Corn Root Protoplasts: ISOLATION AND GENERAL CHARACTERIZATION OF ION TRANSPORT .

A method was developed for the large scale and rapid isolation of intact viable corn root protoplasts. Pure and metabolically active protoplasts were collected using a flotation technique. Vital staining tests, light and electron microscopy, and measurements of basic metabolic processes indicated that the isolated protoplasts were metabolically active, and that the plasmalemma and other organelles were well preserved. The isolated protoplasts performed normal, active ion transport functions. Time course of K(+) and inorganic phosphate (H(2)PO(4) (-)) influx and the effects of external pH, carbonyl cyanide p-trifluoromethoxyphenylhydrazone, fusicoccin, and diethylstilbestrol on K(+) and inorganic phosphate influx and net H(+) efflux in isolated protoplasts correlated well with data obtained on root segments. Data presented indicated that isolated protoplasts from roots can be used to gain additional insights into the mechanism of ion transport in plant cells.