Harpin, elicitor of the hypersensitive response produced by the plant pathogen Erwinia amylovora.

A proteinaceous elicitor of the plant defense reaction known as the hypersensitive response was isolated from Erwinia amylovora, the bacterium that causes fire blight of pear, apple, and other rosaceous plants. The elicitor, named harpin, is an acidic, heat-stable, cell-envelope-associated protein with an apparent molecular weight of 44 kilodaltons. Harpin caused tobacco leaf lamina to collapse and caused an increase in the pH of bathing solutions of suspension-cultured tobacco cells. The gene encoding harpin (hrpN) was located in the 40-kilobase hrp gene cluster of E. amylovora, sequenced, and mutated with Tn5tac1. The hrpN mutants were not pathogenic to pear, did not elicit the hypersensitive response, and did not produce harpin.

[1]  J. Way,et al.  New Tn10 derivatives for transposon mutagenesis and for construction of lacZ operon fusions by transposition. , 1984, Gene.

[2]  C. Baker,et al.  Concurrent loss in Tn5 mutants of Pseudomonas syringae pv. syringae of the ability to induce the hypersensitive response and host plasma membrane K+/H+ exchange in tobacco , 1987 .

[3]  D. Berg,et al.  Tn5tac1, a derivative of transposon Tn5 that generates conditional mutations. , 1988, Proceedings of the National Academy of Sciences of the United States of America.

[4]  J. M. Dodd,et al.  Thyroid Gland and Temperature Tolerance Relationships in Cold-blooded Vertebrates , 1963, Nature.

[5]  B. Staskawicz,et al.  Bacterial blight of soybean: regulation of a pathogen gene determining host cultivar specificity. , 1989, Science.

[6]  D. Lipman,et al.  Improved tools for biological sequence comparison. , 1988, Proceedings of the National Academy of Sciences of the United States of America.

[7]  Z. Klement.  Rapid Detection of the Pathogenicity of Phytopathogenic Pseudomonads , 1963, Nature.

[8]  J. Turner.  The Quantitative Relation Between Plant and Bacterial Cells Involved in the Hypersensitive Reaction , 1974 .

[9]  The Hypersensitive Reaction of Tobacco to Pseudomonas syringae pv. pisi: Activation of a Plasmalemma K/H Exchange Mechanism. , 1985, Plant physiology.

[10]  C. Richardson,et al.  A bacteriophage T7 RNA polymerase/promoter system for controlled exclusive expression of specific genes. , 1985, Proceedings of the National Academy of Sciences of the United States of America.

[11]  J. Beckwith,et al.  A genetic approach to analyzing membrane protein topology. , 1986, Science.

[12]  A. Osbourn,et al.  Molecular Genetics of Pathogenicity in Phytopathogenic Bacteria , 1988 .

[13]  S. Beer,et al.  Expression of Erwinia amylovora hrp genes in response to environmental stimuli , 1992, Journal of bacteriology.

[14]  C. Baker,et al.  Molecular cloning of a Pseudomonas syringae pv. syringae gene cluster that enables Pseudomonas fluorescens to elicit the hypersensitive response in tobacco plants , 1988, Journal of bacteriology.