Life Science and Medical News from Around the Globe
Discovery of Pathogen Toxin May Help Fight Destructive Honeybee Disease
University of Guelph researchers in Canada hope their new discovery will help combat a disease killing honeybee populations around the world. The researchers have found a toxin released by the pathogen that causes American foulbrood disease — Paenibacillus larvae (P. larvae) — and developed a lead-based inhibitor against it. The study was published online on December 4, 2014 in the Journal of Biological Chemistry. The finding provides much-needed insight into how the infection occurs, said Dr. Rod Merrill, a professor in Guelph’s Department of Molecular and Cellular Biology and a study co-author. It also could lead to natural and more effective approaches for fighting the most widespread and destructive of bee brood diseases. “We are the first to do this,” said Dr. Merrill, who conducted the study with graduate student Daniel Krska. Also involved were post-doctoral researchers Drs. Ravi Ravulapalli and Miguel Lugo, technician Tom Keeling, and Harvard Medical School’s Dr. Rob Fieldhouse. American foulbrood is found throughout Ontario and Canada, and affects both the honeybee industry and pollinator populations. Honeybees are among the world’s most important pollinators, and their numbers are already falling globally because of disease, pesticide use, climate change, and other factors. The disease spreads readily through spores transmitted within and between colonies by adult bee carriers, Dr. Merrill said. Developing larvae are infected by eating the spores. The larvae die but not before releasing millions of additional spores into the colony. As well, the hive’s weakened state attracts “robber bees” looking for honey, which then spread the disease to other colonies.