RT Journal Article SR Electronic T1 Purine Nucleoside Phosphorylase from Human Erythrocytes III. Inhibition by the Inosine Analog Formycin B of the Isolated Enzyme and of Nucleoside Metabolism in Intact Erythrocytes and Sarcoma 180 Cells JF Molecular Pharmacology JO Mol Pharmacol FD American Society for Pharmacology and Experimental Therapeutics SP 293 OP 299 VO 4 IS 3 A1 M. R. SHEEN A1 BYUNG KYU KIM A1 R. E. PARKS, JR. YR 1968 UL http://molpharm.aspetjournals.org/content/4/3/293.abstract AB Formycin B, an analog of inosine, is a potent competitive inhibitor of purified erythrocytic purine nucleoside phosphorylase. The inhibition constant, Ki (1 x 10-4 M) is of the same order of magnitude as the Km for inosine (5 x 10-5 M). Formycin B also inhibits the degradation of nucleosides by intact and hemolyzed human erythrocytes and by Sarcoma 180 ascites cells. ACKNOWLEDGMENT The authors would like to express their appreciation to Dr. Sungnan Cha for his help in the preparation of this manuscript.