Citric Acid Cycle Regulation - Biochemistry
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In which of the following cases would the citric acid cycle be downregulated?
In which of the following cases would the citric acid cycle be downregulated?
The purpose of the citric acid cycle is to produce energy (both directly via GTP, and indirectly via NADH and 
. As such, energy can be though of to be on the products side of the sum of the reactions of the Krebs cycle. From Le Chatelier's principle, we know that if we want to inhibit a forward reaction, we can increase the concentration of the products. This will inhibit the forward reaction, and push the equilibrium to the left. Thus, in a high energy state, the ratio of ATP:ADP, like that of NADH:
is high since both ATP and NADH are products of metabolism.
The purpose of the citric acid cycle is to produce energy (both directly via GTP, and indirectly via NADH and
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Why can't acetyl-CoA produced from beta-oxidation enter into the Krebs Cycle without carbohydrates present?
Why can't acetyl-CoA produced from beta-oxidation enter into the Krebs Cycle without carbohydrates present?
The entry point for acetyl CoA in the Krebs cycle is oxaloacetate. Acetyl-CoA and oxaloacetate combine to form citrate, which then continues through the cycle. Oxaloacetate is a carbohydrate, and so without carbs the acetyl-CoA can not enter into the Krebs cycle.
The entry point for acetyl CoA in the Krebs cycle is oxaloacetate. Acetyl-CoA and oxaloacetate combine to form citrate, which then continues through the cycle. Oxaloacetate is a carbohydrate, and so without carbs the acetyl-CoA can not enter into the Krebs cycle.
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Which of the following is not a regulated step of the citric acid cycle?
Which of the following is not a regulated step of the citric acid cycle?
The regulated steps of the citric acid cycle are citrate synthase, isocitrate dehydrogenase, and alpha-ketoglutarate dehydrogenase. These steps are inhibited and stimulated by various products and reactants within the citric acid cycle. Succinate dehydrogenase is not regulated by products or reactants, and is therefore not rate limiting.
The regulated steps of the citric acid cycle are citrate synthase, isocitrate dehydrogenase, and alpha-ketoglutarate dehydrogenase. These steps are inhibited and stimulated by various products and reactants within the citric acid cycle. Succinate dehydrogenase is not regulated by products or reactants, and is therefore not rate limiting.
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