NASA was WRONG on arsenic-gobbling aliens, claim boffins
Weird Earth bacteria need their six a day
Scientists in Switzerland have blown apart the theory that some bacteria can live off arsenic, disproving a controversial 2010 study by NASA.
Felisa Wolfe-Simon, one of the space agency's astrobiologists, faced scepticism when she declared two years ago that she had discovered the snappily named GFAJ-1* microbe thriving in the arsenic-rich, phosphorus-depleted Mono Lake in eastern California.
It was a surprise find because phosphorus is one of the six essential ingredients for life as we know it, yet NASA's bug was apparently able to metabolise poisonous arsenic to grow.
Rather than back notions of unearthly lifeforms living off a toxic chemical element, two separate studies published in the past week have skewered the arsenic-loving bacteria conclusions. Findings from the University of Zurich suggest that GFAJ-1 is dependent on phosphorus and rather resistant to arsenic.
A second study from the University of British Columbia in Vancouver, Canada, also reached the same conclusion. Its team leader, Dr Rosemary Redfield, said the original results may have been affected by phosphate contaminant in the arsenic.
Dr Wolfe-Simon of NASA's Astrobiology Institute said the latest findings do not nix her work.
"There is nothing in the data of these new papers that contradicts our published data," she said in an email to the Associated Press. Her team "continues to build upon its finding of the extreme resistance to arsenic poisoning".
GFAJ-1 Is an Arsenate-Resistant, Phosphate-Dependent Organism was published in Science on 8 July. ®
* GFAJ apparently stands for Give Felisa a Job, according to the Wall Street Journal.