On the inhibition of tumor inception in the crown-gall disease with the use of ribonuclease A.

Abstract

The results reported in this study indicate that ribonuclease A, but not deoxyribonuclease, inhibited significantly the inception of tumors in the crown-gall disease of plants. Ribonuclease A did not affect the growth rate of the inciting bacteria either in culture or in a host. No differences could be observed, moreover, in the rate or extent of the wound-healing response when cells treated with ribonuclease A were compared with untreated cells in the region of a wound. These results suggest either that the tumor-inducing principle itself or an essential component of that principle is a ribonucleic acid, or that ribonuclease A enters the bacteria or the host cells and in either case selectively inactivates some component essential for tumor inception without, however, affecting the capacity of such cells to grow and divide at a rate comparable to that of untreated cells.