title: Gene fusion analysis of membrane protein topology: a direct comparison of alkaline phosphatase and beta-lactamase fusions.
abstract: To compare two approaches to analyzing membrane protein topology, a number of alkaline phosphatase fusions to membrane proteins were converted to beta-lactamase fusions. While some alkaline phosphatase fusions near the N terminus of cytoplasmic loops of membrane proteins have anomalously high levels of activity, the equivalent beta-lactamase fusions do not. This disparity may reflect differences in the folding of beta-lactamase and alkaline phosphatase in the cytoplasm.
authors.affiliation: Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: W A
authors.initials: WA
authors.lastname: Prinz
authors.forename: J
authors.initials: J
authors.lastname: Beckwith
mesh_terms: D000469:Alkaline Phosphatase / Q000737:chemistry / Q000235:genetics; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics; D002462:Cell Membrane; D003001:Cloning, Molecular; D029968:Escherichia coli Proteins; D058619:Maltose-Binding Proteins; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics; D026901:Membrane Transport Proteins / Q000737:chemistry / Q000235:genetics; D008969:Molecular Sequence Data; D009004:Monosaccharide Transport Proteins; D011487:Protein Conformation; D011993:Recombinant Fusion Proteins / Q000737:chemistry* / Q000235:genetics; D027981:Symporters; D001618:beta-Lactamases / Q000737:chemistry / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; C050221:LacY protein, E coli; D058619:Maltose-Binding Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009004:Monosaccharide Transport Proteins; D011993:Recombinant Fusion Proteins; D027981:Symporters; C021499:lactose permease; D000469:Alkaline Phosphatase; D001618:beta-Lactamases