In the series of reactions comprising a metabolic sequence in cells or living organism, one central question has long concerned biochemists. Is a metabolite which is the product of one enzymic reaction and the substrate for a succeeding enzymic reaction formed and acted upon in a complex of the two proteins or is it produced in the first system and then dissociated into the surrounding medium to be captured and utilized by the second? This problem will be attacked in two ways: (a) by the use of dynamic light scattering to study the diffusional properties of the components of the system singly and together and by attempting to stabilize the presumptive complex of the two proteins through photochemical cross-linking. The two systems studied will be the glycerol phosphate dehydrogenase and lactate dehydrogenase two enzymes which have as a common metabolite, nicotinic-adenine-dinucleotide.
