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Team:Edinburgh
From 2011.igem.org
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| - | A biorefinery is a special type of refinery in which biomass, such as plant <span class="hardword" id="cellulose">cellulose</span>, is converted by microorganisms into useful products. Edinburgh's 2011 iGEM project is a feasibility study into the creation of biorefineries using <span class="hardword" id="ec">E. coli</span>, the workhorse of synthetic biology, and whether biorefineries can be improved by arranging for the different enzymes involved to be in close proximity to each other. | + | A biorefinery is a special type of refinery in which biomass, such as plant <span class="hardword" id="cellulose">cellulose</span>, is converted by microorganisms into useful products. Edinburgh's 2011 iGEM project is a feasibility study into the creation of biorefineries using <span class="hardword" id="ec">E. coli</span>, the workhorse of synthetic biology, and whether biorefineries can be improved by arranging for the different enzymes involved to be in close proximity to each other, so as to create <span class="hardword" id="synergy">synergy</span> between them. |
==Synergy== | ==Synergy== | ||
| - | In many applications, several enzymes are needed to produce the desired product. And it is often the case that these enzymes work | + | In many applications, several enzymes are needed to produce the desired product. And it is often the case that these enzymes work synergistically; meaning their efficiency is increased if they are in close proximity. |
Last year, [https://2010.igem.org/Team:Slovenia Slovenia] found a way to achieve synergy in the periplasm. This year, Edinburgh is investigating whether such synergy can be achieved outside the cell. | Last year, [https://2010.igem.org/Team:Slovenia Slovenia] found a way to achieve synergy in the periplasm. This year, Edinburgh is investigating whether such synergy can be achieved outside the cell. | ||
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We will attempt to create microscopic <span class="hardword" id="bioreactor">bioreactors</span>, which we define as scaffolds holding various enzymes which carry out reactions in the extracellular environment. Our hope is that, by combining the activity of multiple enzymes in a small space, high efficiency will be achieved. Two different systems are being investigated. | We will attempt to create microscopic <span class="hardword" id="bioreactor">bioreactors</span>, which we define as scaffolds holding various enzymes which carry out reactions in the extracellular environment. Our hope is that, by combining the activity of multiple enzymes in a small space, high efficiency will be achieved. Two different systems are being investigated. | ||
| - | ==Cell surface display== | + | ===Cell surface display=== |
The simplest system uses ''E. coli'' bacteria as the scaffold. Each bacterium generates several enzymes and displays them on its outer membrane. If sufficiently high numbers are present on each cell, the synergystic effect should kick in. | The simplest system uses ''E. coli'' bacteria as the scaffold. Each bacterium generates several enzymes and displays them on its outer membrane. If sufficiently high numbers are present on each cell, the synergystic effect should kick in. | ||
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[http://www.sciencedirect.com/science/article/pii/S016777991000199X Van Bloois ''et al'' (2011)] speak highly of INP, and claim that it can be displayed at a copy number of around 100,000 copies per cell without affecting viability. | [http://www.sciencedirect.com/science/article/pii/S016777991000199X Van Bloois ''et al'' (2011)] speak highly of INP, and claim that it can be displayed at a copy number of around 100,000 copies per cell without affecting viability. | ||
| - | ==Phage display== | + | ===Phage display=== |
A more radical proposal involves use <span class="hardword" id="m13">M13</span> <span class="hardword" id="phage">phage</span> as the scaffold, and attaching enzymes by phage-display techniques to the <span class="hardword" id="p8">pVIII</span> coat protein. | A more radical proposal involves use <span class="hardword" id="m13">M13</span> <span class="hardword" id="phage">phage</span> as the scaffold, and attaching enzymes by phage-display techniques to the <span class="hardword" id="p8">pVIII</span> coat protein. | ||
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==Biorefinery== | ==Biorefinery== | ||
| - | + | We believe that it is insufficient to ask whether the low-level biological challenges can be overcome. There are also engineering problems to consider, and so we have worked on an actual design for a biorefinery. | |
| - | + | More than this, political and social implications of biorefineries demand our attention. We must ask not only whether we can do something, but also whether we should. Answering this question is one of the most important parts of our feasibility study. | |
| - | + | ==References== | |
* Van Bloois E, Winter RT, Kolmar H, Fraaije MW (2011) [http://www.sciencedirect.com/science/article/pii/S016777991000199X Decorating microbes: surface display of proteins on ''Escherichia coli'']. ''Trends in Biotechnology'' '''29'''(2): 79-86 (doi: 10.1016/j.tibtech.2010.11.003). | * Van Bloois E, Winter RT, Kolmar H, Fraaije MW (2011) [http://www.sciencedirect.com/science/article/pii/S016777991000199X Decorating microbes: surface display of proteins on ''Escherichia coli'']. ''Trends in Biotechnology'' '''29'''(2): 79-86 (doi: 10.1016/j.tibtech.2010.11.003). | ||
Revision as of 13:13, 19 August 2011
A biorefinery is a special type of refinery in which biomass, such as plant cellulose, is converted by microorganisms into useful products. Edinburgh's 2011 iGEM project is a feasibility study into the creation of biorefineries using E. coli, the workhorse of synthetic biology, and whether biorefineries can be improved by arranging for the different enzymes involved to be in close proximity to each other, so as to create synergy between them.
Synergy
In many applications, several enzymes are needed to produce the desired product. And it is often the case that these enzymes work synergistically; meaning their efficiency is increased if they are in close proximity.
Last year, Slovenia found a way to achieve synergy in the periplasm. This year, Edinburgh is investigating whether such synergy can be achieved outside the cell.
We will attempt to create microscopic bioreactors, which we define as scaffolds holding various enzymes which carry out reactions in the extracellular environment. Our hope is that, by combining the activity of multiple enzymes in a small space, high efficiency will be achieved. Two different systems are being investigated.
Cell surface display
The simplest system uses E. coli bacteria as the scaffold. Each bacterium generates several enzymes and displays them on its outer membrane. If sufficiently high numbers are present on each cell, the synergystic effect should kick in.
To achieve a high expression level, we will attempt to use ice nucleation protein as a carrier for enzymes; Van Bloois et al (2011) speak highly of INP, and claim that it can be displayed at a copy number of around 100,000 copies per cell without affecting viability.
Phage display
A more radical proposal involves use M13 phage as the scaffold, and attaching enzymes by phage-display techniques to the pVIII coat protein.
Biorefinery
We believe that it is insufficient to ask whether the low-level biological challenges can be overcome. There are also engineering problems to consider, and so we have worked on an actual design for a biorefinery.
More than this, political and social implications of biorefineries demand our attention. We must ask not only whether we can do something, but also whether we should. Answering this question is one of the most important parts of our feasibility study.
References
- Van Bloois E, Winter RT, Kolmar H, Fraaije MW (2011) Decorating microbes: surface display of proteins on Escherichia coli. Trends in Biotechnology 29(2): 79-86 (doi: 10.1016/j.tibtech.2010.11.003).
