In addition, electron transfer rates for stellacyanin are faster than for other type I copper proteins suggesting stellacyanin is more solvent accessible at the active site. The exact function of stellacyanin is unknown. However, given the fact that type I copper proteins are involved in electron transfer and stellacyanin appears to be associated with the plant cell wall, it is suggested that it is involved in oxidative cross-linking reactions to build polymeric material making up the cell wall.
In addition, the rates of electron transfer for stellacyanin are more rapid than those for other type I copper proteins, indicating that stellacyanin is more exposed at its active site. The specific role of stellacyanin remains unknown, but considering the involvement of type I copper proteins in electron transfer and stellacyanin's connection to plant cell walls, it is proposed that stellacyanin is involved in cross-linking reactions to construct cell wall polymers.