since tiazofurin , selenazofurin , and their known metabolites failed to inhibit hypoxanthine-guanine-phosphoribosyl transferase , guanosine monophosphate kinase , and guanosine diphosphate kinase in cell extracts or permeabilized cells , these drugs may interfere with salvage transport across cellular membranes .
C0007634
cells
C0007603
cellular membranes