Fine Control of Purine Nucleotide Biosynthesis in Intact Cells of Catharanthus roseus

J Plant Physiol. 1984 Nov;116(5):417-23. doi: 10.1016/S0176-1617(84)80133-9. Epub 2012 Jan 20.

Abstract

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.