Figure 2. Three dimensional model of the hemocyanin copper binding site from the spiny lobster (Panulirus interruptus) with mutations of the human tyrosinase gene associated with OCA1 marked in the equivalent positions to the tyrosinase polypeptide.

The coiled region represents the alpha-helical domains of the (P. interruptus) hemocyanin copper binding site. The ball and stick structures represent the histidine residues and the green circles are the copper atoms. The arrows represent human tyrosinase mutations associated with OCA1 in homologous regions of the hemocyanin copper binding site. Tyrosinase mutations in the copper binding region would most likely affect copper binding to the polypeptide or tyrosine binding to the copper atoms affecting tyrosinase activity.