title: Purified cholera toxin B subunit from transgenic tobacco plants possesses authentic antigenicity.
abstract: Cholera toxin B subunit (CTB) mature protein was stably expressed in transgenic tobacco plants under the control of the CaMV 35S promoter and TMV Omega fragment. Fusion of the PR1b signal peptide coding sequence to the CTB mature protein gene increased the expression level by 24-fold. The tobacco-synthesized CTB (tCTB) was purified to homogeneity by a single step of immunoaffinity chromatography. The purified tCTB is predominantly in the form of pentamers with molecular weight identical to the native pentameric CTB, indicating that the PR1b-CTB fusion protein has been properly processed in tobacco cells. Furthermore, by immunodiffusion and immunoelectrophoresis, we have shown that the antigenicity of the purified tCTB is indistinguishable from that of the native CTB protein.
authors.affiliation: Laboratory of Plant Biotechnology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, P.R. China.
authors.forename: X G
authors.initials: XG
authors.lastname: Wang
authors.forename: G H
authors.initials: GH
authors.lastname: Zhang
authors.forename: C X
authors.initials: CX
authors.lastname: Liu
authors.forename: Y H
authors.initials: YH
authors.lastname: Zhang
authors.forename: C Z
authors.initials: CZ
authors.lastname: Xiao
authors.forename: R X
authors.initials: RX
authors.lastname: Fang
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D017796:Caulimovirus / Q000235:genetics; D002772:Cholera Toxin / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D018506:Gene Expression Regulation, Plant; D005813:Genes, Synthetic; D005822:Genetic Vectors / Q000235:genetics; D007106:Immune Sera; D007114:Immunization; D015151:Immunoblotting; D007122:Immunoelectrophoresis; D051379:Mice; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D011401:Promoter Regions, Genetic; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D014026:Nicotiana / Q000378:metabolism*; D014027:Tobacco Mosaic Virus / Q000235:genetics; D019076:Transgenes
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D007106:Immune Sera; D011993:Recombinant Fusion Proteins; D002772:Cholera Toxin