BIOL1006 Lecture Notes - Lecture 3: Egg White, Covalent Bond, Pepsin
Document Summary
Each protein has its own unique sequence of amino acids and the interactions between these amino acids create a specify shape. This shape determines the protein"s function, from digesting protein in the stomach to carrying oxygen in the blood. If the protein is subject to changes in temperature, ph, or exposure to chemicals, the internal interactions between the protein"s amino acids can be altered, which in turn may alter the shape of the protein. Although the amino acid sequence does not change, the protein"s shape may change so much that it becomes dysfunctional, in which case the protein is considered denatured. Pepsin, the enzyme that breaks down protein in the stomach, only operates at a very low ph. At higher phs pepsin"s conformation, the way its polypeptide chain is folded up in three dimensions, begins to change. The stomach maintains a very low ph to ensure that pepsin continues to digest protein and does not denature.
