Streptavidin was expressed on the outer membrane of E. coli as a recombinant fusion protein with an autotransporter domain called AIDA-I (adhesin involved in diffuse adherence) using autodisplay technology. The autodisplay of streptavidin was confirmed by SDS-PAGE of the outer membrane proteins, and the number of autodisplayed streptavidin molecules on a single E. coli cell was evaluated with densitometric analysis. The biotin-binding activity of the autodisplayed streptavidin was estimated after treatment with fluorescently labeled biotin by fluorescence microscopy and flow cytometry. The biotin-binding activity of the E. coli with autodisplayed streptavidin was compared with the activity of streptavidin immobilized on magnetic beads. Finally, the outer membrane presenting autodisplayed streptavidin was isolated and layered on a 96-well microplate for an immunoassay.
Bibliographical noteFunding Information:
This research was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology ( 2009-0082188, 2009-0073809 , 2009-008-1529 , 2009-62890 , F01-2009-10124 and R15-2004-024-00000-0 ) and by the “Happy Tech” program ( 2010-0020772 and 2010-0020767 ).
All Science Journal Classification (ASJC) codes
- Applied Microbiology and Biotechnology