title: Molecular size determination of a membrane protein in surfactants by light scattering.
abstract: The molecular size of an outer surface protein from the photosynthetic bacterium Chlorobium tepidum was studied by dynamic light scattering (DLS) and HPLC gel filtration. For that purpose, the membrane protein was isolated and studied in four different nonionic surfactants, namely t-octylphenoxypolyethenoxyethanol (Triton X-100), (methyl-6-O-(N)-heptyl-carbamoyl)-alpha-D-glucopyranoside (Hecameg), dodecyl-beta-D-maltoside (DDM) and n-octyl-oligo-oxyethylene (Octyl-POE). The protein was isolated by solubilization of the membranes with Triton X-100. The final purification step was a gel filtration, which was also used for surfactant exchange. Light scattering reveals the simultaneous presence of particles of different sizes in the 3-6 and 20-110 nm range, respectively. The smaller size is related to the hydrodynamic radius of the individual protein/surfactant complexes, whereas the larger size is associated with the presence of complex aggregates.
authors.affiliation: Division of Biochemistry, Department of Chemistry, University of Crete, Heralilion, Greece.
authors.forename: Michalis
authors.initials: M
authors.lastname: Aivaliotis
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Samolis
authors.forename: Elefteria
authors.initials: E
authors.lastname: Neofotistou
authors.forename: Herve
authors.initials: H
authors.lastname: Remigy
authors.forename: Apostolos K
authors.initials: AK
authors.lastname: Rizos
authors.forename: Georgios
authors.initials: G
authors.lastname: Tsiotis
mesh_terms: D019414:Chlorobi / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D008027:Light; D008565:Membrane Proteins / Q000737:chemistry*; D013501:Surface-Active Agents
chemical_list: D008565:Membrane Proteins; D013501:Surface-Active Agents