INACTIVATION OF BACTERIOPHAGES BY DECAY OF INCORPORATED RADIOACTIVE PHOSPHORUS

Abstract

The inactivation of the bacteriophages T1, T2, T3, T5, T7 and lambda by decay of incorporated P32 was studied. A comparison of the rates of inactivation of these bacteriophages indicates that the fraction of all P32 disintegrations which are lethal (efficiency of killing) is nearly 0.1 at +4[degree]C for all the strains. This efficiency depends upon the temperature at which decay proceeds. T2 bacteriophages inactivated by decay of incorporated P32 do not exhibit multiplicity reactivation or photoreactivation. The results are consistent with the view that inactivation of a radioactive bacteriophage is caused by a short range consequence of the decay of one of its P32 atoms. The implications of the findings are discussed in terms of the double stranded structure of the deoxyribonucleic acid (DNA) molecule.