title: Reconstitution of an allophycocyanin trimer complex containing the C-terminal 21-23 kDa domain of the core-membrane linker polypeptide Lcm.
abstract: Allophycocyanin (AP) was isolated from extracts of the cyanobacterium Mastigocladus laminosus. A fraction enriched in AP-associated polypeptides with apparent molecular masses of 21-23 kDa in SDS-PAGE, was isolated on a preparative scale and identified as a homologous mixture of C-terminal fragments of the core-membrane linker polypeptide Lcm. The complex (alpha AP beta AP)3.21-23 kDa was reconstituted and characterized by sucrose density gradient ultracentrifugation, absorption, fluorescence emission and circular dichroism spectroscopy. The 21-23 kDa polypeptides were found to induce spectral changes in AP similar to those induced by the small core linker polypeptide Lc8.9. Possible functions of the complex in phycobilisomes are discussed.
authors.affiliation: Botanisches Institut der Universität, München, Bundesrepublik Deutschland.
authors.forename: L
authors.initials: L
authors.lastname: Gottschalk
authors.forename: F
authors.initials: F
authors.lastname: Lottspeich
authors.forename: H
authors.initials: H
authors.lastname: Scheer
mesh_terms: D000595:Amino Acid Sequence; D002499:Centrifugation, Density Gradient; D002942:Circular Dichroism; D000458:Cyanobacteria / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification; D045524:Phycobilisomes; D010798:Phycocyanin / Q000737:chemistry* / Q000302:isolation & purification; D011487:Protein Conformation; D013050:Spectrometry, Fluorescence
chemical_list: D046911:Macromolecular Substances; D010446:Peptide Fragments; D045524:Phycobilisomes; C002497:allophycocyanin; D010798:Phycocyanin