Wk 1 - Vitamins, Cofactors, Enzymes Flashcards
1
Q
Apoenzyme vs Holoenzyme
A
Apo = NOT reactionary Holo = Reactionary
2
Q
Prosthetic cofactors
A
Bind tightly to active site for lifetime of enzyme
Ex: FAD cofactor of succinate dehydrogenase
3
Q
Transient cofactors
A
Cofactor is released after the reaction happens
Ex: NAD+ cofactor of alcoholdehydrogenase
4
Q
What are NADH/NADPH derived from? What’s it found in?
A
Niacin
- Meat, whole grains
5
Q
NADH
A
- Fuel oxidation
- Can transfer 2 electrons at a time
- Transient
6
Q
Niacin deficiency
A
Pellagra
- Dermatitis
- Diarrhea
- Dementia
7
Q
NADPH
A
- Biosynthetic/detoxification
… Essentially adding more O2 molecules to make them more soluble/easier to excrete - Transient
- Can power reaction of the enzyme
8
Q
FMN and FAD
A
- Vitamin precursor: riboflavin (B2)
- Accept/transfer single electrons one at a time
- Reaction: create/break double bonds
- Found in milk, eggs, legumes
9
Q
FMN/FAD deficiency
A
- Cheilosis (sores around mouth)
- Glossitis (redder/smoother tongue than normal)
- Can happen with GI disorder/malnutrition
Diagnosis
- Presenting symptoms
- Erythrocyte glutathione assay
10
Q
Ascorbic Acid
A
4 functions
- Nonenzymatic anti-oxidant
- Redox cofactor for: collagen synthesis, neurotransmitter synthesis, oxygen sensing
Found in vitamin c
- Citrus fruits and vegetables
11
Q
Oxygen Sensing
A
- Ascorbic acid has to do with HIF propyl hydroxyls activity
- Oxygen around? HIF ubiquiniated and degraded
- No oxygen? HIF acts as a TF to inhibit glycolysis and produce ATP without oxygen
12
Q
TPP
A
Reaction: decarboxylations
Vitamin precursor: Thiamine
- Found in meat and legumes
Prosthetic cofactor
13
Q
TPP/thiamine deficiency
A
Beriberi
- Headache
- Malaise
- Peripheral neuropathy
14
Q
Lipoate
A
Reaction: acetyl transfer
Prosthetic cofactor
No deficiency known
15
Q
Coenzyme A
A
Vitamin precursor:
