The three-His triad in Dke1: comparisons to the classical facial traid

The effect of the three-His motif in Dke1 on the geometric and electronic structure of the [Fe.sup.II] centers is analyzed by a combination of absorption, CD, MCD and VTVH MCD spectroscopies and DFT calculations. The studies have helped in understanding the effects of perturbation of the facial triad ligation of the non-heme ferrous enzymes on their geometric and electronic structure and also their contributions to reactivity.