Dr. Erin Bertrand
Assistant Professor
Dept. of Biology and Canada Research Chair in Microbial Proteomics
Dalhousie University
Marine phytoplankton are responsible for roughly half of global net primary production, support marine food webs and play critical roles in the global carbon cycle. Phytoplankton often require exogenous sources of specific organic and organometallic micronutrients for growth; these compounds appear to originate largely from co-occurring microbial communities. In some cases, the availability of these compounds can limit the growth of phytoplankton or drive changes in community composition. The most well-characterized examples in marine systems are cobalamin (vitamin B12) and thiamine (vitamin B1). Recent developments suggest that there are a series chemical transformations of micronutrient-related compounds, conducted by different, co-occurring marine microbial groups, which result in a broad chemical repertoire of nutritional factors that can support primary production. This chemical repertoire is poorly characterized and not currently predictable from genomic information. Here we’ll explore two specific examples of these interactive, microbially- mediated chemical transformations of micronutrients and present hypotheses about the key microbial groups involved. We will then examine proteomic and transcriptomic approaches to identify and quantify the role of these micronutrients and their transformations in sustaining marine primary production in the changing Northwest Atlantic and Southern Ocean. We’ll conclude by discussing implications for future ocean carbon cycling and human access to nutrition from the sea.
Polycom availability with Darling Marine Center, Gulf of Maine Research Institute, and Bigelow Laboratories
Host: Aaron Strong (aaron.strong@maine.edu)