Set 7 Aa Cat

Front 1

How much ATP is produced during oxidative DeAmination? What enzyme catalyzes this reaction, and what is produced?

Back 1

2.5 ATP, in the form of NADH. Glutamate Dehydrogenase. Also, Ammonia and A-KG are produced

Front 2

How many ATP equivalents are used during the first (preliminary Step of the Urea Cycle, the step catalyed by Carbamoyl Phospahte Synthetase 1)

Back 2

2 ATP equivs.

Front 3

When Aspartate is not abundant, and it needs to be made for the Urea cycle, where does the Aspartate aminotransferase reaction take place?

Back 3

In the MT matrix.

Front 4

Where does Aspartate react for the Argininosuccinate synthetase reaction?

Back 4

In the cytosol

Front 5

Where is ATP invested to get Glutamate from a non Hepatic cell, to a liver cell, and it's Nitrogen groups removed and turned into UREA.

Where does Energy Come out of this process? What is the net ATP Gain? (not including breaking down the Carbon backbone of Glutamate.

Back 5

-1 ATP equiv. used to turn Glu-->Gln (glutamine synthetase)

+2.5 ATP gained from removing NH4+ from Glutamate.

-4 ATP are used to get both NH4+ groups onto HCO3 to form Carbamoyl Phosphate

-4 ATP are used in the Argininosuccinate synthetase reaction

+5 ATP are produced from producing Fumarate

-1.5 ATP Total

Front 6

Which Enzyme converts Glutamine --> Glutamate + NH4+? How much ATP is produced?

Back 6

Glutaminase. No ATP Equivalents are produced.

Front 7

What are the two types of regulation of the UREA cycle, and which is short term, and which is long term?

Back 7

Transcriptional regulation: Long term: changes amount of UREA cycle enzymes produced. More protein ingested, or extreme starvation increases the production of urea cycle enzymes

Allosteric Regulation: Short term.

Front 8

How does Allosteric regulation work in the Urea Cycle

Back 8

Arginine positively regulates N-Acetly Glutamate Synthase, which produces N-Acetyl Glutamate.

N-Acetyl Glutamate then can act as a positive regulator for CPS1.

This makes sense, as increased levels of Arginine and Glutamate help push the urea cycle along.

Front 9

Deficiency in Urea cycle enzymes are generally lethal at birth unless treated immediately.The lack of urea cycle enzymes leads to ___________. What are the symptoms? symptoms at birth?

Back 9

hyperammonemia (increased amounts of ammonia in the blood). Lethargy, brain damage, brain edema, Coma. At birth: Hypothermia, seizures, normal appearance, irritability and vomiting.

Front 10

What is the list of intermediates in the urea Cycle, beginning with Carbamoyl Phosphate + ornithine

Back 10

Citrulline --> Citrulyll -AMP Intermediate --> Arginino Succinase ---> Fumarate + Arginine --> Ornithine

Front 11

All of the Urea Cycle reactions are (reversible/Irreversible) except for the reaction catalyzed by ________

Back 11

Irreversible, ArgininoSuccinase. Produces Arginine + Fumarate.

Front 12

What Enzyme catalyzes the formation of Ornithine from Arginine?

Back 12

Arginase

Front 13

Where is ATP invested in the UREA cycle?

Back 13

the CPS1 rxn (2 ATP equips) and the Argininosuccinate synthetase rxn (2 ATP equips)

Front 14

What does ALT and AST stand for, and what are they markers for?

Back 14

Alanine transaminase (amino transferase), and Aspartate aminotransferase, respectively. Increased levels of these enzymes in the blood are indicative of Liver damage.

Front 15

What are some treatment options for patients with urea cycle deficiencies?

Back 15

the use of Nitrogen scavengers (to pick up N in the body and excrete it),

-Low protein Diet,

Liver transplant

-addition of Arginine (to stimulate the "roadblock" downstream of the mutation.

This is always patient specific though, these are just some general treatments.

Front 16

Which intermediates of the urea cycle can be excreted as non toxic products if there is a deficiency in one of the urea cycle enzymes?

Back 16

Citrulline and argininosuccinate.

Front 17

Why is Arginine supplementation good for some people with urea cycle deficiencies ? Which Deficiency cannot be treated with Arginine supplementation.

Back 17

Arginase Deficient patients won't benefit from Arginine supplementation. Arginine can be used to regenerate ornithine, to keep the cycle going, producing Citrulline or Arginino succinate (which can both be excreted to remove N from the cell, as they are non-toxic).

Front 18

Why is arginine an essential AA during times of positive Nitrogen balance?

Back 18

Protein syth > Protein Catabolism, therefor not much Arg is being created within the Urea Cycle, so it needs to be ingested.

Front 19

What is the acronym for the essential AAs, and what are they?

Back 19

PVT TIM HALL

Phenylalanine, Valine, Threonine, Tryptophan, isoleucine, methionine, Histidine, (Arginine), Leucine, Lysine

Front 20

How is Benzoate used to remove Nitrogen, and how does this decrease the amount of Ammonia within the body?

Back 20

Benzoate can acquire Nitrogen in the form of glycine, and they form a compound called hippurate (don't need to know). this molecule can be excreted from the body, removing Glycine. Because Gly concentration decreases, the body will have to use Free ammonia to produce more glycine.

Front 21

What is a prodrug, and give two examples WRT to Nitrogen scavengers?

Back 21

Inactive forms of a drug that can be activated by the bodies normal metabolic processes. Two examples are Benzoate and Phenylbutyrate.

Front 22

What happens to two of the 4 carbons on the butyrate group of phenyl butyrate once it enters the cell?

Back 22

they undergo Beta Oxidation, leaving PhenylAcetate (don't need to know name)

Front 23

Which AA does Phenylybutyrate remove from the body?

Back 23

Glutamine

Front 24

Which Nitrogen scavenger is more effective at decreasing the overall nitrogen level in the body and why?

Back 24

Phenylbutyrate. Glutamine has 2 Nitrogens, and Glycine only has 1.

Front 25

What do the Cori Cycle and the Alanine glucose cycle have in common?

Back 25

They both involve the transport of molecules between the liver and muscles.

Front 26

Why do Free FAs no provide enough E to muscle cells during periods of heavy activity?

Back 26

Not enough oxygen for Acetyl CoA to keep feeding into the krebs cycle (no krebs in anaerobic conditions), so the body must breakdown glucose in the blood and glycogen in the muscles.

Front 27

What happens to pyruvate in anaerobic conditions?

Back 27

It gets reduced to form Lactate by Lactate Dehydrogenase. This is essential to replenish the supply of NAD+ so Glycolysis can continue.

Front 28

What reaction does Pyruvate Dehydrogenase catalyze?

Back 28

Pyruvate + NAD+ + CoA-SH ---> Acetyl-CoA + NADH

creates E in the form of NADH (2.5 ATP) and Acetyl CoA is made.

Front 29

What constitutes the Cori Cycle?

Back 29

The cycling of lactate and Glucose between the muscles and the liver. During heavy activity, Glucose gets oxidized into Lactate. Lactate then travels to the liver, and gets converted to pyruvate ViA Lactate DHase. Pyruvate then gets converted into Glucose via Gluconeogenesis, and the glucose gets shipped back to the muscles though the blood from the liver.

Front 30

Explain the glucose-alanine cycle

Back 30

When there is heavy activity in muscle cells, some proteins are catabolized for Energy. the Nitrogenous waste products are gathered onto Glutamate. When [glutamate] is high, it can react with the pyruvate (which will also be in high concentrations), so to form Alpha-KG + Ala. Ala can then be transferred to the liver from the blood, and it can undergo the reverse reaction, to reform pyruvate. Pyruvate in the liver can then undergo gluconeogenesis to form glucose, which is then shipped back to the myocytes.