Soil may be a source of antibiotic resistance

Aug 31, 2012
Originally published on August 30, 2012 5:02 pm

Soil bacteria may be helping to make disease-causing bacteria resistant to antibiotics.

That’s according to a new study out of Washington University.

Lead researcher, microbiologist Gautam Dantas, says he and his colleagues found seven genes in farmland soil bacteria that are identical to genes in human pathogens – and that provide resistance to a wide range of antibiotics.

Dantas says the genes for antibiotic resistance were clustered together with other genes known to move DNA between bacteria.

“Now you have these multi-drug resistance clusters, these genes clusters, which in principle, in a single transfer event, could transfer multi-drug resistance from one bacteria to the other,” Dantas said.

Dantas says soil bacteria could be passing genes to human pathogens, or vice versa.

“Even though these bacteria might live most of the time in different spaces, associated with humans, or associated with the soil, or associated with aquatic environments, they have the ability to exchange these genes,” Dantas said. “And they’re exchanging genes that are clearly going to compromise our ability to treat infectious disease.”

Dantas says antibiotics are being overused both in human medicine and in agriculture, and combatting antibiotic resistance is going to take a joint effort in agriculture and medicine.

“We need to be better about how we regulate antibiotic use in animals, and at the same time, better about how we regulate the prescription of antibiotics in the clinic,” Dantas said.

His research is published in the journal Science.

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