We have reviewed our organisms and parts against the White List. All the parts and bacterial strains that we used are in the Risk Group 1
We have submitted to iGEM headquarters “About Our Lab” and “About Our Project” questionnaires by the June 26th deadline
We have submitted to iGEM headquarters the “Final Safety Form” by the August 28th deadline
About Safety
We, the UNITN iGEM Team want to follow high standards of safe and responsible biological engineering. Before entering the lab we attended mandatory on-line courses regarding lab safety with final tests. In particular we focused on the following topics:
- General considerations on risks and prevention
- Electrical Hazard
- Chemical Hazard
- Biological Hazard
- Compressed gasses and cryogenic liquids
We also attended the “Health and safety at the workplace” course, which is mandatory for all students and workers at the University of Trento.
Safe Project Design
Our solar microbial fuel cell is designed to be used by the public. We envision that our Solar pMFC will be implemented to allow people with no specific skills to operate it.
Our idea is to have a device that can be installed in your house and mimics a photovoltaic system. What is needed is just a good exposition to light, e.g. placing it on top of a roof.
Our MFC requires a growth media, our engineered bacteria and sunlight. In the laboratory we tested the system with LB or M9, however we envision that our system will be redesigned so that the bacteria can use organic waste from the house (i.e. kitchen waste containing sugars or other C sources). To minimize the amount of contaminated media we were thinking to implement the Solar pMFC with a circulating system equipped with a filter that allows to remove the bacteria from the media, while accumulating the bacteria in the filter. In this way the decontaminated media could be disposed directly in the plumbing of the house.
The exhausted bacteria accumulated in the filter could be routinely removed and discarded properly (not in the environment). Fresh bacteria could be added placing a new batch of bacteria in the system. We imagine a capsule, similar to espresso-capsule, that could be placed easily in the system when necessary. The life-span of the bacteria today it is a limit, although our Proteorhodopsin expressing bacteria should live significant longer, thus reducing the need of replacing them often.
Our Solar pMFC is better than existing technologies because:
- we know exactly the bacteria that are inside and generate electricity, thus reducing the biological hazard. We believe that using well characterized and controlled (i.e inducible) bacteria provides a better-working and safer device. This is an advantage respect to other MFCs.
- it uses sun light to be powered, thus reducing the consumption of electricity to operate it
- Thank to our circulating/filter system to decontaminate the media, we will reduce the amount of dirty waste to be disposed, thus making it better and safer for the environment
- It is better than photovoltaic systems on the market that are based on silicon. Silicon it is not a problem itself, however the production of silicon photovoltaic systems requires toxic chemicals (silicon tetrachloride, Sulphur Hexafluoride, heavy metals such cadmium and lead). Also, the disposal of large amount of silicon panels will become a problem one day for the environment
- Our pMFC will be cheap and thus be competitive on the market. The production cost of one solar pMFC to be used in the laboratory is around 250 $. This cost covers the expenses of the material
and the work to build a cell containing 1.7 L of media. This cost should be decreased at least by half if the MFC is built industrially. Alternatively in a no distant future we will be able to print MFCs at home with a 3D printer.
We estimated that today the cost of operation for 48 hours is:
17.00 $ of media. This cost should become zero if our bacterial strain become able to use alternative C sources, i.e. kitchen waste.
0.10 $ x for arabinose.
0.00 $ for sunlight
Therefore the operating cost should become close to zero.
Working Safely... with Parts
All the parts we used throughout the project are NOT toxic or dangerous for humans or the environment. We neither worked with proteins toxic themselves, nor we used enzymes that synthesize toxic molecules. In addition to basic parts from the registry (i.e. RBS, promoters, β-carotene, etc), we also used two genes from the SAR86 uncultured bacteria. These genes are proteorhodopsin, which was extracted from the Registry (BBa_K773002) and blh (15,15’-β-carotene dioxygenase), which was synthesized by Genescript. There is no associated risk level with the uncultured bacteria SAR86, however we are using only DNA sequences that encodes for genes, which carry distinct functions that are no harmful to humans, or the environment. We have clarified this issue with iGEM Safety Office.
We did not use any virulence factors in our organisms.
The parts we used are to be considered safe as single parts and also as combined. Environmental dispersion of those parts would not represent a biological hazard or danger.
Working Safely... with Organisms
All the bacterial strains used are from Risk Group 1. We used the following strains:
- One Shot® TOP10 Chemically Competent E. coli
- K12 - NEB 10-beta E. coli
- K12 - JM109 E. coli
- BL21 - NEB Express E. coli
