Biological Chemistry: Vitamins and Coenzymes

These flashcards cover key concepts from the Biological Chemistry lecture regarding Vitamins and Coenzymes, focusing on their functions, classifications, and biochemical roles.

What is the function of cofactors in enzymes?

Cofactors bind to the active site and assist in the reaction mechanism.

What is an apoenzyme?

An apoenzyme is an enzyme lacking its cofactor.

What is a holoenzyme?

A holoenzyme is an enzyme with its cofactor.

What type of cofactor stays with the enzyme?

A prosthetic group.

What is an example of an inorganic cation cofactor?

Metal ions such as Fe2+, Cu2+, or Zn2+.

What condition is caused by thiamine (B₁) deficiency?

Beriberi, which includes weight loss, heart problems, and neurological dysfunction.

What role does NAD(Nicotinamide adenine dinucleotide) play in the cell?

NAD acts as a soluble electron carrier involved in oxidation-reduction reactions, primarily in catabolic pathways.

How is riboflavin (B2) related to coenzymes?

Riboflavin is the precursor to flavin coenzymes FMN and FAD.

What is the significance of Vitamin C in biochemical reactions?

Vitamin C acts as a reducing agent and is important in maintaining metal cofactors, collagen synthesis, and acts as an antioxidant.

What is the function of tetrahydrofolate (THF)?

THF acts as a carrier for one-carbon units in various metabolic reactions.

What does Vitamin K contribute to in the body?

Vitamin K is involved in blood coagulation.

What are the main functions of Vitamin E?

Vitamin E protects cell membranes from oxidation, aids in red blood cell formation, and promotes circulatory health.

What happens to retinol when acting in photoreceptors of the eye?

Retinol acts as the precursor for the visual pigment 11-cis-retinal.

What deficiency results from a lack of Vitamin B12?

Pernicious anemia.

How is biotin related to carboxylase enzymes?

Biotin is active in carboxylase enzymes for the transfer of carbon units.