scholarly journals Activation of NADP-Malate Dehydrogenase, Pyruvate,Pi Dikinase, and Fructose 1,6-Bisphosphatase in Relation to Photosynthetic Rate in Maize

1984 ◽  
Vol 76 (1) ◽  
pp. 238-243 ◽  
Author(s):  
Hideaki Usuda ◽  
Maurice S. B. Ku ◽  
Gerald E. Edwards
Keyword(s):  
Malate Dehydrogenase ◽  
Photosynthetic Rate ◽  
Fructose 1,6 Bisphosphatase

scholarly journals Glucose-induced inactivation of mitochondrial enzymes in the yeast Saccharomyces cerevisiae

1981 ◽  
Vol 198 (2) ◽  
pp. 281-287 ◽  
Author(s):  
M Takeda
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Malate Dehydrogenase ◽  
Mitochondrial Enzymes ◽  
Yeast Saccharomyces Cerevisiae ◽  
Cytoplasmic Proteins ◽  
Fructose 1,6 Bisphosphatase ◽  
Specific Activities

1. Addition of glucose induced an inactivation of mitochondrial enzymes in the yeast Saccharomyces cerevisiae containing normal mitochondrial particles. 2. The glucose-induced inactivation of mitochondrial enzymes was inhibited by the presence of cycloheximide. 3. Pepstatin also inhibited the inactivation, but phenylmethanesulphonyl fluoride accelerated the inactivation. 4. The specific activities of fructose 1,6-bisphosphatase and cytoplasmic malate dehydrogenase were decreased on the exposure to glucose, as well as those of the mitochondrial enzymes. However, the glucose-induced inactivation of cytoplasmic enzymes was not inhibited by the presence of pepstatin. 5. The specific activities of hexokinase and phosphofructokinase, which are cytoplasmic enzymes were increased by the addition of glucose, and this effect was not affected by pepstatin. 6. Addition of glucose resulted in an increase in the synthesis of proteins of the mitochondria and the cytosol, and simultaneously in degradation of these mitochondrial and cytoplasmic proteins.

Glyconeogenic and glycogenic enzymes in chronically active and normal skeletal muscle

1991 ◽  
Vol 71 (1) ◽  
pp. 182-191 ◽  
Author(s):  
R. J. Talmadge ◽  
H. Silverman
Keyword(s):  
Dehydrogenase Activity ◽  
Malate Dehydrogenase ◽  
Malic Enzyme ◽  
Glycogen Phosphorylase ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Glycogen Synthase ◽  
Glycogen Synthesis ◽  
Fructose 1,6 Bisphosphatase ◽  
Fast Twitch ◽  
Whole Muscle

The chronically active (pseudomyotonic) gastrocnemius muscle in the C57B16J dy2J/dy2J mouse contains both elevated lactate and glycogen as well as fibers that have high amounts of glycogen and enhanced glyconeogenic activity. In the present study we analyze the activities of some key glyconeogenic enzymes to assess the causes of elevated muscle glycogen and to determine the pathway for glycogen synthesis from lactate. Glycogen synthase, malate dehydrogenase, phosphoenolpyruvate carboxykinase, and malic enzyme were all elevated in homogenates of the chronically active muscle. Activities of glycogen phosphorylase and fructose 1,6-bisphosphatase were decreased in whole muscle homogenates. Histochemistry demonstrated that the high-glycogen fibers were typically fast-twitch glycolytic fibers that had high glycogen synthase, glycogen phosphorylase, and malic enzyme activities. Malate dehydrogenase activity followed succinate dehydrogenase activity and did not correlate to high-glycogen fibers. Thus the high-glycogen fibers have an elevated enzymatic capacity for glycogen synthesis from lactate, and the pathway may involve use of the pyruvate kinase bypass enzymes.

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