Alicyclic acid metabolism in plants V. Biosynthesis of alicyclic acids from 14C-labeled glucose and erythrose in some plant tissues

Etiolated seedlings of Phaseolus mungo were fed with ¹⁴C-glucoseand the incorporation of ¹⁴C into shikimic and quinic acidswas determined. The incorporation of ¹⁴C into shikimic acidwas enhanced when non-labeled shikimic, quinic or 5-dehydroquinicacid was not significantly affected by these alicyclic acids.To examine whether the difference in biosynthetic patterns betweenshikimic and quinic acids is common in higher plants, flowersand leaves of several plants were fed with ¹⁴C-glucose or ¹⁴C-erythroseand the effciencies of these labeled sugars as precursors ofshikimic and quinic acids were compared. In seven of eight plantsamples, erythrose was superior to glucose as the precursorof shikimic acid, while there was no great difference in theefficiency of either sugar as the precursor of quinic acid.The possibility that the biosynthetic mechanism for quinic aciddiffers from that for shikimic acid is discussed. (Received September 12, 1973; )