THE ACTIVATION OF METABOLIC SYSTEMS DURING CROWN-GALL TUMOR-CELL FORMATION

The Activation of Metabolic Systems during Crown-gall Tumor-cell Formation.

The transformation of normal plant tissue into tumor tissue occurs in three steps, which have been designated conditioning, induction, and promotion.' Conditioning is accomplished by substances present in the wound juice; induction by a tumorinducing principle (T-iP) produced by virulent Agrobacterium tumefaciens grown in unheated plant juice; and promotion, by indoleacetic acid or its physiolo...

Activation of Metabolic Systems During Tumor-Cell Formation.

Braunl-4 has clearly demonstrated that the transformation of normal plant cells into crown-gall tumor cells includes the progressive activation of enzyme systems which, once in operation, become a permanent part of the metabolic machinery of the altered cells. The work in our laboratory has paralleled that in Dr. Braun's with surprisingly similar results. We have, however, utilized a different ...

Recovery of crown-gall tumor cells.

nant animal cells are distinguished from healthy or inflaznmstory cells. In emphasizing the perma nency of the cellular alteration, Kidd (6) states that “Cancercells remain such until they die . . they never turn back en masse towards the benign or normal state. . . .“The inability to accomplish a reversal of malignant to normal cells under con trolled conditions has, however, served as a s...

The activation of two growth-substance systems accompanying the conversion of normal to tumor cells in crown gall.

Crown gall, a neoplastic disease of plants, is of interest because the inciting bacterium, Agrobacterium tumefaciens (Smith and Town.) Conn, converts normal plant cells to tumor cells in short periods of time. Once the cellular alteration has been accomplished, the continued abnormal proliferation of the affected host cells becomes completely independent of the inciting organism. These findings...

Tumor Formation by Attenuated Crown-Gall Bacteria in the Presence of Growth-Promoting Substances.