The bacteria showed resistance to all major classes of antibiotics, regardless of whether the compounds were naturally produced, semi-synthetic, or completely synthetic.
Researchers also found that the way bacteria was resistant to vancomycin, one of the most commonly prescribed antibiotics for drug resistant staphylococcal infections, was identical to resistance found in clinics.
Furthermore, the researchers' uncovered bacteria that produced enzymes capable of breaking down or modifying or rendering inactive two recently U.S. FDA-approved antibiotics, a situation which has yet to emerge clinically for these drugs.
"The link between clinical and soil-associated resistance to vancomycin illustrates the value of studying resistance in the soil to rationally anticipate future clinical resistance," said Wright. "It suggests that the soil serves as an under-recognized source of resistance, resistance that has the potential to reach clinics.
"This work could prove to be extremely valuable to the drug development process, complementing traditional laboratory studies of clinical situations. By screening newly developed drugs for resistance in soil bacteria, not only can pharmaceutical companies can gain a better understanding of what may emerge in the future as clinical problems, but sufficient warning can be given to hospital microbiology laboratories, physicians and the drug discovery sector to allow for the development of diagnostic techniques and alternative therapies.
"Furthermore, studying enzymes that inactivate antibiotics can serve as a foundation for the development of new combination therapies for resistant bacterial strains. Studying antibiotic resistance from an evolutionary perspective is one way that researchers are attempting to stay one step ahead of resistant bacteria."