Clean tech rises again, retooling nature for industrial use

Berkeley, California

A DECADE ago, a group of biologists, venture capitalists and computer whizzes gathered under the name "clean tech". They hoped to overturn polluting industries with microorganisms cheerily excreting industrial chemicals through the miracle of reprogramming nature's genetic code.

The idea lost billions of dollars. Genes may indeed be programmable code, akin to computer software, but it turned out nature was more complex than first believed.