Transcript Projects - iGEM 2007

Goal:
Duke
faculty
NC
genetically
Jamboree
months
to
School
University
have
advisors
of
fun…
engineered
Science
…and
undergraduates
appearances
build
and
designs
some
Math
really
High Schoolers
cool stuff!
Meet the Duke Team
in front of the camera:
Jingdong Tian, Nicholas Tang, Cory Li, Lisa Zhang,
Yaijing Gao, Eric Josephs, Faisal Reza
back in the lab:
Aamir Husain, Bruce Donald, Lingchong You, Fan Yuan
Synthetic Controls in
Bacterial Systems
Projects
• Electrical Field-Modulated Transcription
Factors
• Light-Based Intercellular Communications
• Photon-Assisted Fuel Cell
• Chemical Pathway-Perturbed Bioplastics
Can we control the activity of a
transcription factor using electric fields?
Electrical field-modulated
transcription factors
Darst, et al. Molecular Cell. 2004
Electrical field-modulated
transcription factors
• WT:
STKKKP
• Mut3: XXXKKP
• Mut5: XXXXXP
Beamer, et al. Science. 1994
Electrical field-modulated
transcription factors
Electrical field-modulated
transcription factors
•
•
•
•
IPTG induces production of λcI
Binds to DNA = RED
Doesn’t bind to DNA = YELLOW/GREEN
No plasmid = NO FLUORESCENCE
Screen
Electrical field-modulated
transcription factors
Electrical field-modulated
transcription factors
Selected group of colonies at 45C
Initial
2 hours
3.5 hours
Electrical field-modulated
transcription factors
Electrical field-modulated
transcription factors
Electrical field-modulated
transcription factors
• Results:
– Created a screen in order to determine
whether mutant transcription factors are
bound or unbound.
– Demonstrated the efficacy of the screen
with by finding a heat-activated
transcription factor
– Currently deeply involved in searching
for electric field- activated transcription
factors.
Can fluorescence in one group of bacteria
activate transcription factors in another
group?
Quorum Sensing
vs
Light
Light Sensitivity
100W Light
Few feet away
vs
Bacteria Fluorescence
Few nanometers away
Applications
• Cells can see each other
• Fastest diffusing and
degrading signal
• Highly sensitive reporter
Applications
• More complex
logic gates
Can E. coli with photon-activated proton
pumps extend the lifetime and power
output of a microbial fuel cell?
Photon-driven
Microbial Fuel Cell
• In microbial fuel
cells, a mediator
transport electrons
from a bacteria’s
metabolic pathway
to an anode.
• Unfortunately, this
also starves the
bacteria.
Photon-driven
Microbial Fuel Cell
• We worked with a
series of genes that
code for a lightactivated proton
pump.
• By using ‘solarpowered’ bacteria, we
aim to boost device
lifetime and efficiency.
• We are currently
analyzing the data
from the fuel cell.
Can we genetically regulate 3HB and 4HB
percent composition in a recombinant
bioplastic copolymers?
Chemical pathwayperturbed bioplastics
• 3HB and 4HB
copolymers form
biodegradable
plastics with
tunable properties.
Chemical pathwayperturbed bioplastics
• By modeling the
copolymer production,
we were able to
determine the most
effective and efficient
intermediate to
engineer
• We are in the process
of constructing a
circuit regulating the
thiolase enzyme used
in 3HB production.
Projects
Electric fieldmodulated
transcription
factors:
Light-based
intercellular
communications
Photon-driven
microbial fuel
cell:
Chemical
pathwayperturbed
bioplastics:
Take Home Message
• Constructed a circuit to test mutants for DNA
binding
• Identified a heat-activated transcription factor
Projects
Electric fieldmodulated
transcription
factors:
Take Home Message
• Constructed a circuit to test mutants for DNA
binding
• Identified a heat-activated transcription factor
Light-based
intercellular
• Verified the functionality of plasmids
communications
Photon-driven
microbial fuel
cell:
Chemical
pathwayperturbed
bioplastics:
Projects
Electric fieldmodulated
transcription
factors:
Take Home Message
• Constructed a circuit to test mutants for DNA
binding
• Identified a heat-activated transcription factor
Light-based
intercellular
• Verified the functionality of plasmids
communications
Photon-driven
• Designed and constructed a microbial fuel cell
microbial fuel
for light-powered bacteria
cell:
Chemical
pathwayperturbed
bioplastics:
Projects
Electric fieldmodulated
transcription
factors:
Take Home Message
• Constructed a circuit to test mutants for DNA
binding
• Identified a heat-activated transcription factor
Light-based
intercellular
• Verified the functionality of plasmids
communications
Photon-driven
• Designed and constructed a microbial fuel cell
microbial fuel
for light-powered bacteria
cell:
Chemical
pathwayperturbed
bioplastics:
• Determined the most efficient intermediate to
control plastic properties and optimize overall
plastic production.
Acknowledgements
• Jingdong Tian Ph.D.
• Faisal Reza M.S.
• Bruce Donald Ph.D.
• Fan Yuan Ph.D.
• Lingchong You Ph.D.