Isoenzymes of pyruvate kinase in etioplasts and chloroplasts.
Reads0
Chats0
TLDR
Isoenzymes of pyruvate kinase from green leaves of castor bean and etiolated leaves of pea plants have been separated by ion filtration chromatography, finding the plastid enzyme has a much sharper optimum at pH 8, and is less efficient at using alternative nucleotides.Abstract:
Isoenzymes of pyruvate kinase from green leaves of castor bean and etiolated leaves of pea plants have been separated by ion filtration chromatography. One of the isoenzymes is localized in the plastid, whereas the other is in the cytosol. The cytosolic enzyme has a pH optimum from pH 7 to pH 9, and is able to utilize nucleotides other than ADP as the phosphoryl acceptor. The plastid enzyme has a much sharper optimum at pH 8, and is less efficient at using alternative nucleotides. The plastic pyruvate kinase, unlike the cytosolic enzyme, requires the presence of dithiothreitol or 2-mercaptoethanol during isolation and storage to stabilize the activity.read more
Citations
More filters
Journal ArticleDOI
Spatial Organization of Enzymes in Plant Metabolic Pathways
Geza Hrazdina,Roy A. Jensen +1 more
TL;DR: The role of Isozymes in Metabolic Compartmentation, Cellular Metabolism, and Organismic Organization in the DIVERSE PATHWAyS are studied.
Journal ArticleDOI
Methylerythritol 4-phosphate (MEP) pathway metabolic regulation
TL;DR: The role of the MEP pathway in photosynthetic leaves during isoprene emission and more generally the metabolic regulation of the UKIP pathway in both plants and bacteria are focused on.
Journal ArticleDOI
Enzymatic Evidence for a Complete Oxidative Pentose Phosphate Pathway in Chloroplasts and an Incomplete Pathway in the Cytosol of Spinach Leaves.
TL;DR: The data indicate that chloroplasts of spinach leaf cells possess the complete complement of enzymes of the oxidative pentose phosphate path-way (OPPP), whereas the cytosol contains only the first two reactions, contrary to the widely held view that plants generally possess a cytosolic OPPP capable of cyclic function.
Journal ArticleDOI
Molecular and immunological characterization of plastid and cytosolic pyruvate kinase isozymes from castor‐oil‐plant endosperm and leaf
TL;DR: Monospecific antiserum was raised in rabbits to homogeneous cytosolic pyruvate kinase isolated from 5-day-old germinating endosperm of the castor oil plant, Ricinus communis, and each polypeptide was characterized by amino acid composition analysis and peptide mapping by CNBr fragmentation, indicating sequence similarity between the twopolypeptides.
Journal ArticleDOI
Evolving concepts in plant glycolysis: two centuries of progress
TL;DR: The duplication of the glycolytic pathway in plants and the flexible nature of the pathway have possibly evolved in relation to the crucial biosynthetic role played by plant Glycolysis beyond its function in energy generation; both functions must proceed if a plant is to survive under varying and often stressful environmental or nutritional conditions.
References
More filters
Journal ArticleDOI
The role of pH in the regulation of carbon fixation in the chloroplast stroma. Studies on CO2 fixation in the light and dark.
TL;DR: It is shown that intact chloroplasts are able to fix CO2 in the dark, yielding 3-phosphoglycerate, and demonstrates that CO2 fixation in thedark is not possible, unless the pH in the medium is artificially raised to pH 8.8.
Journal ArticleDOI
Enzymes of the Glycolytic and Pentose Phosphate Pathways in Proplastids from the Developing Endosperm of Ricinus communis L.
TL;DR: The unique segregation of the two oxidative steps in the pentose phosphate pathway may be required to meet the metabolic needs of these fat-storing seeds.
Journal ArticleDOI
Studies on biosynthesis of waxes by developing jojoba seed tissue
TL;DR: Slices of developing jojoba cotyledons incorporated a variety of precursors in to wax, free alcohols, and polar lipids, suggesting the existence of metabolically separate pools of acetate and/or sites for de novo synthesis and elongation of acyl chains.
Journal ArticleDOI
Chloroplast Phosphofructokinase I. Proof of Phosphofructokinase Activity in Chloroplasts
Grahame J. Kelly,Erwin Latzko +1 more
TL;DR: It was concluded that most leaves contain phosphofructokinase activity in chloroplasts as well as in the cytoplasm, and spinach chloroplast activity, which was at least 2.5 mumoles fructose 1,6-bisphosphate formed per mg chlorophyll per hour, did not result from contamination by cy toplasm or by other cellular organelles, and was not detected until after chloroplast were broken.
Related Papers (5)
Capacities of pea chloroplasts to catalyse the oxidative pentose phosphate pathway and glycolysis
Mark Stitt,Tom ap Rees +1 more