BIOC 3560 Lecture Notes - Lecture 11: Citric Acid Cycle, Metabolic Pathway, Allosteric Regulation

• School: University of Guelph
• Department: Biochemistry
• Course: BIOC 3560
• Professor: N/ A

Document Summary

Metabolism --> sum of chemical transformations (anabolism and catabolism) Anabolic pathways don"t require energy --> false, synthesis requires energy. Products never cross over to other pathways --> false, acetyl coa can enter multiple pathways. Pathways are always linear (forward or backward) --> false, tca cycle is cyclic. Catabolism may also continue from acetyl-coa --> tca cycle. Rates of biochemical pathways depend on activity of enzymes which analyze each step. Activity of enzymes may be modified by many different mechanisms. Rate-limiting step is the slowest step in a metabolic pathway. Even if rapid enzymes are before and after, the alter enzymes are limited by the slow formation of product from the rate-limiting step. Enzyme may limit rate due to a modification. Every metabolic pathway has one or more enzyme-limited steps --> rate-limiting steps. Requires energy to move forward (activation energy, depends on atp substrate) Enzymes catalysing exergonic, rate-limiting steps are targets of metabolic regulation.