title: Isolation and complete amino acid sequence of the beta- and alpha-polypeptides from the peripheral light-harvesting pigment-protein complex II of Rhodobacter sulfidophilus.
abstract: The peripheral light-harvesting bacteriochlorophyll-carotenoid-protein complex B800-850 (LHII) has been isolated from membranes of semi-aerobic dark-grown cells of Rhodobacter sulfidophilus strain W4. A reversed-phase HPLC system resolved one beta- and one alpha-polypeptide in the ratio 1:1. The material obtained was of high purity and suitable for direct microsequence analysis. The primary structures of the beta- and alpha-polypeptides have been determined. The beta-polypeptide consists of 51 amino acid residues, yielding a molecular mass of 5512 Da and having 64.7% hydrophobicity. The alpha-polypeptide consists of 52 amino acid residues, with a calculated molecular mass of 5661 Da and 75% hydrophobicity. The significance of uncommon structure motives with respect to the unusual spectroscopic characteristics of this light-harvesting complex is discussed.
authors.affiliation: Institut für Biologie II/Mikrobiologie, Universität Freiburg, Germany.
authors.forename: M H
authors.initials: MH
authors.lastname: Tadros
authors.forename: G E
authors.initials: GE
authors.lastname: Hagemann
authors.forename: E
authors.initials: E
authors.lastname: Katsiou
authors.forename: R
authors.initials: R
authors.lastname: Dierstein
authors.forename: E
authors.initials: E
authors.lastname: Schiltz
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D002462:Cell Membrane / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D045342:Light-Harvesting Protein Complexes; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000302:isolation & purification; D045322:Photosynthetic Reaction Center Complex Proteins / Q000737:chemistry* / Q000302:isolation & purification; D016992:Rhodobacter / Q000737:chemistry*; D017421:Sequence Analysis
chemical_list: D001426:Bacterial Proteins; D045342:Light-Harvesting Protein Complexes; D010446:Peptide Fragments; D045322:Photosynthetic Reaction Center Complex Proteins; C081485:light-harvesting protein complex II, Rhodobacter capsulatus