Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

2013/2014 > Purines/Pyrimidines, AA Synthesis and Metabolism, Catecholamines > Flashcards

Purines/Pyrimidines, AA Synthesis and Metabolism, Catecholamines Flashcards

1
Q

First step of purine synthesis

A

Ribose 5 Phosphate (pentose phosphate pathway) comes 5-phosphoribosyl-1-pyrophosphate (PRPP) using ATP via PRPP synthetase. Inhibited by IMP, GMP, AMP.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Amidophosphoribosyl transferase reaction

A

Second step of purine synthesis, also the rate limiting step. PRPP + Glutamine –> 5 phosphoribosylamine via amidophosphoribosyl transferase. 5 Phosphoribosylamine becomes Inosine monophosphate eventually (which has hypoxanthine as its base). Inhibited by IMP, AMP, and GMP.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

AMP Synthesis

A

IMP + Aspartate +GTP –> Adenosuccinate –> AMP + Fumarate. This reaction is inhibited by AMP.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

GMP Synthesis

A

IMP + NAD –> Xanthylate

Xanthylate + Glutamine + ATP –> GMP + Glutamate. This reaction is inhibited by GMP.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How do XMP’s become XDP’s?

A

Easily, utilizing nucleoside monophosphate kinase.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How do XDP’s become XTP’s?

A

Easily, utilizing nucleoside diphosphate kinase.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Salvage Pathway Purpose

A

When purines are degraded to free bases, they can be salvaged rather than excreted.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Salvage Pathway for A

A

Adenine + PRPP —> AMP + PPi Via Adenine phosphoribosyl transferase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Salvage Pathway for G/Xanthine

A

Guanine/Hypoxanthine + PRPP –> GMP/IMP + PPi via hypoxanthine/guanine phosphoribosyl transferase.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Lesch-Nyhan Syndrome

A

HGPRT deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Purine Metabolism

A

Guanine –> Xanthine –> Uric Acid

Adenine –> Hypoxanthine –> Xanthine –> Uric acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Purpose of Uric Acid

A

To neutralize ROS in blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Gout

A

Uric Acid Crystals cause inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Pyrimidine Synthesis First Step

A

Glutamine + CO2 –> Carbamoyl Phosphate via CPS II

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

CPS II and reaction

A

Found in the cyto of all cells, not only in liver mitochondria like CPS I. Not increased by NAGA.
Glutamine + CO2 –> Carbamoyl Phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Rate Limiting Step of Pyrimidine Synthesis

A

Carbamoyl Phosphate + Aspartate –> N-Carbamoyl Aspartate (via Aspartate Transcarbamoylase)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

N-Carbamoyl Aspartate

A

Makes UMP, which makes UDP, which makes UTP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How does UTP become CTP?

A

UTP + Glutamine –> CTP + Glutamate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Orotate

A

Intermediate in pyrimidine synthesis. Accumulates in people with Ornithine Transcarbamylase deficiency.

20
Q

Deoxyribose Formation

A

Ribose –> Deoxyribose, but not the other way around. Occurs via ribonucleotide reductase.

21
Q

Ribonucleotide Reductase Structure

A

B1 has overall activity site and specificity site. B2 has catalytic site with tyrosines and thiols

22
Q

How does RR work?

A

Using a tyrosine to create a radical. Thiols will be oxidized, then reduced by thioredoxin, thioredoxin reductase, FADH2, NADPH.

23
Q

How is RR regulated at the overall activity site?

A

Increased activity by ATP, shut down by dATP.

24
Q

C3 Family of AA’s

A

Alanine, Tryptophan (becomes Alanine and acetyl CoA), Glycine, and Cysteine

24
Q

How is RR regulated at the specificity site?

A

ATP generates d Pyrimidines. dTTP decreases pyrimidines and increases dGTP synthesis. dGTP causes dATP generation, which shuts down the mechanism.

25
Q

Alanine Metabolism

A

Alanine + AKG –> Pyr + Glu via GPT

26
Q

Glycine Metabolism

A

Glycine–> Serine (Via Serine Transhydroxymethylase)

Serine –> Pyruvate

27
Q

Cysteine Metabolism

A

Cysteine –> Pyruvate + S

28
Q

C4 Family of AA’s

A

Aspartate, Asparagine, Methionine, Valine, Threonine, Isoleucine

29
Q

Aspartate Metabolism

A

Aspartate + AKG –> Glutamate + OAA via GOT

30
Q

Asparagine Metabolism

A

Asparagine –> Aspartate + NH3 via Asparaginase

31
Q

Methionine, Valine, Threonine, Isoleucine Metabolism

A

Become propionyl CoA –> Methylmalonyl CoA –> Succinyl CoA

32
Q

C5 family of AAs

A

Glutamate, Glutamine, Histidine, Arginine

33
Q

Glutamate Metabolism

A

Glu + NAD –> AKG + NH3

34
Q

Glutamine Metabolism

A

Glutamine –> Glutamate + NH3 via Glutaminase

35
Q

Histidine Metabolism

A

Histidine become formamino glutamine, which becomes formamino THF

36
Q

Arginine Metabolism

A

Arginine –> Urea + Ornithine via Arginase

37
Q

BCAAs and their metabolism

A

Valine, Isoleucine, Leucine undergo transamination with AKG to form their respective alpha ketoacid. This is then decarboxylated by BCAlphaKetoacid Dehydrogenase to create CoA and CO2. This second reaction uses a E3 mechanism like pyruvate dehydrogenase.

38
Q

Phenylalanine Metabolism

A

Phenylalanine + Tetrahydrobiopterin + O2 –> Tyrosine via Phenylalanine Hydroxylase

39
Q

PKU

A

Caused by a deficiency in Phenylalanine Hydroxylase

40
Q

Tyrosine Metabolism

A

Tyr –> Fumarate and Acetoacetate

41
Q

Mixed Function Oxidation

A

Where the atoms of an O2 are split up into different products.

42
Q

Catecholamine Synthesis

A

Occurs in adrenals. Tyrosine –> DOPA (Via tyrosine hydroxylase and THB) –> Dopamine (via DOPA decarboxylase) –> NE (Via DA Betahydroxylase) –> Epi (Via SAM methyltransferase)

43
Q

5-HT Synthesis

A

Tryptophan –> 5HTP (Via Tryptophan Hydroxylase + THB) –> 5-HT (via DOPA decarboxylase) –> NAcetylSerotonin –> Melatonin

44
Q

What three amino acids make up Glutathione?

A

Glutamate, Cystine, Glycine

2013/2014 (23 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions