Team:KULeuven/Applications

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KULeuven iGEM 2011

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Applications

Our project, E.D.Frosti can stimulate ice crystallization and ice melting depending on the given stimulus. We’ve already discussed the safety of this project but what could be the major benefits for people all over the world? Let’s go over some possible applications of our E.D.Frosti.

Let’s start with the possibilities of inducing ice crystallization. Thinking big we could save the arctic by inhibiting its meltdown, but also on a smaller scale mankind could be helped. As our thermodynamic data show, the degree of supercooling will be lowered in the presence of Ice Nucleating Proteins. This means that ice crystallization will start at higher temperatures, and significant amounts of energy can be saved during the cooling process wherein ice is generated. Possible applications which will benefit from this energy saving can be in the medical sector, in which ice formation can be used in storage units for transplantation organs, or the generation of ice packs for cryotherapy. In addition, stimulating ice formation can be used to generate ice skating facilities, either outdoors, on lakes or rivers, or indoors, where vast amounts of energy, and thus money, can be saved to cool the water to the point of ice formation. In regard to this, we had a meeting with the Royal Belgian Ice Hockey Federation (RBIHF), more information can be found at the bottom of this page.
But why stop here? As we have proven that the INP system works, why not adapt it to work in a healthy bacterium (such as several Lactobacillus casei species) and use it to make ice popsicles in an energy-friendly manner?

Looking at the Anti-Freeze Proteins, our data demonstrates that they can be used to lower the ice nucleation point, i.e. lower the temperature at which ice will start to form. As such, they could be helpful to restrain ice formation on roads. As we pointed out in our safety analysis, using proteins instead of salt could be more beneficial for the environment. Additionally, farmers could use E.D.Frosti to spray on their crops to protect them against frost. This could lead to an enormous gain, both economically as ecologically, since a lot of blossoms freeze every year when there is a late freezing period.

Furthermore, by freezing or defrosting ice, the albedo, the reflecting power of the surface, changes. Ice has an albedo of 0.85; this means it will reflect sunbeams causing the surroundings to become very bright. In winter, when solar hours are limited, it is better to have more snow and ice because it makes the environment seem brighter and in this way people are less affected by SAD (seasonal affective disorder = winter depression)[1]. Therefore, our bacteria could help maintaining the stimulation of ice formation (of course on non-hazardous places like gardens and roadsides).

But we have to be honest; there could be some drawbacks of our project. “Hope for the best, prepare for the worst” and that is what we did. The worst case scenarios possible due to failure of our organism can be found in the safety text on our website. Even if we build in a cell death safety system in our bacterium, there are still risks when releasing it into the environment. One major case to be discussed is the public opinion of releasing bacteria into the environment. If they survive, even with the cell death mechanism, they could cause changes in top down- bottom up ecological interactions or even be hazardous. These risks could be minimized by purifying the proteins as these are the only necessary functional parts. However, this would greatly increase the costs thereby decreasing the economical benefits. Thus, the main question remains if the advantages are good enough to convince people to release our synthetically engineered organisms. This is one of the reasons why we organized a debate at our university where we talked about the ethics of synthetic biology.

References


1. Seasonal Affective Disorder

Royal Belgian Ice Hockey Federation meets E.D. Frosti




After our radio interview on the 30th of September, we were contacted by Johan Bollue. He is the Sports League Director of the Royal Belgian Ice Hockey Federation (RBIHF) with contacts in the International Ice Hockey Federation (IIHF).

Ice rinks are fun, but they use a lot of energy. That’s why the RBIHF and IIHF are constantly looking for energy saving alternatives. E.D. Frosti coated with INP, can induce ice formation at higher temperatures. And that’s why Johan Bollue was very interested in our project: they could save huge amounts of energy if E.D. Frosti works. We therefore did tests with the water from their ice rink and INP and arranged a meeting with Johan.

Results from the meeting

Friction coefficient of substances
The International Ice Hockey Federation (IIHF)) has an environmental committee that looks for energy saving alternatives for ice rinks. The development of synthetic ice seems interesting, since such rinks lack a complex infrastructure for ice formation and don’t need constant cooling. But…

An important aspect of ice and ice skating, is the friction coefficient of the ice. This friction coefficient determines the hardness of the ice and this is very important: when sliding over hard ice (low friction coefficient), the ice skater can go very fast and little snow powder is being formed. On soft ice (high friction coefficient), a lot of snow is produced and the ice skater’s speed will dramatically decrease. And there’s the problem with synthetic ice: this has a much higher friction coefficient, so when gliding over synthetic ice, small flakes are being formed which will decrease the skating speed. Also, small particles and dust will also worsen the friction coefficient. This means that the ice rink needs to be vacuumed, polished and waxed regularly.

So synthetic ice is a cheaper alternative for ice, but at the moment, the quality is bad. At the other hand, addition of E.D. Frosti to water will affect the nucleation temperature instead of the hardness. The friction coefficient and thus the hardness of the water will be more or less the same as in water without E.D. Frosti. This is a big benefit compared to synthetic ice.

Ice rink Leuven
Ice rinks are equipped with a tubular cooling system, on which different layers of water are sprayed and cooled down. But when you spray cold water on a cooling system, it will immediately freeze, resulting in cracked ice. Therefore, most ice rinks spray heated water on their cooling system, so that it gradually freezes and results in ice formation without cracks. The heating of the water of course needs a lot of energy. The ice rink in Leuven however, is equipped with a special REALice – system from Watreco, that uses a special kind of water in which oxygen has been removed (the hardness of the ice increases as well). A benefit from their system is that they can spray unheated water on their cooling system without crack formation. This already is beneficial in comparison with most other ice rinks. So where could E.D. Frosti improve their system even more?

Their cooling system is cooled down to approximately -18°C. The results from our DSC tests show that combination of their deoxyfied water and our E.D. Frosti coated with INP, induces ice formation at app. -5°C (normal water only freezes around -22°C and their water around -17°C). This difference in 13°C, could save a lot of energy. But is this really feasible?

Feasibility?
With the current (lack of) laws for synthetic biology and GMOs in Europe, it is not recommended to add a bacterium to water in ice rinks, even not when our system would be transferred to bacteria such as the bifidobacteria or Lactobacillus casei species. Instead of using a bacterium for the ice rinks, the use of purified INP could solve the GMO issue. When inaZ is incorporated in Pichia pastoris (a very efficient protein-secreting yeast), INP can be purified from the medium and added to the water of the ice rink.

Practically?
We also discussed whether our theoretical concept could be turned into practice. Johan explained us that when ice rinks are used extensively, they need to be mopped regularly, up to one time per hour. In this mopping process, the upper layer of the ice is scratched off and water is added. INP can be added along with the water and once it cools down to -5°C, it will freeze. The ice layer that has been scraped off, can be reused since INP stays active after thawing of the ice.

Conclusion

E.D. Frosti has a lot of potential in saving loads of energy with ice rinks. Since there are problems with using a bacterium in a public place, the use of purified INP could be applied in the future. When we compare synthetic ice with water that contains E.D. Frosti, we see that the quality of the ice (expressed in the hardness and the friction coefficient) is worse in synthetic ice. This is due to the fact the addition of E.D. Frosti only affects the ice nucleation temperature.

Aftermath

This meeting was very informative, both for Johan and our team. We could convince him of the potential strength of E.D. Frosti and we got a lot of insight in process of ice formation in ice rinks. Johan proposed to show us the cooling system of the ice rink in Leuven after Boston. We are also going to try to experimentally check properties of water with E.D. Frosti such as hardness and the friction coefficient.