Engineered microorganisms for environmental release: current situation and future perspectives.

Engineered microorganisms for environmental release (EMERs) hold a considerable potential for bioremediation of sites polluted with urban and industrial emissions. The growing availability of EMERs with phenotypes that can help recovering polluted sites and degraded ecosystems could become a phenomenal tool to tackle some of the most pressing contamination problems at very different scales worldwide. Yet, while their delivery to diverse environmental targets could have an immense benefit, the regulatory roadmap for permitting release-in particular in the European Union-is controlled by strict policies which become actual deterrents for the development of the field. In this Perspective, we have mapped the current state of regulatory affairs and entertain ways of moving from the existing legislation on genetic engineering to an informed discussion about the future of this technology, highlighting several important aspects of the new generation of molecular tools for precision genetic engineering. Furthermore, we advocate advancing towards a fresh mindset in which EMERs are not perceived as artificial intrusions into the natural world, but as our main allies to combat much of the damage that we have inflicted to the planet.