Vitamin B6 - Pyridoxine

Question 1

origin

Answer 1

1. plant: greein veggies, grains -> hydrolized to -ol/-al
2. animal: liver, egg, meat, milk, yeast
3. microbial synthesis from PALP to -ol/-al

Question 2

how is B6 transported

Answer 2

passive transport:

• pyridoxal is less hydrophilic -> albumin-bound-
• pyridoxol doesnt need carrier

Question 3

where is B6 found

Answer 3

all forms, in all cell types, no storage

Question 4

how in B6 excreted

Answer 4

as pyridoxic acid

Question 5

how are the different forms made

Answer 5

pyridoxol makes pyridoxal

pyridoxal makes: -acid, -amine and PALP

Question 6

where in the formation does schiff base formation occur

Answer 6

NH3 from pyridoxamine -> pyridoxal

Question 7

name the biochemical roles of B6

Answer 7

1. transamination
2. Decarboxylation
3. heme synthesis
4. Trp -> Niacin
5. Amino acid dehydration (degradation)
   (show ex for all in this topic!)

Question 8

deficiency

Answer 8

1. neural damage (needed to form GABA)
2. anaemia: heme synth decr.
3. pellagra: niacin synth decr.
   - slow growth
   - dermatitis

Question 9

antivitamin of B6

Answer 9

(PALP synthesis) isoniazid: drug against tuberculosis/mycobacterium cause decr. B6 uptake!