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Kavroumatzi CK, Boutsika A, Ortega P, Zambounis A, Tsitsigiannis DI. Unlocking the Transcriptional Reprogramming Repertoire between Variety-Dependent Responses of Grapevine Berries to Infection by Aspergillus carbonarius. PLANTS (BASEL, SWITZERLAND) 2024; 13:2043. [PMID: 39124161 PMCID: PMC11314482 DOI: 10.3390/plants13152043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2024] [Revised: 07/20/2024] [Accepted: 07/21/2024] [Indexed: 08/12/2024]
Abstract
Aspergillus carbonarius causes severe decays on berries in vineyards and is among the main fungal species responsible for grape contamination by ochratoxin A (OTA), which is the foremost mycotoxin produced by this fungus. The main goal of this study was to investigate at the transcriptome level the comparative profiles between two table grape varieties (Victoria and Fraoula, the white and red variety, respectively) after their inoculation with a virulent OTA-producing A. carbonarius strain. The two varieties revealed quite different transcriptomic signatures and the expression profiles of the differential expressed genes (DEGs) highlighted distinct and variety-specific responses during the infection period. The significant enrichment of pathways related to the modulation of transcriptional dynamics towards the activation of defence responses, the triggering of the metabolic shunt for the biosynthesis of secondary metabolites, mainly phenylpropanoids, and the upregulation of DEGs encoding phytoalexins, transcription factors, and genes involved in plant-pathogen interaction and immune signaling transduction was revealed in an early time point in Fraoula, whereas, in Victoria, any transcriptional reprogramming was observed after a delay. However, both varieties, to some extent, also showed common expression dynamics for specific DEG families, such as those encoding for laccases and stilbene synthases. Jasmonate (JA) may play a critical modulator role in the defence machinery as various JA-biosynthetic DEGs were upregulated. Along with the broader modulation of the transcriptome that was observed in white grape, expression profiles of specific A. carbonarius genes related to pathogenesis, fungal sporulation, and conidiation highlight the higher susceptibility of Victoria. Furthermore, the A. carbonarius transcriptional patterns directly associated with the regulation of the pathogen OTA-biosynthesis gene cluster were more highly induced in Victoria than in Fraoula. The latter was less contaminated by OTA and showed substantially lower sporulation. These findings contribute to uncovering the interplay beyond this plant-microbe interaction.
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Affiliation(s)
- Charikleia K. Kavroumatzi
- Laboratory of Plant Pathology, Department of Crop Science, Agricultural University of Athens, 11855 Athens, Greece; (C.K.K.); (P.O.)
- Hellenic Agricultural Organization—DIMITRA (ELGO—DIMITRA), Institute of Plant Breeding and Genetic Resources, 57001 Thessaloniki, Greece; (A.B.); (A.Z.)
| | - Anastasia Boutsika
- Hellenic Agricultural Organization—DIMITRA (ELGO—DIMITRA), Institute of Plant Breeding and Genetic Resources, 57001 Thessaloniki, Greece; (A.B.); (A.Z.)
| | - Paula Ortega
- Laboratory of Plant Pathology, Department of Crop Science, Agricultural University of Athens, 11855 Athens, Greece; (C.K.K.); (P.O.)
- Department of Agro-Food Engineering and Biotechnology, Universitat Politècnica de Catalunya, 08860 Castelldefels, Spain
| | - Antonios Zambounis
- Hellenic Agricultural Organization—DIMITRA (ELGO—DIMITRA), Institute of Plant Breeding and Genetic Resources, 57001 Thessaloniki, Greece; (A.B.); (A.Z.)
| | - Dimitrios I. Tsitsigiannis
- Laboratory of Plant Pathology, Department of Crop Science, Agricultural University of Athens, 11855 Athens, Greece; (C.K.K.); (P.O.)
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Llobregat B, González-Candelas L, Ballester AR. Exploring the Biocontrol Capability of Non-Mycotoxigenic Strains of Penicillium expansum. Toxins (Basel) 2024; 16:52. [PMID: 38251268 PMCID: PMC10820982 DOI: 10.3390/toxins16010052] [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: 12/07/2023] [Revised: 01/09/2024] [Accepted: 01/14/2024] [Indexed: 01/23/2024] Open
Abstract
Penicillium expansum is one the major postharvest pathogens of pome fruit during postharvest handling and storage. This fungus also produces patulin, which is a highly toxic mycotoxin that can contaminate infected fruits and their derived products and whose levels are regulated in many countries. In this study, we investigated the biocontrol potential of non-mycotoxigenic strains of Penicillium expansum against a mycotoxigenic strain. We analyzed the competitive behavior of two knockout mutants that were unable to produce patulin. The first mutant (∆patK) involved the deletion of the patK gene, which is the initial gene in patulin biosynthesis. The second mutant (∆veA) involved the deletion of veA, which is a global regulator of primary and secondary metabolism. At the phenotypic level, the ∆patK mutant exhibited similar phenotypic characteristics to the wild-type strain. In contrast, the ∆veA mutant displayed altered growth characteristics compared with the wild type, including reduced conidiation and abnormal conidiophores. Neither mutant produced patulin under the tested conditions. Under various stress conditions, the ∆veA mutants exhibited reduced growth and conidiation when exposed to stressors, including cell membrane stress, oxidative stress, osmotic stress, and different pH values. However, no significant changes were observed in the ∆patK mutant. In competitive growth experiments, the presence of non-mycotoxigenic strains reduced the population of the wild-type strain during in vitro growth. Furthermore, the addition of either of the non-mycotoxigenic strains resulted in a significant decrease in patulin levels. Overall, our results suggest the potential use of non-mycotoxigenic mutants, particularly ∆patK mutants, as biocontrol agents to reduce patulin contamination in food and feed.
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Affiliation(s)
| | | | - Ana-Rosa Ballester
- Instituto de Agroquímica y Tecnología de Alimentos (IATA), CSIC, Calle Catedrático Agustín Escardino 7, 46980 Paterna, Spain; (B.L.); (L.G.-C.)
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Ochratoxin A Defective Aspergillus carbonarius Mutants as Potential Biocontrol Agents. Toxins (Basel) 2022; 14:toxins14110745. [PMID: 36355995 PMCID: PMC9695793 DOI: 10.3390/toxins14110745] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 10/27/2022] [Accepted: 10/28/2022] [Indexed: 11/06/2022] Open
Abstract
Aspergillus carbonarius is one of the main species responsible for wine, coffee and cocoa toxin contamination. The main mycotoxin produced by this fungus, ochratoxin A (OTA), is a secondary metabolite categorized as a possible carcinogen because of its significant nephrotoxicity and immunosuppressive effects. A polyketide synthase gene (otaA) encodes the first enzyme in the OTA biosynthetic pathway. It is known that the filamentous fungi, growth, development and production of secondary metabolites are interconnected processes governed by global regulatory factors whose encoding genes are generally located outside the gene clusters involved in the biosynthesis of each secondary metabolite, such as the veA gene, which forms part of the VELVET complex. Different fungal strains compete for nutrients and space when they infect their hosts, and safer non-mycotoxigenic strains may be able to outcompete mycotoxigenic strains during colonization. To determine the possible utility of biopesticides based on the competitive exclusion of mycotoxigenic strains by non-toxigenic ones, we used A. carbonarius ΔotaA and ΔveA knockout mutants. Our results showed that during both in vitro growth and infection of grapes, non-mycotoxigenic strains could outcompete the wild-type strain. Additionally, the introduction of the non-mycotoxigenic strain led to a drastic decrease in OTA during both in vitro growth and infection of grapes.
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Yang F, Cheng L, Du Y, Xia L, Long CA. Functional identification of the DHN melanin synthesis gene cluster and its role in UV-C tolerance in citrus postharvest pathogenic fungus Penicillium digitatum. Fungal Biol 2022; 126:566-575. [DOI: 10.1016/j.funbio.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 07/11/2022] [Indexed: 11/28/2022]
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Pola-Sánchez E, Villalobos-Escobedo JM, Carreras-Villaseñor N, Martínez-Hernández P, Beltrán-Hernández EB, Esquivel-Naranjo EU, Herrera-Estrella A. A Global Analysis of Photoreceptor-Mediated Transcriptional Changes Reveals the Intricate Relationship Between Central Metabolism and DNA Repair in the Filamentous Fungus Trichoderma atroviride. Front Microbiol 2021; 12:724676. [PMID: 34566928 PMCID: PMC8456097 DOI: 10.3389/fmicb.2021.724676] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/10/2021] [Indexed: 12/13/2022] Open
Abstract
Light provides critical information for the behavior and development of basically all organisms. Filamentous fungi sense blue light, mainly, through a unique transcription factor complex that activates its targets in a light-dependent manner. In Trichoderma atroviride, the BLR-1 and BLR-2 proteins constitute this complex, which triggers the light-dependent formation of asexual reproduction structures (conidia). We generated an ENVOY photoreceptor mutant and performed RNA-seq analyses in the mutants of this gene and in those of the BLR-1, CRY-1 and CRY-DASH photoreceptors in response to a pulse of low intensity blue light. Like in other filamentous fungi BLR-1 appears to play a central role in the regulation of blue-light responses. Phenotypic characterization of the Δenv-1 mutant showed that ENVOY functions as a growth and conidiation checkpoint, preventing exacerbated light responses. Similarly, we observed that CRY-1 and CRY-DASH contribute to the typical light-induced conidiation response. In the Δenv-1 mutant, we observed, at the transcriptomic level, a general induction of DNA metabolic processes and strong repression of central metabolism. An analysis of the expression level of DNA repair genes showed that they increase their expression in the absence of env-1. Consistently, photoreactivation experiments showed that Δenv-1 had increased DNA repair capacity. Our results indicate that light perception in T. atroviride is far more complex than originally thought.
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Affiliation(s)
- Enrique Pola-Sánchez
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, Mexico
| | - José Manuel Villalobos-Escobedo
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, Mexico
| | | | - Pedro Martínez-Hernández
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, Mexico
| | - Emma Beatriz Beltrán-Hernández
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, Mexico
| | - Edgardo Ulises Esquivel-Naranjo
- Laboratorio de Microbiología Molecular, Unidad de Microbiología Básica y Aplicada, Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, Querétaro, Mexico
| | - Alfredo Herrera-Estrella
- Laboratorio Nacional de Genómica para la Biodiversidad-Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, Mexico
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Lim S, Bijlani S, Blachowicz A, Chiang YM, Lee MS, Torok T, Venkateswaran K, Wang CCC. Identification of the pigment and its role in UV resistance in Paecilomyces variotii, a Chernobyl isolate, using genetic manipulation strategies. Fungal Genet Biol 2021; 152:103567. [PMID: 33989788 DOI: 10.1016/j.fgb.2021.103567] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 01/18/2021] [Accepted: 01/26/2021] [Indexed: 11/19/2022]
Abstract
Fungi produce secondary metabolites that are not directly involved in their growth, but often contribute to their adaptation to extreme environmental stimuli and enable their survival. Conidial pigment or melanin is one of the secondary metabolites produced naturally by a polyketide synthesis (PKS) gene cluster in several filamentous fungi and is known to protect these fungi from extreme radiation conditions. Several pigmented or melanized fungi have been shown to grow under extreme radiation conditions at the Chernobyl nuclear accident site. Some of these fungi, including Paecilomyces variotii, were observed to grow towards the source of radiation. Therefore, in this study, we wanted to identify if the pigment produced by P. variotii, contributes to providing protection against radiation condition. We first identified the PKS gene responsible for synthesis of pigment in P. variotii and confirmed its role in providing protection against UV irradiation through CRISPR-Cas9 mediated gene deletion. This is the first report that describes the use of CRISPR methodology to create gene deletions in P. variotii. Further, we showed that the pigment produced by this fungus, was not inhibited by DHN-melanin pathway inhibitors, indicating that the fungus does not produce melanin. We then identified the pigment synthesized by the PKS gene of P. variotii, as a naptho-pyrone Ywa1, by heterologously expressing the gene in Aspergillus nidulans. The results obtained will further aid in understanding the mechanistic basis of radiation resistance.
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Affiliation(s)
- Sujeung Lim
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Swati Bijlani
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Adriana Blachowicz
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States; Biotechnology and Planetary Protection Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
| | - Yi-Ming Chiang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Ming-Shian Lee
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Tamas Torok
- Ecology Department, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Kasthuri Venkateswaran
- Biotechnology and Planetary Protection Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
| | - Clay C C Wang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States; Department of Chemistry, Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, CA, United States.
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Gerin D, Garrapa F, Ballester AR, González-Candelas L, De Miccolis Angelini RM, Faretra F, Pollastro S. Functional Role of Aspergillus carbonariusAcOTAbZIP Gene, a bZIP Transcription Factor within the OTA Gene Cluster. Toxins (Basel) 2021; 13:111. [PMID: 33540740 PMCID: PMC7913050 DOI: 10.3390/toxins13020111] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 12/15/2022] Open
Abstract
Aspergillus carbonarius is the principal fungal species responsible for ochratoxin A (OTA) contamination of grapes and derived products in the main viticultural regions worldwide. In recent years, co-expressed genes representing a putative-OTA gene cluster were identified, and the deletion of a few of them allowed the partial elucidation of the biosynthetic pathway in the fungus. In the putative OTA-gene cluster is additionally present a bZIP transcription factor (AcOTAbZIP), and with this work, A. carbonarius ΔAcOTAbZIP strains were generated to study its functional role. According to phylogenetic analysis, the gene is conserved in the OTA-producing fungi. A Saccharomyces cerevisiae transcription factor binding motif (TFBM) homolog, associated with bZIP transcription factors was present in the A. carbonarius OTA-gene cluster no-coding regions. AcOTAbZIP deletion results in the loss of OTA and the intermediates OTB and OTβ. Additionally, in ΔAcOTAbZIP strains, a down-regulation of AcOTApks, AcOTAnrps, AcOTAp450, and AcOTAhal genes was observed compared to wild type (WT). These results provide evidence of the direct involvement of the AcOTAbZIP gene in the OTA biosynthetic pathway by regulating the involved genes. The loss of OTA biosynthesis ability does not affect fungal development as demonstrated by the comparison of ΔAcOTAbZIP strains and WT strains in terms of vegetative growth and asexual sporulation on three different media. Finally, no statistically significant differences in virulence were observed among ΔAcOTAbZIP strains and WT strains on artificially inoculated grape berries, demonstrating that OTA is not required by A. carbonarius for the pathogenicity process.
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Affiliation(s)
- Donato Gerin
- Department of Soil, Plant and Food Sciences, University of Bari Aldo Moro, Via Giovanni Amendola, 165/A, 70126 Bari, Italy; (D.G.); (F.G.); (F.F.); (S.P.)
| | - Federica Garrapa
- Department of Soil, Plant and Food Sciences, University of Bari Aldo Moro, Via Giovanni Amendola, 165/A, 70126 Bari, Italy; (D.G.); (F.G.); (F.F.); (S.P.)
| | - Ana-Rosa Ballester
- Food Biotechnology Department, Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Calle Catedrático Agustín Escardino 7, 46980 Paterna, Valencia, Spain; (A.-R.B.); (L.G.-C.)
| | - Luis González-Candelas
- Food Biotechnology Department, Instituto de Agroquímica y Tecnología de Alimentos (IATA-CSIC), Calle Catedrático Agustín Escardino 7, 46980 Paterna, Valencia, Spain; (A.-R.B.); (L.G.-C.)
| | - Rita Milvia De Miccolis Angelini
- Department of Soil, Plant and Food Sciences, University of Bari Aldo Moro, Via Giovanni Amendola, 165/A, 70126 Bari, Italy; (D.G.); (F.G.); (F.F.); (S.P.)
- SELGE Network of Public Research Laboratories, Via Amendola, 165/A, 70126 Bari, Italy
| | - Francesco Faretra
- Department of Soil, Plant and Food Sciences, University of Bari Aldo Moro, Via Giovanni Amendola, 165/A, 70126 Bari, Italy; (D.G.); (F.G.); (F.F.); (S.P.)
- SELGE Network of Public Research Laboratories, Via Amendola, 165/A, 70126 Bari, Italy
| | - Stefania Pollastro
- Department of Soil, Plant and Food Sciences, University of Bari Aldo Moro, Via Giovanni Amendola, 165/A, 70126 Bari, Italy; (D.G.); (F.G.); (F.F.); (S.P.)
- SELGE Network of Public Research Laboratories, Via Amendola, 165/A, 70126 Bari, Italy
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Ambrico PF, Šimek M, Rotolo C, Morano M, Minafra A, Ambrico M, Pollastro S, Gerin D, Faretra F, De Miccolis Angelini RM. Surface Dielectric Barrier Discharge plasma: a suitable measure against fungal plant pathogens. Sci Rep 2020; 10:3673. [PMID: 32111863 PMCID: PMC7048822 DOI: 10.1038/s41598-020-60461-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 02/03/2020] [Indexed: 01/08/2023] Open
Abstract
Fungal diseases seriously affect agricultural production and the food industry. Crop protection is usually achieved by synthetic fungicides, therefore more sustainable and innovative technologies are increasingly required. The atmospheric pressure low-temperature plasma is a novel suitable measure. We report on the effect of plasma treatment on phytopathogenic fungi causing quantitative and qualitative losses of products both in the field and postharvest. We focus our attention on the in vitro direct inhibitory effect of non-contact Surface Dielectric Barrier Discharge on conidia germination of Botrytis cinerea, Monilinia fructicola, Aspergillus carbonarius and Alternaria alternata. A few minutes of treatment was required to completely inactivate the fungi on an artificial medium. Morphological analysis of spores by Scanning Electron Microscopy suggests that the main mechanism is plasma etching due to Reactive Oxygen Species or UV radiation. Spectroscopic analysis of plasma generated in humid air gives the hint that the rotational temperature of gas should not play a relevant role being very close to room temperature. In vivo experiments on artificially inoculated cherry fruits demonstrated that inactivation of fungal spores by the direct inhibitory effect of plasma extend their shelf life. Pre-treatment of fruits before inoculation improve the resistance to infections maybe by activating defense responses in plant tissues.
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Affiliation(s)
- Paolo F Ambrico
- Consiglio Nazionale delle Ricerche, Istituto per la Scienza e la Tecnologia dei Plasmi, via Amendola 122/D, 70126, Bari, Italy.
| | - Milan Šimek
- Academy of Sciences of the Czech Republic, Institute of Plasma Physics v.v.i., Department of Pulse Plasma Systems, Za Slovankou 1782/3, 18200, Prague, Czech Republic
| | - Caterina Rotolo
- Department of Soil, Plant and Food Sciences, University of Bari ALDO MORO, via G. Amendola 165/A, 70126, Bari, Italy
| | - Massimo Morano
- Department of Soil, Plant and Food Sciences, University of Bari ALDO MORO, via G. Amendola 165/A, 70126, Bari, Italy
| | - Angelantonio Minafra
- Consiglio Nazionale delle Ricerche, Istituto per la Protezione Sostenibile delle Piante, via Amendola 122/D, 70126, Bari, Italy
| | - Marianna Ambrico
- Consiglio Nazionale delle Ricerche, Istituto per la Scienza e la Tecnologia dei Plasmi, via Amendola 122/D, 70126, Bari, Italy
| | - Stefania Pollastro
- Department of Soil, Plant and Food Sciences, University of Bari ALDO MORO, via G. Amendola 165/A, 70126, Bari, Italy
| | - Donato Gerin
- Department of Soil, Plant and Food Sciences, University of Bari ALDO MORO, via G. Amendola 165/A, 70126, Bari, Italy
| | - Francesco Faretra
- Department of Soil, Plant and Food Sciences, University of Bari ALDO MORO, via G. Amendola 165/A, 70126, Bari, Italy.
| | - Rita M De Miccolis Angelini
- Department of Soil, Plant and Food Sciences, University of Bari ALDO MORO, via G. Amendola 165/A, 70126, Bari, Italy
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Chang PK, Cary JW, Lebar MD. Biosynthesis of conidial and sclerotial pigments in Aspergillus species. Appl Microbiol Biotechnol 2020; 104:2277-2286. [PMID: 31974722 DOI: 10.1007/s00253-020-10347-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 12/19/2019] [Accepted: 01/03/2020] [Indexed: 11/27/2022]
Abstract
Fungal pigments, which are classified as secondary metabolites, are polymerized products derived mostly from phenolic precursors with remarkable structural diversity. Pigments of conidia and sclerotia serve myriad functions. They provide tolerance against various environmental stresses such as ultraviolet light, oxidizing agents, and ionizing radiation. Some pigments even play a role in fungal pathogenesis. This review gathers available research and discusses current knowledge on the formation of conidial and sclerotial pigments in aspergilli. It examines organization of genes involved in pigment production, biosynthetic pathways, and biological functions and reevaluates some of the current dogma, especially with respect to the DHN-melanin pathway, on the production of these enigmatic polymers. A better understanding of the structure and biosynthesis of melanins and other pigments could facilitate strategies to mitigate fungal pathogenesis.
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Affiliation(s)
- Perng-Kuang Chang
- Agricultural Research Service, U. S. Department of Agriculture, Southern Regional Research Center, 1100 Robert E. Lee Boulevard, New Orleans, LA, 70124, USA.
| | - Jeffrey W Cary
- Agricultural Research Service, U. S. Department of Agriculture, Southern Regional Research Center, 1100 Robert E. Lee Boulevard, New Orleans, LA, 70124, USA.
| | - Matthew D Lebar
- Agricultural Research Service, U. S. Department of Agriculture, Southern Regional Research Center, 1100 Robert E. Lee Boulevard, New Orleans, LA, 70124, USA
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