Bacteria are much more supportive than previously thought, and that is why they have become so resistant to antibiotics . This is the conclusion reached by a team of researchers from the United States in a study published today in the journal Nature . According to their experiments, when a bacterium manages to develop resistance to antibiotics, it is not satisfied with surviving and transmitting that capacity to its offspring, as was believed until now, but sacrifices itself to improve the chances of survival of the weakest of the group .
Specifically, James J. Collins, from the Howard Hughes Medical Institute (USA), and his colleagues observed the behavior of the bacterium Escherichia Coli in the presence of the antibiotic norfloxacin. And they found that the populations best able to withstand high doses of antibiotics were those in which a few resistant bacteria were dedicated to producing a steroid called indole , which offers defenseless bacteria protection against the antibiotic . This comes at a high cost for the altruistic bacterium, which "does not grow as much as it can because it is making indole for all its companions in the colony," explains Collins.
The finding raises a question for biologists: "If evolution favors the strongest, why should an individual sacrifice their own well-being for the rest of the group?" Asks Collins.
