Molecular Modelling of the Interactions between Optically Active Triazine Herbicides and Photosystem II

Abstract

Abstract The Q B binding site of photosystem II in green plants displays stereoselectivity for the (S′) stereoisomer of the α-methylbenzyl derivative of atrazine but not for derivatives with smaller substituents such as sec-butyl. We have shown that interactive models reflect the experimental data by determining the intermolecular energies between the D1 protein binding region (resi­dues Leu 210 to Val 280) and the triazine analogs. The intermolecular energy was calculated by van der Waals and electrostatic interactions after energy minimization of the combined structures to reduce inter and intramolecular strain. On the basis of these assumptions the role of stereoselectivity for optically active triazines was site responsible such stereoselectivity was identified.