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Flashcards in Amino Acids Deck (120)
0

Essential amino acids groups

1. Glucogenic
2. Glucogenic/ketogenic
3. Ketogenic

1

Form of amino acids that are found in proteins

L form

2

All.....amino acids need to be supplied in the diet

Essential

3

A ketogenic amino acid is an amino acid that....

can be degraded directly into acetyl CoA through ketogenesis

4

Essential glucogenic amino acids

1. Methionine (Met)
2. Valine (Val)
3. Histidine (His)

5

Glucogenic amino acid is an amino acid that.....

Can be converted into glucose through gluconeogenesis

6

Essential ketogenic amino acids

1. Leucine (Leu)
2. Lysine (Lys)

7

Essential glucogenic/ketogenic amino acids

1. Isoleucine (ile)
2. Phenylalanine
3. Threonine
4. Tryptophan

9

Acidic amino acids and charge

Aspartic acid (Asp)
Glutamic acid (Glu)
both negative

10

Basic amino acids and charge

Arginine (Arg) - positive
Lysine (lys) - positive
Histidine (his) - no charge

10

Amino acids required during periods of growth

Arginine
Histidine

11

The most basic amino acid

Arginine

12

Amino acids of histones

Arginine
Lysine

13

Amino acid catabolism result in the formation of

Common metabolites (pyruvate, acetyl CoA e.g.), which serves as metabolic fluids

14

Amino acid catabolism result in excess

Nitrogen (NH3)

15

Nitrogen is converted to

Urea and excreted by the kidneys

16

Urea cycle - reactions and locations

- CO2 + NH3 + 2ATP --> carbamoyl phosphate + 2ADP + P ( carbamoyl phosphate synthase 1 and N-acetygkutamate as a cofactor) (Mitochondria)
- Carbamoyl phosphate + ornithine --> citrulline Ornithine transcarbamylase) (Mitochondria)
- Citruline + aspartate + ATP--> AMP + PPi + Argininosuccinate (arginossuccinate synthetase)
Cytoplasm
- Argininosuccinate --> arginine and fumarate (arginosuccinase) Cytoplasm
- arginine + H20 --> UREA + Ornithine (Arginase) cytoplasm

17

Urea productuon reaction
Location

Arginine + H2O --> ornithine + Urea
Enzyme arginase
Location:cytoplasm of liver

18

Urea production location

Cytoplasm of liver

19

Location of ornithine transcarbamylase action

Mitochondria of the liver

20

Ornithine transcarbamylase reaction
Location

Carbamoyl phosphate + ornithine --> citrulline
Mitochondria

21

Arginosuccinate: next step

To arginine and fumarate (arginosuccinase)

22

Urea structure

NH2 (NH3)
|
C=O (CO2)
|
NH2 (aspartate)

23

Arginosuccinate: next step

To arginine and fumarate (arginosuccinase)

24

Urea is excreted by

Kidney

25

Urea cycle site

Both Mitochondria and cytoplasm of the liver

26

Enzyme responsible for urea production

Arginase

27

Aminoacids(NH3) to a-ketoacids causes

A ketoglutarate to glutamate(NH3)

28

Glutamate(NH3) to a-ketoglutorate causes

Pyruvate to alanine (NH3)

29

Cori cycle

Glucose to pyruvate to lactate (muscle)
Lactate to pyruvate to glucose (liver)
Glucose back to muscle

30

Alanine cycle (cahill cycle)

Pyruvate-alanine (muscle)
Alanine(NH3) to pyruvate (liver) converting a-ketoglutorate to glutamate(NH3)
pyruvate to glucose (liver)
Liver back to muscle

31

Hyperammonemia can be divided to

1. Acquired (liver disease)
2. Hereditary (urea cycle enzyme deficiencies

32

Transport of ammonia by

Alanine and glutamate

33

Hyperammonemia results in

Excess NH4+

34

Excess NH4+ in hyperammonemia results in

a-ketoglutarate depletion, leading to inhibition of TCA cycle

35

Carbamoyl phosphate synthetase I cofactor

N-acteylglutammate

36

Hyperammonemia treatment

1. Limit protein diet
2. Phenylbutyrate or Benzoate (bind aminoacid and lead to excretion) may be given to decrease ammonia levels
3. Lactulose to acidify the GI tract and trap NH4+ for exertion
4. Rifamixin to decrease colonic ammoniagenic bacteria

37

N-acetyglutamate deficiency leads to

Hyperammonemia

38

N-acetyglutamate deficiency is identical to

Carbamoyl synthetase I deficiency

39

Ornithine trancarbamylase deficiency mode of inheritance

XR (vs other urea cycle enzyme deficiency which are autosomal recessive)

40

Lab findings that suggest N-acetyglutamate deficiency and clinical presentation

Increased ornithine with normal urea cycle enzymes
1. poorly regulated respiration and body Q
2. poor feeding
3. developmental delay
4. intellectual disability

41

Most common urea cycle disorder

Ornithine trancarbamylase deficiency

42

Urea cycle enzymes deficiencies are AR except

Ornithine trancarbamylase deficiency --> XR

43

Ornithine trancarbamylase deficiency / pathophysiology

Interferes with the body's ability to eliminate ammonia

44

Ornithine trancarbamylase deficiency/ often evident in (age)

First few days of live, but may present with late onset

45

Ornithine trancarbamylase deficiency /what is happening with the excess carbamoyl phosphate

Is converted to orotic acid

46

Ornithine trancarbamylase deficiency findings

1. Increased orotic acid blood and urine
2. Decreased BUN
3. Symptoms of hyperammonemia
4. NO MEGALOBLASTIC ANEMIA (vs orotic aciduria)

47

Orotic aciduria vs Ornithine trancarbamylase deficiency (lab)

Ornithine trancarbamylase deficiency has no megaloblastic anemia

48

Amonoacid and vitamin to heme

Glycine to porphyrin (B6)
Porphyrin to heme

49

Amina acid responsible for heme synthesis
Vitamin responsible for heme synthesis

Glycine
B6

50

Histamini synthesis (amino acid and vitamin)

Histidine to histamine (B6)

51

Tryptophan participate in the synthesis of

Niacin (NAD, NADP)
Serotonin
Melatonin

52

Ammonia intoxication

1. Slurring of speech
2. Tremor (asterixis)
3. Somnolence
4. Vomiting
5. Cerebral edema
6. Blurring vision

53

Arginine is responsible for the synthesis of

1. Creatinine
2. Urea
3. Nitric oxide (BH4 as a cofactor)

54

Synthesis of melatonin (aminoacid and vitamin)

Tryptophan to serotonin (B6+BH4)
Serotonin to melatonin

55

Nitric oxide synthesis (amino acid and coafactor)

Arginine to nitric oxide (BH4)

56

Glutamate is responsible for the synthesis of

1. GABA (B6)
2. Glutathione

57

Tyrosine synthesis

Phenylalamine to tyrosine (Phenylalamine hydroxylase and BH4)

58

Aminoacid responsible for thyroxin synthesis

Tyrosine (tyrosine is synthesized by phenylalamine and BH4)

59

Tyrosine (and phenylalamine) is responsible for the synthesis of

1. Thyroxine 2. Dopa 3. Melanin 4. Dopamine. 5. NE 6. Epi

60

Tyrosine to DOPA (enzyme and cofactor)

Tyrosine hydroxylase
BH4

61

DOPA

Dihydrixyphenylalamine

62

DOPA to melanin

Tyrosinase

63

Tyrosinase deficiency

Albinism

64

Phenylalanine deficiency

Phenylketonurua

65

DOPA decarboxylase inhibitor

Carbidopa

66

DOPA to Dopamine

DOPA decarboxylase
Vit B6

67

Dopamine to Norepinephrine

Dopamine β hydroxylase
Vitamin C

68

Dopamine metabolite

Homovallinic acid

69

Norepinephrine metabolite

Normetanephrine to vanillymandelic acid

70

Norepinephrine to epinephrine

SAM

71

SAM (norepinephrine to epinephrine) regulation

Cortisol +

72

Epinephrine metabolites

Metamephrine to vanillylmandenic acid

73

Tyrosine, except dopamine, can be converted to

Homogentisic

74

Homogentisic to maleyacetoacetic (TCA cycle as fumarate)

Homogenstisate oxidase

75

Homogepentisate oxidase deficiency

Alkaptonuria

76

BH4

Tetrahydrobiopterin

77

Phenylketonuria pathophysiology

1. Phenylalamine hydroxylase deficiency
2. Tetrahydrobiopterin deficiency (BH4) (malignant)

78

PKU

Phenylketonuria

79

Tyrosine/PKU/diet

Tyrosine becomes essential

80

PKU/urine

Increased phenylketones in urine

81

PKU symptoms

1. Intellectual disability 2. Growth retardation 3. Seizures 4. Fair skin
5. Eczema 6. Musty body odor

82

PKU treatment

- Decrease phenylalamine and increased tyrosine in diet
- avoid artificial sweetener aspartame which contain phenylamines
- Tetrahydrobipterin supplementation (BH4)

83

PKU mode of inheritance

AR
Pleiotropy

84

Maternal PKU

Lack of proper dietary therapy during pregnancy. Infant with microcephal, intellectual disability, growth reterdation, congenital heart defects

85

PKU screening

2-3 days after birth (normal at birth because of maternal enzyme during fetal life)

86

Phenylketones

Phenylacetate
Phenyllactate
Phenylpyruvate

87

Disorder of aromatic amino acid metabolism

Musty body odor

89

PKU patients must avoid

artificial sweetener aspartame which contain phenylamines

89

Alkaptonuria - pathophysiology

Congenital deficiency of homogentisate oxidase in the degradative pathway of tyrosine to fumarate --> pigment-forming homogentistic acid accumulates in tissue

90

Alkaptonuria mode of inheritance

AR

92

Alkaptonuria is a benign or a malignant disease

Benign

92

Phenylketonuria incidence

1/10,000

93

Alkaptonuria findings

1. Dark connective tissue and sclerae (ochronosis)
2. Urine turns black on prolonged exposure to air
3. Debilitating arthralgias (Homogentisic acid toxic to cartilage)

94

Homocystinuria mode of inheritance

AR

95

Homocystinuria results in excess

Homocysteine

96

Niacin synthesis (amino acid and vitamin)

Tryptophan to niacin (B2, B6)

97

Homocystinuria findings

1. Increased homocysteine in urine 2. Intellectual disability 3. Osteoporosis 4. marfanoind habitus 5. Kyphosis 6. Lens subluxation (downward and inward). 7. Thrombosis. 8. Atherosclerosis (stroke and MI)

98

Cysteine synthesis

Homocysteine + serine to cystathionine (cystathionine synthase +B6)
Cystathionine to cysteine

99

Methionine synthesis

Homocysteine to methionine (methionine synthase +B12)

100

Cystathionine synthase deficiency treatment

Low Methionine, increase cysteine and B12 and folate in diet

101

Homocysteine methyltransferase (methionine synthase) deficiency - treatment

Increased methionine in diet

102

Low affinity of Cystathionine synthase for pyridoxal phosphate treatment

Increased B6 and cysteine in diet

103

Amino acids affected in cystinuria

COLA (mnemonic)
Cysteine, ornithine, lysine, arginine

104

Cystinuria

Hedereditary defect of renal proximal convoluted tubular and intestinal amino acids trasnporter for Cysteine, Ornithine, Lysine, Argnine (COLA)

105

Excess cysteine in urine

Precipitation of hexagonal cysteine stones

106

Cystinuria mode of inheritance

AR

107

Cystinuria frequency

1/7000

108

What is cystine

2 cysteines commected by a disulfide bond

109

Cystinuria diagnosis

Urinary cyanide-nitroprusside test

110

Cystinuria treatment

1. Urinary alkalization (eg.potasium citrate, acetalozamide)
2. Chelating agents solubility of cystine stones
3. Good hydration

111

Homocystinuria types and mode of inheritance

1. Cystathione synthase deficiency
2. Low affinity of cystathione synthase for pyridoxal phosphate
3. methione synthase deficiency
ALL AR

112

Maple syrup urine disease pathophysiology

Blocked degradation of branched amino acids (isoleucine, leucine, valine) due to decreased a-ketoacid dehydrogenase (B1).

113

Branched amino acids

1. Isoleucine
2. Leucine
3. Valine

114

Maple syrup urine disease lab

Increased a ketoacids in the blood, especially those of leucine

115

Maple syrup urine disease mode of inheritance

AR

116

Maple syrup urine disease complication

1. Severe CNS defects
2. Intellectual
3. Death

117

Maple syrup urine disease treatment

Restriction of lucine, isoleucine, valine in diet
Thiamine supplement

119

Marple syrup urine presentation

1. Urine smells like maple syrup/burnt sugar
2. poor feeding
3. vomiting

120

homocysteine methyltransferase is AKA

homocysteine methyltransferase