BIO 327 Chapter Notes - Chapter 4: Motor Protein, Ubiquitin, Electrophoresis
Document Summary
**not all possible protein sequences are used by nature: Because relatively few of all the possible sequences create structures with stable energy minima. Synthetic proteins, especially peptides can have any sequence. Distribution of polar/nonpolar amino acids important in folding of protein. Hydrophobic interaction: hydrophobic sides of amino acids are forced together to minimize disruption on h-bond network: unfolded proteins are to be denatured. Alpha: generated from single polypeptide chain that turns into cylinder: formed from h-bond at every 4th amino, abundant in proteins embedded in cell membranes, coiled-coil: 2 or 3 helices wrap around each other. Beta: h-bonds form between segments of a polypeptide chin that lie side by side: parallel (segments in same orientation) or antiparallel, permit formation of amyloid fibers. These can occur between r groups or parts of the polypeptide backbone: tertiary: 3d organization of secondary structures, protein domains, quaternary: organization of protein complexes, weak non-covalent bonds enable polypeptide chain to fold into specific conformation.
