[Activity of antioxidant system of Aspergillus versicolor with radioadaptive properties under conditions of exposure to radiation].

Melanin pigments were revealed for the first time in Aspergillus versicolor strains. Ionizing irradiation practically did not influence melanin synthesis in A. versicolor strains with radioadaptive properties and stimulated its synthesis in the control strain, which did not show such properties. High level of superoxide dismutase activity (from 100 up to 720 U/mg of protein) was revealed in the investigated strains. The irradiation in exponential phase of growth did not practically influence or raised activity of superoxide dismutase (SOD) in the strains with radioadaptive properties and oppressed its activity in the control strain. The irradiation in a stationary phase was accompanied by a decrease of SOD activity in the strains with radioadaptive properties, and essential (2 times) increase of SOD activity in the control strain and strain A. versicolor 101, which did not show radiotropism. The extracellular catalase activity (1.52-37.04 mmol x min(-1) x mg(-1) protein) exceeded by more than an order the intracellular one (8-230 mol x min(-1) x mg(-1) protein) in the investigated strains.