Ars Technica: How to reduce the amount of carbon dioxide pumped into the atmosphere has been one of the main scientific challenges facing humanity over the last 20 years. One potential solution is to recycle the CO₂ into something more useful via a catalytic reaction. Using an enzyme that converts nitrogen gas (N₂) to ammonia (NH₃), Lance Seefeldt at Utah State University and his colleagues have developed the first biochemical process that mimics inorganic catalytic reactions. That catalytic process is similar to the conversion of CO₂ into methane (CH₄), so Seefeldt’s team engineered the enzyme to process CO₂ instead of N₂. Before slowing down, the engineered enzyme successfully converted CO₂ for 20 minutes, a rate comparable to inorganic catalysis. Seefeldt’s team also discovered that the enzyme combined CO₂ with acetylene (C₂H₂) to create propylene (C₃H₆), an ingredient in many plastics. This is the first known catalytic reaction, biological or inorganic, known to create propylene. The success of the enzymatic conversion provides a new method for recycling CO₂ and opens new avenues of research in catalysis and bioengineering.