1
|
Ning YT, Sun TS, Dai RC, Luo ZY, Yu SY, Zhang G, Mei YN, Lin YL, Hasi CL, Chen SCA, Kong FR, Xiao M, Xu YC, Zhang L. Emergence of multiple fluconazole-resistant Candida parapsilosis sensu stricto clones with persistence and transmission in China. J Antimicrob Chemother 2024; 79:128-133. [PMID: 37991189 PMCID: PMC10761258 DOI: 10.1093/jac/dkad356] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 11/03/2023] [Indexed: 11/23/2023] Open
Abstract
OBJECTIVES We explored the epidemiological and molecular characteristics of Candida parapsilosis sensu stricto isolates in China, and their mechanisms of azole resistance. METHODS Azole susceptibilities of 2318 non-duplicate isolates were determined using CLSI broth microdilution. Isolates were genotyped by a microsatellite typing method. Molecular resistance mechanisms were also studied and functionally validated by CRISPR/Cas9-based genetic alterations. RESULTS Fluconazole resistance occurred in 2.4% (n = 56) of isolates, and these isolates showed a higher frequency of distribution in ICU inpatients compared with susceptible isolates (48.2%, n = 27/56 versus 27.8%, 613/2208; P = 0.019). Microsatellite-genotyping analysis yielded 29 genotypes among 56 fluconazole-resistant isolates, of which 10 genotypes, including 37 isolates, belonged to clusters, persisting and transmitting in Chinese hospitals for 1-29 months. Clusters harbouring Erg11Y132F (5/10; 50%) were predominant in China. Among these, the second most dominant cluster MT07, including seven isolates, characteristically harbouring Erg11Y132F and Mrr1Q625K, lent its carriage to being one of the strongest associations with cross-resistance and high MICs of fluconazole (>256 mg/L) and voriconazole (2-8 mg/L), causing transmission across two hospitals. Among mutations tested, Mrr1Q625K led to the highest-level increase of fluconazole MIC (32-fold), while mutations located within or near the predicted transcription factor domain of Tac1 (D440Y, T492M and L518F) conferred cross-resistance to azoles. CONCLUSIONS This study is the first Chinese report of persistence and transmissions of multiple fluconazole-resistant C. parapsilosis sensu stricto clones harbouring Erg11Y132F, and the first demonstration of the mutations Erg11G307A, Mrr1Q625K, Tac1L263S, Tac1D440Y and Tac1T492M as conferring resistance to azoles.
Collapse
Affiliation(s)
- Ya-Ting Ning
- Department of Laboratory Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- Graduate School, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - Tian-Shu Sun
- Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
- Clinical Biobank, Medical Research Centre, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science, Beijing, China
| | - Rong-Chen Dai
- Department of Laboratory Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Zheng-Yu Luo
- Department of Laboratory Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- Graduate School, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - Shu-Ying Yu
- Department of Laboratory Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - Ge Zhang
- Department of Laboratory Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - Ya-Ning Mei
- Department of Laboratory Medicine, Jiangsu Province Hospital and Nanjing Medical University First Affiliated Hospital, Nanjing, China
| | - Yu-Lan Lin
- Department of Laboratory Medicine, Fujian Key Laboratory of Laboratory Medicine, The First Affiliated Hospital, Fujian Medical University, Fujian, China
| | - Chao-Lu Hasi
- Department of Laboratory Medicine, The First Hospital of Shanxi Medical University, Shanxi, China
| | - Sharon C A Chen
- Centre for Infectious Diseases and Microbiology Laboratory Services, Institute of Clinical Pathology and Medical Research, New South Wales Health Pathology, Westmead Hospital, University of Sydney, Sydney, Australia
| | - Fan-Rong Kong
- Centre for Infectious Diseases and Microbiology Laboratory Services, Institute of Clinical Pathology and Medical Research, New South Wales Health Pathology, Westmead Hospital, University of Sydney, Sydney, Australia
| | - Meng Xiao
- Department of Laboratory Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - Ying-Chun Xu
- Department of Laboratory Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - Li Zhang
- Department of Laboratory Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| |
Collapse
|
2
|
Franconi I, Rizzato C, Poma N, Tavanti A, Lupetti A. Candida parapsilosis sensu stricto Antifungal Resistance Mechanisms and Associated Epidemiology. J Fungi (Basel) 2023; 9:798. [PMID: 37623569 PMCID: PMC10456088 DOI: 10.3390/jof9080798] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/18/2023] [Accepted: 07/25/2023] [Indexed: 08/26/2023] Open
Abstract
Fungal diseases cause millions of deaths per year worldwide. Antifungal resistance has become a matter of great concern in public health. In recent years rates of non-albicans species have risen dramatically. Candida parapsilosis is now reported to be the second most frequent species causing candidemia in several countries in Europe, Latin America, South Africa and Asia. Rates of acquired azole resistance are reaching a worrisome threshold from multiple reports as in vitro susceptibility testing is now starting also to explore tolerance and heteroresistance to antifungal compounds. With this review, the authors seek to evaluate known antifungal resistance mechanisms and their worldwide distribution in Candida species infections with a specific focus on C. parapsilosis.
Collapse
Affiliation(s)
- Iacopo Franconi
- Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Via San Zeno, 37, 56127 Pisa, Italy; (I.F.); (C.R.)
| | - Cosmeri Rizzato
- Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Via San Zeno, 37, 56127 Pisa, Italy; (I.F.); (C.R.)
| | - Noemi Poma
- Department of Biology, University of Pisa, Via San Zeno, 37, 56127 Pisa, Italy; (N.P.); (A.T.)
| | - Arianna Tavanti
- Department of Biology, University of Pisa, Via San Zeno, 37, 56127 Pisa, Italy; (N.P.); (A.T.)
| | - Antonella Lupetti
- Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Via San Zeno, 37, 56127 Pisa, Italy; (I.F.); (C.R.)
| |
Collapse
|
3
|
Rabaan AA, Sulaiman T, Al-Ahmed SH, Buhaliqah ZA, Buhaliqah AA, AlYuosof B, Alfaresi M, Al Fares MA, Alwarthan S, Alkathlan MS, Almaghrabi RS, Abuzaid AA, Altowaileb JA, Al Ibrahim M, AlSalman EM, Alsalman F, Alghounaim M, Bueid AS, Al-Omari A, Mohapatra RK. Potential Strategies to Control the Risk of Antifungal Resistance in Humans: A Comprehensive Review. Antibiotics (Basel) 2023; 12:antibiotics12030608. [PMID: 36978475 PMCID: PMC10045400 DOI: 10.3390/antibiotics12030608] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 03/09/2023] [Accepted: 03/11/2023] [Indexed: 03/30/2023] Open
Abstract
Fungal infections are becoming one of the main causes of morbidity and mortality in people with weakened immune systems. Mycoses are becoming more common, despite greater knowledge and better treatment methods, due to the regular emergence of resistance to the antifungal medications used in clinical settings. Antifungal therapy is the mainstay of patient management for acute and chronic mycoses. However, the limited availability of antifungal drug classes limits the range of available treatments. Additionally, several drawbacks to treating mycoses include unfavourable side effects, a limited activity spectrum, a paucity of targets, and fungal resistance, all of which continue to be significant issues in developing antifungal drugs. The emergence of antifungal drug resistance has eliminated accessible drug classes as treatment choices, which significantly compromises the clinical management of fungal illnesses. In some situations, the emergence of strains resistant to many antifungal medications is a major concern. Although new medications have been developed to address this issue, antifungal drug resistance has grown more pronounced, particularly in patients who need long-term care or are undergoing antifungal prophylaxis. Moreover, the mechanisms that cause resistance must be well understood, including modifications in drug target affinities and abundances, along with biofilms and efflux pumps that diminish intracellular drug levels, to find novel antifungal drugs and drug targets. In this review, different classes of antifungal agents, and their resistance mechanisms, have been discussed. The latter part of the review focuses on the strategies by which we can overcome this serious issue of antifungal resistance in humans.
Collapse
Affiliation(s)
- Ali A Rabaan
- Molecular Diagnostic Laboratory, Johns Hopkins Aramco Healthcare, Dhahran 31311, Saudi Arabia
- College of Medicine, Alfaisal University, Riyadh 11533, Saudi Arabia
- Department of Public Health and Nutrition, The University of Haripur, Haripur 22610, Pakistan
| | - Tarek Sulaiman
- Infectious Diseases Section, Medical Specialties Department, King Fahad Medical City, Riyadh 12231, Saudi Arabia
| | - Shamsah H Al-Ahmed
- Specialty Paediatric Medicine, Qatif Central Hospital, Qatif 32654, Saudi Arabia
| | - Zainab A Buhaliqah
- Department of Family Medicine, Primary Healthcare Center, Dammam 32433, Saudi Arabia
| | - Ali A Buhaliqah
- College of Medicine, Alfaisal University, Riyadh 11533, Saudi Arabia
| | - Buthina AlYuosof
- Directorate of Public Health, Dammam Network, Eastern Health Cluster, Dammam 31444, Saudi Arabia
| | - Mubarak Alfaresi
- Department of Pathology and Laboratory Medicine, Zayed Military Hospital, Abu Dhabi 3740, United Arab Emirates
- Department of Pathology, College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai 505055, United Arab Emirates
| | - Mona A Al Fares
- Department of Internal Medicine, King Abdulaziz University Hospital, Jeddah 21589, Saudi Arabia
| | - Sara Alwarthan
- Department of Internal Medicine, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam 34212, Saudi Arabia
| | - Mohammed S Alkathlan
- Infectious Diseases Department, King Fahad Specialist Hospital, Buraydah 52382, Saudi Arabia
| | - Reem S Almaghrabi
- Organ Transplant Center of Excellence, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia
| | - Abdulmonem A Abuzaid
- Medical Microbiology Department, Security Forces Hospital Programme, Dammam 32314, Saudi Arabia
| | - Jaffar A Altowaileb
- Microbiology Laboratory, Laboratory Department, Qatif Central Hospital, Qatif 32654, Saudi Arabia
| | - Maha Al Ibrahim
- Microbiology Laboratory, Laboratory Department, Qatif Central Hospital, Qatif 32654, Saudi Arabia
| | - Eman M AlSalman
- Department of Family Medicine, Primary Health Care Centers, Qatif Health Network, Qatif 31911, Saudi Arabia
| | - Fatimah Alsalman
- Department of Emergency Medicine, Oyun City Hospital, Al-Ahsa 36312, Saudi Arabia
| | | | - Ahmed S Bueid
- Microbiology Laboratory, King Faisal General Hospital, Al-Ahsa 31982, Saudi Arabia
| | - Awad Al-Omari
- College of Medicine, Alfaisal University, Riyadh 11533, Saudi Arabia
- Research Center, Dr. Sulaiman Al Habib Medical Group, Riyadh 11372, Saudi Arabia
| | - Ranjan K Mohapatra
- Department of Chemistry, Government College of Engineering, Keonjhar 758002, India
| |
Collapse
|
4
|
Cai H, Zhang H, Guo DH, Wang Y, Gu J. Genomic Data Mining Reveals Abundant Uncharacterized Transporters in Coccidioides immitis and Coccidioides posadasii. J Fungi (Basel) 2022; 8:jof8101064. [PMID: 36294626 PMCID: PMC9604845 DOI: 10.3390/jof8101064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 10/01/2022] [Accepted: 10/08/2022] [Indexed: 11/16/2022] Open
Abstract
Coccidioides immitis and Coccidioides posadasii are causative agents of coccidioidomycosis, commonly known as Valley Fever. The increasing Valley Fever cases in the past decades, the expansion of endemic regions, and the rising azole drug-resistant strains have underscored an urgent need for a better understanding of Coccidioides biology and new antifungal strategies. Transporters play essential roles in pathogen survival, growth, infection, and adaptation, and are considered as potential drug targets. However, the composition and roles of transport machinery in Coccidioides remain largely unknown. In this study, genomic data mining revealed an abundant, uncharacterized repertoire of transporters in Coccidioides genomes. The catalog included 1288 and 1235 transporter homologs in C. immitis and C. posadasii, respectively. They were further annotated to class, subclass, family, subfamily and range of substrates based on the Transport Classification (TC) system. They may play diverse roles in nutrient uptake, metabolite secretion, ion homeostasis, drug efflux, or signaling. This study represents an initial effort for a systems-level characterization of the transport machinery in these understudied fungal pathogens.
Collapse
Affiliation(s)
- Hong Cai
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX 78249, USA
- South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Hao Zhang
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX 78249, USA
- South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Daniel H. Guo
- Strake Jesuit College Preparatory, Houston, TX 77036, USA
| | - Yufeng Wang
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX 78249, USA
- South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX 78249, USA
- Correspondence: (Y.W.); (J.G.)
| | - Jianying Gu
- Department of Biology, College of Staten Island, City University of New York, Staten Island, New York, NY 10314, USA
- Correspondence: (Y.W.); (J.G.)
| |
Collapse
|
5
|
Kukurudz RJ, Chapel M, Wonitowy Q, Adamu Bukari AR, Sidney B, Sierhuis R, Gerstein AC. Acquisition of cross-azole tolerance and aneuploidy in Candida albicans strains evolved to posaconazole. G3 (BETHESDA, MD.) 2022; 12:jkac156. [PMID: 35881695 PMCID: PMC9434289 DOI: 10.1093/g3journal/jkac156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 06/13/2022] [Indexed: 12/30/2022]
Abstract
A number of in vitro studies have examined the acquisition of drug resistance to the triazole fluconazole, a first-line treatment for many Candida infections. Much less is known about posaconazole, a newer triazole. We conducted the first in vitro experimental evolution of replicates from 8 diverse strains of Candida albicans in a high level of the fungistatic drug posaconazole. Approximately half of the 132 evolved replicates survived 50 generations of evolution, biased toward some of the strain backgrounds. We found that although increases in drug resistance were rare, increases in drug tolerance (the slow growth of a subpopulation of cells in a level of drug above the resistance level) were common across strains. We also found that adaptation to posaconazole resulted in widespread cross-tolerance to other azole drugs. Widespread aneuploidy was observed in evolved replicates from some strain backgrounds. Trisomy of at least one of chromosomes 3, 6, and R was identified in 11 of 12 whole-genome sequenced evolved SC5314 replicates. These findings document rampant evolved cross-tolerance among triazoles and highlight that increases in drug tolerance can evolve independently of drug resistance in a diversity of C. albicans strain backgrounds.
Collapse
Affiliation(s)
- Rebekah J Kukurudz
- Department of Microbiology, The University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Madison Chapel
- Department of Microbiology, The University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Quinn Wonitowy
- Department of Microbiology, The University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | | | - Brooke Sidney
- Department of Microbiology, The University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Riley Sierhuis
- Department of Microbiology, The University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Aleeza C Gerstein
- Department of Microbiology, The University of Manitoba, Winnipeg, MB R3T 2N2, Canada
- Department of Statistics, The University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| |
Collapse
|
6
|
Synergistic In Vitro Interaction of Isavuconazole and Isoquercitrin against Candida glabrata. J Fungi (Basel) 2022; 8:jof8050525. [PMID: 35628780 PMCID: PMC9147185 DOI: 10.3390/jof8050525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 05/14/2022] [Accepted: 05/19/2022] [Indexed: 02/05/2023] Open
Abstract
In vitro interactions of broad-spectrum azole isavuconazole with flavonoid isoquercitrin were evaluated by a broth microdilution checkerboard technique based on the European Committee on Antimicrobial Susceptibility Testing (EUCAST) reference methodology for antifungal susceptibility testing against 60 Candida strains belonging to the species Candida albicans (n = 10), Candida glabrata (n = 30), Candida kefyr (n = 6), Candida krusei (n = 5), Candida parapsilosis (n = 4), and Candida tropicalis (n = 5). The results were analyzed with the fractional inhibitory concentration index and by response surface analysis based on the Bliss model. Synergy was found for all C. glabrata strains, when the results were interpreted by the fractional inhibitory concentration index, and for 60% of the strains when response surface analysis was used. Interaction for all other species was indifferent for all strains tested, whatever interpretation model used. Importantly, antagonistic interaction was never observed.
Collapse
|
7
|
Deciphering the Mrr1/Mdr1 Pathway in Azole Resistance of Candida auris. Antimicrob Agents Chemother 2022; 66:e0006722. [PMID: 35343781 DOI: 10.1128/aac.00067-22] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Candida auris is an emerging yeast pathogen with a remarkable ability to develop antifungal resistance, in particular to fluconazole and other azoles. Azole resistance in C. auris was shown to result from different mechanisms, such as mutations in the target gene ERG11 or gain-of-function (GOF) mutations in the transcription factor TAC1b and overexpression of the drug transporter Cdr1. The roles of the transcription factor Mrr1 and of the drug transporter Mdr1 in azole resistance is still unclear. Previous works showed that deletion of MRR1 or MDR1 had no or little impact on azole susceptibility of C. auris. However, an amino acid substitution in Mrr1 (N647T) was identified in most C. auris isolates of clade III that were fluconazole resistant. This study aimed at investigating the role of the transcription factor Mrr1 in azole resistance of C. auris. While the MRR1N647T mutation was always concomitant to hot spot ERG11 mutations, MRR1 deletion in one of these isolates only resulted in a modest decrease of azole MICs. However, introduction of the MRR1N647T mutation in an azole-susceptible C. auris isolate from another clade with wild-type MRR1 and ERG11 alleles resulted in significant increase of fluconazole and voriconazole MICs. We demonstrated that this MRR1 mutation resulted in reduced azole susceptibility via upregulation of the drug transporter MDR1 and not CDR1. In conclusion, this work demonstrates that the Mrr1-Mdr1 axis may contribute to C. auris azole resistance by mechanisms that are independent from ERG11 mutations and from CDR1 upregulation.
Collapse
|
8
|
Rogers TR, Verweij PE, Castanheira M, Dannaoui E, White PL, Arendrup MC. OUP accepted manuscript. J Antimicrob Chemother 2022; 77:2053-2073. [PMID: 35703391 PMCID: PMC9333407 DOI: 10.1093/jac/dkac161] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The increasing incidence and changing epidemiology of invasive fungal infections continue to present many challenges to their effective management. The repertoire of antifungal drugs available for treatment is still limited although there are new antifungals on the horizon. Successful treatment of invasive mycoses is dependent on a mix of pathogen-, host- and antifungal drug-related factors. Laboratories need to be adept at detection of fungal pathogens in clinical samples in order to effectively guide treatment by identifying isolates with acquired drug resistance. While there are international guidelines on how to conduct in vitro antifungal susceptibility testing, these are not performed as widely as for bacterial pathogens. Furthermore, fungi generally are recovered in cultures more slowly than bacteria, and often cannot be cultured in the laboratory. Therefore, non-culture-based methods, including molecular tests, to detect fungi in clinical specimens are increasingly important in patient management and are becoming more reliable as technology improves. Molecular methods can also be used for detection of target gene mutations or other mechanisms that predict antifungal drug resistance. This review addresses acquired antifungal drug resistance in the principal human fungal pathogens and describes known resistance mechanisms and what in-house and commercial tools are available for their detection. It is emphasized that this approach should be complementary to culture-based susceptibility testing, given the range of mutations, resistance mechanisms and target genes that may be present in clinical isolates, but may not be included in current molecular assays.
Collapse
Affiliation(s)
| | | | | | | | | | - Maiken Cavling Arendrup
- Unit of Mycology, Statens Serum Institut, Copenhagen, Denmark
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
9
|
Mechanisms of Azole Resistance and Trailing in Candida tropicalis Bloodstream Isolates. J Fungi (Basel) 2021; 7:jof7080612. [PMID: 34436151 PMCID: PMC8396981 DOI: 10.3390/jof7080612] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 07/25/2021] [Accepted: 07/26/2021] [Indexed: 12/13/2022] Open
Abstract
Objectives: Azole-resistant Candida tropicalis has emerged in Asia in the context of its trailing nature, defined by residual growth above minimum inhibitory concentrations (MICs). However, limited investigations in C. tropicalis have focused on the difference of genotypes and molecular mechanisms between these two traits. Methods: Sixty-four non-duplicated C. tropicalis bloodstream isolates collected in 2017 were evaluated for azole MICs by the EUCAST E.def 7.3.1 method, diploid sequence type (DST) by multilocus sequencing typing, and sequences and expression levels of genes encoding ERG11, its transcription factor, UPC2, and efflux pumps (CDR1, CDR2 and MDR1). Results: Isavuconazole showed the highest in vitro activity and trailing against C. tropicalis, followed by voriconazole and fluconazole (geometric mean [GM] MIC, 0.008, 0.090, 1.163 mg/L, respectively; trailing GM, 27.4%, 20.8% and 19.5%, respectively; both overall p < 0.001). Fourteen (21.9%) isolates were non-WT to fluconazole/voriconazole, 12 of which were non-WT to isavuconazole and clustered in clonal complex (CC) 3. Twenty-five (39.1%) isolates were high trailing WT, including all CC2 isolates (44.0%) (containing DST140 and DST98). All azole non-WT isolates carried the ERG11 mutations A395T/W and/or C461T/Y, and most carried the UPC2 mutation T503C/Y. These mutations were not identified in low and high trailing WT isolates. Azole non-WT and high trailing WT isolates exhibited the highest expression levels of ERG11 and MDR1, 3.91- and 2.30-fold, respectively (both overall p < 0.01). Conclusions: Azole resistance and trailing are phenotypically and genotypically different in C. tropicalis. Interference with azole binding and MDR1 up-regulation confer azole resistance and trailing, respectively.
Collapse
|
10
|
Nishimoto AT, Sharma C, Rogers PD. Molecular and genetic basis of azole antifungal resistance in the opportunistic pathogenic fungus Candida albicans. J Antimicrob Chemother 2021; 75:257-270. [PMID: 31603213 DOI: 10.1093/jac/dkz400] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Candida albicans is an opportunistic yeast and the major human fungal pathogen in the USA, as well as in many other regions of the world. Infections with C. albicans can range from superficial mucosal and dermatological infections to life-threatening infections of the bloodstream and vital organs. The azole antifungals remain an important mainstay treatment of candidiasis and therefore the investigation and understanding of the evolution, frequency and mechanisms of azole resistance are vital to improving treatment strategies against this organism. Here the organism C. albicans and the genetic changes and molecular bases underlying the currently known resistance mechanisms to the azole antifungal class are reviewed, including up-regulated expression of efflux pumps, changes in the expression and amino acid composition of the azole target Erg11 and alterations to the organism's typical sterol biosynthesis pathways. Additionally, we update what is known about activating mutations in the zinc cluster transcription factor (ZCF) genes regulating many of these resistance mechanisms and review azole import as a potential contributor to azole resistance. Lastly, investigations of azole tolerance in C. albicans and its implicated clinical significance are reviewed.
Collapse
Affiliation(s)
- Andrew T Nishimoto
- Department of Clinical Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Cheshta Sharma
- Department of Clinical Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - P David Rogers
- Department of Clinical Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| |
Collapse
|
11
|
Nagy F, Tóth Z, Nyikos F, Forgács L, Jakab Á, Borman AM, Majoros L, Kovács R. In vitro and in vivo interaction of caspofungin with isavuconazole against Candida auris planktonic cells and biofilms. Med Mycol 2021; 59:1015-1023. [PMID: 34021571 DOI: 10.1093/mmy/myab032] [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] [Received: 03/16/2021] [Revised: 05/13/2021] [Accepted: 05/19/2021] [Indexed: 02/07/2023] Open
Abstract
The in vitro and in vivo efficacy of caspofungin was determined in combination with isavuconazole against Candida auris. Drug-drug interactions were assessed utilising the fractional inhibitory concentration indices (FICIs), the Bliss independence model and an immunocompromised mouse model. Median planktonic minimum inhibitory concentrations (pMICs) of 23 C. auris isolates were between 0.5 and 2 mg/L and between 0.015 and 4 mg/L for caspofungin and isavuconazole, respectively. Median pMICs for caspofungin and isavuconazole in combination showed 2-128-fold and 2-256-fold decreases, respectively. Caspofungin and isavuconazole showed synergism in 14 out of 23 planktonic isolates (FICI range 0.03-0.5; Bliss cumulative synergy volume range 0-4.83). Median sessile MICs (sMIC) of 14 biofilm-forming isolates were between 32 and > 32 mg/L and between 0.5 and > 2 mg/L for caspofungin and isavuconazole, respectively. Median sMICs for caspofungin and isavuconazole in combination showed 0-128-fold and 0-512-fold decreases, respectively. Caspofungin and isavuconazole showed synergistic interaction in 12 out of 14 sessile isolates (FICI range 0.023-0.5; Bliss cumulative synergy volume range 0.13-234.32). In line with the in vitro findings, synergistic interactions were confirmed by in vivo experiments. The fungal kidney burden decreases were more than 3 log volumes in mice treated with combination of 1 mg/kg caspofungin and 20 mg/kg isavuconazole daily; this difference was statistically significant compared with control mice (p < 0.001). Despite the favourable effect of isavuconazole in combination with caspofungin, further studies are needed to confirm the therapeutic advantage of this combination when treating an infection caused by C. auris.
Collapse
Affiliation(s)
- Fruzsina Nagy
- Department of Medical Microbiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., 4032 Debrecen, Hungary.,Doctoral School of Pharmaceutical Sciences, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| | - Zoltán Tóth
- Department of Medical Microbiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., 4032 Debrecen, Hungary.,Doctoral School of Pharmaceutical Sciences, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary.,Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| | - Fanni Nyikos
- Department of Medical Microbiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., 4032 Debrecen, Hungary
| | - Lajos Forgács
- Department of Medical Microbiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., 4032 Debrecen, Hungary.,Doctoral School of Pharmaceutical Sciences, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| | - Ágnes Jakab
- Department of Molecular Biotechnology and Microbiology, Faculty of Science and Technology, Institute of Biotechnology, University of Debrecen, Debrecen, Hungary
| | - Andrew M Borman
- UK National Mycology Reference Laboratory, Public Health England, Science Quarter, Southmead Hospital, Bristol BS10 5NB, UK.,Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter EX4 4QD, UK
| | - László Majoros
- Department of Medical Microbiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., 4032 Debrecen, Hungary
| | - Renátó Kovács
- Department of Medical Microbiology, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., 4032 Debrecen, Hungary.,Department of Metagenomics, University of Debrecen, Nagyerdei krt. 98, 4032 Debrecen, Hungary
| |
Collapse
|
12
|
Nagy G, Kiss S, Varghese R, Bauer K, Szebenyi C, Kocsubé S, Homa M, Bodai L, Zsindely N, Nagy G, Vágvölgyi C, Papp T. Characterization of Three Pleiotropic Drug Resistance Transporter Genes and Their Participation in the Azole Resistance of Mucor circinelloides. Front Cell Infect Microbiol 2021; 11:660347. [PMID: 33937100 PMCID: PMC8079984 DOI: 10.3389/fcimb.2021.660347] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/19/2021] [Indexed: 02/04/2023] Open
Abstract
Mucormycosis is a life-threatening opportunistic infection caused by certain members of the fungal order Mucorales. This infection is associated with high mortality rate, which can reach nearly 100% depending on the underlying condition of the patient. Treatment of mucormycosis is challenging because these fungi are intrinsically resistant to most of the routinely used antifungal agents, such as most of the azoles. One possible mechanism of azole resistance is the drug efflux catalyzed by members of the ATP binding cassette (ABC) transporter superfamily. The pleiotropic drug resistance (PDR) transporter subfamily of ABC transporters is the most closely associated to drug resistance. The genome of Mucor circinelloides encodes eight putative PDR-type transporters. In this study, transcription of the eight pdr genes has been analyzed after azole treatment. Only the pdr1 showed increased transcript level in response to all tested azoles. Deletion of this gene caused increased susceptibility to posaconazole, ravuconazole and isavuconazole and altered growth ability of the mutant. In the pdr1 deletion mutant, transcript level of pdr2 and pdr6 significantly increased. Deletion of pdr2 and pdr6 was also done to create single and double knock out mutants for the three genes. After deletion of pdr2 and pdr6, growth ability of the mutant strains decreased, while deletion of pdr2 resulted in increased sensitivity against posaconazole, ravuconazole and isavuconazole. Our result suggests that the regulation of the eight pdr genes is interconnected and pdr1 and pdr2 participates in the resistance of the fungus to posaconazole, ravuconazole and isavuconazole.
Collapse
Affiliation(s)
- Gábor Nagy
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
- MTA-SZTE “Lendület” Fungal Pathogenicity Mechanisms Research Group, Department of Microbiology, University of Szeged, Szeged, Hungary
| | - Sándor Kiss
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Rakesh Varghese
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Kitti Bauer
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Csilla Szebenyi
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
- MTA-SZTE “Lendület” Fungal Pathogenicity Mechanisms Research Group, Department of Microbiology, University of Szeged, Szeged, Hungary
| | - Sándor Kocsubé
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Mónika Homa
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
- MTA-SZTE “Lendület” Fungal Pathogenicity Mechanisms Research Group, Department of Microbiology, University of Szeged, Szeged, Hungary
| | - László Bodai
- Department of Biochemistry and Molecular Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Nóra Zsindely
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Gábor Nagy
- Department of Biochemistry and Molecular Biology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Csaba Vágvölgyi
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Tamás Papp
- Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
- MTA-SZTE “Lendület” Fungal Pathogenicity Mechanisms Research Group, Department of Microbiology, University of Szeged, Szeged, Hungary
| |
Collapse
|
13
|
Gamal A, Chu S, McCormick TS, Borroto-Esoda K, Angulo D, Ghannoum MA. Ibrexafungerp, a Novel Oral Triterpenoid Antifungal in Development: Overview of Antifungal Activity Against Candida glabrata. Front Cell Infect Microbiol 2021; 11:642358. [PMID: 33791244 PMCID: PMC8006402 DOI: 10.3389/fcimb.2021.642358] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 02/05/2021] [Indexed: 12/12/2022] Open
Abstract
Systemic infections caused by Candida species are an important cause of morbidity and mortality among immunocompromised and non-immunocompromised patients. In particular, Candida glabrata is an emerging species within the Candida family that causes infections ranging from superficial to life-threatening systemic disease. Echinocandins and azoles are typically the first-line therapies used to treat infections caused by C. glabrata, however, there is an increasing prevalence of resistance to these antifungal agents in patients. Thus, a need exists for novel therapies that demonstrate high efficacy against C. glabrata. Ibrexafungerp is a first-in-class glucan synthase inhibitor with oral availability developed to address this increasing antifungal resistance. Ibrexafungerp demonstrates broad in vitro activity against wild-type, azole-resistant, and echinocandin-resistant C. glabrata species. Furthermore, ibrexafungerp has shown efficacy in low pH environments, which suggests its potential effectiveness in treating vulvovaginal candidiasis. Additional preclinical and clinical studies are needed to further examine the mechanism(s) of ibrexafungerp, including acting as a promising new agent for treating C. glabrata infections.
Collapse
Affiliation(s)
- Ahmed Gamal
- Department of Dermatology, Case Western Reserve University, Cleveland, OH, United States
| | - Sherman Chu
- Department of Dermatology, Case Western Reserve University, Cleveland, OH, United States.,College of Osteopathic Medicine of the Pacific, Northwest (COMP), Lebanon, OR, United States
| | - Thomas S McCormick
- Department of Dermatology, Case Western Reserve University, Cleveland, OH, United States
| | | | | | - Mahmoud A Ghannoum
- Department of Dermatology, Case Western Reserve University, Cleveland, OH, United States.,Department of Dermatology, Center for Medical Mycology, University Hospitals Cleveland Medical Center, Cleveland, OH, United States
| |
Collapse
|
14
|
Camphor and Eucalyptol-Anticandidal Spectrum, Antivirulence Effect, Efflux Pumps Interference and Cytotoxicity. Int J Mol Sci 2021; 22:ijms22020483. [PMID: 33418931 PMCID: PMC7825113 DOI: 10.3390/ijms22020483] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/31/2020] [Accepted: 01/04/2021] [Indexed: 12/27/2022] Open
Abstract
Candidaalbicans represents one of the most common fungal pathogens. Due to its increasing incidence and the poor efficacy of available antifungals, finding novel antifungal molecules is of great importance. Camphor and eucalyptol are bioactive terpenoid plant constituents and their antifungal properties have been explored previously. In this study, we examined their ability to inhibit the growth of different Candida species in suspension and biofilm, to block hyphal transition along with their impact on genes encoding for efflux pumps (CDR1 and CDR2), ergosterol biosynthesis (ERG11), and cytotoxicity to primary liver cells. Camphor showed excellent antifungal activity with a minimal inhibitory concentration of 0.125-0.35 mg/mL while eucalyptol was active in the range of 2-23 mg/mL. The results showed camphor's potential to reduce fungal virulence traits, that is, biofilm establishment and hyphae formation. On the other hand, camphor and eucalyptol treatments upregulated CDR1;CDR2 was positively regulated after eucalyptol application while camphor downregulated it. Neither had an impact on ERG11 expression. The beneficial antifungal activities of camphor were achieved with an amount that was non-toxic to porcine liver cells, making it a promising antifungal compound for future development. The antifungal concentration of eucalyptol caused cytotoxic effects and increased expression of efflux pump genes, which suggests that it is an unsuitable antifungal candidate.
Collapse
|
15
|
Espinel-Ingroff A, Cantón E, Pemán J. Antifungal Resistance among Less Prevalent Candida Non- albicans and Other Yeasts versus Established and under Development Agents: A Literature Review. J Fungi (Basel) 2021; 7:jof7010024. [PMID: 33406771 PMCID: PMC7824324 DOI: 10.3390/jof7010024] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/24/2020] [Accepted: 12/28/2020] [Indexed: 01/10/2023] Open
Abstract
Fungal diseases and antifungal resistance continue to increase, including those caused by rare or emerging species. However, the majority of the published in vitro susceptibility data are for the most common fungal species. We reviewed the literature in order to pool reference minimal inhibitory concentration (MIC) data (Clinical and Laboratory Standards Institute—CLSI and European Committee on Antimicrobial Susceptibility—EUCAST) for rare/non-prevalent Candida and other yeast species. MIC results were compared with those for Candida albicans, C. glabrata, and C. krusei. Data were listed for twenty rare and emerging Candida spp., including C. auris, as well as two Cryptococcus spp., two Trichosporon spp., Saccharomyces cerevisiae and five Malassezia spp. The best detectors of antimicrobial resistance are the breakpoints, which are not available for the less common Candida species. However, epidemiological cutoff values (ECVs/ECOFFs) have been calculated using merely in vitro data for both reference methods for various non-prevalent yeasts and recently the CLSI has established ECVs for other Candida species. The ECV could identify the non-wild type (NWT or mutants) isolates with known resistance mechanisms. Utilizing these ECVs, we were able to report additional percentages of NWT, especially for non-prevalent species, by analyzing the MIC distributions in the literature. In addition, since several antifungal drugs are under development, we are listing MIC data for some of these agents.
Collapse
Affiliation(s)
- Ana Espinel-Ingroff
- Department of Medicine, VCU Medical Center, Richmond, VA 23298, USA
- Correspondence:
| | - Emilia Cantón
- Severe Infection Research Group, Health Research Institute Hospital La Fe, 46026 Valencia, Spain; (E.C.); (J.P.)
| | - Javier Pemán
- Severe Infection Research Group, Health Research Institute Hospital La Fe, 46026 Valencia, Spain; (E.C.); (J.P.)
- Microbiology Department, Hospital Universitari i Politècnic La Fe, 46026 Valencia, Spain
| |
Collapse
|
16
|
Isavuconazole: Mechanism of Action, Clinical Efficacy, and Resistance. J Fungi (Basel) 2020; 6:jof6040324. [PMID: 33260353 PMCID: PMC7712939 DOI: 10.3390/jof6040324] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/10/2020] [Accepted: 11/21/2020] [Indexed: 02/07/2023] Open
Abstract
Increasing incidence of invasive fungal infections combined with a growing population of immunocompromised hosts has created a rising need for antifungal agents. Isavuconazole, a second-generation broad-spectrum triazole with activity against yeasts, dimorphic fungi, and molds, has a favorable safety profile and predictable pharmacokinetics. Patients typically tolerate isavuconazole well with fewer drug-drug interactions. Clinical trials have found it to be noninferior to voriconazole for invasive aspergillosis, an alternative therapy for salvage treatment of mucormycosis, and suitable for stepdown therapy with invasive candidiasis. Cross-resistance with other triazoles is common. More studies are needed to determine the role of isavuconazole in anti-mold prophylaxis in high-risk patients.
Collapse
|
17
|
Guan M, Xia P, Tian M, Chen D, Zhang X. Molecular fingerprints of conazoles via functional genomic profiling of Saccharomyces cerevisiae. Toxicol In Vitro 2020; 69:104998. [PMID: 32919014 DOI: 10.1016/j.tiv.2020.104998] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/02/2020] [Accepted: 09/06/2020] [Indexed: 10/23/2022]
Abstract
Conazoles were designed to inhibit ergosterol biosynthesis. Conazoles have been widely used as agricultural fungicides and are frequently detected in the environment. Although conazoles have been reported to have adverse effects, such as potential carcinogenic effects, the underlying molecular mechanisms of toxicity remain unclear. Here, the molecular fingerprints of five conazoles (propiconazole (Pro), penconazole (Pen), tebuconazole (Teb), flusilazole (Flu) and epoxiconazole (Epo)) were assessed in Saccharomyces cerevisiae (yeast) via functional genome-wide knockout mutant profiling. A total of 169 (4.49%), 176 (4.67%), 198 (5.26%), 218 (5.79%) and 173 (4.59%) responsive genes were identified at three concentrations (IC50, IC20 and IC10) of Pro, Pen, Teb, Flu and Epo, respectively. The five conazoles tended to have similar gene mutant fingerprints and toxicity mechanisms. "Ribosome" (sce03010) and "cytoplasmic translation" (GO: 0002181) were the common KEGG pathway and GO biological process term by gene set enrichment analysis of the responsive genes, which suggested that conazoles influenced protein synthesis. Conazoles also affected fatty acids synthesis because "biosynthesis of unsaturated fatty acids" pathway was among the top-ranked KEGG pathways. Moreover, two genes, YGR037C (acyl-CoA-binding protein) and YCR034W (fatty acid elongase), were key fingerprints of conazoles because they played vital roles in conazole-induced toxicity. Overall, the fingerprints derived from the yeast functional genomic screening provide an alternative approach to elucidate the molecular mechanisms of environmental pollutant conazoles.
Collapse
Affiliation(s)
- Miao Guan
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Ave., Nanjing, Jiangsu 210023, China; Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Rd., Nanjing, Jiangsu 210023, China.
| | - Pu Xia
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Ave., Nanjing, Jiangsu 210023, China
| | - Mingming Tian
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Ave., Nanjing, Jiangsu 210023, China
| | - Dong Chen
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Ave., Nanjing, Jiangsu 210023, China; Jiangsu Provincial Academy of Environmental Science, 176 North Jiangdong Rd., Nanjing, Jiangsu 210036, China
| | - Xiaowei Zhang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Ave., Nanjing, Jiangsu 210023, China.
| |
Collapse
|
18
|
Vaitkienė S, Kuliešienė N, Sakalauskaitė S, Bekere L, Krasnova L, Vigante B, Duburs G, Daugelavičius R. Antifungal activity of styrylpyridinium compounds against Candida albicans. Chem Biol Drug Des 2020; 97:253-265. [PMID: 32772494 DOI: 10.1111/cbdd.13777] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 06/24/2020] [Accepted: 07/25/2020] [Indexed: 02/01/2023]
Abstract
We synthesized a set of 13 new and earlier described styrylpyridinium compounds (N-alkyl styrylpyridinium salts with bromide or tosylate anions) in order to evaluate antifungal activity against C. albicans cells, to assay the possible synergism with fluconazole, and to estimate cytotoxicity to mammalian cells. All compounds were synthesized according to a well-known two-step procedure involving alkylation of γ-picoline with appropriate alkyl bromide and further condensation with substituted benzaldehyde. Compounds with long N-alkyl chains (C18 H37 -C20 H41 ) had no antifungal activity against the cells of all tested C. albicans strains. Other styrylpyridinium compounds were able to inhibit yeast growth at the concentrations of 0.06-16 μg/ml. At fungicidal concentrations, the compound with the CN- group was least toxic to mammalian cells, showed the most effective synergism with fluconazole, and only slightly inhibited the respiration of C. albicans. The compound with the 4'-diethylamino group exhibited the strongest fungicidal properties and effectively blocked the respiration of C. albicans cells. However, toxicity to mammalian cells was also high. Summarizing, the results of our study indicate that styrylpyridinium compounds are promising candidates in the development of new antifungal drugs.
Collapse
Affiliation(s)
- Simona Vaitkienė
- Department of Biochemistry, Vytautas Magnus University, Kaunas, Lithuania
| | - Neringa Kuliešienė
- Department of Biochemistry, Vytautas Magnus University, Kaunas, Lithuania
| | | | - Laura Bekere
- Latvian Institute of Organic Synthesis, Riga, Latvia
| | | | | | - Gunars Duburs
- Latvian Institute of Organic Synthesis, Riga, Latvia
| | | |
Collapse
|
19
|
Zhang T, Cao Q, Li N, Liu D, Yuan Y. Transcriptome analysis of fungicide-responsive gene expression profiles in two Penicillium italicum strains with different response to the sterol demethylation inhibitor (DMI) fungicide prochloraz. BMC Genomics 2020; 21:156. [PMID: 32050894 PMCID: PMC7017498 DOI: 10.1186/s12864-020-6564-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Accepted: 02/07/2020] [Indexed: 12/19/2022] Open
Abstract
Background Penicillium italicum (blue mold) is one of citrus pathogens causing undesirable citrus fruit decay even at strictly-controlled low temperatures (< 10 °C) during shipping and storage. P. italicum isolates with considerably high resistance to sterol demethylation inhibitor (DMI) fungicides have emerged; however, mechanism(s) underlying such DMI-resistance remains unclear. In contrast to available elucidation on anti-DMI mechanism for P. digitatum (green mold), how P. italicum DMI-resistance develops has not yet been clarified. Results The present study prepared RNA-sequencing (RNA-seq) libraries for two P. italicum strains (highly resistant (Pi-R) versus highly sensitive (Pi-S) to DMI fungicides), with and without prochloraz treatment, to identify prochloraz-responsive genes facilitating DMI-resistance. After 6 h prochloraz-treatment, comparative transcriptome profiling showed more differentially expressed genes (DEGs) in Pi-R than Pi-S. Functional enrichments identified 15 DEGs in the prochloraz-induced Pi-R transcriptome, simultaneously up-regulated in P. italicum resistance. These included ATP-binding cassette (ABC) transporter-encoding genes, major facilitator superfamily (MFS) transporter-encoding genes, ergosterol (ERG) anabolism component genes ERG2, ERG6 and EGR11 (CYP51A), mitogen-activated protein kinase (MAPK) signaling-inducer genes Mkk1 and Hog1, and Ca2+/calmodulin-dependent kinase (CaMK) signaling-inducer genes CaMK1 and CaMK2. Fragments Per Kilobase per Million mapped reads (FPKM) analysis of Pi-R transcrtiptome showed that prochloraz induced mRNA increase of additional 4 unigenes, including the other two ERG11 isoforms CYP51B and CYP51C and the remaining kinase-encoding genes (i.e., Bck1 and Slt2) required for Slt2-MAPK signaling. The expression patterns of all the 19 prochloraz-responsive genes, obtained in our RNA-seq data sets, have been validated by quantitative real-time PCR (qRT-PCR). These lines of evidence in together draw a general portrait of anti-DMI mechanisms for P. italicum species. Intriguingly, some strategies adopted by the present Pi-R were not observed in the previously documented prochloraz-resistant P. digitatum transcrtiptomes. These included simultaneous induction of all major EGR11 isoforms (CYP51A/B/C), over-expression of ERG2 and ERG6 to modulate ergosterol anabolism, and concurrent mobilization of Slt2-MAPK and CaMK signaling processes to overcome fungicide-induced stresses. Conclusions The present findings provided transcriptomic evidence on P. italicum DMI-resistance mechanisms and revealed some diversity in anti-DMI strategies between P. italicum and P. digitatum species, contributing to our knowledge on P. italicum DMI-resistance mechanisms.
Collapse
Affiliation(s)
- Tingfu Zhang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Qianwen Cao
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China
| | - Na Li
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.,Yunnan Higher Education Institutions, College of Life Science and Technology, Honghe University, Mengzi, 661199, China
| | - Deli Liu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.
| | - Yongze Yuan
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, 430079, China.
| |
Collapse
|
20
|
Koch B, Barugahare AA, Lo TL, Huang C, Schittenhelm RB, Powell DR, Beilharz TH, Traven A. A Metabolic Checkpoint for the Yeast-to-Hyphae Developmental Switch Regulated by Endogenous Nitric Oxide Signaling. Cell Rep 2019; 25:2244-2258.e7. [PMID: 30463019 DOI: 10.1016/j.celrep.2018.10.080] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 07/31/2018] [Accepted: 10/22/2018] [Indexed: 12/13/2022] Open
Abstract
The yeast Candida albicans colonizes several sites in the human body and responds to metabolic signals in commensal and pathogenic states. The yeast-to-hyphae transition correlates with virulence, but how metabolic status is integrated with this transition is incompletely understood. We used the putative mitochondrial fission inhibitor mdivi-1 to probe the crosstalk between hyphal signaling and metabolism. Mdivi-1 repressed C. albicans hyphal morphogenesis, but the mechanism was independent of its presumed target, the mitochondrial fission GTPase Dnm1. Instead, mdivi-1 triggered extensive metabolic reprogramming, consistent with metabolic stress, and reduced endogenous nitric oxide (NO) levels. Limiting endogenous NO stabilized the transcriptional repressor Nrg1 and inhibited the yeast-to-hyphae transition. We establish a role for endogenous NO signaling in C. albicans hyphal morphogenesis and suggest that NO regulates a metabolic checkpoint for hyphal growth. Furthermore, identifying NO signaling as an mdivi-1 target could inform its therapeutic applications in human diseases.
Collapse
Affiliation(s)
- Barbara Koch
- Infection and Immunity Program and the Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Adele A Barugahare
- Bioinformatics Platform, Monash University, Clayton, VIC 3800, Australia
| | - Tricia L Lo
- Infection and Immunity Program and the Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Cheng Huang
- Biomedical Proteomics Facility and the Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Ralf B Schittenhelm
- Biomedical Proteomics Facility and the Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - David R Powell
- Bioinformatics Platform, Monash University, Clayton, VIC 3800, Australia
| | - Traude H Beilharz
- Development and Stem Cells Program and the Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Ana Traven
- Infection and Immunity Program and the Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
| |
Collapse
|
21
|
Cotner SE, Dawson KL. New Options in Antifungal Therapy: New Drugs, Inhaled Antifungals, and Management of Resistant Pathogens. CURRENT TREATMENT OPTIONS IN INFECTIOUS DISEASES 2019. [DOI: 10.1007/s40506-019-00208-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
22
|
New diphenylphosphane derivatives of ketoconazole are promising antifungal agents. Sci Rep 2019; 9:16214. [PMID: 31700024 PMCID: PMC6838151 DOI: 10.1038/s41598-019-52525-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 10/18/2019] [Indexed: 12/12/2022] Open
Abstract
Four new derivatives of ketoconazole (Ke) were synthesized: diphenylphosphane (KeP), and phosphane chalcogenides: oxide (KeOP), sulphide (KeSP) and selenide (KeSeP). These compounds proved to be promising antifungal compounds towards Saccharomyces cerevisiae and Candida albicans, especially in synergy with fluconazole. Simulations of docking to the cytochrome P450 14α-demethylase (azoles’ primary molecular target) proved that the new Ke derivatives are capable of inhibiting this enzyme by binding to the active site. Cytotoxicity towards hACSs (human adipose-derived stromal cells) of the individual compounds was studied and the IC50 values were higher than the MIC50 for C. albicans and S. cerevisiae. KeP and KeOP increased the level of the p21 gene transcript but did not change the level of p53 gene transcript, a major regulator of apoptosis, and decreased the mitochondrial membrane potential. Taken together, the results advocate that the new ketoconazole derivatives have a similar mechanism of action and block the lanosterol 14α-demethylase and thus inhibit the production of ergosterol in C. albicans membranes.
Collapse
|
23
|
Antifungal Susceptibility of Candida albicans Isolates at a Tertiary Care Hospital in Bulgaria. Jundishapur J Microbiol 2019. [DOI: 10.5812/jjm.92079] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
|
24
|
Prasad R, Nair R, Banerjee A. Multidrug transporters of Candida species in clinical azole resistance. Fungal Genet Biol 2019; 132:103252. [PMID: 31302289 DOI: 10.1016/j.fgb.2019.103252] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/07/2019] [Accepted: 07/08/2019] [Indexed: 11/30/2022]
Abstract
Over-expression of the human P-glycoprotein (P-gp) in tumor cells is a classic example of an ABC protein serving as a hindrance to effective chemotherapy. The existence of proteins homologous to P-gp in organisms encompassing the entire living kingdom highlights extrusion of drugs as a general mechanism of multidrug resistance. Infections caused by opportunistic human fungal pathogens such as Candida species are very common and has intensified in recent years. The typical hosts, who possess suppressed immune systems due to conditions such as HIV and transplantation surgery etc., are prone to fungal infections. Prolonged chemotherapy induces fungal cells to eventually develop tolerance to most of the antifungals currently in clinical use. Amongst other prominent mechanisms of antifungal resistance such as manipulation of the drug target, rapid efflux achieved through overexpression of multidrug transporters has emerged as a major resistance mechanism for azoles. Herein, the azole-resistant clinical isolates of Candida species utilize a few select efflux pump proteins belonging to the ABC and MFS superfamilies, to deter the toxic accumulation of therapeutic azoles and thus, facilitating cell survival. In this article, we summarize and discuss the clinically relevant mechanisms of azole resistance in Candida albicans and non-albicans Candida (NAC) species, specifically highlighting the role of multidrug efflux proteins in the phenomenon.
Collapse
Affiliation(s)
- Rajendra Prasad
- Amity Institute of Integrative Science and Health and Amity Institute of Biotechnology, Amity University Haryana, Gurgaon, Haryana, India.
| | - Remya Nair
- Amity Institute of Integrative Science and Health and Amity Institute of Biotechnology, Amity University Haryana, Gurgaon, Haryana, India
| | - Atanu Banerjee
- Amity Institute of Integrative Science and Health and Amity Institute of Biotechnology, Amity University Haryana, Gurgaon, Haryana, India.
| |
Collapse
|
25
|
Xu J, Liu R, Sun F, An L, Shang Z, Kong L, Yang M. Eucalyptal D Enhances the Antifungal Effect of Fluconazole on Fluconazole-Resistant Candida albicans by Competitively Inhibiting Efflux Pump. Front Cell Infect Microbiol 2019; 9:211. [PMID: 31281800 PMCID: PMC6595430 DOI: 10.3389/fcimb.2019.00211] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 05/31/2019] [Indexed: 12/29/2022] Open
Abstract
The frequent emergence of azole-resistant strains has increasingly led azoles to fail in treating candidiasis. Combination with other drugs is a good option to effectively reduce or retard its incidence of resistance. Natural products are a promising synergist source to assist azoles in treating resistant candidiasis. Eucalyptal D (ED), a formyl-phloroglucinol meroterpenoid, is one of the natural synergists, which could significantly enhance the anticandidal activity of fluconazole (FLC) in treating FLC resistant C. albicans. The checkerboard microdilution assay showed their synergistic effect. The agar disk diffusion test illustrated the key role of ED in synergy. The rhodamine 6G (R6G) efflux assay reflected ED could reduce drug efflux, but quantitative reverse transcription PCR analysis revealed the upregulation of CDR1 and CDR2 genes in ED treating group. Efflux pump-deficient strains were hyper-susceptible to ED, thus ED was speculated to be the substrate of efflux pump Cdr1p and Cdr2p to competitively inhibit the excretion of FLC or R6G, which mainly contributed to its synergistic effect.
Collapse
Affiliation(s)
- Jiali Xu
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, China
| | - Ruihuan Liu
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, China
| | - Fujuan Sun
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, China
| | - Lin An
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, China
| | - Zhichun Shang
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, China
| | - Lingyi Kong
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, China
| | - Minghua Yang
- State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, China Pharmaceutical University, Nanjing, China
| |
Collapse
|
26
|
In Vitro Activities of the Novel Investigational Tetrazoles VT-1161 and VT-1598 Compared to the Triazole Antifungals against Azole-Resistant Strains and Clinical Isolates of Candida albicans. Antimicrob Agents Chemother 2019; 63:AAC.00341-19. [PMID: 30910896 DOI: 10.1128/aac.00341-19] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 03/16/2019] [Indexed: 01/10/2023] Open
Abstract
The fungal Cyp51-specific inhibitors VT-1161 and VT-1598 have emerged as promising new therapies to combat fungal infections, including Candida spp. To evaluate their in vitro activities compared to other azoles, MICs were determined by Clinical and Laboratory Standards Institute (CLSI) method for VT-1161, VT-1598, fluconazole, voriconazole, itraconazole, and posaconazole against 68 C. albicans clinical isolates well characterized for azole resistance mechanisms and mutant strains representing individual azole resistance mechanisms. VT-1161 and VT-1598 demonstrated potent activity (geometric mean MICs ≤0.15 μg/ml) against predominantly fluconazole-resistant (≥8 μg/ml) isolates. However, five of 68 isolates exhibited MICs greater than six dilutions (>2 μg/ml) to both tetrazoles compared to fluconazole-susceptible isolates. Four of these isolates likewise exhibited high MICs beyond the upper limit of the assay for all triazoles tested. A premature stop codon in ERG3 likely explained the high-level resistance in one isolate. VT-1598 was effective against strains with hyperactive Tac1, Mrr1, and Upc2 transcription factors and against most ERG11 mutant strains. VT-1161 MICs were elevated compared to the control strain SC5314 for hyperactive Tac1 strains and two strains with Erg11 substitutions (Y132F and Y132F&K143R) but showed activity against hyperactive Mrr1 and Upc2 strains. While mutations affecting Erg3 activity appear to greatly reduce susceptibility to VT-1161 and VT-1598, the elevated MICs of both tetrazoles for four isolates could not be explained by known azole resistance mechanisms, suggesting the presence of undescribed resistance mechanisms to triazole- and tetrazole-based sterol demethylase inhibitors.
Collapse
|
27
|
The Evolution of Azole Resistance in Candida albicans Sterol 14α-Demethylase (CYP51) through Incremental Amino Acid Substitutions. Antimicrob Agents Chemother 2019; 63:AAC.02586-18. [PMID: 30783005 PMCID: PMC6496074 DOI: 10.1128/aac.02586-18] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 02/10/2019] [Indexed: 12/13/2022] Open
Abstract
Recombinant Candida albicans CYP51 (CaCYP51) proteins containing 23 single and 5 double amino acid substitutions found in clinical strains and the wild-type enzyme were expressed in Escherichia coli and purified by Ni2+-nitrilotriacetic acid agarose chromatography. Catalytic tolerance to azole antifungals was assessed by determination of the concentration causing 50% enzyme inhibition (IC50) using CYP51 reconstitution assays. The greatest increase in the IC50 compared to that of the wild-type enzyme was observed with the five double substitutions Y132F+K143R (15.3-fold), Y132H+K143R (22.1-fold), Y132F+F145L (10.1-fold), G307S+G450E (13-fold), and D278N+G464S (3.3-fold). The single substitutions K143R, D278N, S279F, S405F, G448E, and G450E conferred at least 2-fold increases in the fluconazole IC50, and the Y132F, F145L, Y257H, Y447H, V456I, G464S, R467K, and I471T substitutions conferred increased residual CYP51 activity at high fluconazole concentrations. In vitro testing of select CaCYP51 mutations in C. albicans showed that the Y132F, Y132H, K143R, F145L, S405F, G448E, G450E, G464S, Y132F+K143R, Y132F+F145L, and D278N+G464S substitutions conferred at least a 2-fold increase in the fluconazole MIC. The catalytic tolerance of the purified proteins to voriconazole, itraconazole, and posaconazole was far lower and limited to increased residual activities at high triazole concentrations for certain mutations rather than large increases in IC50 values. Itraconazole was the most effective at inhibiting CaCYP51. However, when tested against CaCYP51 mutant strains, posaconazole seemed to be the most resistant to changes in MIC as a result of CYP51 mutation compared to itraconazole, voriconazole, or fluconazole.
Collapse
|
28
|
Espinel-Ingroff A, Sanguinetti M, Posteraro B. Usefulness of Antifungal Reference In Vitro Susceptibility Tests as a Guide in Therapeutic Management. CURRENT FUNGAL INFECTION REPORTS 2019. [DOI: 10.1007/s12281-019-0336-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
29
|
Can Saccharomyces cerevisiae keep up as a model system in fungal azole susceptibility research? Drug Resist Updat 2019; 42:22-34. [PMID: 30822675 DOI: 10.1016/j.drup.2019.02.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/30/2019] [Accepted: 02/11/2019] [Indexed: 12/14/2022]
Abstract
The difficulty of manipulation and limited availability of genetic tools for use in many pathogenic fungi hamper fast and adequate investigation of cellular metabolism and consequent possibilities for antifungal therapies. S. cerevisiae is a model organism that is used to study many eukaryotic systems. In this review, we analyse the potency and relevance of this model system in investigating fungal susceptibility to azole drugs. Although many of the concepts apply to multiple pathogenic fungi, for the sake of simplicity, we will focus on the validity of using S. cerevisiae as a model organism for two Candida species, C. albicans and C. glabrata. Apart from the general benefits, we explore how S. cerevisiae can specifically be used to improve our knowledge on azole drug resistance and enables fast and efficient screening for novel drug targets in combinatorial therapy. We consider the shortcomings of the model system, yet conclude that it is still opportune to use S. cerevisiae as a model system for pathogenic fungi in this era.
Collapse
|
30
|
Method-Dependent Epidemiological Cutoff Values for Detection of Triazole Resistance in Candida and Aspergillus Species for the Sensititre YeastOne Colorimetric Broth and Etest Agar Diffusion Methods. Antimicrob Agents Chemother 2018; 63:AAC.01651-18. [PMID: 30323038 DOI: 10.1128/aac.01651-18] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 10/03/2018] [Indexed: 11/20/2022] Open
Abstract
Although the Sensititre Yeast-One (SYO) and Etest methods are widely utilized, interpretive criteria are not available for triazole susceptibility testing of Candida or Aspergillus species. We collected fluconazole, itraconazole, posaconazole, and voriconazole SYO and Etest MICs from 39 laboratories representing all continents for (method/agent-dependent) 11,171 Candida albicans, 215 C. dubliniensis, 4,418 C. glabrata species complex, 157 C. guilliermondii (Meyerozyma guilliermondii), 676 C. krusei (Pichia kudriavzevii), 298 C. lusitaniae (Clavispora lusitaniae), 911 C. parapsilosis sensu stricto, 3,691 C. parapsilosis species complex, 36 C. metapsilosis, 110 C. orthopsilosis, 1,854 C. tropicalis, 244 Saccharomyces cerevisiae, 1,409 Aspergillus fumigatus, 389 A. flavus, 130 A. nidulans, 233 A. niger, and 302 A. terreus complex isolates. SYO/Etest MICs for 282 confirmed non-wild-type (non-WT) isolates were included: ERG11 (C. albicans), ERG11 and MRR1 (C. parapsilosis), cyp51A (A. fumigatus), and CDR2 and CDR1 overexpression (C. albicans and C. glabrata, respectively). Interlaboratory modal agreement was superior by SYO for yeast species and by the Etest for Aspergillus spp. Distributions fulfilling CLSI criteria for epidemiological cutoff value (ECV) definition were pooled, and we proposed SYO ECVs for S. cerevisiae and 9 yeast and 3 Aspergillus species and Etest ECVs for 5 yeast and 4 Aspergillus species. The posaconazole SYO ECV of 0.06 µg/ml for C. albicans and the Etest itraconazole ECV of 2 µg/ml for A. fumigatus were the best predictors of non-WT isolates. These findings support the need for method-dependent ECVs, as, overall, the SYO appears to perform better for susceptibility testing of yeast species and the Etest appears to perform better for susceptibility testing of Aspergillus spp. Further evaluations should be conducted with more Candida mutants.
Collapse
|
31
|
Fan X, Xiao M, Zhang D, Huang JJ, Wang H, Hou X, Zhang L, Kong F, Chen SCA, Tong ZH, Xu YC. Molecular mechanisms of azole resistance in Candida tropicalis isolates causing invasive candidiasis in China. Clin Microbiol Infect 2018; 25:885-891. [PMID: 30472420 DOI: 10.1016/j.cmi.2018.11.007] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 11/01/2018] [Accepted: 11/03/2018] [Indexed: 02/06/2023]
Abstract
OBJECTIVE We investigated molecular mechanisms responsible for azole resistance in Candida tropicalis isolates. METHODS We studied 507 C. tropicalis isolates causing invasive candidiasis from ten hospitals over 5 years. Antifungal susceptibility was determined by broth microdilution methods. Point mutations in the C. tropicalis ERG11 gene that may confer azole resistance were explored and verified. The expression levels of ERG11, CYTb, MDR1 and CDR1 genes were compared in 20 fluconazole-susceptible and 20 fluconazole-resistant isolates. RESULTS Fluconazole-susceptible, -susceptible dose-dependent and -resistant strains accounted for 76.7% (389/507), 10.5% (53/507) and 12.8% (65/507) of C. tropicalis isolates, respectively. The ERG11 mutation A395T/W occurred in 10.7% (54/507) of isolates, all of which were resistant to fluconazole. The nucleotide mutation C461T/Y was the second most common (50/507 isolates, 9.9%), and all isolates carrying C461T/Y also had the mutation A395T/W. However, the presence of C461T did not contribute to the azole-resistant phenotype. Substitutions V125A, Y257H and G464S (<2% of isolates), which were reported for the first time in C. tropicalis, also conferred fluconazole non-susceptible phenotypes. Compared with fluconazole susceptible isolates, fluconazole-resistant isolates had higher ERG11 (fold expression level 1.42 versus 0.79, p < 0.01) but lower CYTb (fold expression level 1.26 versus 2.67, p < 0.01) gene expression levels. Three azole-resistant isolates carrying the wild-type ERG11 gene had higher levels of CDR1 and MDR1 expression. CONCLUSIONS ERG11 missense mutations were the major mechanism responsible for azole resistance in C. tropicalis isolates, but overexpression of ERG11, CDR1 and MDR1, as well as reduced expression of CYTb, also contributed to resistance.
Collapse
Affiliation(s)
- X Fan
- Department of Infectious Diseases and Clinical Microbiology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China; Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China; Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - M Xiao
- Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China; Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - D Zhang
- Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China; Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - J-J Huang
- Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China; Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - H Wang
- Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China; Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - X Hou
- Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China; Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - L Zhang
- Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China; Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China
| | - F Kong
- Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, The University of Sydney, Australia
| | - S C-A Chen
- Centre for Infectious Diseases and Microbiology Laboratory Services, ICPMR, New South Wales Health Pathology, Westmead Hospital, The University of Sydney, Australia
| | - Z-H Tong
- Department of Respiratory and Critical Care Medicine, Beijing Institute of Respiratory Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
| | - Y-C Xu
- Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China; Beijing Key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases, Beijing, China.
| |
Collapse
|
32
|
Garcia-Vidal C. [Current therapeutic options in invasive mycosis and potential therapeutic role of isavuconazole]. Rev Iberoam Micol 2018; 35:192-197. [PMID: 30455108 DOI: 10.1016/j.riam.2018.07.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 06/19/2018] [Accepted: 07/19/2018] [Indexed: 01/01/2023] Open
Abstract
The treatment of invasive fungal infections has deeply evolved in recent years with the inclusion of new antifungals to the therapeutic treatment arsenal. A new azole, isavuconazole, has been recently approved. This review focuses on the role of isavuconazole for treating the most important invasive fungal infections: invasive candidiasis, aspergillosis, mucormicosis, infections caused by other filamentous fungi and those caused by dimorphic fungi.
Collapse
Affiliation(s)
- Carolina Garcia-Vidal
- Servicio de Enfermedades Infecciosas, Hospital Clínic de Barcelona-IDIBAPS; Universitat de Barcelona, FungiCLINIC Research group (AGAUR), Barcelona, España.
| |
Collapse
|
33
|
Denis J, Ledoux MP, Nivoix Y, Herbrecht R. Isavuconazole: A new broad-spectrum azole. Part 1: In vitro activity. J Mycol Med 2018. [DOI: 10.1016/j.mycmed.2018.02.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
34
|
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
|
35
|
Pyrpasopoulou A, Iosifidis E, Roilides E. Current and potential treatment options for invasiveCandidainfections. Expert Opin Orphan Drugs 2017. [DOI: 10.1080/21678707.2017.1379392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- A. Pyrpasopoulou
- Infectious Diseases Unit, 3rd Department of Paediatrics, Aristotle University School of Health Sciences, Thessaloniki, Greece
- 2nd Department of Propedeutic Internal Medicine, Faculty of Medicine, Aristotle University School of Health Sciences, Thessaloniki, Greece
| | - E. Iosifidis
- Infectious Diseases Unit, 3rd Department of Paediatrics, Aristotle University School of Health Sciences, Thessaloniki, Greece
| | - E. Roilides
- Infectious Diseases Unit, 3rd Department of Paediatrics, Aristotle University School of Health Sciences, Thessaloniki, Greece
| |
Collapse
|
36
|
Isavuconazole: Has It Saved Us? A Pharmacotherapy Review and Update on Clinical Experience. CURRENT TREATMENT OPTIONS IN INFECTIOUS DISEASES 2017. [DOI: 10.1007/s40506-017-0133-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
37
|
Paulone S, Ardizzoni A, Tavanti A, Piccinelli S, Rizzato C, Lupetti A, Colombari B, Pericolini E, Polonelli L, Magliani W, Conti S, Posteraro B, Cermelli C, Blasi E, Peppoloni S. The synthetic killer peptide KP impairs Candida albicans biofilm in vitro. PLoS One 2017; 12:e0181278. [PMID: 28704490 PMCID: PMC5509322 DOI: 10.1371/journal.pone.0181278] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 06/28/2017] [Indexed: 01/04/2023] Open
Abstract
Candida albicans is a commensal organism, commonly inhabiting mucosal surfaces of healthy individuals, as a part of the resident microbiota. However, in susceptible hosts, especially hospitalized and/or immunocompromised patients, it may cause a wide range of infections. The presence of abiotic substrates, such as central venous or urinary catheters, provides an additional niche for Candida attachment and persistence, particularly via biofilm development. Furthermore, Candida biofilm is poorly susceptible to most antifungals, including azoles. Here we investigated the effects of a synthetic killer peptide (KP), known to be active in vitro, ex vivo and/or in vivo against different pathogens, on C. albicans biofilm. Together with a scrambled peptide used as a negative control, KP was tested against Candida biofilm at different stages of development. A reference strain, two fluconazole-resistant and two fluconazole-susceptible C. albicans clinical isolates were used. KP-induced C. albicans oxidative stress response and membrane permeability were also analysed. Moreover, the effect of KP on transcriptional profiles of C. albicans genes involved in different stages of biofilm development, such as cell adhesion, hyphal development and extracellular matrix production, was evaluated. Our results clearly show that the treatment with KP strongly affected the capacity of C. albicans to form biofilm and significantly impairs preformed mature biofilm. KP treatment resulted in an increase in C. albicans oxidative stress response and membrane permeability; also, biofilm-related genes expression was significantly reduced. Comparable inhibitory effects were observed in all the strains employed, irrespective of their resistance or susceptibility to fluconazole. Finally, KP-mediated inhibitory effects were observed also against a catheter-associated C. albicans biofilm. This study provides the first evidence on the KP effectiveness against C. albicans biofilm, suggesting that KP may be considered as a potential novel tool for treatment and prevention of biofilm-related C. albicans infections.
Collapse
Affiliation(s)
- Simona Paulone
- Department of Diagnostics, Clinical and Public Health Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Andrea Ardizzoni
- Department of Diagnostics, Clinical and Public Health Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | | | - Serena Piccinelli
- Department of Diagnostics, Clinical and Public Health Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Cosmeri Rizzato
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Antonella Lupetti
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Bruna Colombari
- Department of Diagnostics, Clinical and Public Health Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Eva Pericolini
- Department of Diagnostics, Clinical and Public Health Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Luciano Polonelli
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Walter Magliani
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Stefania Conti
- Department of Medicine and Surgery, University of Parma, Parma, Italy
| | - Brunella Posteraro
- Institute of Public Health, Università Cattolica del Sacro Cuore, Fondazione Policlinico Universitario Agostino Gemelli, Rome, Italy
| | - Claudio Cermelli
- Department of Diagnostics, Clinical and Public Health Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | - Elisabetta Blasi
- Department of Diagnostics, Clinical and Public Health Medicine, University of Modena and Reggio Emilia, Modena, Italy
- * E-mail:
| | - Samuele Peppoloni
- Department of Diagnostics, Clinical and Public Health Medicine, University of Modena and Reggio Emilia, Modena, Italy
| |
Collapse
|
38
|
|
39
|
Victoria Castelli M, Gabriel Derita M, Noelí López S. Novel antifungal agents: a patent review (2013 - present). Expert Opin Ther Pat 2016; 27:415-426. [DOI: 10.1080/13543776.2017.1261113] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- María Victoria Castelli
- Universidad Nacional de Rosario, CONICET, Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Rosario, Santa Fe, Argentina
| | - Marcos Gabriel Derita
- Universidad Nacional de Rosario, CONICET, Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Rosario, Santa Fe, Argentina
- Universidad Nacional del Litoral, CONICET, Cátedra de Cultivos Intensivos, Facultad de Ciencias Agrarias, Esperanza, Santa Fe, Argentina
| | - Silvia Noelí López
- Universidad Nacional de Rosario, CONICET, Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Rosario, Santa Fe, Argentina
| |
Collapse
|
40
|
Murrell D, Bossaer JB, Carico R, Harirforoosh S, Cluck D. Isavuconazonium sulfate: a triazole prodrug for invasive fungal infections. INTERNATIONAL JOURNAL OF PHARMACY PRACTICE 2016; 25:18-30. [DOI: 10.1111/ijpp.12302] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Accepted: 07/27/2016] [Indexed: 01/03/2023]
Affiliation(s)
- Derek Murrell
- Department of Pharmaceutical Sciences; Gatton College of Pharmacy; East Tennessee State University; Johnson City TN
| | - John B. Bossaer
- Department of Pharmacy Practice; Gatton College of Pharmacy; East Tennessee State University; Johnson City TN
| | - Ronald Carico
- Department of Pharmacy Practice; Gatton College of Pharmacy; East Tennessee State University; Johnson City TN
| | - Sam Harirforoosh
- Department of Pharmaceutical Sciences; Gatton College of Pharmacy; East Tennessee State University; Johnson City TN
| | - David Cluck
- Department of Pharmacy Practice; Gatton College of Pharmacy; East Tennessee State University; Johnson City TN
| |
Collapse
|
41
|
Wilson DT, Dimondi VP, Johnson SW, Jones TM, Drew RH. Role of isavuconazole in the treatment of invasive fungal infections. Ther Clin Risk Manag 2016; 12:1197-206. [PMID: 27536124 PMCID: PMC4977098 DOI: 10.2147/tcrm.s90335] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Despite recent advances in both diagnosis and prevention, the incidence of invasive fungal infections continues to rise. Available antifungal agents to treat invasive fungal infections include polyenes, triazoles, and echinocandins. Unfortunately, individual agents within each class may be limited by spectrum of activity, resistance, lack of oral formulations, significant adverse event profiles, substantial drug–drug interactions, and/or variable pharmacokinetic profiles. Isavuconazole, a second-generation triazole, was approved by the US Food and Drug Administration in March 2015 and the European Medicines Agency in July 2015 for the treatment of adults with invasive aspergillosis (IA) or mucormycosis. Similar to amphotericin B and posaconazole, isavuconazole exhibits a broad spectrum of in vitro activity against yeasts, dimorphic fungi, and molds. Isavuconazole is available in both oral and intravenous formulations, exhibits a favorable safety profile (notably the absence of QTc prolongation), and reduced drug–drug interactions (relative to voriconazole). Phase 3 studies have evaluated the efficacy of isavuconazole in the management of IA, mucormycosis, and invasive candidiasis. Based on the results of these studies, isavuconazole appears to be a viable treatment option for patients with IA as well as those patients with mucormycosis who are not able to tolerate or fail amphotericin B or posaconazole therapy. In contrast, evidence of isavuconazole for invasive candidiasis (relative to comparator agents such as echinocandins) is not as robust. Therefore, isavuconazole use for invasive candidiasis may initially be reserved as a step-down oral option in those patients who cannot receive other azoles due to tolerability or spectrum of activity limitations. Post-marketing surveillance of isavuconazole will be important to better understand the safety and efficacy of this agent, as well as to better define the need for isavuconazole serum concentration monitoring.
Collapse
Affiliation(s)
- Dustin T Wilson
- Department of Pharmacy Practice, Campbell University College of Pharmacy & Health Sciences, Buies Creek, NC, USA; Department of Pharmacy, Duke University Hospital, Durham, NC, USA
| | - V Paul Dimondi
- Department of Pharmacy Practice, Campbell University College of Pharmacy & Health Sciences, Buies Creek, NC, USA; Department of Pharmacy, Durham VA Medical Center, Durham, NC, USA
| | - Steven W Johnson
- Department of Pharmacy Practice, Campbell University College of Pharmacy & Health Sciences, Buies Creek, NC, USA; Department of Pharmacy, Forsyth Medical Center, Winston-Salem, NC, USA
| | - Travis M Jones
- Department of Pharmacy Practice, Campbell University College of Pharmacy & Health Sciences, Buies Creek, NC, USA
| | - Richard H Drew
- Department of Pharmacy Practice, Campbell University College of Pharmacy & Health Sciences, Buies Creek, NC, USA; Division of Infectious Diseases, Duke University Hospital, Durham, NC, USA
| |
Collapse
|
42
|
Kovanda LL, Maher R, Hope WW. Isavuconazonium sulfate: a new agent for the treatment of invasive aspergillosis and invasive mucormycosis. Expert Rev Clin Pharmacol 2016; 9:887-97. [DOI: 10.1080/17512433.2016.1185361] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Laura L. Kovanda
- Astellas Pharma Global Development, Inc., Northbrook, IL, USA
- Antimicrobial Pharmacodynamics and Therapeutics, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Rochelle Maher
- Astellas Pharma Global Development, Inc., Northbrook, IL, USA
| | - William W. Hope
- Antimicrobial Pharmacodynamics and Therapeutics, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| |
Collapse
|
43
|
Sanglard D. Emerging Threats in Antifungal-Resistant Fungal Pathogens. Front Med (Lausanne) 2016; 3:11. [PMID: 27014694 PMCID: PMC4791369 DOI: 10.3389/fmed.2016.00011] [Citation(s) in RCA: 233] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 03/03/2016] [Indexed: 12/15/2022] Open
Abstract
The use of antifungal drugs in the therapy of fungal diseases can lead to the development of antifungal resistance. Resistance has been described for virtually all antifungal agents in diverse pathogens, including Candida and Aspergillus species. The majority of resistance mechanisms have also been elucidated at the molecular level in these pathogens. Drug resistance genes and genome mutations have been identified. Therapeutic choices are limited for the control of fungal diseases, and it is tempting to combine several drugs to achieve better therapeutic efficacy. In the recent years, several novel resistance patterns have been observed, including antifungal resistance originating from environmental sources in Aspergillus fumigatus and the emergence of simultaneous resistance to different antifungal classes (multidrug resistance) in different Candida species. This review will summarize these current trends.
Collapse
Affiliation(s)
- Dominique Sanglard
- Institute of Microbiology, University Hospital Center, University of Lausanne , Lausanne , Switzerland
| |
Collapse
|