Stop the presses and rewrite those science books because life as we know it has changed.
In what has been hailed as an "amazing" discovery by scientists, the toxic chemical element arsenic has effectively substituted large quantities of the element phosphorus in living bacteria microbes, according to NASA-funded research. The bacteria didn't die—instead it began to build itself out of arsenic. The discovery debunks the long held belief that carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur were the only building blocks to all known forms of life on Earth. Now, arsenic has become the seventh.
"What does that suggest? It cracks open the door to the potential we can experimentally test and show evidence of different forms of life," said Felisa Wolfe-Simon, a NASA Astrobiologist, at the Dec. 2 announcement in Washington D.C.
"Everything we know is on this tree of life," she said. "This has changed how we do this and it will help inform us of life in our planet and will inform us, hopefully, about life in other planets."
Wolfe-Simon, a research fellow in residence at the U.S. Geological Survey in Menlo Park, Calif. and the research team's lead scientist, conducted tests in the harsh environment of Mono Lake, Calif., chosen because of its unusual chemistry, especially its high salinity, high alkalinity and high levels of arsenic.
"If something here on Earth can do something so unexpected, what else can life do that we haven't seen yet?" she said.
The excitement in the scientific community stems from the new areas of research that the discovery creates. These include the study of Earth's evolution, organic chemistry, disease mitigation and opens up new frontiers in microbiology and other areas of research.
"The new areas of scientific research and the ramifications for funding are pretty significant," said Mary Voytek, director of the Astrobiology Program at NASA in D.C. Astrobiology studies life in the interplanetary context explained Wolfe-Simon.
"It's like in Star Trek, the [episode] "Devil in the Dark," with the Horta [people]," said Voytek. "The Horta were silicon-based. Imagine substituting carbon with silica. Here, it appears to be using another component. It's a huge deal."
This finding of an alternative biochemistry makeup will alter biology textbooks and expand the scope of the search for life beyond Earth, according to NASA. The research is published in this week's edition of "Science Express."
"The elements that build life have changed," said James Elser, professor at Arizona State University at Tempe. "The textbooks will have to be rewritten as of today."
Editor's Note: NASA Ames held a special viewing of the announcement. Click "play" on the video on the right for images and interview from the event.