Inactivation of bacteriophage, DNA, and ribonuclease by thermal hydrogen atoms.
T1 phage, BU-T1 phage, infectious DNA extracted from phage phiX 174, and chromatographically purified ribonuclease were exposed to thermal hydrogen atoms, and the loss of plaque-forming ability, infectivity, or enzymatic activity was determined after various exposure times. Atomic hydrogen was generated by two different methods: (1) by a high-frequency discharge in hydrogen gas and (2) by irradiating a foil of polyethyleneter-ephthalate with 2-MeV protons. With increasing exposure time the surviving fraction of all objects tested approaches a constant level. After subtracting this constant "indestructible" fraction in either system, all objects were inactivated according to exponential curves. Furthermore, no BU sensitization was found to occur in BU-T1 phage exposed to atomic hydrogen, whereas gamma irradiation of samples from the same batches revealed a BU effect of a factor of 2.2. These experiments demonstrate hydrogen atoms to be efficient in causing biological damage. Consequently the terminology of "direct" and "indirect" radiation effect may have to be redefined.
Jung
H
H
Institut für Strahlenbiologie, Kernforschungszentrum Karlsruhe, Germany.
Kürzinger
K
K
D001435:Bacteriophages / Q000235:genetics* / Q000528:radiation effects*; D004279:DNA, Viral / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D006358:Hot Temperature; D006859:Hydrogen; D011829:Radiation Dosage; D012260:Ribonucleases / Q000737:chemistry* / Q000528:radiation effects*
D004279:DNA, Viral; D006859:Hydrogen; D012260:Ribonucleases