Template:Imperial/09/Overview

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Growth
Growth
The cells are grown to a critical cell density, before the system is started. This allows the culture to reach a sufficient stage of growth before the triggering the cells to begin protein which can slow cell growth.
Module 1: Protein Production
Module 1: Protein Production
The first module is induced with IPTG and triggers the production of the protein of interest. As part of this project we have looked into two proteins and a peptide of interest.
Module 2: Encapsulation
Module 2: Encapsulation
This second module is where the bacterium, after having produced the peptide of interest, produces colanic acid thus creating a protecting layer around itself to shelter it from the acidity of the stomach.
Module 3: Genome deletion
Module 3: Genome deletion
Module 3 occurs after encapsulation of the bacterium containing the produced peptide of interest. This module has the purpose of making the bacterium non viable. It does so by over-expressing restriction enzymes which subsequently cleave the genomic DNA into small fragments. The bacterium is thus unable to produce any proteins and therefore unable to survive.
Chemoinduction
Chemoinduction
Module 1 is induced by the addition of a compound, IPTG. This allows the user to 'kickstart' the system once the culture has reached a sufficiently high cell density.
Autoinduction
Autoinduction
Module 2 is triggered by a switch to a secondary carbon source. When the initial preferential carbon source (glucose) is exhausted, the system will metabolise the secondary carbon source that is available. This switch triggers the promoter that controls the start of Module 2. By knowing the initial concentrations of each carbon source, this acts as a programmable time delay system for the activation of encapsulation.
Thermoinduction
Thermoinduction
Module 3 is initiated upon an increase in temperature. The system is initially grown at 28 degrees, at which point Module 3 is repressed. When the temperature is raised to 42 degrees, this repression is blocked, triggering the start of Module 3. This temperature sensitive system was chosen as after encapsulation chemical induction may be less effective due to limited diffusion.
Thermoinduction
Thermoinduction
Module 3 is initiated upon an increase in temperature. The system is initially grown at 28 degrees, at which point Module 3 is repressed. When the temperature is raised to 42 degrees, this repression is blocked, triggering the start of Module 3. This temperature sensitive system was chosen as after encapsulation chemical induction may be less effective due to limited diffusion.

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