Copper-substituted forms of the wild type and C42A variant of rubredoxin

The interplay between Cu(I) and Cu(II) in sulfur-rich protein environments is studied in the copper-substituted forms of the wild-type rubredoxin from Desulfovibrio vulgaris Hildenborough and of its variant C42A-rubredoxin. The results emphasize the redox instability of CuII-(S-Cys)n centers.