'Arsenic Life' Claim Refuted by 2 New Studies

This scanning electron micrograph shows a strain of the arsenic-eating bacterium called GFAJ-1. (Image credit: Science/AAAS.)

Leader of the 2010 study, Felisa Wolfe-Simon had acknowledged very low levels of phosphate within their study samples; however, they concluded the contamination would've been insufficient to allow GFAJ-1 to grow.

Now the two separate studies find that Wolfe-Simon's medium did contain enough phosphate contamination to support GFAJ-1's growth. It's just that GFAJ-1, a well-adapted extremophile living in a high-arsenic environment, is thrifty, and is likely capable of scavenging phosphate under harsh conditions, helping to explain why it can grow even when arsenic is present in its cells.

The finding soon spurred a lively debate, with outside researchers criticizing the paper's methods. "The basics, growing the bacteria and purifying the DNA, had a lot of contamination problems," said microbiologist Rosie Redfield of the University of British Columbia, in February. Redfield is the author of one of the newly published Science papers.

This story was provided by LiveScience, sister site to SPACE.com. Follow LiveScience on Twitter @livescience. We're also on Facebook & Google+.

For the science geek in everyone, Live Science breaks down the stories behind the most interesting news and photos on the Internet, while also digging up fascinating discoveries that hit on a broad range of fields, from dinosaurs and archaeology to wacky physics and astronomy to health and human behavior. If you want to learn something interesting every day, Live Science is the place for you.