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'''Felisa Wolfe-Simon''' is an American microbial geobiologist and biogeochemist. In 2010, Wolfe-Simon led a team that discovered GFAJ-1 ("Give Felisa A Job"), an arsenate-resistant bacterium that they claimed was capable of substituting arsenic for a small percentage of the phosphorus in its DNA, even implying that they were extra-terrestrial in origin. GFAJ-1 was isolated from arsenic-rich Mono Lake in California. Her team used a radioactive arsenate isotope (73-As) and expensive but inconclusive X-ray absorption studies (XAS measurements) at SSRL and SLAC.<ref>http://cen.acs.org/articles/90/i29/Two-Studies-Rebut-Arsenic-Based.html</ref>

'''Felisa Wolfe-Simon''' is an American microbial geobiologist and biogeochemist. In 2010, Wolfe-Simon led a team that discovered GFAJ-1 ("Give Felisa A Job"), an arsenate-resistant bacterium that they claimed was capable of substituting arsenic for a small percentage of the phosphorus in its DNA, even implying that they were extra-terrestrial in origin. GFAJ-1 was isolated from arsenic-rich Mono Lake in California. Her team used a radioactive arsenate isotope (73-As) and expensive but inconclusive X-ray absorption studies (XAS measurements) at SSRL and SLAC.<ref>http://cen.acs.org/articles/90/i29/Two-Studies-Rebut-Arsenic-Based.html</ref>

These claims received wide publicity at the time in part because of a NASA press-release style video presentation and because of Wolfe-Simon's gender, youth and charisma. Experts soon expressed doubts in her claims but Wolfe-Simon delayed sharing samples of CFAJ-1 for a year. In 2011, University of British Columbia microbiologist Rosie Redfield, obtained a sample of GFAJ-1 from Wolfe-Simon's team and attempted to replicate the results. Redfield used more traditional laboratory techniques and failed to reporduce Wolfe-Simon results. Last posted on her Twitter account as "ironlisa" in May 2011.<ref>https://twitter.com/ironlisa</ref>

These claims received wide publicity at the time in part because of a NASA press-release style video presentation and because of Wolfe-Simon's gender, youth and charisma. Experts soon expressed doubts in her claims but Wolfe-Simon delayed sharing samples of CFAJ-1 for a year. Wolfe-Simon last posted on her Twitter account as "ironlisa" in May 2011.<ref>https://twitter.com/ironlisa</ref> Time magazine named her to their list of 100 most influential people in the world for 2011.<ref>http://content.time.com/time/specials/packages/article/0,28804,2066367_2066369_2066250,00.html</ref>

 

In 2011, University of British Columbia microbiologist Rosie Redfield, obtained a sample of GFAJ-1 from Wolfe-Simon's team and attempted to replicate the results. Redfield used more traditional laboratory techniques and failed to reporduce Wolfe-Simon results.

In 2012, two reports refuting the most significant aspects of the original results were published in the same journal in which the original findings had been previously published.<ref> Erb, T. J.; Kiefer, P.; Hattendorf, B.; Gunther, D.; Vorholt, J. A. (2012). "GFAJ-1 Is an Arsenate-Resistant, Phosphate-Dependent Organism". Science. 337 (6093): 467–470. doi:10.1126/science.1218455</ref><ref>Reaves, M. L.; Sinha, S.; Rabinowitz, J. D.; Kruglyak, L.; Redfield, R. J. (2012). "Absence of Detectable Arsenate in DNA from Arsenate-Grown GFAJ-1 Cells". Science. 337 (6093): 470–473. doi:10.1126/science.1219861.</ref>

In 2012, two reports refuting the most significant aspects of the original results were published in the same journal in which the original findings had been previously published.<ref> Erb, T. J.; Kiefer, P.; Hattendorf, B.; Gunther, D.; Vorholt, J. A. (2012). "GFAJ-1 Is an Arsenate-Resistant, Phosphate-Dependent Organism". Science. 337 (6093): 467–470. doi:10.1126/science.1218455</ref><ref>Reaves, M. L.; Sinha, S.; Rabinowitz, J. D.; Kruglyak, L.; Redfield, R. J. (2012). "Absence of Detectable Arsenate in DNA from Arsenate-Grown GFAJ-1 Cells". Science. 337 (6093): 470–473. doi:10.1126/science.1219861.</ref>