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Flashcards in Amino Acid Synthesis Deck (67):
1

What is the diff bet essential and non essential aa

We get essential aa from our diet. We can't get non essential aa from our diet--> we can synthesize them ourselves

2

What are the essential aa

Aromatics:
1. Phe
2. Trp

Basic:
3. Lys
4. His
5. Arg (insufficient in infants)

Branched chain
6. Ile
7. Leu
8. Val

9. Thr
10. Met (can be recycled)

3

What can be made from the transamination rxns?

1. Alanine (pyruvate)
2. Aspartate (oxaloacetate)
3. Glutamate (alpha KG)

4

What are the non essential aa

1. Serine
2. Cysteine
3. Glycine
4. Proline
5. Tyrosine
6. Alanine
7. Aspartate
8. Glutamate
9. Asparagine
10. Glutamine

5

What is a precursor to the production of urea

argenine; regenerate ornithine to restart cycle

6

What is a pseudo essential aa

argenine and methionine. Argenine bec essential when you have + N for ex in pregnant women and infants and you dont have this cycle to generate argenine. Methionine can be recycled in met homocysteine pathway.

7

What are the two reactions that require B12 as a cofactor

1. homocysteine pathway to form Met and THF
2. methylmalonylCoA --> succinyl CoA

8

Synthesis of non essential aa require ____ and ATP

NADPH

9

3 ____is required to make serine which condenses with _____ to make cysteine. It gets demethoxylated and become glycine

PG; homocysteine;

10

Pyruvate can directly transaminate to:

Alanine

11

Oxaloacetate can transanimtate to ______to make asparagine

aspartate

12

alpha KG can transaminate to _____ to make ______.

glutate; glutamine.

13

Phenylalanine + hydroxylase forms:

tyrosine

14

3 Phosphoglycerate is the starting point for which aa?

1. Serine
2. Glycine
3. Cysteine

15

Folate = ______ for glycine

methyl group acceptor

16

Once you have serine you can condense it with _____ to make cystathionine and rehydrate it with _____ to make ______

cystathione B synthase; cystathione gamme lyase; cysteine

17

Serine + _____ form cysteine

homocysteine.

18

cysteine has a backbone from serine and S group from:

homocysteine

19

If your deficient in cystathione synthase you will have an excess of _____ in your system which is prominent in cardiovascular disease.

homocysteine. It can result from THF, B12, or B6 deficiencies.

20

Asparagine synthesis uses ___as N donor

glutamine

21

Glutamine is the main repository for _____. Reversal of reaction produces ____

NH3. Glutamate

22

What are the different ways to make glutamate?

1. Transamination of alpha KG
2. Oxidative deanimation via glutamate dehydrogenase
3. Glutamine can be hyrolyzed with glutaminase
4. Several amino acids convert to Glu: Proline, Argenine/ornithine, Histidine

23

How do you make proline?

Catabolized to glutamate. The reversal of this reaction is the synthesis of proline.

24

How is tyrosine made?

By hydroxylation of phenylalanine; catalyzed by phenylalanine hydroxylase (which is deficient in PKU; requires tetrahydrobiopterin and NADPH)

25

what are some biological molecules derived from aa

1. GABA
2. Histamine
3. Thyroid hormones
4. norepinephrine
5. glutathione
6. creatine
7. serotonin
8. acetylcholine

26

Removal of COO- requires the enzyme _____ which uses ___ as a cofactor

decarboxylase; pyridoxine (vitamin B6)

27

addition of OH requires the enzyme ____ _____ which requires _____ and ____as a cofactor

hydroxylases and oxidases; tetrahydrobiopterin, and ascorbate

28

addition of methyl group requires the enzyme ____ which uses ____ and ____ as a cofacfor

methyl transferase; tetrahydrofolate, SAM

29

Nuerotransmitter signals are _____. Some are degraded of altered in synaptic cleft which include ____ via acetylcholinesterase and norepinephrine via _____ _____. Some neurotransmitters are endocytosed, such as ____.

transient; acetylcholine; monoamine oxidase; serotonin

30

Acetylcholine is derived from:

serine

31

choline + acetyl coA makes;

acetylcholine

32

serine turns into ____when you take off carbon dioxide which can turn into choline by methylating it via SAM

ethanolamine

33

What are some things that target acetylcholine metabolism

1. Botox: block Ach secretion
2. Cognex: slows acetylcholinesterase - potentiates it. Drug used for alzheimers
3. Sarin: blocks acetylcholinesterase. Once acetyl choline is released you get rigid convulsions.
4. Atropine: blocks acetylcholine receptor.

34

What is GABA derived from

glutamate (it gets decarboxylated via glutamate decarboxylase)

35

GABA is an _____neurotransmitter. It acts by increasing ____ permeability of post synaptic neuron

inhibitory; K+

36

GABBA is deficient in ______ and epilepsy

Huntington's chorea. Spasticity is in common. Things are hyper firing bc their not being more negatively charged.

37

GABA inhibition in brain is potentiated by

valium, librium, and alcohol

38

What stuff comes from tyrosine

1. Thyroid hormones; T3 and T4
2. Neurotransmitters/hormones: DOPA, dopamine, norepi, and epi
3. Pigment compounds: melanin

39

In people who have Parkinson's in where dopamine is deficient they treat them with ____bc its not charged.

DOPA

40

If DOPA gets shunted off to form dopaquinone from this you form ____

melanin

41

dopamine is increased in ____ and cocaine and amphetamines and decreased by ___ and haldol

schizophrenia; thorazine

42

Serotonin is derived from:

tryptophan

43

Trp is ____ then decarboxylated to form serotonin. Serotonin is a potent _____ found in brain, platelets and mast cells and is also considered a major regulator of mood.

vasoconstrictor.

44

what can serotonin be converted to. SSRIs block reuptake of serotonin.

melatonin in pineal gland.

45

Tryptophan is the precursor of ____, the ring portion of NAD and NADP

niacin

46

what is histamine derived from and how does this work

histadine; gets decarboxylated via histidine decarboxylase. Histamine acts as a potent vasodilator.

47

what is an H2 receptor antagonist that has similar structure to histamine

Tagamet

48

what is nitric oxide derived from

argenine via nitric oxide synthase. NO is a potent vasodilator and free radical which helps combat bacterial pathogens.

49

what is glutathione made from and what is it

1. Glutamate
2. Glycine
3. Cysteine

Its a strong reducing agent. There is no gene or mRNA for GSH.

50

what is creatine phosphate made from

1. argenine
2. glycine
3. methionone

51

creatine phosphate can phosphorylate ADP to ____. Both creatine and creatine phosphate are metabolized to ____. Inc excretion of creatinine is indicative of kidney damage

ATP; creatinine

52

Polyamines are positively charged and are made from____ Polyamines complex with ___ during compaction

ornithine and Met; DNA

53

what are the three polyamines

1. putrecine
2. spermidine
3. spermine

54

what is carnitine made from. what are the aa precursors?what is it used as?

trimethyllysine. Lysine, Met (SAM). acyl group carrier

55

where is heme synthesized

liver and bone marrow

56

what is the first step of heme synthesis

glycine + succinylCoA to make aminolevulinic acid (in mitochondria)

57

what is second step of HS

2 aminolevulinic acid to make prophobilinogen (in cytosol)

58

what is third step of HS

4 porphobilinogens to make linear tetrapyrrole (in cytosol)

59

what is the fourth step of HS

tetrapyrrole cyclization (in cytosol)

60

what is 5th step of HS:

side group rearrangments, addition of Fe++ (in mitochondria)

61

Tetrapyrrole cyclization requires enzyme uroporphyrinogen I synthase and the coenzyme:

uroporphyrinogen III cosynthase

62

Deficiencies in the Urophorphyrinogen enzymes can cause:

porphyrias
1. synthase (not making enough heme): acute intermittent; dark urine (liver defect), episodic bouts of irrational behavior, paralysis or severe pain, hypertension
2. cosynthase (dont get AP switch): congenital erythropoietic; premature destruction of RBS, red urine, skin is sensitive to light and red teeth

63

Fe++ is inserted by what to form heme

ferrochelatase

64

how is heme degraded

1. RBC break down in the spleen and release heme.
2. Heme gets degraded to biliverdin and CO and free Fe++
3. Biliverdin gets converted to bilirubin which is carried by albumin through the BS to the liver.
4. Bilirubin is converted to bilirubin diglucuronide for excretion into small intestine with bile.

65

What can liver damage or blocked bile ducts cause

jaundice

66

Heme oxygenase makes

carbon monoxide

67

what are the precursors for Heme

glycine and succinyl CoA