Biologists at UC San Diego have found that a method they developed to identify and characterize new antibiotics can be employed to screen natural products quickly for compounds capable of controlling antibiotic resistant bacteria. The researchers, who published their findings in this week's edition of the Journal of Antibiotics, say their latest discovery could permit chemists and others to understand how mixtures of potential antibiotics from microorganisms work without first purifying them. It builds on their development two years ago of a new way to rapidly identify new compounds capable of killing bacteria.

"Our initial discovery allowed us to perform the equivalent of an autopsy on bacterial cells and is changing the way industry searches for new antibiotics from collections of pure chemicals," said Kit Pogliano, a professor of biology at UC San Diego who headed the research team. "But we didn't know if it would work for identifying antibiotics found in natural product extracts, which are very complex mixtures frequently filled with multiple types of antibiotics."

"We've now shown that our method is a powerful way to identify antibiotics from natural products and understand how they work before they are ever purified," she added, "potentially shaving years off of screening efforts by identifying which organisms and growth conditions produce interesting bioactive molecules."

Most of the world's clinically useful antibiotics are derived from molecules referred to as natural products because they are naturally produced by microorganisms. This includes penicillin and streptomycin, the first two antibiotics widely used clinically beginning in the 1940's. As pathogens evolved resistance to penicillin and streptomycin, new natural product antibiotics were needed.