Nucleoside-dependent synthesis of organic phosphorus compounds by rat liver nuclei

a) A modified procedure of the WIDNELL and TATA8 method yields rat liver nuclei manifesting a high degree of purity and activity. b) These nuclei contain a nucleoside-dependent phosphorylating activity that is readily released and apparently unrelated to either glycolysis or respiration. c) The main incorporation of the 32Pi is into ribose-I-phosphate; nucleoside phosphorylase activity satisfactorily accounts for the observed purine nucleoside stimulation of the nuclear phosphorus metabolism.