ICOM1 Abstract

DENISOVA, NINA. V.L.Komarov Botanical Institute of Russian Academy of Sciences, prof. Popov str. 2, St.Petersburg, 197376, Russia. - Can we account the proteolytic peculiarity of ectomycorrhizal basidiomycetes as an adequate characteristic of their ecological feature? The correlation between the level of proteolytic activity (especially fibrinolytic, FA, and trombolytic, TA) and ecological belonging of ectomycorrhizal basidiomycetes was revealed on the base of extensive experimental researches of basidiomycete cultures (more than 700 strains from the Botanical Institute Collection) and fruit bodies (about 400 species). The most strongly pronounced synthesis of the proteinases with FA is typical for saprotrophic basidiomycetes (especially for species connected to utilisation of ligno-cellulose complexes). We propose that proteinases with FA and TA can take part in the ecologo-trophic function for such mushrooms. The macromycetes with symbiotrophic (or parasitic) type of life have not marked level of these enzymes activity. Some species which traditionally were considered as the obligate symbiotrophs were the exception from the rule and had high FA and TA levels. There were, for example, some species from genera Tricholoma, Boletus, Russula, Lactarius. We think that there examples could provide evidence of the ability of some strictly mycorrhizal species to switch from obligate into facultative type of symbiotrophism. Apparently, symbiotrophs dwelling in well-being forests do not need to have a high level of proteolytic activity. However it can not be excluded that symbiotrops can have pronounced biosynthesis of mentioned proteinases as an additional mechanism of regulation of ecologo-trophic functioning in the ecosystems where symbioticrelations between myco- and phitobionts are broken. It is possible that the obligate character of symbiotic relations for some species of macromycetes should be corrected.