This high enantioselectivity is especially relevant for the production of active pharmaceutical ingredients, where stereochemistry can determine biological function. Tailor-made enzymes enable enantioselective epoxide synthesisThe newly characterised GST-type enzymes catalyse the transformation of styrene into epoxides with remarkable regio- and stereoselectivity. Nature-inspired catalysis opens new paths for pharmaceutical productionThe biological reaction mimics natural detoxification pathways of epoxides in the human body. The enzymes were isolated from microbial degradation pathways of styrene, a known environmental pollutant, transforming it into useful building blocks. The high selectivity, low energy input, and environmentally friendly conditions offer significant advantages over conventional methods.