6402
J . Am. Chem. SOC.1989, I 1 I , 6402-6407
region has for elucidating subtle changes in molecular structure. The similarities in the immediate ligation environment, as indicated by the first-shell data for stellacyanin and the other proteins, lead us to favor a model in which the variation in the X A N E S is attributed to changes in the (EXAFS nondetectable) axial ligand. With this in mind, it is interesting to note that the increase in absorbance a t 12317 eV (laccase < azurin, plastocyanin