title: Comparative analyses of exoproteinases produced by three phytopathogenic microorganisms.
abstract: Proteinases secreted by the oomycete Phytophthora infestans (Mont.) de Bary, Rhizoctonia solani, and Fusarium culmorum belonging to different families of fungi have been studied to determine if the exoenzyme secretion depends on the environmental conditions and the phylogenetic position of the pathogen. The substrate specificity of the extracellular proteinases of F. culmorum, R. solani, and P. infestans and their sensitivity to the action of synthetic and protein inhibitors suggest that they contain trypsin-like and subtilisin-like enzymes regardless of culture medium composition. The relation of trypsin-like and subtilisin-like enzymes is dependent on the culture medium composition, especially on the form of nitrogen nutrition, particularly in the case of the exoenzymes secreted by R. solani. Phylogenetic analyses have shown that the exoproteinase set of ascomycetes and oomycetes has more similarities than basidiomycetes although they are more distant relatives. Our data suggests that the multiple proteinases secreted by pathogenic fungi could play different roles in pathogenesis, increasing the adaptability and host range, or could have different functions in survival in various ecological habitats outside the host.
authors.affiliation: A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky Prospect 33-2, Moscow 119071, Russia.
authors.forename: Tatiana A
authors.initials: TA
authors.lastname: Valueva
authors.forename: Natalia N
authors.initials: NN
authors.lastname: Kudryavtseva
authors.forename: Alexis V
authors.initials: AV
authors.lastname: Sof'in
authors.forename: Tatiana A
authors.initials: TA
authors.lastname: Revina
authors.forename: Ekaterina L
authors.initials: EL
authors.lastname: Gvozdeva
authors.forename: Elena V
authors.initials: EV
authors.lastname: Ievleva