sequence of amino acid residues

         stabilized by disulfide bonds

          local arrangement of the backbone

         stabilized by hydrophobic interactions

          3-dimensional structure of a protein

         stabilized by side chain interactions

            arrangement of multiple subunits

          stabilized by backbone atom bonds or interactions

         stabilized only by covalent bonds

         G – E – T – R – K is an example

         stabilized only by hydrogen bonds

          an α-helix is an example

         stabilized by ionic interactions

          a β-pleated sheet is an example

          disrupted by denaturation

          not disrupted by denaturation

5-7. Answer with (H) α-helix; (P) parallel β-sheet; (N) antiparallel β-sheet; or (A) all of these.

         has a small dipole

         the secondary structure of myoglobin

         requires C=O – – –  H – N

          may include proline

           side chains alternate above &
               below

           side chains of every 4^th residue interact

          rarely includes proline

            2 strands connected by a b -bend

             has weak hydrogen bonds:

            side chains are all outside

             .