Table of Contents
How does citrate get out of mitochondria?
When the cell has excess energy, citrate is transported out of the mitochondrial matrix across the inner membrane via the mitochondrial citrate transport protein (CTP) (for review see ref.
What is the citrate transport system?
The mitochondrial citrate transport system, composed of citrate and malate transporters (MTs), can regulate the citrate efflux from mitochondria to cytosol, and then citrate is cleaved into OAA and acetyl-CoA which can be used for fatty acid (FA) biosynthesis.
What type of inhibitor is citrate?
One of these allosteric ligands is citrate, which acts as a potent allosteric inhibitor of the eukaryotic PFK enzymes.
What type of inhibition is citrate?
Citrate inhibits the reaction and is an example of product inhibition. The inhibition of citrate synthase by acetyl-CoA analogues has also been well documented and has been used to prove the existence of a single active site.
Why is citrate an inhibitor of glycolysis?
Citrate itself is known to inhibit several key glycolytic enzymes as part of a negative feedback loop. Phosphofructokinase (PFK) 1 and 2 are directly inhibited by citrate while pyruvate kinase (PK) is indirectly inhibited as citrate decreases levels of fructose-1,6-bisphosphate, which is a PK activator (42).
Why is citrate synthase important?
Citrate synthase is an enzyme active in all examined cells, where it is most often responsible for catalyzing the first reaction of the citric acid cycle (Krebs Cycle or the tricarboxylic acid [TCA] cycle): the condensation of acetyl-CoA and oxaloacetate to form citrate.
What is citrate synthase function?
What is citrate glycolysis?
Citrate. Citrate, the first product of the citric acid cycle, can also inhibit PFK. If citrate builds up, this is a sign that glycolysis can slow down, because the citric acid cycle is backed up and doesn’t need more fuel.
Why does citrate synthase inhibit acetyl-CoA?
Citrate synthase is responsible for the rate of reaction in the first step of the cycle when the acetyl-CoA is combined with oxaloacetic acid to form citrate. It is inhibited by high concentrations of ATP, acetyl-CoA, and NADH which indicates an already high level of energy supply.
What are the two main types of inhibitors?
There are two types of inhibitors; competitive and noncompetitive inhibitors.
What are 3 types of inhibitors?
There are three kinds of reversible inhibitors: competitive, noncompetitive/mixed, and uncompetitive inhibitors. Competitive inhibitors, as the name suggests, compete with substrates to bind to the enzyme at the same time. The inhibitor has an affinity for the active site of an enzyme where the substrate also binds to.