Detection and Quantitation of Octopine in Normal Plant Tissue and in Crown Gall Tumors

Abstract

Octopine has been detected in normal tobacco leaf and stem tissue, normal sunflower stem tissue, pinto bean leaves, and normal tobacco callus tissue in culture. Octopine was identified in extracts by means of electrophoresis and chromatography in several solvent systems. Tobacco and sunflower tumor lines induced by various strains of Agrobacterium tumefaciens were found to contain from 1 to 240 times as much octopine as the normal plant tissues examined. Several strains of A. tumefaciens produce undifferentiated tobacco tumors containing high levels of octopine, but produce undifferentiated sunflower tumors containing normal levels of octopine and high levels of arginine. Further, strain CGIC of A. tumefaciens produces in tobacco an undifferentiated tumor which contains high levels of octopine and a teratoma which contains normal levels of octopine. This evidence shows that there is no consistent relationship between the causative strain of A. tumefaciens and the octopine content of the resulting crown gall tumor.