The C-Terminal Half of the HrpN Virulence Protein of the Fire Blight Pathogen Erwinia amylovora Is Essential for Its Secretion and for Its Virulence and Avirulence Activities
The HrpN (harpin) protein of the fire blight pathogen Erwinia amylovora is an essential virulence factor secreted via the bacterial type III secretion system. HrpN also has avirulence activity when delivered to tobacco by E. amylovora and has defense elicitor activity when applied to plants as a cel...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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The American Phytopathological Society
2008-11-01
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| Series: | Molecular Plant-Microbe Interactions |
| Subjects: | |
| Online Access: | https://apsjournals.apsnet.org/doi/10.1094/MPMI-21-11-1387 |
| _version_ | 1818647208913797120 |
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| author | Judith P. Sinn Chang-Sik Oh Philip J. Jensen Sara C. D. Carpenter Steven V. Beer Timothy W. McNellis |
| author_facet | Judith P. Sinn Chang-Sik Oh Philip J. Jensen Sara C. D. Carpenter Steven V. Beer Timothy W. McNellis |
| author_sort | Judith P. Sinn |
| collection | DOAJ |
| description | The HrpN (harpin) protein of the fire blight pathogen Erwinia amylovora is an essential virulence factor secreted via the bacterial type III secretion system. HrpN also has avirulence activity when delivered to tobacco by E. amylovora and has defense elicitor activity when applied to plants as a cell-free protein extract. Here, we characterize a series of random mutations in hrpN that altered the predicted amino acid sequence of the protein. Amino acid substitutions and deletions in the highly conserved, C-terminal portion of HrpN disrupted the virulence and avirulence activities of the protein. Several of these mutations produced a dominant-negative effect on E. amylovora avirulence on tobacco. None of the mutations clearly separated the virulence and avirulence activities of HrpN. Some C-terminal mutations abolished secretion of HrpN by E. amylovora. The results indicate that the C-terminal half of HrpN is essential for its secretion by E. amylovora, for its virulence activity on apple and pear, and for its avirulence activity on tobacco. In contrast, the C-terminal half of HrpN was not required for cell-free elicitor activity. This suggests that the N-terminal and C-terminal halves of HrpN mediate cell-free elicitor activity and avirulence activity, respectively. |
| first_indexed | 2024-12-17T00:58:53Z |
| format | Article |
| id | doaj.art-282f93149d7240d8bf34656c276b532b |
| institution | Directory Open Access Journal |
| issn | 0894-0282 1943-7706 |
| language | English |
| last_indexed | 2024-12-17T00:58:53Z |
| publishDate | 2008-11-01 |
| publisher | The American Phytopathological Society |
| record_format | Article |
| series | Molecular Plant-Microbe Interactions |
| spelling | doaj.art-282f93149d7240d8bf34656c276b532b2022-12-21T22:09:32ZengThe American Phytopathological SocietyMolecular Plant-Microbe Interactions0894-02821943-77062008-11-0121111387139710.1094/MPMI-21-11-1387The C-Terminal Half of the HrpN Virulence Protein of the Fire Blight Pathogen Erwinia amylovora Is Essential for Its Secretion and for Its Virulence and Avirulence ActivitiesJudith P. SinnChang-Sik OhPhilip J. JensenSara C. D. CarpenterSteven V. BeerTimothy W. McNellisThe HrpN (harpin) protein of the fire blight pathogen Erwinia amylovora is an essential virulence factor secreted via the bacterial type III secretion system. HrpN also has avirulence activity when delivered to tobacco by E. amylovora and has defense elicitor activity when applied to plants as a cell-free protein extract. Here, we characterize a series of random mutations in hrpN that altered the predicted amino acid sequence of the protein. Amino acid substitutions and deletions in the highly conserved, C-terminal portion of HrpN disrupted the virulence and avirulence activities of the protein. Several of these mutations produced a dominant-negative effect on E. amylovora avirulence on tobacco. None of the mutations clearly separated the virulence and avirulence activities of HrpN. Some C-terminal mutations abolished secretion of HrpN by E. amylovora. The results indicate that the C-terminal half of HrpN is essential for its secretion by E. amylovora, for its virulence activity on apple and pear, and for its avirulence activity on tobacco. In contrast, the C-terminal half of HrpN was not required for cell-free elicitor activity. This suggests that the N-terminal and C-terminal halves of HrpN mediate cell-free elicitor activity and avirulence activity, respectively.https://apsjournals.apsnet.org/doi/10.1094/MPMI-21-11-1387DspA/EHrpWHrpJhypersensitive response |
| spellingShingle | Judith P. Sinn Chang-Sik Oh Philip J. Jensen Sara C. D. Carpenter Steven V. Beer Timothy W. McNellis The C-Terminal Half of the HrpN Virulence Protein of the Fire Blight Pathogen Erwinia amylovora Is Essential for Its Secretion and for Its Virulence and Avirulence Activities Molecular Plant-Microbe Interactions DspA/E HrpW HrpJ hypersensitive response |
| title | The C-Terminal Half of the HrpN Virulence Protein of the Fire Blight Pathogen Erwinia amylovora Is Essential for Its Secretion and for Its Virulence and Avirulence Activities |
| title_full | The C-Terminal Half of the HrpN Virulence Protein of the Fire Blight Pathogen Erwinia amylovora Is Essential for Its Secretion and for Its Virulence and Avirulence Activities |
| title_fullStr | The C-Terminal Half of the HrpN Virulence Protein of the Fire Blight Pathogen Erwinia amylovora Is Essential for Its Secretion and for Its Virulence and Avirulence Activities |
| title_full_unstemmed | The C-Terminal Half of the HrpN Virulence Protein of the Fire Blight Pathogen Erwinia amylovora Is Essential for Its Secretion and for Its Virulence and Avirulence Activities |
| title_short | The C-Terminal Half of the HrpN Virulence Protein of the Fire Blight Pathogen Erwinia amylovora Is Essential for Its Secretion and for Its Virulence and Avirulence Activities |
| title_sort | c terminal half of the hrpn virulence protein of the fire blight pathogen erwinia amylovora is essential for its secretion and for its virulence and avirulence activities |
| topic | DspA/E HrpW HrpJ hypersensitive response |
| url | https://apsjournals.apsnet.org/doi/10.1094/MPMI-21-11-1387 |
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