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Biochemistry Flashcards

1
Q

Biochemistry

Items needed for de novo pyrimidine synthesis

A

Aspartate,CO2,Glutamine, Phosphate

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2
Q

Biochemistry

RLE for pyrimidine production

A

Carbamomyl Phosphate Synhtase II (CPS II)

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3
Q

Biochemistry

Items needed for de novo purine synthesis

A

Glycine, Asprtate, glutamine, CO2, THF

“GAG” mnemonic

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4
Q

Biochemistry

Orotic Aciduria

A

Inability to convert orotic acid to UMP (de novo pyriidine synthesis) because of UMP Synthase

AR

increased orotic acid in urine, megaloblastic anemia (doesnt improve with VitB12/folic acid), FTT, NO Hyperammonia

Tx: Oral uridine adminstration

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5
Q

Biochemistry

RLS for purine synthesis (PRPP –> –> –> IMP)

A

Glutamine PRPP Amidotransferase

KO via 6-MP

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6
Q

Biochemistry

UDP –> dUDP

A

via Ribonucleotide reductase

Inhibited by hydroxyurea

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7
Q

Biochemistry

Carbamoyl pohphsate

A

Involved in 2 metabolic pathways

  • De novo pyrimidine synthesis
  • Urea cycle
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8
Q

Biochemistry

dUMP –> dTMP

A

Thymidylate Synthase, inhibited by 5-FU (analog of uracil)

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9
Q

Biochemistry

DHF –> THF

A

Diydrofolate reductase, inhibited by MTX (euk) and TMP (Prok)

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10
Q

Biochemistry

Advantages of Purine Salvage Pathway

A

Reutilizes nucleotides,
prevents loss of ATPs needed for de novo purine synthesis,

neuclotides formed in this pathway inhibit de novo pathway at RLS

Decreased uric acid formation - end product of purine catabolism.

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11
Q

Biochemistry

HGPRT

A

Needed for conversion of Guanine to GMP and hypoxanthine to IMP

LESCH NYHAN Syndrome; X-linked Recessive

KO causes defective purine salvage, wth excess uric acid prdxn and de novo purine synthesis
Retardation, self mutilation, aggression, hyperuricema, gout,choreathetosis:

tx; allopurinol

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12
Q

Biochemistry

Cause of SCID

A

Adenosine deaminse deficienecy, needed for conversion of adenosine to inosine

Causes impaired DNA synthesis and hence decreased lymphocyte count

AR

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13
Q

Biochemistry

Nucleotide excision vs base excision vs mismatch repair

A

Nucleotide and BER = late damage, 1. NER is for bulky damage/pyrimidine dimers (xerdoerma pigmentosum)
2. BER is for damaged bases

  1. Early damage, can lead to HNPCC
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14
Q

Biochemistry

Immunohistochemical stains for intermediate filaments:

  • Vismentin
  • Desmin
  • Cytokeratin
  • GFAP
  • Neurofilaments
A
  • Connective tissue
  • Muscle
  • Epithelial cells
  • Neuroglia
  • Neurons
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15
Q

Biochemistry

Metabolism in:

  • Mitochondria
  • Cytoplasm
A

Mitochondria: Fatty acid oxidation, acetyl CoA production, TCA cycle, oxidative phosphorylation

Cytoplasm : fatty acid synthesis, HMP shunt, protein synthesis, steroid synthesis, cholesterol synthesis

Both: Heme synthesis, Urea Cycle, Gluconeogenesis (HUGs take two (both))

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16
Q

Biochemistry

Kinase
Phosphorylase
Phosphatase
Dehydrogenase
Carboxylase
A
  • Uses ATP to add high energy phosphate group onto substrate
  • adds inorganic phopshate without ATP
  • removes phosphate group
  • catalyzes oxidation/reduction reactions
  • transfers CO2 groups with help of biotin
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17
Q

Biochemistry

RLS glycolysis

A

Phosphofructokinase 1
+ : AMP, fructose 2,6 BO

  • : ATP, citrate
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18
Q

Biochemistry

RLS Gluconeogenesis

A

Fructose 1,6 Bisphosphatase
+: ATP

  • : AMP, fructose 2,6-BP
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19
Q

Biochemistry

RLS TCA cycle

A

Isocitrate dehydrogenase
+ : ADP

  • : ATP, NADH
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20
Q

Biochemistry

Glycogen synthesis RLS

A

glycogen synthase

+: glucose, insulin

-: epinephrine, glucagon

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21
Q

Biochemistry

Glycogenolysis RLS

A

Glycogen phosphorylase
+ : EPI, Glucagon, AMP

  • : Insulin, ATP
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22
Q

Biochemistry

RLS HMP Shunt

A

Glucose 6P Dehydrogenase
+ : NADP

-: NADPH

Deficient in G6PD deficiency, causing hemolytic anemia

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23
Q

Biochemistry

De novo pyrimidine synthesis RLS

A

Carbamoyl phosphate synthetase II (CPS II)

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24
Q

Biochemistry

De novo purine synthesis RLS

A

Glutamine-PRPP amidotrnasferase

-: AMP, IMP, GMP

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25
Q

Biochemistry

Urea Cycle RLS

A

Carbamoyl Phosphate synthetase I

+: N acetylglutamte

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26
Q

Biochemistry

Fatty acid oxidation RLS

A

Carnitine acyltransferace I

+: insulin, citrate
-: glucagon, palmitoyl CoA

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27
Q

Biochemistry

Fatty Acid Oxidation RLS

A

Carnitine acyltrnasferase I

-: Malonyl-CoA

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28
Q

Biochemistry

Ketogenesis RLS

A

HMG-CoA synthase

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29
Q

Biochemistry

Cholesterol synthesis RLS

A

HMG-CoA reductase

+: insulin, thyroxine
-: glucagon,cholesterol

target of statins

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30
Q

Biochemistry

NADPH is a product of and is used in :

A

HMP Shunt

  • Anabolic processes
  • respiratory burst
  • P450
  • Glutathione reductase
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31
Q

Biochemistry

Hexokinase vs. Glucokinase

A

Glucose –> Glucose -6 - phosphate

  • Hexokinase: high affinity (low Km) for glucose (can continue when blood glucose is low), low capacity (low Vm), feedback inhibited by product, fond in all tissues
  • Glucokinase: lower affinity for glucose (high Km) but high capacity (high Vmax), induced by insulin, found in regulatory cells like liver and pancreas. Hence at higher concnetrations, glucose is stored in liver
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32
Q

Biochemistry

Glycolysis:

3 regulatory enzymes

A

1) Hexokinase/glucokinase
2) PFK1
3) Pyruvate kinase (+F16BP, -ATP, -alanine)

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33
Q

Biochemistry

Key enzymes for gluconeogenesis

A

1) Pyruvate carboxylase
2) PEP carboxykinase
3) Fructose 1,6 bisphosphatase
4) Glucose-6-phosphatase

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34
Q

Biochemistry

Regulation by Fructose 2,6, bisphosphate

A

Fed state: + insulin, F26BP is promoting conversion of F6P to F16BP towards glycolysis via PFK-1 (more glycolysis)

Fasting state: +glucagon, F26BP is promoting conversion of F6P towards gluceoneogenesis (less glycolysis)

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35
Q

Biochemistry

Pyruvate Dehydogenase Complex

A

“Tender loving Care for Nobody”

-B1, B2, B3, B5, lipoic acid
(Thiamine, lipoic acid, CoA, FAD, NAD)

Pyruvate –> Acetyl CoA

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36
Q

Biochemistry

Pyruvate Metabolism’s different roles

A

1) Alanine aminotransferase (alanine created, carries amino groups to liver from muscle)
2) Pyruvate carboxylase (oxalacetate created, can replenish TCA cycle or be used in gluconeogenesis
3) Pyruvate dehydogenase (Acetyl CoA created, transition from glycolysis to TCA cycle)
4) Lactic acid dehydrogenase (lactate created, end of anaerboic glycolysis)

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37
Q

Biochemistry

GLUT transporters

A

Glut1: RBC, BBB - low level basal rate
Glut2: hepatocyte/pancreas, small intestines, kidneys, important for regulation, highest Km
Glut3: neurons/placenta
Glut4: Skeletal/adipose tissues (requires insulin)

Gllut5: speratocytes and GI tract (fructuse transport)

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38
Q

Biochemistry

Fabry Disease

A

XLR
Deficient in alpha galactosidase
accumulates ceramide trihexoside

Sx: angiokeratomas, cardiac, and renal involvement, painful neuropathy

39
Q

Biochemistry

Gaucher Disease

A

Lysosomal Storage disease : deficiency of beta-glucosidase . Affects bone, liver, spleen, bone marrow and brain. Pancytopenia, bone fractures, joint pain “Crinkled paper” bone marrow cells .

AR

40
Q

Biochemistry

Hurler syndrome

A

autosomal recessive
lysosomal storage disease

deficiency of a-L-iduronidase - accumulation of mucopolysaccharides heparan sulfate and dermatan sulfate in heart, liver, brain, and other organs

gargoylism, corneal clouding, hepatosplenomegaly, developmental delay

41
Q

Biochemistry

Hunter syndrome

A

XLR
Enzyme: Iduronate sulfatase
Buildup: Dermatan & heparan sulfate

gaygoylism, hepatosplenomegaly, developmental delay (no corneal couding like Hurler)

42
Q

Biochemistry

Niemann Pick Disease

A

AR
Def: Sphingomyelinase
Accumulation of spingomyelin

Sx: hepatosplenomegaly,cherry red spot in macula,foam cells, progressive neurodegeneration

43
Q

Biochemistry

Tay Sachs Disease

A

AR
Def: B hexosaminidase
Excess GM2 ganglioside builds up

Chery red spot in macula,progressive neurodegeneration, no hepatoslenomegaly

44
Q

Biochemistry

Krabbe’s Disease

A
  • AR
  • Galactrocerbrosidase deficiency

-buildup of galactosyl sphingosine and galactrocerbroside

Progressive neurodegeneration, developmental delay, optic atrophy, large globiod bodies in brain and white matter, fatal early in life, seizures

45
Q

Biochemistry

Metachromic Leukodystrophy

A

AR
Arylsulfatase A deficiency. Sulfatides (cerebroside sulfate) ; Accumulates cerebroside sulfate ( glycolipid of myelin ) in CNS & PNS –demyelination - UMN/LMN sx, periph neuropathy. ataxia, dec attention span

Late infantile form within 1 year spastic quadriplegia, blind, dementia, seizures, death by 5-6y.

46
Q

Biochemistry

Collagen subtypes and associated disesase

A

Type 1 - bones, scar, tendons, ligaments (Def: osteogenesis imperfecta)
Type 2 - cartilage, nucleous pulposis

Type 3 - reticular (granulation, skin, blood vessels, lymphatics, BM (def causes Ehlers Danlos syndrome)

Type 4 - basement membrane (Alport syndrome)

Be So Totally Cool Read Books

47
Q

Biochemistry

Essential, Acidic, Basic Amino Acids

A

Essential (needed in diet): MVH(glucogenic), IFTW(both), LK(ketogenic)
Acidic: Asp, Glu

Basic: Arg, Lys, His.

PVT TIM H a LL

48
Q

Biochemistry

amino acid derivatives

Tryptophan, histidine, phenylalanine, glycine, arginine, glutamate

A
  • Niacin, serotonin (tryptophan)
  • histamine ( histidine)
  • epinephrine, norepinephrine, dopamine, Dopa, thyroxine ( Phenylalanine –> tyrosine)
  • Heme (glycine)
  • Creatinine, urea,NO (arginine)
  • GABA, glutathione (glutamate)
49
Q

Biochemistry

ALT, AST

A

ALT: Alanine + aKG Glutamate + pyruvate

AST: glutamate + oxaloacetate aKg + aspartate

50
Q

Biochemistry

Von Gierkes Disease

A

Deficiency in Glucose-6-phosphatase, therefore cell cannot release glucose from glycogen for gluconeogenesis.

Findings: Severe fasting hypoglycemi, increased glycogen in liver, increased blood lactate, hepatomegaly, kidneymegaly, enterocytemegaly

AR, Tx: feedfrequently

51
Q

Biochemistry

Pompe’s Disease

A

Type II Glycogen Storage Disease

Lysosomal alpha-1,4-glucosidase deficiency

finginds: cardiomegaly and systemic findings leading to early death

***Pompe’s trashes the pump…heart, liver and muscle

52
Q

Biochemistry

cori’s disease

A

glycogen storage type III
deficiency of debranching enzyme - a-1,6-glucosidase

milder form of type I with normal blood lactate

gluconeogenesis intact

AR

53
Q

Biochemistry

McArdle’s Disease

A

glycogen phosphorylase deficiency (glycogen storage disorder V) in the skeletal muscle

AR,

Sx: fatigue and cramps, myoglobinuria

forearm ischemia test is abnormal

increased glycogen in muscle that cant be broken down

Muscle cells swell and lyse bc of H2O, causing rhabdomyolysis

54
Q

Biochemistry

Metabolic fuel use during exercise

A

After seconds: stored ATP then creatine phosphate
After minutes: anaerobic glycolysis

After hours: Aerobic metabolism and FA oxidation

55
Q

Biochemistry

Fasting and starvation

A 
fed state (After meal) : Glycolysis/aerobic resp
 fasting (bw meals)  hepatic glycogenolysis (major, hepatic GNG, adipose release FFA (minor)

Starvation days 1-3 : hepatic glycogenolysis (up to 24 hrs), Adipose release FFA , Muscle and liver use FFA , Hepatic GNG from lactate/alanine, and fr adipose glycerol and propionyl coA (from odd chain FFA)

Starvation after 3 days: Adipose stores ( ketone bodies major source of energy for brain and heart)–fat people live longer. After these are depleted, v ital protein degradation accelerates–>organ failure and death.

56
Q

Biochemistry

Lipid Transport

A

LDL-cholesterol from liver to tissues
HDL-transport cholesterol from periphery to liver

VLDL-deliver TGs to peripheral tissue

IDL-byproduct when VLDL degraded in serum, delivers TGs and cholesterol to liver

57
Q

Biochemistry

major apolipoproteins

A
  • E = mediates remnant uptake (on all)
  • AI = activates LCAT (on HDL)
  • CII = LPL cofactor (on CM and VLDL)
  • B48 = mediates CM secrection (on CM and CM remnant)
  • B100 = binds LDL R (on VLDL, IDL, LDL)
58
Q

Biochemistry

Lipoprotein functions

A

Lipoproteins are composed of varying proportions of cholesterol, TGs, and phospholipids. LDL and HDL carry most cholesterol. LDL transports cholesterol from liver to tissues. HDL transports cholesterol from periphery to liver.

59
Q

Biochemistry

Lipoprotein Functions (CM,VLDL, IDL)

A
  • CM: Delivers dietary TGs to peripheral tissues and choelsterol to the liver as a CM remnant (which are depleted of triacylglycerols), secreted GI Epi cells
  • VLDL: Delivers hepatic TGs to peripheral tissues; secreted by liver
  • IDL: FOrmed in degredation of VLDL, delivers TGs and cholesterol to the liver
60
Q

Biochemistry

Lipoprotein Functions (LDL, HDL)

A
  • LDL: Delivers hepatic cholesterol to peripheral tissues; formed by hepatic lipase modification of IDL in peripherl tissues, taken up by receptor mediated ednocytosis
  • HDL: Mediates cholesteral transport from periphery to liver; is respository for apoC and apoE. Secreted from liver and intestines
61
Q

Biochemistry

Hyperchylomicronemia

A

Type I familial dyslipidemia
- due to lipoprotein lipase deficiency or altered apolipoportein CII

→ increased chylomicrons and elevated blood levels of TGs and cholesterol

→ pancreatitis, hepatosplenomegaly, eruptive/pruritic xanthomas (NO ↑ risk of atherosclerosis)

62
Q

Biochemistry

Familial hypercholesterolemia

A
  1. Autosomal dominant disorder
  2. Missing or decreaed receptors for LDL in liver
  3. Negative feedback fails, results in high LDL and cholesterol Serum
  4. accelerated atherosclerosis, tendon xathnomas, corenal arcus
63
Q

Biochemistry

Hypertriglyceridemia

A

Increased blood VLDL and TG

AD

Hepatic overprodxn of VLDL

Causes pancreatitis

64
Q

Biochemistry

Abetalipoproteinemia

A

-Autosomal recessive
-No apoB48 or apoB100 (hence decreaedCM and VLDL synthesis/secretion)
-Fatty enterocytes on intestinal bx
Findings: -Acanthocytosis of RBCs, Failure to thrive, ataxia, night blindness

Decreased Vit A, D, E, K
-Treat with vitamin E

65
Q

Biochemistry

Lesch-Nyhan Syndrome

A

Defective purine salvage due to absence of HGPRT. Results in excess uric acid production .
Findings: retardation, self-mutilation, gout, aggression.

66
Q

Biochemistry

B12 vs. Folate Deficiency

A
  • B12 Deficiency is usually accompanied by elevated concentrations of blood homocysteine and methylalonic acid
  • Folate deficiency results in only elevated homocysteine

-folate deficiency does not cause neuro sx

Test for IF in blood (signifies B12 deficiency)

67
Q

Biochemistry

arsenic toxicity

A

inhibiting lipoic acid (binding to the SH-group)

  • Vomiting
  • Rice water stools
  • Garlic breath

Needed for PDH and OAA complex

68
Q

Biochemistry

Key enzymes in Glycolysis

A

1) hexokinase/glukokinase
2) PFK1 (RLS)
3) Pyruvate kinase

69
Q

Biochemistry

Key Enzymes in gluconeogenesis

A
  1. Pyruvate carboxylase (req B7)
  2. PEP carboxylase
  3. Fructose 1,6 Bisphophatase (RLS)
  4. Glucose 6 Phosphatase (absent in muscle cells)

Occurs primarily in liver. Enzymes found also in kidney,gi epi. Def of enzymes causes hypoglycemia. Odd chain fatty acids yields propionyl CoA which can enter TCA cycle and undergo gluconeogneis

70
Q

Biochemistry

Pyruvate dehydrogenase complex deficiency

A

=backup of substrate (pyruvate, alanine), lactic acidosis, most cases due to X-linked mutation in E1-a but can also be due to cofactor deficincies

sx: neurologic defects, usually starting in infancy
tx: increased intake of ketogenic nutrients (high fat contant, high lysine/leucine)

71
Q

Biochemistry

Key TCA Cycle enzymes

A
  1. Citrate synthase
  2. Isocitrate dehydogenase (RLS)
  3. alpha ketoglutarate dehydrogenase
72
Q

Biochemistry

Oxidative Phosphorylation Poisons

A

Electron Transport Inhibitors - directly inhibit electron transport, causing a decrease in the proton gradient and blocks ATP synthesis. Ex: Rotenone, CN - , antimycin A, CO.
ATPase Inhibitors - directly inhibit mitochondrial ATPase, causing an increase in the proton gradient. No ATP is produced because electron transport stops. Ex: Oligomycin
Uncoupling Agents - increase permeability of the membrane, causing a decrease in proton gradient and increase in oxygen consumption. ATP synthesis stops, but electron transport continues. This produces heat. Ex: 2,4-DNP, ASA, thermogenin in brown fat.

73
Q

Biochemistry

HMP Shunt (pentose phosphate pathway)

A

Provides source of NDAPH from G-6-phoshpate

  1. Glucose 6 Phosphate dehydregnase is RLS enzyme
74
Q

Biochemistry

HMP Shunt (pentose phosphate pathway)

A

Provides source of NDAPH from G-6-phoshpate

  1. Glucose 6 Phosphate dehydregnase is RLS enzyme
75
Q

Biochemistry

Enzymes of Respiratory (oxidative) Burst

A
  1. NADPH Oxidase ( def = Chronic Granulomatous Dz)
  2. Superoxide Dismutase
  3. Myeloperoxidase
  4. Glutathione Peroxidase
  5. Glutathione Reductase
  6. G6PD (deficiency causes G6PD deficiency, PNH)
    - first 3 are in phagolysosome
    - last 3 are in neutrophil cytoplasm
76
Q

Biochemistry

Essential Fructosuria

A

Involves a defect in fructokinase . Autosomal recessive. A benign, asymptomatic condition since fructose does not enter cells
Symptoms: fructose appears in blood and urine (osmotic diuresis)

Disorders of fructose metabolism cause milder symptoms than analogous disorders of galactose metabolism

77
Q

Biochemistry

Fructose intolerance

A
  • Hereditary deficiency of aldolase B . Autosomal recessive. Fructose-1-phosphate accumulates ⇒ ⇓in available phosphate, which results in inhibition of glycogenolysis and gluconeogenesis.
  • Symptoms → hypoglycemia, jaundice, cirrhosis, vomiting.

• Tx → ⇓intake of both fructose and sucrose (glucose + fructose).

78
Q

Biochemistry

Galactokinase deficiency

A

Hereditary deficiency of galactokinase. Galactitol accumulates if galactose is present in deficiency diet. Relatively mild condition. Autosomal recessive. Symptoms: galactose appears in blood and urine, infantile cataracts. May initially present as failure to track objects or to develop a social smile.

79
Q

Biochemistry

Classic galactosemia

A
  • absence of galactose-1-phosphate uridyltransferase
  • autosomal recessive
  • more severe than galactokinase deficiency
  • accumulation of galactitol and other toxic intermediates
  • failure to thrive, jaundice, hepatomegaly, infantile cataracts, mental retardation
  • Tx: exclude galactose and lactose from diet
80
Q

Biochemistry

Urea Cycle Key Enzymes

A
  1. CPS 1 (RLS)

2. Ornithine Transcarbamoylase

81
Q

Biochemistry

Ornithine Transcarbamoylase (OTC) deficiency

A

most common urea cycle disorder

X-linked recessive

often evident in first few days of life but may be late onset (girls)

Findings: orotic acid in blood and urine, decreased BUN, symptoms of hyperammonemia

82
Q

Biochemistry

Ornithine Transcarbamoylase (OTC) deficiency

A

most common urea cycle disorder, interferes with ability to elimate ammonia, excess carbamoyl phopsphate convereted to orotic acid

X-linked recessive

often evident in first few days of life but may be late onset (girls)

Findings: orotic acid in blood and urine, decreased BUN, symptoms of hyperammonemia

83
Q

Biochemistry

Phenylketonuria

A

Autosomal recessive; decreased p henylalanine hydroxylase or tetrahydrobiopterin cofactor (malignant/atypical PKU); tyrosine becomes essential (does not help atypical PKU);
Findings: mental retardation, growth retardation, seixures, ecxema, musty/mousy body odor;

Tx: decreased Phe and increased Tyr in diet

84
Q

Biochemistry

Alkaptonuria

A
  • deficiency of homogentisic acid oxidase in degradative pathway of TYROSINE to fumarate
  • formation of alkapton bodies=> dark urine and dark CT, brown pigmented sclera

(homogentisic acid toxic to cartilage)

AR, benign

85
Q

Biochemistry

Homocystinuria (3 types)

A

3 forms (AR; excess homocysteine; cysteine becomes essential): 1. Cystathionine synthase deficiency- (tx: decrease Met and increase Cys, B12, and folate in diet) 2. Decreased affinityof cystathionine synthase for pyridoxal phosphate (increase Vit B6 in diet) 3. Homocysteine methyl transferase (requires B12) deficiency

86
Q

Biochemistry

Homocystinuria (findings)

A

Findings: increased homocysteine in urine, mental retardation, osteoporosis, tall stature, kyphosis, lens subluxation (down and in) and atherosclerosis (stroke and MI)

All due to excess homocysteine and cysteine becoming essential

87
Q

Biochemistry

Cystinuria

A
  • ↓ tubular reabsorption of cystine
  • inherited deficiency of COAL transporter (cystine,ornithine, lysine, and arginine) in PCT
  • AR, tx with good hydration and alkalization (acetazolamide)
88
Q

Biochemistry

Maple syrup urine disease

A
  • Blocked degradation of branched amino acids(Ile, Leu, Val) due to ↓ α-ketoacid dehydrogenase. - Causes ↑ α-ketoacids in the blood, especially Leu.
  • C auses severe CNS defects, mental retardation, and death.Urine smells like maple syrup.
89
Q

Biochemistry

Hartnup Disease

A

AR defect in neutral amino acid transporter on renal and intestinal epithelial cells

Causes tryptophan excretion in urine and decreased absorption from gut, leading to pellagra

Pellagra (remember tyrosine is needed to make niacin, serotonin, melatonin

90
Q

Biochemistry

Alanine cycle and cori cycle

A

Alanine cycle: Pyruvate to alanine by ammonium in muscle. Goes to liver, NH3 taken by aKetoglutarate, alanine back to pyruvate which is used to make glucose.

Glucose cycle: Glucose in muscle is broken down. Pyruvate can be used in alanine cycle, Lactate exits muscle back to liver, where gluconeogenesis occurs

91
Q

Biochemistry

key enzymes in glycogen metabolism

A

glycogen synthase
(glycogenesis) - RLS

glycogen phosphorylase

(glycogenolysis)

92
Q

Biochemistry

What 2 enzymes are key to the coordination of Fatty Acid metabolism?

A
  1. Acetyl-CoA carboxylase (synthesis)

2. Carnitine palmitoyl trnasferase/acyltransferase I (degradation)

93
Q

Biochemistry

Carnitine Deficiency

A

Can’t transport long-chain-fatty-acids into mitochondria=tox accumulate

Sx: weakness, hypotonia, hypoketotic hypoglycemia

94
Q

Biochemistry

Ketogenesis and cholesterol synthesis RLS

A

Hmg CoA Synthase (ketogenesis)

HmGCoA Reductase (cholesterol genesis) ==> TARGET FOR STATINS

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