Expression of Shiga Toxin B Subunit at Cell Surface in E. coli K-12

• 作 者: 苏国富 Himanshu N.Brahmbhatt Kenneth N.Timmis
• 机 构: Institute of Biotechnology, Academy of Military Medical Sciences CPLA, Beijing 100850, PRC,National
• 出 处: Science in China,Ser.B
• 发表日期: 1993年11期
• 关键词: Shiga coli K-12 Toxin Shigella subunit vaccine cytoplasm residues plasmid expres

The three parts(Stx17B, Stx27B and StxB) of Shiga toxin B subunit have been fused into a cell surface exposed loop of the LamB protein at a BamH I site between residues 153 and 154. Western blotting revealed that the three parts of Shiga toxin B subunit could be expressed as the Lamb fusion proteins in E. coli. Indirect immunofluorescence and immunoelectron microscopy analyses showed fusion proteins LamB/Stx17B and LamB/Stx27B could be expressed at cell surface in E. coli, but fusion protein LamB/StxB could not be expressed at cell surface; it was aggregated in cytoplasm and was toxic to host. This expression system provided a new way to construct an oral live vaccine against Shigella dysenteriae 1.

The three parts (Stx17B, Stx27B and StxB) of Shiga toxin B subunit have been fused into a cell surface exposed loop of the LamB protein at a BamH I site between residues 153 and 154. Western blotting revealed that the three parts of Shiga toxin B subunit could be expressed as the Lamb fusion proteins in E. coli. Indirect immunofluorescence and immunoelectron microscopy analysis showed fusion proteins LamB / Stx17B and LamB / Stx27B could be be at at cell surface in E. coli, but fusion protein LamB / StxB could not be expressed at cell surface; it was aggregated in cytoplasm and was toxic to host. This expression system provided a new way to construct an oral live vaccine against Shigella dysenteriae 1.