CO2 to Terpenes: Autotrophic and Electroautotrophic α‐Humulene Production with Cupriavidus necator

We show that CO₂ can be converted by an engineered “Knallgas” bacterium (Cupriavidus necator) into the terpene α‐humulene. Heterologous expression of the mevalonate pathway and α‐humulene synthase resulted in the production of approximately 10 mg α‐humulene per gram cell dry mass (CDW) under heterotrophic conditions. This first example of chemolithoautotrophic production of a terpene from carbon dioxide, hydrogen, and oxygen is a promising starting point for the production of different high‐value terpene compounds from abundant and simple raw materials. Furthermore, the production system was used to produce 17 mg α‐humulene per gram CDW from CO₂ and electrical energy in microbial electrosynthesis (MES) mode. Given that the system can convert CO₂ by using electrical energy from solar energy, it opens a new route to artificial photosynthetic systems.