title: Expression and subcellular location of native and mutant hTNF alpha proteins in Escherichia coli.
abstract: Several mutant hTNF alpha genes were constructed by deletion and stepwise reconstitution of regions coding for C-terminal sequences. The mutant hTNF alpha proteins behaved differently from native hTNF alpha when expressed in Escherichia coli. They were either sensitive to proteolytic degradation or formed insoluble aggregates depending on the strains and conditions used for expression. By contrast, native hTNF alpha was always present in a soluble form and had a tendency to associate with the cytoplasmic membrane. It was even transported to the periplasmic space in E. coli as shown by both cell fractionation and immunoelectron microscopy. The different behaviour of mutant hTNF alpha proteins probably results from a disturbance of protein folding.
authors.affiliation: Institut für Mikrobiologie und experimentelle Therapie Jena, F.R.G.
authors.forename: K
authors.initials: K
authors.lastname: Gase
authors.forename: B
authors.initials: B
authors.lastname: Wagner
authors.forename: M
authors.initials: M
authors.lastname: Wagner
authors.forename: L
authors.initials: L
authors.lastname: Wollweber
authors.forename: D
authors.initials: D
authors.lastname: Behnke
mesh_terms: D000595:Amino Acid Sequence; D004252:DNA Mutational Analysis; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D007150:Immunohistochemistry; D016253:Microscopy, Immunoelectron; D008969:Molecular Sequence Data; D009154:Mutation; D011994:Recombinant Proteins; D013347:Subcellular Fractions / Q000737:chemistry; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha