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Stes E, Prinsen E, Holsters M, Vereecke D. Plant-derived auxin plays an accessory role in symptom development upon Rhodococcus fascians infection. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 70:513-527. [PMID: 22181713 DOI: 10.1111/j.1365-313x.2011.04890.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The biotrophic phytopathogen Rhodococcus fascians has a profound impact on plant development, mainly through its principal virulence factors, a mix of synergistically acting cytokinins that induce shoot formation. Expression profiling of marker genes for several auxin biosynthesis routes and mutant analysis demonstrated that the bacterial cytokinins stimulate the auxin biosynthesis of plants via specific targeting of the indole-3-pyruvic acid (IPA) pathway, resulting in enhanced auxin signaling in infected tissues. The double mutant tryptophan aminotransferase 1-1 tryptophan aminotransferase related 2-1 (taa1-1 tar2-1) of Arabidopsis (Arabidopsis thaliana), in which the IPA pathway is defective, displayed a decreased responsiveness towards R. fascians infection, although bacterial colonization and virulence gene expression were not impaired. These observations implied that plant-derived auxin was employed to reinforce symptom formation. Furthermore, the increased auxin production and, possibly, the accumulating bacterial cytokinins in infected plants modified the polar auxin transport so that new auxin maxima were repetitively established and distributed, a process that is imperative for symptom onset and maintenance. Based on these findings, we extend our model of the mode of action of bacterial and plant signals during the interaction between R. fascians and Arabidopsis.
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Affiliation(s)
- Elisabeth Stes
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Gent, Belgium
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Nissan G, Manulis-Sasson S, Chalupowicz L, Teper D, Yeheskel A, Pasmanik-Chor M, Sessa G, Barash I. The type III effector HsvG of the gall-forming Pantoea agglomerans mediates expression of the host gene HSVGT. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2012; 25:231-40. [PMID: 21995766 DOI: 10.1094/mpmi-06-11-0173] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The type III effector HsvG of the gall-forming Pantoea agglomerans pv. gypsophilae is a DNA-binding protein that is imported to the host nucleus and involved in host specificity. The DNA-binding region of HsvG was delineated to 266 amino acids located within a secondary structure region near the N-terminus of the protein but did not display any homology to canonical DNA-binding motifs. A binding site selection procedure was used to isolate a target gene of HsvG, named HSVGT, in Gypsophila paniculata. HSVGT is a predicted acidic protein of the DnaJ family with 244 amino acids. It harbors characteristic conserved motifs of a eukaryotic transcription factor, including a bipartite nuclear localization signal, zinc finger, and leucine zipper DNA-binding motifs. Quantitative real-time polymerase chain reaction analysis demonstrated that HSVGT transcription is specifically induced in planta within 2 h after inoculation with the wild-type P. agglomerans pv. gypsophilae compared with the hsvG mutant. Induction of HSVGT reached a peak of sixfold at 4 h after inoculation and progressively declined thereafter. Gel-shift assay demonstrated that HsvG binds to the HSVGT promoter, indicating that HSVGT is a direct target of HsvG. Our results support the hypothesis that HsvG functions as a transcription factor in gypsophila.
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Affiliation(s)
- Gal Nissan
- Department of Molecular Biology and Ecology of Plants, Tel-Aviv University, Tel-Aviv, Israel
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Arnold DL, Jackson RW. Bacterial genomes: evolution of pathogenicity. CURRENT OPINION IN PLANT BIOLOGY 2011; 14:385-91. [PMID: 21444240 DOI: 10.1016/j.pbi.2011.03.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2011] [Revised: 02/28/2011] [Accepted: 03/01/2011] [Indexed: 05/06/2023]
Abstract
Bacterial pathogens continue to pose a major threat to economically important plant resources. Disease outbreaks can occur through rapid evolution of a pathogen to overcome host defences. The advent of genome sequencing, especially next-generation technologies, has seen a revolution in the study of plant pathogen evolution over the past five years. This review highlights recent developments in understanding bacterial plant pathogen evolution, enabled by genomics and specifically focusing on type III protein effectors. The genotypic changes and mechanisms involved in pathogen evolution are now much better understood. However, there is still much to be learned about the drivers of pathogen evolution, both in terms of plant resistance and bacterial lifestyle.
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Affiliation(s)
- Dawn L Arnold
- Department of Applied Sciences, University of the West of England, Bristol, BS16 1QY, United Kingdom.
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Smits THM, Rezzonico F, Kamber T, Blom J, Goesmann A, Ishimaru CA, Frey JE, Stockwell VO, Duffy B. Metabolic versatility and antibacterial metabolite biosynthesis are distinguishing genomic features of the fire blight antagonist Pantoea vagans C9-1. PLoS One 2011; 6:e22247. [PMID: 21789243 PMCID: PMC3137637 DOI: 10.1371/journal.pone.0022247] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Accepted: 06/17/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Pantoea vagans is a commercialized biological control agent used against the pome fruit bacterial disease fire blight, caused by Erwinia amylovora. Compared to other biocontrol agents, relatively little is currently known regarding Pantoea genetics. Better understanding of antagonist mechanisms of action and ecological fitness is critical to improving efficacy. PRINCIPAL FINDINGS Genome analysis indicated two major factors Contribute to biocontrol activity: competition for limiting substrates and antibacterial metabolite production. Pathways for utilization of a broad diversity of sugars and acquisition of iron were identified. Metabolism of sorbitol by P. vagans C9-1 may be a major metabolic feature in biocontrol of fire blight. Biosynthetic genes for the antibacterial peptide pantocin A were found on a chromosomal 28-kb genomic island, and for dapdiamide E on the plasmid pPag2. There was no evidence of potential virulence factors that could enable an animal or phytopathogenic lifestyle and no indication of any genetic-based biosafety risk in the antagonist. CONCLUSIONS Identifying key determinants contributing to disease suppression allows the development of procedures to follow their expression in planta and the genome sequence contributes to rationale risk assessment regarding the use of the biocontrol strain in agricultural systems.
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Affiliation(s)
- Theo H. M. Smits
- Swiss National Competence Center for Fire Blight, Division of Plant Protection, Agroscope Changins-Wädenswil ACW, Wädenswil, Switzerland
| | - Fabio Rezzonico
- Swiss National Competence Center for Fire Blight, Division of Plant Protection, Agroscope Changins-Wädenswil ACW, Wädenswil, Switzerland
| | - Tim Kamber
- Swiss National Competence Center for Fire Blight, Division of Plant Protection, Agroscope Changins-Wädenswil ACW, Wädenswil, Switzerland
| | - Jochen Blom
- CeBiTec, Bielefeld University, Bielefeld, Germany
| | | | - Carol A. Ishimaru
- Department of Plant Pathology, University of Minnesota, St. Paul, Minnesota, United States of America
| | - Jürg E. Frey
- Swiss National Competence Center for Fire Blight, Division of Plant Protection, Agroscope Changins-Wädenswil ACW, Wädenswil, Switzerland
| | - Virginia O. Stockwell
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America
| | - Brion Duffy
- Swiss National Competence Center for Fire Blight, Division of Plant Protection, Agroscope Changins-Wädenswil ACW, Wädenswil, Switzerland
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55
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Vicente CSL, Nascimento F, Espada M, Mota M, Oliveira S. Bacteria associated with the pinewood nematode Bursaphelenchus xylophilus collected in Portugal. Antonie van Leeuwenhoek 2011; 100:477-81. [PMID: 21656192 DOI: 10.1007/s10482-011-9602-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Accepted: 05/30/2011] [Indexed: 10/18/2022]
Abstract
In this study, we report on the bacterial community associated with the pinewood nematode Bursaphelenchus xylophilus from symptomatic pine wilted trees, as well as from long-term preserved B. xylophilus laboratory collection specimens, emphasizing the close bacteria-nematode associations that may contribute to pine wilt disease development.
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Affiliation(s)
- Cláudia S L Vicente
- NemaLab, Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Évora, Portugal
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56
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Apine OA, Jadhav JP. Optimization of medium for indole-3-acetic acid production using Pantoea agglomerans strain PVM. J Appl Microbiol 2011; 110:1235-44. [PMID: 21332896 DOI: 10.1111/j.1365-2672.2011.04976.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To optimize the medium components for the production of indole-3-acetic acid (IAA) by isolated bacterium Pantoea agglomerans strain PVM. METHODS AND RESULTS Present study deals with the production of an essential plant hormone IAA by a bacterial isolate P. agglomerans strain PVM identified by 16S rRNA gene sequence analysis. The medium containing 8g l(-1) of meat extract and 1g l(-1) of l-tryptophan (precursor) at optimum pH 7, 30°C and 48-h incubation gave the maximum production of IAA (2·191 g l(-1) ). Effect of IAA synthesized on in vitro root induction in Nicotiana tobacum (leaf) explants was compared with that of control. IAA was characterized by high-performance thin-layer chromatography, high-performance liquid chromatography and gas chromatography-mass spectroscopy. CONCLUSIONS Pantoea agglomerans strain PVM was a good candidate for the inexpensive and utmost production of IAA in short period, as it requires simple medium (meat extract and l-tryptophan). SIGNIFICANCE AND IMPACT OF THE STUDY The present report first time showed the rapid, cost-effective and maximum production of IAA. No reports are available on the optimization of particular medium components for the production of IAA. This study demonstrates a novel approach for in vitro root induction in N. tobacum (leaf) explants.
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Affiliation(s)
- O A Apine
- Department of Biotechnology Shivaji University, Kolhapur, India
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Godfrey SAC, Lovell HC, Mansfield JW, Corry DS, Jackson RW, Arnold DL. The stealth episome: suppression of gene expression on the excised genomic island PPHGI-1 from Pseudomonas syringae pv. phaseolicola. PLoS Pathog 2011; 7:e1002010. [PMID: 21483484 PMCID: PMC3068993 DOI: 10.1371/journal.ppat.1002010] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Accepted: 01/29/2011] [Indexed: 11/18/2022] Open
Abstract
Pseudomonas syringae pv. phaseolicola is the causative agent of halo blight in the common bean, Phaseolus vulgaris. P. syringae pv. phaseolicola race 4 strain 1302A contains the avirulence gene avrPphB (syn. hopAR1), which resides on PPHGI-1, a 106 kb genomic island. Loss of PPHGI-1 from P. syringae pv. phaseolicola 1302A following exposure to the hypersensitive resistance response (HR) leads to the evolution of strains with altered virulence. Here we have used fluorescent protein reporter systems to gain insight into the mobility of PPHGI-1. Confocal imaging of dual-labelled P. syringae pv. phaseolicola 1302A strain, F532 (dsRFP in chromosome and eGFP in PPHGI-1), revealed loss of PPHGI-1::eGFP encoded fluorescence during plant infection and when grown in vitro on extracted leaf apoplastic fluids. Fluorescence-activated cell sorting (FACS) of fluorescent and non-fluorescent PPHGI-1::eGFP F532 populations showed that cells lost fluorescence not only when the GI was deleted, but also when it had excised and was present as a circular episome. In addition to reduced expression of eGFP, quantitative PCR on sub-populations separated by FACS showed that transcription of other genes on PPHGI-1 (avrPphB and xerC) was also greatly reduced in F532 cells harbouring the excised PPHGI-1::eGFP episome. Our results show how virulence determinants located on mobile pathogenicity islands may be hidden from detection by host surveillance systems through the suppression of gene expression in the episomal state. Bacterial pathogens evolve rapidly through the transfer of large segments, or genomic islands (GIs), of DNA. We study the mobility of an island named PPHGI-1 in Pseudomonas syringae pv. phaseolicola that causes halo-blight disease of bean. The exposure of P. syringae pv. phaseolicola to plant defenses triggers the excision of PPHGI-1, creation of a circular episomal form and finally deletion of the GI or its transfer to other bacteria. We planned to examine deletion of PPHGI-1 within infected leaves, and we generated strains that expressed differently coloured fluorescent proteins from genes in the island or elsewhere on the chromosome. Loss of the specific fluorescence derived from the GI was expected to show deletion of PPHGI-1. However, collecting fluorescent and non-fluorescent bacteria showed that PPHGI-1 was usually not lost, but expressed its component genes very poorly when in the circularized state. Bacteria were therefore able to carry a hidden suite of genes that become activated when re-inserted into the chromosome. The “stealthy” movement of the island is beneficial to P. syringae pv. phaseolicola because genes on PPHGI-1 encode proteins that activate plant defenses. Similar gene silencing on episomes may occur in other pathogens and contribute to the evolution of microbial pathogenicity to animals and plants.
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Affiliation(s)
- Scott A. C. Godfrey
- Faculty of Health and Life Sciences, University of the West of England, Bristol, United Kingdom
| | - Helen C. Lovell
- Faculty of Health and Life Sciences, University of the West of England, Bristol, United Kingdom
| | - John W. Mansfield
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - David S. Corry
- Faculty of Health and Life Sciences, University of the West of England, Bristol, United Kingdom
| | - Robert W. Jackson
- School of Biological Sciences, University of Reading, Reading, United Kingdom
| | - Dawn L. Arnold
- Faculty of Health and Life Sciences, University of the West of England, Bristol, United Kingdom
- * E-mail:
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Weinthal DM, Barash I, Tzfira T, Gaba V, Teper D, Sessa G, Manulis-Sasson S. Characterization of nuclear localization signals in the type III effectors HsvG and HsvB of the gall-forming bacterium Pantoea agglomerans. MICROBIOLOGY-SGM 2011; 157:1500-1508. [PMID: 21372093 DOI: 10.1099/mic.0.047118-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
HsvG and HsvB, two paralogous type III effectors of the gall-forming bacteria Pantoea agglomerans pv. gypsophilae and P. agglomerans pv. betae, determine host specificity on gypsophila and beet, respectively. They were previously shown to be DNA-binding proteins imported into host and non-host nuclei and might act as transcriptional activators. Sequence analysis of these effectors did not detect canonical nuclear localization signals (NLSs), but two basic amino acid clusters designated putative NLS1 and NLS2 were detected in their N-terminal and C-terminal regions, respectively. pNIA assay for nuclear import in yeast and bombardment of melon leaves with each of the NLSs fused to a 2xYFP reporter indicated that putative NLS1 and NLS2 were functional in transport of HsvG into the nucleus. A yeast two-hybrid assay showed that HsvB, HsvG, putative NLS1, putative NLS2, HsvG converted into HsvB, or HsvB converted into HsvG by exchanging the repeat domain, all interacted with AtKAP-α and importin-α3 of Arabidopsis thaliana. Deletion analysis of the NLS domains in HsvG suggested that putative NLS1 or NLS2 were required for pathogenicity on gypsophila cuttings and presumably for import of HsvG into the nucleus. This study demonstrates the presence of two functional NLSs in the type III effectors HsvG and HsvB.
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Affiliation(s)
- Dan M Weinthal
- Department of Molecular Biology and Ecology of Plants, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel.,Department of Plant Pathology and Weed Research, ARO, The Volcani Center, Bet Dagan 50250, Israel
| | - Isaac Barash
- Department of Molecular Biology and Ecology of Plants, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Tzvi Tzfira
- Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Victor Gaba
- Department of Plant Pathology and Weed Research, ARO, The Volcani Center, Bet Dagan 50250, Israel
| | - Doron Teper
- Department of Molecular Biology and Ecology of Plants, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Guido Sessa
- Department of Molecular Biology and Ecology of Plants, Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel
| | - Shulamit Manulis-Sasson
- Department of Plant Pathology and Weed Research, ARO, The Volcani Center, Bet Dagan 50250, Israel
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Stes E, Vandeputte OM, El Jaziri M, Holsters M, Vereecke D. A successful bacterial coup d'état: how Rhodococcus fascians redirects plant development. ANNUAL REVIEW OF PHYTOPATHOLOGY 2011; 49:69-86. [PMID: 21495844 DOI: 10.1146/annurev-phyto-072910-095217] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Rhodococcus fascians is a gram-positive phytopathogen that induces differentiated galls, known as leafy galls, on a wide variety of plants, employing virulence genes located on a linear plasmid. The pathogenic strategy consists of the production of a mixture of six synergistically acting cytokinins that overwhelm the plant's homeostatic mechanisms, ensuring the activation of a signaling cascade that targets the plant cell cycle and directs the newly formed cells to differentiate into shoot meristems. The shoots that are formed upon infection remain immature and never convert to source tissues resulting in the establishment of a nutrient sink that is a niche for the epiphytic and endophytic R. fascians subpopulations. Niche formation is accompanied by modifications of the transcriptome, metabolome, physiology, and morphology of both host and pathogen. Here, we review a decade of research and set the outlines of the molecular basis of the leafy gall syndrome.
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Affiliation(s)
- Elisabeth Stes
- Department of Plant Biotechnology and Genetics, Ghent University, 9052 Gent, Belgium.
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Abstract
Pantoea vagans is a Gram-negative enterobacterial plant epiphyte of a broad range of plants. Here we report the 4.89-Mb genome sequence of P. vagans strain C9-1 (formerly Pantoea agglomerans), which is commercially registered for biological control of fire blight, a disease of pear and apple trees caused by Erwinia amylovora.
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Diversity of the total bacterial community associated with Ghanaian and Brazilian cocoa bean fermentation samples as revealed by a 16 S rRNA gene clone library. Appl Microbiol Biotechnol 2010; 87:2281-92. [DOI: 10.1007/s00253-010-2698-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Revised: 05/25/2010] [Accepted: 05/25/2010] [Indexed: 11/27/2022]
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Aberrant synthesis of indole-3-acetic acid in Saccharomyces cerevisiae triggers morphogenic transition, a virulence trait of pathogenic fungi. Genetics 2010; 185:211-20. [PMID: 20233857 DOI: 10.1534/genetics.109.112854] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Many plant-associated microbes synthesize the auxin indole-3-acetic acid (IAA), and several IAA biosynthetic pathways have been identified in microbes and plants. Saccharomyces cerevisiae has previously been shown to respond to IAA by inducing pseudohyphal growth. We observed that IAA also induced hyphal growth in the human pathogen Candida albicans and thus may function as a secondary metabolite signal that regulates virulence traits such as hyphal transition in pathogenic fungi. Aldehyde dehydrogenase (Ald) is required for IAA synthesis from a tryptophan (Trp) precursor in Ustilago maydis. Mutant S. cerevisiae with deletions in two ALD genes are unable to convert radiolabeled Trp to IAA, yet produce IAA in the absence of exogenous Trp and at levels higher than wild type. These data suggest that yeast may have multiple pathways for IAA synthesis, one of which is not dependent on Trp.
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Tampakaki AP, Skandalis N, Gazi AD, Bastaki MN, Sarris PF, Charova SN, Kokkinidis M, Panopoulos NJ. Playing the "Harp": evolution of our understanding of hrp/hrc genes. ANNUAL REVIEW OF PHYTOPATHOLOGY 2010; 48:347-370. [PMID: 20455697 DOI: 10.1146/annurev-phyto-073009-114407] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
With the advent of recombinant DNA techniques, the field of molecular plant pathology witnessed dramatic shifts in the 1970s and 1980s. The new and conventional methodologies of bacterial molecular genetics put bacteria center stage. The discovery in the mid-1980s of the hrp/hrc gene cluster and the subsequent demonstration that it encodes a type III secretion system (T3SS) common to Gram negative bacterial phytopathogens, animal pathogens, and plant symbionts was a landmark in molecular plant pathology. Today, T3SS has earned a central role in our understanding of many fundamental aspects of bacterium-plant interactions and has contributed the important concept of interkingdom transfer of effector proteins determining race-cultivar specificity in plant-bacterium pathosystems. Recent developments in genomics, proteomics, and structural biology enable detailed and comprehensive insights into the functional architecture, evolutionary origin, and distribution of T3SS among bacterial pathogens and support current research efforts to discover novel antivirulence drugs.
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Chagué V, Maor R, Sharon A. CgOpt1, a putative oligopeptide transporter from Colletotrichum gloeosporioides that is involved in responses to auxin and pathogenicity. BMC Microbiol 2009; 9:173. [PMID: 19698103 PMCID: PMC2769210 DOI: 10.1186/1471-2180-9-173] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Accepted: 08/21/2009] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The fungus Colletotrichum gloeosporioides f. sp. aeschynomene produces high levels of indole-3-acetic acid (IAA) in axenic cultures and during plant infection. We generated a suppression subtractive hybridization library enriched for IAA-induced genes and identified a clone, which was highly expressed in IAA-containing medium. RESULTS The corresponding gene showed similarity to oligopeptide transporters of the OPT family and was therefore named CgOPT1. Expression of CgOPT1 in mycelia was low, and was enhanced by external application of IAA. cgopt1-silenced mutants produced less spores, had reduced pigmentation, and were less pathogenic to plants than the wild-type strain. IAA enhanced spore formation and caused changes in colony morphology in the wild-type strain, but had no effect on spore formation or colony morphology of the cgopt1-silenced mutants. CONCLUSION Our results show that IAA induces developmental changes in C. gloeosporioides. These changes are blocked in cgopt1-silenced mutants, suggesting that this protein is involved in regulation of fungal response to IAA. CgOPT1 is also necessary for full virulence, but it is unclear whether this phenotype is related to auxin.
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Affiliation(s)
- Véronique Chagué
- Department of Plant Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Rudy Maor
- Department of Plant Sciences, Tel Aviv University, Tel Aviv 69978, Israel
- Current address: Rosetta Genomics, 10 Plaut Street, Rehovot, 76706, Israel
| | - Amir Sharon
- Department of Plant Sciences, Tel Aviv University, Tel Aviv 69978, Israel
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