Difference between revisions of "Part:BBa K3394006"

Latest revision as of 17:04, 25 October 2020

AIDA-I auto-display system

Since cellulose cannot cross the membrane, we engineered E. coli to express the cellulolytic complex on its surface through AIDA-I auto-display system.

The AIDA-I auto-display system we chose, utilizes the translocation mechanism of passenger proteins across the outer membrane through a C-terminal beta-barrel and its preceding linking region. We planned to use JK321 E. coli strain which is a DsbA-negative mutant strain of E. coli that facilitates the autodisplay of passenger proteins and contains the AIDA-I auto display plasmid. The ompT-gene (Outer membrane protease T) in the DsbA-negative strain was mutated in order to obtain a stable surface display of the recombinant passenger proteins.

Figure 1: AIDA-I auto-display system. Structure of the polyprotein precursor and the secretion mechanism of the autotransporter proteins (SP, signal peptide; IM, inner membrane; PP, periplasm; OM, outer membrane). source: Jose, J., & Meyer, T. F. (2007). The Autodisplay Story, from Discovery to Biotechnical and Biomedical Applications. Microbiology and Molecular Biology Reviews, 71(4), 600–619.

In figure 1, we can see the structure of the polyprotein precursor. By the use of a typical signal peptide (SP), a precursor protein is transported across the inner membrane. After arrival at the periplasm, the C-terminal part of the precursor folds as a porin-like structure, a so-called beta-barrel within the outer membrane, and the passenger proteins are transmitted to the cell surface.

Sequence and Features