"
Team:Tsinghua-E
From 2013.igem.org
The Concept
Our team aimed at creating novel fast and irrational microbial cell factory by simulating natural Darwinian evolution process.
Home
FRED is our Functional, Robust Electrochemical Detector. FRED is responsible for detecting and measuring naphthenic acids (NAs) and is able to produce an electrochemical signal that can be measured. FRED can be used to measure toxins in tailings pond samples within minutes.
OSCAR
OSCAR is our Optimized System for Carboxylic Acid Remediation. OSCAR is responsible for converting toxins such as catechol and naphthenic acids into hydrocarbons. OSCAR is also capable of removing nitrogen and sulfur groups to further purify the hydrocarbons produced. Click on OSCAR to learn more!
Decarboxylation
In order to convert tailings pond toxins fully into hydrocarbons, we need to remove carboxylic acid groups. We are using the PetroBrick, from the University of Washington's 2011 iGEM team, to cleave off carboxylic acids to produce hydrocarbons. Click here to learn more!
Catechol Degradation
Catechol is a common toxic compound found in tailings ponds. We looked into giving OSCAR the ability to degrade catechol, which would also cleave ring structures of toxins.
Flux-Variability Analysis
We wanted to optimize OSCAR's output of hydrocarbons, so we computationally modelled how we can add particular metabolites to the growth media to increase hydrocarbon output. Click here to see what we found out!
Catechol Degradation
Catechol is a common toxic compound found in tailings ponds. We looked into giving OSCAR the ability to degrade catechol, which would also cleave ring structures of toxins.
Title and Abstract
| Darwinian evolution for microbial cell factory: |
| in vivo evolution engineering towards tryptophan-overproduction superbug |
| Darwinian evolution shows great power in creating incredible biological function in amazing speed. Inspired by this, our team aimed at creating novel fast and irrational microbial cell factory by simulating natural Darwinian evolution process. With tryptophan as target product, a novel tryptophan biosensor utilizing translating ribosome mechanism was firstly developed as the foundation for tryptophan productivity and selection pressure switch module. |
| We further constructed this tryptophan overproduction selection gene circuit coupling with in vivo mutation machine (mutator gene of mutD). By fine-tuning the selection conditions, our selection circuit showed good tryptophan dependent growth property, which provides the foundation for further evolution. As a preliminary result of this project,we successfully evolved an ancestor with zero productivity to a high-tryptophan producer only after several rounds of evolution. |
 |
