Connor Sweeney

Biotechnologists are increasingly planning not only to engineer microbes in the lab — but to then release them into the field. These microbes can fix nitrogen for plants or clean up pollutants. Good or bad, this review is the most substantive piece ever written on the issue. *** It was published in June and (full disclosure) I know the authors. The review covers lots of different applications for genetically modified microbes, including self-healing cement, oil cleanups, and biosensors for landmine detection. There have been at least 57 actual studies testing engineered microbes released into soils. Half of those field-tested microbes were designed to fix nitrogen, while 19% were tested as pesticides, and just 3% as "living biosensors." Despite a large number of field trials, only a handful of genetically-engineered microbes have been approved for commercial use. Agrobacterium radiobacter K1026, for example, is designed to stop Crown Gall disease in trees. It was the world's first commercially approved, engineered microbe for environmental release (in 1988). Also, a strain of Pseudomonas putida carrying a recombinant phenol-degrading pathway, designed to clean up phenol pollution, has also been approved for commercial use. Importantly, this review covers various regulations and how to get around them, mainly by using non-pathogenic species and avoiding certain genetic modifications to streamline approvals. If you want to understand where biotechnology is going, you should read this paper.