title: On the linkages between chromophore and protein in biliproteins, VII. Amino acid sequence in the chromophore regions of C-phycoerythrin from Pseudanabaena W 1173 and Phormidium persicinum.
abstract: Bilipeptides from all chromophore regions were prepared by trypsin digestion of C-phycoerythrin from Pseudanabaena W 1173 and Phormidium persicinum. Analytical separation and quantitative determination of bilipeptides was achieved by isoelectric focusing, preparative isolation by gel chromatography and ion-exchange chromatography. Amino acid analysis revealed cysteine as the only amino acid common to all chromopeptides. Amino acid sequences were determined by Edman degradation and the dansyl-Edman technique. Sequences are different in all 5 and 6 chromophore regions, respectively. Possible homologies are discussed. A thioether linkage between ring A of the chromophore and cysteine was found in the bilipeptides (as before in biliproteins). A second linkage (serine ester) was found in only one peptide (CM 4.I from Pseudanabaena W 1173). This peptide absorbs as cation at a longer wavelength (559 nm) than the other bilipeptides (542 - 550 nm).
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000458:Cyanobacteria / Q000032:analysis*; D010446:Peptide Fragments / Q000032:analysis; D010799:Phycoerythrin; D010860:Pigments, Biological; D013045:Species Specificity
chemical_list: D000596:Amino Acids; D010446:Peptide Fragments; D010860:Pigments, Biological; D010799:Phycoerythrin