Microbial Genomic Diversity across the Laurentian Great Lakes

Session: 16. - How can Microbial Metagenomics Inform Management of Great Lakes Ecosystems?

Justin Podowski, University of Chicago, [email protected]
Sara Paver, University of Chicago, [email protected]
Ryan Newton, University of Wisconsin-Mil, [email protected]
Maureen Coleman, University of Chicago, [email protected]

Abstract

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Microbial metagenomics can be used to reconstruct phylogeny, abundance, and biogeochemical potential of microorganisms. With an interconnected waterway that spans from shallow, eutrophic Lake Erie to deep and oligotrophic Lake Superior, the Laurentian Great Lakes provides an ecosystem uniquely suited to investigating how freshwater microbes shape biogeochemical cycles and respond to contrasting environments. We sequenced 21 metagenomes collected from the spring and summer of 2012 at several depths from stations on all five Great Lakes. We reconstructed 570 metagenome assembled genomes (>70% complete) from >1 billion paired end sequences and created a microbial tree of life for the Laurentian Great Lakes. We examined abundance of microbial taxa throughout the lakes, finding both cosmopolitan taxa present in all samples, namely the SAR11 alphaproteobacteria and the acI actinobacteria, and lake specific taxa such as Ignavibacteria detected only in Lake Superior and phototrophic Chloroflexi only appearing in Lake Erie. Using both a gene-centric and genome-centric approach, we examine how nitrification differs among lakes, and find unique ammonia and nitrite oxidizing microbes in Lake Erie.

1. Keyword
microbiological studies

2. Keyword
biogeochemistry

3. Keyword
species composition