title: N-terminus leader sequence of Shiga toxin (Stx) 1 is essential for production of active recombinant protein in E. coli.
abstract: Escherichia coli clones expressing recombinant shiga toxin (Stx1) and its derivatives Stx1-A and Stx1-B subunits were established to release the proteins into periplasmic space. The expression was examined by SDS-PAGE to visualize the subunits. The secreted assembled subunits were extracted with polymyxin B and assessed for biological activity. The results showed that the presence of N-terminus leader sequence of the gene is essential for assembly of the subunits to yield biologically active holotoxin (AB5). The absence of the leader sequence did not affect the expression of the subunits but did disrupt the holotoxin assembly.
authors.affiliation: Molecular Biology Unit, Pasteur Institute of Iran. manaoloomi@yahoo.com
authors.forename: Mana
authors.initials: M
authors.lastname: Oloomi
authors.forename: Saeid
authors.initials: S
authors.lastname: Bouzari
authors.forename: Mania
authors.initials: M
authors.lastname: Arshadi
mesh_terms: D000818:Animals; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D021382:Protein Sorting Signals; D020836:Protein Structure, Quaternary; D021122:Protein Subunits / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011817:Rabbits; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D022622:Shiga Toxin 1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D021382:Protein Sorting Signals; D021122:Protein Subunits; D011994:Recombinant Proteins; D022622:Shiga Toxin 1