Effect of inhomogeneity in energy transfer through alpha helical proteins with interspine coupling

• The dynamics of homogeneous and inhomogeneous alpha helical proteins with interspine coupling is under investigation.
• The resulting dynamical equations are studied by perturbation analysis.
• The effect of inhomogeneity is analyzed in an alpha helical protein chain with interspine coupling.

The dynamics of homogeneous and inhomogeneous alpha helical proteins with interspine coupling is under investigation in this paper by proposing a suitable model Hamiltonian. For specific choice of parameters, the dynamics of homogeneous alpha helical proteins is found to be governed by a set of completely integrable three coupled derivative nonlinear Schrödinger (NLS) equations (Chen–Lee–Liu equations). The effect of inhomogeneity is understood by performing a perturbation analysis on the resulting perturbed three coupled NLS equation. An equivalent set of integrable discrete three coupled derivative NLS equations is derived through an appropriate generalization of the Lax pair of the original Ablowitz–Ladik lattice and the nature of the energy transfer along the lattice is studied.