Each year, an average of 120 gigatonnes of carbon dioxide (CO2) world-wide is released through soil and vegetation respiration. Plants are capable of taking in nearly 123 gigatonnes through photosynthesis in the same period. But as humans release another ten gigatonnes of carbon dioxide into this cycle, mainly by burning fossil fuels such as crude oil and natural gas, there are seven gigatonnes of excess CO2. "And these seven gigatonnes are our big problem," says Thomas Dandekar, who holds the Chair of Bioinformatics at the University of Würzburg in Germany. They fuel global warming and cause global temperatures to rise at an alarming rate.
While searching for a solution to fix this problem, Dandekar and his colleagues believe to have discovered a promising way forward. They are studying plants which are capable of absorbing residual carbon dioxide more effectively thanks to a modified metabolism. The scientists published their findings in the December 2019 issue of the journal Trends in Biotechnology.
Bioinformatics researchers usually work with mathematical computer models. Over the past months, Thomas Dandekar and his team have been studying whether the metabolic networks of plants can be modulated so as to enable the plants to fix more carbon dioxide. To achieve this, the scientists combined two different methods to modulate the metabolism of the plant cell. By performing complex calculations, they found out that the combination they chose enables plants to absorb five times more carbon dioxide than in the normal state.
Now their theoretical calculations need to be tested in practice. Muhammad Naseem, a colleague of Dandekar, is in charge of conducting these experiments. Naseem also works at Zayed University in Abu Dhabi. He plans to start the practical test there in the course of this year. "We will experiment with tobacco plants and thale cress, also known as Arabidopsis thaliana, which are both easy to modify," the scientist explains.
"If we continue on our current path, climate change will have disastrous consequences," Dandekar warns. He believes that the next decade must be used to find new ways of removing the carbon dioxide that has already been released into the atmosphere, reducing CO2 emissions and developing strategies to adapt to the consequences of climate change. If successful in practice, the Würzburg research would kill two birds with one stone, for not only do the modulated plants absorb more carbon dioxide, they also deliver higher yields.
Adapting to a changing climate is currently even more important for countries outside of Europe than for Germany, as Naseem explains. The consequences are already clearly noticeable especially in the United Arab Emirates. Based on model forecasts, climate researchers warn that temperatures in the major cities in the Persian Gulf could rise to 50 or even 60 degrees Celsius.
The scientist emphasises the urgency of curbing CO2 emissions. He considers the idea of combining two modulation methods a blessing because it would enable two problems of humanity to be addressed – provided that the computer analyses are congruous with the behaviour of the plants in the field. "The two problems of climate change and feeding the world population are closely connected," says Naseem.
Climate change causes scorched fields, withering plants and complete crop failure due to drought in some regions. Plants with modulated metabolic pathways could not only fix more CO2, they would also produce more biomass thanks to the genetic modification.
Synthetic rewiring of plant CO2-sequestration galvanizes plant biomass production. Muhammad Naseem, Özge Osmanoglu and Thomas Dandekar. Trends in Biotechnology. DOI: 10.1016/j.tibtech.2019.12.019