The team of researchers led by Sean F. Brady, a chemist and associate professor, and his colleagues at Rockefeller University in NY looked at the bacterial DNA from 2,000 soil samples that were taken from different parts of United States.
The discovery came from a citizen science project - Drugs from dirt - started by Sean Brady of the Rockefeller University, US. The project asked people to send in soil so that the DNA from microbes could be extracted and sequenced.
Brady's team was looking for genes that code for calcium-dependent antibiotics, a small family of cyclic peptides that require calcium for their activity. Because all the genes needed to make a molecule in bacteria cluster together, identifying the marker gene enabled them to find all the other genes in the gene cluster. (Also, "mal" means bad in Latin, and "cide" means to kill.) It is a distant relative of daptomycin, a powerful antibiotic that uses calcium to disrupt bacterial cell walls.
Antibiotics found in these samples killed a variety of multi drug-resistant, disease causing bacteria.
Brady added that, "We're taking DNA directly out of soil samples". 'This might be a way of reducing resistance'.
This particular type of calcium-dependent gene is popular among microbiologists because it is believed it could be a great indicator for a much longer sequence controlling the production of antibiotics.
Scrutinizing soil samples, USA researchers have discovered a new class of antibiotics capable of killing drug-resistant, disease-causing bacteria. One (malacidin A) successfully sterilised a wound infected by MRSA in a rat model.
'Likewise, the malacidins showed no significant toxicity against mammalian cells at the highest concentrations tested.
'We think the different mode of action is really exciting. After they had sorted through the material, the scientists found, said Brady, that "most of what's there is completely unknown, and that's the future". 'Maybe we are not in such dire straits with antibiotics.
Of course, we won't see this antibiotic on the shelves tomorrow.
The antibiotics' unique approach to killing pathogens targets bacteria's cell walls, which did not cause drug resistance in the laboratory, a United States study found.
Around 700,000 people a year are known to die from drug-resistant superbugs, which have evolved since the last family of antibiotics was developed in the 1980s.
This is not the first time that scientists have discovered antibiotics from the soil, but it has proven hard for researchers to identify a a bacterial species that could become a drug, as the scientists did here.