Related Experiment Video
Updated: Jun 21, 2026
Applying an Inducible Expression System to Study Interference of Bacterial Virulence Factors with Intracellular Signaling
Published on: June 25, 2015
Stable surface expression of a gene for Helicobacter pylori toxic porin protein with pBAD expression system
Zhixiang Peng1, Xi Wei, Zhengmei Lin
1Department of Endodontics, Guanghua College of Stomatology, Sun Yat-Sen University, Guangzhou, 510055, China. pengzhixiang@gmail.com
Abstract:
Helicobacter pylori (H. pylori) infection causes peptic and duodenal diseases in humans. Among a 32-protein family of outer membrane proteins, a porin-like protein, HopE, has been a subject of note, mainly for its conservative nature among H. pylori, and for its potential as a vaccine candidate. To achieve stable surface expression of this host cell-toxic protein, hopE gene was introduced into pBAD expression system. After induction with arabinose, all 15 randomly-chosen E. coli LMG 194 colonies from 3 successive passages could express HopE protein, while only 1 from 5 E. coli colonies that contained lac operon-regulated plasmid encoding hopE gene could express HopE. Indirect immunofluorescence confirmed the expression of HopE on E. coli cell surface.
Insights
Helicobacter pylori outer membrane protein HopE, a potential vaccine candidate, was successfully expressed on E. coli surfaces. The pBAD system demonstrated superior efficiency for HopE surface expression compared to the lac operon system.
Area of Science:
- Microbiology
- Molecular Biology
- Vaccinology
Background:
- Helicobacter pylori (H. pylori) infection is a primary cause of peptic and duodenal diseases.
- Outer membrane proteins (OMPs) of H. pylori are crucial for pathogenesis and potential vaccine targets.
- HopE, a conserved porin-like outer membrane protein, shows promise as a vaccine candidate.
Purpose of the Study:
- To achieve stable surface expression of the potentially host cell-toxic H. pylori outer membrane protein, HopE, in E. coli.
- To compare the efficacy of the pBAD and lac operon expression systems for HopE surface display.
Main Methods:
- The hopE gene was cloned into the pBAD and lac operon-regulated expression systems.
- Escherichia coli (E. coli) LMG 194 strains were transformed with the constructed plasmids.
- Protein expression was induced and confirmed using indirect immunofluorescence assays.
Main Results:
- All tested E. coli colonies transformed with the pBAD expression system successfully expressed HopE protein on their surface after arabinose induction.
- Only one out of five E. coli colonies transformed with the lac operon-regulated plasmid expressed HopE.
- Indirect immunofluorescence confirmed the surface localization of HopE in E. coli.
Conclusions:
- The pBAD expression system is highly efficient for achieving stable surface expression of H. pylori HopE in E. coli.
- HopE can be successfully displayed on the E. coli surface, supporting its development as a potential vaccine candidate.
More Related Videos
08:57Identification of Novel Genes Associated with Alginate Production in Pseudomonas aeruginosa Using Mini-himar1 Mariner Transposon-mediated Mutagenesis
Published on: March 10, 2014
09:14Modifying Baculovirus Expression Vectors to Produce Secreted Plant Proteins in Insect Cells
Published on: August 20, 2018
