Envelope membranes from mature spinach chloroplasts contain a NADPH:protochlorophyllide reductase on the cytosolic side of the outer membrane.

摘要: Using fluorescence spectroscopy, we have demonstrated that isolated envelope membranes from mature spinach chloroplasts catalyze the phototransformation of endogenous protochlorophyllide into chlorophyllide in presence NADPH, but not NADH. Protochlorophyllide reductase was characterized further using monospecific antibodies (anti-protochlorophyllide reductase) raised against purified enzyme oat. In chloroplasts, is present only membranes. We reductase, a 37,000-dalton polypeptide, minor component and on outer surface membrane. This conclusion supported by several lines evidence: (a) polypeptide immunodecorated with anti-protochlorophyllide can be distinguished major E37 (which identified antibodies) after two-dimensional polyacrylamide gel electrophoresis; (b) hydrolyzed when intact were incubated thermolysin; (c) strongly agglutinate reductase. These results demonstrate differences exist between etioplasts respect to levels localization. The chloroplast membrane both substrate (protochlorophyllide) (protochlorophyllide necessary for synthesis could implications understanding chlorophyll biosynthesis chloroplasts.