The central rod domain of protein Y is approximately 398 res

The central rod domain of protein Y is approximately 398 residues in length. The protein has an extensively distorted alpha-helical secondary structure. The helix repeats every 3.6 residues but has a pitch of 8.530 nm(compared to 0.540 nm for a true alpha-helix). What is the length (in A) of the rod domain? A

Solution

0.530nm/turn*398 residues*turn/3.6 residues

=0.530nm*398*1/3.6

=58.59 nm

=585.9Angstrom