Reconstructing microbial genomes from the environment
Microbe communities are everywhere, from the environment to our own bodies. Human and environmental microbiomes are diverse and play a range of key roles in human health and the functioning of healthy ecosystems. Thanks to the recent advent of metagenomics, an efficient and cost-effective DNA sequencing technology, our knowledge of these communities has grown significantly in recent years. In fact, the pace of microbiome research has accelerated (learn more in this recent episode of the CORDIScovery podcast, ‘The wonderful world of the gut microbiome’). Metagenome-assembled genomes (MAGs) reconstructed through these techniques are hugely valuable to furthering our understanding of diverse ecological niches of microbes, which could have a wide range of applications in biotechnology, medicine and even climate science. Yet the quality of reconstructed MAGs rests on a technique known as binning, where groups of nucleotide sequences from an organism are placed into bins depending on how often they appear across different samples. If there aren’t many samples of a particular organism, the grouping becomes more difficult and reconstruction is poor. In the EU-funded Metagenome binning project, undertaken with the support of the Marie Skłodowska-Curie Actions(opens in new window) programme, researchers aimed to address these challenges by developing a new algorithm to improve binning in situations where samples are scarce. The work will help scientists gain a better understanding of human and environmental microbiomes. “Improved binning leads to better reconstruction of high-quality microbial genomes from environmental samples, for example from the human gut,” says Yazhini Arangasamy(opens in new window), Marie-Curie postdoctoral fellow at the Max-Planck Institute for Multidisciplinary Sciences(opens in new window).
Cleaner fuel feedstocks
Today, most SAF is produced through the hydrotreated esters and fatty acids (HEFA) method – a refining process that converts vegetable oils, used cooking oils, animal fats or other lipid-rich wastes into a fuel that is chemically almost identical to conventional jet kerosene. The drawback is that supply of waste oils is limited, costly and often imported with over half coming from China and Malaysia. The EU-funded GAFT project, supported by the European Innovation Council, has developed a completely different method for producing aviation fuel feedstock using CO2, water, and renewable electricity. Marien de Jonge is the Chief Scientific Officer and one of the co-founders of GAFT, the Dutch company of the same name that leads this research. He explains that the goal of the project was to “develop new ways to produce biofuels and e-fuels that can be used to make SAF, mainly by creating locally produced long-chain lipid feedstocks suitable for the HEFA process.” Instead of depending on used cooking oil, however, GAFT’s clean microbial lipid feedstock will be produced through a unique process combining electrochemistry and fermentation.
A new biological and electrochemical route to SAF
CO2, water and electricity are used in a patented process to produce potassium formate, which is then converted into formic acid. At the same time, a non-GMO microorganism capable of fermenting various feedstocks is used to produce lipids, including triglycerides, which are key precursors for aviation fuel. “Together, these technologies help create a pathway in which renewable electricity and captured CO2 are transformed into the essential building blocks for sustainable aviation fuel,” said de Jonge.
Toward scalable, local fuel production
One of the main advantages of the GAFT approach is the ability to replace imported waste oils with local, renewable feedstocks. De Jonge emphasises that this opens the door to “a more scalable and domestic SAF supply chain,” helping the industry move beyond its dependence on limited HEFA inputs. The process also produces a valuable by-product. The remaining biomass is a protein-rich material that can be used as an ingredient in aquafeed, providing a valuable and sustainable alternative to traditional fishmeal or soy-based feeds.
Looking ahead
Scaling up remains the biggest challenge, as well as securing investment. Negotiations are, however, progressing and the long-term ambition is clear. “GAFT aims to establish a fully scalable, circular, and sustainable supply chain for SAF that relies on locally produced microbial lipids and renewable electricity rather than limited, imported feedstocks like used cooking oil,” stated de Jonge. If successful, the technology could expand SAF production, cut emissions and reduce aviation’s reliance on fossil fuels. And although the road ahead includes engineering, investment and regulatory challenges, the GAFT team believes their model points towards a more resilient future for aviation fuel production.
