Biochemistry 2280A Lecture Notes - Lecture 3: Dipeptide, Alpha Helix, Oligopeptide
Document Summary
Protein structure: proteins are linear polymers of amino acids, size: 50 to >30,000 amino acids. Nomenclature: dipeptide, tripeptide, oligopeptide: (3 to 10, polypeptide, protein: a molecule composed of one or more polypeptide chains. All proteins are polypeptides but not all polypeptides are proteins: a protein is a functional unit. Secondary structure: the alpha helix: spiral structure from the atoms backbones, oxygen, hydrogen, nitrogen contribute to the bonded helix shape, because of the spiral structure the hydrogen bonds take place between amino acids that are. 3 or 4 amino acids apart: 3. 6 amino acids per turn, alpha helices become this shape dependent on the primary structure, proline causes a kink in the helix, it is the helix breaker and destabilizes. Secondary structure: the beta sheet: polypeptides line up next to each other to make a sheet, each strand may not be straight and have kinks or sheets in them, secondary structure dictated by primary structure.