Question

***TYPED PLEASE. NOT HAND WRITTEN*********

Please give clear and detailed answer(one paragraph at least). Also add a link to at least one source/reference you used.

Certain enzyme-driven reactions require cofactors many of which can be obtained through the diet. If the diet is deficient in these cofactors, it can halt the reaction causing a disease state. An example of this is ascorbic acid. When deficient in the diet it can lead to the loss of teeth, scaly skin, bleeding in the joints and muscles, and the inability to heal wounds.The incidence of this deficiency is very low due to the fortification of many foods and the wide-spread access to fruits and vegetables in the modernized world however pockets of this disease tend to pop up in regions with armed conflict.

Describe the biological reaction/mechanism associated with ascorbic acid that could lead to the symptoms listed above when the dietary intake is deficient and why areas of armed conflict are often seen as pockets of this deficiency.

***TYPED PLEASE. NOT HAND WRITTEN*********

Answer 1

Deficiency of ascorbic acid leads to the mentioned symptoms like loss of teeth, scaly skin, bleeding in the joints and muscles, and the inability to heal wounds. L-Ascorbate prevents scurvy by helping in the deposition and maintenance of intracellular substances in mesenchymal tissues. It acts as an electron-donor and reductant, and as a cofactor in several hydroxylations.

L-Ascorbate helps in the post-translational hydroxylation of proline and lysine residues in immature collagen (protocollagen) molecules. This enables their cross-linking into normal mature collagen fibrils.

L-Ascorbate acts as an electron-donor hence as a co-factor in hydroxylating dopamine to noradrenaline. It also helps in hydroxylation of carnitine synthesis. Ascorbic acid deficiency causes a decline in carnitine which results in low energy production, muscular fatigue and lassitude. It is needed in oxidations in tyrosine metabolism, thus its deficiency causes a rise in serum tyrosine and urinary elimination of p-hydroxy phenylpyruvate and homogentisate in scurvy. The requirement of ascorbic acid for the absorption and utilization of iron is the reason for anemia during ascorbic acid deficiency. Ascorbate acts as an electron donor in tissue oxidoreduction reactions.