[Main results of the Biorisk experiment on the International Space Station].

To get better appreciation of the margins of phenotypic adaptation and genotypic changes in bacteria-fungi associations within the typical microbiota residing on structural materials of space-flown equipment, developed were a program and hardware for a series of experiments under the general name BIORISK. Protocol of each experimental cycle is based on the well-proven method of exposure of "passive" samples of materials (Biorisk-KM), microorganisms-materials systems inside the ISS service module (Biorisk-MSV), and microorganisms-materials systems on the outside of the ISS SM (Biorisk-MSN). Each six months the samples are returned to the laboratory in conjunction with crew rotation. Already the first in-hand data from the experiment point to the dramatic effect of space flight on growth, reproduction, and biological properties of test microbes and fungi. Thus, the activity of enzymes that characterize the pathogenic potential (RNA-ase and DNA-ase), and resistance of microorganisms to aseptic agents were found increased.