Discussion:
Beta Bends or Reverse Turns
1. The amino acid sequence shown below represents a portion of a peptide bond obtained from a large protein:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
His - Ile -Thr - Arg - Phe - Phe - Pro - Cys - Met - Gly - Glu - Ala - Ile- Pro - His -
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Thr - Glu - Asp - Cys - Gln - Met - Ile - His - Cys - Pro - Arg - Lys - Gln - Pro - Tyr
(a) Determine where the chain would be more likely to show beta bends or reverse turns.
(b) Discuss where one would fin cross-linked disulfide bonds in this sequence.
(c) Would you consider this molecule to be in alfa helix formation?