Special Lecture — Justin Seymour (University of Technology Sydney)

“The role of behaviour in inter-microbial relationships in the pelagic ocean”

Rather than solo travelers on the ocean’s currents, planktonic marine microbes are embedded within intricate ecological networks, whereby complex inter-species relationships can often be just as important as abiotic environmental drivers in governing microbial community composition and function. Arguably among the most important of these inter-microbial interactions are those involving phytoplankton and bacteria. These relationships can be symbiotic in nature, and often involve reciprocal exchanges of metabolites, resulting in mutual growth enhancement and sometimes ecosystem-wide biogeochemical outcomes. The physical nature of the pelagic realm, along with the specificity of chemical exchanges involved in these interactions, often means that close proximity of partner organisms will be crucial for phytoplankton-bacterial symbioses. Therefore, microbial behaviours including motility and chemotaxis will potentially be key for the establishment and maintenance of relationships. In my talk I will synthesize results derived from laboratory-based experimentation and novel in situ behavioural assays, which have provided a view into the intricate social lives of planktonic marine microbes. These studies have revealed the importance of specific chemical currencies, unique behavioural strategies and metabolic co-dependencies in shaping the microscale organisation, and potential large-scale influence, of the ocean’s microbiome.

Questions? Contact An Tran