Phylogenetic Implications of Phycocyanobilin and C‐phycocyanin

C‐phycocyanin has been prepared from algae representative of various orders and families in the Cyanophyceae and Rhodophyceae. The chromophore phycocyanobilin has been cleaved, purified and crystallized as the dimethyl ester. Each sample was compared with reference phycocyanobilin dimethyl ester and found to be identical on the basis of absorption spectral (ultraviolet, visible and infrared) and chromatographic properties. The phylogenetic implications of these results are discussed.