IGEM:Harvard/2009/Brainstorming

We have a lot of great ideas for a summer project! Please add new topics or elaborate on the topics listed below.

Colon Cancer

A modified benign enteric strain of bacteria such as lactobacillus or a therapeutic strain of E. coli (they exist) that is capable of binding to a cell surface receptor expressed on the majority of colo-rectal carcinomas (CD24 receptor). The problem would be to figure out a way to transduce the signal and obtain a suitable readout. This would function as a cell based "micro-bot" that could potentially replace or supplement colonoscopic procedures or be employed as an initial screen for colon cancers. Perhaps the strains could also be modified to attack the carcinoma in-situ as well.

• Issues: signal transduction is a challenge! Also, most bacterial receptors bind to small molecules, rather than proteins.

Optical Quorum Sensing

Idea: One strain of bacteria would produce light (under inducible promoter); a second strain of bacteria would sense the light and turn on a second signal.

• Many variations on this. For example, use fuel cell to make electricity; second strain of bacteria responds to electrical current by producing light, which is then sent to another strain...
• Issues: is the frequency of emitted light (by luciferase, for example) compatible with frequency of light sensed (by rhodopsin, for example)?
  • There are many rhodopsins that absorb at different wavelengths. (See research by Craig Venter)
  • Visit Woody Hasting's webpage for information about bioluminescent bacteria. http://www.mcb.harvard.edu/hastings/dino.html

Cellular camera

A "fast gated" cellular camera? Again, the input would be light and the output would be a...membrane depolarization? electron transport? Can this then be coupled to the CLED?

Cellular Light Emitting Diode

Building a "cellular light emitting diode" ( CLED?) that is rapidly responsive to voltage inputs. I've located a very recent paper that describes a fusion protein that so it seems doable. I don't know if it can work in any of the bacterial strains and the construct would have to be modified to create an official biobrick. I haven't looked through the list of biobricks to see if something similar exists, if not, it could also be a novel addition to the registry.This could perhaps be coupled to the previous year's microbial fuel cell as a power source. http://pubs.acs.org/doi/abs/10.1021/ja808669y

Fluorescent proteins

Check out the Brainbow to see fun and informative ways that fluorescent proteins have been used!

Making a battery

Recently Andrea Belcher's lab at MIT engineered a virus that can grow battery components (anode, cathode). Could this be done with bacteria?

Other ideas?

• A project involving extremeophiles or cryptobiosis.