Specific 14C-labeling of isoprenoids of intact E. coli cells

Upon rehydration of lyophilized E. coli cells with phosphate buffer containing [14C]isopentenyl pyrophosphate, 14C was incorporated into the cells. Radioactivity was found in prenylquinones and some polyprenyl phosphate derivatives. Evidence was obtained suggesting that the latter compounds were interconverted to each other and that the "lipid cycle" operated in these cells.