Scientists have tweaked a powerful antibiotic, called vancomycin, so it is once more powerful against life-threatening bacterial infections. Researchers say the more powerful compound could eliminate the threat of antibiotic resistance for many years to come. Antibiotic resistance, in which microbes no longer respond to drugs, is quickly becoming a global health emergency. Of particular concern are so-called “superbugs,” a handful of pathogens that patients acquire in hospitals and other health care settings. Patients recovering from surgery are particularly vulnerable to the resistant, hospital-borne infections, which put them at high risk of death. Researchers at The Scripps Research Institute in La Jolla, California, modified vancomycin, invented 60 years ago and considered a last resort treatment against many of these infections. They made a key change to its molecular structure, interfering with how the bacterium, enterococcus, makes protective cells walls. In a new study published in the journal Proceedings of …