Beta Brainstorming Yi Jin & John

1 Biological Counter Aim Synthetic biology circuit that: senses an event counts how many times the event has occurred reports this value Application monitoring cellular activity

Previous work: Pam Silver lab Synthesized bio circuit to count the number of times cells have decided age 0 : red age 1 : cyan age 2 : yellow

Proposed central component Red pigment expressed as cyclin goes ‘high’ for first time ….. and stays high ….. until cyclin goes high second time Then presence of both pigment gene being expressed and cyclin at same time produces inhibitor of red pigment production Circuit then cycles Basically a ‘divide-by-two’ circuit

Proposed central component This circuit will turn red every other time cyclin goes ‘high’ Expand by then using expression of red signal as new ‘cyclin’ that expresses green etc For n colours can count up to 2 n

2 Bacterial Sundial Aim sundial that records, via photoactivated bacteria, the intensity of the sun coded against time via sundial like construction record UV and PAR levels and possibly other variables,eg temperature, as function of time these other variables would only be recorded if UV OR PAR present output via reporter pigments Application primarily educational

requirements gene expression under influence of UV and PAR genetic logic : if [(UV OR PAR) AND T] reporter – use pigments (as for Kandinsky) so direct read out (by eye) need bacteria evenly spatially distributed and ‘active’ (in appropriate growth phase) for around 8 hours large sensitivity range

3 Reaction-Diffusion in Animals Investigate the reaction-diffusion system in producing complex patterns in E.coli dishes Would it be possible to demonstrate or prove stripes / spots formation on the hides of animals? Would have cool application potential Individually patterned T-shirts! Personalized jewellery

4 Bacterial Colour Photography The original work by U of Texas, 2004

Bacterial Colour Photography (cont’d) Extends black-and-white to colour photography Engineer E. coli which is able to detect light in terms of three principle colours - red, blue and green

Bacterial Colour Photography (cont’d) Detection can be done by: Red light: Cph8 Green light: bacteriorhodopsin Blue light: Nph1 (from Arabidopsis) It has been found that E. coli is sensitive to blue light natively, however chromophore remains to be discovered

Bacterial Colour Photography (cont’d) Bacteria can then produce pigments of concentrations proportional to the incident light Red: Carotenoids Blue: Tetrapyrroles (yet to find good paper), X-gal, pyacyanin (might not be a good idea as it has antibiotic properties) Green: Tetrapyrroles, chlorophyll(?) Why pigments, not fluorescent proteins? Visible under normal lighting conditions Doesn't require special excitation wavelength to see emission wavelength

Bacterial Colour Photography (cont’d) Possible extensions / diversions Bacterial TV Find a way to destroy the pigments produced after a certain timeframe Possible to produce animated pictures on the dish by growing the bacteria in changing light conditions Palette of E. coli pigment colours Parts that can be integrated into devices to produce pigments when the part receives an input Would prove to be useful to future teams if they need coloured bacteria!