METABOLISM OF UNIFORMLY LABELLED MALTOSE-C14 INTRODUCED INTO DETACHED WHEAT AND TOBACCO LEAVES

Abstract

Uniformly labelled C¹⁴-starch was incubated in the presence of saliva yielding radioactive maltose, which was isolated by paper chromatography. When this maltose was introduced into detached tobacco and wheat leaves, it was found to be respired and transformed into other carbohydrates. There was no evidence to indicate that maltose is either a better starch former than glucose or that it acts as a specific glucose donor to fructose in the synthesis of sucrose. No dilution in the specific activity of maltose was observed even under the conditions of starch hydrolysis. This indicates that hydrolysis of starch in vivo does not result in the addition of maltose to the metabolic pool of cells.