... P5 and P2 for cpcE(4 2–2 76), P1 and P6 for cpcE( 1–2 72), P1 and P7 for cpcE( 1–2 74), P1 and P8 for cpcE( 1–2 37), P9 and P4 for cpcF(2 1–2 13), P10 and P4 for cpcF(1 0–2 13), P3 and P11 for cpcF( 1–1 60), ... (1988) In vitro attachment of bilins to apophycocyanin Specific covalent adduct formation at cysteinyl residues involved in phycocyanobilin binding in C -phycocyanin J Biol Chem 263, 1834 3–1 8349 ... rigid conformation in the a-CPC binding site There are 19 arginines, 13 lysines, three histidines and two tryptophans in CpcE, and 13 lysines, 10 arginines, one tryptophan and no histidine in CpcF...