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Valdez AF, de Souza TN, Bonilla JJA, Zamith-Miranda D, Piffer AC, Araujo GRS, Guimarães AJ, Frases S, Pereira AK, Fill TP, Estevao IL, Torres A, Almeida IC, Nosanchuk JD, Nimrichter L. Traversing the Cell Wall: The Chitinolytic Activity of Histoplasma capsulatum Extracellular Vesicles Facilitates Their Release. J Fungi (Basel) 2023; 9:1052. [PMID: 37998859 PMCID: PMC10672645 DOI: 10.3390/jof9111052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/15/2023] [Accepted: 10/26/2023] [Indexed: 11/25/2023] Open
Abstract
Histoplasma capsulatum is the causative agent of histoplasmosis. Treating this fungal infection conventionally has significant limitations, prompting the search for alternative therapies. In this context, fungal extracellular vesicles (EVs) hold relevant potential as both therapeutic agents and targets for the treatment of fungal infections. To explore this further, we conducted a study using pharmacological inhibitors of chitinase (methylxanthines) to investigate their potential to reduce EV release and its subsequent impact on fungal virulence in an in vivo invertebrate model. Our findings revealed that a subinhibitory concentration of the methylxanthine, caffeine, effectively reduces EV release, leading to a modulation of H. capsulatum virulence. To the best of our knowledge, this is the first reported instance of a pharmacological inhibitor that reduces fungal EV release without any observed fungicidal effects.
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Affiliation(s)
- Alessandro F. Valdez
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (A.F.V.); (T.N.d.S.); (J.J.A.B.); (A.C.P.)
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Taiane Nascimento de Souza
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (A.F.V.); (T.N.d.S.); (J.J.A.B.); (A.C.P.)
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Jhon Jhamilton Artunduaga Bonilla
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (A.F.V.); (T.N.d.S.); (J.J.A.B.); (A.C.P.)
| | - Daniel Zamith-Miranda
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Alicia Corbellini Piffer
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (A.F.V.); (T.N.d.S.); (J.J.A.B.); (A.C.P.)
- Unité Biologie des ARN des Pathogènes Fongiques, Départament de Mycologie, Institut Pasteur, Université Paris Cité, F-75015 Paris, France
| | - Glauber R. S. Araujo
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (G.R.S.A.); (S.F.)
| | - Allan J. Guimarães
- Instituto Biomédico, Departamento de Microbiologia e Parasitologia—MIP, Universidade Federal Fluminense, Niterói 24210-130, RJ, Brazil;
- Rede Micologia, RJ, FAPERJ, Rio de Janeiro 21941-902, RJ, Brazil
| | - Susana Frases
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (G.R.S.A.); (S.F.)
- Rede Micologia, RJ, FAPERJ, Rio de Janeiro 21941-902, RJ, Brazil
| | - Alana Kelyene Pereira
- Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo 13083-970, SP, Brazil; (A.K.P.); (T.P.F.)
| | - Taicia Pacheco Fill
- Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo 13083-970, SP, Brazil; (A.K.P.); (T.P.F.)
| | - Igor L. Estevao
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas El Paso, El Paso, TX 79902, USA; (I.L.E.); (A.T.); (I.C.A.)
| | - Angel Torres
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas El Paso, El Paso, TX 79902, USA; (I.L.E.); (A.T.); (I.C.A.)
| | - Igor C. Almeida
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas El Paso, El Paso, TX 79902, USA; (I.L.E.); (A.T.); (I.C.A.)
| | - Joshua D. Nosanchuk
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Leonardo Nimrichter
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil; (A.F.V.); (T.N.d.S.); (J.J.A.B.); (A.C.P.)
- Rede Micologia, RJ, FAPERJ, Rio de Janeiro 21941-902, RJ, Brazil
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de Oliveira Viana J, Silva E Souza E, Sbaraini N, Vainstein MH, Gomes JNS, de Moura RO, Barbosa EG. Scaffold repositioning of spiro-acridine derivatives as fungi chitinase inhibitor by target fishing and in vitro studies. Sci Rep 2023; 13:7320. [PMID: 37147323 PMCID: PMC10163251 DOI: 10.1038/s41598-023-33279-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 04/11/2023] [Indexed: 05/07/2023] Open
Abstract
The concept of "one target, one drug, one disease" is not always true, as compounds with previously described therapeutic applications can be useful to treat other maladies. For example, acridine derivatives have several potential therapeutic applications. In this way, identifying new potential targets for available drugs is crucial for the rational management of diseases. Computational methodologies are interesting tools in this field, as they use rational and direct methods. Thus, this study focused on identifying other rational targets for acridine derivatives by employing inverse virtual screening (IVS). This analysis revealed that chitinase enzymes can be potential targets for these compounds. Subsequently, we coupled molecular docking consensus analysis to screen the best chitinase inhibitor among acridine derivatives. We observed that 3 compounds displayed potential enhanced activity as fungal chitinase inhibitors, showing that compound 5 is the most active molecule, with an IC50 of 0.6 ng/µL. In addition, this compound demonstrated a good interaction with the active site of chitinases from Aspergillus fumigatus and Trichoderma harzianum. Additionally, molecular dynamics and free energy demonstrated complex stability for compound 5. Therefore, this study recommends IVS as a powerful tool for drug development. The potential applications are highlighted as this is the first report of spiro-acridine derivatives acting as chitinase inhibitors that can be potentially used as antifungal and antibacterial candidates.
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Affiliation(s)
- Jéssika de Oliveira Viana
- Post-Graduate Program in Bioinformatics, Bioinformatics Multidisciplinary Environment, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Eden Silva E Souza
- School of Biomolecular and Biomedical Science & BiOrbic-Bioeconomy Research Center, University College Dublin, Dublin, Ireland
| | - Nicolau Sbaraini
- Biotechnology Center, Postgraduate Program in Cellular and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Marilene Henning Vainstein
- Biotechnology Center, Postgraduate Program in Cellular and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | | | | | - Euzébio Guimarães Barbosa
- Post-Graduate Program in Bioinformatics, Bioinformatics Multidisciplinary Environment, Federal University of Rio Grande do Norte, Natal, Brazil.
- Post-Graduate Program in Pharmaceutical Sciences, Faculty of Pharmacy, Federal University of Rio Grande do Norte, Natal, Brazil.
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Chi M, Gu L, Zhang L, Lin J, Xu Q, Jiang N, Wang Y, Qi Y, Diao W, Yi W, Zhao G, Li C. Pentoxifylline treats Aspergillus fumigatus keratitis by reducing fungal burden and suppressing corneal inflammation. Eur J Pharmacol 2023; 945:175607. [PMID: 36822458 DOI: 10.1016/j.ejphar.2023.175607] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 02/15/2023] [Accepted: 02/16/2023] [Indexed: 02/23/2023]
Abstract
Fungal keratitis (FK) is a blinding ocular disease, which mainly results from fungal damage and excessive inflammation. Pentoxifylline, a kind of methylxanthine, has been discovered to have anti-inflammatory properties in various infectious diseases, hinting a potential therapeutic effect on treating corneal fungal infection. Whereas, the therapeutic impact of pentoxifylline on fungal keratitis is still uncertain. This study investigated the antifungal capability against Aspergillus fumigatus and the anti-inflammatory role of pentoxifylline by activating nuclear factor, erythroid 2 like 2 (Nrf2)/heme oxygenase1 (HO1) pathway in the process of FK. In our research, we demonstrated that pentoxifylline could effectively inhibit fungal growth and inflammatory reaction. Pentoxifylline reduced the production of pro-inflammatory factors by stimulating the Nrf2/HO1 pathway. Although there was no statistical difference between the curative efficacy of pentoxifylline and natamycin application to FK, pentoxifylline could promote corneal epithelial repair and was less toxicity to the ocular surface than natamycin. In conclusion, pentoxifylline performs antifungal and anti-inflammatory effects by lessening the fungus burden and activating the Nrf2/HO1 pathway, hinting that it has the potential to be a new therapeutic medication for Aspergillus fumigatus keratitis.
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Affiliation(s)
- Menghui Chi
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China
| | - Lingwen Gu
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China
| | - Lina Zhang
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China
| | - Jing Lin
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China
| | - Qiang Xu
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China
| | - Nan Jiang
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China
| | - Yuwei Wang
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China
| | - Yinghe Qi
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China
| | - Weilin Diao
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China
| | - Wendan Yi
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China
| | - Guiqiu Zhao
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China.
| | - Cui Li
- Department of Ophthalmology, The Affiliated Hospital of Qingdao University, No. 16 Jiangsu Road, Qingdao, Shandong Province, 266003, China.
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Aranda C, Méndez I, Barra PJ, Hernández-Montiel L, Fallard A, Tortella G, Briones E, Durán P. Melanin Induction Restores the Pathogenicity of Gaeumannomyces graminis var. tritici in Wheat Plants. J Fungi (Basel) 2023; 9:jof9030350. [PMID: 36983518 PMCID: PMC10058861 DOI: 10.3390/jof9030350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/18/2023] Open
Abstract
One of the most challenging aspects of long-term research based on microorganisms is the maintenance of isolates under ex situ conditions, particularly the conservation of phytopathological characteristics. Our research group has worked for more than 10 years with Gaumannomyces graminis var. tritici (Ggt), the main biotic factor affecting wheat. In this sense we preserved the microorganisms in oil overlaid. However, several strains preserved for a long time lost their pathogenicity. These strains show white and non-infective mycelia. In this sense, we hypothesized that this is attributable to low melanin content. Melanin is a natural pigment mainly involved in UV protection, desiccation, salinity, oxidation, and fungal pathogenicity. Therefore, understanding the melanin role on Ggt pathogenicity is fundamental to developing melanin activation strategies under laboratory studies. In this study, we induce melanin activation by UV-A light chamber, 320 to 400 nm (T1) and temperature changes of 30 °C, 15 °C, and 20 °C (T2). Fungal pathogenicity was evaluated by determination of blackening roots and Ggt was quantified by real-time PCR in inoculated wheat plants. Results revealed that Ggt grown under UV-A (T1) conditions showed around 40% higher melanin level with a concomitant effect on root infection (98% of blackened roots) and 4-fold more Ggt genome copy number compared with the control (non-infective mycelia) being T1, a more inductor factor compared with T2. These findings would support the role of melanin in pathogenicity in darkly pigmented fungi such as Ggt and could serve as a basis for activating pathogenicity under laboratory conditions.
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Affiliation(s)
- Camila Aranda
- Programa de Doctorado en Ciencias de Recursos Naturales, Universidad de La Frontera, Temuco 4811230, Chile
- Biocontrol Research Laboratory, Universidad de La Frontera, Temuco 4811230, Chile
| | - Isabel Méndez
- Programa de Doctorado en Ciencias de Recursos Naturales, Universidad de La Frontera, Temuco 4811230, Chile
- Biocontrol Research Laboratory, Universidad de La Frontera, Temuco 4811230, Chile
| | - Patricio Javier Barra
- Biocontrol Research Laboratory, Universidad de La Frontera, Temuco 4811230, Chile
- Scientific and Technological Bioresource Nucleus, Universidad de La Frontera, Temuco 4811230, Chile
| | - Luis Hernández-Montiel
- Nanotechnology and Microbial Biocontrol Group, Centro de Investigaciones Biológicas del Noroeste, Av. Politécnico Nacional 195, Col. Playa Palo de Santa Rita Sur, La Paz 23090, Mexico
| | - Ana Fallard
- Biocontrol Research Laboratory, Universidad de La Frontera, Temuco 4811230, Chile
| | - Gonzalo Tortella
- Scientific and Technological Bioresource Nucleus, Universidad de La Frontera, Temuco 4811230, Chile
| | - Evelyn Briones
- Biocontrol Research Laboratory, Universidad de La Frontera, Temuco 4811230, Chile
| | - Paola Durán
- Biocontrol Research Laboratory, Universidad de La Frontera, Temuco 4811230, Chile
- Scientific and Technological Bioresource Nucleus, Universidad de La Frontera, Temuco 4811230, Chile
- Facultad de Ciencias Agropecuarias y Medioambiente, Departamento de Producción Agropecuaria, Universidad de La Frontera, Temuco 4811230, Chile
- Correspondence:
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Discovery of Octahydroisoindolone as a Scaffold for the Selective Inhibition of Chitinase B1 from Aspergillus fumigatus: In Silico Drug Design Studies. Molecules 2021; 26:molecules26247606. [PMID: 34946697 PMCID: PMC8705689 DOI: 10.3390/molecules26247606] [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: 11/22/2021] [Revised: 12/08/2021] [Accepted: 12/13/2021] [Indexed: 11/21/2022] Open
Abstract
Chitinases represent an alternative therapeutic target for opportunistic invasive mycosis since they are necessary for fungal cell wall remodeling. This study presents the design of new chitinase inhibitors from a known hydrolysis intermediate. Firstly, a bioinformatic analysis of Aspergillus fumigatus chitinase B1 (AfChiB1) and chitotriosidase (CHIT1) by length and conservation was done to obtain consensus sequences, and molecular homology models of fungi and human chitinases were built to determine their structural differences. We explored the octahydroisoindolone scaffold as a potential new antifungal series by means of its structural and electronic features. Therefore, we evaluated several synthesis-safe octahydroisoindolone derivatives by molecular docking and evaluated their AfChiB1 interaction profile. Additionally, compounds with the best interaction profile (1–5) were docked within the CHIT1 catalytic site to evaluate their selectivity over AfChiB1. Furthermore, we considered the interaction energy (MolDock score) and a lipophilic parameter (aLogP) for the selection of the best candidates. Based on these descriptors, we constructed a mathematical model for the IC50 prediction of our candidates (60–200 μM), using experimental known inhibitors of AfChiB1. As a final step, ADME characteristics were obtained for all the candidates, showing that 5 is our best designed hit, which possesses the best pharmacodynamic and pharmacokinetic character.
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Feng C, Zhang M, Zhang S, Zhang J, Li C, Zhou J. Therapeutic effects of pentoxifylline on invasive pulmonary aspergillosis in immunosuppressed mice. BMC Pulm Med 2021; 21:31. [PMID: 33468116 PMCID: PMC7814429 DOI: 10.1186/s12890-021-01396-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 01/01/2021] [Indexed: 12/22/2022] Open
Abstract
Background The most common and severe infection of Aspergillus fumigatus is invasive pulmonary aspergillosis (IPA), which is usually seen in immunocompromised patients. Neutropenia is the primary risk factor implicated in IPA; however, IPA also occurs in patients without neutropenia, namely, those who are immunosuppressed owing to long-term corticosteroid use. With IPA-associated mortality as high as 51–79%, novel and effective treatment strategies are urgently needed. Pentoxifylline (PTX) has been shown to competitively inhibit the family 18 chitinases in fungi, which may be an new antifungal therapy. Hence, the aim of our study was to compare neutropenic and non-neutropenic IPA mouse models, and to evaluate the effect of PTX on IPA in immunosuppressed mice. Methods C57BL/6J mice were pre-treated with cyclophosphamide and hydrocortisone. Neutropenic model IPA mice (CTX-IPA) and non-neutropenic IPA mice (HC-IPA) were established by intranasal administration of Aspergillus fumigatus spore suspension. A subset of each group was injected with PTX post-infection. Among these groups, we compared overall survival, pulmonary fungal burden, lung hispathology, and myeloperoxidase (MPO), interleukin 8 (IL-8), and mammalian chitinase concentration in the bronchoalveolar lavage fluid (BALF). Results The survival rate of the HC-IPA group was higher than that of the CTX-IPA group, and pulmonary fungal burden was also lower (p < 0.05). The CTX-IPA group showed infiltration of alveolae and blood vessels by numerous hyphae of A. fumigatus. The HC-IPA group exhibited destruction of bronchi, expansion of alveolar septa, increased macrophages aggregation, significant neutrophil infiltration and a few hyphae in peribronchial areas. After PTX treatment, improvement was observed in survival duration and pulmonary fungal burden in HC-IPA mice. MPO and IL-8 levels were lower in the HC-IPA + PTX group compared to the corresponding levels in the HC-IP group. Chitotriosidase (CHIT1) and Chitinase 3-like 1 (CHI3L1) expression in the HC-IPA group was decreased after PTX treatment (p < 0.05). Conclusion PTX was found to exert a therapeutic effect in a non-neutropenic mouse model of IPA, which may lead to the development of novel strategies for IPA treatment.
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Affiliation(s)
- Chunlai Feng
- Department of Respiratory Medicine, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, 213003, China.
| | - Ming Zhang
- Department of Respiratory Medicine, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, 213003, China
| | - Sujuan Zhang
- Department of Respiratory Medicine, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, 213003, China
| | - Jun Zhang
- Comprehensive Laboratory, The Third Affiliated Hospital of Soochow University, Changzhou, China
| | - Chong Li
- Department of Respiratory Medicine, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, 213003, China
| | - Jun Zhou
- Department of Respiratory Medicine, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, 213003, China
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Wang F, Gao W, Sun J, Mao X, Liu K, Xu J, Fu D, Yuan M, Wang H, Chen N, Xiao S, Xue C. NADPH Oxidase ClNOX2 Regulates Melanin-Mediated Development and Virulence in Curvularia lunata. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2020; 33:1315-1329. [PMID: 32815478 DOI: 10.1094/mpmi-06-20-0138-r] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The role of NADPH oxidases (NOXs) in pathogenesis and development in the Curvularia leaf spot agent Curvularia lunata remains poorly understood. In this study, we identified C. lunata ClNOX2, which localized to the plasma membrane and was responsible for reactive oxygen species (ROS) generation. Scavenging the ROS production inhibited the conidial germination and appressorial formation. The ClNOX2 and ClBRN1 deletion mutants were defective in 1,8-dihydroxynaphthalene (DHN) melanin accumulation, appressorial formation, and cellulase synthesis and exhibited lower virulence. However, disruption of the ClNOX2 and ClBRN1 genes facilitated hyphal growth, enhanced stress adaptation to cell-wall-disrupting agents, and promoted developmental processes such as conidiation, conidial germination, and pseudothecium and ascus formation. Interestingly, loss of ClM1, the cell wall integrity (CWI) mitogen-activated protein kinase gene in C. lunata, led to morphology and pathogenicity phenotypes similar to ClNOX2 and ClBRN1 deletion mutants such as abnormal conidia, fewer appressoria, less melanin, increased hyphal growth, and enhanced tolerance to Congo red (CR). These results indicated that the ClNOX2 gene plays an important role in C. lunata development and virulence via regulating intracellular DHN melanin biosynthesis. Quantitative reverse-transcription PCR revealed that the ClNOX2-related ROS signaling pathway and ClM1-mediated CWI signaling pathway are cross-linked in regulating DHN melanin biosynthesis. Our findings provide new insights into how ClNOX2 participates in pathogenesis and development in hemibiotrophic plant fungal pathogens.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Fen Wang
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Weida Gao
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Jiaying Sun
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Xiuwen Mao
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Kexin Liu
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Jingru Xu
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Dandan Fu
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Mingyue Yuan
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Hongchuan Wang
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Nan Chen
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Shuqin Xiao
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
| | - Chunsheng Xue
- College of Plant Protection, Shenyang Agricultural University, Shenyang, 110161, China
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Glycoside hydrolase family 18 chitinases: The known and the unknown. Biotechnol Adv 2020; 43:107553. [DOI: 10.1016/j.biotechadv.2020.107553] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 03/09/2020] [Accepted: 04/20/2020] [Indexed: 12/13/2022]
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9
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Silva E Souza E, Barcellos VDA, Sbaraini N, Reuwsaat JCV, Schneider RDO, da Silva AC, Garcia AWA, von Poser GL, Barbosa EG, Lima JPMS, Vainstein MH. A Plumieridine-Rich Fraction From Allamanda polyantha Inhibits Chitinolytic Activity and Exhibits Antifungal Properties Against Cryptococcus neoformans. Front Microbiol 2020; 11:2058. [PMID: 32983042 PMCID: PMC7483551 DOI: 10.3389/fmicb.2020.02058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 08/05/2020] [Indexed: 12/28/2022] Open
Abstract
Cryptococcosis is a fungal infection caused mainly by the pathogenic yeasts Cryptococcus neoformans and Cryptococcus gattii. The infection initiates with the inhalation of propagules that are then deposited in the lungs. If not properly treated, cryptococci cells can disseminate and reach the central nervous system. The current recommended treatment for cryptococcosis employs a three-stage regimen, with the administration of amphotericin B, flucytosine and fluconazole. Although effective, these drugs are often unavailable worldwide, can lead to resistance development, and may display toxic effects on the patients. Thus, new drugs for cryptococcosis treatment are needed. Recently, an iridoid named plumieridine was found in Allamanda polyantha seed extract; it exhibited antifungal activity against C. neoformans with a MIC of 250 μg/mL. To address the mode of action of plumieridine, several in silico and in vitro experiments were performed. Through a ligand-based a virtual screening approach, chitinases were identified as potential targets. Confirmatory in vitro assays showed that C. neoformans cell-free supernatant incubated with plumieridine displayed reduced chitinase activity, while chitinolytic activity was not inhibited in the insoluble cell fraction. Additionally, confocal microscopy revealed changes in the distribution of chitooligomers in the cryptococcal cell wall, from a polarized to a diffuse cell pattern state. Remarkably, further assays have shown that plumieridine can also inhibit the chitinolytic activity from the supernatant and cell-free extracts of bacteria, insect and mouse-derived macrophage cells (J774.A1). Together, our results suggest that plumieridine can be a broad-spectrum chitinase inhibitor.
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Affiliation(s)
- Eden Silva E Souza
- Bioinformatics Multidisciplinary Environment, Universidade Federal do Rio Grande do Norte, Natal, Brazil
| | | | - Nicolau Sbaraini
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | | | | | - Adriana Corrêa da Silva
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil
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10
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An Antivirulence Approach for Preventing Cryptococcus neoformans from Crossing the Blood-Brain Barrier via Novel Natural Product Inhibitors of a Fungal Metalloprotease. mBio 2020; 11:mBio.01249-20. [PMID: 32694141 PMCID: PMC7374060 DOI: 10.1128/mbio.01249-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Fungal infections like cryptococcal meningitis are difficult to resolve because of the limited therapies available. The small arsenal of antifungal drugs reflect the difficulty in finding available targets in fungi because like mammalian cells, fungi are eukaryotes. The limited efficacy, toxicity, and rising resistance of antifungals contribute to the high morbidity and mortality of fungal infections and further underscore the dire but unmet need for new antifungal drugs. The traditional approach in antifungal drug development has been to target fungal growth, but an attractive alternative is to target mechanisms of pathogenesis. An important attribute of Cryptococcus neoformans (Cn) pathogenesis is its ability to enter the central nervous system. Here, we describe a large-scale screen that identified three natural products that prevented Cn from crossing the blood-brain barrier by inhibiting the virulence factor Mpr1 without affecting the growth of Cn. We propose that compounds identified here could be further developed as antivirulence therapy that would be administered preemptively or serve as a prophylactic in patients at high risk for developing cryptococcal meningitis. Cryptococcus neoformans (Cn) is the leading cause of fungal meningitis, a deadly disease with limited therapeutic options. Dissemination to the central nervous system hinges on the ability of Cn to breach the blood-brain barrier (BBB) and is considered an attribute of Cn virulence. Targeting virulence instead of growth for antifungal drug development has not been fully exploited despite the benefits of this approach. Mpr1 is a secreted fungal metalloprotease not required for fungal growth, but rather, it functions as a virulence factor by facilitating Cn migration across the BBB. This central role for Mpr1, its extracellular location, and lack of expression in mammalian cells make Mpr1 a high-value target for an antivirulence approach aimed at developing therapeutics for cryptococcal meningitis. To test this notion, we devised a large-scale screen to identify compounds that prohibited Cn from crossing the BBB by selectively blocking Mpr1 proteolytic activity, without inhibiting the growth of Cn. A phytochemical natural product-derived library was screened to identify new molecular scaffolds of prototypes unique to a Cn microecosystem. Of the 240 pure natural products examined, 3 lead compounds, abietic acid, diosgenin, and lupinine inhibited Mpr1 proteolytic activity with 50% inhibitory concentration (IC50) values of <10 μM, displayed little to no mammalian cell toxicity, and did not affect Cn growth. Notably, the lead compounds blocked Cn from crossing the BBB, without damaging the barrier integrity, suggesting the bioactive molecules had no off-target effects. We propose that these new drug scaffolds are promising candidates for the development of antivirulence therapy against cryptococcal meningitis.
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11
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Galvez-Llompart M, Zanni R, Galvez J, Garcia-Domenech R. Molecular Topology QSAR Strategy for Crop Protection: New Natural Fungicides with Chitin Inhibitory Activity. ACS OMEGA 2020; 5:16358-16365. [PMID: 32685798 PMCID: PMC7364431 DOI: 10.1021/acsomega.0c00177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 03/23/2020] [Indexed: 05/11/2023]
Abstract
Nowadays, crop protection is a major concern and how to proceed is a delicate point of contention. New products must be safe and ecofriendly in accordance with the actual legislation. In this context, we present a quantitative structure-activity relationship strategy based on molecular topology as a tool for generating natural products as potential fungicides following a mechanism of action based on the synthesis of chitin inhibition (chitinase inhibition). Two discriminant equations using statistical linear discriminant analysis were used to identify three potential candidates (1-methylxanthine, hematommic acid, and antheraxanthin). The equations showed accuracy and specificity levels above 80%, minimizing the risk of selecting false active compounds.
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Affiliation(s)
- Maria Galvez-Llompart
- Instituto
de Tecnologia Quimica, UPV-CSIC, Universidad
Politecnica de Valencia, Avenida de los Naranjos s/n, Valencia E-46022, Spain
- Molecular
Topology and Drug Design Unit, Department of Physical Chemistry, University of Valencia, Valencia 46010, Spain
| | - Riccardo Zanni
- Departamento
de Microbiologia, Facultad de Ciencias, Universidad de Malaga, Bulevar Louis Pasteur 31, Malaga 29071, Spain
- Molecular
Topology and Drug Design Unit, Department of Physical Chemistry, University of Valencia, Valencia 46010, Spain
| | - Jorge Galvez
- Molecular
Topology and Drug Design Unit, Department of Physical Chemistry, University of Valencia, Valencia 46010, Spain
| | - Ramon Garcia-Domenech
- Molecular
Topology and Drug Design Unit, Department of Physical Chemistry, University of Valencia, Valencia 46010, Spain
- . Phone: +34-963544291
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12
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Bresciani FR, Santi L, Beys-da-Silva WO, Berger M, Barcellos VDA, Schripsema J, von Poser GL, Guimarães JA, Vainstein MH. Antifungal activity of Allamanda polyantha seed extract and its iridoids promote morphological alterations in Cryptococcus spp. Arch Pharm (Weinheim) 2020; 353:e2000133. [PMID: 32638423 DOI: 10.1002/ardp.202000133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/15/2020] [Accepted: 06/18/2020] [Indexed: 12/20/2022]
Abstract
Cryptococcosis, caused by Cryptococcus spp., is an invasive fungal infection of the central nervous system, associated with high mortality, affecting mainly immunocompromised patients. Due to the development of resistance to the current therapy, there is an urgent need for less toxic and more effective antifungal agents. In this study, we describe the antifungal activity against Cryptococcus spp. of an aqueous seed extract from Allamanda polyantha (ASEAP) and two iridoids, plumieride and plumieridine, isolated from this extract with an antifungal activity. The capsule formation and the morphological alterations were evaluated using fluorescent microscopy. The cytotoxic activity was also investigated. The minimal inhibitory concentration (MIC) values of ASEAP for Cryptococcus gattii were 70 and 36 µg/ml (for the R265 and R272 strains, respectively) and 563 µg/ml for Cryptococcus neoformans H99. ASEAP inhibited C. neoformans H99 capsule formation, an important virulence factor, and decreased the cell body size for both the C. gattii strains. H99 cells also presented morphological alterations, with defects in bud detachment and nuclear fragmentation. Plumieride and plumieridine presented higher MIC values than ASEAP, indicating that other compounds might contribute to antifungal activity and/or that combination of the compounds results in a higher antifungal activity.
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Affiliation(s)
- Fernanda R Bresciani
- Postgraduate Program in Cellular and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Lucélia Santi
- Postgraduate Program in Cellular and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Experimental Research Center, Clinical Hospital of Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Walter O Beys-da-Silva
- Postgraduate Program in Cellular and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Experimental Research Center, Clinical Hospital of Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Markus Berger
- Experimental Research Center, Clinical Hospital of Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Vanessa de A Barcellos
- Postgraduate Program in Cellular and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Jan Schripsema
- Metabolomics Group, State University of North Fluminense Darcy Ribeiro, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Gilsane L von Poser
- Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Jorge A Guimarães
- Experimental Research Center, Clinical Hospital of Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Marilene H Vainstein
- Postgraduate Program in Cellular and Molecular Biology, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
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13
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Singh S, Fatima Z, Ahmad K, Hameed S. Repurposing of respiratory drug theophylline against Candida albicans: mechanistic insights unveil alterations in membrane properties and metabolic fitness. J Appl Microbiol 2020; 129:860-875. [PMID: 32320111 DOI: 10.1111/jam.14669] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 04/01/2020] [Accepted: 04/16/2020] [Indexed: 01/01/2023]
Abstract
AIMS Drug repurposing is an attractive chemotherapeutic strategy that serves to make up for the inadequacy of current antifungal drugs. The present study aims to repurpose theophylline (THP) against Candida albicans. THP is a methylxanthine derived from cocoa beans and tea extracts, generally used as the first-line drug for asthma and other respiratory disorders. METHODS AND RESULTS We investigated the antifungal activity of THP against C. albicans and non-albicans species. Mechanistic insights revealed that THP induces membrane damage. Enhanced ionic disturbances and depleted ergosterol levels with the concomitant rise in membrane fluidity due to elevated flippase activity confirmed the membrane damaging effect. THP impeded the metabolic adaptability of C. albicans by inhibiting malate synthase and isocitrate lyase enzymes of the glyoxylate cycle. In vivo efficacy of THP was depicted by increased survival of C. albicans infected Caenorhabditis elegans model. CONCLUSIONS This study elucidates the antifungal potential of THP with mechanistic insights. SIGNIFICANCE AND IMPACT OF THE STUDY This study unveils the antifungal potential of THP, a known respiratory drug that can be further utilized for a wider range of applications such as combating fungal infections. The effect of THP with the known antifungal drugs can be exploited in the combinatorial drug approach for treating candidiasis.
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Affiliation(s)
- S Singh
- Amity Institute of Biotechnology, Amity University Haryana, Gurugram (Manesar), India
| | - Z Fatima
- Amity Institute of Biotechnology, Amity University Haryana, Gurugram (Manesar), India
| | - K Ahmad
- Department of Pharmaceutical Chemistry, Jamia Hamdard, New Delhi, India
| | - S Hameed
- Amity Institute of Biotechnology, Amity University Haryana, Gurugram (Manesar), India
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14
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Sharma RK, Singh V, Tiwari N, Butcher R, Katiyar D. Synthesis, antimicrobial and chitinase inhibitory activities of 3-amidocoumarins. Bioorg Chem 2020; 98:103700. [DOI: 10.1016/j.bioorg.2020.103700] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 01/30/2020] [Accepted: 02/24/2020] [Indexed: 12/15/2022]
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15
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Chrissian C, Camacho E, Fu MS, Prados-Rosales R, Chatterjee S, Cordero RJB, Lodge JK, Casadevall A, Stark RE. Melanin deposition in two Cryptococcus species depends on cell-wall composition and flexibility. J Biol Chem 2020; 295:1815-1828. [PMID: 31896575 DOI: 10.1074/jbc.ra119.011949] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 12/31/2019] [Indexed: 12/14/2022] Open
Abstract
Cryptococcus neoformans and Cryptococcus gattii are two species complexes in the large fungal genus Cryptococcus and are responsible for potentially lethal disseminated infections. These two complexes share several phenotypic traits, such as production of the protective compound melanin. In C. neoformans, the pigment associates with key cellular constituents that are essential for melanin deposition within the cell wall. Consequently, melanization is modulated by changes in cell-wall composition or ultrastructure. However, whether similar factors influence melanization in C. gattii is unknown. Herein, we used transmission EM, biochemical assays, and solid-state NMR spectroscopy of representative isolates and "leaky melanin" mutant strains from each species complex to examine the compositional and structural factors governing cell-wall pigment deposition in C. neoformans and C. gattii. The principal findings were the following. 1) C. gattii R265 had an exceptionally high chitosan content compared with C. neoformans H99; a rich chitosan composition promoted homogeneous melanin distribution throughout the cell wall but did not increase the propensity of pigment deposition. 2) Strains from both species manifesting the leaky melanin phenotype had reduced chitosan content, which was compensated for by the production of lipids and other nonpolysaccharide constituents that depended on the species or mutation. 3) Changes in the relative rigidity of cell-wall chitin were associated with aberrant pigment retention, implicating cell-wall flexibility as an independent variable in cryptococcal melanin assembly. Overall, our results indicate that cell-wall composition and molecular architecture are critical factors for the anchoring and arrangement of melanin pigments in both C. neoformans and C. gattii species complexes.
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Affiliation(s)
- Christine Chrissian
- Department of Chemistry and Biochemistry, City College of New York and CUNY Institute for Macromolecular Assemblies, New York, New York 10031; Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, New York, New York 10016
| | - Emma Camacho
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205
| | - Man Shun Fu
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205
| | - Rafael Prados-Rosales
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10033; Department of Preventive Medicine and Public Health and Microbiology, Autonoma University of Madrid, 28049 Madrid, Spain
| | - Subhasish Chatterjee
- Department of Chemistry and Biochemistry, City College of New York and CUNY Institute for Macromolecular Assemblies, New York, New York 10031
| | - Radames J B Cordero
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205
| | - Jennifer K Lodge
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205
| | - Ruth E Stark
- Department of Chemistry and Biochemistry, City College of New York and CUNY Institute for Macromolecular Assemblies, New York, New York 10031; Ph.D. Program in Biochemistry, The Graduate Center of the City University of New York, New York, New York 10016; Ph.D. Program in Chemistry, The Graduate Center of the City University of New York, New York, New York 10016.
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16
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El-Bialy HA, El-Gamal MS, Elsayed MA, Saudi H, Khalifa M. Microbial melanin physiology under stress conditions and gamma radiation protection studies. Radiat Phys Chem Oxf Engl 1993 2019. [DOI: 10.1016/j.radphyschem.2019.05.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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17
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Camacho E, Vij R, Chrissian C, Prados-Rosales R, Gil D, O'Meally RN, Cordero RJB, Cole RN, McCaffery JM, Stark RE, Casadevall A. The structural unit of melanin in the cell wall of the fungal pathogen Cryptococcus neoformans. J Biol Chem 2019; 294:10471-10489. [PMID: 31118223 PMCID: PMC6615676 DOI: 10.1074/jbc.ra119.008684] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/19/2019] [Indexed: 11/06/2022] Open
Abstract
Melanins are synthesized macromolecules that are found in all biological kingdoms. These pigments have a myriad of roles that range from microbial virulence to key components of the innate immune response in invertebrates. Melanins also exhibit unique properties with potential applications in physics and material sciences, ranging from electrical batteries to novel therapeutics. In the fungi, melanins, such as eumelanins, are components of the cell wall that provide protection against biotic and abiotic elements. Elucidation of the smallest fungal cell wall-associated melanin unit that serves as a building block is critical to understand the architecture of these polymers, its interaction with surrounding components, and their functional versatility. In this study, we used isopycnic gradient sedimentation, NMR, EPR, high-resolution microscopy, and proteomics to analyze the melanin in the cell wall of the human pathogenic fungus Cryptococcus neoformans We observed that melanin is assembled into the cryptococcal cell wall in spherical structures ∼200 nm in diameter, termed melanin granules, which are in turn composed of nanospheres ∼30 nm in diameter, termed fungal melanosomes. We noted that melanin granules are closely associated with proteins that may play critical roles in the fungal melanogenesis and the supramolecular structure of this polymer. Using this structural information, we propose a model for C. neoformans' melanization that is similar to the process used in animal melanization and is consistent with the phylogenetic relatedness of the fungal and animal kingdoms.
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Affiliation(s)
- Emma Camacho
- From the Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, Maryland 21205
| | - Raghav Vij
- From the Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, Maryland 21205
| | - Christine Chrissian
- the Department of Chemistry and Biochemistry, City College of New York and CUNY Institute for Macromolecular Assemblies, New York, New York 10031, the City University of New York
- Ph.D. Programs in Biochemistry and
| | - Rafael Prados-Rosales
- the Department of Microbiology and Immunology, Albert Einstein College of Medicine, Yeshiva University, Bronx, New York 10461
- the CIC bioGUNE, 48160 Derio, Vizcaya, Spain
- the Department of Preventive Medicine and Public Health and Microbiology, Autonoma University of Madrid, 28049 Madrid, Spain
| | - David Gil
- the CIC bioGUNE, 48160 Derio, Vizcaya, Spain
| | - Robert N O'Meally
- the Johns Hopkins Mass Spectrometry and Proteomic Facility, The Johns Hopkins University, Baltimore, Maryland 21205, and
| | - Radames J B Cordero
- From the Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, Maryland 21205
| | - Robert N Cole
- the Johns Hopkins Mass Spectrometry and Proteomic Facility, The Johns Hopkins University, Baltimore, Maryland 21205, and
| | - J Michael McCaffery
- the Integrated Imaging Center, Department of Biology, Engineering in Oncology Center, and Institute for NanoBioTechnology, The Johns Hopkins University, Baltimore, Maryland 21218
| | - Ruth E Stark
- the Department of Chemistry and Biochemistry, City College of New York and CUNY Institute for Macromolecular Assemblies, New York, New York 10031, the City University of New York
- Ph.D. Programs in Biochemistry and
- Chemistry, New York, New York 10016
| | - Arturo Casadevall
- From the Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, Maryland 21205,
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18
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Synthesis, homology modeling, molecular docking, dynamics, and antifungal screening of new 4-hydroxycoumarin derivatives as potential chitinase inhibitors. J Mol Struct 2019. [DOI: 10.1016/j.molstruc.2018.11.099] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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19
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Tetreau G, Wang P. Chitinous Structures as Potential Targets for Insect Pest Control. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1142:273-292. [PMID: 31102251 DOI: 10.1007/978-981-13-7318-3_13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Chitinous structures are physiologically fundamental in insects. They form the insect exoskeleton, play important roles in physiological systems and provide physical, chemical and biological protections in insects. As critically important structures in insects, chitinous structures are attractive target sites for the development of new insect-pest-control strategies. Chitinous structures in insects are complex and their formation and maintenance are dynamically regulated with the growth and development of insects. In the past few decades, studies on insect chitinous structures have shed lights on the physiological functions, compositions, structural formation, and regulation of the chitinous structures. Current understanding of the chitinous structures has indicated opportunities for exploring new target sites for insect control. Mechanisms to disrupt chitinous structures in insects have been studied and strategies for the potential development of new means of insect control by targeting chitinous structures have been proposed and are practically to be explored.
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Affiliation(s)
- Guillaume Tetreau
- University of Grenoble Alpes, CNRS, CEA, IBS, 38000, Grenoble, France
| | - Ping Wang
- Department of Entomology, Cornell University, Geneva, NY, 14456, USA.
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20
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Perez-Dulzaides R, Camacho E, Cordero RJB, Casadevall A. Cell-wall dyes interfere with Cryptococcus neoformans melanin deposition. MICROBIOLOGY (READING, ENGLAND) 2018; 164:1012-1022. [PMID: 29939127 PMCID: PMC6152417 DOI: 10.1099/mic.0.000682] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Melanization is an intrinsic characteristic of many fungal species, but details of this process are poorly understood because melanins are notoriously difficult pigments to study. While studying the binding of cell-wall dyes, Eosin Y or Uvitex, to melanized and non-melanized Cryptococcus neoformans cells we noted that melanization leads to reduced fluorescence intensity, suggesting that melanin interfered with dye binding to the cell wall. The growth of C. neoformans in melanizing conditions with either of the cell-wall dyes resulted in an increase in supernatant-associated melanin, consistent with blockage of melanin attachment to the cell wall. This effect provided the opportunity to characterize melanin released into culture supernatants. Released melanin particles appeared mostly as networked structures having dimensions consistent with previously described extracellular vesicles. Hence, dye binding to the cell wall created conditions that resembled the 'leaky melanin' phenotype described for certain cell-wall mutants. In agreement with earlier studies on fungal melanins biosynthesis, our observations are supportive of a model whereby C. neoformans melanization proceeds by the attachment of melanin nanoparticles to the cell wall through chitin, chitosan, and various glucans.
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Affiliation(s)
- Ricardo Perez-Dulzaides
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Emma Camacho
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Radames J. B. Cordero
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA,*Correspondence: Arturo Casadevall,
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21
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Monteiro J, Alves MG, Oliveira PF, Silva BM. Pharmacological potential of methylxanthines: Retrospective analysis and future expectations. Crit Rev Food Sci Nutr 2018; 59:2597-2625. [PMID: 29624433 DOI: 10.1080/10408398.2018.1461607] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Methylated xanthines (methylxanthines) are available from a significant number of different botanical species. They are ordinarily included in daily diet, in many extremely common beverages and foods. Caffeine, theophylline and theobromine are the main methylxanthines available from natural sources. The supposedly relatively low toxicity of methylxanthines, combined with the many beneficial effects that have been attributed to these compounds through time, generated a justified attention and a very prolific ground for dedicated scientific reports. Methylxanthines have been widely used as therapeutical tools, in an intriguing range of medicinal scopes. In fact, methylxanthines have been/were medically used as Central Nervous System stimulants, bronchodilators, coronary dilators, diuretics and anti-cancer adjuvant treatments. Other than these applications, methylxanthines have also been hinted to hold other beneficial health effects, namely regarding neurodegenerative diseases, cardioprotection, diabetes and fertility. However, it seems now consensual that toxicity concerns related to methylxanthine consumption and/or therapeutic use should not be dismissed. Taking all the knowledge and expectations on the potential of methylxanthines into account, we propose a systematic look at the past and future of methylxanthine pharmacologic applications, discussing all the promise and anticipating possible constraints. Anyways, methylxanthines will still substantiate considerable meaningful research and discussion for years to come.
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Affiliation(s)
- João Monteiro
- Mass Spectrometry Centre, Department of Chemistry & CESAM, University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal
| | - Marco G Alves
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto , Porto , Portugal
| | - Pedro F Oliveira
- Department of Microscopy, Laboratory of Cell Biology, Unit for Multidisciplinary Research in Biomedicine (UMIB), Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto , Porto , Portugal.,Institute of Health Research an Innovation (i3S), University of Porto , Porto , Portugal
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22
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Borowiecki P, Wińska P, Bretner M, Gizińska M, Koronkiewicz M, Staniszewska M. Synthesis of novel proxyphylline derivatives with dual Anti-Candida albicans and anticancer activity. Eur J Med Chem 2018. [PMID: 29533875 DOI: 10.1016/j.ejmech.2018.02.077] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Three out of 16 newly synthesized 1,3-dimethylxanthine derivatives (proxyphylline analogues) exhibited consistencies between antifungal and anticancer properties. Proxyphylline possessing 1-(10H-phenothiazin-10-yl)propan-2-yl (6) and polybrominated benzimidazole (41) or benzotriazole moiety (42) remained selectively cidal against Candida albicans (lg R ≥ 3 at conc. of 31, 36 and 20 μM, respectively) however not against normal mammalian Vero cell line in vitro (IC50 ≥ 280 μM) and Galleria mellonella in vivo. These compounds also displayed moderate antineoplastic activity against human breast adenocarcinoma (MCF-7) cell line (EC50 = 80 μM) and high against peripheral blood T lymphoblast (CCRF-CEM) (EC50 = 6.3-6.5 μM). In addition, 6 and 42 exerted: (1) dual activity against fungal adhesion and damage mature biofilm; (2) necrosis of planktonic cells due to loss of membrane function and of structural integrity; (3) biochemical (inhibition of sessile cell respiration) and morphological changes in cell wall polysaccharide contents. Therefore, leading proxyphylline derivatives can be employed to prevent cancer-associated biofilm Candida infections.
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Affiliation(s)
- Paweł Borowiecki
- Warsaw University of Technology, Faculty of Chemistry, Noakowskiego 3, 00-664 Warsaw, Poland.
| | - Patrycja Wińska
- Warsaw University of Technology, Faculty of Chemistry, Noakowskiego 3, 00-664 Warsaw, Poland
| | - Maria Bretner
- Warsaw University of Technology, Faculty of Chemistry, Noakowskiego 3, 00-664 Warsaw, Poland
| | - Małgorzata Gizińska
- National Institute of Public Health-National Institute of Hygiene, Chocimska 24, 00-791 Warsaw, Poland
| | | | - Monika Staniszewska
- National Institute of Public Health-National Institute of Hygiene, Chocimska 24, 00-791 Warsaw, Poland.
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23
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Sephton-Clark PCS, Voelz K. Spore Germination of Pathogenic Filamentous Fungi. ADVANCES IN APPLIED MICROBIOLOGY 2017; 102:117-157. [PMID: 29680124 DOI: 10.1016/bs.aambs.2017.10.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Fungi, algae, plants, protozoa, and bacteria are all known to form spores, especially hardy and ubiquitous propagation structures that are also often the infectious agents of diseases. Spores can survive for thousands of years, frozen in the permafrost (Kochkina et al., 2012), with the oldest viable spores extracted after 250 million years from salt crystals (Vreeland, Rosenzweig, & Powers, 2000). Their resistance to high levels of UV, desiccation, pressure, heat, and cold enables the survival of spores in the harshest conditions (Setlow, 2016). For example, Bacillus subtilis spores can survive and remain viable after experiencing conditions similar to those on Mars (Horneck et al., 2012). Spores are disseminated through environmental factors. Wind, water, or animal carriage allow spores to be spread ubiquitously throughout the environment. Spores will break dormancy and begin to germinate once exposed to favorable conditions. Germination is the mechanism that converts the spore from a dormant biological organism to one that grows vegetatively and is capable of either sexual or asexual reproduction. The process of germination has been well studied in plants, moss, bacteria, and many fungi (Hohe & Reski, 2005; Huang & Hull, 2017; Vesty et al., 2016). Unfortunately, information on the complex signaling involved in the regulation of germination, particularly in fungi remains lacking. This chapter will discuss germination of fungal spores covering our current understanding of the regulation, signaling, outcomes, and implications of germination of pathogenic fungal spores. Owing to the morphological similarities between the spore-hyphal and yeast-hyphal transition and their relevance for disease progression, relevant aspects of fungal dimorphism will be discussed alongside spore germination in this chapter.
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Affiliation(s)
- Poppy C S Sephton-Clark
- School of Biosciences, Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Kerstin Voelz
- School of Biosciences, Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom.
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Abstract
Melanins are ancient biological pigments found in all kingdoms of life. In fungi, their role in microbial pathogenesis is well established; however, these complex biomolecules also confer upon fungal microorganisms the faculty to tolerate extreme environments such as the Earth's poles, the International Space Station and places contaminated by toxic metals and ionizing radiation. A remarkable property of melanin is its capacity to interact with a wide range of electromagnetic radiation frequencies, functioning as a protecting and energy harvesting pigment. Other roles of fungal melanin include scavenging of free radical, thermo-tolerance, metal ion sequestration, cell development, and mechanical-chemical cellular strength. In this review, we explore the various functions ascribed to this biological pigment in fungi and its remarkable physicochemical properties.
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Affiliation(s)
- Radames JB Cordero
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205
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Nosanchuk JD, Stark RE, Casadevall A. Fungal Melanin: What do We Know About Structure? Front Microbiol 2015; 6:1463. [PMID: 26733993 PMCID: PMC4687393 DOI: 10.3389/fmicb.2015.01463] [Citation(s) in RCA: 157] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 12/07/2015] [Indexed: 12/22/2022] Open
Abstract
The production of melanin significantly enhances the virulence of many important human pathogenic fungi. Despite fungal melanin’s importance in human disease, as well as melanin’s contribution to the ability of fungi to survive in diverse hostile environments, the structure of melanin remains unsolved. Nevertheless, ongoing research efforts have progressively revealed several notable structural characteristics of this enigmatic pigment, which will be the focus of this review. These compositional and organizational insights could further our ability to develop novel therapeutic approaches to combat fungal disease and enhance our understanding of how melanin is inserted into the cell wall.
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Affiliation(s)
- Joshua D Nosanchuk
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of MedicineBronx, NY, USA; Microbiology and Immunology, Albert Einstein College of MedicineBronx, NY, USA
| | - Ruth E Stark
- Department of Chemistry and Biochemistry, The Graduate Center, The City College of New York, The City University of New YorkNew York, NY, USA; Institute for Macromolecular Assemblies, The City University of New YorkNew York, NY, USA
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University Baltimore, MD, USA
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Pentoxifylline immunomodulation in the treatment of experimental chronic pulmonary paracoccidioidomycosis. FIBROGENESIS & TISSUE REPAIR 2015; 8:10. [PMID: 26034509 PMCID: PMC4450470 DOI: 10.1186/s13069-015-0027-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 05/07/2015] [Indexed: 11/25/2022]
Abstract
Background Pentoxifylline (PTX) is a methylxanthine compound with immunomodulatory and antifibrotic properties. The simultaneous use of PTX and antifungal therapy (itraconazole) has previously been evaluated in an experimental model of pulmonary paracoccidioidomycosis (PCM), a systemic fungal disease caused by the fungus Paracoccidioides brasiliensis (Pb) and characterized by chronic inflammation and lung fibrosis that appears even after a successful course of antifungal therapy. The results revealed prompt and statistically significant reductions in inflammation and fibrosis when compared to itraconazole alone. However, the effect of monotherapy with PTX on the host response to PCM has not been well-documented. Our aim was to determine the effect of PTX on the course of pulmonary lesions and on the local immune response. Results At the middle and end of treatment, the Pb-infected-PTX-treated mice exhibited significant reductions in lung density compared to the Pb-infected-non-treated mice as assessed by the quantification of Hounsfield units on high-resolution computed tomography (HRCT) (p <0.05 by Kruskal-Wallis test); additionally, at the end of therapy, the lung areas involved in the inflammatory reactions were only 3 vs. 22 %, respectively, by histomorphometry (p <0.05 by Mann–Whitney test), and this reduction was associated with a lower fungal burden and limited collagen increment in the pulmonary lesions. PTX treatment restored the levels of IFN-γ, MIP-1β, and IL-3 that had been down-regulated by Pb infection. Additionally, IL-12p70, IL-10, IL-13, and eotaxin were significantly increased, whereas Regulated upon Activation, Normal T cell Expressed and Secreted (RANTES) levels were decreased in the lungs of the Pb-infected-PTX-treated mice compared to the non-treated group. Conclusions/significance This study showed that PTX therapy administered at an “early” stage of granulomatous inflammation controlled the progress of the PCM by diminishing the pulmonary inflammation and the fungal burden and avoiding the appearance of collagen deposits in the pulmonary lesions.
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Yoo Y, Choi HT. Antifungal chitinase against human pathogenic yeasts from Coprinellus congregatus. J Microbiol 2014; 52:441-3. [PMID: 24535739 DOI: 10.1007/s12275-014-3257-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 08/24/2013] [Accepted: 09/09/2013] [Indexed: 11/26/2022]
Abstract
The inky cap, Coprinellus congregatus, produces mushrooms which become autolyzed rapidly to generate black liquid droplets, in which no cell wall is detected by microscopy. A chitinase (Chi2) which is synthesized during the autolytic phase of C. congregatus inhibits the growths of Candida albicans and Cryptococcus neoformans up to 10% at the concentration of 10 μg/ml, about 50% at concentration of 20 μg/ml, and up to 95% at the concentration of 70 μg/ml. Upon treatment these yeast cells are observed to be severely deformed, with the formation of large holes in the cell wall. The two yeast species show no growth inhibition at the concentration of 5 μg/ml, which means the minimum inhibitory concentrations for both yeast species are 10 μg/ml under these experimental conditions.
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Affiliation(s)
- Yeeun Yoo
- Department of Biochemistry, Kangwon National University, Chunchon, 200-701, Republic of Korea
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Adrangi S, Faramarzi MA. From bacteria to human: a journey into the world of chitinases. Biotechnol Adv 2013; 31:1786-95. [PMID: 24095741 DOI: 10.1016/j.biotechadv.2013.09.012] [Citation(s) in RCA: 136] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 09/26/2013] [Accepted: 09/28/2013] [Indexed: 12/28/2022]
Abstract
Chitinases, the enzymes responsible for the biological degradation of chitin, are found in a wide range of organisms from bacteria to higher plants and animals. They participate in numerous physiological processes such as nutrition, parasitism, morphogenesis and immunity. Many organisms, in addition to chitinases, produce inactive chitinase-like lectins that despite lacking enzymatic activity are involved in several regulatory functions. Most known chitinases belong to families 18 and 19 of glycosyl hydrolases, however a few chitinases that belong to families 23 and 48 have also been identified in recent years. In this review, different aspects of chitinases and chi-lectins from bacteria, fungi, insects, plants and mammals are discussed.
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Affiliation(s)
- Sina Adrangi
- Department of Pharmaceutical Biotechnology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Abstract
Biological control of phytopathogenic fungi and insects continues to inspire the research and development of environmentally friendly bioactive alternatives. Potentially lytic enzymes, chitinases can act as a biocontrol agent against agriculturally important fungi and insects. The cell wall in fungi and protective covers, i.e. cuticle in insects shares a key structural polymer, chitin, a β-1,4-linked N-acetylglucosamine polymer. Therefore, it is advantageous to develop a common biocontrol agent against both of these groups. As chitin is absent in plants and mammals, targeting its metabolism will signify an eco-friendly strategy for the control of agriculturally important fungi and insects but is innocuous to mammals, plants, beneficial insects and other organisms. In addition, development of chitinase transgenic plant varieties probably holds the most promising method for augmenting agricultural crop protection and productivity, when properly integrated into traditional systems. Recently, human proteins with chitinase activity and chitinase-like proteins were identified and established as biomarkers for human diseases. This review covers the recent advances of chitinases as a biocontrol agent and its various applications including preparation of medically important chitooligosaccharides, bioconversion of chitin as well as in implementing chitinases as diagnostic and prognostic markers for numerous diseases and the prospect of their future utilization.
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Affiliation(s)
- Anand Nagpure
- University School of Biotechnology, Guru Gobind Singh Indraprastha University , New Delhi , India
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Chitin-like molecules associate with Cryptococcus neoformans glucuronoxylomannan to form a glycan complex with previously unknown properties. EUKARYOTIC CELL 2012; 11:1086-94. [PMID: 22562469 DOI: 10.1128/ec.00001-12] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In prior studies, we demonstrated that glucuronoxylomannan (GXM), the major capsular polysaccharide of the fungal pathogen Cryptococcus neoformans, interacts with chitin oligomers at the cell wall-capsule interface. The structural determinants regulating these carbohydrate-carbohydrate interactions, as well as the functions of these structures, have remained unknown. In this study, we demonstrate that glycan complexes composed of chitooligomers and GXM are formed during fungal growth and macrophage infection by C. neoformans. To investigate the required determinants for the assembly of chitin-GXM complexes, we developed a quantitative scanning electron microscopy-based method using different polysaccharide samples as inhibitors of the interaction of chitin with GXM. This assay revealed that chitin-GXM association involves noncovalent bonds and large GXM fibers and depends on the N-acetyl amino group of chitin. Carboxyl and O-acetyl groups of GXM are not required for polysaccharide-polysaccharide interactions. Glycan complex structures composed of cryptococcal GXM and chitin-derived oligomers were tested for their ability to induce pulmonary cytokines in mice. They were significantly more efficient than either GXM or chitin oligomers alone in inducing the production of lung interleukin 10 (IL-10), IL-17, and tumor necrosis factor alpha (TNF-α). These results indicate that association of chitin-derived structures with GXM through their N-acetyl amino groups generates glycan complexes with previously unknown properties.
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