CAREER: Symbiotic Role of Bacterial Bioluminescence

University Of Georgia Research Foundation Inc, Athens GA

Investigators

Abstract

All healthy plants and animals have a resident microbiota, and the associations between bacteria and their hosts influence the development and ecological success of both partners. The research aim of this project will advance our understanding of host-bacteria interactions and will provide a novel opportunity for lab-based studies of bacterial physiology in a context that is relevant to bacterial survival in the environment -- in its natural animal host. This research exploits the tractable light organ symbiosis between the bioluminescent bacterium Vibrio fischeri and the nocturnal squid Euprymna scolopes as a model system to elucidate the functional role of bacterial bioluminescence. Theoretically, bioluminescence is energetically expensive, because it consumes oxygen and reducing power, which might otherwise be used to generate energy through respiration. Consistent with this theory, bioluminescence slows bacterial growth in culture. However, bioluminescence is common in host-associated marine bacteria like V. fischeri, and it enables V. fischeri to fully-colonize the host light organ. The research focus of this project will test possible benefits of bioluminescence in the host and reveal key differences between bacterial physiology in the host and in culture. The teaching aim of this project will broaden the learning opportunities for students in the field of host-bacteria interactions through the establishment of a new course, "Bacterial Symbioses", which integrates concepts in beneficial and pathogenic host-bacteria interactions, and through undergraduate laboratory research projects. The development of research and teaching programs that elucidate the physiological underpinnings of natural bacteria-host interactions will be pivotal in facing such current societal problems as the replacement of broad spectrum antibiotics and the (re)emergence of diseases with environmental hosts.