Chlamydia-like bacteria discovered in Great Barrier Reef

Newswise — Fresh research, issued in Sciences Advances, has disclosed a Chlamydia-like microorganism in corals of the Great Barrier Reef that may aid researchers in comprehending the coral microbiome and its potential effect on coral reef well-being. Led by the University of Melbourne in partnership with the Australian Institute of Marine Science (Townsville) and the University of Vienna, the study identified two bacterial assemblages within coral tissues, including a close relative of the chlamydia-causing bacteria (Chlamydiales) and Endozoicomonas. The research, backed by an ARC Laureate Fellowship, introduces another level of intricacy to the comprehension of coral reef well-being. The principal investigator from the Faculty of Science at the University of Melbourne, Dr Justin Maire, mentioned that Chlamydiales, a bacterial order encompassing pathogens responsible for chlamydia infections in mammals, has never been previously documented in corals. "We collaborated with Chlamydiales experts Dr Astrid Collingro and Professor Matthias Horn from the University of Vienna, and determined that these bacteria derive nutrients and energy from their hosts in order to survive," Dr Maire explained. "The newfound Chlamydiales share many resemblances with mammalian pathogens, but it remains uncertain whether they are detrimental or advantageous to corals. There is a possibility that this bacterium obtains nutrients and energy from other bacteria associated with corals, and for those of us studying coral biology, the prospect of bacterial interactions within coral tissues is quite exhilarating." The senior author of the study, University of Melbourne Professor Madeleine van Oppen, noted that the other bacterium discovered, Endozoicomonas, is known to be widespread in corals and is generally considered beneficial due to its ability to generate B vitamins and antimicrobial compounds. "One of the focal points in my laboratory is the development of bacterial probiotics for corals, which can enhance their resistance to thermal stress and increase survival rates caused by climate warming," Professor van Oppen stated. "We still possess limited knowledge about the functions of bacteria associated with corals, and this new study will help us ascertain whether probiotics are a viable solution and if bacteria such as Endozoicomonas are the most suitable candidates for the task."