We further review the development of anti-virulence drugs, and targeting Candida morphogenesis as a novel therapeutic strategy to target fungal pathogens. Together, this review highlights important connections between fungal morphogenesis, virulence, and susceptibility to antifungals.
Collapse
Affiliation(s)
- Jehoshua Sharma
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada.
| | - Sierra Rosiana
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada.
| | - Iqra Razzaq
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada.
| | - Rebecca S Shapiro
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada.
| |
Collapse
|
20
|
Candida glabrata: A Lot More Than Meets the Eye. Microorganisms 2019; 7:microorganisms7020039. [PMID: 30704135 PMCID: PMC6407134 DOI: 10.3390/microorganisms7020039] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/21/2019] [Accepted: 01/29/2019] [Indexed: 01/17/2023] Open
Abstract
Candida glabrata is an opportunistic human fungal pathogen that causes superficial mucosal and life-threatening bloodstream infections in individuals with a compromised immune system. Evolutionarily, it is closer to the non-pathogenic yeast Saccharomyces cerevisiae than to the most prevalent Candida bloodstream pathogen, C. albicans. C. glabrata is a haploid budding yeast that predominantly reproduces clonally. In this review, we summarize interactions of C. glabrata with the host immune, epithelial and endothelial cells, and the ingenious strategies it deploys to acquire iron and phosphate from the external environment. We outline various attributes including cell surface-associated adhesins and aspartyl proteases, biofilm formation and stress response mechanisms, that contribute to the virulence of C. glabrata. We further discuss how, C. glabrata, despite lacking morphological switching and secreted proteolytic activity, is able to disarm macrophage, dampen the host inflammatory immune response and replicate intracellularly.
Collapse
|
21
|
ERG6 and ERG2 Are Major Targets Conferring Reduced Susceptibility to Amphotericin B in Clinical Candida glabrata Isolates in Kuwait. Antimicrob Agents Chemother 2019; 63:AAC.01900-18. [PMID: 30455247 DOI: 10.1128/aac.01900-18] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 11/12/2018] [Indexed: 12/21/2022] Open
Abstract
Candida glabrata is intrinsically less susceptible to azoles, and resistance to echinocandins and reduced susceptibility (RS) to amphotericin B (AMB) have also been detected. The molecular mechanisms of RS to AMB were investigated in C. glabrata strains in Kuwait by sequence analyses of genes involved in ergosterol biosynthesis. A total of 1,646 C. glabrata isolates were tested by Etest, and results for 12 selected isolates were confirmed by reference broth microdilution. PCR sequencing of three genes (ERG2, ERG6, and ERG11) was performed for all isolates with RS to AMB (RS-AMB isolates) and 5 selected wild-type C. glabrata isolates by using gene-specific primers. The total cell sterol content was analyzed by gas chromatography-mass spectrometry. The phylogenetic relationship among the isolates was investigated by multilocus sequence typing. Wild-type isolates contained only synonymous mutations in ERG2, ERG6, or ERG11, and the total sterol content was similar to that of the reference strains. A nonsynonymous ERG6 mutation (AGA48AAA, R48K) was found in both RS-AMB and wild-type isolates. Four RS-AMB isolates contained novel nonsense mutations at Trp286, Tyr192, and Leu341, and 2 isolates contained a nonsynonymous mutation in ERG6 (V126F or C198F); and the sterol content of these isolates was consistent with ERG6 deficiency. Two other RS-AMB isolates contained a novel nonsynonymous ERG2 mutation (G119S or G122S), and their sterol content was consistent with ERG2 deficiency. Of 8 RS-AMB isolates, 1 fluconazole-resistant isolate also contained nonsynonymous Y141H plus L381M mutations, while 7 isolates contained only synonymous mutations in ERG11 All isolates with ERG6, ERG2, and ERG11 mutations were genotypically distinct strains. Our data show that ERG6 and ERG2 are major targets conferring RS-AMB in clinical C. glabrata isolates.
Collapse
|
22
|
Pais P, Galocha M, Teixeira MC. Genome-Wide Response to Drugs and Stress in the Pathogenic Yeast Candida glabrata. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2019; 58:155-193. [PMID: 30911893 DOI: 10.1007/978-3-030-13035-0_7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Candida glabrata is the second most common cause of candidemia worldwide and its prevalence has continuously increased over the last decades. C. glabrata infections are especially worrisome in immunocompromised patients, resulting in serious systemic infections, associated to high mortality rates. Intrinsic resistance to azole antifungals, widely used drugs in the clinical setting, and the ability to efficiently colonize the human host and medical devices, withstanding stress imposed by the immune system, are thought to underlie the emergence of C. glabrata. There is a clear clinical need to understand drug and stress resistance in C. glabrata. The increasing prevalence of multidrug resistant isolates needs to be addressed in order to overcome the decrease of viable therapeutic strategies and find new therapeutic targets. Likewise, the understanding of the mechanisms underlying its impressive ability thrive under oxidative, nitrosative, acidic and metabolic stresses, is crucial to design drugs that target these pathogenesis features. The study of the underlying mechanisms that translate C. glabrata plasticity and its competence to evade the immune system, as well as survive host stresses to establish infection, will benefit from extensive scrutiny. This chapter provides a review on the contribution of genome-wide studies to uncover clinically relevant drug resistance and stress response mechanisms in the human pathogenic yeast C. glabrata.
Collapse
Affiliation(s)
- Pedro Pais
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.,Biological Sciences Research Group, Institute for Bioengineering and Biosciences (iBB), Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Mónica Galocha
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.,Biological Sciences Research Group, Institute for Bioengineering and Biosciences (iBB), Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
| | - Miguel Cacho Teixeira
- Department of Bioengineering, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal. .,Biological Sciences Research Group, Institute for Bioengineering and Biosciences (iBB), Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
| |
Collapse
|
23
|
Combination of Posaconazole and Amphotericin B in the Treatment of Candida glabrata Biofilms. Microorganisms 2018; 6:microorganisms6040123. [PMID: 30518069 PMCID: PMC6313645 DOI: 10.3390/microorganisms6040123] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 11/27/2018] [Accepted: 11/29/2018] [Indexed: 12/17/2022] Open
Abstract
Candidemia cases have been increasing, especially among immunosuppressed patients. Candida glabrata is one of the most resistant Candida species, especially to the azole drugs, resulting in a high demand for therapeutic alternatives. The minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), and minimum biofilm eradication concentration (MBEC) were determined for posaconazole (Pcz) and amphotericin B (AmB). The drug combinations of both drugs were evaluated on pre-formed biofilms of C. glabrata ATCC 2001, through XTT (2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) assay, colony forming units (CFU), crystal violet, and the fractional inhibitory concentration index (FICI). C. glabrata revealed higher susceptibility and biofilm reduction in the presence of AmB alone, but both drugs revealed a good capacity in the biomass elimination. In the majority of the tested combinations, the interactions were defined as indifferent (FICI ≤ 4). The combination of the two drugs does not seem to bring a clear advantage in the treatment of biofilms of C. glabrata.
Collapse
|
24
|
Ko JH, Jung DS, Lee JY, Kim HA, Ryu SY, Jung SI, Joo EJ, Cheon S, Kim YS, Kim SW, Cho SY, Kang CI, Chung DR, Lee NY, Peck KR. Changing epidemiology of non-albicans candidemia in Korea. J Infect Chemother 2018; 25:388-391. [PMID: 30482698 DOI: 10.1016/j.jiac.2018.09.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 08/28/2018] [Accepted: 09/30/2018] [Indexed: 10/28/2022]
Abstract
An epidemiologic surveillance of non-albicans candidemia for a 6-year period was conducted in Korea. Compared to the published epidemiologic data for the previous 6 years, an increase of C. glabrata (from 21.3% to 28.5%) and a decrease of C. parapsilosis (from 36.5% to 24.7%) were noticed. During the study period, C. tropicalis (36.4%) was most frequently isolated non-albicans Candida, followed by C. glabrata (28.5%), C. parapsilosis (24.7%), and C. krusei (2.6%). Replacement of primary amphotericin B treatment with echinocandins (P < 0.001) eliminated amphotericin B resistance (from 7.8% in 2011 to 0% in 2014).
Collapse
Affiliation(s)
- Jae-Hoon Ko
- Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Dong Sik Jung
- Division of Infectious Diseases, Dong-A University College of Medicine, Busan, Republic of Korea
| | - Ji Yeon Lee
- Division of Infectious Diseases, Keimyung University Dongsan Medical Center, Daegu, Republic of Korea
| | - Hyun Ah Kim
- Division of Infectious Diseases, Keimyung University Dongsan Medical Center, Daegu, Republic of Korea
| | - Seong Yeol Ryu
- Division of Infectious Diseases, Keimyung University Dongsan Medical Center, Daegu, Republic of Korea
| | - Sook-In Jung
- Division of Infectious Diseases, Chonnam National University Hospital, Gwangju, Republic of Korea
| | - Eun-Jeong Joo
- Division of Infectious Diseases, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Shinhye Cheon
- Division of Infectious Diseases, Chungnam National University School of Medicine, Daejeon, Republic of Korea
| | - Yeon-Sook Kim
- Division of Infectious Diseases, Chungnam National University School of Medicine, Daejeon, Republic of Korea
| | - Shin-Woo Kim
- Division of Infectious Diseases, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Sun Young Cho
- Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Cheol-In Kang
- Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Doo Ryeon Chung
- Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Nam Yong Lee
- Department of Laboratory Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Kyong Ran Peck
- Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
| |
Collapse
|
25
|
Abstract
PURPOSE OF REVIEW To describe the epidemiology, strategies for early detection, and clinical management of infections caused by the most commonly found multidrug-resistant (MDR) Candida spp. RECENT FINDINGS Increasing numbers of reports describing invasive infections by MDR Candida auris and Candida glabrata has been reported in medical centers worldwide. SUMMARY We checked all papers published along the last 10 years describing epidemiological, diagnostic, and clinical aspects of infections by MDR Candida spp., with emphasis on C. auris and C. glabrata spp. C. auris has been reported in 15 countries and multidrug resistance rates is usually above 30%. Horizontal transmission is a great concern regarding C. auris. C. glabrata ranks the second most reported Candida spp. in deep-seated infections from United States and some European Centers, although multidrug resistance rates above 10% are restricted to some US centers. Candida haemulonii complex isolates with poor susceptibility to azoles and amphotericin B have been isolated in superficial and deep-seated infections, whereas Candida guilliiermondii complex isolates with poor susceptibility to azoles and echinocandins have been recovered from catheter-related bloodstream infections. Other potential MDR Candida species are Candida krusei, Candida lusitaniae, Candida kefyr, Yarrowia (Candida) lypolitica, and Candida rugosa.
Collapse
|
26
|
Geddes-McAlister J, Shapiro RS. New pathogens, new tricks: emerging, drug-resistant fungal pathogens and future prospects for antifungal therapeutics. Ann N Y Acad Sci 2018; 1435:57-78. [DOI: 10.1111/nyas.13739] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 03/19/2018] [Accepted: 03/28/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Jennifer Geddes-McAlister
- Department of Molecular and Cellular Biology; University of Guelph; Guelph Ontario Canada
- Department of Proteomics and Signal Transduction; Max Planck Institute of Biochemistry; Munich Germany
| | - Rebecca S. Shapiro
- Department of Molecular and Cellular Biology; University of Guelph; Guelph Ontario Canada
| |
Collapse
|
27
|
Targeting Candida spp. to develop antifungal agents. Drug Discov Today 2018; 23:802-814. [PMID: 29353694 DOI: 10.1016/j.drudis.2018.01.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 12/09/2017] [Accepted: 01/04/2018] [Indexed: 01/15/2023]
Abstract
Invasive fungal infections are a complex challenge throughout the world because of their high incidence, mainly in critically ill patients, and high mortality rates. The antifungal agents currently available are limited; thus, there is a need for the rapid development of new drugs. In silico methods are a modern strategy to explore interactions between new compounds and specific fungal targets, but they depend on precise genetic information. Here, we discuss the main Candida spp. target genes, including information about null mutants, virulence, cytolocalization, co-regulatory genes, and compounds that are related to protein expression. These data will provide a basis for the future in silico development of antifungal drugs.
Collapse
|
28
|
Liposomal and Deoxycholate Amphotericin B Formulations: Effectiveness against Biofilm Infections of Candida spp. Pathogens 2017; 6:pathogens6040062. [PMID: 29194382 PMCID: PMC5750586 DOI: 10.3390/pathogens6040062] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 11/20/2017] [Accepted: 11/29/2017] [Indexed: 11/29/2022] Open
Abstract
Background: candidiasis is the primary fungal infection encountered in patients undergoing prolonged hospitalization, and the fourth leading cause of nosocomial bloodstream infections. One of the most important Candida spp. virulence factors is the ability to form biofilms, which are extremely refractory to antimicrobial therapy and very difficult to treat with the traditional antifungal therapies. It is known that the prophylaxis or treatment of a systemic candidiasis are recurrently taken without considering the possibility of a Candida spp. biofilm-related infections. Therefore, it is important to assess the effectiveness of the available drugs and which formulations have the best performance in these specific infections. Methods: 24-h-biofilms of four Candida spp. and their response to two amphotericin B (AmB) pharmaceutical formulations (liposomal and deoxycholate) were evaluated. Results: generally, Candida glabrata was the less susceptible yeast species to both AmBs. MBECs revealed that it is therapeutically more appealing to use AmB-L than AmB-Deox for all Candida spp. biofilms, since none of the determined concentrations of AmB-L reached 10% of the maximum daily dose, but both formulations showed a very good capacity in the biomass reduction. Conclusions: the liposomal formulation presents better performance in the eradication of the biofilm cells for all the species in comparison with the deoxycholate formulation.
Collapse
|
29
|
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
|
30
|
Lotfali E, Ghajari A, Kordbacheh P, Zaini F, Mirhendi H, Mohammadi R, Noorbakhsh F, Rezaie S. Regulation of ERG3, ERG6, and ERG11 Genes in Antifungal-Resistant isolates of Candida parapsilosis. IRANIAN BIOMEDICAL JOURNAL 2017; 21:275-81. [PMID: 28176517 PMCID: PMC5459943 DOI: 10.18869/acadpub.ibj.21.4.275] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Background Candida parapsilosis is one of the five common strains of yeasts involved in invasive candidiasis. The expression analysis of sterol biosynthesis pathway genes, which are associated with resistance, can assist the better understanding of antifungal resistance mechanisms. Method The antifungal susceptibility of 120 clinical C. parapsilosis isolates was examined. The changes in the gene expression related to resistance were analyzed. Results Eight strains were resistant to fluconazole (FLC), itraconazole (ITC), and amphotericin B (AMB). The regulation variations included increased mRNA levels of ERG3, ERG6, and ERG11 and decreased mRNA levels of ERG3 and ERG6 in response to FLC. ERG11 mRNA level increases in response to ITC and AMB. Conclusion The mechanism of resistance to azoles in C. parapsilosis is very similar to C. Albicans. This feature may help to design new treatment strategy for candidiasis.
Collapse
Affiliation(s)
- Ensieh Lotfali
- Department of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ali Ghajari
- Department of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Parivash Kordbacheh
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Farideh Zaini
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Hossein Mirhendi
- Department of Medical Parasitology and Mycology, School of Medicine, Infectious Disease and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Rasoul Mohammadi
- Department of Medical Parasitology and Mycology, School of Medicine, Infectious Disease and Tropical Medicine Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Fatemeh Noorbakhsh
- Department of Biology, Faculty of Science, Islamic Azad University, Varamin-Pishva, Iran
| | - Sassan Rezaie
- Division of Molecular Biology, Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
31
|
Resistance to antifungal therapies. Essays Biochem 2017; 61:157-166. [DOI: 10.1042/ebc20160067] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/02/2017] [Accepted: 01/05/2017] [Indexed: 11/17/2022]
Abstract
The evolution of antifungal resistance among fungal pathogens has rendered the limited arsenal of antifungal drugs futile. Considering the recent rise in the number of nosocomial fungal infections in immunocompromised patients, the emerging clinical multidrug resistance (MDR) has become a matter of grave concern for medical professionals. Despite advances in therapeutic interventions, it has not yet been possible to devise convincing strategies to combat antifungal resistance. Comprehensive understanding of the molecular mechanisms of antifungal resistance is essential for identification of novel targets that do not promote or delay emergence of drug resistance. The present study discusses features and limitations of the currently available antifungals, mechanisms of antifungal resistance and highlights the emerging therapeutic strategies that could be deployed to combat MDR.
Collapse
|
32
|
Rodrigues CF, Rodrigues ME, Silva S, Henriques M. Candida glabrata Biofilms: How Far Have We Come? J Fungi (Basel) 2017; 3:E11. [PMID: 29371530 PMCID: PMC5715960 DOI: 10.3390/jof3010011] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 02/07/2017] [Accepted: 02/16/2017] [Indexed: 11/25/2022] Open
Abstract
Infections caused by Candida species have been increasing in the last decades and can result in local or systemic infections, with high morbidity and mortality. After Candida albicans, Candida glabrata is one of the most prevalent pathogenic fungi in humans. In addition to the high antifungal drugs resistance and inability to form hyphae or secret hydrolases, C. glabrata retain many virulence factors that contribute to its extreme aggressiveness and result in a low therapeutic response and serious recurrent candidiasis, particularly biofilm formation ability. For their extraordinary organization, especially regarding the complex structure of the matrix, biofilms are very resistant to antifungal treatments. Thus, new approaches to the treatment of C. glabrata's biofilms are emerging. In this article, the knowledge available on C. glabrata's resistance will be highlighted, with a special focus on biofilms, as well as new therapeutic alternatives to control them.
Collapse
Affiliation(s)
- Célia F Rodrigues
- CEB, Centre of Biological Engineering, LIBRO-Laboratório de Investigação em Biofilmes Rosário Oliveira, University of Minho, 4710-057 Braga, Portugal.
| | - Maria Elisa Rodrigues
- CEB, Centre of Biological Engineering, LIBRO-Laboratório de Investigação em Biofilmes Rosário Oliveira, University of Minho, 4710-057 Braga, Portugal.
| | - Sónia Silva
- CEB, Centre of Biological Engineering, LIBRO-Laboratório de Investigação em Biofilmes Rosário Oliveira, University of Minho, 4710-057 Braga, Portugal.
| | - Mariana Henriques
- CEB, Centre of Biological Engineering, LIBRO-Laboratório de Investigação em Biofilmes Rosário Oliveira, University of Minho, 4710-057 Braga, Portugal.
| |
Collapse
|
33
|
Bandara HMHN, Matsubara VH, Samaranayake LP. Future therapies targeted towards eliminating Candida biofilms and associated infections. Expert Rev Anti Infect Ther 2016; 15:299-318. [PMID: 27927053 DOI: 10.1080/14787210.2017.1268530] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Candida species are common human commensals and cause either superficial or invasive opportunistic infections. The biofilm form of candida as opposed to its suspended, planktonic form, is predominantly associated with these infections. Alternative or adjunctive therapies are urgently needed to manage Candida infections as the currently available short arsenal of antifungal drugs has been compromised due to their systemic toxicity, cross-reactivity with other drugs, and above all, by the emergence of drug-resistant Candida species due to irrational drug use. Areas covered: Combination anti-Candida therapies, antifungal lock therapy, denture cleansers, and mouth rinses have all been proposed as alternatives for disrupting candidal biofilms on different substrates. Other suggested approaches for the management of candidiasis include the use of natural compounds, such as probiotics, plants extracts and oils, antifungal quorum sensing molecules, anti-Candida antibodies and vaccines, cytokine therapy, transfer of primed immune cells, photodynamic therapy, and nanoparticles. Expert commentary: The sparsity of currently available antifungals and the plethora of proposed anti-candidal therapies is a distinct indication of the urgent necessity to develop efficacious therapies for candidal infections. Alternative drug delivery approaches, such as probiotics, reviewed here is likely to be a reality in clinical settings in the not too distant future.
Collapse
Affiliation(s)
- H M H N Bandara
- a School of Dentistry , The University of Queensland , Herston , QLD , Australia
| | - V H Matsubara
- b School of Dentistry , University of São Paulo , São Paulo , SP , Brazil.,c Department of Microbiology, Institute of Biomedical Sciences , University of São Paulo , São Paulo , SP , Brazil
| | - L P Samaranayake
- a School of Dentistry , The University of Queensland , Herston , QLD , Australia.,d Faculty of Dentistry , University of Kuwait , Kuwait
| |
Collapse
|
34
|
Konecna A, Toth Hervay N, Valachovic M, Gbelska Y. ERG6 gene deletion modifies Kluyveromyces lactis susceptibility to various growth inhibitors. Yeast 2016; 33:621-632. [PMID: 27668979 DOI: 10.1002/yea.3212] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 09/13/2016] [Accepted: 09/21/2016] [Indexed: 11/09/2022] Open
Abstract
The ERG6 gene encodes an S-adenosylmethionine dependent sterol C-24 methyltransferase in the ergosterol biosynthetic pathway. In this work we report the results of functional analysis of the Kluyveromyces lactis ERG6 gene. We cloned the KlERG6 gene, which was able to complement the erg6Δ mutation in both K. lactis and Saccharomyces cerevisiae. The lack of ergosterol in the Klerg6 deletion mutant was accompanied by increased expression of genes encoding the last steps of the ergosterol biosynthesis pathway as well as the KlPDR5 gene encoding an ABC transporter. The Klerg6Δ mutation resulted in reduced cell susceptibility to amphotericin B, nystatin and pimaricin and increased susceptibility to azole antifungals, fluphenazine, terbinafine, brefeldin A and caffeine. The susceptibility phenotype was suppressed by the KlPDR16 gene encoding one of the phosphatidylinositol transfer proteins belonging to the Sec14 family. Decreased activity of KlPdr5p in Klerg6Δ mutant (measured as the ability to efflux rhodamine 6G) together with increased amount of KlPDR5 mRNA suggest that the zymosterol which accumulates in the Klerg6Δ mutant may not fully compensate for ergosterol in the membrane targeting of efflux pumps. These results point to the fact that defects in sterol transmethylation appear to cause a multitude of physiological effects in K. lactis cells. Copyright © 2016 John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Alexandra Konecna
- Comenius University in Bratislava, Faculty of Natural Sciences, Department of Microbiology and Virology, Bratislava, Slovak Republic
| | - Nora Toth Hervay
- Comenius University in Bratislava, Faculty of Natural Sciences, Department of Microbiology and Virology, Bratislava, Slovak Republic
| | - Martin Valachovic
- Slovak Academy of Sciences, Institute of Animal Biochemistry and Genetics, Ivanka pri Dunaji, Slovak Republic
| | - Yvetta Gbelska
- Comenius University in Bratislava, Faculty of Natural Sciences, Department of Microbiology and Virology, Bratislava, Slovak Republic
| |
Collapse
|
35
|
Chudzik B, Czernel G, Miaskowski A, Gagoś M. Amphotericin B-copper(II) complex shows improved therapeutic index in vitro. Eur J Pharm Sci 2016; 97:9-21. [PMID: 27816628 DOI: 10.1016/j.ejps.2016.10.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 10/28/2016] [Accepted: 10/31/2016] [Indexed: 10/20/2022]
Abstract
The AmB-Cu(II) complex has recently been reported as an antifungal agent with reduced aggregation of AmB in aqueous solutions, increased anti C. albicans activity and lower toxicity against human cells in vitro. In the present work, investigations of the activity of the AmB-Cu (II) complex against fungal pathogens with varying susceptibility, including C. albicans and C. parapsilosis strains and intrinsically resistant A. niger, and cytotoxicity in normal human dermal fibroblasts (NHDF) in vitro were performed. For better understanding of the mechanism of reduced cytotoxicity and increased fungicidal activity, the influence of the AmB-Cu (II) complex on membrane integrity and accumulation of cellular reactive oxygen species (ROS) and mitochondrial superoxide was compared with that of conventional AmB. In the sensitive C. albicans and C. parapsilosis strains, the AmB-Cu(II) complex showed higher fungicidal activity (the MIC value was 0.35-0.7μg/ml for the AmB-Cu (II) complex, and 0.45-0.9μg/ml for Fungizone) due to increased induction of oxidative damage with rapid inhibition of the ability to reduce tetrazolium dye (MTT). In the NHDF cell line, the CC50 value was 30.13±1.53μg/ml for the AmB-Cu(II) complex and 17.46±1.24μg/ml for (Fungizone), therefore, the therapeutic index (CC50/MIC90) determined in vitro was 86.09-43.04 for the AmB-Cu(II) complex and 38.80-19.40 for Fungizone. The lower cytotoxicity of the AmB-Cu(II) complex in human cells resulted from lower accumulation of cellular and mitochondrial reactive oxygen species. This phenomenon was probably caused by the induction of successful antioxidant defense of the cells. The mechanism of the reduced cytotoxicity of the AmB-Cu(II) complex needs further investigation, but the preliminary results are very promising.
Collapse
Affiliation(s)
- Barbara Chudzik
- Department of Cell Biology, Institute of Biology and Biochemistry, Maria Curie-Skłodowska University, 20-033 Lublin, Poland.
| | - Grzegorz Czernel
- Department of Biophysics, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland
| | - Arkadiusz Miaskowski
- Department of Applied Mathematics and Computer Science, University of Life Sciences, Akademicka 13, 20-950 Lublin, Poland
| | - Mariusz Gagoś
- Department of Cell Biology, Institute of Biology and Biochemistry, Maria Curie-Skłodowska University, 20-033 Lublin, Poland.
| |
Collapse
|
36
|
Cierech M, Kolenda A, Grudniak AM, Wojnarowicz J, Woźniak B, Gołaś M, Swoboda-Kopeć E, Łojkowski W, Mierzwińska-Nastalska E. Significance of polymethylmethacrylate (PMMA) modification by zinc oxide nanoparticles for fungal biofilm formation. Int J Pharm 2016; 510:323-35. [PMID: 27346417 DOI: 10.1016/j.ijpharm.2016.06.052] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 06/16/2016] [Accepted: 06/20/2016] [Indexed: 11/30/2022]
Abstract
The objective of this study was to obtain a material composite with antifungal properties for dentures to be used as an alternative protocol in denture stomatitis treatment and prevention. Denture stomatitis is still a clinical problem in patients particularly vulnerable to this disease. Composites of PMMA and doped ZnO-NPs (weight concentrations, 2.5%, 5%, 7.5%) and PMMA with sprayed solvothermal and hydrothermal ZnO-NPs were tested. The following investigations of newly formed biomaterials were undertaken: influence on Candida albicans solution, biofilm staining, XTT analysis and a quantitative analysis of adhered C. albicans. These studies evidenced the antifungal activity of both nanocomposites PMMA-ZnO-NPs and the efficacy of sputtering of zinc oxide nanoparticles on the PMMA. The study of the biofilm deposition on the surface showed that antifungal properties increase with increasing concentration of ZnO-NPs. The XTT assay in conjunction with testing the turbidity of solutions may indicate the mechanism by which ZnO-NPs exert their effect on the increased induction of antioxidative stress in microorganism cells. The denture base made of the aforesaid materials may play a preventive role in patients susceptible to fungal infections. Based on the results obtained a modified treatment of stomatitis Type II (Newton's classification) complicated by fungal infection was proposed.
Collapse
Affiliation(s)
- Mariusz Cierech
- Department of Prosthodontics, Medical University of Warsaw, Poland.
| | - Adam Kolenda
- Department of Prosthodontics, Medical University of Warsaw, Poland
| | - Anna M Grudniak
- Department of Bacterial Genetics, Institute of Microbiology, Faculty of Biology, University of Warsaw, Poland
| | - Jacek Wojnarowicz
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland
| | - Bartosz Woźniak
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland
| | - Marlena Gołaś
- Department of Medical Microbiology, Medical University of Warsaw, Poland
| | - Ewa Swoboda-Kopeć
- Department of Medical Microbiology, Medical University of Warsaw, Poland
| | - Witold Łojkowski
- Institute of High Pressure Physics, Polish Academy of Sciences, Warsaw, Poland
| | | |
Collapse
|
37
|
Fernandes T, Silva S, Henriques M. Effect of Voriconazole on Candida tropicalis Biofilms: Relation with ERG Genes Expression. Mycopathologia 2016; 181:643-51. [PMID: 27260519 DOI: 10.1007/s11046-016-0023-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 05/23/2016] [Indexed: 10/21/2022]
Abstract
Candida tropicalis has emerged as the third most prevalent fungal pathogens and its ability to form biofilms has been considered one of the most important virulence factors, since biofilms represent high tolerance to antifungal agents. However, the mechanisms of C. tropicalis biofilm resistance to antifungals remain poorly understood. Thus, the main aim of this work was to infer about the effect of voriconazole on the formation and control of C. tropicalis biofilms and disclose its relationship with ERG genes' expression. Planktonic cells tolerance of several C. tropicalis clinical isolates to voriconazole was determined through of antifungal susceptibility test, and the effect of this azole against C. tropicalis biofilm formation and pre-formed biofilms was evaluated by cultivable cells determination and total biomass quantification. ERG genes expression was analyzed by quantitative real-time polymerase chain reaction. This work showed that C. tropicalis resistance to voriconazole is strain dependent and that voriconazole was able to partially control biofilm formation, but was unable to eradicate C. tropicalis pre-formed biofilms. Moreover, C. tropicalis biofilms resistance to voriconazole seems to be associated with alterations of sterol content in the cell membrane, resulting in ERG genes overexpression. Voriconazole is unable to control C. tropicalis biofilms, and the overexpression of ERG genes is a possible mechanism of biofilm resistance.
Collapse
Affiliation(s)
- Tânia Fernandes
- Laboratório de Investigação em Biofilmes Rosário Oliveira (LIBRO), Centre of Biological Engineering (CEB), University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal
| | - Sónia Silva
- Laboratório de Investigação em Biofilmes Rosário Oliveira (LIBRO), Centre of Biological Engineering (CEB), University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.
| | - Mariana Henriques
- Laboratório de Investigação em Biofilmes Rosário Oliveira (LIBRO), Centre of Biological Engineering (CEB), University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal
| |
Collapse
|
38
|
Prevalent mutator genotype identified in fungal pathogen Candida glabrata promotes multi-drug resistance. Nat Commun 2016; 7:11128. [PMID: 27020939 PMCID: PMC5603725 DOI: 10.1038/ncomms11128] [Citation(s) in RCA: 185] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 02/17/2016] [Indexed: 12/20/2022] Open
Abstract
The fungal pathogen Candida glabrata has emerged as a major health threat since it readily acquires resistance to multiple drug classes, including triazoles and/or echinocandins. Thus far, cellular mechanisms promoting the emergence of resistance to multiple drug classes have not been described in this organism. Here we demonstrate that a mutator phenotype caused by a mismatch repair defect is prevalent in C. glabrata clinical isolates. Strains carrying alterations in mismatch repair gene MSH2 exhibit a higher propensity to breakthrough antifungal treatment in vitro and in mouse models of colonization, and are recovered at a high rate (55% of all C. glabrata recovered) from patients. This genetic mechanism promotes the acquisition of resistance to multiple antifungals, at least partially explaining the elevated rates of triazole and multi-drug resistance associated with C. glabrata. We anticipate that identifying MSH2 defects in infecting strains may influence the management of patients on antifungal drug therapy. The fungal pathogen Candida glabrata readily acquires resistance to multiple types of antifungal drugs. Here, Healey et al. show that C. glabrata clinical isolates often carry mutations in a gene involved in DNA mismatch repair, and this is associated with increased propensity to develop antifungal resistance.
Collapse
|
39
|
Cell Wall Changes in Amphotericin B-Resistant Strains from Candida tropicalis and Relationship with the Immune Responses Elicited by the Host. Antimicrob Agents Chemother 2016; 60:2326-35. [PMID: 26833156 DOI: 10.1128/aac.02681-15] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 01/26/2016] [Indexed: 11/20/2022] Open
Abstract
We have morphologically characterizedCandida tropicalisisolates resistant to amphotericin B (AmB). These isolates present an enlarged cell wall compared to isolates of regular susceptibility. This correlated with higher levels of β-1,3-glucan in the cell wall but not with detectable changes in chitin content. In line with this, AmB-resistant strains showed reduced susceptibility to Congo red. Moreover, mitogen-activated protein kinases (MAPKs) involved in cell integrity were already activated during regular growth in these strains. Finally, we investigated the response elicited by human blood cells and found that AmB-resistant strains induced a stronger proinflammatory response than susceptible strains. In agreement, AmB-resistant strains also induced stronger melanization ofGalleria mellonellalarvae, indicating that the effect of alterations of the cell wall on the immune response is conserved in different types of hosts. Our results suggest that resistance to AmB is associated with pleiotropic mechanisms that might have important consequences, not only for the efficacy of the treatment but also for the immune response elicited by the host.
Collapse
|
40
|
Silva DBDS, Rodrigues LMC, Almeida AAD, Oliveira KMPD, Grisolia AB. Novel point mutations in the ERG11 gene in clinical isolates of azole resistant Candida species. Mem Inst Oswaldo Cruz 2016; 111:192-9. [PMID: 26982177 PMCID: PMC4804502 DOI: 10.1590/0074-02760150400] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 02/15/2016] [Indexed: 11/22/2022] Open
Abstract
The azoles are the class of medications most commonly used to fight infections caused
by Candida sp. Typically, resistance can be attributed to mutations
in ERG11 gene (CYP51) which encodes the cytochrome P450
14α-demethylase, the primary target for the activity of azoles. The objective of this
study was to identify mutations in the coding region of theERG11
gene in clinical isolates of Candidaspecies known to be resistant to
azoles. We identified three new synonymous mutations in the ERG11
gene in the isolates of Candida glabrata (C108G, C423T and A1581G)
and two new nonsynonymous mutations in the isolates of Candida
krusei - A497C (Y166S) and G1570A (G524R). The functional consequence of
these nonsynonymous mutations was predicted using evolutionary conservation scores.
The G524R mutation did not have effect on 14α-demethylase functionality, while the
Y166S mutation was found to affect the enzyme. This observation suggests a possible
link between the mutation and dose-dependent sensitivity to voriconazole in the
clinical isolate of C. krusei. Although the presence of the Y166S in
phenotype of reduced azole sensitivity observed in isolate C.
kruseidemands investigation, it might contribute to the search of new
therapeutic agents against resistant Candida isolates.
Collapse
|
41
|
Gonçalves SS, Souza ACR, Chowdhary A, Meis JF, Colombo AL. Epidemiology and molecular mechanisms of antifungal resistance in CandidaandAspergillus. Mycoses 2016; 59:198-219. [DOI: 10.1111/myc.12469] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Revised: 12/14/2015] [Accepted: 12/18/2015] [Indexed: 12/15/2022]
Affiliation(s)
- Sarah Santos Gonçalves
- Laboratório Especial de Micologia, Disciplina de Infectologia, Escola Paulista de Medicina; Universidade Federal de São Paulo; São Paulo SP Brazil
| | - Ana Carolina Remondi Souza
- Laboratório Especial de Micologia, Disciplina de Infectologia, Escola Paulista de Medicina; Universidade Federal de São Paulo; São Paulo SP Brazil
| | - Anuradha Chowdhary
- Department of Medical Mycology; Vallabhbhai Patel Chest Institute; University of Delhi; Delhi India
| | - Jacques F. Meis
- Department of Medical Microbiology and Infectious Diseases; Canisius Wilhelmina Hospital; Nijmegen the Netherlands
- Department of Medical Microbiology; Radboud University Medical Centre; Nijmegen the Netherlands
| | - Arnaldo Lopes Colombo
- Laboratório Especial de Micologia, Disciplina de Infectologia, Escola Paulista de Medicina; Universidade Federal de São Paulo; São Paulo SP Brazil
| |
Collapse
|
42
|
Prasad R, Shah AH, Rawal MK. Antifungals: Mechanism of Action and Drug Resistance. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 892:327-349. [PMID: 26721281 DOI: 10.1007/978-3-319-25304-6_14] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
There are currently few antifungals in use which show efficacy against fungal diseases. These antifungals mostly target specific components of fungal plasma membrane or its biosynthetic pathways. However, more recent class of antifungals in use is echinocandins which target the fungal cell wall components. The availability of mostly fungistatic antifungals in clinical use, often led to the development of tolerance to these very drugs by the pathogenic fungal species. Thus, the development of clinical multidrug resistance (MDR) leads to higher tolerance to drugs and its emergence is helped by multiple mechanisms. MDR is indeed a multifactorial phenomenon wherein a resistant organism possesses several mechanisms which contribute to display reduced susceptibility to not only single drug in use but also show collateral resistance to several drugs. Considering the limited availability of antifungals in use and the emergence of MDR in fungal infections, there is a continuous need for the development of novel broad spectrum antifungal drugs with better efficacy. Here, we briefly present an overview of the current understanding of the antifungal drugs in use, their mechanism of action and the emerging possible novel antifungal drugs with great promise.
Collapse
Affiliation(s)
- Rajendra Prasad
- Membrane Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India. .,AMITY Institute of Integrative Sciences and Health (AIISH), Amity University Haryana, Manesar, Gurgaon, Haryana, India.
| | - Abdul Haseeb Shah
- Membrane Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Manpreet Kaur Rawal
- Membrane Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| |
Collapse
|
43
|
Tam P, Gee K, Piechocinski M, Macreadie I. Candida glabrata, Friend and Foe. J Fungi (Basel) 2015; 1:277-292. [PMID: 29376912 PMCID: PMC5753114 DOI: 10.3390/jof1020277] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 09/07/2015] [Accepted: 09/09/2015] [Indexed: 11/16/2022] Open
Abstract
Candida glabrata is mostly good, but, at times, it is an opportunistic pathogen. Previously known as Torulopsis glabrata, it enjoyed a good reputation and was even present in starter cultures. Its haploid genome and lack of mating made it an attractive challenge for yeast genetics studies. However, more recently it has become better known due to its character as an emerging cause of candidiasis, and for its resistance to multidrugs that are employed for candidiasis treatment. While now classified as Candida glabrata, it is still not a good fit and tends to stand alone as a very unique yeast. In terms of sequence, it is dissimilar to other Candida yeast and most similar to Saccharomyces cerevisiae.
Collapse
Affiliation(s)
- Phyllix Tam
- School of Applied Sciences, RMIT University, Bundoora, Victoria 3083, Australia.
| | - Kirsten Gee
- School of Applied Sciences, RMIT University, Bundoora, Victoria 3083, Australia.
| | - Miryam Piechocinski
- School of Applied Sciences, RMIT University, Bundoora, Victoria 3083, Australia.
| | - Ian Macreadie
- School of Applied Sciences, RMIT University, Bundoora, Victoria 3083, Australia.
| |
Collapse
|
44
|
Foglia F, Rogers SE, Webster JRP, Akeroyd FA, Gascoyne KF, Lawrence MJ, Barlow DJ. Neutron Scattering Studies of the Effects of Formulating Amphotericin B with Cholesteryl Sulfate on the Drug's Interactions with Phospholipid and Phospholipid-Sterol Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:8042-8051. [PMID: 26139630 DOI: 10.1021/acs.langmuir.5b01365] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Langmuir surface pressure, small-angle neutron scattering (SANS), and neutron reflectivity (NR) studies have been performed to determine how formulation of the antifungal drug amphotericin B (AmB), with sodium cholesteryl sulfate (SCS)-as in Amphotec-affects its interactions with ergosterol-containing (model fungal cell) and cholesterol-containing (model mammalian cell) membranes. The effects of mixing AmB in 1:1 molar ratio with cholesteryl sulfate (yielding AmB-SCS micelles) are compared against those of free AmB, using monolayers and bilayers formed from palmitoyloleoylphosphatidylcholine (POPC) in the absence and presence of 30 mol % ergosterol or cholesterol, in all cases employing a 1:0.05 molar ratio of lipid:AmB. Analyses of the (bilayer) SANS and (monolayer) NR data indicate that the equilibrium changes in membrane structure induced in sterol-free and sterol-containing membranes are the same for free AmB and AmB-SCS. Stopped-flow SANS experiments, however, reveal that the structural changes to vesicle membranes occur far more rapidly following exposure to AmB-SCS vs free drug, with the kinetics of these changes varying with membrane composition. With POPC vesicles, the structural changes induced by AmB-SCS become apparent only after several minutes, and equilibrium is reached after ∼30 min. The corresponding onset of changes in POPC-ergosterol and POPC-cholesterol vesicles, however, occurs within ∼5 s, with equilibrium reached after 10 and 120 s, respectively. The rate of insertion of AmB into POPC-sterol membranes is thus increased through formulation as AmB-SCS. Moreover, the differences in monolayer surface pressure and SANS structure-change equilibration times suggest significant rearrangement of AmB within these membranes following insertion. The reduced times to equilibrium for the POPC-ergosterol vs POPC-cholesterol systems are consistent with the known differences in affinity of AmB for these two sterols, and the reduced time to equilibrium for AmB-SCS interaction with POPC-ergosterol membranes vs that for free AmB is consistent with the reduced host toxicity of Amphotec.
Collapse
Affiliation(s)
- F Foglia
- †Institute of Pharmaceutical Science, King's College London, Franklin Wilkins Building, 150 Stamford Street, London SE1 9NH, U.K
| | | | | | | | | | - M J Lawrence
- †Institute of Pharmaceutical Science, King's College London, Franklin Wilkins Building, 150 Stamford Street, London SE1 9NH, U.K
| | - D J Barlow
- †Institute of Pharmaceutical Science, King's College London, Franklin Wilkins Building, 150 Stamford Street, London SE1 9NH, U.K
| |
Collapse
|
45
|
Vale-Silva LA, Sanglard D. Tipping the balance both ways: drug resistance and virulence in Candida glabrata. FEMS Yeast Res 2015; 15:fov025. [PMID: 25979690 DOI: 10.1093/femsyr/fov025] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2015] [Indexed: 01/20/2023] Open
Abstract
Among existing fungal pathogens, Candida glabrata is outstanding in its capacity to rapidly develop resistance to currently used antifungal agents. Resistance to the class of azoles, which are still widely used agents, varies in proportion (from 5 to 20%) depending on geographical area. Moreover, resistance to the class of echinocandins, which was introduced in the late 1990s, is rising in several institutions. The recent emergence of isolates with acquired resistance to both classes of agents is a major concern since alternative therapeutic options are scarce. Although considered less pathogenic than C. albicans, C. glabrata has still evolved specific virulence traits enabling its survival and propagation in colonized and infected hosts. Development of drug resistance is usually associated with fitness costs, and this notion is documented across several microbial species. Interestingly, azole resistance in C. glabrata has revealed the opposite. Experimental models of infection showed enhanced virulence of azole-resistant isolates. Moreover, azole resistance could be associated with specific changes in adherence properties to epithelial cells or innate immunity cells (macrophages), both of which contribute to virulence changes. Here we will summarize the current knowledge on C. glabrata drug resistance and also discuss the consequences of drug resistance acquisition on the balance between C. glabrata and its hosts.
Collapse
Affiliation(s)
- Luis A Vale-Silva
- Institute of Microbiology, University of Lausanne and University Hospital Center, CH-1011 Lausanne, Switzerland
| | - Dominique Sanglard
- Institute of Microbiology, University of Lausanne and University Hospital Center, CH-1011 Lausanne, Switzerland
| |
Collapse
|
46
|
Xie JL, Polvi EJ, Shekhar-Guturja T, Cowen LE. Elucidating drug resistance in human fungal pathogens. Future Microbiol 2014; 9:523-42. [PMID: 24810351 DOI: 10.2217/fmb.14.18] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Fungal pathogens cause life-threatening infections in immunocompetent and immunocompromised individuals. Millions of people die each year due to fungal infections, comparable to the mortality attributable to tuberculosis or malaria. The three most prevalent fungal pathogens are Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus. Fungi are eukaryotes like their human host, making it challenging to identify fungal-specific therapeutics. There is a limited repertoire of antifungals in clinical use, and drug resistance and host toxicity compromise the clinical utility. The three classes of antifungals for treatment of invasive infections are the polyenes, azoles and echinocandins. Understanding mechanisms of resistance to these antifungals has been accelerated by global and targeted approaches, which have revealed that antifungal drug resistance is a complex phenomenon involving multiple mechanisms. Development of novel strategies to block the emergence of drug resistance and render resistant pathogens responsive to antifungals will be critical to treating life-threatening fungal infections.
Collapse
Affiliation(s)
- Jinglin Lucy Xie
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | | | | | | |
Collapse
|
47
|
Brunke S, Seider K, Fischer D, Jacobsen ID, Kasper L, Jablonowski N, Wartenberg A, Bader O, Enache-Angoulvant A, Schaller M, d'Enfert C, Hube B. One small step for a yeast--microevolution within macrophages renders Candida glabrata hypervirulent due to a single point mutation. PLoS Pathog 2014; 10:e1004478. [PMID: 25356907 PMCID: PMC4214790 DOI: 10.1371/journal.ppat.1004478] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 09/17/2014] [Indexed: 12/25/2022] Open
Abstract
Candida glabrata is one of the most common causes of candidemia, a life-threatening, systemic fungal infection, and is surpassed in frequency only by Candida albicans. Major factors contributing to the success of this opportunistic pathogen include its ability to readily acquire resistance to antifungals and to colonize and adapt to many different niches in the human body. Here we addressed the flexibility and adaptability of C. glabrata during interaction with macrophages with a serial passage approach. Continuous co-incubation of C. glabrata with a murine macrophage cell line for over six months resulted in a striking alteration in fungal morphology: The growth form changed from typical spherical yeasts to pseudohyphae-like structures – a phenotype which was stable over several generations without any selective pressure. Transmission electron microscopy and FACS analyses showed that the filamentous-like morphology was accompanied by changes in cell wall architecture. This altered growth form permitted faster escape from macrophages and increased damage of macrophages. In addition, the evolved strain (Evo) showed transiently increased virulence in a systemic mouse infection model, which correlated with increased organ-specific fungal burden and inflammatory response (TNFα and IL-6) in the brain. Similarly, the Evo mutant significantly increased TNFα production in the brain on day 2, which is mirrored in macrophages confronted with the Evo mutant, but not with the parental wild type. Whole genome sequencing of the Evo strain, genetic analyses, targeted gene disruption and a reverse microevolution experiment revealed a single nucleotide exchange in the chitin synthase-encoding CHS2 gene as the sole basis for this phenotypic alteration. A targeted CHS2 mutant with the same SNP showed similar phenotypes as the Evo strain under all experimental conditions tested. These results indicate that microevolutionary processes in host-simulative conditions can elicit adaptations of C. glabrata to distinct host niches and even lead to hypervirulent strains. Evolution is not limited to making new species emerge and others perish over the millennia. It is also a central force in shorter-term interactions between microbes and hosts. A good example can be found in fungi, which are an underestimated cause of human diseases. Some fungi exist as commensals, and have adapted well to life on human epithelia. But as facultative pathogens, they face a different, hostile environment. We tested the ability of C. glabrata, a pathogen closely related to baker's yeast, to adapt to macrophages. We found that by adaptation, it changed its growth type completely. This allowed the fungus to escape the phagocytes, and increased its virulence in a mouse model. Sequencing the complete genome revealed surprisingly few mutations. Further analyses allowed us to detect the single mutation responsible for the phenotype, and to recreate it in the parental strain. Our work shows that fungi can adapt to immune cells, and that this adaptation can lead to an increased virulence. Since commensals are continuously exposed to host cells, we suggest that this ability could lead to unexpected phenotype changes, including an increase in virulence potential.
Collapse
Affiliation(s)
- Sascha Brunke
- Integrated Research and Treatment Center, Sepsis und Sepsisfolgen, Center for Sepsis Control and Care (CSCC), Universitätsklinikum Jena, Jena, Germany
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Jena, Germany
| | - Katja Seider
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Jena, Germany
| | - Daniel Fischer
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Jena, Germany
| | - Ilse D. Jacobsen
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Jena, Germany
| | - Lydia Kasper
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Jena, Germany
| | - Nadja Jablonowski
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Jena, Germany
| | - Anja Wartenberg
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Jena, Germany
| | - Oliver Bader
- Institute for Medical Microbiology and German National Reference Centre for Systemic Mycoses, University Medical Centre Göttingen, Göttingen, Germany
| | - Adela Enache-Angoulvant
- APHP, Hôpital Bicêtre, Service de Bactériologie-Virologie-Parasitologie, Laboratoire de Parasitologie-Mycologie, Kremlin-Bicêtre, France
| | - Martin Schaller
- Department of Dermatology, Eberhard-Karls-University, Tübingen, Germany
| | - Christophe d'Enfert
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC2019, Paris, France
| | - Bernhard Hube
- Integrated Research and Treatment Center, Sepsis und Sepsisfolgen, Center for Sepsis Control and Care (CSCC), Universitätsklinikum Jena, Jena, Germany
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Jena, Germany
- Friedrich Schiller University, Jena, Germany
- * E-mail:
| |
Collapse
|
48
|
The production of reactive oxygen species is a universal action mechanism of Amphotericin B against pathogenic yeasts and contributes to the fungicidal effect of this drug. Antimicrob Agents Chemother 2014; 58:6627-38. [PMID: 25155595 DOI: 10.1128/aac.03570-14] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Amphotericin B (AMB) is an antifungal drug that binds to ergosterol and forms pores at the cell membrane, causing the loss of ions. In addition, AMB induces the accumulation of reactive oxygen species (ROS), and although these molecules have multiple deleterious effects on fungal cells, their specific role in the action mechanism of AMB remains unknown. In this work, we studied the role of ROS in the action mechanism of AMB. We determined the intracellular induction of ROS in 44 isolates of different pathogenic yeast species (Candida albicans, Candida parapsilosis, Candida glabrata, Candida tropicalis, Candida krusei, Cryptococcus neoformans, and Cryptococcus gattii). We also characterized the production of ROS in AMB-resistant isolates. We found that AMB induces the formation of ROS in all the species tested. The inhibition of the mitochondrial respiratory chain by rotenone blocked the induction of ROS by AMB and provided protection from the killing action of the antifungal. Moreover, this phenomenon was absent in strains that displayed resistance to AMB. These strains showed an alteration in the respiration rate and mitochondrial membrane potential and also had higher catalase activity than that of the AMB-susceptible strains. Consistently, AMB failed to induce protein carbonylation in the resistant strains. Our data demonstrate that the production of ROS by AMB is a universal and important action mechanism that is correlated with the fungicidal effect and might explain the low rate of resistance to the molecule. Finally, these data provide an opportunity to design new strategies to improve the efficacy of this antifungal.
Collapse
|
49
|
Schwarzmüller T, Ma B, Hiller E, Istel F, Tscherner M, Brunke S, Ames L, Firon A, Green B, Cabral V, Marcet-Houben M, Jacobsen ID, Quintin J, Seider K, Frohner I, Glaser W, Jungwirth H, Bachellier-Bassi S, Chauvel M, Zeidler U, Ferrandon D, Gabaldón T, Hube B, d'Enfert C, Rupp S, Cormack B, Haynes K, Kuchler K. Systematic phenotyping of a large-scale Candida glabrata deletion collection reveals novel antifungal tolerance genes. PLoS Pathog 2014; 10:e1004211. [PMID: 24945925 PMCID: PMC4063973 DOI: 10.1371/journal.ppat.1004211] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 05/13/2014] [Indexed: 11/28/2022] Open
Abstract
The opportunistic fungal pathogen Candida glabrata is a frequent cause of candidiasis, causing infections ranging from superficial to life-threatening disseminated disease. The inherent tolerance of C. glabrata to azole drugs makes this pathogen a serious clinical threat. To identify novel genes implicated in antifungal drug tolerance, we have constructed a large-scale C. glabrata deletion library consisting of 619 unique, individually bar-coded mutant strains, each lacking one specific gene, all together representing almost 12% of the genome. Functional analysis of this library in a series of phenotypic and fitness assays identified numerous genes required for growth of C. glabrata under normal or specific stress conditions, as well as a number of novel genes involved in tolerance to clinically important antifungal drugs such as azoles and echinocandins. We identified 38 deletion strains displaying strongly increased susceptibility to caspofungin, 28 of which encoding proteins that have not previously been linked to echinocandin tolerance. Our results demonstrate the potential of the C. glabrata mutant collection as a valuable resource in functional genomics studies of this important fungal pathogen of humans, and to facilitate the identification of putative novel antifungal drug target and virulence genes. Clinical infections by the yeast-like pathogen Candida glabrata have been ever-increasing over the past years. Importantly, C. glabrata is one of the most prevalent causes of drug-refractory fungal infections in humans. We have generated a novel large-scale collection encompassing 619 bar-coded C. glabrata mutants, each lacking a single gene. Extensive profiling of phenotypes reveals a number of novel genes implicated in tolerance to antifungal drugs that interfere with proper cell wall function, as well as genes affecting fitness of C. glabrata both during normal growth and under environmental stress. This fungal deletion collection will be a valuable resource for the community to study mechanisms of virulence and antifungal drug tolerance in C. glabrata, which is particularly relevant in view of the increasing prevalence of infections caused by this important human fungal pathogen.
Collapse
Affiliation(s)
- Tobias Schwarzmüller
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Biao Ma
- Department of Microbiology, Imperial College London, London, United Kingdom
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Ekkehard Hiller
- Molekulare Biotechnologie MBT Fraunhofer Institut für Grenzflächen- und Bioverfahrenstechnik IGB Fraunhofer, Stuttgart, Germany
| | - Fabian Istel
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Michael Tscherner
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Sascha Brunke
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
- Center for Sepsis Control and Care, CSCC, Jena University Hospital, Jena, Germany
| | - Lauren Ames
- Department of Microbiology, Imperial College London, London, United Kingdom
- Biosciences, College of Life & Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Arnaud Firon
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC2019, Paris, France
| | - Brian Green
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Vitor Cabral
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC2019, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur, Paris, France
| | - Marina Marcet-Houben
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG), Barcelona, Spain
| | - Ilse D. Jacobsen
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
- Center for Sepsis Control and Care, CSCC, Jena University Hospital, Jena, Germany
| | - Jessica Quintin
- UPR 9022 du CNRS, Université de Strasbourg, Equipe Fondation Recherche Médicale, Institut de Biologie Moléculaire et Cellulaire, Strasbourg, France
| | - Katja Seider
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
| | - Ingrid Frohner
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Walter Glaser
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Helmut Jungwirth
- Institut für Molekulare Biowissenschaften, Universität Graz, Graz, Austria
| | - Sophie Bachellier-Bassi
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
| | - Murielle Chauvel
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
| | - Ute Zeidler
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
| | - Dominique Ferrandon
- UPR 9022 du CNRS, Université de Strasbourg, Equipe Fondation Recherche Médicale, Institut de Biologie Moléculaire et Cellulaire, Strasbourg, France
| | - Toni Gabaldón
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Bernhard Hube
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
- Center for Sepsis Control and Care, CSCC, Jena University Hospital, Jena, Germany
| | - Christophe d'Enfert
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC2019, Paris, France
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Steffen Rupp
- Molekulare Biotechnologie MBT Fraunhofer Institut für Grenzflächen- und Bioverfahrenstechnik IGB Fraunhofer, Stuttgart, Germany
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Brendan Cormack
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Ken Haynes
- Department of Microbiology, Imperial College London, London, United Kingdom
- Biosciences, College of Life & Environmental Sciences, University of Exeter, Exeter, United Kingdom
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Karl Kuchler
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| |
Collapse
|
50
|
Taff HT, Mitchell KF, Edward JA, Andes DR. Mechanisms of Candida biofilm drug resistance. Future Microbiol 2014; 8:1325-37. [PMID: 24059922 DOI: 10.2217/fmb.13.101] [Citation(s) in RCA: 267] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Candida commonly adheres to implanted medical devices, growing as a resilient biofilm capable of withstanding extraordinarily high antifungal concentrations. As currently available antifungals have minimal activity against biofilms, new drugs to treat these recalcitrant infections are urgently needed. Recent investigations have begun to shed light on the mechanisms behind the profound resistance associated with the biofilm mode of growth. This resistance appears to be multifactorial, involving both mechanisms similar to conventional, planktonic antifungal resistance, such as increased efflux pump activity, as well as mechanisms specific to the biofilm lifestyle. A unique biofilm property is the production of an extracellular matrix. Two components of this material, β-glucan and extracellular DNA, promote biofilm resistance to multiple antifungals. Biofilm formation also engages several stress response pathways that impair the activity of azole drugs. Resistance within a biofilm is often heterogeneous, with the development of a subpopulation of resistant persister cells. In this article we review the molecular mechanisms underlying Candida biofilm antifungal resistance and their relative contributions during various growth phases.
Collapse
Affiliation(s)
- Heather T Taff
- Departments of Medicine & Medical Microbiology & Immunology, University of Wisconsin, Madison, Wisconsin, USA
| | | | | | | |
Collapse
|