Spin-density distribution in the copper site of azurin

A 95 GHz pulsed deuterium ENDOR study has been performed on single crystals of ozurin from Pseudomonas aeruginosa selectively deuteroted at the C-beta position of the copper-coordinatin4 cysteine 112. Complete hyperfine tensors of the two deuterium atoms have been obtained, which reveal identical isotropic ports. Analysis of the hyperfine tensors provides insight into the spindensity delocalization over the cysteine ligand Approximately 45% of the spin density in the paramagnetic site can be attributed to copper and 30% to sulfur.