Open AccessProtein(s) from the Gram-Positive Bacterium Clavibacter michiganensis subsp. michiganensis Induces a Hypersensitive Response in Plants
Author(s) -
Claudia Fernández Alarcón,
Joana Castro,
Fernando L. García-Gil de Muñoz,
Patricio Arce–Johnson,
Jorge Torres Delgado
Publication year - 1998
Publication title -
phytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.264
H-Index - 131
eISSN - 1943-7684
pISSN - 0031-949X
DOI - 10.1094/phyto.1998.88.4.306
Subject(s) - clavibacter michiganensis , biology , microbiology and biotechnology , nicotiana tabacum , bacteria , gel electrophoresis , hypersensitive response , polyacrylamide gel electrophoresis , proteases , pathogen , biochemistry , programmed cell death , enzyme , apoptosis , genetics , gene
The gram-positive tomato pathogen Clavibacter michiganensis subsp. michiganensis induced a local necrotic response on four-o'clock (Mirabilis jalapa) and tobacco (Nicotiana tabacum) plants. This necrosis response was characteristic of the hypersensitive response (HR). The cell-free culture supernatant from strain CMM623 also induced a necrosis that was phenotypically similar to that induced by the bacteria. Inhibitors of plant metabolism suppressed the necrotic reaction of both M. jalapa and tobacco. The HR-inducing activity present in the supernatant was heat stable, sensitive to proteases, and had an apparent molecular mass in the range of 35 to 50 kDa as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The properties observed for the necrosis-inducing activity resembled harpin and PopA described from gram-negative phytopathogenic bacteria.