Figure 3
(A–C) Cartoon representation of αβ monomer (A), α3β3 trimer (B) and (α3β3)2 hexamer (C) of Nostoc sp. R76DM phycocyanin. The α- and β-subunits are represented by cyan and green colors, respectively. PCB chromophores are presented in brown color. Substituted residues of β-subunit are represented by red colour. (D–F) Superimposed view Nostoc sp. R76DM phycocyanin (N-PC) and Microchaete diplosiphon phycocyanin (MD-PC) (PDB ID: 1CPC) for amino acids substitutions in N-PC. The N-PC and MD-PC are presented in green and red color, respectively. (D) Substitution Phe → Tyr at α18 is compensated by Glu → Asp at β87 position. (E) Substitution Phe → Trp at β18 is compensated by Met → Ala at β79 position. (F) Substitution Ala → Val at β56 is compensated by two substitutions, Leu → Ile at β83 and Met → Leu at β86 position.
