Kynurenine as an Intermediate in the Formation of Nicotinic Acid from Tryptophane by Neurospora

Abstract
On the basis of the growth responses of mutant strains of Neurospora to tryptophane, nicotinic acid and kynurenine, nicotinic acid is assumed to be formed normally from tryptophane, with kynurenine as an intermediate. If this is correct, kynurenine has a biologic significance heretofore unsuspected. Whether kynurenine serves as an intermediate between tryptophane and nicotinic acid in the mammal remains to be detd.