Light modulation of glucose-6-phosphate dehydrogenase: partial characterization of the light inactivation system and its effects on the properties of the chloroplastic and cytoplasmic forms of the enzyme.
Light inactivation of glucose-6-phosphate dehydrogenase within the pea (Pisum sativum L.) leaf chloroplast has a narrow pH optimum between 7.2 and 7.4 and is NADP-sensitive. The pH optimum for dark activation is slightly lower. Inactivation apparently results in a simple decrease in maximal velocity of the chloroplastic and cytoplasmic forms of the enzyme with no concomitant change in pH optimum or K(m) (glucose 6-phosphate).
Anderson
L E
LE
Department of Biological Sciences, University of Illinois at Chicago Circle, Chicago, Illinois 60680.
Duggan
J X
JX