31P NMR studies of intact anchorage-dependent mouse embryo fibroblasts

31P NMR spectra of "normal" and x-ray-transformed anchorage-dependent mouse embryo fibroblasts (C3H/10T 1/2) at 145.7 MHz and 37 degrees C were obtained by using a solenoid coil probe with a sensitivity approximately 2.6 times higher than that of the standard Helmholtz coil probe. The cells were grown as monolayers on the surface of microcarrier beads. Results show that these cells have low levels of NMR-detectable ADP, are highly impermeable to protons, are capable of maintaining high ATP levels in the absence of respiration, and, when ATP generation is blocked, ultimately hydrolyze their existing ATP to a nonphosphorylated product and Pi. Only small differences were observed between the spectra of "normal" and transformed cells. However, the latter accumulated 2-deoxyglucose 6-phosphate at a faster rate.