title: The complete amino acid sequence of both subunits of C-phycocyanin from the cyanobacterium Mastigocladus laminosus.
abstract: The amino acid sequences of both subunits of the C-phycocyanin from the thermophilic cyanobacterium Mastigocladus laminosus have been determined. The alpha-chain consists of 162 amino acid residues and has a molecular weight of 18000, whereas the beta-chain consists of 172 residues and has a molecular weight of 19400. For the first three quarters of their length the polypeptide chains are 31% homologous, whereas there is no significant homology in the final quarter up to the C-terminus. This could mean that the introduction of an additional chromophore binding site in the last quarter of the beta-chain during evolution was achieved via a large number of point mutations or by exchange of the whole C-terminal part in an ancestral gene.
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000458:Cyanobacteria / Q000032:analysis*; D046911:Macromolecular Substances; D008970:Molecular Weight; D010446:Peptide Fragments / Q000032:analysis; D010798:Phycocyanin / Q000302:isolation & purification; D010860:Pigments, Biological / Q000302:isolation & purification
chemical_list: D000596:Amino Acids; D046911:Macromolecular Substances; D010446:Peptide Fragments; D010860:Pigments, Biological; D010798:Phycocyanin