The role of tryptophan in the physiology of Neurospora.

The genetics and biochemistry of tryptophan metabolism in the bread mold, Neurospora cras&a, have received considerable experimental attention during the past 20 years. By now, an impressive body of information has accumulated to the extent that the intimate details of the biosynthesise and degradation'-' of tryptophan in Neurospora are well known and also to the extent that the genetics of this interesting series of reactions now serves as a textbook model to illustrate the relationship between genes and enzymes.7 These are subjects that have been reviewed extensively elsewhere."' In this review we shall concern ourselves with the physiological implications of the metabolism of tryptophan by Neurospora with particular regard to the regulatory mechanisms which impinge on this interesting system.