Enzymatic activity of actinomycetes from the genus Streptomyces isolated from the bulk soil and rhizosphere of the Pinus sylvestris

The enzymatic activity (chitinolytic, proteolytic, pectolytic andcellulolytic) of twenty strains of Streptomyces isolated from soil and rhizosphere of Scots pine was analyzed. Most strains produced chitinases, catalyzing the degradation of chitin, the main component of fungal cell walls including fungi pathogenic for plants. This activity was about 4 times higher in the presence of Fusariumoxysporum than Rhizoctonia solani mycelium or chitin flakes. The number of the proteolytic strains was also significant. In general, rhizosphere and soil organisms synthesizedcomparable amounts of these enzymes. Over half of the analyzed Streptomyces strains produced pectolytic enzymes (polygalacturonase, pectin lyase and pectate lyase). This property was more common among rhizosphere than among soil strains. The Streptomyces strains also showedcellulolytic activity (endocellulases, exocellulases) – enzymes decomposing basic components of cell walls of plant and lower fungi (cellulose). The cellulolytic activity was differentiated and depended on the Streptomyces strain. Conclusion of our studies is that Streptomyces are the microorganisms more chitinolytic andproteolytic than pectolytic and cellulolytic.