Amino Acid Oxidation Flashcards Preview

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Flashcards in Amino Acid Oxidation Deck (37):
1

What can the 7 intermediates produced from the aa be subdivided into

1. Glucogenic: TCA cycle intermediates that can be shunted to gluconeogenesis
2. Ketogenic: AcetylCoA derivates that can be used for ketone body synthesis.

2

18/20 aa are at least partially______. 4/20 glucogenic and ketogenic products include ____2/20 are purely ketogenic.

glucogenic. 3 aromatics + Ile; Leu and Lys

3

Methionine breaks down into ____. Phenylalanine breaks down into ______

cysteine; tyrosine

4

The key to interconversion of aa & carbs lies in the interrelationship between aa and:

alpha keto acids

5

What are the 7 metabolites of aa metabolism in glucogenic and ketogenic

Glucogenic:
1. pyruvate
2. oxaloacetate
3. alpha KG
4. fumerate
5. propionylCoA

Ketogenic:
6. acetoacetyl CoA
7. acetylCoA

6

Which aa form into pyruvate

1. Alanine
2. Serine
3. Cysteine
4. Tryptophan

7

3C aa form a 3 C alpha keto acid to make

pyruvate

8

What are the 4C aa that are metabolized to make oxaloaceate

1. Asparagine
2. Aspartate

9

What are the 5C aa that are metabolized to make alpha keto Glutarate

1. Glutamine
2. Proline
3. Argenine
4. Histidine
5. Glutamate

10

Which branched chain aa make up succyinyl CoA and acetyl CoA

1. Ile
2. Valine
3. Leucine

11

Valine gets converted to propionyl CoA which means its strictly

glucogenic

12

Ile gets converted to propionylCoA + acetylCoA which means its both:

glucogenic and ketogenic

13

Leu gets converted to acetoacetate which means its strictly

ketogenic

14

Branched chain aa share the first steps of:

oxidation. Get transaminated via branched chain aminotransferase

15

Which aa make up succinylCoA

1. Methionine
2. Threonine

16

Breakdown of methionine produces:

cysteine

17

Met & Thr yield alpha keto butyrate that is converted to

propionylCoA.

18

PropionylCoA gets converted to:

succinylCoA

19

What does methlmalonyl CoA mutase need

cobalmin (B12)

20

What is munechausen syndrome by proxy

making people get purposefully sick to get attention

21

What are the two aa that are stricly ketogenic

Lycine and leucine

22

Which aa make acetylCoA

leucine and lysine

23

what aa make fumarate and acetylCoA

aromatic aa:
1. Phe
2. Tyr
3. Trp

24

aromatic aa are both glucogenic and

ketogenic

25

What enzyme is required in Phe metabolism. What can result when you have deficiency of this enzyme

phenylalanine hydroxylase. PKU

26

What is the enzyme needed in homogentisate

homogentisate 1, 2 dioxygenase. Alkaptonuria can result if deficient.

27

what is PKU

1. autosomal recessive disease
2. deficiency in phenylalaline hydroxylase
3. all newborns tested at birth
4. treatment req low phenylalaline diet until adolescene
5. lack of treatment results in severe mental retardation.

28

What is a cofactor in many hydroxylase reactions.

Tetrahydrobiopterin. IMportant for neurotransmitters.

29

what does alkaptonuria cause

pigment buildup throughout the body and arthiritis like symptoms.

30

a deficiency in what enzyme results in albinism

tyrosinase

31

In humans what is glycine converted to

CO2 and NH4

32

In liver, what can serve as a substrate for lactate dehydrogenase and gets converted to oxalate

glyoxylate

33

what is the major component of kidney stones

Calcium oxalate

34

which aa are both glucogenic and ketogenic

3 aromatics: Phe, Tyr, Trp
1 branched chain: Ile

35

Which 2 aa are strictly ketogenic

leucine and lysine

36

What are inborn errors of metabolism

1. PKU: defect in phylalanine hydroxylase
2. Alkaptonuria: defect in homogentisate oxidase
3. maple syrup urine disease: defect in branched chain amino acid DH
4. methylmalonic acidemia: defect in methylmalonylCoA mutase
5. Homocystinuria: defect in cystathione synthase

37

How do you screen for inborn errors of metabolism

1. carrier status: preconception testing of parents
2. pre-implantation: test IVF embryos prior to implantation
3. Pre natal: Chorionic villus (10-12 week of pregnancy), amniocentesis (15-18 week of pregnancy) cordocentesis (after 17th week of pregnancy)