Chapter 13, Problem 13B.4ST

Interpretation Introduction

Interpretation:

The confirmation of polypeptide flavodoxin has to be checked whether it has helical or sheet-like confirmation based on the given values.

Concept Introduction:

Karplus equation:

The magnitude of ${}^3{J}_{\text{HH}}$ in an $\text{HCCH}$ group depends on the dihedral angle, $\varphi$ between the two $\text{C-H}$ bonds.  The variation is given by Karplus equation as follows,

$\begin{array}{l}{}^3{J}_{\text{HH}}=\text{A}\text{+}\text{B}\text{cos}\varphi \text{+}\text{C}\text{cos}\text{2}\varphi \\ \text{where,}\\ \text{J}\text{-}\text{coupling}\text{constant}\end{array}$