ACTINOMYCETES OF THE GENUS GEODERMATOPHILUS IN DESERT BIOGEOCENOSES

Actinomycetes with a specific complex life cycle were isolated from pl ant debris and soil samples collected in the Kyzyl Kum desert. The cul tures were assigned to the genus Geodermatophilus according to their m orphological and chemotaxonomic characteristics. New data on the ecolo gy of the organisms of this poorly-investigated genus was obtained. Ge odermatophiles account for a significant fraction of bacteria which co mprise a destructive link in desert ecosystems; their concentration is maximum in debris of typical desert plants. The ecological significan ce of the two forms characteristic of the life cycle of geodermatophil es is discussed in connection with the extreme habitat conditions. An analog has been found among eukaryotic microorganisms - yeasts of the genus Sarcinosporon, which have two life forms similar to those in pro karyotic geodermatophiles. The taxonomic status of the examined strain s of actinomycetes and species structure of the genus Geodermatophilus are discussed.