Download Cell Surface Targeting (we`re actually trying it!)

Cell Surface Targeting
(we’re actually trying it!)
Lewis Hahn
Perry Tsai
June 26, 2006
Outline
• Expressing Streptavidin at the E. coli cell
surface
– Two display options
– Why it might work! (More about streptavidin)
• Creating a DNA-DNA interface with the
cell surface
– What others have done
– Our plans
Expressing Streptavidin at the
E. coli cell surface
Two display options
• GPI-anchor
• Beta autotransporter
GPI-anchor
• Jung et al. 1998
– expressed levansucrase (400 amino acids)
– Fused to C-terminus of Inp
Autodisplay
• Jose 1997 (and 1999,2000,2001,…)
• Beta autotransporter
• Originally used with AIDA-I (adhesininvolved-in-diffuse-adherence)
Autodisplay mechanism
(Jose 1996)
Why it might work
Creating a DNA-DNA interface with
the cell surface
Previous work
• Tahiri-Alaoui et al. 2002
RNA-RNA
“Adaptamer”
CopA-CopT
(Kolb 2000)
CopA-CopT
(Kolb 2000)
Many options
• To start: work in solution.
• New interfaces?
– Secondary structure design?
• New Targets?
Other targets
• Dwarakanath et al. 2002
– DNA Aptamer to LPS
Summary
• A lot of building blocks are already there
– Streptavidin fusion protein
• GPI anchor
• Beta-autotransporter
– DNA-DNA or RNA-RNA interface
• Adaptamer
• New interfaces, new aptamers
Major Question
Will people talk to us?