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A Convenient and General Expression Platform for the Production of Secreted Proteins from Human Cells
Published on: July 31, 2012
A structurally informed autotransporter platform for efficient heterologous protein secretion and display
Wouter S P Jong1, Zora Soprova, Karin de Punder
1Section Molecular Microbiology, Department of Molecular Cell Biology, Faculty of Earth and Life Sciences, VU University, De Boelelaan 1085, 1081 HV, Amsterdam, The Netherlands. w.s.p.jong@vu.nl
Researchers engineered the Hemoglobin protease (Hbp) autotransporter (AT) platform for efficient secretion and surface display of heterologous proteins, showing potential for recombinant live vaccines and biotechnology.
Area of Science:
- Biochemistry
- Molecular Biology
- Bacterial Protein Secretion
Background:
- Autotransporter (AT) proteins are key secretion systems in Gram-negative bacteria.
- Limited structural data of ATs has hindered their biotechnological applications.
- Engineering the Escherichia coli Hbp AT offers a promising platform for protein secretion.
Purpose of the Study:
- To engineer the Hbp autotransporter for heterologous protein secretion and surface display.
- To utilize the Mycobacterium tuberculosis vaccine antigen ESAT6 as a model protein.
- To assess the platform's applicability for recombinant live vaccine development.
Main Methods:
- Structural insights from Hbp crystal structure guided engineering.
- Passenger domains of Hbp were replaced with ESAT6.
- Cleavage site interruption created cell-surface display variants.
- Tested applicability with an alternative AT, EspC.
- Demonstrated display in an attenuated Salmonella typhimurium strain.
Main Results:
- Engineered Hbp-ESAT6 chimeras were efficiently secreted.
- An intact β-stem was crucial for stability.
- Surface display variants showed efficient ESAT6 exposure.
- The platform demonstrated broad applicability with EspC.
- Successful display in Salmonella typhimurium indicates vaccine potential.
Conclusions:
- Developed the first structurally informed AT platform for protein secretion and display.
- The Hbp platform shows significant potential for recombinant live vaccines.
- This platform can be applied to various biotechnological applications requiring high-level protein secretion or display.
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