Microbial Metatranscriptomic Investigations Across Contamination Gradients within the Detroit River

Session: 15. - Environmental 'omics: New Tools for Aquatic Ecosystem Science and Management

Nick Falk, University of Windsor GLIER, [email protected]
Ken Drouillard, University of Windsor, Great Lakes Institute for Environmental Research, [email protected]
Chris Weisener, University of Windsor, [email protected]

Abstract

Microbial community composition and function are influenced by the presence and persistence of anthropogenic contaminants, yet simultaneously impose a significant level of control on their transformation and degradation. Thus, from a remediation perspective it is invaluable to understand the suite of microbial genes that are being expressed in these environments. Metatranscriptomic analysis of total bacterial and archaeal messenger RNA (mRNA) from sediments enables this level of functional investigation. The Detroit River bordering Michigan and Ontario has a complex history of industrialization, urbanization and agricultural land use, and is designated a binational Area of Concern (AOC) in the Great Lakes. Comprehensive sediment surveys and modelling have delineated the river into discrete contaminant zones based on concentrations of polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB), and metals. Building on this dataset, we have performed metatranscriptomics on sediments within low, intermediate, and high polluted sections to connect contaminant levels with total microbial gene profiles. Contamination correlated with up regulation of stress response genes and transposases, as well as unique microbial carbon metabolism signatures that are reflective of central and lower aromatic degradation pathways. Additionally, similarities in gene profiles across contaminant gradients are indicative of microbial community resilience in the face of chemical perturbations.

1. Keyword
microbiological studies

2. Keyword
environmental contaminants

3. Keyword
Detroit River

4. Additional Keyword
metatranscriptomics

5. Additional Keyword
sediments

6. Additional Keyword
PAHs