Association of NAD and NADP linked glyceraldehyde-3-phosphate dehydrogenase in the blue-green alga, Anabaena variabilis.

Gel-filtration of glyceraldehyde-3-phosphate dehydrogenase from Anabaena variabilis indicates a mol. wt. of 200,000-300,000, which is significantly greater than previously reported for this enzyme from other sources. Reaction rates in the presence NAD of and NADP suggest that one enzyme only is operative, being active with either coenzyme at any one time. Centrifugation and electrophoretic studies support this conclusion. The possible consequences of these results in the control of intermediary metabolism are discussed.