MATERIALS AND METHODS A nonaqueous fractionation method to obtain highly purifled mesophyll chloroplasts from lyophilized leaves ofZea mays L. is described. The levels of several metabolites including pyruvate were determined in the purified mesophyll chloroplast fractions which were prepared from leaves exposed to different light intensities. The role of pyruvate in the regulation of pyruvate,...

The alterations of subcellular metabolite levels during the day in spinach leaves have been investigated using nonaqueous density gradient centrifugation to separate chloroplasts, cytosol, and vacuole. The results provide direct evidence for the role of sucrose phosphate synthase and cytosolic fructose 1,6-bisphosphatase in regulating sucrose synthesis in leaves and also show that the phosphate...

Fractionation of Amino Acids From Hydrolysates in Nonaqueous Systems: E. V. McCollum and Agatha A. Rider ............... 111 The Control of Grass Weeds in Sugar-Cane Fields in Puerto Rico: J. A. B Nolla ............. .......................... 112 Demonstration of Reducing Enzyme Systems in Neoplasms and Living Mammalian Tissues by Triphenyltetrazolium Chloride: Francis H. Straus, Nicholas D. C...

We show here how a Ru(bpy)2(CE-bpy) complex can be used for the ECL detection of sodium ion in both aqueous and nonaqueous media. Recognition of Na+ by the crown ether moiety in CE-bpy results in a significant increase in the ECL emission intensity of the complex.

Ir attempts to distinguish the various pools of metabolic products that may be chemically or physically separated in photosynthesizing cells, C14 labeled compounds have been fed to cells in a number of kinetic studies (2, 3, 7, 10). From these studies it is evident that the photosynthetic intermediates, presumably within the chloroplasts, rapidly acquire the same specific activity as the substr...