Products from the bioeconomy play an important role in a sustainable future, but are dependent on cheap and available biomass as a carbon source. The availability of sustainable biomass, though, is limited by the arable area of our planet. Even by deforestation and setting up new agricultural area, we cannot provide enough arable land for both biomass for the bioindustry and food crops to solve the problem of world hunger. So if we hardly manage to feed the population, how can we guarantee the supply of biomass for other biotechnological products?
The best option would be to use CO2 from the air to form products. Recent technological advancements made it possible to convert CO2 into methanol with a great efficieny. This is where our project comes in. To take a step forward in solving this complex problem, we wanted to develop our E. coli that converts methanol to glycogen.
Glycogen is a sugar polymer that is safe to handle and can be easily converted into glucose. Therefore, it can then be used as a carbon source for almost all existing bioprocessess since those rely on sugar. Our project has the potential to make the bioindustry independent from plants and instead use CO2 from the air. Thereby not only methanol is opened up as a new carbon source but also the CO2 level in the atmosphere is reduced. We connect the bioeconomy with advanced technologies of CO2 fixation.
We decided to use the newly developed, ATP-neutral Methanol Condensation Cycle[1] to enable E. coli to take up methanol. Glycogen accumulation was achieved by combining knocking out one degradation enzyme and overexpressing the synthesis genes.
One potential solution to this global problem is the farming of algae, where simple carbon compounds using CO2 and sunlight are produced. However, the technical process of fixing CO2 that precedes our process, for example through the company sunfire, is far more efficient also compared to plants. The efficency of energy that is converted into chemical energy is about 80 times higher than the conversion of CO2 to biomass through plants and even 18 times higher than the maximal efficieny natural photosynthesis can theoretically have.[2]
Furthermore the problem is approached by mounting large areas of energy crops. Plants that are easy to maintain are used to convert CO2 to biomass. However, for this cause huge areas of the rain forest are cut down and the environment of many species is destroyed.
The main advantage of our product is that it addresses the problem in various ways. Not only can the potential of methanol as a carbon source be exploited but also the surplus CO2 in the atmosphere is utilized. It has to be considered as well that by fixing the CO2 technically, non-arable areas like deserts can be used. In addition compared to the other two approaches, our project is based on a CO2 fixing method that is far more efficient than plants. And lastly the production of glycogen from methanol with our bacteria is independent from the restricted arable land available.
The most important impact of our project is that arable land is no longer occupied to produce sugar for biotechnological processes and can instead be used to plant food crops and therefore feed the growing population. Additionally deforestation is decreased, CO2 levels are lowered and thereby our environment is protected.
References
- ↑ Bogorad IW, Chen CT, Theisen MK, Wu TY, Schlenz AR, Lam AT, Liao JC. Building carbon-carbon bonds using a biocatalytic methanol condensation cycle. Proc Natl Acad Sci U S A. 2014 Nov 11;111(45):15928-33. doi: 10.1073/pnas.1413470111. Epub 2014 Oct 29. PubMed PMID: 25355907; PubMed Central PMCID: PMC4234558.
- ↑ Die natürliche Photosynthese: Ihre Effizienz und die Konsequenzen - Hartmut Michel