The tryptophanase-tryptophan reaction

Abstract

EW-Phenylalanine and d[iota]-tyrosine bring about an increased storage of metabolizable polysaccharide in E. coli when the latter is grown on a medium of known composition containing tryptophan and glucose. The l( [long dash]) forms of these amino-acids are inactive in bringing about this increased polysaccharide storage. Mannose does not increase the polysaccharide storage of E. coli in the presence of dl-phenylalanine, and suggestions have been given to explain this. Tryptophan is antagonistic to dl-phenylalanine in its action on polysaccharide storage. Suggestions have been put forward to localize the site of activity of dl-phenylalanine, and also to relate the tryptophanase system and the systems concerned in carbohydrate breakdown.