Alicyclic acid metabolism in plants 7. Metabolism of 14G-labelled alicyclic acids in germinating Phaseolus mungo seeds

When Phaseolus mungo seeds were allowed to germinate in 5–20mM quinate solution in the dark, a marked increase in the endogenousshikimic acid level occurred in their tissues. The acid levelrose distincdy on the 2nd day of germination and reached a maximumon the 4th day. The quinate-¹⁴C fed to germinating seeds waspredominantly converted to shikimic acid, and little radioactivitywas found in 3-dehydroshikimic acid. When quinate-¹⁴C was suppliedsimultaneously with relatively high concentrations of 3-dehydroquinicacid or 3-dehydroshikimic acid, its conversionto shikimic acidwas restrained, but hardly any radioactivity was trapped ineither of the dehydro compounds. 3-Dehydroquinic acid-¹⁴C or3-dehydroshikimic acid-¹⁴C fed to the seeds was metabolizedpreferentially to shikimic acid. The experimental results arediscussed with respect to the metabolic relationship betweenquinic acid and odier alicyclic acids in the aromatic biosynthesisof P. mungo seedlings. (Received October 16, 1975; )