The isolation of wheat germ nuclei and some aspects of their glycolytic metabolism.

1. A procedure for isolating nuclei of the wheat germ in non-aqueous media has been described. 2. Such nuclei were shown to constitute about 50 per cent of the protoplasmic mass and to have a ribonucleic acid content of an order equivalent to that of the cytoplasm. 3. Studies of the distribution of the enzymes-aldolase, phosphoglyceraldehyde dehydrogenase, enolase, and pyruvate kinase-have revealed that the nuclei are the most vigorous sites of glycolytic activity. 4. Analysis of the DPN content of the nuclei in calf tissues-liver, pancreas, and heart-pointed to the probability that glycolytic activity is a characteristic common to many nuclei. 5. The significance of glycolytic activity to nuclear function has been discussed and some suggestive comparisons made between the two energy-yielding systems of glycolytic and oxidative phosphorylation.