1. QUATERNary Structures and Denaturing of Proteins Chapter 14.11- 14.12

2. Quaternary Structure -The highest level of protein organization, Quaternary Structure, refers to proteins with more than one polypeptide chain. -Broken up into Subunits: 1.Hemoglobin 2.Collagen 3.Integral Membrane Proteins

3. Hemoglobin Made up of 4 chains, called “Globins” 2 α chains of 141 amino acid residues. 2 β chains of 146 amino acid residues. Each Globin Chain encompasses an iron-containing heme unit. Conjugated Proteins- Proteins that contain non-amino acid portions. Prosthetic Group- The non-amino acid of a protein.

4. Hemoglobin: The Revenge Hemoglobin is not merely separated into the two aforementioned groups. As a fetus our Hemoglobin has a greater affinity for oxygen than as a born human. This is because the mother supplies the blood for the fetus. This also helps eliminate symptoms of Cell Anemia.

5. Collagen  A grand example of another quaternary structures in proteins.  Constituted by triple helix units called tropocollagen!  After a long time, they become insoluble.  Cross-linking allows helixes to connect and creates the stabilized formation of proteins structures.

6. Integral Membrane Proteins  Traverse a protein layer either partly or completely.  33.3333% of proteins are estimated to be Integral Membrane Proteins.  This allows polar proteins to remain stable in a non-polar environment.  2 Quaternary Structures: + 6 to 10 α-helices crossing the membrane + β-barrels 8, 12, 16 or 18 antiparallel sheets.

7. Denaturation of Proteins Denaturation- the process of the loss of a secondary, tertiary, or quaternary proteins through the use of a chemical or physical agent. Agents of Denaturation: Heat, 6m Urea, Detergents, Acids/bases, Salts, Reducing Agents, Heavy Metals, and Alcohol. Each Denaturation Agent affects a different part of the protein! The Denaturation Process is the process that happens when one boils an egg.

8. Collagen 2: The Sequel Reducing agents can…reduce… -S-S- bonds to form –SH groups. This is what makes your hair curly I with a straightener. Heavy Metal ions form salt bridges which denatures milk and eggs. Denaturing also sterilizes skin before injections. Denaturing is reversible if the changes are minimal.