1
|
Beck J, Fuhr O, Nieger M, Bräse S. A versatile Diels-Alder approach to functionalized hydroanthraquinones. ROYAL SOCIETY OPEN SCIENCE 2020; 7:200626. [PMID: 33391783 PMCID: PMC7735338 DOI: 10.1098/rsos.200626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 09/29/2020] [Indexed: 06/12/2023]
Abstract
The synthesis of highly substituted hydroanthraquinone derivatives with up to three stereogenic centres via a Diels-Alder reaction, starting from easily accessible 2-substituted naphthoquinones, is described. The [4+2]-cycloaddition is applicable for a broad range of substrates, runs under mild conditions and results in high yields. The highly regioselective outcome of the reactions is enabled by a benzoyl substituent at C2 of the dienophiles. The obtained hydroanthraquinones can be further modified and represent ideal substrates for follow-up intramolecular coupling reactions to create unique bicyclo[3.3.1] or -[3.2.2]nonane ring systems which are important natural product skeletons.
Collapse
Affiliation(s)
- Janina Beck
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany
| | - Olaf Fuhr
- Institute of Nanotechnology (INT) and Karlsruhe Nano-Micro Facility (KNMF), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Martin Nieger
- Department of Chemistry, University of Helsinki, PO Box 55 (A.I. Virtasen aukio 1), 00014 Helsinki, Finland
| | - Stefan Bräse
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany
- Institute of Biological and Chemical Systems-Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| |
Collapse
|
2
|
Rangel LI, Spanner RE, Ebert MK, Pethybridge SJ, Stukenbrock EH, de Jonge R, Secor GA, Bolton MD. Cercospora beticola: The intoxicating lifestyle of the leaf spot pathogen of sugar beet. MOLECULAR PLANT PATHOLOGY 2020; 21:1020-1041. [PMID: 32681599 PMCID: PMC7368123 DOI: 10.1111/mpp.12962] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/15/2020] [Accepted: 05/17/2020] [Indexed: 05/07/2023]
Abstract
Cercospora leaf spot, caused by the fungal pathogen Cercospora beticola, is the most destructive foliar disease of sugar beet worldwide. This review discusses C. beticola genetics, genomics, and biology and summarizes our current understanding of the molecular interactions that occur between C. beticola and its sugar beet host. We highlight the known virulence arsenal of C. beticola as well as its ability to overcome currently used disease management strategies. Finally, we discuss future prospects for the study and management of C. beticola infections in the context of newly employed molecular tools to uncover additional information regarding the biology of this pathogen. TAXONOMY Cercospora beticola Sacc.; Kingdom Fungi, Phylum Ascomycota, Class Dothideomycetes, Order Capnodiales, Family Mycosphaerellaceae, Genus Cercospora. HOST RANGE Well-known pathogen of sugar beet (Beta vulgaris subsp. vulgaris) and most species of the Beta genus. Reported as pathogenic on other members of the Chenopodiaceae (e.g., lamb's quarters, spinach) as well as members of the Acanthaceae (e.g., bear's breeches), Apiaceae (e.g., Apium), Asteraceae (e.g., chrysanthemum, lettuce, safflower), Brassicaceae (e.g., wild mustard), Malvaceae (e.g., Malva), Plumbaginaceae (e.g., Limonium), and Polygonaceae (e.g., broad-leaved dock) families. DISEASE SYMPTOMS Leaves infected with C. beticola exhibit circular lesions that are coloured tan to grey in the centre and are often delimited by tan-brown to reddish-purple rings. As disease progresses, spots can coalesce to form larger necrotic areas, causing severely infected leaves to wither and die. At the centre of these spots are black spore-bearing structures (pseudostromata). Older leaves often show symptoms first and younger leaves become infected as the disease progresses. MANAGEMENT Application of a mixture of fungicides with different modes of action is currently performed although elevated resistance has been documented in most employed fungicide classes. Breeding for high-yielding cultivars with improved host resistance is an ongoing effort and prudent cultural practices, such as crop rotation, weed host management, and cultivation to reduce infested residue levels, are widely used to manage disease. USEFUL WEBSITE: https://www.ncbi.nlm.nih.gov/genome/11237?genome_assembly_id=352037.
Collapse
Affiliation(s)
- Lorena I. Rangel
- Northern Crop Science LaboratoryU.S. Department of Agriculture ‐ Agricultural Research ServiceFargoNDUSA
| | - Rebecca E. Spanner
- Northern Crop Science LaboratoryU.S. Department of Agriculture ‐ Agricultural Research ServiceFargoNDUSA
- Department of Plant PathologyNorth Dakota State UniversityFargoNDUSA
| | - Malaika K. Ebert
- Northern Crop Science LaboratoryU.S. Department of Agriculture ‐ Agricultural Research ServiceFargoNDUSA
- Department of Plant PathologyNorth Dakota State UniversityFargoNDUSA
- Present address:
Department of Plant BiologyMichigan State UniversityEast LansingMIUSA
| | - Sarah J. Pethybridge
- Plant Pathology & Plant‐Microbe Biology SectionSchool of Integrative Plant ScienceCornell AgriTech at The New York State Agricultural Experiment StationCornell UniversityGenevaNYUSA
| | - Eva H. Stukenbrock
- Environmental Genomics GroupMax Planck Institute for Evolutionary BiologyPlönGermany
- Christian‐Albrechts University of KielKielGermany
| | - Ronnie de Jonge
- Department of Plant‐Microbe InteractionsUtrecht UniversityUtrechtNetherlands
| | - Gary A. Secor
- Department of Plant PathologyNorth Dakota State UniversityFargoNDUSA
| | - Melvin D. Bolton
- Northern Crop Science LaboratoryU.S. Department of Agriculture ‐ Agricultural Research ServiceFargoNDUSA
- Department of Plant PathologyNorth Dakota State UniversityFargoNDUSA
| |
Collapse
|
3
|
Gutiérrez-Nájera NA, Saucedo-García M, Noyola-Martínez L, Vázquez-Vázquez C, Palacios-Bahena S, Carmona-Salazar L, Plasencia J, El-Hafidi M, Gavilanes-Ruiz M. Sphingolipid Effects on the Plasma Membrane Produced by Addition of Fumonisin B1 to Maize Embryos. PLANTS (BASEL, SWITZERLAND) 2020; 9:E150. [PMID: 31979343 PMCID: PMC7076497 DOI: 10.3390/plants9020150] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 01/13/2020] [Accepted: 01/15/2020] [Indexed: 12/15/2022]
Abstract
Fumonisin B1 is a mycotoxin produced by Fusarium verticillioides that modifies the membrane properties from animal cells and inhibits complex sphingolipids synthesis through the inhibition of ceramide synthase. The aim of this work was to determine the effect of Fumonisin B1 on the plant plasma membrane when the mycotoxin was added to germinating maize embryos. Fumonisin B1 addition to the embryos diminished plasma membrane fluidity, increased electrolyte leakage, caused a 7-fold increase of sphinganine and a small decrease in glucosylceramide in the plasma membrane, without affecting phytosphingosine levels or fatty acid composition. A 20%-30% inhibition of the plasma membrane H+-ATPase activity was observed when embryos were germinated in the presence of the mycotoxin. Such inhibition was only associated to the decrease in glucosylceramide and the addition of exogenous ceramide to the embryos relieved the inhibition of Fumonisin B1. These results indicate that exposure of the maize embryos for 24 h to Fumonisin B1 allowed the mycotoxin to target ceramide synthase at the endoplasmic reticulum, eliciting an imbalance of endogenous sphingolipids. The latter disrupted membrane properties and inhibited the plasma membrane H+-ATPase activity. Altogether, these results illustrate the mode of action of the pathogen and a plant defense strategy.
Collapse
Affiliation(s)
- Nora A. Gutiérrez-Nájera
- Instituto Nacional de Medicina Genómica. Periférico Sur 4124, Torre 2, 5° piso. Álvaro Obregón 01900, Cd. de México, Mexico;
| | - Mariana Saucedo-García
- Instituto de Ciencias Agropecuarias, Universidad Autónoma del Estado de Hidalgo, Avenida Universidad Km. 1, Rancho Universitario, Tulancingo-Santiago, Tulantepec, Tulancingo 43600, Hidalgo, Mexico;
| | - Liliana Noyola-Martínez
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| | - Christian Vázquez-Vázquez
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| | - Silvia Palacios-Bahena
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| | - Laura Carmona-Salazar
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| | - Javier Plasencia
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| | - Mohammed El-Hafidi
- Departamento de Bioquímica. Instituto Nacional de Cardiología “Ignacio Chávez”. Juan Badiano 1. Tlalpan 14080, Cd. de México, Mexico;
| | - Marina Gavilanes-Ruiz
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| |
Collapse
|
4
|
Cercospora sp. as a source of anti-aging polyketides targeting 26S proteasome and scale-up production in submerged bioreactor. J Biotechnol 2019; 301:88-96. [PMID: 31152756 DOI: 10.1016/j.jbiotec.2019.05.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 05/14/2019] [Accepted: 05/27/2019] [Indexed: 12/31/2022]
Abstract
From a large screening of microbial extracts for the discovery of proteasome modulating natural products, the fungal strain Cercospora sp. (CF-223709) was selected as the most promising for further investigation. Different liquid cultures of the strain were initially screened for their anti-oxidant activity (DPPH, ABTS) and for their cytotoxicity against the A2058, HepG2 and CCD25sk cell lines. A detailed chemical analysis and evaluation of the capacity to activate 26S-proteasome was followed for the most active extract. Three main polyketides were isolated and characterized by extensive analysis of NMR and HRMS spectra data as penialidine F (1), fulvic acid (2), and SB238569 (3). Fulvic acid showed the most significant anti-oxidant activity. Its IC50 value (8.16 μM) against the ABTS radical resulted 3-fold lower than the standard trolox. Fulvic acid also demonstrated a significant effect on proteasome by enhancing the chymotrypsin- and caspase-like activities of the 26S proteasome of human fibroblasts by 71.43% and 37.5% at 1 μM, respectively. Furthermore by scaling up the culture in a 30 L submerged bioreactor, Cercospora sp. produced up to 162.6 ± 1.3 mg of fulvic acid/L. Our findings suggest that CF-223709 can be a promising source of proteasome activating natural compounds.
Collapse
|
5
|
Holmbo SD, Pronin SV. A Concise Approach to Anthraquinone-Xanthone Heterodimers. J Am Chem Soc 2018; 140:5065-5068. [PMID: 29621399 DOI: 10.1021/jacs.8b03110] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A synthetic approach to anthraquinone-xanthone heterodimers is described. The route to the pentacyclic core features an efficient assembly of a benzocycloheptenone via a new intramolecular oxidative arylation of an enol ether and a Hauser-Kraus annulation-aldol reaction sequence to access the characteristic bicyclo[3.2.2]nonene motif. Acremoxanthone A is synthesized in 10 steps from commercially available material to demonstrate the application of this approach.
Collapse
Affiliation(s)
- Stephen D Holmbo
- Department of Chemistry , University of California , Irvine , California 92697-2025 , United States
| | - Sergey V Pronin
- Department of Chemistry , University of California , Irvine , California 92697-2025 , United States
| |
Collapse
|
6
|
Geiger L, Nieger M, Bräse S. Suzuki-Miyaura Cross-Coupling Reactions of Tetrahydroxanthones and 4-Chromanone Lactones to Heteromeric Biaryls. Adv Synth Catal 2017. [DOI: 10.1002/adsc.201700497] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Larissa Geiger
- Institute of Organic Chemistry; Karlsruhe Institute of Technology (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Martin Nieger
- Department of Chemistry; University of Helsinki; P. O. Box 55 00014 University of Helsinki Finland
| | - Stefan Bräse
- Institute of Organic Chemistry; Karlsruhe Institute of Technology (KIT); Fritz-Haber-Weg 6 76131 Karlsruhe Germany
- Institute of Toxicology and Genetics; Karlsruhe Institute of Technology (KIT); Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
| |
Collapse
|
7
|
Geiger L, Nieger M, Bräse S. Scope and Limitations of the Domino Vinylogous Aldol/ oxa-Michael Reaction. ChemistrySelect 2017. [DOI: 10.1002/slct.201700667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Larissa Geiger
- Karlsruhe Institute of Technology; Institute of Organic Chemistry; Fritz-Haber-Weg 6 76131 Karlsruhe Germany
| | - Martin Nieger
- Department of Chemistry; University of Helsinki; P.O. Box 55 (A.I. Virtasen aukio 1), FIN- 00014 University of Helsinki Finland
| | - Stefan Bräse
- Karlsruhe Institute of Technology; Institute of Organic Chemistry; Fritz-Haber-Weg 6 76131 Karlsruhe Germany
- Karlsruhe Institute of Technology; Institute of Toxicology and Genetics; Hermann-von-Helmholtz-Platz 1, D- 76344 Eggenstein-Leopoldshafen Germany
| |
Collapse
|
8
|
Huggins TM, Whiteley JM, Love CT, Lee K, Lee SH, Ren ZJ, Biffinger JC. Controlled Growth of Nanostructured Biotemplates with Cobalt and Nitrogen Codoping as a Binderless Lithium-Ion Battery Anode. ACS APPLIED MATERIALS & INTERFACES 2016; 8:26868-26877. [PMID: 27636014 DOI: 10.1021/acsami.6b09300] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Biomass can serve as a sustainable template for the synthesis of carbon materials but is limited by the intrinsic properties of the precursor organism. In this study we demonstrate that the properties of a fungal biotemplate can be tuned during cultivation, establishing a new electrode manufacturing process and ultimately improving the electrochemical performance of the biomass-derived electrode. More specifically, the carbon/nitrogen ratio of Neurospora crassa mycelia mats was shifted by 5-fold while generating cobalt nanoparticles into the hyphal structure originating from macroconidia spores. This shift was achieved through nitrate limitation and equal molar concentrations of Mg2+ and Co2+ in the growth media. The resulting mycelia mat was converted via a high-temperature pyrolysis process (800 °C) to produce a freestanding cobalt and nitrogen codoped electrode material with no postmodification. Ultimately, nitrogen doping resulted in one of the highest recorded specific reversible capacity for a freestanding biomass-derived lithium-ion anode (400 mAh g-1 at C/10). We observed an additional improvement in capacity to 425 mAh g-1 with the incorporation of 3 wt % Co. Our results show how shaping the chemical characteristics of an electrode during the growth of the biotemplate allows for sustainable carbon-based material manufacturing from a living (self-assembled) material.
Collapse
Affiliation(s)
| | | | - Corey T Love
- Chemistry Department, U.S. Naval Research Laboratory , Washington, District of Columbia 20375, United States
| | - Kwangwon Lee
- Department of Biology, Rutgers University , Camden, New Jersey 08102, United States
| | | | | | - Justin C Biffinger
- Chemistry Department, U.S. Naval Research Laboratory , Washington, District of Columbia 20375, United States
| |
Collapse
|
9
|
Kramer CS, Nieger M, Bräse S. Naphthoquinone Diels-Alder Reactions: Approaches to the ABC Ring System of Beticolin. European J Org Chem 2014. [DOI: 10.1002/ejoc.201301763] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
10
|
Masters KS, Bräse S. Xanthones from fungi, lichens, and bacteria: the natural products and their synthesis. Chem Rev 2012; 112:3717-76. [PMID: 22617028 DOI: 10.1021/cr100446h] [Citation(s) in RCA: 291] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Kye-Simeon Masters
- Institute for Organic Chemistry, Karlsruhe Institute of Technology, Germany.
| | | |
Collapse
|
11
|
Duke SO, Dayan FE. Modes of action of microbially-produced phytotoxins. Toxins (Basel) 2011; 3:1038-1064. [PMID: 22069756 PMCID: PMC3202864 DOI: 10.3390/toxins3081038] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 08/15/2011] [Accepted: 08/17/2011] [Indexed: 01/17/2023] Open
Abstract
Some of the most potent phytotoxins are synthesized by microbes. A few of these share molecular target sites with some synthetic herbicides, but many microbial toxins have unique target sites with potential for exploitation by the herbicide industry. Compounds from both non-pathogenic and pathogenic microbes are discussed. Microbial phytotoxins with modes of action the same as those of commercial herbicides and those with novel modes of action of action are covered. Examples of the compounds discussed are tentoxin, AAL-toxin, auscaulitoxin aglycone, hydantocidin, thaxtomin, and tabtoxin.
Collapse
Affiliation(s)
- Stephen O. Duke
- United States Department of Agriculture, Agricultural Research Service, Natural Products Utilization Research Unit, P. O. Box 8048, MS 38677, USA;
| | | |
Collapse
|
12
|
Weltmeier F, Mäser A, Menze A, Hennig S, Schad M, Breuer F, Schulz B, Holtschulte B, Nehls R, Stahl DJ. Transcript profiles in sugar beet genotypes uncover timing and strength of defense reactions to Cercospora beticola infection. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2011; 24:758-72. [PMID: 21385013 DOI: 10.1094/mpmi-08-10-0189] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Cercospora leaf spot disease, caused by the fungus Cercospora beticola, is the most destructive foliar disease of sugar beet (Beta vulgaris) worldwide. Despite the great agronomical importance of this disease, little is known about its underlying molecular processes. Technical resources are scarce for analyzing this important crop species. We developed a sugar beet microarray with 44,000 oligonucleotides that represent 17,277 cDNAs. During the four stages of C. beticola-B. vulgaris interactions, we profiled the transcriptional responses of three genotypes: susceptible, polygenic partial resistance, and monogenic resistant. Similar genes were induced in all three genotypes during infection but with striking differences in timing. The monogenic resistant genotype displayed strong defense responses at 1 day postinoculation (dpi). The other genotypes displayed defense responses in a later phase (15 dpi) of the infection cycle. The partially resistant genotype displayed a strong defense response in the late phase of the infection cycle. Furthermore, the partially resistant genotype expressed pathogen-related transcripts that the susceptible genotype lacked. These results indicate that resistance was achieved by the ability to mount an early defense response, and partial resistance was determined by additional defense and signaling transcripts that allowed effective defense in the late phase of the infection cycle.
Collapse
|
13
|
Racapé J, Belbahri L, Engelhardt S, Lacombe B, Lee J, Lochman J, Marais A, Nicole M, Nürnberger T, Parlange F, Puverel S, Keller H. Ca2+-dependent lipid binding and membrane integration of PopA, a harpin-like elicitor of the hypersensitive response in tobacco. Mol Microbiol 2005; 58:1406-20. [PMID: 16313625 DOI: 10.1111/j.1365-2958.2004.04910.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
PopA is released by type III secretion from the bacterial plant pathogen Ralstonia solanacearum and triggers the hypersensitive response (HR) in tobacco. The function of PopA remains obscure, mainly because mutants lacking this protein are not altered in their ability to interact with plants. In an attempt to identify the site of PopA activity in plant cells, we generated transgenic tobacco plants expressing the popA gene under the control of an inducible promoter. Immunocytologic analysis revealed that the HR phenotype of these plants correlated with the presence of PopA at the plant plasma membrane. Membrane localization was observed irrespective of whether the protein was designed to accumulate in the cytoplasm or to be secreted by the plant cell, suggesting a general lipid-binding ability. We found that the protein had a high affinity for sterols and sphingolipids in vitro and that it required Ca2+ for both lipid binding and oligomerization. In addition, the protein was integrated into liposomes and membranes from Xenopus laevis oocytes where it formed ion-conducting pores. These characteristics suggest that PopA is part of a system that aims to attach the host cell plasma membrane and to allow molecules cross this barrier.
Collapse
Affiliation(s)
- Judith Racapé
- Unité Mixte de Recherches Interactions Plantes-Microorganismes et Santé Végétale, INRA-CNRS-UNSA, 400 Route des Chappes, 06903 Sophia Antipolis, France
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Weiland J, Koch G. Sugarbeet leaf spot disease (Cercospora beticola Sacc.)dagger. MOLECULAR PLANT PATHOLOGY 2004; 5:157-66. [PMID: 20565605 DOI: 10.1111/j.1364-3703.2004.00218.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
UNLABELLED SUMMARY Leaf spot disease caused by Cercospora beticola Sacc. is the most destructive foliar pathogen of sugarbeet worldwide. In addition to reducing yield and quality of sugarbeet, the control of leaf spot disease by extensive fungicide application incurs added costs to producers and repeatedly has selected for fungicide-tolerant C. beticola strains. The genetics and biochemistry of virulence have been examined less for C. beticola as compared with the related fungi C. nicotianae, C. kikuchii and C. zeae-maydis, fungi to which the physiology of C. beticola is often compared. C. beticola populations generally are not characterized as having race structure, although a case of race-specific resistance in sugarbeet to C. beticola has been reported. Resistance currently implemented in the field is quantitatively inherited and exhibits low to medium heritability. TAXONOMY Cercospora beticola Sacc.; Kingdom Fungi, Subdivision Deuteromycetes, Class Hyphomycetes, Order Hyphales, Genus Cercospora. IDENTIFICATION Circular, brown to red delimited spots with ashen-grey centre, 0.5-6 mm diameter; dark brown to black stromata against grey background; pale brown unbranched sparingly septate conidiophores, hyaline acicular conidia, multiseptate, from 2.5 to 4 microm wide and 50-200 microm long. HOST RANGE Propagative on Beta vulgaris and most species of Beta. Reported on members of the Chenopodiaceae and on Amaranthus. Disease symptoms: Infected leaves and petioles of B. vulgaris exhibit numerous circular leaf spots that coalesce in severe cases causing complete leaf collapse. Dark specks within a grey spot centre are characteristic for the disease. Older leaves exhibit a greater number of lesions with larger spot diameter. During the latter stage of severe epiphytotics, new leaf growth can be seen emerging from the plant surrounded by prostrate, collapsed leaves. CONTROL Fungicides in the benzimidazole and triazole class as well as organotin derivatives and strobilurins have successfully been used to control Cercospora leaf spot. Elevated levels of tolerance in populations of C. beticola to some of the chemicals registered for control has been documented. Partial genetic resistance also is used to reduce leaf spot disease.
Collapse
Affiliation(s)
- John Weiland
- United States Department of Agriculture, Agricultural Research Service, Northern Crop Science Laboratory, Fargo, ND 58105, USA
| | | |
Collapse
|
15
|
|
16
|
Gao Z, Xue Y, Dai J. The pathogenic site of the C-toxin derived fromBipolaris maydis race C in maize (Zea mays). CHINESE SCIENCE BULLETIN-CHINESE 2000. [DOI: 10.1007/bf02886268] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
17
|
Goudet C, Milat ML, Sentenac H, Thibaud JB. Beticolins, nonpeptidic, polycyclic molecules produced by the phytopathogenic fungus Cercospora beticola, as a new family of ion channel-forming toxins. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2000; 13:203-209. [PMID: 10659710 DOI: 10.1094/mpmi.2000.13.2.203] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Beticolins are toxins produced by Cercospora beticola, a phytopathogenic fungus responsible for the leaf spot disease of sugar beet. They form a family of 20 nonpeptidic compounds (named B0 to B19) that share the same polycyclic skeleton but differ by isomeric configuration (ortho- or para-) and by a variable residue R (bridging two carbons in one of the six cycles). It has been previously shown that B0 assembles itself into a multimeric structure and forms ion channels into planar lipid bilayers (C. Goudet, A.-A. Very, M.-L. Milat, M. Ildefonse, J.-B. Thibaud, H. Sentenac, and J.-P. Blein, Plant J. 14:359-364, 1998). In the present work, we investigate pore formation by three ortho-beticolins, B0, B2, and B4, and their related (i.e., same R) para-isomers, B13, B1, and B3, respectively, using planar lipid bilayers. All beticolins were able to form ion channels with multiple conductance states, although the type of cyclization (ortho- or para-) and residue (R) result in variations of channel conductance and ionic permeability, respectively. Channel formation by beticolins is likely to be involved in the biological activity of these toxins.
Collapse
Affiliation(s)
- C Goudet
- Laboratoire de Biochimie et Physiologie Moléculaire des Plantes, CNRS URA 2133/ENSA-M/INRA/UM2, Montpellier, France
| | | | | | | |
Collapse
|
18
|
Goudet C, Benitah JP, Milat ML, Sentenac H, Thibaud JB. Cluster organization and pore structure of ion channels formed by beticolin 3, a nonpeptidic fungal toxin. Biophys J 1999; 77:3052-9. [PMID: 10585927 PMCID: PMC1300576 DOI: 10.1016/s0006-3495(99)77136-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Beticolin 3 (B3) belongs to a family of nonpeptidic phytotoxins produced by the fungus Cercospora beticola, which present a broad spectrum of cytotoxic effects. We report here that, at cytotoxic concentration (10 microM), B3 formed voltage-independent, weakly selective ion channels with multiple conductance levels in planar lipid bilayers. In symmetrical standard solutions, conductance values of the first levels were, respectively, 16 +/- 1 pS, 32 +/- 2 pS, and 57 +/- 2 pS (n = 4) and so on, any conductance level being roughly twice the lower one. Whether a cluster organization of elementary channels or different channel structures underlies this particular property was addressed by investigating the ionic selectivity and the pore size corresponding to the first three conductance levels. Both selectivity and pore size were found to be almost independent of the conductance level. This indicated that multiple conductance behavior resulted from a cluster organization of "B3 elementary channels." According to the estimated pore size and analyses of x-ray diffraction of B3 microcrystals, a structural model for "B3 elementary channels" is proposed. The ability to form channels is likely to be involved in the biological activity of beticolins.
Collapse
Affiliation(s)
- C Goudet
- Laboratoire de Biochimie et Physiologie Moléculaire des Plantes, CNRS URA 2133/ENSA-M/INRA/UM2, 34060 Montpellier 1, France
| | | | | | | | | |
Collapse
|