Three weeks ago, Felisa Wolfe-Simon, 33, a former performance oboist with a doctorate in oceanography and a NASA fellowship in astrobiology, published a paper online in Science about bacteria that can use arsenic instead of phosphorus in DNA and other biomolecules. Four days before the publication, NASA sent out a media advisory that it would hold a press briefing "to discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life." That led to wild speculations on the Web about extraterrestrial life, and when the paper was published, many headlines made the most of the "alien" nature of the discovery by Wolfe-Simon and her colleagues at the U.S. Geological Survey in Menlo Park, California.

Then came a torrent of criticism by scientists. A highly critical blog post by Rosie Redfield, a microbiologist at the University of British Columbia, Vancouver, quickly drew hundreds of comments, many also finding fault with the study. Wolfe-Simon and her co-author Ronald Oremland then came under attack by journalists when they declined to respond to media calls for a response to these comments. On 16 December, the authors posted responses to some of the issues, and Science will publish technical comments and responses in early 2011. In the meantime, Wolfe-Simon agreed to share some of her thoughts in an interview with Science's news department, which covered the original finding in early December. The following has been edited for brevity.

To read the interview, click here.