Indole Acetic Acid Oxidase and Peroxidase Activities in Normal and Crown Gall Tissue Cultures of Parthenocissus Tricuspidata

Abstract

Lipetz, Jacques, and Arthur W. Galston. (Yale U., New Haven.) Indole acetic acid oxidase and peroxidase activities in normal and crown gall tissue cultures of Parthenocissus tricuspidata. Amer. Jour. Bot. 46(3) : 193‐196. Illus. 1959.—Normal and crown gall cells of P. tricuspidata grown in pure culture were examined for IAA oxidase and peroxidase activities. No IAA oxidase activity could be demonstrated in dialyzed or undialyzed homogenates of either tissue; however, crown gall tissue, but not normal tissue, was found to produce an extracellular IAA oxidase which required Mn++ and DCP as co‐factors. Normal tissue, but not crown gall tissue was found to contain high levels of substances which spared IAA from destruction by a pea IAA oxidase preparation. Peroxidase activity was found to be higher in normal than in crown gall homogenates, but crown gall tissue released considerably more peroxidase into the external medium. The differences in the auxin requirements and growth rate between normal and crown gall cells appear not to be easily explicable in terms of differential auxin destruction.

Auxin Oxidase and Growth Control in Tissue Cultures of Ephedra

“…As the tissues were routinely grown on a medium lacking exogenous IAA, it was possible that the enzyme was not induced. Therefore, sam- Lipetz and Galston (8) suggested that 1 of 2 or more components of the IAA oxidase system of Parthenocissus crown-gall tissue cultures is destroyed or inactivated when the tissue is homogenized. This observation is based upon the destruction of IAA by intact tissue in a reaction mixture containing Mn+ + and DCP, but lack of destruction by homogenates of the same tissue.…”

“…Despite the paucity of references attesting to the demonstration of IAA oxidase in plant tissue cultures (see, however, refs. 8,11,12,17), the simplest assumption to explain the behavior of the Ephedra tissue is that the tissue produces an IAA oxidase which destroys the IAA, but not the 2,4-D or NAA.…”

Ionic Effects on Lignification and Peroxidase in Tissue Cultures

“…DISCUSSION ENZYME LOSS FROM TISSUES: The release of enzymes and other substances from plant tissue cultures has been extensively documented. Among the enzymes released from these tissues are amylase (22), acid phosphatase (23), indole acetic acid oxidase (24) and peroxidase (25). Although variations in the magnitude of such losses exist, it is fairly well agreed that tissue cultures derived from plants or animals are "leaky.…”

Growth of Parthenocissus tricuspidata tissue cultured on media containing aza analogues of indole-3-acetic acid & indole-3-propionic acid

“…This difference in the two types of tissue has been the object of investigation for the last 10 years, and the possibilities for speculation have been narrowed. Several investigators have ruled out the possibility that the crown gall grows without auxin altogether (3,4). Therefore, the only remaining possibilities are that the auxin is produced more rapidly in the crown gall, that it is destroyed less rapidly, or that the tumor has a much lower auxin requirement.…”