DM Week 2

Question 1

Which compound inhibits succinate dehydrogenase?

Answer 1

Malonate

Question 2

Which compound inhibits aconitase?

Answer 2

Fluoroacetate

Question 3

Thiamine Pyrophosphate requires which co-factor?

Answer 3

Vitamin B1 (Thiamine)

Question 4

Which are the high energy compounds of phosphate?

Answer 4

Phosphoenolpyruvate
1,3 Bisphosphoglycerate
Phosphocreatine

Question 5

Complex 1 of Electron transport chain

Answer 5

NADH dehydrogenase

Question 6

Complex 2 of electron transport chain

Answer 6

Succinate Dehydrogenase

Question 7

Complex 3 of electron transport chain

Answer 7

Cytochrome c reductase

Question 8

Complex 4 of electron transport chain

Answer 8

Cytochrome c oxidase

Question 9

Inhibitor of ATP synthase complex

Answer 9

Oligomycin

Question 10

Inhibitors of NADH dehydrogenase (3 count)

Answer 10

Rotenone
Amytal
Piericidin A

Question 11

Inhibitors of Cytochrome Reductase

Answer 11

Antimycin A

Question 12

Inhibitors of Cytochrome Oxidase (4 count)

Answer 12

Cyanide
Azide
Carbon Monoxide
Hydrogen Sulfide

Question 13

Atracyloside binds to which side of the ANT transporter?

Answer 13

Outward facing portion (inter membrane space)

Question 14

Bongkrekic Acid binds to which side of the ANT transporter?

Answer 14

Inward facing portion (matrix)

Question 15

2 types of uncouplers

Answer 15

DNP (2,4-Dinitrophenol)
ASA (aspirin)

-Dissipate H+ gradient, no ATP generation, Increase oxygen utilization; Cause hyperthermia

Question 16

Hereditary mitochondrial disease associated with defect in Complex I

Answer 16

Leber’s Hereditary Optic Neuropathy

Question 17

Aminoglycoside antibiotics causes what in early childhood?

Answer 17

Deafness

Question 18

Disease presentation:
-Paralysis of eye muscles and degeneration of retina
* Cardiac problems or congestive heart failure
* Muscle and skeletal weakness
* Ataxia (coordination problems)
* Diabetes, dementia and other mental illnesses

Answer 18

Kearns-Sayer
-Due to deletion in mitochondrial DNA

Question 19

Clinical Features: Strokes, myopathy (weak muscles), muscle twitching,
dementia, and deafness

Answer 19

Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and
Stroke-like episodes (MELAS)

Question 20

Myoclonus is usually the first symptom
followed by:
– Seizures, ataxia, muscle weakness, worsening
eye sight and hearing loss

Answer 20

Myoclonic Epilepsy; Ragged Red Fibers (MERRF)

Question 21

Liver Aldolase B deficiency

Answer 21

Hereditary Fructose Intolerance

Question 22

Continued dietary fructose/ sucrose/ sorbitol → hepatocellular
failure and jaundice
* Urinalysis shows reducing sugar (fructose) that is NOT glucose

Answer 22

Hereditary Fructose Intolerance
-Eliminate Fructose and sucrose from the diet

Question 23

Aldose Reductase is present in which organs?

Answer 23

rich in lens, retina, peripheral
nerves and seminal vesicles

Question 24

Classical triad: liver damage, developmental
delay and cataracts
* Urine positive for reducing sugar (not glucose)

Answer 24

Classical Galactosemia
-Deficiency in Galactose 1-phosphate uridyl transferase (GALT)

Question 25

Substrate for galactitol formation and enzyme needed?

Answer 25

From galactose, enzyme needed is aldose reductase

Question 26

Galactose 1-phosphate buildup is due to which enzyme deficiency?

Answer 26

Galactose 1-phosphate uridyl transferase (GALT)

Question 27

Enzyme deficiency in non-classical galactosemia and presentation

Answer 27

Galactokinase, cataracts only formed

Question 28

Urine dipstick shows reducing sugar but no clinical symptoms. What is the disease?

Answer 28

Benign Fructosuria

Question 29

Enzyme that plays active role in lipolysis

Answer 29

Hormone Sensitive Lipase

Question 30

What state stimulates hormone sensitive lipase?

Answer 30

Low levels of insulin (fasting state)

Question 31

Beta-oxidation occurs in which organelle?

Answer 31

Mitochondria

Question 32

Which disease is characterized by hypoglycemia and hypoketosis and fatty acids in the urine?

Answer 32

Medium Chain Acyl-CoA Dehydrogenase (MCAD) deficiency

Question 33

Labs show: Elevated serum CK-MM and myoglobin in urine: Skeletal muscle damage * Lipid droplets in muscle biopsy -Muscle weakness and cardiomyopathy Which disease is likely?

Answer 33

Myopathic carnitine deficiency

Question 34

Unable to tolerate aerobic activity (Cramps during aerobic exercise) – Lipid deposits (triglycerides) in skeletal muscle – Myoglobinuria and elevated serum CK-MM levels – Affects muscle isoform

Answer 34

CPT-II Deficiency

Question 35

Contains ‘hypoglycin A’ - inhibitor of MCAD, from eating unripe akee fruit

Answer 35

Jamaican Vomiting Sickness

Question 36

Acetoacetate, 3-hydroxybutyrate (- hydroxybutyrate) and acetone are what kind of molecules?

Answer 36

Ketone bodies

Question 37

Ketogenesis requires which enzyme?

Answer 37

Mitochondrial HMG CoA synthase

Question 38

Which 2 amino acids are exclusively ketogenic?

Answer 38

Leucine and Lysine

Question 39

What is the rate limiting step for cholesterol synthesis?

Answer 39

HMG CoA reductase

Question 40

What is the coenzyme needed for cholesterol synthesis?

Answer 40

NADPH

Question 41

Amino Acid precursor to serotonin

Answer 41

Tryptophan

Question 42

Anti-cancer drug that is a folate analog and inhibits the formation of active tetrahydrofolate

Answer 42

Methotrexate

Question 43

Amino acid involved with methylmalonic aciduria

Answer 43

Valine

Question 44

Enzyme that produces glutamine in the brain

Answer 44

Glutamine Synthetase

Question 45

Enzyme that produces ammonia in the kidney renal tubules

Answer 45

Glutaminase

Question 46

Enzyme needed to form free ammonia

Answer 46

Glutamate dehydrogenase

Question 47

Compounds that require Vitamin B1/Thiamine Pyrophosphate for cofactor

Answer 47

1) Alpha-Ketoglutarate Dehydrogenase 2) Pyruvate Dehydrogenase 3) BC alpha-Keto acid Dehydrogenase