This laboratory image shows Staphylococcus aureus bacteria streaked in the shape of a sex steroid, like testosterone. The left shape is of wild-type S. aureus, with the lighter halo around the shape indicating hemolysis, or the breakdown of red blood cells, releasing their hemoglobin into the surrounding fluid. The right shape is a quorum-sensing mutant strain of S. aureus, which cannot damage blood cells. Photo courtesy UT Southwestern Testosterone, long implicated in sex-ba

This image shows colonies of methicillin-resistant Staphylococcus aureus bacteria. Photo credit: Janice Haney Carr, Jeff Hageman, M.H.S, U.S. Centers for Disease Control and Prevention Researchers at the University of California San Diego School of Medicine have discovered a previously unrecognized mechanism by which Staphylococcus aureus delays wound healing. In a study, published in The   Journal of Clinical Investigation , the researchers found that quorum sensing—a proces