Adenine exogenously supplied to intact Catharanthus roseus cells was converted to adenine nucleotides. This treatment inhibited the incorporation of [(14)C]formate into total purines (purine bases, nucleosides, nucleotides and nucleic acids). Since the availability of phosphoribosylpyrophosphate (PRPP) appeared to exceed the requirement for de novo purine biosynthesis, its inhibition by exogenously supplied adenine was presumably due to an increase in adenine nucleotide concentration with resultant feedback inhibition rather than to depletion of PRPP.
Copyright © 1984 Gustav Fischer Verlag, Stuttgart. Published by Elsevier GmbH.. All rights reserved.