Chloroplast class I and class II aldolases are bifunctional for fructose-1,6-biphosphate and sedoheptulose-1,7-biphosphate cleavage in the Calvin cycle
A. Flechner et al., Chloroplast class I and class II aldolases are bifunctional for fructose-1,6-biphosphate and sedoheptulose-1,7-biphosphate cleavage in the Calvin cycle, FEBS LETTER, 447(2-3), 1999, pp. 200-202
Class I and class LI aldolases are products of two evolutionary non-related
gene families. The cytosol and chloroplast enzymes of higher plants are of
the class I type, the latter being bifunctional for fructose-1,6- and sedo
heptulose-l,7-P-2 in the Calvin cycle. Recently, class II aldolases were de
tected for the cytosol and chloroplasts of the lower alga Cyanophora parado
xa. The respective chloroplast enzyme has been shown here to be also bifunc
tional for fructose-1,6- and sedoheptulose-1,7-P-2. Kinetics, also includin
g fructose-1-P, were determined for all these enzymes. Apparently, aldolase
s are multifunctional enzymes, irrespective of their class I or class II ty
pe. (C) 1999 Federation of European Biochemical Societies.