S20: Bacterial symbioses and the discovery of new molecule

Symbioses between bacteria and other organisms are commonplace and reflect the origin and evolutionary history of eukaryotes on a planet teeming with microbes.  These symbioses typically involve small molecule regulators, and the systematic exploration of these regulators provides both interesting insights into the ways conditional information is transferred and access to unusual small molecules with biological activity.  This talk will present what has been learned from two different types of symbioses: 1) the obligate mutualism between bacteria such as Photorhabdus luminescens and Xenorhabdus nematophila and their nematode hosts, Heterorhabditis bacteriophora and Steinernema carpocapsae, respectively, and  2) the intermittent symbioses, which can range from antagonistic to mutualistic, between bacteria in the Roseobacter clade and marine microalgae.