Development of a hydrogel-based biocompatible platform for studying metabolic interactions between algae and bacteria

Abstract

Metabolic interaction between algae and bacteria is an essential topic to develop algal crops as a source of biofuels and to understand nutrient cycling in ocean ecosystems. To date, studying chemical exchange between these microbial species based on molecular diffusion processes has been challenging due to a lack of an appropriate co-culture system. In this thesis, a hydrogel-based biocompatible platform is proposed to study the interaction between algae and bacteria in a systematic way. By using this platform, different species of microorganisms are physically separated each other by culturing them in individual wells, while allowing an exchange of metabolites by chemical diffusion through the nanoporous hydrogel wall. In the first chapter, I discuss ongoing efforts to understand interaction between algae and bacteria and experiments to culture algal species. In the second chapter, I introduce the hydrogel-based platform and discuss how it can be designed to incubate microorganisms with a spatially controlled biomolecular diffusion. In the final chapter, I discuss a community structure of associated bacteria co-cultured with their algal host Phaeodactylum tricornutum, which is shaped by diffusion process using the hydrogel-based platform.