Advanced

Surface display of Salmonella epitopes in Escherichia coli and Staphylococcus carnosus

Nhan, Nguyen Thanh; Gonzalez de Valdivia, Ernesto LU ; Gustavsson, Martin; Hai, Truong Nam and Larsson, Gen (2011) In Microbial Cell Factories 10.
Abstract

BACKGROUND: Salmonella enterica serotype Enteritidis (SE) is considered to be one of the most potent pathogenic Salmonella serotypes causing food-borne disease in humans. Since a live bacterial vaccine based on surface display of antigens has many advantages over traditional vaccines, we have studied the surface display of the SE antigenic proteins, H:gm and SefA in Escherichia coli by the β-autotransporter system, AIDA. This procedure was compared to protein translocation in Staphylococcus carnosus, using a staphylococci hybrid vector earlier developed for surface display of other vaccine epitopes.

RESULTS: Both SefA and H:gm were translocated to the outer membrane in Escherichia coli. SefA was expressed to full length but H:gm... (More)

BACKGROUND: Salmonella enterica serotype Enteritidis (SE) is considered to be one of the most potent pathogenic Salmonella serotypes causing food-borne disease in humans. Since a live bacterial vaccine based on surface display of antigens has many advantages over traditional vaccines, we have studied the surface display of the SE antigenic proteins, H:gm and SefA in Escherichia coli by the β-autotransporter system, AIDA. This procedure was compared to protein translocation in Staphylococcus carnosus, using a staphylococci hybrid vector earlier developed for surface display of other vaccine epitopes.

RESULTS: Both SefA and H:gm were translocated to the outer membrane in Escherichia coli. SefA was expressed to full length but H:gm was shorter than expected, probably due to a proteolytic cleavage of the N-terminal during passage either through the periplasm or over the membrane. FACS analysis confirmed that SefA was facing the extracellular environment, but this could not be conclusively established for H:gm since the N-terminal detection tag (His6) was cleaved off. Polyclonal salmonella antibodies confirmed the sustained antibody-antigen binding towards both proteins. The surface expression data from Staphylococcus carnosus suggested that the H:gm and SefA proteins were transported to the cell wall since the detection marker was displayed by FACS analysis.

CONCLUSION: Apart from the accumulated knowledge and the existence of a wealth of equipment and techniques, the results indicate the selection of E. coli for further studies for surface expression of salmonella antigens. Surface expression of the full length protein facing the cell environment was positively proven by standard analysis, and the FACS signal comparison to expression in Staphylococcus carnosus shows that the distribution of the surface protein on each cell was comparatively very narrow in E. coli, the E. coli outer membrane molecules can serve as an adjuvant for the surface antigenic proteins and multimeric forms of the SefA protein were detected which would probably be positive for the realisation of a strong antigenic property. The detection of specific and similar proteolytic cleavage patterns for both the proteins provides a further starting point for the investigation and development of the Escherichia coli AIDA autotransporter efficiency.

(Less)
Please use this url to cite or link to this publication:
author
publishing date
type
Contribution to journal
publication status
published
keywords
Antigens, Bacterial, Bacterial Proteins, Cloning, Molecular, Epitopes, Escherichia coli, Gene Expression, Membrane Proteins, Protein Transport, Salmonella enterica, Staphylococcus, Journal Article, Research Support, Non-U.S. Gov't
in
Microbial Cell Factories
volume
10
publisher
BioMed Central
external identifiers
  • scopus:79953801229
ISSN
1475-2859
DOI
10.1186/1475-2859-10-22
language
English
LU publication?
no
id
4c963b8a-cfff-438a-8dc6-b670d78004ef
date added to LUP
2018-01-13 11:51:38
date last changed
2018-05-29 12:03:16
@article{4c963b8a-cfff-438a-8dc6-b670d78004ef,
  abstract     = {<p>BACKGROUND: Salmonella enterica serotype Enteritidis (SE) is considered to be one of the most potent pathogenic Salmonella serotypes causing food-borne disease in humans. Since a live bacterial vaccine based on surface display of antigens has many advantages over traditional vaccines, we have studied the surface display of the SE antigenic proteins, H:gm and SefA in Escherichia coli by the β-autotransporter system, AIDA. This procedure was compared to protein translocation in Staphylococcus carnosus, using a staphylococci hybrid vector earlier developed for surface display of other vaccine epitopes.</p><p>RESULTS: Both SefA and H:gm were translocated to the outer membrane in Escherichia coli. SefA was expressed to full length but H:gm was shorter than expected, probably due to a proteolytic cleavage of the N-terminal during passage either through the periplasm or over the membrane. FACS analysis confirmed that SefA was facing the extracellular environment, but this could not be conclusively established for H:gm since the N-terminal detection tag (His6) was cleaved off. Polyclonal salmonella antibodies confirmed the sustained antibody-antigen binding towards both proteins. The surface expression data from Staphylococcus carnosus suggested that the H:gm and SefA proteins were transported to the cell wall since the detection marker was displayed by FACS analysis.</p><p>CONCLUSION: Apart from the accumulated knowledge and the existence of a wealth of equipment and techniques, the results indicate the selection of E. coli for further studies for surface expression of salmonella antigens. Surface expression of the full length protein facing the cell environment was positively proven by standard analysis, and the FACS signal comparison to expression in Staphylococcus carnosus shows that the distribution of the surface protein on each cell was comparatively very narrow in E. coli, the E. coli outer membrane molecules can serve as an adjuvant for the surface antigenic proteins and multimeric forms of the SefA protein were detected which would probably be positive for the realisation of a strong antigenic property. The detection of specific and similar proteolytic cleavage patterns for both the proteins provides a further starting point for the investigation and development of the Escherichia coli AIDA autotransporter efficiency.</p>},
  articleno    = {22},
  author       = {Nhan, Nguyen Thanh and Gonzalez de Valdivia, Ernesto and Gustavsson, Martin and Hai, Truong Nam and Larsson, Gen},
  issn         = {1475-2859},
  keyword      = {Antigens, Bacterial,Bacterial Proteins,Cloning, Molecular,Epitopes,Escherichia coli,Gene Expression,Membrane Proteins,Protein Transport,Salmonella enterica,Staphylococcus,Journal Article,Research Support, Non-U.S. Gov't},
  language     = {eng},
  month        = {04},
  publisher    = {BioMed Central},
  series       = {Microbial Cell Factories},
  title        = {Surface display of Salmonella epitopes in Escherichia coli and Staphylococcus carnosus},
  url          = {http://dx.doi.org/10.1186/1475-2859-10-22},
  volume       = {10},
  year         = {2011},
}