Thursday, October 24, 2019

Prof. Steve Techtmann, Michigan Tech
Title: Microbial Community Response to Heavy and Light Crude Oil in the Great Lakes
Host: Paradis
Abstract: Portions of the Great Lakes are at risk for oil contamination due to oil transport via pipelines. Many microorganisms have been shown to respond to released oil and use hydrocarbons as a carbon and energy source. However, very little is known about the microbial diversity of oil degrading taxa in the Great Lakes. Diverse oil types are being carried in pipelines that run in or near the Great Lakes. Chemical differences in different oil types may select for a unique set of microbial taxa. In this study we sought to characterize the microbial response to two distinct oil types and the predictability of this response across the Great Lakes. Samples of surface water were collected from seven sites in Lake Michigan, the Straits of Mackinac and Lake Superior. Bakken crude oil and Cold Lake Diluted Bitumen were amended into surface water samples. Microbial community composition was profiled across a five-week microcosm experiment using 16S rRNA gene sequencing. Our results indicated that the microbial community composition in oil-amended conditions was distinct from the control microcosms. We also observed a distinct microbial community composition in microcosms amended with different types of crude oil. These findings suggest that the Great Lakes contain a core set of taxa related to know oil-degrading microorganisms, with accessory taxa responding depending on the oil type. More recently we have begun to use machine learning to identify microbial biomarkers of different oil types as a novel tool for environmental monitoring.