"As a scientist, that's what you live for," said Barton, who combined a childhood passion for caving with her microbiology research. "Just like in cave exploration, it's the discovery of the unexpected that keeps you going back for more."
Barton added that the study's findings should help scientists developing antibiotics for future use to anticipate ways in which bacteria might adapt to resist the effects of new medicines.
Spellberg said the findings underscore the need for measures like the one taken Wednesday by the FDA. In 2010, the agency said that nearly 29 million pounds of antibiotic agents were fed to the nation's livestock each year. That practice accelerates bacteria's adaptation to the drugs, he said.
But Spellberg added that the federal government should take a more activist role in ensuring that the development of new antibiotic agents — a risky and expensive enterprise that has scared off many pharmaceutical companies — continues. The Generating Antibiotic Incentives Now (GAIN) Act, a bill now pending in Congress, would create economic incentives for drug companies to invest in developing new antibiotics, he said.