Effect of x irradiation on amino acid utilization in cultured insect cells

Cultured Trichoplusia ni cells in exponential growth were administered x-ray doses of 10,000 R and then subcultured. The concentration of alanine increased greatly and ammonia increased slightly in media of both untreated and irradiated cells up to 96 hr. Glycine concentration did not change significantly while the concentration of the remaining amino acids decreased to varying extents in media from both irradiated and untreated cultures. It was assumed that a decreasing amino acid concentration in the growth medium was due to utilization of the amino acids by the cells while an increasing amino acid concentration reflected its production by the cells. In medium from both untreated and x-irradiated cultures, a decrease in glutamic acid concentration was proportional to an increase in alanine concentration. With time spent in culture, the amounts consumed and produced per cell were much higher in the irradiated cultures