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Delcourte L, Berbon M, Rodriguez M, Subban K, Lends A, Grélard A, Morvan E, Habenstein B, Saupe SJ, Delhaes L, Aimanianda V, Daskalov A, Loquet A. Magic-angle spinning NMR spectral editing of polysaccharides in whole cells using the DREAM scheme. Methods 2024; 230:59-67. [PMID: 39047926 DOI: 10.1016/j.ymeth.2024.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2024] [Revised: 07/12/2024] [Accepted: 07/15/2024] [Indexed: 07/27/2024] Open
Abstract
Most bacterial, plant and fungal cells possess at their surface a protective layer called the cell wall, conferring strength, plasticity and rigidity to withstand the osmotic pressure. This molecular barrier is crucial for pathogenic microorganisms, as it protects the cell from the local environment and often constitutes the first structural component encountered in the host-pathogen interaction. In pathogenic molds and yeasts, the cell wall constitutes the main target for the development of clinically-relevant antifungal drugs. In the past decade, solid-state NMR has emerged as a powerful analytical technique to investigate the molecular organization of microbial cell walls in the context of intact cells. 13C NMR chemical shift is an exquisite source of information to identify the polysaccharides present in the cell wall, and two-dimensional 13C-13C correlation experiments provide an efficient tool to rapidly access the polysaccharide composition in whole cells. Here we investigate the use of the adiabatic DREAM (for dipolar recoupling enhancement through amplitude modulation) recoupling scheme to improve solid-state NMR analysis of polysaccharides in intact cells. We demonstrate the advantages of two-dimensional 13C-13C experiments using the DREAM recoupling scheme. We report the spectral editing of polysaccharide signals by varying the radio-frequency carrier position. We provide practical considerations for the implementation of DREAM experiments to characterize polysaccharides in whole cells. We demonstrate the approach on intact fungal cells of Neurospora crassa and Aspergillus fumigatus, a model and a pathogenic filamentous fungus, respectively. The approach could be envisioned to efficiently reduce the spectral crowding of more complex cell surfaces, such as cell wall and peptidoglycan in bacteria.
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Affiliation(s)
- Loic Delcourte
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Mélanie Berbon
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Marion Rodriguez
- CNR des Aspergilloses Chroniques, Mycology-Parasitology Department, CHU Bordeaux, Bordeaux 33000, France
| | - Kamalraj Subban
- ImmunoConcEpT, CNRS, UMR 5164, University of Bordeaux, Bordeaux, France
| | - Alons Lends
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Axelle Grélard
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Estelle Morvan
- Univ. Bordeaux, CNRS, Inserm, IECB, UAR3033, US01, Pessac, France
| | - Birgit Habenstein
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France
| | - Sven J Saupe
- CNRS, Université de Bordeaux, IBGC, UMR 5095, Bordeaux, France
| | - Laurence Delhaes
- CNR des Aspergilloses Chroniques, Mycology-Parasitology Department, CHU Bordeaux, Bordeaux 33000, France; Centre de Recherche Cardio-Thoracique de Bordeaux, Inserm UMR 1045, Univ Bordeaux, Bordeaux 33000, France
| | - Vishukumar Aimanianda
- Institut Pasteur, Université Paris Cité, Immunobiology of Aspergillus, Mycology Department, Paris, France
| | - Asen Daskalov
- ImmunoConcEpT, CNRS, UMR 5164, University of Bordeaux, Bordeaux, France; State Key Laboratory for Managing Biotic and Chemical Treats to the Quality and Safety of Agro-products, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Antoine Loquet
- Univ. Bordeaux, CNRS, Bordeaux INP, CBMN, UMR 5248, IECB, Pessac, France.
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Puumala E, Fallah S, Robbins N, Cowen LE. Advancements and challenges in antifungal therapeutic development. Clin Microbiol Rev 2024; 37:e0014223. [PMID: 38294218 PMCID: PMC10938895 DOI: 10.1128/cmr.00142-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024] Open
Abstract
Over recent decades, the global burden of fungal disease has expanded dramatically. It is estimated that fungal disease kills approximately 1.5 million individuals annually; however, the true worldwide burden of fungal infection is thought to be higher due to existing gaps in diagnostics and clinical understanding of mycotic disease. The development of resistance to antifungals across diverse pathogenic fungal genera is an increasingly common and devastating phenomenon due to the dearth of available antifungal classes. These factors necessitate a coordinated response by researchers, clinicians, public health agencies, and the pharmaceutical industry to develop new antifungal strategies, as the burden of fungal disease continues to grow. This review provides a comprehensive overview of the new antifungal therapeutics currently in clinical trials, highlighting their spectra of activity and progress toward clinical implementation. We also profile up-and-coming intracellular proteins and pathways primed for the development of novel antifungals targeting their activity. Ultimately, we aim to emphasize the importance of increased investment into antifungal therapeutics in the current continually evolving landscape of infectious disease.
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Affiliation(s)
- Emily Puumala
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Sara Fallah
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Leah E. Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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3
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Sass G, Larwood DJ, Stevens DA. Synergy In Vitro of Nikkomycin Z with Azole Against the Invasive Form of Candida albicans. Mycopathologia 2023; 188:949-956. [PMID: 37713047 DOI: 10.1007/s11046-023-00788-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 08/18/2023] [Indexed: 09/16/2023]
Abstract
In a previous study, therapeutic activity of nikkomycin Z (NZ) in a model of invasive candidiasis did not appear to correlate with lesser activity in vitro (using classical MIC methods) with planktonic organisms. However, NZ potency was much greater assaying activity in vitro against germ tubes, the initiator of the invasive mycelial form of the fungus, as occurs in infected tissues. Synergy has been demonstrated for NZ and other drugs, notably fluconazole (the most commonly used drug against candidiasis), in planktonic testing, which correlated with results in vivo. This raised the question whether activity shown by NZ alone against germ tubes would be reflected in drug combinations, and even whether synergy testing against germ tubes might be a better correlate of synergy in future in vivo studies. We show in this study significant NZ synergy with fluconazole against germ tubes, for several C. albicans isolates, with testing in many drug ratios. This observation opens the way for further explorations of this method of susceptibility testing for synergy, and correlation with combination therapy against candidiasis.
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Affiliation(s)
- Gabriele Sass
- California Institute for Medical Research, San Jose, CA, USA.
| | - David J Larwood
- California Institute for Medical Research, San Jose, CA, USA
- Valley Fever Solutions, Tucson, AZ, USA
| | - David A Stevens
- California Institute for Medical Research, San Jose, CA, USA
- Division of Infectious Diseases and Geographic Medicine, Stanford University Medical School, Stanford, CA, USA
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De Bels D, Maillart E, Van Bambeke F, Redant S, Honoré PM. Existing and emerging therapies for the treatment of invasive candidiasis and candidemia. Expert Opin Emerg Drugs 2022; 27:405-416. [PMID: 36317695 DOI: 10.1080/14728214.2022.2142207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
INTRODUCTION Invasive candidiasis or candidemia is a severe infection affecting more than 250,000 people worldwide every year. It is present in up to 16% of ICU patients. The prognosis of these infections is unfavorable, with global death estimated around 50,000 per year, which corresponds to up to 40% depending on patient severity and comorbidities. Therapeutic failure is not rare due to the emergence of multiresistant strains and of new species poorly responsive to current therapies like Candida auris. AREAS COVERED We first review the positioning of antifungal drugs used to treat candidiasis, namely polyenes, azoles, echinocandins and pyrimidine analogues. We then discuss the progresses brought by new formulations, new derivatives within these classes, compounds acting on new targets or repurposed drugs in terms of pharmacokinetic profile, spectrum of activity, potency, safety or risk of drug-drug interactions. EXPERT OPINION While new formulations (amphotericin B cochleate) improve oral bioavailability of the corresponding drugs, new azoles or echinocandins offer higher potency including against strains resistant to former generations of drugs. Repurposed drugs show synergism with current therapies in vitro. Results from ongoing and future clinical trials will be decisive to establish the interest for these drugs in our arsenal.
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Affiliation(s)
- David De Bels
- Intensive Care Department, Brugmann University Hospital, Brussels, Belgium
| | - Evelyne Maillart
- Department of Infectious Disease, Brugmann University Hospital, Brussels, Belgium
| | - Françoise Van Bambeke
- Louvain Drug Research Institute, Department of Pharmacology, Université Catholique de Louvain, Brussels, Belgium
| | - Sebastien Redant
- Intensive Care Department, Brugmann University Hospital, Brussels, Belgium
| | - Patrick M Honoré
- Intensive Care Department, Brugmann University Hospital, Brussels, Belgium.,Faculty of Medicine, Université Libre de Bruxelles, Brussels, Belgium.,Department of ICU, CHU UCL Godinne-Namur, UCL Louvain Medical School
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Ahmadipour S, Field RA, Miller GJ. Prospects for anti- Candida therapy through targeting the cell wall: A mini-review. Cell Surf 2021; 7:100063. [PMID: 34746525 PMCID: PMC8551693 DOI: 10.1016/j.tcsw.2021.100063] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 09/30/2021] [Accepted: 09/30/2021] [Indexed: 01/08/2023] Open
Abstract
The impact of fungal infections on humans is a serious public health issue that has received much less attention than bacterial infection and treatment, despite ever-increasing incidence exacerbated by an increased incidence of immunocompromised individuals in the population. Candida species, in particular, cause some of the most prevalent hospital-related fungal infections. Fungal infections are also detrimental to the well-being of grazing livestock, with milk production in dairy cows, and body and coat condition adversely affected by fungal infections. Fungal cell walls are essential for viability, morphogenesis and pathogenesis: numerous anti-fungal drugs rely on targeting either the cell wall or cell membrane, but the pipeline of available bioactives is limited. There is a clear and unmet need to identify novel targets and develop new classes of anti-fungal agents. This mini review focuses on fungal cell wall structure, composition and biosynthesis in Candida spp., including C. auris. In addition, an overview of current advances in the development of cell wall targeted therapies is considered.
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Affiliation(s)
- Sanaz Ahmadipour
- Department of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, Manchester M1 7DN, United Kingdom.,Iceni Diagnostics Ltd, The Innovation Centre, Norwich Research Park, Norwich, Norfolk NR4 7GJ, United Kingdom
| | - Robert A Field
- Department of Chemistry and Manchester Institute of Biotechnology, The University of Manchester, Manchester M1 7DN, United Kingdom.,Iceni Diagnostics Ltd, The Innovation Centre, Norwich Research Park, Norwich, Norfolk NR4 7GJ, United Kingdom
| | - Gavin J Miller
- Lennard-Jones Laboratory, School of Chemical and Physical Sciences, Keele University, Keele, Staffordshire ST5 5BG, United Kingdom
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Bentz ML, Nunnally N, Lockhart SR, Sexton DJ, Berkow EL. Antifungal activity of nikkomycin Z against Candida auris. J Antimicrob Chemother 2021; 76:1495-1497. [PMID: 33677578 DOI: 10.1093/jac/dkab052] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 02/03/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Nikkomycin Z is a competitive inhibitor of chitin synthase-an enzyme needed for synthesis of the fungal cell wall. Nikkomycin Z shows promise as a treatment for coccidioidomycoses and mixed activity has been described against other fungi and yeast. To our knowledge, it has not previously been tested against the emerging fungal pathogen Candida auris. OBJECTIVES To determine the in vitro activity of nikkomycin Z against C. auris. METHODS Nikkomycin Z was tested by broth microdilution against a panel of 100 isolates of genetically diverse C. auris from around the world. RESULTS Nikkomycin Z showed mixed activity against the tested isolates, with an MIC range of 0.125 to >64 mg/L. The MIC50 and MIC90 were 2 and 32 mg/L, respectively. CONCLUSIONS These findings suggest nikkomycin Z has in vitro activity against some, but not all isolates of C. auris.
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Affiliation(s)
- Meghan L Bentz
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, 1600 Clifton Rd., Mailstop H17-2, Atlanta, GA30333, USA
| | | | - Shawn R Lockhart
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, 1600 Clifton Rd., Mailstop H17-2, Atlanta, GA30333, USA
| | - D Joseph Sexton
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, 1600 Clifton Rd., Mailstop H17-2, Atlanta, GA30333, USA
| | - Elizabeth L Berkow
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, 1600 Clifton Rd., Mailstop H17-2, Atlanta, GA30333, USA
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McErlean M, Liu X, Cui Z, Gust B, Van Lanen SG. Identification and characterization of enzymes involved in the biosynthesis of pyrimidine nucleoside antibiotics. Nat Prod Rep 2021; 38:1362-1407. [PMID: 33404015 DOI: 10.1039/d0np00064g] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Covering: up to September 2020 Hundreds of nucleoside-based natural products have been isolated from various microorganisms, several of which have been utilized in agriculture as pesticides and herbicides, in medicine as therapeutics for cancer and infectious disease, and as molecular probes to study biological processes. Natural products consisting of structural modifications of each of the canonical nucleosides have been discovered, ranging from simple modifications such as single-step alkylations or acylations to highly elaborate modifications that dramatically alter the nucleoside scaffold and require multiple enzyme-catalyzed reactions. A vast amount of genomic information has been uncovered the past two decades, which has subsequently allowed the first opportunity to interrogate the chemically intriguing enzymatic transformations for the latter type of modifications. This review highlights (i) the discovery and potential applications of structurally complex pyrimidine nucleoside antibiotics for which genetic information is known, (ii) the established reactions that convert the canonical pyrimidine into a new nucleoside scaffold, and (iii) the important tailoring reactions that impart further structural complexity to these molecules.
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Affiliation(s)
- M McErlean
- Department of Pharmaceutical Science, College of Pharmacy, University of Kentucky, USA.
| | - X Liu
- Department of Pharmaceutical Science, College of Pharmacy, University of Kentucky, USA.
| | - Z Cui
- Department of Pharmaceutical Science, College of Pharmacy, University of Kentucky, USA.
| | - B Gust
- Pharmaceutical Institute, Department of Pharmaceutical Biology, University of Tübingen, Germany
| | - S G Van Lanen
- Department of Pharmaceutical Science, College of Pharmacy, University of Kentucky, USA.
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8
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Freitas e Silva KS, C. Silva L, Gonçales RA, Neves BJ, Soares CM, Pereira M. Setting New Routes for Antifungal Drug Discovery Against Pathogenic Fungi. Curr Pharm Des 2020; 26:1509-1520. [DOI: 10.2174/1381612826666200317125956] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 02/11/2020] [Indexed: 01/08/2023]
Abstract
:Fungal diseases are life-threatening to human health and responsible for millions of deaths around the world. Fungal pathogens lead to a high number of morbidity and mortality. Current antifungal treatment comprises drugs, such as azoles, echinocandins, and polyenes and the cure is not guaranteed. In addition, such drugs are related to severe side effects and the treatment lasts for an extended period. Thus, setting new routes for the discovery of effective and safe antifungal drugs should be a priority within the health care system. The discovery of alternative and efficient antifungal drugs showing fewer side effects is time-consuming and remains a challenge. Natural products can be a source of antifungals and used in combinatorial therapy. The most important natural products are antifungal peptides, antifungal lectins, antifungal plants, and fungi secondary metabolites. Several proteins, enzymes, and metabolic pathways could be targets for the discovery of efficient inhibitor compounds and recently, heat shock proteins, calcineurin, salinomycin, the trehalose biosynthetic pathway, and the glyoxylate cycle have been investigated in several fungal species. HSP protein inhibitors and echinocandins have been shown to have a fungicidal effect against azole-resistant fungi strains. Transcriptomic and proteomic approaches have advanced antifungal drug discovery and pointed to new important specific-pathogen targets. Certain enzymes, such as those from the glyoxylate cycle, have been a target of antifungal compounds in several fungi species. Natural and synthetic compounds inhibited the activity of such enzymes and reduced the ability of fungal cells to transit from mycelium to yeast, proving to be promisor antifungal agents. Finally, computational biology has developed effective approaches, setting new routes for early antifungal drug discovery since normal approaches take several years from discovery to clinical use. Thus, the development of new antifungal strategies might reduce the therapeutic time and increase the quality of life of patients.
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Affiliation(s)
- Kleber S. Freitas e Silva
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Lívia C. Silva
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Relber A. Gonçales
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Bruno J. Neves
- LabMol - Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia, Universidade Federal de Goiás, Goiânia, GO, 74605-510, Brazil
| | - Célia M.A. Soares
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Maristela Pereira
- Laboratório de Biologia Molecular, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
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Shi L, Liu B, Wei Q, Ge B, Zhang K. Genome-wide transcriptomic analysis of the response of Botrytis cinerea to wuyiencin. PLoS One 2020; 15:e0224643. [PMID: 32348310 PMCID: PMC7190121 DOI: 10.1371/journal.pone.0224643] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 03/26/2020] [Indexed: 11/19/2022] Open
Abstract
Grey mould is caused by the ascomycetes Botrytis cinerea in a range of crop hosts. As a biological control agent, the nucleoside antibiotic wuyiencin has been industrially produced and widely used as an effective fungicide. To elucidate the effects of wuyiencin on the transcriptional regulation in B. cinerea, we, for the first time, report a genome-wide transcriptomic analysis of B. cinerea treated with wuyiencin. 2067 genes were differentially expressed, of them, 886 and 1181 genes were significantly upregulated and downregulated, respectively. Functional categorization indicated that transcript levels of genes involved in amino acid metabolism and those encoding putative secreted proteins were altered in response to wuyiencin treatment. Moreover, the expression of genes involved in protein synthesis and energy metabolism (oxidative phosphorylation) and of those encoding ATP-binding cassette transporters was markedly upregulated, whereas that of genes participating in DNA replication, cell cycle, and stress response was downregulated. Furthermore, wuyiencin resulted in mycelial malformation and negatively influenced cell growth rate and conidial yield in B. cinerea. Our results suggest that this nucleoside antibiotic regulates all aspects of cell growth and differentiation in B. cinerea. To summarize, some new candidate pathways and target genes that may related to the protective and antagonistic mechanisms in B. cinerea were identified underlying the action of biological control agents.
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Affiliation(s)
- Liming Shi
- State Key Laboratory of Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, PR China
| | - Binghua Liu
- State Key Laboratory of Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, PR China
| | - Qiuhe Wei
- State Key Laboratory of Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, PR China
| | - Beibei Ge
- State Key Laboratory of Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, PR China
- * E-mail: (KZ); (BG)
| | - Kecheng Zhang
- State Key Laboratory of Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, PR China
- * E-mail: (KZ); (BG)
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10
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Tong S, Li M, Keyhani NO, Liu Y, Yuan M, Lin D, Jin D, Li X, Pei Y, Fan Y. Characterization of a fungal competition factor: Production of a conidial cell-wall associated antifungal peptide. PLoS Pathog 2020; 16:e1008518. [PMID: 32324832 PMCID: PMC7200012 DOI: 10.1371/journal.ppat.1008518] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 05/05/2020] [Accepted: 04/05/2020] [Indexed: 01/16/2023] Open
Abstract
Competition is one of the fundamental driving forces of natural selection. Beauveria bassiana is a soil and plant phylloplane/root fungus capable of parasitizing insect hosts. Soil and plant environments are often enriched with other fungi against which B. bassiana competes for survival. Here, we report an antifungal peptide (BbAFP1), specifically expressed and localized to the conidial cell wall and is released into the surrounding microenvironment inhibiting growth of competing fungi. B. bassiana strains expressing BbAFP1, including overexpression strains, inhibited growth of Alternaria brassicae in co-cultured experiments, whereas targeted gene deletion of BbAFP1 significantly decreased (25%) this inhibitory effect. Recombinant BbAFP1 showed chitin and glucan binding abilities, and growth inhibition of a wide range of phytopathogenic fungi by disrupting membrane integrity and eliciting reactive oxygen species (ROS) production. A phenylalanine residue (F50) contributes to chitin binding and antifungal activity, but was not required for the latter. Expression of BbAFP1 in tomato resulted in transgenic plants with enhanced resistance to plant fungal pathogens. These results highlight the importance of fungal competition in shaping primitive competition strategies, with antimicrobial compounds that can be embedded in the spore cell wall to be released into the environment during the critical initial phases of germination for successful growth in its environmental niche. Furthermore, these peptides can be exploited to increase plant resistance to fungal pathogens. Microbial competition exerts powerful selective pressures for the development of defensive and offensive methods of suppressing potential competitors. One of the most vulnerable stages for any fungi is the initial germination of resting spores in potentially hostile environments. Currently, we know little about how fungi defend other microbial competitors during the beginning stage of conidial germination. Here, we report on an antifungal peptide from B. bassiana (BbAFP1) that is specifically expressed in mature aerial conidia, with the protein localized exclusively to the conidial cell wall. The “pre-loaded” BbAFP1 is released into the surrounding microenvironment where it can act to inhibit the growth of competing fungi during the initial stages of fungal germination, i.e. largely before actual germ tubes are apparent, thus conferring an advantage to B. bassiana in out-competing susceptible competitors in the microenvironment surrounding the spore. The effects of BbAFP1 on membrane integrity were characterized and a key amino acid (F50) was shown to function in chitin binding and antifungal activity. Transgenic tomato overexpressing BbAFP1 were shown to exhibit enhanced resistance to plant fungal pathogens. Our study provides new insights into the microbial competition and genes involved in this process that can be exploited to increase plant disease resistance.
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Affiliation(s)
- Sheng Tong
- Biotechnology Research Center, Southwest University, Chongqing, P.R. China
| | - Maolian Li
- Biotechnology Research Center, Southwest University, Chongqing, P.R. China
| | - Nemat O. Keyhani
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida, United States of America
| | - Yu Liu
- College of Biotechnology, Southwest University, Chongqing, P. R. China
| | - Min Yuan
- Biotechnology Research Center, Southwest University, Chongqing, P.R. China
| | - Dongmei Lin
- Biotechnology Research Center, Southwest University, Chongqing, P.R. China
| | - Dan Jin
- Biotechnology Research Center, Southwest University, Chongqing, P.R. China
| | - Xianbi Li
- Biotechnology Research Center, Southwest University, Chongqing, P.R. China
| | - Yan Pei
- Biotechnology Research Center, Southwest University, Chongqing, P.R. China
| | - Yanhua Fan
- Biotechnology Research Center, Southwest University, Chongqing, P.R. China
- Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, Southwest University, Chongqing, P.R. China
- * E-mail:
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11
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Cortés JCG, Curto MÁ, Carvalho VSD, Pérez P, Ribas JC. The fungal cell wall as a target for the development of new antifungal therapies. Biotechnol Adv 2019; 37:107352. [PMID: 30797093 DOI: 10.1016/j.biotechadv.2019.02.008] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 01/23/2019] [Accepted: 02/16/2019] [Indexed: 12/17/2022]
Abstract
In the past three decades invasive mycoses have globally emerged as a persistent source of healthcare-associated infections. The cell wall surrounding the fungal cell opposes the turgor pressure that otherwise could produce cell lysis. Thus, the cell wall is essential for maintaining fungal cell shape and integrity. Given that this structure is absent in host mammalian cells, it stands as an important target when developing selective compounds for the treatment of fungal infections. Consequently, treatment with echinocandins, a family of antifungal agents that specifically inhibits the biosynthesis of cell wall (1-3)β-D-glucan, has been established as an alternative and effective antifungal therapy. However, the existence of many pathogenic fungi resistant to single or multiple antifungal families, together with the limited arsenal of available antifungal compounds, critically affects the effectiveness of treatments against these life-threatening infections. Thus, new antifungal therapies are required. Here we review the fungal cell wall and its relevance in biotechnology as a target for the development of new antifungal compounds, disclosing the most promising cell wall inhibitors that are currently in experimental or clinical development for the treatment of some invasive mycoses.
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Affiliation(s)
- Juan Carlos G Cortés
- Instituto de Biología Funcional y Genómica and Departamento de Microbiología y Genética, Consejo Superior de Investigaciones Científicas (CSIC)/Universidad de Salamanca, Salamanca, Spain.
| | - M-Ángeles Curto
- Instituto de Biología Funcional y Genómica and Departamento de Microbiología y Genética, Consejo Superior de Investigaciones Científicas (CSIC)/Universidad de Salamanca, Salamanca, Spain
| | - Vanessa S D Carvalho
- Instituto de Biología Funcional y Genómica and Departamento de Microbiología y Genética, Consejo Superior de Investigaciones Científicas (CSIC)/Universidad de Salamanca, Salamanca, Spain
| | - Pilar Pérez
- Instituto de Biología Funcional y Genómica and Departamento de Microbiología y Genética, Consejo Superior de Investigaciones Científicas (CSIC)/Universidad de Salamanca, Salamanca, Spain
| | - Juan Carlos Ribas
- Instituto de Biología Funcional y Genómica and Departamento de Microbiología y Genética, Consejo Superior de Investigaciones Científicas (CSIC)/Universidad de Salamanca, Salamanca, Spain.
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12
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Effects of Echinocandins in Combination with Nikkomycin Z against Invasive Candida albicans Bloodstream Isolates and the fks Mutants. Antimicrob Agents Chemother 2017; 61:AAC.00619-17. [PMID: 28827418 PMCID: PMC5655089 DOI: 10.1128/aac.00619-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 08/10/2017] [Indexed: 11/20/2022] Open
Abstract
We evaluated the in vitro and in vivo effects of nikkomycin Z combined with an echinocandin (anidulafungin or micafungin) against two Candida albicans isolates and their lab-derived echinocandin-resistant fks mutants with FKS1 S645Y and FKS1 S645P. Synergistic effects were observed in all tested strains (fractional inhibitory concentration index, <0.5). Enhanced survival was observed in an immunocompromised murine model (log-rank test, P < 0.02). Our study demonstrated the therapeutic potential of nikkomycin Z-echinocandin combinations in managing echinocandin resistance.
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Wong SSW, Samaranayake LP, Seneviratne CJ. In pursuit of the ideal antifungal agent for Candida infections: high-throughput screening of small molecules. Drug Discov Today 2014; 19:1721-1730. [PMID: 24952336 DOI: 10.1016/j.drudis.2014.06.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 05/23/2014] [Accepted: 06/12/2014] [Indexed: 01/22/2023]
Abstract
Candida infections have created a great burden on the public healthcare sector. The situation is worsened by recent epidemiological changes. Furthermore, the current arsenal of antifungal agents is limited and associated with undesirable drawbacks. Therefore, new antifungal agents that surpass the existing ones are urgently needed. High-throughput screening of small molecule libraries enables rapid hit identification and, possibly, increases hit rate. Moreover, the identified hits could be associated with unrecognized or multiple drug targets, which would provide novel insights into the biological processes of the pathogen. Hence, it is proposed that high-throughput screening of small molecules is particularly important in the pursuit of the ideal antifungal agents for Candida infections.
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Affiliation(s)
- Sarah S W Wong
- Faculty of Dentistry, University of Hong Kong, Hong Kong
| | | | - Chaminda J Seneviratne
- Faculty of Dentistry, University of Hong Kong, Hong Kong; Oral Sciences, Faculty of Dentistry, National University of Singapore, Singapore.
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Munro CA. Chitin and glucan, the yin and yang of the fungal cell wall, implications for antifungal drug discovery and therapy. ADVANCES IN APPLIED MICROBIOLOGY 2013; 83:145-72. [PMID: 23651596 DOI: 10.1016/b978-0-12-407678-5.00004-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The structural carbohydrate polymers glucan and chitin compliment and reinforce each other in a dynamic process to maintain the integrity and physical strength of the fungal cell wall. The assembly of chitin and glucan in the cell wall of the budding yeast Saccharomyces cerevisiae and the polymorphic human pathogen Candida albicans are essential processes that involve a range of fungal-specific enzymes and regulatory networks. The fungal cell wall is, therefore, an attractive target for novel therapies as host cells lack many cell wall-related proteins. The most recent class of antifungal drug approved for clinical use, the echinocandins, targets the synthesis of cell wall β(1-3)glucan. The echinocandins are effective at treating invasive and bloodstream Candida infections and are now widely used in the clinic. However, there have been sporadic reports of breakthrough infections in patients undergoing echinocandin therapy. The acquisition of point mutations in the FKS genes that encode the catalytic β(1-3)glucan synthase subunits, the target of the echinocandins, has emerged as a dominant resistance mechanism. Cells with elevated chitin levels are also less susceptible to echinocandins and in addition, treatment with sub-MIC echinocandin activates cell wall salvage pathways that increase chitin synthesis to compensate for reduced glucan production. The development of drugs targeting the cell wall has already proven to be beneficial in providing an alternative class of drug for use in the clinic. Other cell wall targets such as chitin synthesis still hold great potential for drug development but careful consideration should be given to the capacity of fungi to manipulate their walls in a dynamic response to cell wall perturbations.
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Affiliation(s)
- Carol A Munro
- School of Medical Sciences, University of Aberdeen, Aberdeen, UK, E-mail:
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Zhao J, Guo L, Zeng H, Yang X, Yuan J, Shi H, Xiong Y, Chen M, Han L, Qiu D. Purification and characterization of a novel antimicrobial peptide from Brevibacillus laterosporus strain A60. Peptides 2012; 33:206-11. [PMID: 22244810 DOI: 10.1016/j.peptides.2012.01.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2011] [Revised: 01/02/2012] [Accepted: 01/02/2012] [Indexed: 11/25/2022]
Abstract
A novel antimicrobial peptide, with molecular mass of 1602.0469Da, produced by Brevibacillus laterosporus strain A60 was isolated and purified from the soil of mango plants. The purification procedure consisted of ammonium sulfate precipitation, cation exchange chromatography on an HiTrap SP HP column, thin layer chromatography and High Performance Liquid Chromatography (HPLC) on C18 reversed-phase column. After the four isolation procedures, one peptide with antimicrobial activity was obtained and named BL-A60. The determination of the complete amino acid sequences of this peptide showed that it contains eleven amino acid residues, L-Y-K-L-V-K-V-V-L-N-M, and a choline connected to the N-terminal and a tenuazonic acid modified of the C-terminal. This peptide shows relatively low identification to other antimicrobial peptides from bacteria. Purified BL-A60 showed high pH and thermal stability and a strong inhibition of different stages of the life cycle of Phytophthora capsici, including mycelial growth, sporangia formation and cystospore germination, with EC(50) values of 7.89, 0.60 and 21.96 μg ml(-1), respectively.
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Affiliation(s)
- Jing Zhao
- Key Laboratory of Integrated Pest Management in Crops, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, No 12 Zhongguancun South Street, Beijing 100081, China
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Yutani M, Hashimoto Y, Ogita A, Kubo I, Tanaka T, Fujita KI. Morphological Changes of the Filamentous Fungus Mucor Mucedo
and Inhibition of Chitin Synthase Activity Induced by Anethole. Phytother Res 2011; 25:1707-13. [DOI: 10.1002/ptr.3579] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2010] [Revised: 05/11/2011] [Accepted: 05/24/2011] [Indexed: 11/07/2022]
Affiliation(s)
- Masahiro Yutani
- Graduate School of Science; Osaka City University, 3-3-138 Sugimoto; Sumiyoshi-ku Osaka 558-8585 Japan
| | - Yukie Hashimoto
- Graduate School of Science; Osaka City University, 3-3-138 Sugimoto; Sumiyoshi-ku Osaka 558-8585 Japan
| | - Akira Ogita
- Graduate School of Science; Osaka City University, 3-3-138 Sugimoto; Sumiyoshi-ku Osaka 558-8585 Japan
- Research Center for Urban Health and Sports; Osaka City University, 3-3-138 Sugimoto; Sumiyoshi-ku Osaka 558-8585 Japan
| | - Isao Kubo
- Department of Environmental Science, Policy and Management; University of California; Berkeley CA 94720-3114 USA
| | - Toshio Tanaka
- Graduate School of Science; Osaka City University, 3-3-138 Sugimoto; Sumiyoshi-ku Osaka 558-8585 Japan
| | - Ken-ichi Fujita
- Graduate School of Science; Osaka City University, 3-3-138 Sugimoto; Sumiyoshi-ku Osaka 558-8585 Japan
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Tsai PW, Yang CY, Chang HT, Lan CY. Characterizing the role of cell-wall β-1,3-exoglucanase Xog1p in Candida albicans adhesion by the human antimicrobial peptide LL-37. PLoS One 2011; 6:e21394. [PMID: 21713010 PMCID: PMC3119699 DOI: 10.1371/journal.pone.0021394] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Accepted: 05/27/2011] [Indexed: 12/04/2022] Open
Abstract
Candida albicans is the major fungal pathogen of humans. Its adhesion to host-cell surfaces is the first critical step during mucosal infection. Antimicrobial peptides play important roles in the first line of mucosal immunity against C. albicans infection. LL-37 is the only member of the human cathelicidin antimicrobial peptide family and is commonly expressed in various tissues, including epithelium. We previously showed that LL-37 significantly reduced C. albicans adhesion to plastic, oral epidermoid OECM-1 cells, and urinary bladders of female BALB/c mice. The inhibitory effect of LL-37 on cell adhesion occurred via the binding of LL-37 to cell-wall carbohydrates. Here we showed that formation of LL-37–cell-wall protein complexes potentially inhibits C. albicans adhesion to polystyrene. Using phage display and ELISA, we identified 10 peptide sequences that could bind LL-37. A BLAST search revealed that four sequences in the major C. albicans cell-wall β-1,3-exoglucanase, Xog1p, were highly similar to the consensus sequence derived from the 10 biopanned peptides. One Xog1p-derived peptide, Xog1p90–115, and recombinant Xog1p associated with LL-37, thereby reversing the inhibitory effect of LL-37 on C. albicans adhesion. LL-37 reduced Xog1p activity and thus interrupted cell-wall remodeling. Moreover, deletion of XOG1 or another β-1,3-exoglucanase-encoding gene EXG2 showed that only when XOG1 was deleted did cellular exoglucanase activity, cell adhesion and LL-37 binding decrease. Antibodies against Xog1p also decreased cell adhesion. These data reveal that Xog1p, originally identified from LL-37 binding, has a role in C. albicans adhesion to polystyrene and, by inference, attach to host cells via direct or indirect manners. Compounds that target Xog1p might find use as drugs that prevent C. albicans infection. Additionally, LL-37 could potentially be used to screen for other cell-wall components involved in fungal cell adhesion.
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Affiliation(s)
- Pei-Wen Tsai
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
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Ajesh K, Sreejith K. Peptide antibiotics: an alternative and effective antimicrobial strategy to circumvent fungal infections. Peptides 2009; 30:999-1006. [PMID: 19428779 DOI: 10.1016/j.peptides.2009.01.026] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2008] [Revised: 01/26/2009] [Accepted: 01/26/2009] [Indexed: 10/21/2022]
Abstract
Mycosis, caused by both filamentous fungi and pathogenic yeasts is a major concern nowadays especially in the immunocompromised patient population. The emergence of pathogenic fungi resistant to current therapies in the last few decades has intensified the search for new antifungals like cationic peptides, which are the key components of innate defense mechanism. The review provides an inventory of different peptides from a diverse array of organisms from bacteria to mammals with proven antifungal activity, their therapeutic options and also about those which are in various stages of preclinical development. Literature, on the total and semi-synthetic variants of the parent peptides that exhibit an improved antifungal activity is also reviewed.
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Affiliation(s)
- K Ajesh
- Department of Biotechnology and Microbiology, Kannur University, Kerala, India
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Suk DH, Rejman D, Dykstra CC, Pohl R, Pankiewicz KW, Patterson SE. Phosphonoxins: rational design and discovery of a potent nucleotide anti-Giardia agent. Bioorg Med Chem Lett 2007; 17:2811-6. [PMID: 17360182 DOI: 10.1016/j.bmcl.2007.02.063] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2007] [Revised: 02/19/2007] [Accepted: 02/22/2007] [Indexed: 11/28/2022]
Abstract
Phosphonoxins, a new class of synthetic, rationally designed anti-microbial agents, are described. From this class a sub-micromolar inhibitor of Giardia trophozoite growth has been identified.
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Affiliation(s)
- Dae-Hwan Suk
- Center for Drug Design, Academic Health Center, University of Minnesota, Minneapolis, MN 55455, USA
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20
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Ganesan LT, Manavathu EK, Cutright JL, Alangaden GJ, Chandrasekar PH. In-vitro activity of nikkomycin Z alone and in combination with polyenes, triazoles or echinocandins against Aspergillus fumigatus. Clin Microbiol Infect 2005; 10:961-6. [PMID: 15521997 DOI: 10.1111/j.1469-0691.2004.00996.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The in-vitro activity of nikkomycin Z was investigated in combination with polyenes, triazoles or echinocandins against 20 clinical isolates of Aspergillus fumigatus with the fractional inhibitory concentration index (FICI) method. The drug interactions were classified as synergic (FICI < or = 0.5), no interaction (FICI > 0.5, but FICI < or = 4) or antagonistic (FICI > 4). The fungicidal activity of nikkomycin Z alone and in combination with a representative echinocandin (caspofungin) or triazole (voriconazole) was also examined with time-kill experiments and fungal cell viability assays. Two-drug combinations of nikkomycin Z with amphotericin B (FICI 3.59 +/- 0.57), amphotericin B lipid complex (FICI 3.95 +/- 0.74), liposomal amphotericin B (FICI 3.62 +/- 0.98), itraconazole (FICI 2.0 +/- 0.0), voriconazole (FICI 1.07 +/- 0.37), posaconazole (FICI 2.20 +/- 0.44) or ravuconazole (FICI 1.76 +/- 0.44) showed no interactions, but the pairwise combination of nikkomycin Z with caspofungin (FICI 0.22 +/- 0.19) or micafungin (FICI 0.35 +/- 0.27) showed synergic activity against A. fumigatus. Time-kill studies and fungal cell viability assays showed that neither nikkomycin Z nor caspofungin alone possessed fungicidal activity against A. fumigatus, whereas a combination of these two drugs at concentrations > or = 2 mg/L (> or = 0.031 x the concentration of drug that produced no visible growth) killed germinated conidia within 24 h in a concentration-dependent manner. These data suggest that two-drug combinations of nikkomycin Z with echinocandins, but not with polyenes and triazoles, have a synergic effect against A. fumigatus.
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Affiliation(s)
- L T Ganesan
- Division of Infectious Diseases, Department of Medicine, Wayne State University, Detroit, MI 48201, USA
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21
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Bhaket P, Stauffer CS, Datta A. Complex Peptidyl Nucleoside Antibiotics: Efficient Syntheses of the Glycosyl Nucleoside Amino Acid Cores. J Org Chem 2004; 69:8594-601. [PMID: 15575734 DOI: 10.1021/jo048586l] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Employing an amino acid chiral template strategy, the present research describes a general and highly efficient protocol for the rapid construction of enantiopure furanosyl and pyranosyl nucleoside amino acid cores as present in various complex peptidyl nucleoside antibiotics. Starting from easily available d-serine, the strategy and the approach involve rapid and efficient stereoselective synthesis of five- or six-membered lactone amino alcohols, followed by incorporation of the required functionalities of the target molecules on these strategically functionalized chiral templates.
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Affiliation(s)
- Pushpal Bhaket
- Department of Medicinal Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Lawrence, KS 66045, USA
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22
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Kelly MT, MacCallum DM, Clancy SD, Odds FC, Brown AJP, Butler G. The Candida albicans CaACE2 gene affects morphogenesis, adherence and virulence. Mol Microbiol 2004; 53:969-83. [PMID: 15255906 DOI: 10.1111/j.1365-2958.2004.04185.x] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Morphogenesis between yeast and hyphal growth is a characteristic associated with virulence in Candida albicans and involves changes in the cell wall. In Saccharomyces cerevisiae, the transcription factor pair Ace2p and Swi5p are key regulators of cell wall metabolism. Here, we have characterized the CaACE2 gene, which encodes the only C. albicans homologue of S. cerevisiae ACE2 and SWI5. Deleting CaACE2 results in a defect in cell separation, increased invasion of solid agar medium and inappropriate pseudohyphal growth, even in the absence of external inducers. The mutant cells have reduced adherence to plastic surfaces and generate biofilms with distinctly different morphology from wild-type cells. They are also avirulent in a mouse model. Deleting CaACE2 has no effect on expression of the chitinase gene CHT2, but expression of CHT3 and the putative cell wall genes CaDSE1 and CaSCW11 is reduced in both yeast and hyphal forms. The CaAce2 protein is localized to the daughter nucleus of large budded cells at the end of mitosis. C. albicans Ace2p therefore plays a major role in morphogenesis and adherence and resembles S. cerevisiae Ace2p in function.
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Affiliation(s)
- Mary T Kelly
- Department of Biochemistry, Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
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Affiliation(s)
- Luigi A Agrofoglio
- Institut de Chimie Organique et Analytique, UMR CNRS 6005, Université d'Orléans, BP 6759-Rue de Chartres, 45067 Orléans, France
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Lee DG, Park Y, Kim HN, Kim HK, Kim PI, Choi BH, Hahm KS. Antifungal mechanism of an antimicrobial peptide, HP (2--20), derived from N-terminus of Helicobacter pylori ribosomal protein L1 against Candida albicans. Biochem Biophys Res Commun 2002; 291:1006-13. [PMID: 11866466 DOI: 10.1006/bbrc.2002.6548] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The antifungal activity and mechanism of HP (2-20), a peptide derived from the N-terminus sequence of Helicobacter pylori Ribosomal Protein L1 were investigated. HP (2--20) displayed a strong antifungal activity against various fungi, and the antifungal activity was inhibited by Ca(2+) and Mg(2+) ions. In order to investigate the antifungal mechanism(s) of HP (2-20), fluorescence activated flow cytometry was performed. As determined by propidium iodide staining, Candida albicans treated with HP (2-20) showed a higher fluorescence intensity than untreated cells and was similar to melittin-treated cells. The effect on fungal cell membranes was examined by investigating the change in membrane dynamics of C. albicans using 1,6-diphenyl-1,3,5-hexatriene as a membrane probe and by testing the membrane disrupting activity using liposome (PC/PS; 3:1, w/w) and by treating protoplasts of C. albicans with the peptide. The action of peptide against fungal cell membrane was further examined by the potassium-release test, and HP (2-20) was able to increase the amount of K(+) released from the cells. The result suggests that HP (2-20) may exert its antifungal activity by disrupting the structure of cell membrane via pore formation or directly interacts with the lipid bilayers in a salt-dependent manner.
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Affiliation(s)
- Dong Gun Lee
- Research Center for Proteineous Materials, Chosun University, 375 Seosuk-Dong, Dong-Ku, Kwangju 501-759, Korea
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25
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Dash C, Ahmad A, Nath D, Rao M. Novel bifunctional inhibitor of xylanase and aspartic protease: implications for inhibition of fungal growth. Antimicrob Agents Chemother 2001; 45:2008-17. [PMID: 11408216 PMCID: PMC90593 DOI: 10.1128/aac.45.7.2008-2017.2001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A novel bifunctional inhibitor (ATBI) from an extremophilic Bacillus sp. exhibiting an activity against phytopathogenic fungi, including Alternaria, Aspergillus, Curvularia, Colletotricum, Fusarium, and Phomopsis species, and the saprophytic fungus Trichoderma sp. has been investigated. The 50% inhibitory concentrations of ATBI ranged from 0.30 to 5.9 microg/ml, whereas the MIC varied from 0.60 to 3.5 microg/ml for the fungal growth inhibition. The negative charge and the absence of periodic secondary structure in ATBI suggested an alternative mechanism for fungal growth inhibition. Rescue of fungal growth inhibition by the hydrolytic products of xylanase and aspartic protease indicated the involvement of these enzymes in cellular growth. The chemical modification of Asp or Glu or Lys residues of ATBI by 2,4,6-trinitrobenzenesulfonic acid and Woodward's reagent K, respectively, abolished its antifungal activity. In addition, ATBI also inhibited xylanase and aspartic protease competitively, with K(i) values 1.75 and 3.25 microM, respectively. Our discovery led us to envisage a paradigm shift in the concept of fungal growth inhibition for the role of antixylanolytic activity. Here we report for the first time a novel class of antifungal peptide, exhibiting bifunctional inhibitory activity.
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Affiliation(s)
- C Dash
- Division of Biochemical Sciences, National Chemical Laboratory, Pune-411 008, India
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26
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Bigliardi E, Bernuzzi AM, Corona S, Gatti S, Scaglia M, Sacchi L. In vitro efficacy of nikkomycin Z against the human isolate of the microsporidian species Encephalitozoon hellem. Antimicrob Agents Chemother 2000; 44:3012-6. [PMID: 11036015 PMCID: PMC101595 DOI: 10.1128/aac.44.11.3012-3016.2000] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Since 1985 microsporidia have been recognized as a cause of emerging infections in humans, mainly in immunocompromised human immunodeficiency virus-positive subjects. As chitin is a basic component of the microsporidian infective stage, the spore, we evaluated in vitro the susceptibility of a human-derived strain of Encephalitozoon hellem to nikkomycin Z, a peptide-nucleoside antibiotic known as a competitive inhibitor of chitin synthase enzymes. Transmission electron microscopy showed that this drug, at 25 microgram/ml, reduced the number of parasitic foci by about 35% +/- standard deviation after 7 days of culture (P < 0.0001) and induced cell damage of both mature and immature spores and also other sporogonic and merogonic stages. In particular, an irregular outline of the cell shape and an abnormally condensed cytoplasm in meronts and sporonts were documented. Also, the polar tubule and the polaroplast membranes appeared disarrayed in the sporoblast stage. The spore wall showed an enlarged endospore and delaminated exospore. Mature spores had a complete cytoplasmic disorganization and a swollen and delaminated cell wall. No ultrastructural cell damage was observed in uninfected control cultures treated with the drug.
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Affiliation(s)
- E Bigliardi
- Department of Evolutionary Biology, University of Siena, Pavia, Italy
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De Lucca AJ. Antifungal peptides: potential candidates for the treatment of fungal infections. Expert Opin Investig Drugs 2000; 9:273-99. [PMID: 11060677 DOI: 10.1517/13543784.9.2.273] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Many diversely produced natural peptides, as well as those produced semisynthetically and synthetically, have been found to inhibit the growth or even be lethal to a wide range of fungi. Some of these have the potential to aid mankind in combating mycoses caused by emerging pathogens or as a result of the increasing number of antibiotic-resistant fungi. Antifungal peptides may also assist in non-medical fields such as agriculture. For example, introduction by transgenic research of antifungal peptides could improve crop production yields by increasing host resistance to fungal invasion. The aim of this review is to provide information on research on these important peptides.
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Affiliation(s)
- A J De Lucca
- Southern Regional Research Center, USDA, ARS 1100 Robert E. Lee Blvd. New Orleans, LA 70124, USA.
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Li RK, Rinaldi MG. In vitro antifungal activity of nikkomycin Z in combination with fluconazole or itraconazole. Antimicrob Agents Chemother 1999; 43:1401-5. [PMID: 10348760 PMCID: PMC89286 DOI: 10.1128/aac.43.6.1401] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nikkomycins are nucleoside-peptide antibiotics produced by Streptomyces species with antifungal activities through the inhibition of chitin synthesis. We investigated the antifungal activities of nikkomycin Z alone and in combination with fluconazole and itraconazole. Checkerboard synergy studies were carried out by a macrobroth dilution procedure with RPMI 1640 medium at pH 6.0. At least 10 strains of the following fungi were tested: Candida albicans, other Candida spp., Cryptococcus neoformans, Coccidioides immitis, Aspergillus spp., and dematiacious fungi (including Exophiala jeanselmei, Exophiala spinifera, Bipolaris spicifera, Wangiella dermatitidis, Ochroconis humicola, Phaeoannellomyces werneckii, and Cladophialophora bantiana), and 2 strains each of Fusarium, Scedosporium, Paecilomyces, Penicillium, and Trichoderma spp. A total of 110 isolates were examined. Inocula of fungal elements were standardized by hemacytometer counting or spectrophotometrically. MICs and minimum lethal concentrations (MLCs) were determined visually by comparison of growth in drug-treated tubes with growth in drug-free control tubes. Additive and synergistic interactions between nikkomycin and either fluconazole or itraconazole were observed against C. albicans, Candida parapsilosis, Cryptococcus neoformans, and Coccidioides immitis. Marked synergism was also observed between nikkomycin and itraconazole against Aspergillus fumigatus and Aspergillus flavus. No antagonistic interaction between the drugs was observed with any of the strains tested.
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Affiliation(s)
- R K Li
- Department of Pathology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas 28284, USA.
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29
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De Lucca AJ, Walsh TJ. Antifungal peptides: novel therapeutic compounds against emerging pathogens. Antimicrob Agents Chemother 1999; 43:1-11. [PMID: 9869556 PMCID: PMC89011 DOI: 10.1128/aac.43.1.1] [Citation(s) in RCA: 212] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- A J De Lucca
- Southern Regional Research Center, Agricultural Research Service, U. S. Department of Agriculture, New Orleans, Louisiana 70124, USA.
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30
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Wang JQ, Archer C, Li J, Bott SG, Wang PG. Thermophilic Esterases/Lipases as an Effective Tool for the Resolution of Nucleoside Diastereoisomers: Convenient One-Pot Synthesis of α-l-Taluronamide and β-d-Alluronamide Nucleosides. J Org Chem 1998. [DOI: 10.1021/jo972086t] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jian-qiang Wang
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, and Department of Chemistry, University of North Texas, P.O. Box 5068, Denton, Texas 76203
| | - Christopher Archer
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, and Department of Chemistry, University of North Texas, P.O. Box 5068, Denton, Texas 76203
| | - Jun Li
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, and Department of Chemistry, University of North Texas, P.O. Box 5068, Denton, Texas 76203
| | - Simon G. Bott
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, and Department of Chemistry, University of North Texas, P.O. Box 5068, Denton, Texas 76203
| | - Peng George Wang
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202, and Department of Chemistry, University of North Texas, P.O. Box 5068, Denton, Texas 76203
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Groll AH, Piscitelli SC, Walsh TJ. Clinical pharmacology of systemic antifungal agents: a comprehensive review of agents in clinical use, current investigational compounds, and putative targets for antifungal drug development. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 1998; 44:343-500. [PMID: 9547888 DOI: 10.1016/s1054-3589(08)60129-5] [Citation(s) in RCA: 288] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- A H Groll
- Immunocompromised Host Section, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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Rule of Intersection Point of Retention for Quinolone Medicines in Bonded-Phase Chromatography with Ion Suppression. Microchem J 1998. [DOI: 10.1006/mchj.1997.1528] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Polak A. Antifungal therapy, an everlasting battle. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 1997; 49:219-318. [PMID: 9388389 DOI: 10.1007/978-3-0348-8863-9_7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Del Mar González M, Díez-Orejas R, Molero G, Álvarez AM, Pla J, Pla J, Nombela C, Sánchez-PéArez M. Phenotypic characterization of a Candida albicans strain deficient in its major exoglucanase. MICROBIOLOGY (READING, ENGLAND) 1997; 143 ( Pt 9):3023-3032. [PMID: 9308184 DOI: 10.1099/00221287-143-9-3023] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Both alleles of the XOG1 gene of Candida albicans, which encodes a protein with exoglucanase activity, were sequentially disrupted. Enzymic analysis of either cell extracts or culture supernatants of disrupted strains revealed that this gene is responsible for the major exoglucanase activity in C. albicans, although residual exoglucanase activity could still be detected. xog1 null mutants showed similar growth rates in both rich and minimal liquid medium as compared to the wild-type strain, indicating that the enzyme is not essential for C. albicans growth. In addition, no differences were observed between wild-type and xog1 null mutants with respect to their ability to undergo dimorphic transition. However, small but repeatable differences were found between the wild-type and the null mutant with respect to susceptibility to chitin and glucan synthesis inhibitors. Using a murine model of experimental infection, no significant differences in virulence were observed. The xog1 null strain is thus a suitable recipient for studying Candida gene expression using the exoglucanase as a reporter gene.
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Affiliation(s)
- María Del Mar González
- Department of Microbiology II, Faculty of Pharmacy, University Complutense of Madrid, 28040 Madrid, Spain
| | - Rosalía Díez-Orejas
- Department of Microbiology II, Faculty of Pharmacy, University Complutense of Madrid, 28040 Madrid, Spain
| | - Gloria Molero
- Department of Microbiology II, Faculty of Pharmacy, University Complutense of Madrid, 28040 Madrid, Spain
| | - Alberto M Álvarez
- Flow and Confocal Cytometry Unit (CCF), Faculty of Pharmacy, University Complutense of Madrid, 28040 Madrid, Spain
| | - Jesús Pla
- Flow and Confocal Cytometry Unit (CCF), Faculty of Pharmacy, University Complutense of Madrid, 28040 Madrid, Spain
| | - Jesús Pla
- Department of Microbiology II, Faculty of Pharmacy, University Complutense of Madrid, 28040 Madrid, Spain
| | - CéAsar Nombela
- Department of Microbiology II, Faculty of Pharmacy, University Complutense of Madrid, 28040 Madrid, Spain
| | - Miguel Sánchez-PéArez
- Flow and Confocal Cytometry Unit (CCF), Faculty of Pharmacy, University Complutense of Madrid, 28040 Madrid, Spain
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Bulawa CE, Miller DW, Henry LK, Becker JM. Attenuated virulence of chitin-deficient mutants of Candida albicans. Proc Natl Acad Sci U S A 1995; 92:10570-4. [PMID: 7479842 PMCID: PMC40653 DOI: 10.1073/pnas.92.23.10570] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We have analyzed the role of chitin, a cell-wall polysaccharide, in the virulence of Candida albicans. Mutants with a 5-fold reduction in chitin were obtained in two ways: (i) by selecting mutants resistant to Calcofluor, a fluorescent dye that binds to chitin and inhibits growth, and (ii) by disrupting CHS3, the C. albicans homolog of CSD2/CAL1/DIT101/KT12, a Saccharomyces cerevisiae gene required for synthesis of approximately 90% of the cell-wall chitin. Chitin-deficient mutants have no obvious alterations in growth rate, sugar assimilation, chlamydospore formation, or germ-tube formation in various media. When growing vegetatively in liquid media, the mutants tend to clump and display minor changes in morphology. Staining of cells with the fluorescent dye Calcofluor indicates that CHS3 is required for synthesis of the chitin rings found on the surface of yeast cells but not formation of septa in either yeast cells or germ tubes. Despite their relatively normal growth, the mutants are significantly less virulent than the parental strain in both immunocompetent and immunosuppressed mice; at 13 days after infection, survival was 95% in immunocompetent mice that received chs3/chs3 cells and 10% in immunocompetent mice that received an equal dose of chs3/CHS3 cells. Chitin-deficient strains can colonize the organs of infected mice, suggesting that the reduced virulence of the mutants is not due to accelerated clearing.
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Affiliation(s)
- C E Bulawa
- Department of Molecular Biology, Myco Pharmaceuticals Inc., Cambridge, MA 02139, USA
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Graybill JR. Antifungal drugs and resistance. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1995; 390:217-34. [PMID: 8718616 DOI: 10.1007/978-1-4757-9203-4_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- J R Graybill
- Department of Medicine, Audie Murphy V.A. Hospital, San Antonio, TX, USA
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