IGEM:MIT/2006/Blurb

This summer, MIT's iGEM 2006 team is developing bacteria that smell pleasant. We have inserted several genes into bacterial genomes to make the cells produce a wintergreen and/or a banana scent. Scents can act as natural biological tags and have many extended applications. By attaching the scent tag to a case-sensitive promoter, we can engineer a cellular system to report on environmental conditions. Also, since E. coli naturally produce a fecal smelling compound, we feel that engineering our system will be useful to scientists worldwide as it will make lab work with E. coli bacteria a little less painful. Other bacteria are responsible for producing human odor problems in the mouth, armpits, and feet. By implementing our system in these foul smelling bacteria, we could potentially develop bacterial deoderant. In addition, we could implement our system in yeast, thereby producing new flavors and scents in bread and beer. Perfuming bacterial biofilters are yet another feasible industrial application of our project.

Members

The MIT iGEM team consists of 5 students working fulltime during summer 2006 on engineering a biological system. In addition, we have 5 graduate student advisors and 2 faculty advisors.

From left to right: Stephen Payne, Boyuan Zhu, Tom Knight, Reshma Shetty, Andre Green, Samantha Sutton, Veena Venkatachalam, Jason Kelly, Austin Che, Barry Canton and Kate Broadbent. Not shown but there in spirit: Drew Endy. Photo courtesy of Heather Keller, MIT

Students

• Kate Broadbent
• Andre Green
• Stephen Payne
• Veena Venkatachalam
• Boyuan Zhu

Email us: team AT igem.mit.edu

Advisors

• Barry Canton
• Austin Che
• Drew Endy
• Jason Kelly
• Tom Knight
• Reshma Shetty
• Samantha Sutton

Email us: igem AT igem.mit.edu

Project description

This summer, MIT's iGEM 2006 team engineered Escherichia coli to produce a wintergreen scent during exponential phase and a banana scent during stationary phase using only endogenous metabolites. Thus, our project demonstrates that

1. It is indeed possible to design, build and test a synthetic biological system over the course of a summer.
2. Biosynthetic devices that produce scented compounds can be successfully engineered in E. coli.
3. Biosynthetic devices can be purposefully regulated via transcription based control devices.

Motivations

Our project focused on engineering Escherichia coli to produce different compounds that smell fragrant. Since scents can both act as natural reporters and have a diverse array of applications, they represent a promising but thus far unexplored area of synthetic biology.

Future applications of this work that we envision include ...

• Improving the workplace environment for microbiologists working with Escherichia coli since E. coli produce a natural foul scent.
• Porting our system to bacterial species involved in bioremediation.
• Implementing our system in bacteria responsible for bad human odor in the mouth, armpits and feet.

Contributions

Devices

1. A biosynthetic device that converts salicylic acid to methyl salicylate (or wintergreen).
2. A biosynthetic device that converts isoamyl alcohol to isoamyl acetate (or banana smell).
3. A PoPS source that is only active during stationary phase.
4. A PoPS source that is only active during exponential phase.

Systems

1. Escherichia coli capable of producing a wintergreen scent autonomously (without addition of any precursors).
2. E. coli capable of producing a banana scent autonomously (without addition of any precursors).

Future work

coming soon ...

Team photos

• File:MIT IGEM2006.jpg
• Photo courtesy of Professor Daisuke Umeno, Chiba University.

  Photo courtesy of Professor Daisuke Umeno, Chiba University.

• Image courtesy of Professor Daisuke Umeno, Chiba University.

  Image courtesy of Professor Daisuke Umeno, Chiba University.

• 

  Photo courtesy of Heather Keller, MIT.

• 

  Photo courtesy of Heather Keller, MIT.

• 

  Photo courtesy of Heather Keller, MIT.

Poster topics

Eau d’e coli

Why

• engineered bacterial scents because they are tangible and practical. We had a vision and we were confident that we could make it a reality in just one summer!
• We could focus on creativity and control. Nobody has ever attempted to create a modular autonomous scent system as the backbone for future application.
• coolness factor! our bacteria smell delicious!

What

• We have successfully reached our goal of developing bacteria that smell pleasant. We began by first isolating genes from s. cerivisae (baker’s yeast), petunia hybrida (a plant species), and pseudomonas fluorescens (a harmless soil bacterium). We then built our system by inserting these genes into the E. coli genome. The result? our E. coli cells produce a wintergreen scent while in the exponential growth phase (first 7 hours of growth), followed by a banana scent when they reach the stationary growth phase. Our most complex system features completely autonomous scent production with an inverter device controlling the on/off switch between the mint and the banana scent reporters.

Applications

• E. coli bacteria naturally produce a fecal smelling compound called indole. Our system features, in addition to mint and banana scent output, the added bonus of a cell chassis incapable of producing indole. We feel that our engineered cells may prove useful to scientists worldwide, as they make lab work with E. coli bacteria a little less painful!

• Portability and implementation: Bacteria are responsible for producing human odor problems in the mouth, armpits, and feet. By implementing our system in these foul smelling bacteria, we could potentially develop perfuming bacterial deoderant and/or chewing gum. In addition, we could implement our system in yeast, thereby producing new flavors and scents in bread and beer. Perfuming bacterial biofilters are yet another feasible industrial application of our project.

Alternative

(by Kate, Austin, Reshma)

Motivations

• Bacterial scents are natural tags
• Scents are unexplored in synthetic biology.
• potential future applications of this work are

Future work

1. boosting production of precursor compounds to enahnce smell
2. characterizing scent compounds via GC
3. port the BSGD to yeast
4. port the WGD to pseudomonas

Poster edits

1. Top/Title:
   • we need to list undergrad+grad+faculty names: suggestion is to fade

out the perfume bottle in the top right corner and to write names over top in black

1. Left 1/3:
   • left corner top: rename this section as "motivations" (=combo of

what/why/applications). we can put a few simple bullets similar to what is on wiki "alternative"

1. • left side middle: change to "key part contributions" -- so rather

than listing every intermediate part/etc. in an overwhelming fashion, we can just show our 5 main enzyme genes plus osmY in a chart:

1. • • "biobrick name function source:

species + reference #"

1. • left side bottom: "Characterization" --- need to simplify our graphs.

too many points/colors. we can either average our data or show one run w/o duplicates. also, the font on the key should be larger.

1. Center/Right 2/3:
   • add title: "system"
   • center/top = the diagram we used in past presentation graphing our

ideal goal of wintergreen and then banana smell. this takes care of a lot of words

1. • right/top = black box picture. lets make the boxes all black instead

of grayish. also, we need to draw an arrow connecting the enzyme to the line between boxes. we should get rid of the media box. also right out generator instead of GD. and we need to put the chemical output from the boxes (and mint + banana icon if possible)

1. • center/right middle section: 4 device pictures. we should get rid of

all the text below pictures for poster. edit out the trunc and full part on the osmY parts. also the enzyme between IAGD and BGD changes. i know it is the same technically, but we should be consistent and stick with isoamyl alcohol in both places.

1. • bottom center/right: get rid of registry snapshot and team photo.

replace with a short "future work" section, and a small font acknowledgements/references section.