* To whom correspondence should be addressed.
Received May 20, 2011; Revision received July 16, 2011
Influences on the acetylation degree of chitin manifested by proteins from cultural filtrates of strains of the fungus Septoria nodorum different in aggressiveness and of extracts from leaves of the susceptible (Triticum aestivum) and resistant (Triticum timopheevii) wheat plants infected with these strains were studied. Chitin deacetylase was found among the extracellular proteins of the fungus. Its activity was higher in the aggressive strain of the fungus than in the non-aggressive one, and this suggested that this enzyme could play an important role in the further formation of compatible relationship of the pathogens with the plants. Protein extracts from the susceptible wheat seedlings infected with the septoriosis agent also contained a component decreasing the acetylation degree of chitin. Protein extracts from the resistant wheat seedlings increased the chitin acetylation degree. It is supposed that this can be a pattern of the plant counteracting the action of chitin deacetylases of the pathogen.
KEY WORDS: wheat (Triticum aestivum, Triticum timopheevii), septoriosis agent (Septoria nodorum), chitin, chitosan, acetylation degree