BINDING OF TRIAZINES AND TRIAZINONES IN THE Q(B)-BINDING NICHE OF PHOTOSYSTEM-II

A series of 20 triazines (derivatives of alkylamino-4-benzylamino-6-ch loro-1,3,5-triazines) and 37 triazinones (derivatives of 3-alkyl-4-ami no-6-phenyl-1,2,4-triazin-5-ones) is tested for inhibitory potency in photosynthetic electron flow through photosystem II of wild type Chlam ydomonas reinhardtii and of five mutants with aminoacid substitutions in the D 1 protein at valine 219, alanine 251, phenylalanine 255, seri ne 264, and leucine 275. The data are used for computer modelling of.t he possible location of the compounds within a three dimensional model of the Q(B)-binding niche of the D1 protein.