title: Refolded dengue virus type 2 NS1 protein expressed in Escherichia coli preserves structural and immunological properties of the native protein.
abstract: The dengue virus NS1 protein has been shown to be a protective antigen under different experimental conditions but the recombinant protein produced in bacterial expression systems is usually not soluble and loses structural and immunological features of the native viral protein. In the present study, experimental conditions leading to purification and refolding of the recombinant dengue virus type 2 (DENV-2) NS1 protein expressed in Escherichia coli are described. The refolded recombinant protein was recovered as heat-stable soluble dimers with preserved structural features, as demonstrated by spectroscopic methods. In addition, antibodies against epitopes of the NS1 protein expressed in eukaryotic cells recognized the refolded protein expressed in E. coli but not the denatured form or the same protein submitted to a different refolding condition. Collectively, the results demonstrate that the recombinant NS1 protein preserved important conformation and antigenic determinants of the native virus protein and represents a valuable reagent either for the development of vaccines or for diagnostic methods.
authors.affiliation: Department of Microbiology, University of São Paulo, Brazil.
authors.forename: Jaime Henrique
authors.initials: JH
authors.lastname: Amorim
authors.forename: Bruna F M M
authors.initials: BF
authors.lastname: Porchia
authors.forename: Andrea
authors.initials: A
authors.lastname: Balan
authors.forename: Rafael C M
authors.initials: RC
authors.lastname: Cavalcante
authors.forename: Simone Morais
authors.initials: SM
authors.lastname: da Costa
authors.forename: Ada Maria
authors.initials: AM
authors.lastname: de Barcelos Alves
authors.forename: Luís Carlos
authors.initials: LC
authors.lastname: de Souza Ferreira
mesh_terms: D000914:Antibodies, Viral / Q000276:immunology; D003716:Dengue Virus / Q000737:chemistry* / Q000235:genetics / Q000276:immunology*; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression; D006801:Humans; D017510:Protein Folding; D055503:Protein Multimerization; D055550:Protein Stability; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D013057:Spectrum Analysis; D013696:Temperature; D017361:Viral Nonstructural Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; C079340:NS1 protein, Dengue virus type 2; D011994:Recombinant Proteins; D017361:Viral Nonstructural Proteins