Requirements for extraction of polyribosomes from plant callus cultures.

A procedure was developed to isolate polyribosomes from plant cell cultures. Tobacco callus extracted in 10 mm MgCl(2), 80 mm KCl, 250 mm sucrose, and 140 mm tris-HCl (pH 8.2) yielded larger amounts of polysomes than cells extracted in higher or lower ionic strength or pH buffers. Optimal conditions for extraction of polysomes from soybean callus were identical except the most suitable pH for recovery was 8.5. Addition of the divalent cation chelator, ethylene glycol-bis(2-aminoethyl ether)-tetraacetic acid (EGTA) to the extraction medium improved polysomal yield from tobacco and soybean cultures. Polysomes were successfully extracted from potato, tomato, corn, and barley cell cultures in extraction medium supplemented with EGTA.