Nicotinamide Adenine Dinucleotide as a Precursor of Nicotine in Nicotiana rustica L

Abstract

Quinolinic acid-2,3,7,8-14C, nicotinic acid-2,3,7-14C, and nicotinamide adenine dinucleotide-2,3,7-14C were shown to be incorporated into nicotine by Nicotiana rustica L. with very similar efficiencies. It is postulated that compounds of the pyridine nucleotide cycle, previously implicated as a source of metabolic intermediates for the biosynthesis of ricinine in Ricinus communis L., could serve the same function in nicotine biosynthesis in the tobacco plant.