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Evaluation of Escherichia coli cells damages induced by ultraviolet and proton beam radiation

Prokaryote cells were exposed to ultra violet (UVc) radiation and to proton beams in order for the induced effects to be studied. Morphological and physiological alterations occurred in Escherichia coli (E. coli) cells exposed to the beams were investigated. The measurements using UVc radiation were made at the Biology Department of CEFET-PR while the measurements using proton beams were made at the Pelletron Accelerator of the Physics of the University at São Paulo. An exposition time of 3 to 15 seconds for UVc radiation and dose ranging from 0.2 to 10.0 Gy for protons was used. A cellular survival curve versus exposition time and absorbed dose was built for each case. After the irradiation the cells were submitted to a series of biochemical tests. It was observed that the E.Coli cells lost some basic biochemical properties when the received doses were in the range of 0.2 to 0.7 Gy. By microscopic observations it was noticed that the E.Coli cells elongated after irradiation with UVc as well as with proton beam.


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