NASA researchers discovered Thursday that life can exist in some extreme circumstances.
Mono Lake in California, Oregon’s neighbor to the south, is home to the first known microorganism on Earth that thrives and reproduces using the toxic chemical arsenic. Their discovery changes what people previously thought about the existence of life. This is the first-known organism to use arsenic in its basic metabolism and genes.
NASA’s discovery has implications for the existence of extraterrestrial life.
“The definition of life has just expanded,” said Ed Weiler, NASA associate administrator for the Science Mission Directorate, in a statement. “As we pursue our efforts to seek signs of life in the solar system, we have to think more broadly, more diversely and consider life as we do not know it.”
NASA astrobiology researchers published their findings in the journal Science. University astronomy professor James Schombert used to work at NASA and heard about this recent discovery.
“The (research) team has basically discovered that life is more robust than previously thought,” Schombert wrote in an e-mail. “Basically what they found was that arsenic can serve in the place of phosphorus.”
Scientists and experts previously believed that without carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur, life could not exist.
“We know that some microbes can breathe arsenic, but what we’ve found is a microbe doing something new ­— building parts of itself out of arsenic,” Felisa Wolfe-Simon, NASA research team’s lead scientist, said in a statement. “If something here on Earth can do something so unexpected, what else can life do that we haven’t seen yet?”
NASA’s discovery will change biology textbooks and expand NASA’s search for life outside of Earth.
Mono Lake, one of the oldest lakes in North America, is a saline lake located in central California home to trillions of brine shrimp and alkali flies. Researchers chose the lake for experimentation because of its odd and unique chemical makeup, such as its high levels of arsenic, salinity and alkalinity. This unique makeup is due to Mono Lake being isolated from its fresh water sources for 50 years.
The research team grew bacteria from the lake with a diet lean in phosphorous and abundant in arsenic. The researchers then proceeded to remove the phosphorous from the experiment and replaced it with arsenic. They were shocked to find the bacteria thriving instead of dying.
“Until now, a life form using arsenic as a building block was only theoretical, but now we know such life exists in Mono Lake,” Carl Pilcher, director of the NASA Astrobiology Institute, said in a statement.
[email protected]