Chemical modification of carboxyl groups on spinach ferredoxin alters its ability to interact with ferredoxin:NADP reductase.
Treatment of spinach ferredoxin with glycine ethyl ester in the presence of a water soluble carbodiimide resulted in the modification of 3-4 carboxyl groups and decreased the ability of ferredoxin to participate in NADP photoreduction by chloroplast membranes by about 80%. The ability of the modified ferredoxin to receive electrons from the reducing side of Photosystem I was relatively unaffected. These findings suggest that the modified ferredoxin is unable to interact with ferredoxin:NADP reductase. This has been verified by demonstration that the modified ferredoxin fails to produce difference spectra typical of a ferredoxin-ferredoxin:NADP reductase complex when added to ferredoxin:NADP reductase.
D005287:Ferredoxin-NADP Reductase / Q000378:metabolism*; D005288:Ferredoxins; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism*; D010788:Photosynthesis; D010944:Plants / Q000201:enzymology; D013379:Substrate Specificity
D005288:Ferredoxins; D005287:Ferredoxin-NADP Reductase; D009247:NADH, NADPH Oxidoreductases