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Kushwah AS, Dixit H, Upadhyay V, Verma SK, Prasad R. The study of iron- and copper-binding proteome of Fusarium oxysporum and its effector candidates. Proteins 2024; 92:1097-1112. [PMID: 38666709 DOI: 10.1002/prot.26696] [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: 07/05/2023] [Revised: 03/26/2024] [Accepted: 04/08/2024] [Indexed: 08/07/2024]
Abstract
Fusarium oxysporum f.sp. lycopersici is a phytopathogen which causes vascular wilt disease in tomato plants. The survival tactics of both pathogens and hosts depend on intricate interactions between host plants and pathogenic microbes. Iron-binding proteins (IBPs) and copper-binding proteins (CBPs) play a crucial role in these interactions by participating in enzyme reactions, virulence, metabolism, and transport processes. We employed high-throughput computational tools at the sequence and structural levels to investigate the IBPs and CBPs of F. oxysporum. A total of 124 IBPs and 37 CBPs were identified in the proteome of Fusarium. The ranking of amino acids based on their affinity for binding with iron is Glu > His> Asp > Asn > Cys, and for copper is His > Asp > Cys respectively. The functional annotation, determination of subcellular localization, and Gene Ontology analysis of these putative IBPs and CBPs have unveiled their potential involvement in a diverse array of cellular and biological processes. Three iron-binding glycosyl hydrolase family proteins, along with four CBPs with carbohydrate-binding domains, have been identified as potential effector candidates. These proteins are distinct from the host Solanum lycopersicum proteome. Moreover, they are known to be located extracellularly and function as enzymes that degrade the host cell wall during pathogen-host interactions. The insights gained from this report on the role of metal ions in plant-pathogen interactions can help develop a better understanding of their fundamental biology and control vascular wilt disease in tomato plants.
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Affiliation(s)
- Ankita Singh Kushwah
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India
| | - Himisha Dixit
- Centre for Computational Biology & Bioinformatics, Central University of Himachal Pradesh, Kangra, Himachal Pradesh, India
| | - Vipin Upadhyay
- Centre for Computational Biology & Bioinformatics, Central University of Himachal Pradesh, Kangra, Himachal Pradesh, India
| | - Shailender Kumar Verma
- Centre for Computational Biology & Bioinformatics, Central University of Himachal Pradesh, Kangra, Himachal Pradesh, India
- Department of Environmental Studies, University of Delhi, North Campus, Delhi, India
| | - Ramasare Prasad
- Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India
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Moraes D, Tristão GB, Rappleye CA, Ray SC, Ribeiro-Dias F, Gomes RS, Assunção LDP, Paccez JD, Zancopé-Oliveira RM, Silva-Bailão MG, Soares CMDA, Bailão AM. The influence of a copper efflux pump in Histoplasma capsulatum virulence. FEBS J 2024; 291:744-760. [PMID: 37950580 DOI: 10.1111/febs.16999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 10/01/2023] [Accepted: 10/09/2023] [Indexed: 11/12/2023]
Abstract
During the infectious process, pathogenic microorganisms must obtain nutrients from the host in order to survive and proliferate. These nutritional sources include the metallic nutrient copper. Despite its essentiality, copper in large amounts is toxic. Host defense mechanisms use high copper poisoning as a fungicidal strategy to control infection. Transcriptional analyses showed that yeast cultured in the presence of copper or inside macrophages (24 h) had elevated expression of CRP1, a copper efflux pump, suggesting that Histoplasma capsulatum could be exposed to a high copper environment in macrophages during the innate immune stage of infection. Accordingly, macrophages cultured in high copper are more efficient in controlling H. capsulatum growth. Also, silencing of ATP7a, a copper pump that promotes the copper influx in phagosomes, increases fungal survival in macrophages. The rich copper environment faced by the fungus is not dependent on IFN-γ, since fungal CRP1 expression is induced in untreated macrophages. Appropriately, CRP1 knockdown fungal strains are more susceptible to macrophage control than wild-type yeasts. Additionally, CRP1 silencing decreases fungal burden in mice during the phase of innate immune response (4-day postinfection) and CRP1 is required for full virulence in a macrophage cell lines (J774 A.1 and RAW 264.7), as well as primary cells (BMDM). Thus, induction of fungal copper detoxifying genes during innate immunity and the attenuated virulence of CRP1-knockdown yeasts suggest that H. capsulatum is exposed to a copper-rich environment at early infection, but circumvents this condition to establish infection.
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Affiliation(s)
- Dayane Moraes
- Laboratório de Biologia Molecular (LBM), Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Gabriel Brum Tristão
- Laboratório de Biologia Molecular (LBM), Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Chad A Rappleye
- Department of Microbiology, Ohio State University, Columbus, OH, USA
| | - Stephanie C Ray
- Department of Microbiology, Ohio State University, Columbus, OH, USA
| | - Fátima Ribeiro-Dias
- Laboratório de Imunidade Natural (LIN), Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Brazil
| | - Rodrigo Saar Gomes
- Laboratório de Imunidade Natural (LIN), Instituto de Patologia Tropical e Saúde Pública, Universidade Federal de Goiás, Goiânia, Brazil
| | - Leandro do Prado Assunção
- Laboratório de Biologia Molecular (LBM), Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Juliano Domiraci Paccez
- Laboratório de Biologia Molecular (LBM), Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Rosely Maria Zancopé-Oliveira
- Laboratório de Micologia, Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Mirelle Garcia Silva-Bailão
- Laboratório de Biologia Molecular (LBM), Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Célia Maria de Almeida Soares
- Laboratório de Biologia Molecular (LBM), Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
| | - Alexandre Melo Bailão
- Laboratório de Biologia Molecular (LBM), Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Brazil
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Gunamalai L, Duanis-Assaf D, Sharir T, Maurer D, Feygenberg O, Sela N, Alkan N. Comparative Characterization of Virulent and Less-Virulent Lasiodiplodia theobromae Isolates. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2023; 36:502-515. [PMID: 37147768 DOI: 10.1094/mpmi-11-22-0234-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Lasiodiplodia theobromae attacks over 500 plant species and is an important pathogen of tropical and subtropical fruit. Due to global warming and climate change, the incidence of disease associated with L. theobromae is rising. Virulence tests performed on avocado and mango branches and fruit showed a large diversity of virulence of different L. theobromae isolates. Genome sequencing was performed for two L. theobromae isolates, representing more virulent (Avo62) and less-virulent (Man7) strains, to determine the cause of their variation. Comparative genomics, including orthologous and single-nucleotide polymorphism (SNP) analyses, identified SNPs in the less-virulent strain in genes related to secreted cell wall-degrading enzymes, stress, transporters, sucrose, and proline metabolism, genes in secondary metabolic clusters, effectors, genes involved in the cell cycle, and genes belonging to transcription factors that may contribute to the virulence of L. theobromae. Moreover, carbohydrate-active enzyme analysis revealed a minor increase in gene counts of cutinases and pectinases and the absence of a few glycoside hydrolases in the less-virulent isolate. Changes in gene-copy numbers might explain the morphological differences found in the in-vitro experiments. The more virulent Avo62 grew faster on glucose, sucrose, or starch as a single carbon source. It also grew faster under stress conditions, such as osmotic stress, alkaline pH, and relatively high temperature. Furthermore, the more virulent isolate secreted more ammonia than the less-virulent one both in vitro and in vivo. These study results describe genome-based variability related to L. theobromae virulence, which might prove useful for the mitigation of postharvest stem-end rot. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.
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Affiliation(s)
- Lavanya Gunamalai
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel
| | - Danielle Duanis-Assaf
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel
- Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Tom Sharir
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel
- Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel
| | - Dalia Maurer
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel
| | - Oleg Feygenberg
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel
| | - Noa Sela
- Department of Plant Pathology and Weed Research, ARO, Volcani Center, Rishon LeZion 7505101, Israel
| | - Noam Alkan
- Department of Postharvest Science of Fresh Produce, Agricultural Research Organization (ARO), Volcani Institute, Rishon LeZion 7505101, Israel
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Li J, Wang X, Zou J, Yang K, Wang X, Wang Y, Zhang H, Huang H, Su X, Yao B, Luo H, Qin X. Identification and Characterization of the Determinants of Copper Resistance in the Acidophilic Fungus Acidomyces richmondensis MEY-1 Using the CRISPR/Cas9 System. Appl Environ Microbiol 2023; 89:e0210722. [PMID: 36912653 PMCID: PMC10056952 DOI: 10.1128/aem.02107-22] [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: 12/23/2022] [Accepted: 02/14/2023] [Indexed: 03/14/2023] Open
Abstract
Copper (Cu) homeostasis has not been well documented in filamentous fungi, especially extremophiles. One of the main obstacles impeding their characterization is the lack of a powerful genome-editing tool. In this study, we applied a CRISPR/Cas9 system for efficient targeted gene disruption in the acidophilic fungus Acidomyces richmondensis MEY-1, formerly known as Bispora sp. strain MEY-1. Using this system, we investigated the basis of Cu tolerance in strain MEY-1. This strain has extremely high Cu tolerance among filamentous fungi, and the transcription factor ArAceA (A. richmondensis AceA) has been shown to be involved in this process. The ArAceA deletion mutant (ΔArAceA) exhibits specific growth defects at Cu concentrations of ≥10 mM and is transcriptionally more sensitive to Cu than the wild-type strain. In addition, the putative metallothionein ArCrdA was involved in Cu tolerance only under high Cu concentrations. MEY-1 has no Aspergillus nidulans CrpA homologs, which are targets of AceA-like transcription factors and play a role in Cu tolerance. Instead, we identified the Cu-transporting P-type ATPase ArYgA, homologous to A. nidulans YgA, which was involved in pigmentation rather than Cu tolerance. When the ΔArYgA mutant was grown on medium supplemented with Cu ions, the black color was completely restored. The lack of CrpA homologs in A. richmondensis MEY-1 and its high tolerance to Cu suggest that a novel Cu detoxification mechanism differing from the AceA-CrpA axis exists. IMPORTANCE Filamentous fungi are widely distributed worldwide and play an important ecological role as decomposers. However, the mechanisms of their adaptability to various environments are not fully understood. Various extremely acidophilic filamentous fungi have been isolated from acidic mine drainage (AMD) with extremely low pH and high heavy metal and sulfate concentrations, including A. richmondensis. The lack of genetic engineering tools, particularly genome-editing tools, hinders the study of these acidophilic and heavy metal-resistant fungi at the molecular level. Here, we first applied a CRISPR/Cas9-mediated gene-editing system to A. richmondensis MEY-1. Using this system, we identified and characterized the determinants of Cu resistance in A. richmondensis MEY-1. The conserved roles of the Cu-binding transcription factor ArAceA in Cu tolerance and the Cu-transporting P-type ATPase ArYgA in the Cu-dependent production of pigment were confirmed. Our findings provide insights into the molecular basis of Cu tolerance in the acidophilic fungus A. richmondensis MEY-1. Furthermore, the CRISPR/Cas9 system used here would be a powerful tool for studies of the mechanisms of adaptability of acidophilic fungi to extreme environments.
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Affiliation(s)
- Jinyang Li
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiao Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jiahuan Zou
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Kun Yang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaolu Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yuan Wang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Honglian Zhang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Huoqing Huang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaoyun Su
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Bin Yao
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Huiying Luo
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xing Qin
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
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Identification and Analysis of Fungal-Specific Regions in the Aspergillus fumigatus Cu Exporter CrpA That Are Essential for Cu Resistance but Not for Virulence. Int J Mol Sci 2023; 24:ijms24043705. [PMID: 36835119 PMCID: PMC9966986 DOI: 10.3390/ijms24043705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 02/17/2023] Open
Abstract
The opportunistic fungus Aspergillus fumigatus is the primary invasive mold pathogen in humans, and is responsible for an estimated 200,000 yearly deaths worldwide. Most fatalities occur in immunocompromised patients who lack the cellular and humoral defenses necessary to halt the pathogen's advance, primarily in the lungs. One of the cellular responses used by macrophages to counteract fungal infection is the accumulation of high phagolysosomal Cu levels to destroy ingested pathogens. A. fumigatus responds by activating high expression levels of crpA, which encodes a Cu+ P-type ATPase that actively transports excess Cu from the cytoplasm to the extracellular environment. In this study, we used a bioinformatics approach to identify two fungal-unique regions in CrpA that we studied by deletion/replacement, subcellular localization, Cu sensitivity in vitro, killing by mouse alveolar macrophages, and virulence in a mouse model of invasive pulmonary aspergillosis. Deletion of CrpA fungal-unique amino acids 1-211 containing two N-terminal Cu-binding sites, moderately increased Cu-sensitivity but did not affect expression or localization to the endoplasmic reticulum (ER) and cell surface. Replacement of CrpA fungal-unique amino acids 542-556 consisting of an intracellular loop between the second and third transmembrane helices resulted in ER retention of the protein and strongly increased Cu-sensitivity. Deleting CrpA N-terminal amino acids 1-211 or replacing amino acids 542-556 also increased sensitivity to killing by mouse alveolar macrophages. Surprisingly, the two mutations did not affect virulence in a mouse model of infection, suggesting that even weak Cu-efflux activity by mutated CrpA preserves fungal virulence.
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Chen Y, Cao Y, Gai Y, Ma H, Zhu Z, Chung KR, Li H. Genome-Wide Identification and Functional Characterization of GATA Transcription Factor Gene Family in Alternaria alternata. J Fungi (Basel) 2021; 7:jof7121013. [PMID: 34946995 PMCID: PMC8706292 DOI: 10.3390/jof7121013] [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: 10/15/2021] [Revised: 11/18/2021] [Accepted: 11/23/2021] [Indexed: 12/19/2022] Open
Abstract
In the present study, we identified six GATA transcription factors (AaAreA, AaAreB, AaLreA, AaLreB, AaNsdD, and AaSreA) and characterized their functions in response to environmental stress and virulence in the tangerine pathotype of Alternaria alternata. The targeted gene knockout of each of the GATA-coding genes decreased the growth to varying degrees. The mutation of AaAreA, AaAreB, AaLreB, or AaNsdD decreased the conidiation. All the GATA transcription factors were found to be required for tolerance to cumyl hydroperoxide and tert-butyl-hydroperoxide (oxidants) and Congo red (a cell-wall-destructing agent). Pathogenicity assays assessed on detached citrus leaves revealed that mutations of AaAreA, AaLreA, AaLreB, or AaNsdD significantly decreased the fungal virulence. A comparative transcriptome analysis between the ∆AreA mutant and the wild-type strain revealed that the inactivation of AaAreA led to alterations in the expression of genes involved in a number of biological processes, including oxidoreductase activity, amino acid metabolism, and secondary metabolite biogenesis. Taken together, our findings revealed that GATA-coding genes play diverse roles in response to environmental stress and are important regulators involved in fungal development, conidiation, ROS detoxification, as well as pathogenesis. This study, for the first time, systemically underlines the critical role of GATA transcription factors in response to environmental stress and virulence in A. alternata.
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Affiliation(s)
- Yanan Chen
- The Key Laboratory of Molecular Biology of Crop Pathogens and Insects of Ministry of Agriculture and Rural Affairs, The Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Y.C.); (Y.C.); (Y.G.); (H.M.); (Z.Z.)
| | - Yingzi Cao
- The Key Laboratory of Molecular Biology of Crop Pathogens and Insects of Ministry of Agriculture and Rural Affairs, The Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Y.C.); (Y.C.); (Y.G.); (H.M.); (Z.Z.)
| | - Yunpeng Gai
- The Key Laboratory of Molecular Biology of Crop Pathogens and Insects of Ministry of Agriculture and Rural Affairs, The Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Y.C.); (Y.C.); (Y.G.); (H.M.); (Z.Z.)
| | - Haijie Ma
- The Key Laboratory of Molecular Biology of Crop Pathogens and Insects of Ministry of Agriculture and Rural Affairs, The Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Y.C.); (Y.C.); (Y.G.); (H.M.); (Z.Z.)
- School of Agriculture and Food Sciences, Zhejiang Agriculture & Forestry University, Hangzhou 311300, China
| | - Zengrong Zhu
- The Key Laboratory of Molecular Biology of Crop Pathogens and Insects of Ministry of Agriculture and Rural Affairs, The Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Y.C.); (Y.C.); (Y.G.); (H.M.); (Z.Z.)
- Hainan Institute, Zhejiang University, Sanya 572000, China
| | - Kuang-Ren Chung
- Department of Plant Pathology, College of Agriculture and Natural Resources, National Chung-Hsing University, Taichung 40227, Taiwan;
| | - Hongye Li
- The Key Laboratory of Molecular Biology of Crop Pathogens and Insects of Ministry of Agriculture and Rural Affairs, The Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, China; (Y.C.); (Y.C.); (Y.G.); (H.M.); (Z.Z.)
- Correspondence: ; Tel.: +86-13634190823
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Sándor E, Kolláth IS, Fekete E, Bíró V, Flipphi M, Kovács B, Kubicek CP, Karaffa L. Carbon-Source Dependent Interplay of Copper and Manganese Ions Modulates the Morphology and Itaconic Acid Production in Aspergillus terreus. Front Microbiol 2021; 12:680420. [PMID: 34093503 PMCID: PMC8173074 DOI: 10.3389/fmicb.2021.680420] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 04/19/2021] [Indexed: 12/14/2022] Open
Abstract
The effects of the interplay of copper(II) and manganese(II) ions on growth, morphology and itaconic acid formation was investigated in a high-producing strain of Aspergillus terreus (NRRL1960), using carbon sources metabolized either mainly via glycolysis (D-glucose, D-fructose) or primarily via the pentose phosphate shunt (D-xylose, L-arabinose). Limiting Mn2+ concentration in the culture broth is indispensable to obtain high itaconic acid yields, while in the presence of higher Mn2+ concentrations yield decreases and biomass formation is favored. However, this low yield in the presence of high Mn2+ ion concentrations can be mitigated by increasing the Cu2+ concentration in the medium when D-glucose or D-fructose is the growth substrate, whereas this effect was at best modest during growth on D-xylose or L-arabinose. A. terreus displays a high tolerance to Cu2+ which decreased when Mn2+ availability became increasingly limiting. Under such conditions biomass formation on D-glucose or D-fructose could be sustained at concentrations up to 250 mg L–1 Cu2+, while on D-xylose- or L-arabinose biomass formation was completely inhibited at 100 mg L–1. High (>75%) specific molar itaconic acid yields always coincided with an “overflow-associated” morphology, characterized by small compact pellets (<250 μm diameter) and short chains of “yeast-like” cells that exhibit increased diameters relative to the elongated cells in growing filamentous hyphae. At low concentrations (≤1 mg L–1) of Cu2+ ions, manganese deficiency did not prevent filamentous growth. Mycelial- and cellular morphology progressively transformed into the typical overflow-associated one when external Cu2+ concentrations increased, irrespective of the available Mn2+. Our results indicate that copper ions are relevant for overflow metabolism and should be considered when optimizing itaconic acid fermentation in A. terreus.
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Affiliation(s)
- Erzsébet Sándor
- Institute of Food Science, Faculty of Agricultural and Food Science and Environmental Management, University of Debrecen, Debrecen, Hungary
| | - István S Kolláth
- Department of Biochemical Engineering, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary.,Doctoral School of Chemistry, University of Debrecen, Debrecen, Hungary
| | - Erzsébet Fekete
- Department of Biochemical Engineering, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary
| | - Vivien Bíró
- Department of Biochemical Engineering, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary.,Juhász-Nagy Pál Doctoral School of Biology and Environmental Sciences, University of Debrecen, Debrecen, Hungary
| | - Michel Flipphi
- Department of Biochemical Engineering, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary
| | - Béla Kovács
- Institute of Food Science, Faculty of Agricultural and Food Science and Environmental Management, University of Debrecen, Debrecen, Hungary
| | - Christian P Kubicek
- Institute of Chemical, Environmental & Bioscience Engineering, TU Wien, Vienna, Austria
| | - Levente Karaffa
- Department of Biochemical Engineering, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary
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