The joint project ECOX, led by the Department of Environmental Biotechnology and Bioprocess Engineering of the Fraunhofer IGB, is concerned with the establishment of an enzymatic-chemocatalytic process for the material use of methane from biogas. The aim is to combine chemical and enzymatic process steps in such a way that methane can be converted as efficiently as possible into methanol and formic acid. Such a process is intended to create the basis for the use of biogas as a carbon source, in contrast to the conventional combustion of biogas for energy generation. In this project, the partners at the Fraunhofer IGB, the University of Halle-Wittenberg and the Leibniz Institute for Catalysis in Rostock are working together on an interdisciplinary basis.
The Industrial Biotechnology Group of the Fraunhofer IGB together with the University of Halle-Wittenberg is working on the production and optimization of the three enzymes methane monooxygenase (MMO), methanol dehydrogenase (MDH) and formaldehyde dismutase (FDM). In order to ensure an efficient process, these biocatalysts must above all have a high activity and stability, as well as being easy and inexpensive to produce. For MDH and FDM, which are mainly developed at Fraunhofer IGB, bacterial expression systems such as Escherichia coli or Bacillus subtilis, but also eukaryotic systems such as the yeasts Komagataella pastoris or Kluyveromyces lactis are considered. The characterization and optimization of the enzymes includes on the one hand catalytic parameters such as pH and temperature optimum, which have to be coordinated and, if necessary, adjusted between the enzymes. On the other hand, the enzymes should be specifically modified in order to enable their application on different carrier materials. In this way, stable catalysts can be developed which enable an efficient process through multiple use.