A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus

1. Felisa Wolfe-Simon¹,²,*,
2. Jodi Switzer Blum²,
3. Thomas R. Kulp²,
4. Gwyneth W. Gordon³,
5. Shelley E. Hoeft²,
6. Jennifer Pett-Ridge⁴,
7. John F. Stolz⁵,
8. Samuel M. Webb⁶,
9. Peter K. Weber⁴,
10. Paul C. W. Davies¹,⁷,
11. Ariel D. Anbar¹,³,⁸ and
12. Ronald S. Oremland²

+ Author Affiliations

1. ¹NASA Astrobiology Institute, USA.
2. ²U.S. Geological Survey, Menlo Park, CA, USA.
3. ³School of Earth and Space Exploration, Arizona State University, Tempe, AZ, USA.
4. ⁴Lawrence Livermore National Laboratory, Livermore, CA, USA.
5. ⁵Department of Biological Sciences, Duquesne University, Pittsburgh, PA, USA.
6. ⁶Stanford Synchrotron Radiation Lightsource, Menlo Park, CA, USA.
7. ⁷BEYOND: Center for Fundamental Concepts in Science, Arizona State University, Tempe, AZ, USA.
8. ⁸Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ, USA.

1. *To whom correspondence should be addressed. E-mail: felisawolfesimon@gmail.com

Abstract

Life is mostly composed of the elements carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus. Although these six elements make up nucleic acids, proteins, and lipids and thus the bulk of living matter, it is theoretically possible that some other elements in the periodic table could serve the same functions. Here, we describe a bacterium, strain GFAJ-1 of the Halomonadaceae, isolated from Mono Lake, California, which substitutes arsenic for phosphorus to sustain its growth. Our data show evidence for arsenate in macromolecules that normally contain phosphate, most notably nucleic acids and proteins. Exchange of one of the major bioelements may have profound evolutionary and geochemical significance.