Crustacyanin
In-game article clicks load inline without leaving the challenge.
Crustacyanin is a carotenoprotein biological pigment found in the exoskeleton of lobsters and blue crabs and responsible for their blue colour. β-Crustacyanin (β-CR) is composed of two stacked astaxanthin carotenoids that absorb at λ = 580–590nm (2.10–2.14 eV). α-crustacyanin (α-CR) is an assembly of eight β-CR protein dimers. It is a 320 kDa (atomic mass) complex containing 16 astaxanthin molecules. Although the β-CR dimer has a peak wavelength of 580nm, α-CR exhibits a bathochromic shift to 632nm; the mechanism and function of the additional wavelength shift is not understood.