BEIJING, May 18 (Xinhuanet) -- A molecule taken from bacteria found in soil in South Africa has proved potent against diseases resistant to common antibiotics, according to Nature Thursday.

    Researchers have tested 250,000 compounds extracted from microorganisms for antibiotic properties. Platensimycin, isolated from a strain of Streptomyces platensis found in a soil sample from South Africa, showed both strength and discretion in biochemical assays, targeting and defeating pathogens while seeming to show little danger of unwanted interactions. It has already proven effective in curing mice infected with antibiotic-resistant bacteria.

    Most classes of antibiotics were discovered in the 1940s and 50s and work by interfering with the formation of a bacterium's walls, proteins or DNA, so that it cannot reproduce and spread. But, as bacteria reproduce, their DNA mutates, which can make them immune to the interference of drugs. As the use of antibiotics has risen in the past few decades, strains of Staphylococcus aureus and various Enterococcus bacteria have shown resistance to the most powerful antibiotics in the modern medical arsenal.

    "The path ahead remains a long one that includes further preclinical study, and, if these studies are successful, extensive clinical trials for safety and efficacy in humans," writes Eric Brown of McMasters University in Ontario. If it passes all of those tests, platensimycin could be the third new antibiotic--and the strongest--to reach patients in the last 40 years. Enditem