The lipid portion of a typical bilayer is about 30 thick. a. Calculate the minimum number

Question:

The lipid portion of a typical bilayer is about 30 Å thick.
a. Calculate the minimum number of residues in an α-helix required to span this distance.
b. Calculate the minimum number of residues in a β-strand required to span this distance.
c. Explain why α-helices are most commonly observed in transmembrane protein sequences when the distance from one side of a membrane to the other can be spanned by significantly fewer amino acids in a β-strand conformation.
d. The epidermal growth factor receptor has a single transmembrane helix. Find it in this partial sequence: