title: Refined crystal structure of phycoerythrin from Porphyridium cruentum at 0.23-nm resolution and localization of the gamma subunit.
abstract: The three-dimensional structure of the light-harvesting pigment-protein b-phycoerythrin from the red alga Porphyridium cruentum has been determined at 0.23-nm resolution. The b-phycoerythrin structure is very similar to the structure of B-phycoerythrin from Porphyridium sordidum. Besides three non-identical residues there are only small differences between b-phycoerythrin and B-phycoerythrin alpha and beta subunits, respectively. In the crystals b-phycoerythrin forms an (alpha beta)6 hexamer (molecular mass: 236 kDa), whereas B-phycoerythrin additionally contains a 30-kDa gamma subunit. The comparison of the b-phycoerythrin and B-phycoerythrin electron-density maps clearly reveals, that the gamma subunit is located inside the (alpha beta)6 aggregate.
authors.affiliation: Max-Planck-Institut für Biochemie, Martinsried, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Ficner
authors.forename: R
authors.initials: R
authors.lastname: Huber
mesh_terms: D018360:Crystallography, X-Ray; D010799:Phycoerythrin / Q000737:chemistry* / Q000302:isolation & purification; D011487:Protein Conformation; D000461:Rhodophyta / Q000737:chemistry*
chemical_list: D010799:Phycoerythrin