title: Reassembly of an integral oligomeric membrane protein OmpF porin in n-octyl beta-D: -glucopyranoside-lipids mixtures.
abstract: The denatured monomers of an integral membrane protein OmpF porin were refolded and reassembled into its sodium dodecyl sulfate-resistant trimer in mixtures of n-octyl beta-D: -glucopyranoside and lipids. Effective reassembly was observed with a yield of 60-70% when the denatured monomers (0.1 mg/mL) were solubilized at 25 degrees C for 24 h in a refolding medium (pH 6.9) containing 7 mg/mL n-octyl beta-D: -glucopyranoside, 1 mg/mL sodium dodecyl sulfate and 2-2.5 mg/mL soybean asolectin. The reassembled species was characterized in the presence of sodium dodecyl sulfate by physicochemical methods. Low-angle laser light scattering measurements revealed that the molecular weight of the reassembled species is 115,000 +/- 3,500 which corresponds to that of the trimer of this protein. Circular dichroism spectra suggested that the reassembled species is composed of the same beta-structure as the native one. Synchrotron radiation small-angle X-ray scattering measurements confirmed that the reassembled species is a trimer that has the same compactness as the native one.
authors.affiliation: National Food Research Institute, Kannondai 2-1-12, Tsukuba, Ibaraki, 305-8642, Japan. yasuw@affrc.go.jp
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Yoji
authors.initials: Y
authors.lastname: Inoko
mesh_terms: D055598:Chemical Phenomena; D002942:Circular Dichroism; D005960:Glucosides / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008027:Light; D010743:Phospholipids / Q000737:chemistry; D018272:Porins / Q000737:chemistry* / Q000378:metabolism; D017510:Protein Folding; D055503:Protein Multimerization; D053838:Scattering, Small Angle; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D005960:Glucosides; C109237:OmpF protein; D010743:Phospholipids; D018272:Porins; C018619:octyl-beta-D-glucoside; D012967:Sodium Dodecyl Sulfate