What Kind Of Cells Often Use The Malate-aspartate Shuttle?

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The malate-aspartate (M-A) shuttle provides an important mechanism to regulate glycolysis and lactate metabolism in the heart by transferring reducing equivalents from cytosol into mitochondria.

Why is malate Shuttle important for gluconeogenesis?

Since the malate-aspartate shuttle regenerates NADH inside the mitochondrial matrix, it is capable of maximizing the number of ATPs produced in glycolysis (3/NADH), ultimately resulting in a net gain of 38 ATP molecules per molecule of glucose metabolized.

What is the difference between malate-aspartate shuttle and glycerol phosphate shuttle?

Glycerol-3-phosphate shuttle generates 2 ATP for every cytosolic molecule oxidized, as FADH2 bypasses the first phosphorylation site in the electron transport chain. Malate aspartate shuttle generates 3 ATP for every cytosolic molecule oxidized. So, it is more efficient than the glycerol-3-phosphate shuttle.

Is the malate-aspartate shuttle reversible?

This shuttle is reversible, so electrons from NADH are brought into the mitochondrion when the NADH/NAD+ ratio is higher in the cytosol than in the mitochondrial matrix. The malate-aspartate shuttle yields approximately 3 molecules of ATP per molecule of cytosolic NADH and is found in liver, heart and kidney .

What kind of cells often use the glycerol phosphate shuttle?

In skeletal muscle cells, the NADH molecules produced in glycolysis must be transported onto the electron transport chain under aerobic conditions. To do this, these cells utilize a process called the glycerol 3-phosphate shuttle.

How many ATP can be produced from the complete oxidation of glucose if the malate aspartate shuttle is used?

The answer is e. 32.

Which of the following processes generates the most ATP?

Explanation: The electron transport chain generates the most ATP out of all three major phases of cellular respiration. Glycolysis produces a net of 2 ATP per molecule of glucose.

What organ does gluconeogenesis?

Gluconeogenesis, which occurs primarily in the liver, is the process by which glucose is generated. Most of the steps of glycolysis are reversible, and this is the primary means by which the liver will synthesize glucose.

How does the malate-aspartate shuttle enter the electron transport chain?

The malate–aspartate shuttle translocates electrons produced during glycolysis into mitochondria across the inner mitochondrial membrane.

What is malate in biology?

Malate is the ionized form (an ester or a salt) of malic acid. … The stereoisomeric form produced naturally is L-malate. It is involved in Krebs cycle. Krebs cycle (or citric acid cycle) is a series of redox reactions that occur in the mitochondrion to ultimately generate chemical energy that fuel metabolic reactions.

Can malate across the mitochondrial membrane?

On the cytoplasmic side a transaminase enzyme is used to remove an amino group from aspartate which is converted into oxaloacetate, then malate dehydrogenase enzyme uses an NADH cofactor to reduce oxaloacetate to malate which can be transported across the membrane because of the presence of a transporter.

How does malate-aspartate shuttle affect urea cycle?

The NADH is produced in two ways: … This malate is then oxidized to oxaloacetate by cytosolic malate dehydrogenase, generating a reduced NADH in the cytosol. Oxaloacetate is one of the keto acids preferred by transaminases, and so will be recycled to aspartate, maintaining the flow of nitrogen into the urea cycle.

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What is the purpose of the glycerol phosphate shuttle?

The glycerol-3-phosphate shuttle is a pathway that translocates electrons produced during glycolysis across the inner membrane of the mitochondrion for oxidative phosphorylation by oxidizing cytoplasmic NADH to NAD+.

Which electron carrier has a hydrophobic tail?

The ETC proteins in a general order are complex I, complex II, coenzyme Q, complex III, cytochrome C, and complex IV. Coenzyme Q, also known as ubiquinone (CoQ), is made up of quinone and a hydrophobic tail. Its purpose is to function as an electron carrier and transfer electrons to complex III.

Which type of respiration is the fastest?

Anaerobic respiration is a relatively fast reaction and produces 2 ATP, which is far fewer than aerobic respiration.

Which step of glucose metabolism yields the greater amount of ATP?

So, oxidative phosphorylation is the metabolic cycle that produces the most net ATP per glucose molecule.

What is the major route for ATP production?

In general, the main energy source for cellular metabolism is glucose, which is catabolized in the three subsequent processes—glycolysis, tricarboxylic acid cycle (TCA or Krebs cycle), and finally oxidative phosphorylation—to produce ATP.

How many ATP are produced by the glycerol P shuttle?

When cytosolic NADH transported by the glycerol 3-phosphate shuttle is oxidized by the respiratory chain, 1.5 rather than 2.5 ATP are formed.

How many molecules of ATP are formed by the oxidation of glucose?

Biology textbooks often state that 38 ATP molecules can be made per oxidized glucose molecule during cellular respiration (2 from glycolysis, 2 from the Krebs cycle, and about 34 from the electron transport system).

How many ATP does glucose produce?

One glucose molecule produces four ATP, two NADH, and two pyruvate molecules during glycolysis.

What type of bond is 1/3 Bisphosphoglycerate?

NADH formed must be reoxidized to regenerate NAD+ to sustain glycolysis. Energy released from this reaction is conserved as a high energy phosphate bond in 1,3-bisphosphoglycerate. Inorganic phosphate, rather than ATP, provides the source of the phosphoryl group.

What is NADH shuttle?

The NADH shuttle system, which transports the substrate for oxidative metabolism directly from the cytosol to the mitochondrial electron transport chain, has been shown to be essential for glucose-induced activation of mitochondrial metabolism and insulin secretion in adult β-cells.

What is glycerol-3-phosphate made from?

Glycerol 3-phosphate is produced from glycerol, the triose sugar backbone of triglycerides and glycerophospholipids, by the enzyme glycerol kinase. Glycerol 3-phospate may then be converted by dehydrogenation to dihydroxyacetone phosphate (DHAP) by the enzyme glycerol-3-phosphate dehydrogenase.

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