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Westrick NM, Park SC, Keller NP, Smith DL, Kabbage M. A broadly conserved fungal alcohol oxidase (AOX) facilitates fungal invasion of plants. MOLECULAR PLANT PATHOLOGY 2023; 24:28-43. [PMID: 36251755 PMCID: PMC9742500 DOI: 10.1111/mpp.13274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/13/2022] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
Alcohol oxidases (AOXs) are ecologically important enzymes that facilitate a number of plant-fungal interactions. Within Ascomycota they are primarily associated with methylotrophy, as a peroxisomal AOX catalysing the conversion of methanol to formaldehyde in methylotrophic yeast. In this study we demonstrate that AOX orthologues are phylogenetically conserved proteins that are common in the genomes of nonmethylotrophic, plant-associating fungi. Additionally, AOX orthologues are highly expressed during infection in a range of diverse pathosystems. To study the role of AOX in plant colonization, AOX knockout mutants were generated in the broad host range pathogen Sclerotinia sclerotiorum. Disease assays in soybean showed that these mutants had a significant virulence defect as evidenced by markedly reduced stem lesions and mortality rates. Chemical genomics suggested that SsAOX may function as an aromatic AOX, and growth assays demonstrated that ΔSsAOX is incapable of properly utilizing plant extract as a nutrient source. Profiling of known aromatic alcohols pointed towards the monolignol coniferyl alcohol (CA) as a possible substrate for SsAOX. As CA and other monolignols are ubiquitous among land plants, the presence of highly conserved AOX orthologues throughout Ascomycota implies that this is a broadly conserved protein used by ascomycete fungi during plant colonization.
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Affiliation(s)
- Nathaniel M. Westrick
- Department of Plant PathologyUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
- United States Department of Agriculture–Agricultural Research ServiceMadisonWisconsinUSA
| | - Sung Chul Park
- Department of Medical Microbiology and ImmunologyUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Nancy P. Keller
- Department of Plant PathologyUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
- Department of Medical Microbiology and ImmunologyUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Damon L. Smith
- Department of Plant PathologyUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Mehdi Kabbage
- Department of Plant PathologyUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
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2
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Nigg M, de Oliveira TC, Sarmiento-Villamil JL, de la Bastide PY, Hintz WE, Sherif SM, Shukla M, Bernier L, Saxena PK. Comparative Analysis of Transcriptomes of Ophiostoma novo-ulmi ssp. americana Colonizing Resistant or Sensitive Genotypes of American Elm. J Fungi (Basel) 2022; 8:637. [PMID: 35736120 PMCID: PMC9224576 DOI: 10.3390/jof8060637] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 05/26/2022] [Accepted: 06/11/2022] [Indexed: 12/10/2022] Open
Abstract
The Ascomycete Ophiostoma novo-ulmi threatens elm populations worldwide. The molecular mechanisms underlying its pathogenicity and virulence are still largely uncharacterized. As part of a collaborative study of the O. novo-ulmi-elm interactome, we analyzed the O. novo-ulmi ssp. americana transcriptomes obtained by deep sequencing of messenger RNAs recovered from Ulmus americana saplings from one resistant (Valley Forge, VF) and one susceptible (S) elm genotypes at 0 and 96 h post-inoculation (hpi). Transcripts were identified for 6424 of the 8640 protein-coding genes annotated in the O. novo-ulmi nuclear genome. A total of 1439 genes expressed in planta had orthologs in the PHI-base curated database of genes involved in host-pathogen interactions, whereas 472 genes were considered differentially expressed (DEG) in S elms (370 genes) and VF elms (102 genes) at 96 hpi. Gene ontology (GO) terms for processes and activities associated with transport and transmembrane transport accounted for half (27/55) of GO terms that were significantly enriched in fungal genes upregulated in S elms, whereas the 22 GO terms enriched in genes overexpressed in VF elms included nine GO terms associated with metabolism, catabolism and transport of carbohydrates. Weighted gene co-expression network analysis identified three modules that were significantly associated with higher gene expression in S elms. The three modules accounted for 727 genes expressed in planta and included 103 DEGs upregulated in S elms. Knockdown- and knockout mutants were obtained for eight O. novo-ulmi genes. Although mutants remained virulent towards U. americana saplings, we identified a large repertoire of additional candidate O. novo-ulmi pathogenicity genes for functional validation by loss-of-function approaches.
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Affiliation(s)
- Martha Nigg
- Centre d’Étude de la Forêt (CEF) and Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6, Canada; (M.N.); (T.C.d.O.); (J.L.S.-V.)
| | - Thais C. de Oliveira
- Centre d’Étude de la Forêt (CEF) and Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6, Canada; (M.N.); (T.C.d.O.); (J.L.S.-V.)
| | - Jorge L. Sarmiento-Villamil
- Centre d’Étude de la Forêt (CEF) and Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6, Canada; (M.N.); (T.C.d.O.); (J.L.S.-V.)
| | - Paul Y. de la Bastide
- Department of Biology, Centre for Forest Biology, University of Victoria, Victoria, BC V8W 2Y2, Canada; (P.Y.d.l.B.); (W.E.H.)
| | - Will E. Hintz
- Department of Biology, Centre for Forest Biology, University of Victoria, Victoria, BC V8W 2Y2, Canada; (P.Y.d.l.B.); (W.E.H.)
| | - Sherif M. Sherif
- Alson H. Smith Jr. Agricultural Research and Extension Center, School of Plant and Environmental Sciences, Virginia Tech, Winchester, VA 22602, USA;
| | - Mukund Shukla
- Department of Plant Agriculture, Gosling Research Institute for Plant Preservation (GRIPP), University of Guelph, Guelph, ON N1G 2W1, Canada;
| | - Louis Bernier
- Centre d’Étude de la Forêt (CEF) and Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC G1V 0A6, Canada; (M.N.); (T.C.d.O.); (J.L.S.-V.)
| | - Praveen K. Saxena
- Department of Plant Agriculture, Gosling Research Institute for Plant Preservation (GRIPP), University of Guelph, Guelph, ON N1G 2W1, Canada;
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3
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Mwape VW, Mobegi FM, Regmi R, Newman TE, Kamphuis LG, Derbyshire MC. Analysis of differentially expressed Sclerotinia sclerotiorum genes during the interaction with moderately resistant and highly susceptible chickpea lines. BMC Genomics 2021; 22:333. [PMID: 33964897 PMCID: PMC8106195 DOI: 10.1186/s12864-021-07655-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 04/27/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Sclerotinia sclerotiorum, the cause of Sclerotinia stem rot (SSR), is a host generalist necrotrophic fungus that can cause major yield losses in chickpea (Cicer arietinum) production. This study used RNA sequencing to conduct a time course transcriptional analysis of S. sclerotiorum gene expression during chickpea infection. It explores pathogenicity and developmental factors employed by S. sclerotiorum during interaction with chickpea. RESULTS During infection of moderately resistant (PBA HatTrick) and highly susceptible chickpea (Kyabra) lines, 9491 and 10,487 S. sclerotiorum genes, respectively, were significantly differentially expressed relative to in vitro. Analysis of the upregulated genes revealed enrichment of Gene Ontology biological processes, such as oxidation-reduction process, metabolic process, carbohydrate metabolic process, response to stimulus, and signal transduction. Several gene functional categories were upregulated in planta, including carbohydrate-active enzymes, secondary metabolite biosynthesis clusters, transcription factors and candidate secreted effectors. Differences in expression of four S. sclerotiorum genes on varieties with different levels of susceptibility were also observed. CONCLUSION These findings provide a framework for a better understanding of S. sclerotiorum interactions with hosts of varying susceptibility levels. Here, we report for the first time on the S. sclerotiorum transcriptome during chickpea infection, which could be important for further studies on this pathogen's molecular biology.
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Affiliation(s)
- Virginia W Mwape
- Centre for Crop and Disease Management, Curtin University, Bentley, WA, 6102, Australia. .,Commonwealth Scientific and Industrial Research Organization, Agriculture and Food, Floreat, WA, Australia.
| | - Fredrick M Mobegi
- Centre for Crop and Disease Management, Curtin University, Bentley, WA, 6102, Australia
| | - Roshan Regmi
- Centre for Crop and Disease Management, Curtin University, Bentley, WA, 6102, Australia.,Commonwealth Scientific and Industrial Research Organization, Agriculture and Food, Floreat, WA, Australia
| | - Toby E Newman
- Centre for Crop and Disease Management, Curtin University, Bentley, WA, 6102, Australia
| | - Lars G Kamphuis
- Centre for Crop and Disease Management, Curtin University, Bentley, WA, 6102, Australia. .,Commonwealth Scientific and Industrial Research Organization, Agriculture and Food, Floreat, WA, Australia.
| | - Mark C Derbyshire
- Centre for Crop and Disease Management, Curtin University, Bentley, WA, 6102, Australia
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Pérez-Torres CA, Ibarra-Laclette E, Hernández-Domínguez EE, Rodríguez-Haas B, Pérez-Lira AJ, Villafán E, Alonso-Sánchez A, García-Ávila CDJ, Ramírez-Pool JA, Sánchez-Rangel D. Molecular evidence of the avocado defense response to Fusarium kuroshium infection: a deep transcriptome analysis using RNA-Seq. PeerJ 2021; 9:e11215. [PMID: 33954045 PMCID: PMC8052963 DOI: 10.7717/peerj.11215] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 03/15/2021] [Indexed: 01/13/2023] Open
Abstract
Fusarium kuroshium is a novel member of the Ambrosia Fusarium Clade (AFC) that has been recognized as one of the symbionts of the invasive Kuroshio shot hole borer, an Asian ambrosia beetle. This complex is considered the causal agent of Fusarium dieback, a disease that has severely threatened natural forests, landscape trees, and avocado orchards in the last 8 years. Despite the interest in this species, the molecular responses of both the host and F. kuroshium during the infection process and disease establishment remain unknown. In this work, we established an in vitro pathosystem using Hass avocado stems inoculated with F. kuroshium to investigate differential gene expression at 1, 4, 7 and 14 days post-inoculation. RNA-seq technology allowed us to obtain data from both the plant and the fungus, and the sequences obtained from both organisms were analyzed independently. The pathosystem established was able to mimic Fusarium dieback symptoms, such as carbohydrate exudation, necrosis, and vascular tissue discoloration. The results provide interesting evidence regarding the genes that may play roles in the avocado defense response to Fusarium dieback disease. The avocado data set comprised a coding sequence collection of 51,379 UniGenes, from which 2,403 (4.67%) were identified as differentially expressed. The global expression analysis showed that F. kuroshium responsive UniGenes can be clustered into six groups according to their expression profiles. The biologically relevant functional categories that were identified included photosynthesis as well as responses to stress, hormones, abscisic acid, and water deprivation. Additionally, processes such as oxidation-reduction, organization and biogenesis of the cell wall and polysaccharide metabolism were detected. Moreover, we identified orthologues of nucleotide-binding leucine-rich receptors, and their possible action mode was analyzed. In F. kuroshium, we identified 57 differentially expressed genes. Interestingly, the alcohol metabolic process biological category had the highest number of upregulated genes, and the enzyme group in this category may play an important role in the mechanisms of secondary metabolite detoxification. Hydrolytic enzymes, such as endoglucanases and a pectate lyase, were also identified, as well as some proteases. In conclusion, our research was conducted mainly to explain how the vascular tissue of a recognized host of the ambrosia complex responds during F. kuroshium infection since Fusarium dieback is an ambrosia beetle-vectored disease and many variables facilitate its establishment.
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Affiliation(s)
- Claudia-Anahí Pérez-Torres
- Catedrático CONACyT en la Red de Estudios Moleculares Avanzados, Instituto de Ecología A.C., Xalapa, Veracruz, México
| | | | | | | | - Alan-Josué Pérez-Lira
- Red de Estudios Moleculares Avanzados, Instituto de Ecología A.C., Xalapa, Veracruz, México
| | - Emanuel Villafán
- Red de Estudios Moleculares Avanzados, Instituto de Ecología A.C., Xalapa, Veracruz, México
| | | | - Clemente de Jesús García-Ávila
- Centro Nacional de Referencia Fitosanitaria, Servicio Nacional de Sanidad, Inocuidad y Calidad Agroalimentaria, Tecámac, Estado de México, México
| | - José-Abrahán Ramírez-Pool
- Centro Nacional de Referencia Fitosanitaria, Servicio Nacional de Sanidad, Inocuidad y Calidad Agroalimentaria, Tecámac, Estado de México, México.,Departamento de Biotecnología y Bioingeniería, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de México, México
| | - Diana Sánchez-Rangel
- Catedrático CONACyT en la Red de Estudios Moleculares Avanzados, Instituto de Ecología A.C., Xalapa, Veracruz, México
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5
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Chen D, Li G, Liu J, Wisniewski M, Droby S, Levin E, Huang S, Liu Y. Multiple transcriptomic analyses and characterization of pathogen-related core effectors and LysM family members reveal their differential roles in fungal growth and pathogenicity in Penicillium expansum. Mol Genet Genomics 2020; 295:1415-1429. [PMID: 32656702 DOI: 10.1007/s00438-020-01710-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 07/03/2020] [Indexed: 02/07/2023]
Abstract
Penicillium expansum is a destructive phytopathogen causing postharvest decay on many stored fruits. To develop effective and safe management strategies, it is important to investigate its pathogenicity-related mechanisms. In this study, a bioinformatic pipeline was constructed and 50 core effector genes were identified in P. expansum using multiple RNA-seq data sets and their putative functions were implicated by comparatively homologous analyses using pathogen-host interaction database. To functionally characterize P. expansum LysM domain proteins during infection, null mutants for the 15 uncharacterized putative LysM effectors were constructed and the fungal growth rate on either PDA or Cazpek medium or lesion expansion rate on the infected apple fruits was evaluated. The results showed the growth rate of knockout mutants from PeLysM5, PeLysM12 and PeLysM15 was retarded on PDA medium. No significant difference in growth rate was observed between wild type and all mutants on solid Cazpek medium. Nevertheless, the hypha of wild type displayed deeper yellow on the back of Cazpek medium than those of knockout mutants. On the infecting apples fruits, the knockout mutants from PeLysM5, PeLysM7, PeLysM8, PeLysM9, PeLysM10, PeLysM11, PeLysM14, PeLysM15, PeLysM16, PeLysM18 and PeLysM19 showed enhanced fungal virulence, with faster decaying on infected fruits than those from wild type. By contrast, the knockout mutation at PeLysM12 locus led to reduced lesion expansion rate on the infected apple fruits. In addition, P. expansum-apple interaction RNA-seq experiment was performed using apple fruit tissues infected by the wild type and knockout mutant ΔPeLysM15, respectively. Transcriptome analyses indicated that deletion of PeLysM15 could activate expression of several core effector genes, such as PEX2_055830, PEX2_036960 and PEX2_108150, and a chitin-binding protein, PEX2_064520. These results suggest PeLysM15 may play pivotal roles in fungal growth and development and involve pathogen-host interaction by modulating other effector genes' expression. Our results could provide solid data reference and good candidates for further pathogen-related studies in P. expansum.
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Affiliation(s)
- Danyang Chen
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Guangwei Li
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Jia Liu
- Chongqing Key Laboratory of Economic Plant Biotechnology, Collaborative Innovation Centre of Special Plant Industry in Chongqing, College of Forestry and Life Science, Institute of Special Plants, Chongqing University of Arts and Sciences, Yongchuan, 402160, China
| | - Michael Wisniewski
- United States Department of Agriculture-Agricultural Research Service, Kearneysville, WV, USA
| | - Samir Droby
- Agricultural Research Organization, Volcani Center, Bet Dagan, Israel
| | - Elena Levin
- Agricultural Research Organization, Volcani Center, Bet Dagan, Israel
| | - Shengxiong Huang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China.
| | - Yongsheng Liu
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, 230009, China.
- School of Horticulture, Anhui Agricultural University, Hefei, 230036, China.
- Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China.
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6
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Sützl L, Foley G, Gillam EMJ, Bodén M, Haltrich D. The GMC superfamily of oxidoreductases revisited: analysis and evolution of fungal GMC oxidoreductases. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:118. [PMID: 31168323 PMCID: PMC6509819 DOI: 10.1186/s13068-019-1457-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 05/02/2019] [Indexed: 05/03/2023]
Abstract
BACKGROUND The glucose-methanol-choline (GMC) superfamily is a large and functionally diverse family of oxidoreductases that share a common structural fold. Fungal members of this superfamily that are characterised and relevant for lignocellulose degradation include aryl-alcohol oxidoreductase, alcohol oxidase, cellobiose dehydrogenase, glucose oxidase, glucose dehydrogenase, pyranose dehydrogenase, and pyranose oxidase, which together form family AA3 of the auxiliary activities in the CAZy database of carbohydrate-active enzymes. Overall, little is known about the extant sequence space of these GMC oxidoreductases and their phylogenetic relations. Although some individual forms are well characterised, it is still unclear how they compare in respect of the complete enzyme class and, therefore, also how generalizable are their characteristics. RESULTS To improve the understanding of the GMC superfamily as a whole, we used sequence similarity networks to cluster large numbers of fungal GMC sequences and annotate them according to functionality. Subsequently, different members of the GMC superfamily were analysed in detail with regard to their sequences and phylogeny. This allowed us to define the currently characterised sequence space and show that complete clades of some enzymes have not been studied in any detail to date. Finally, we interpret our results from an evolutionary perspective, where we could show, for example, that pyranose dehydrogenase evolved from aryl-alcohol oxidoreductase after a change in substrate specificity and that the cytochrome domain of cellobiose dehydrogenase was regularly lost during evolution. CONCLUSIONS This study offers new insights into the sequence variation and phylogenetic relationships of fungal GMC/AA3 sequences. Certain clades of these GMC enzymes identified in our phylogenetic analyses are completely uncharacterised to date, and might include enzyme activities of varying specificities and/or activities that are hitherto unstudied.
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Affiliation(s)
- Leander Sützl
- Food Biotechnology Laboratory, Department of Food Science and Technology, BOKU-University of Natural Resources and Life Sciences Vienna, Vienna, Austria
- Doctoral Programme BioToP-Biomolecular Technology of Proteins, BOKU-University of Natural Resources and Life Sciences Vienna, Vienna, Austria
| | - Gabriel Foley
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, Australia
| | - Elizabeth M J Gillam
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, Australia
| | - Mikael Bodén
- School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, Australia
| | - Dietmar Haltrich
- Food Biotechnology Laboratory, Department of Food Science and Technology, BOKU-University of Natural Resources and Life Sciences Vienna, Vienna, Austria
- Doctoral Programme BioToP-Biomolecular Technology of Proteins, BOKU-University of Natural Resources and Life Sciences Vienna, Vienna, Austria
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7
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Ghosh S, Kanwar P, Jha G. Identification of candidate pathogenicity determinants of Rhizoctonia solani AG1-IA, which causes sheath blight disease in rice. Curr Genet 2017; 64:729-740. [PMID: 29196814 DOI: 10.1007/s00294-017-0791-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 11/24/2017] [Accepted: 11/27/2017] [Indexed: 01/04/2023]
Abstract
Sheath blight disease is one of the predominant diseases of rice and it is caused by the necrotrophic fungal pathogen Rhizoctonia solani. The mechanistic insight about its widespread success as a broad host range pathogen is limited. In this study, we endeavor to identify pathogenicity determinants of R. solani during infection process in rice. Through RNAseq analysis, we identified a total of 65 and 232 R. solani (strain BRS1) genes to be commonly upregulated in three different rice genotypes (PB1, Tetep, and TP309) at establishment and necrotrophic phase, respectively. The induction of genes encoding extracellular protease, ABC transporter, and transcription factors were notable during establishment phase. While during necrotrophic phase, several CAZymes, sugar transporters, cellular metabolism, and protein degradation-related genes were prominently induced. We have also identified few putative secreted effector encoding genes that were upregulated during pathogenesis. The qPCR analysis further validated the phase-specific expression dynamics of some selected putative effectors and pathogenicity-associated genes. Overall, the present study reports identification of key genes and processes that might be crucial for R. solani pathogenesis. The ability to effectively damage host cell wall and survive in hostile plant environment by managing oxidative stress, cytotoxic compounds, etc. is being proposed to be important for pathogenesis of R. solani in rice. The functional characterization of these genes would provide key insights about this important pathosystem and facilitate development of strategies to control this devastating disease.
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Affiliation(s)
- Srayan Ghosh
- Plant Microbe Interactions Laboratory, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Poonam Kanwar
- Plant Microbe Interactions Laboratory, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India
| | - Gopaljee Jha
- Plant Microbe Interactions Laboratory, National Institute of Plant Genome Research, Aruna Asaf Ali Marg, New Delhi, 110067, India.
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8
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Bradshaw RE, Guo Y, Sim AD, Kabir MS, Chettri P, Ozturk IK, Hunziker L, Ganley RJ, Cox MP. Genome-wide gene expression dynamics of the fungal pathogen Dothistroma septosporum throughout its infection cycle of the gymnosperm host Pinus radiata. MOLECULAR PLANT PATHOLOGY 2016; 17:210-24. [PMID: 25919703 PMCID: PMC4746707 DOI: 10.1111/mpp.12273] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
We present genome-wide gene expression patterns as a time series through the infection cycle of the fungal pine needle blight pathogen, Dothistroma septosporum, as it invades its gymnosperm host, Pinus radiata. We determined the molecular changes at three stages of the disease cycle: epiphytic/biotrophic (early), initial necrosis (mid) and mature sporulating lesion (late). Over 1.7 billion combined plant and fungal reads were sequenced to obtain 3.2 million fungal-specific reads, which comprised as little as 0.1% of the sample reads early in infection. This enriched dataset shows that the initial biotrophic stage is characterized by the up-regulation of genes encoding fungal cell wall-modifying enzymes and signalling proteins. Later necrotrophic stages show the up-regulation of genes for secondary metabolism, putative effectors, oxidoreductases, transporters and starch degradation. This in-depth through-time transcriptomic study provides our first snapshot of the gene expression dynamics that characterize infection by this fungal pathogen in its gymnosperm host.
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Affiliation(s)
- Rosie E Bradshaw
- Bio-Protection Research Centre, Institute of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
| | - Yanan Guo
- Bio-Protection Research Centre, Institute of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
| | - Andre D Sim
- Bio-Protection Research Centre, Institute of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
| | - M Shahjahan Kabir
- Bio-Protection Research Centre, Institute of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
| | - Pranav Chettri
- Bio-Protection Research Centre, Institute of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
| | - Ibrahim K Ozturk
- Bio-Protection Research Centre, Institute of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
| | - Lukas Hunziker
- Bio-Protection Research Centre, Institute of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
| | - Rebecca J Ganley
- Scion, NZ Forest Research Institute Ltd, Rotorua, 3010, New Zealand
| | - Murray P Cox
- Bio-Protection Research Centre, Institute of Fundamental Sciences, Massey University, Palmerston North, 4474, New Zealand
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10
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He R, Salvato F, Park JJ, Kim MJ, Nelson W, Balbuena TS, Willer M, Crow JA, May GD, Soderlund CA, Thelen JJ, Gang DR. A systems-wide comparison of red rice (Oryza longistaminata) tissues identifies rhizome specific genes and proteins that are targets for cultivated rice improvement. BMC PLANT BIOLOGY 2014; 14:46. [PMID: 24521476 PMCID: PMC3933257 DOI: 10.1186/1471-2229-14-46] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Accepted: 02/07/2014] [Indexed: 05/04/2023]
Abstract
BACKGROUND The rhizome, the original stem of land plants, enables species to invade new territory and is a critical component of perenniality, especially in grasses. Red rice (Oryza longistaminata) is a perennial wild rice species with many valuable traits that could be used to improve cultivated rice cultivars, including rhizomatousness, disease resistance and drought tolerance. Despite these features, little is known about the molecular mechanisms that contribute to rhizome growth, development and function in this plant. RESULTS We used an integrated approach to compare the transcriptome, proteome and metabolome of the rhizome to other tissues of red rice. 116 Gb of transcriptome sequence was obtained from various tissues and used to identify rhizome-specific and preferentially expressed genes, including transcription factors and hormone metabolism and stress response-related genes. Proteomics and metabolomics approaches identified 41 proteins and more than 100 primary metabolites and plant hormones with rhizome preferential accumulation. Of particular interest was the identification of a large number of gene transcripts from Magnaportha oryzae, the fungus that causes rice blast disease in cultivated rice, even though the red rice plants showed no sign of disease. CONCLUSIONS A significant set of genes, proteins and metabolites appear to be specifically or preferentially expressed in the rhizome of O. longistaminata. The presence of M. oryzae gene transcripts at a high level in apparently healthy plants suggests that red rice is resistant to this pathogen, and may be able to provide genes to cultivated rice that will enable resistance to rice blast disease.
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Affiliation(s)
- Ruifeng He
- Institute of Biological Chemistry, Washington State University, PO Box 646340, Pullman, WA 99164, USA
| | - Fernanda Salvato
- Department of Biochemistry and Interdisciplinary Plant Group, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA
- Current Address: Departamento de Tecnologia, Universidade Estadual Paulista, Jaboticabal, SP 14884-900, Brazil
| | - Jeong-Jin Park
- Institute of Biological Chemistry, Washington State University, PO Box 646340, Pullman, WA 99164, USA
| | - Min-Jeong Kim
- Institute of Biological Chemistry, Washington State University, PO Box 646340, Pullman, WA 99164, USA
| | - William Nelson
- BIO5 Institute, The University of Arizona, Tucson, AZ 85721, USA
| | - Tiago S Balbuena
- Department of Biochemistry and Interdisciplinary Plant Group, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA
- Current Address: Departamento de Tecnologia, Universidade Estadual Paulista, Jaboticabal, SP 14884-900, Brazil
| | - Mark Willer
- BIO5 Institute, The University of Arizona, Tucson, AZ 85721, USA
| | - John A Crow
- National Center for Genome Resources, Santa Fe, NM 87505, USA
| | - Greg D May
- National Center for Genome Resources, Santa Fe, NM 87505, USA
| | | | - Jay J Thelen
- Department of Biochemistry and Interdisciplinary Plant Group, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, MO 65211, USA
| | - David R Gang
- Institute of Biological Chemistry, Washington State University, PO Box 646340, Pullman, WA 99164, USA
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An overview on alcohol oxidases and their potential applications. Appl Microbiol Biotechnol 2013; 97:4259-75. [DOI: 10.1007/s00253-013-4842-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 03/06/2013] [Accepted: 03/07/2013] [Indexed: 10/27/2022]
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de Oliveira BV, Teixeira GS, Reis O, Barau JG, Teixeira PJPL, do Rio MCS, Domingues RR, Meinhardt LW, Paes Leme AF, Rincones J, Pereira GAG. A potential role for an extracellular methanol oxidase secreted by Moniliophthora perniciosa in Witches' broom disease in cacao. Fungal Genet Biol 2012; 49:922-32. [PMID: 23022488 DOI: 10.1016/j.fgb.2012.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Revised: 08/28/2012] [Accepted: 09/02/2012] [Indexed: 11/29/2022]
Abstract
The hemibiotrophic basidiomycete fungus Moniliophthora perniciosa, the causal agent of Witches' broom disease (WBD) in cacao, is able to grow on methanol as the sole carbon source. In plants, one of the main sources of methanol is the pectin present in the structure of cell walls. Pectin is composed of highly methylesterified chains of galacturonic acid. The hydrolysis between the methyl radicals and galacturonic acid in esterified pectin, mediated by a pectin methylesterase (PME), releases methanol, which may be decomposed by a methanol oxidase (MOX). The analysis of the M. pernciosa genome revealed putative mox and pme genes. Real-time quantitative RT-PCR performed with RNA from mycelia grown in the presence of methanol or pectin as the sole carbon source and with RNA from infected cacao seedlings in different stages of the progression of WBD indicate that the two genes are coregulated, suggesting that the fungus may be metabolizing the methanol released from pectin. Moreover, immunolocalization of homogalacturonan, the main pectic domain that constitutes the primary cell wall matrix, shows a reduction in the level of pectin methyl esterification in infected cacao seedlings. Although MOX has been classically classified as a peroxisomal enzyme, M. perniciosa presents an extracellular methanol oxidase. Its activity was detected in the fungus culture supernatants, and mass spectrometry analysis indicated the presence of this enzyme in the fungus secretome. Because M. pernciosa possesses all genes classically related to methanol metabolism, we propose a peroxisome-independent model for the utilization of methanol by this fungus, which begins with the extracellular oxidation of methanol derived from the demethylation of pectin and finishes in the cytosol.
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Affiliation(s)
- Bruno V de Oliveira
- Laboratório de Genômica e Expressão, Departamento de Genética, Evolução e Bioagentes, Instituto de Biologia, Universidade Estadual de Campinas, CP 6109, 13083-970 Campinas, SP, Brazil
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Isobe K, Kataoka M, Ogawa J, Hasegawa J, Shimizu S. Microbial oxidases catalyzing conversion of glycolaldehyde into glyoxal. N Biotechnol 2011; 29:177-82. [PMID: 21820089 DOI: 10.1016/j.nbt.2011.05.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 04/26/2011] [Accepted: 05/10/2011] [Indexed: 10/18/2022]
Abstract
The present paper reviews oxidases catalyzing conversion of glycolaldehyde into glyoxal. The enzymatic oxidation of glycolaldehyde into glyoxal was first reported in alcohol oxidases (AODs) from methylotrophic yeasts such as Candida and Pichia, and glycerol oxidase (GLOD) from Aspergillus japonicus, although it had been reported that these enzymes are specific to short-chain linear aliphatic alcohols and glycerol, respectively. These enzymes continuously oxidized ethylene glycol into glyoxal via glycolaldehyde. The AODs produced by Aspergillus ochraceus and Penicillium purpurescens also oxidized glycolaldehyde. A new enzyme exhibiting oxidase activity for glycolaldehyde was reported from a newly isolated bacterium, Paenibacillus sp. AIU 311. The Paenibacillus enzyme exhibited high activity for aldehyde alcohols such as glycolaldehyde and glyceraldehyde, but not for methanol, ethanol, ethylene glycol or glycerol. The deduced amino acid sequence of the Paenibacillus AOD was similar to that of superoxide dismutases (SODs), but not to that of methylotrophic yeast AODs. Then, it was demonstrated that SODs had oxidase activity for aldehyde alcohols including glycolaldehyde. The present paper describes characteristics of glycolaldehyde oxidation by those enzymes produced by different microorganisms.
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Affiliation(s)
- Kimiyasu Isobe
- Department of Biological Chemistry and Food Science, Iwate University, Ueda-3, Morioka 020-8550, Japan.
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Leal GA, Gomes LH, Albuquerque PSB, Tavares FCA, Figueira A. Searching for Moniliophthora perniciosa pathogenicity genes. Fungal Biol 2010; 114:842-54. [PMID: 20943194 DOI: 10.1016/j.funbio.2010.07.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Revised: 07/21/2010] [Accepted: 07/30/2010] [Indexed: 10/19/2022]
Abstract
The basidiomycete Moniliophthora perniciosa is the causal agent of witches' broom disease of Theobroma cacao (cacao). Pathogenesis mechanisms of this hemibiotrophic fungus are largely unknown. An approach to identify putative pathogenicity genes is searching for sequences induced in mycelia grown under in vitro conditions. Using this approach, genes from M. perniciosa induced under limiting nitrogen and light were identified from a cDNA library enriched by suppression subtractive hybridization as potential putative pathogenicity genes. From the 159 identified unique sequences, 59 were annotated and classified by gene ontology. Two sequences were categorized as "Defence genes, Virulence, and Cell response" presumably coding for allergenic proteins, whose homologues from other fungi are inducers of animal or plant defences. Differential gene expression was evaluated by quantitative amplification of reversed transcripts (RT-qPCR) of the putative identified genes coding for the two allergenic proteins (Aspf13 and 88KD), and for the enzymes Arylsulfatase (AS); Aryl-Alcohol Oxidase; Aldo-Keto Reductase (AK); Cytochrome P450 (P450); Phenylalanine Ammonia-Lyase; and Peroxidase from mycelia grown under contrasting N concentrations. All genes were validated for differential expression, except for the putative Peroxidase. The same eight genes were analysed for expression in susceptible plants inoculated with M. perniciosa, and six were induced during the early asymptomatic stage of the disease. In infected host tissues, transcripts of 88KD and AS were found more abundant at the biotrophic phase, while those from Aspf13, AK, PAL, and P450 accumulated at the necrotrophic phase, enabling to suggest that mycelia transition from biotrophic to necrotrophic might occur earlier than currently considered. These sequences appeared to be virulence life-style genes, which encode factors or enzymes that enable invasion, colonization or intracellular survival, or manipulate host factors to benefit the pathogen's own survival in the hostile environment.
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Affiliation(s)
- Gildemberg A Leal
- Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Piracicaba, SP, Brazil
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15
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You BJ, Lee MH, Chung KR. Gene-specific disruption in the filamentous fungus Cercospora nicotianae using a split-marker approach. Arch Microbiol 2009; 191:615-22. [PMID: 19506835 DOI: 10.1007/s00203-009-0489-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 04/22/2009] [Accepted: 05/25/2009] [Indexed: 12/24/2022]
Abstract
To determine if DNA configuration, gene locus, and flanking sequences will affect homologous recombination in the phytopathogenic fungus Cercospora nicotianae, we evaluated and compared disruption efficiency targeting four cercosporin toxin biosynthetic genes encoding a polyketide synthase (CTB1), a monooxygenase/O-methyltransferase (CTB3), a NADPH-dependent oxidoreductase (CTB5), and a FAD/FMN-dependent oxidoreductase (CTB7). Transformation of C. nicotianae using a circular plasmid resulted in low disruption frequency. The use of endonucleases or a selectable marker DNA fragment flanked by homologous sequence either at one end or at both ends in the transformation procedures, increased disruption efficiency in some but not all CTB genes. A split-marker approach, using two DNA fragments overlapping within the selectable marker, increased the frequency of targeted gene disruption and homologous integration as high as 50%, depending on the target gene and on the length of homologous DNA sequence flanking the selectable marker. The results indicate that the split-marker approach favorably decreased ectopic integration and thus, greatly facilitated targeted gene disruption in this important fungal pathogen.
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Affiliation(s)
- Bang-Jau You
- School of Chinese Medicine Resources, College of Pharmacy, China Medical University, 91 Hsueh-Shih Road, Taichung 404, Taiwan
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Isobe K, Takahashi T, Ogawa J, Kataoka M, Shimizu S. Production and characterization of alcohol oxidase from Penicillium purpurescens AIU 063. J Biosci Bioeng 2009; 107:108-12. [DOI: 10.1016/j.jbiosc.2008.10.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Accepted: 10/21/2008] [Indexed: 10/20/2022]
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17
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Siderophore synthesis in Magnaporthe grisea is essential for vegetative growth, conidiation and resistance to oxidative stress. Fungal Genet Biol 2008; 46:321-32. [PMID: 19171198 DOI: 10.1016/j.fgb.2008.12.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2008] [Revised: 12/11/2008] [Accepted: 12/15/2008] [Indexed: 11/21/2022]
Abstract
The plant pathogenic fungus Magnaporthe grisea excretes siderophores of the coprogen-type for iron acquisition and uses ferricrocin for intracellular iron storage. In the present report we characterize mutants with defects in extracellular siderophore biosynthesis. Deletion of the M. grisea SSM2 gene, which encodes a non-ribosomal peptide synthetase, resulted in a loss of the production of all coprogens. The mutant strains had a reduced growth rate, produced fewer conidia and were more sensitive to oxidative stress. Ferricrocin production was not affected. Upon deletion of M. grisea OMO1, a gene predicted to encode an L-ornithine-N(5)-monooxygenase, no siderophores of any type were detected, the strain was aconidial, growth rate was reduced and sensitivity to oxidative stress was increased. Abundance of several proteins was affected in the mutants. The Deltassm2 and Deltaomo1 mutant phenotypes were complemented by supplementation of the medium with siderophores or reintroduction of the respective genes.
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Mondego JMC, Carazzolle MF, Costa GGL, Formighieri EF, Parizzi LP, Rincones J, Cotomacci C, Carraro DM, Cunha AF, Carrer H, Vidal RO, Estrela RC, García O, Thomazella DPT, de Oliveira BV, Pires AB, Rio MCS, Araújo MRR, de Moraes MH, Castro LAB, Gramacho KP, Gonçalves MS, Neto JPM, Neto AG, Barbosa LV, Guiltinan MJ, Bailey BA, Meinhardt LW, Cascardo JC, Pereira GAG. A genome survey of Moniliophthora perniciosa gives new insights into Witches' Broom Disease of cacao. BMC Genomics 2008; 9:548. [PMID: 19019209 PMCID: PMC2644716 DOI: 10.1186/1471-2164-9-548] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Accepted: 11/18/2008] [Indexed: 11/10/2022] Open
Abstract
Background The basidiomycete fungus Moniliophthora perniciosa is the causal agent of Witches' Broom Disease (WBD) in cacao (Theobroma cacao). It is a hemibiotrophic pathogen that colonizes the apoplast of cacao's meristematic tissues as a biotrophic pathogen, switching to a saprotrophic lifestyle during later stages of infection. M. perniciosa, together with the related species M. roreri, are pathogens of aerial parts of the plant, an uncommon characteristic in the order Agaricales. A genome survey (1.9× coverage) of M. perniciosa was analyzed to evaluate the overall gene content of this phytopathogen. Results Genes encoding proteins involved in retrotransposition, reactive oxygen species (ROS) resistance, drug efflux transport and cell wall degradation were identified. The great number of genes encoding cytochrome P450 monooxygenases (1.15% of gene models) indicates that M. perniciosa has a great potential for detoxification, production of toxins and hormones; which may confer a high adaptive ability to the fungus. We have also discovered new genes encoding putative secreted polypeptides rich in cysteine, as well as genes related to methylotrophy and plant hormone biosynthesis (gibberellin and auxin). Analysis of gene families indicated that M. perniciosa have similar amounts of carboxylesterases and repertoires of plant cell wall degrading enzymes as other hemibiotrophic fungi. In addition, an approach for normalization of gene family data using incomplete genome data was developed and applied in M. perniciosa genome survey. Conclusion This genome survey gives an overview of the M. perniciosa genome, and reveals that a significant portion is involved in stress adaptation and plant necrosis, two necessary characteristics for a hemibiotrophic fungus to fulfill its infection cycle. Our analysis provides new evidence revealing potential adaptive traits that may play major roles in the mechanisms of pathogenicity in the M. perniciosa/cacao pathosystem.
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Affiliation(s)
- Jorge M C Mondego
- Laboratório de Genômica e Expressão, Departamento de Genética e Evolução, Instituto de Biologia, Universidade Estadual de Campinas, CP 6109, 13083-970, Campinas, SP, Brazil.
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Kumar AK, Goswami P. Purification and properties of a novel broad substrate specific alcohol oxidase from Aspergillus terreus MTCC 6324. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1784:1552-9. [PMID: 18639656 DOI: 10.1016/j.bbapap.2008.06.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 06/04/2008] [Accepted: 06/05/2008] [Indexed: 11/18/2022]
Abstract
An alcohol oxidase was isolated from the microsome of n-hexadecane grown Aspergillus terreus and purified by ion exchange chromatography. The oxidase was found to act on short chain-, long chain-, secondary-, and aromatic-alcohol substrates with highest affinity for n-heptanol (K(M)=0.498 mM, K(cat)=2.7x10(2) s(-1)). The native protein molecular mass was 269+/-5 kDa and the subunit molecular masses were 85-, 63-, 43-, 27-, and 13-kDa. The isoelectric point of the proteins was within 8.3-8.5. High aggregating property of the protein was demonstrated by AFM, DLS and TEM analyses. Chemical analysis showed the presence of oleic acid and palmitic acid at a ratio of 2:1 in the purified protein. This lipoidic nature of the protein particles was correlated to the high aggregating property. In this flavoenzyme, flavin was non-covalently but avidly associated. Peptide mass fingerprinting studies showed the presence of two FAD binding domains in 63 kDa protein. Among these two FAD binding domain sequences only the YPVIDHEYDAVVVGAGGAGLR peptide shows 45-50% sequence homology with the reported N-terminal sequences of other known alcohol oxidases. Non-redundant database search of 63- and 43-kDa subunits peptide sequences showed no sequence similarity with the other alcohol oxidase protein reported till now.
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Affiliation(s)
- Adepu Kiran Kumar
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati-781039, Assam, India
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20
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Bolton MD, van Esse HP, Vossen JH, de Jonge R, Stergiopoulos I, Stulemeijer IJE, van den Berg GCM, Borrás-Hidalgo O, Dekker HL, de Koster CG, de Wit PJGM, Joosten MHAJ, Thomma BPHJ. The novel Cladosporium fulvum lysin motif effector Ecp6 is a virulence factor with orthologues in other fungal species. Mol Microbiol 2008; 69:119-36. [PMID: 18452583 DOI: 10.1111/j.1365-2958.2008.06270.x] [Citation(s) in RCA: 195] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
During tomato leaf colonization, the biotrophic fungus Cladosporium fulvum secretes several effector proteins into the apoplast. Eight effectors have previously been characterized and show no significant homology to each other or to other fungal genes. To discover novel C. fulvum effectors that might play a role in virulence, we utilized two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) to visualize proteins secreted during C. fulvum-tomato interactions. Three novel C. fulvum proteins were identified: CfPhiA, Ecp6 and Ecp7. CfPhiA shows homology to proteins found on fungal sporogenous cells called phialides. Ecp6 contains lysin motifs (LysM domains) that are recognized as carbohydrate-binding modules. Ecp7 encodes a small, cysteine-rich protein with no homology to known proteins. Heterologous expression of Ecp6 significantly increased the virulence of the vascular pathogen Fusarium oxysporum on tomato. Furthermore, by RNA interference (RNAi)-mediated gene silencing we demonstrate that Ecp6 is instrumental for C. fulvum virulence on tomato. Hardly any allelic variation was observed in the Ecp6 coding region of a worldwide collection of C. fulvum strains. Although none of the C. fulvum effectors identified so far have obvious orthologues in other organisms, conserved Ecp6 orthologues were identified in various fungal species. Homology-based modelling suggests that the LysM domains of C. fulvum Ecp6 may be involved in chitin binding.
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Affiliation(s)
- Melvin D Bolton
- Laboratory of Phytopathology, Wageningen University, Binnenhaven 5, Wageningen, The Netherlands
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Purification and characterization of alcohol oxidase from Paecilomyces variotii isolated as a formaldehyde-resistant fungus. Appl Microbiol Biotechnol 2008; 77:995-1002. [DOI: 10.1007/s00253-007-1237-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2007] [Revised: 10/01/2007] [Accepted: 10/03/2007] [Indexed: 10/22/2022]
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Daniel G, Volc J, Filonova L, Plíhal O, Kubátová E, Halada P. Characteristics of Gloeophyllum trabeum alcohol oxidase, an extracellular source of H2O2 in brown rot decay of wood. Appl Environ Microbiol 2007; 73:6241-53. [PMID: 17660304 PMCID: PMC2075019 DOI: 10.1128/aem.00977-07] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2007] [Accepted: 07/23/2007] [Indexed: 11/20/2022] Open
Abstract
A novel alcohol oxidase (AOX) has been purified from mycelial pellets of the wood-degrading basidiomycete Gloeophyllum trabeum and characterized as a homooctameric nonglycosylated protein with native and subunit molecular masses of 628 and 72.4 kDa, containing noncovalently bonded flavin adenine dinucleotide. The isolated AOX cDNA contained an open reading frame of 1,953 bp translating into a polypeptide of 651 amino acids displaying 51 to 53% identity with other published fungal AOX amino acid sequences. The enzyme catalyzed the oxidation of short-chain primary aliphatic alcohols with a preference for methanol (K(m) = 2.3 mM, k(cat) = 15.6 s(-1)). Using polyclonal antibodies and immunofluorescence staining, AOX was localized on liquid culture hyphae and extracellular slime in sections from degraded wood and on cotton fibers. Transmission electron microscopy immunogold labeling localized the enzyme in the hyphal periplasmic space and wall and on extracellular tripartite membranes and slime, while there was no labeling of hyphal peroxisomes. AOX was further shown to be associated with membranous or slime structures secreted by hyphae in wood fiber lumina and within the secondary cell walls of degraded wood fibers. The differences in AOX targeting compared to the known yeast peroxisomal localization were traced to a unique C-terminal sequence of the G. trabeum oxidase, which is apparently responsible for the protein's different translocation. The extracellular distribution and the enzyme's abundance and preference for methanol, potentially available from the demethylation of lignin, all point to a possible role for AOX as a major source of H(2)O(2), a component of Fenton's reagent implicated in the generally accepted mechanisms for brown rot through the production of highly destructive hydroxyl radicals.
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Affiliation(s)
- Geoffrey Daniel
- Department of Forest Products/Wood Science, Swedish University of Agricultural Sciences, P.O. Box 7008, SE-750 07 Uppsala, Sweden.
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Isobe K, Kato A, Sasaki Y, Suzuki S, Kataoka M, Ogawa J, Iwasaki A, Hasegawa J, Shimizu S. Purification and characterization of a novel alcohol oxidase from Paenibacillus sp. AIU 311. J Biosci Bioeng 2007; 104:124-8. [PMID: 17884657 DOI: 10.1263/jbb.104.124] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2007] [Accepted: 05/16/2007] [Indexed: 11/17/2022]
Abstract
An oxidase catalyzing the conversion of glycolaldehyde to glyoxal was purified to the homogeneous state from Paenibacillus sp. AIU 311, and its properties were revealed. This enzyme was specific to glycolaldehyde and glyceraldehyde, and the reaction rates to other alcohols and aldehydes were less than 6% of that of glycolaldehyde. The Km values for glycolaldehyde and glyceraldehyde were estimated to be 13.2 and 7.5 mM, respectively. The glycolaldehyde oxidation was optimum at pH 6.5 and 50 degrees C. The molecular mass of this enzyme was 49 kDa, and it consisted of two identical subunits of 24 kDa. The NH2-terminal sequence was not homologous to those of alcohol oxidases. This is the first report of an oxidase exhibiting high specificity to a hydroxy group of aldehyde alcohols.
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Affiliation(s)
- Kimiyasu Isobe
- Department of Agro-bioscience, Iwate University, 3-18-8 Ueda, Morioka 020-8550, Japan.
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Isobe K, Kato A, Ogawa J, Kataoka M, Iwasaki A, Hasegawa J, Shimizu S. Characterization of alcohol oxidase from Aspergillus ochraceus AIU 031. J GEN APPL MICROBIOL 2007; 53:177-83. [PMID: 17726298 DOI: 10.2323/jgam.53.177] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
An alcohol oxidase (AOD) was found from Aspergillus ochraceus AIU 031, and its characteristics were revealed. This enzyme oxidized short-chain primary alcohols and ethylene glycol, and belonged to the same group as AOD from methylotrophic yeast. However, it differed in the following properties. The K(m) value for ethanol was larger and that for ethylene glycol was smaller than those of AODs derived from methylotrophic yeasts. The ethanol oxidation was optimal at pH 5-7 and 50-55 degrees C. The molecular mass of this enzyme was 262 kDa and consisted of four identical subunits of 68 kDa, which were much smaller than those of methylotrophic yeasts.
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Affiliation(s)
- Kimiyasu Isobe
- Department of Agro-bioscience, Iwate University, Ueda, Morioka, Japan.
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Bailey BA, Bae H, Strem MD, Roberts DP, Thomas SE, Crozier J, Samuels GJ, Choi IY, Holmes KA. Fungal and plant gene expression during the colonization of cacao seedlings by endophytic isolates of four Trichoderma species. PLANTA 2006; 224:1449-64. [PMID: 16832690 DOI: 10.1007/s00425-006-0314-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2006] [Accepted: 04/18/2006] [Indexed: 05/10/2023]
Abstract
Endophytic isolates of Trichoderma species are being considered as biocontrol agents for diseases of Theobroma cacao (cacao). Gene expression was studied during the interaction between cacao seedlings and four endophytic Trichoderma isolates, T. ovalisporum-DIS 70a, T. hamatum-DIS 219b, T. harzianum-DIS 219f, and Trichoderma sp.-DIS 172ai. Isolates DIS 70a, DIS 219b, and DIS 219f were mycoparasitic on the pathogen Moniliophthora roreri, and DIS 172ai produced metabolites that inhibited growth of M. roreri in culture. ESTs (116) responsive to endophytic colonization of cacao were identified using differential display and their expression analyzed using macroarrays. Nineteen cacao ESTs and 17 Trichoderma ESTs were chosen for real-time quantitative PCR analysis. Seven cacao ESTs were induced during colonization by the Trichoderma isolates. These included putative genes for ornithine decarboxylase (P1), GST-like proteins (P4), zinc finger protein (P13), wound-induced protein (P26), EF-calcium-binding protein (P29), carbohydrate oxidase (P59), and an unknown protein (U4). Two plant ESTs, extensin-like protein (P12) and major intrinsic protein (P31), were repressed due to colonization. The plant gene expression profile was dependent on the Trichoderma isolate colonizing the cacao seedling. The fungal ESTs induced in colonized cacao seedlings also varied with the Trichoderma isolate used. The most highly induced fungal ESTs were putative glucosyl hydrolase family 2 (F3), glucosyl hydrolase family 7 (F7), serine protease (F11), and alcohol oxidase (F19). The pattern of altered gene expression suggests a complex system of genetic cross talk occurs between the cacao tree and Trichoderma isolates during the establishment of the endophytic association.
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Affiliation(s)
- B A Bailey
- Sustainable Perennial Crops Laboratory, BARC-West, Beltsville, MD 20705, USA.
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Szamecz B, Urbán G, Rubiera R, Kucsera J, Dorgai L. Identification of four alcohol oxidases from methylotrophic yeasts. Yeast 2005; 22:669-76. [PMID: 16032762 DOI: 10.1002/yea.1236] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Three yeast strains capable of utilizing methanol as sole carbon and energy source were isolated. Two were classified as Candida boidinii, while the third belonged in the genus Pichia. From these three strains, four alcohol oxidases genes were identified and the sequences of the coding regions were determined: one from each Candida boidinii (aox0673 and aox0680) and two from Pichia sp. 159 (aoxA and aoxB). Methanol induces both alcohol oxidases in Pichia sp. 159: the levels of aoxA and aoxB mRNA reach about 100% and 300%, respectively, of that of his4 mRNA. aoxA, but not aoxB, is expressed at a low level in the presence of glucose. The newly described alcohol oxidases have proper dinucleotide binding sites and PTS1-like C-terminal tripeptides, identified as important elements for peroxisomal localization.
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Affiliation(s)
- Béla Szamecz
- Department of Molecular Biotechnology, Bay Zoltán Institute for Biotechnology, Derkovits Fasor 2, H-6726 Szeged, Hungary
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Ozimek P, Veenhuis M, van der Klei IJ. Alcohol oxidase: a complex peroxisomal, oligomeric flavoprotein. FEMS Yeast Res 2005; 5:975-83. [PMID: 16169288 DOI: 10.1016/j.femsyr.2005.06.005] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Revised: 06/07/2005] [Accepted: 06/07/2005] [Indexed: 10/25/2022] Open
Abstract
Alcohol oxidase (AO) is the key enzyme of methanol metabolism in methylotrophic yeast species. It catalyses the first step of methanol catabolism, namely its oxidation to formaldehyde with concomitant production of hydrogen peroxide. In its mature active form, AO is a molecule of high molecular mass (600 kDa) that consists of eight identical subunits, each of which carry one non-covalently bound flavin adenine nucleotide (FAD) molecule as the prosthetic group. In vivo, the protein is compartmentalized into special cell organelles, termed peroxisomes. AO is an abundant protein and its synthesis is strictly regulated by repression/derepression and induction mechanisms that occur at the transcriptional level. Various aspects of its sorting and assembly/activation render AO a unique protein. Recent developments of AO synthesis, sorting and assembly/activation are highlighted in this paper.
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Affiliation(s)
- Paulina Ozimek
- Eukaryotic Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, P.O. Box 14, 9750 AA Haren, The Netherlands
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Thomma BPHJ, VAN Esse HP, Crous PW, DE Wit PJGM. Cladosporium fulvum (syn. Passalora fulva), a highly specialized plant pathogen as a model for functional studies on plant pathogenic Mycosphaerellaceae. MOLECULAR PLANT PATHOLOGY 2005; 6:379-93. [PMID: 20565665 DOI: 10.1111/j.1364-3703.2005.00292.x] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
UNLABELLED SUMMARY Taxonomy: Cladosporium fulvum is an asexual fungus for which no sexual stage is currently known. Molecular data, however, support C. fulvum as a member of the Mycosphaerellaceae, clustering with other taxa having Mycosphaerella teleomorphs. C. fulvum has recently been placed in the anamorph genus Passalora as P. fulva. Its taxonomic disposition is supported by its DNA phylogeny, as well as the distinct scars on its conidial hila, which are typical of Passalora, and unlike Cladosporium s.s., which has teleomorphs that reside in Davidiella, and not Mycosphaerella. Host range and disease symptoms: The presently known sole host of C. fulvum is tomato (members of the genusLycopersicon). C. fulvum is mainly a foliar pathogen. Disease symptoms are most obvious on the abaxial side of the leaf and include patches of white mould that turn brown upon sporulation. Due to stomatal clogging, curling of leaves and wilting can occur, leading to defoliation. C. fulvum as a model pathogen: The interaction between C. fulvum and tomato is governed by a gene-for-gene relationship. A total of eight Avr and Ecp genes, and for four of these also the corresponding plant Cf genes, have been cloned. Obtaining conclusive evidence for gene-for-gene relationships is complicated by the poor availability of genetic tools for most Mycosphaerellaceae-plant interactions. Newly developed tools, including Agrobacterium-mediated transformation and RNAi, added to the genome sequence of its host tomato, which will be available within a few years, render C. fulvum attractive as a model species for plant pathogenic Mycosphaerellaceae. USEFUL WEBSITES http://www.sgn.cornell.edu/help/about/index.html; http://cogeme.ex.ac.uk.
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Affiliation(s)
- Bart P H J Thomma
- Laboratory of Phytopathology, Wageningen University, Binnenhaven 5, 6709 PD Wageningen, The Netherlands
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Guilleroux M, Osbourn A. Gene expression during infection of wheat roots by the 'take-all' fungus Gaeumannomyces graminis. MOLECULAR PLANT PATHOLOGY 2004; 5:203-16. [PMID: 20565610 DOI: 10.1111/j.1364-3703.2004.00219.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
SUMMARY The infection of plants by pathogenic microbes and the subsequent establishment of disease involves substantial changes in the biochemistry and physiology of both partners. Analysis of genes that are expressed during these interactions represents a powerful strategy to obtain insights into the molecular events underlying these changes. Root diseases have considerable economic impact but have not been characterized extensively at the molecular genetic level. Here we have used two complementary approaches-suppression subtractive hybridization and expressed sequence tag analysis of an unsubtracted cDNA library-to investigate gene expression during the early stages of colonization of wheat roots by the take-all fungus, Gaeumannomyces graminis.
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Affiliation(s)
- M Guilleroux
- IBP, Bat 630, Université Paris Sud, Orsay 91405, France
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Gardiner DM, Howlett BJ. Negative selection using thymidine kinase increases the efficiency of recovery of transformants with targeted genes in the filamentous fungus Leptosphaeria maculans. Curr Genet 2004; 45:249-55. [PMID: 14749893 DOI: 10.1007/s00294-004-0488-6] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2003] [Revised: 12/09/2003] [Accepted: 01/05/2004] [Indexed: 11/27/2022]
Abstract
A vector system was constructed that is designed to decrease the number of transformants required to be screened when looking for gene disruption events in filamentous fungi. This vector was used to mutate two genes, an ATP-binding cassette transporter ( LmABCt4) and a two-component histidine kinase gene ( LmHK1) in the ascomycete Leptosphaeria maculans. The system uses the thymidine kinase gene from the herpes simplex virus as a negative selectable marker. Thymidine kinase expression is regulated by the TrpC regulatory elements from Aspergillus nidulans and should be applicable to other ascomycetous fungi. When thymidine kinase is expressed in the presence of particular thymidine analogues, these analogues are converted to toxic compounds which kill the cell. We also report the transformation of L. maculans using Agrobacterium tumefaciens-mediated DNA delivery.
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Affiliation(s)
- Donald M Gardiner
- School of Botany, The University of Melbourne, 3010, Melbourne, Victoria, Australia.
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Bakkeren G, Gold S. The path in fungal plant pathogenicity: many opportunities to outwit the intruders? GENETIC ENGINEERING 2004; 26:175-223. [PMID: 15387298 DOI: 10.1007/978-0-306-48573-2_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
The number of genes implicated in the infection and disease processes of phytopathogenic fungi is increasing rapidly. Forward genetic approaches have identified mutated genes that affect pathogenicity, host range, virulence and general fitness. Likewise, candidate gene approaches have been used to identify genes of interest based on homology and recently through 'comparative genomic approaches' through analysis of large EST databases and whole genome sequences. It is becoming clear that many genes of the fungal genome will be involved in the pathogen-host interaction in its broadest sense, affecting pathogenicity and the disease process in planta. By utilizing the information obtained through these studies, plants may be bred or engineered for effective disease resistance. That is, by trying to disable pathogens by hitting them where it counts.
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Affiliation(s)
- Guus Bakkeren
- Agriculture & Agri-Food Canada,Pacific Agri-Food Research Centre, Summerland, BC, Canada V0H 1Z0
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Recorbet G, Steinberg C, Olivain C, Edel V, Trouvelot S, Dumas-Gaudot E, Gianinazzi S, Alabouvette C. Wanted: pathogenesis-related marker molecules for Fusarium oxysporum. THE NEW PHYTOLOGIST 2003; 159:73-92. [PMID: 33873682 DOI: 10.1046/j.1469-8137.2003.00795.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Although Fusarium oxysporum pathogens cause severe wilts in about 80 botanical species, the mechanisms of pathogenicity and symptom induction are poorly understood. Knowledge about the genetic and biochemical pathways involved in the pathogenesis of F. oxysporum would be invaluable in getting targets for both fungicide development and search for biocontrol agents. In this respect, we described the main approaches that have been developed to identify some mechanisms underlying the pathogenesis of F. oxysporum. During the last decades, the potential functions triggering of F. oysporum pathogenicity have mainly been investigated by comparing soilborne pathogenic strains with nonpathogenic ones with regards to the analysis of the pre- and infection stages and of the resulting plant-fungus interactions. The relatively recent progress in the molecular biology of this fungus has allowed complementary approaches to be developed in order to identify key factors involved in F. oxysporum pathogenicity. Screening mutants of F. oxysporum for loss of virulence led to the successful identification of some pathogenesis-related factors, such as hydrophobicity or attachment of germlings. Taken together, the strategies described above support the idea that changes in fungal metabolism is also of importance in triggering of F. oxysporum pathogenesis.
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Affiliation(s)
- Ghislaine Recorbet
- Unité Mixte de Recherche 1088, INRA/Université de Bourgogne: Biochimie, Biologie Cellulaire et Ecologie des Interactions Plantes/Micro-Organismes, INRA-CMSE, BP 86510, 21065 Dijon Cedex, France
| | - Christian Steinberg
- Unité Mixte de Recherche 1088, INRA/Université de Bourgogne: Biochimie, Biologie Cellulaire et Ecologie des Interactions Plantes/Micro-Organismes, INRA-CMSE, BP 86510, 21065 Dijon Cedex, France
| | - Chantal Olivain
- Unité Mixte de Recherche 1088, INRA/Université de Bourgogne: Biochimie, Biologie Cellulaire et Ecologie des Interactions Plantes/Micro-Organismes, INRA-CMSE, BP 86510, 21065 Dijon Cedex, France
| | - Véronique Edel
- Unité Mixte de Recherche 1088, INRA/Université de Bourgogne: Biochimie, Biologie Cellulaire et Ecologie des Interactions Plantes/Micro-Organismes, INRA-CMSE, BP 86510, 21065 Dijon Cedex, France
| | - Sophie Trouvelot
- Unité Mixte de Recherche 1088, INRA/Université de Bourgogne: Biochimie, Biologie Cellulaire et Ecologie des Interactions Plantes/Micro-Organismes, INRA-CMSE, BP 86510, 21065 Dijon Cedex, France
| | - Eliane Dumas-Gaudot
- Unité Mixte de Recherche 1088, INRA/Université de Bourgogne: Biochimie, Biologie Cellulaire et Ecologie des Interactions Plantes/Micro-Organismes, INRA-CMSE, BP 86510, 21065 Dijon Cedex, France
| | - Silvio Gianinazzi
- Unité Mixte de Recherche 1088, INRA/Université de Bourgogne: Biochimie, Biologie Cellulaire et Ecologie des Interactions Plantes/Micro-Organismes, INRA-CMSE, BP 86510, 21065 Dijon Cedex, France
| | - Claude Alabouvette
- Unité Mixte de Recherche 1088, INRA/Université de Bourgogne: Biochimie, Biologie Cellulaire et Ecologie des Interactions Plantes/Micro-Organismes, INRA-CMSE, BP 86510, 21065 Dijon Cedex, France
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Solomon PS, Tan KC, Oliver RP. The nutrient supply of pathogenic fungi; a fertile field for study. MOLECULAR PLANT PATHOLOGY 2003; 4:203-10. [PMID: 20569380 DOI: 10.1046/j.1364-3703.2003.00161.x] [Citation(s) in RCA: 108] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
SUMMARY Phytopathogenic fungi must feed on their hosts to propagate and cause disease. Their ability to access the rich nutrient supply offered by living plants is one of the most obvious properties that distinguish pathogens from saprophytes. Successful invasion by pathogens depends as much on their ability to utilize the available nutrient sources offered by plants as on their ability to penetrate plants and evade defensive mechanisms. Here, we review current knowledge on the nature of the nutrient supplies utilized by pathogens during infection. The available evidence is rudimentary in most cases. There is much evidence to suggest that fungal metabolism can be divided into at least two phases. The first is based on lipolysis and occurs during germination and penetration of the host. The second phase uses glycolysis and predominates during the invasion of host tissue. We also propose, mainly on theoretical grounds, that a third phase of nutrition occurs late in infection during which new spores are produced. Contrary to early assumptions, the nitrogen sources available to some pathogens appear to be abundant. The idea that nitrogen starvation is a cue that controls fungal gene expression during infection may need to be reassessed. Very little is known about the micronutrient (Fe, S, P) or vitamin supply. The knowledge gained from this research may enable the design of new antifungal strategies targeting potential weaknesses in fungal metabolism and will also impact on agronomic practices.
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Affiliation(s)
- Peter S Solomon
- The Australian Centre for Necrotrophic Fungal Pathogens, SABC, DSE, Murdoch University, Perth 6150, Western Australia, Australia
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Abstract
Summary Recently many fungal genes have been identified that, when disrupted, result in strains with a reduction or total loss of disease symptoms. Such pathogenicity genes are the subject of this review. The large number of pathogenicity genes identified is due to the application of tagged mutagenesis techniques (random or targeted). Genes have been identified with roles in the formation of infection structures, cell wall degradation, overcoming or avoiding plant defences, responding to the host environment, production of toxins, and in signal cascades. Additionally, genes with no database matches and with 'novel' functions have also been found. Improved technologies for mutation analysis and for sequencing and analysing fungal genomes hold promise for identifying many more pathogenicity genes.
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Affiliation(s)
- A Idnurm
- School of Botany, The University of Melbourne, Parkville, Melbourne, Victoria 3010, Australia
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Bussink HJ, Oliver R. Identification of two highly divergent catalase genes in the fungal tomato pathogen, Cladosporium fulvum. EUROPEAN JOURNAL OF BIOCHEMISTRY 2001; 268:15-24. [PMID: 11121097 DOI: 10.1046/j.1432-1327.2001.01774.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Catalases of pathogenic micro-organisms have attracted attention as potential virulence factors. Homology-based screens were performed to identify catalase genes in the fungal tomato pathogen Cladosporium fulvum. Two highly divergent genes, Cat1 and Cat2, were isolated and characterized. Cat1 codes for a putative 566-amino-acid catalase subunit and belongs to the gene family that also encodes the mainly peroxisome-localized catalases of animal and yeast species. Cat2 codes for a putative catalase subunit of 745 amino acids and belongs to a different gene family coding for the large-subunit catalases similar to ones found in bacteria and filamentous fungi. Neither catalase had an obvious secretory signal sequence. A search for an extracellular catalase was unproductive. The Cat1 and Cat2 genes showed differential expression, with the Cat1 mRNA preferentially accumulating in spores and the Cat2 mRNA preferentially accumulating in response to external H(2)O(2). With Cat2-deleted strains, activity of the Cat2 gene product (CAT2) was identified among four proteins with catalase activity separated on non-denaturing gels. The CAT2 activity represented a minor fraction of the catalase activity in spores and H(2)O(2)-stressed mycelium, and no phenotype was observed for Cat2-deleted strains, which showed a normal response to H(2)O(2) treatment. These results indicate the existence of a complex catalase system in C. fulvum, with regard to both the structure and regulation of the genes involved. In addition, efficient C. fulvum gene-replacement technology has been established.
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Affiliation(s)
- H J Bussink
- Carlsberg Laboratory, Department of Physiology, Copenhagen Valby, Denmark
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