Sauer, A.A.SauerBothe, H.H.BotheNeuer, G.G.NeuerPapen, H.H.Papen2022-03-022022-03-021986https://publica.fraunhofer.de/handle/publica/173934Glyceraldehyde-3-P dehydrogenase (GAPDH) in heterocysts and vegetative cells of 3 N2-fixing cyanobacteria was found to utilize both NAD(+)-ion and NADP(+)-ion. The enzyme activity was enhanced by thiols (glutathione, reduced lipoic acid and dithiothreitol). GADPDH of the 3 cyanobacterial species was not activated by thioredoxin. Heterocysts have now been shown to possess all the enzymes of glycolysis and the tricarboxylic acid cycle to convert glyderaldehyde-3-phosphate (GAP) to oxoglutarate and glutamate. The GADPDH reaction is a major source for the generation of NADH, which is oxidized by a thylakoidbound NADP:plastoquinone oxidoreductase in heterocysts. (IFU)en579journal article