Question

Discuss the two levels of enzyme regulation. Define the terms constituative, regulated, and inducible enzymes. Give examples of each.

Answer 1

Enzyme regulation
1. Phosphofructokinase 1 is inhibited by ATP and citrate if ATP levels are suffient and decrease glycolysis.
Phosphofructokinase 1 is increase by AMP or fructose 2,6 bisphosphate if ATP is needed to cells and glycolysis active.

2. Pyruvate kinase is inactivated by phosphorylation to pyruvate kinase phosphate.
It it gets dephosphorylate by phosphatase it become active.

Constitutive enzymes - Enzymes needed at the same level all of the time. Eg, Enzymes of glycolysis.

Regulated enzymes - Enzymes needed under some conditions but not others. Eg, Lac operon enzymes made only presence of lactose.

Inducible enzymes - The process that turn ON the transcription of a gene. Eg, glucokinase of glycolysis.