The Hungarian PUR (Phage and Uracil Response) project will be attached to the EXPOSE facility of the International Space Station ISS and is connected as a member to the ROSE (Response of Organisms on Space Environment) scientific consortium. The main goal of the PUR-project is to investigate and quantify the effect of specific space parameters (e.g. extraterrestrial solar radiation, non-oxidative environment) on nucleic acid models like bacteriophage T7 and uracil polycrystalls.

The research on solar UV effects on phage and uracil in polycrystalline form is very important for space experiments in the frame of the Hungarian PUR (Phage and Uracil Response) experiment of the EXPOSE facility on the International Space Station ISS and for exobiology related studies of future Mars missions like Mars Express/Beagle 2, Mars Netlander, etc. on the Martian surface. His theoretical and experimental studies on the photoreaction of nucleotides which show dimerization and the reverse process monomerization, implicate that biological harmful effects, can be reduced by shorter wavelength UV radiation, which reduces DNA damages injured by UV radiation in wavelength regions longer than 240 nm. This important result may help to understand how primitive microorganisms can survive on planetary surfaces which are not protected by an ozon layer, which was also the case on early Earth 2.5 - 3.8 Ga ago. A detailed knowledge of this of radiation damage reverse process could also answer the question if complex organic molecules and/or microorganisms could survive interplanetary transports on meteoroids.

More information on PUR can be found at the IWF report "Experiment verification tests for the PUR biological experiment on the EXPOSE facility of the International Space Station ISS".