Rusticyanin is a cupredoxin in archaea and proteobacteria
Rusticyanin is a copper-containing protein which is involved in electron-transfer. The members of this family are found in archaea and proteobacteria. It is a cupredoxin, or blue-copper protein due to its color. Rusticyanin, extracted from the bacteria Thiobacillus ferrooxidans is redox active down to PH 2.0 and the acid-stable cytochrome c is the primary acceptor of the electron. This organism can grow on Fe2+ as its sole energy source. Rusticyanin is thought to be a principal component in the iron respiratory electron transport chain of T. ferrooxidans.
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