VIEW ARTICLE

Induction of Electrolyte Loss, Tissue Maceration, and Cellular Death of Potato Tissue by an Endopolygalacturonate Trans-Eliminase. M. S. Mount, Former Post Doctoral Research Associate, Department of Plant Pathology, Cornell University, Ithaca, New York 14850, Present address: Department of Plant Pathology, University of Massachusetts, Amherst 01002; D. F. Bateman(2), and H. Grant Basham(3). (2)(3)Professor, and Liberty Hyde Baily Research Assistant, respectively, Department of Plant Pathology, Cornell University, Ithaca, New York 14850. Phytopathology 60:924-931. Accepted for publication 1 December 1969. DOI: 10.1094/Phyto-60-924.

Extracts of Erwinia carotovora-infected potato tissues and filtrates of this pathogen cultured on nutrient broth supplemented with 0.1% sodium poly-pectate contained endopolygalacturonate trans-eliminase, proteinase, and phosphatidase C. These crude enzyme preparations contained a heat labile factor(s) that induced electrolyte loss, tissue maceration, and cellular death of potato tuber tissue discs. The endopolygalacturonate trans-eliminase was purified 295-fold from crude culture filtrate by ammonium sulfate fractionation, column chromatography on DEAE cellulose, and isoelectric focusing. The purified enzyme was free of proteinase, phosphatidase, and peroxidase activities, as well as enzymes which degrade araban, carboxymethyl cellulose, galactan, galactomannan, and xylan. This purified endopolygalacturonate trans-eliminase induced electrolyte loss, tissue maceration, and cellular death of potato tuber tissue. Electrolyte loss preceded maceration and cellular death. The results of this investigation suggest that a substrate for endopolygalacturonate trans-eliminase resides in the plant cell membrane or within the protoplast.