This means that the bacteria were able to build all of their biomass from air. This feat, which involved nearly a decade of rational design, genetic engineering and a sped-up version of evolution in the lab, point to an exciting new means of developing carbon-neutral fuels.

The research, which was conducted in the laboratory of Professor Ron Milo of the Weizmann Institute of Science, was reported this week in Cell.

The study began by identifying crucial genes for the process of carbon fixation—the way plants take carbon from CO2 for the purpose of turning it into such biological molecules as protein and DNA. After adding and rewiring the needed genes, the researchers found that many of the "parts" for the machinery that were already present in the bacterial genome could be used as is.