Use of DNA Sequence Technology to Determine Sources and Sinks of Microbes in Waterways

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

Michael Sadowsky, University of Minnesota , [email protected]
Clairessa Brown, University of Minnesota, [email protected]
Chris Staley, University of Minnesota, [email protected]

Abstract

Many microbial source tracking (MST) methods use molecular marker genes targeting host-associated strains in animal or human feces. Despite their success, however, there is a lack of knowledge about the composition of fecal microbiota in several animals and issues with marker specificity and sensitivity. To overcome these problems, a DNA- and microbial community-based MST method has been developed.  In this study, we examined fecal input sources into , a Lake Superior watershed and the Mississippi River using DNA sequences and the program SourceTracker. For Lake Superior, fecal microbiome samples obtained from 12 different types of animals and wastewater effluent (n=233), were used to create a fecal taxon library and to perform community-based MST. Analysis of 319 fecal/environmental samples revealed that the microbial community in water and fecal samples were significantly different, allowing for the identification of source-specific fecal inputs. SourceTracker results indicated that fecal loading of the Lake Superior watershed was due to wastewater effluent and geese/gulls. Water microbiota in the Mississippi River were attributed to land use and anthropogenic inputs. Community-based MST methods are a useful tool to determine sources of fecal bacteria and microbial loading of waterways and may be useful to managers to establish TMDLs and BMPs. 

1. Keyword
microbiological studies

2. Keyword
species composition

3. Keyword
Lake Superior

4. Additional Keyword
DNA Sequence

5. Additional Keyword
Metagenomics

6. Additional Keyword
Microbial Source Tracking