021 Collagen spl

Question 1

what is scurvy caused by?

Answer 1

vitamin c deficiency (severe)

Question 2

describe some symptoms of scurvy

Answer 2

• loss of collagen in body
• fragile blood vessels
• subcutaneous petechial (around hair follicle) haemorrhages
• inflammation and bleedings of gums
• loss of teeth
• poor healing wounds
• severe = degenerative heart changes causing cardiac emergency = death

Question 3

what vitamin is required for collagen synthesis?

Answer 3

vitamin c (ascorbate / ascorbic acid)

Question 4

if there is a vitamin C deficiency what is synthesised in collagen synthesis?

Answer 4

a soluble precursor protein is synthesised instead which is lacking hydroxyproline

Question 5

describe the process of collagen synthesis

Answer 5

• prolyl hydroxylase enzyme synthesises proline into hydroxyproline and requires vit c
• this enzyme contains Fe2+ and catalyses hydroxyproline from proline and decarboxylation of alpha-ketoglutarate, 1 Oxygen atom foes into each product which can then be used to form collagen strands

Question 6

what happens in collagen synthesis if vitamin c is absent?

Answer 6

• prolyl hydroylase is active for a short time and then rapidly undergoes inactivation as a result of oxidation of the reactive Fe2+ to Fe3+, vit c is needed to convert it back
• vit c is neither a co-enxyme or a substrate