Thesis Defense: Laura Fisch

The Master’s Thesis Defense of UNC Marine Sciences graduate student, Laura Fisch. Presented by the Department of Marine Sciences at UNC Chapel Hill.The location of this event will be in room G201 on the ground floor of Murray/Venable Hall on UNC-CH campus in Chapel Hill, NC and streamed live to conference room 222 at the Institute of Marine Sciences (IMS) in Morehead City, NC. This event will be held on Thursday, May 2nd at 2:00 pm. This event may be available for online viewing via Zoom.

Seminar Title: Genomic and metabolic gene characterization of bacterial communities from the Neuse River Estuarine System using long read metagenomics

Abstract: The health and productivity of estuaries is directly linked to the microbes that live in the estuary and a significant role in carbon cycling. Since these microbial communities are complex, the greatest challenge in studying them is creating a holistic description of the many working parts and working with a method to capture their complexity. Metagenomics is the recovery and sequencing of DNA from an environmental sample. This method can be applied to studying the potential of a community to drive carbon cycling by studying the carbon metabolic genes encoded in the community’s DNA. Long read sequencing technology produces DNA sequence fragments (reads) of ~ 1,000 to 50,000 base pairs. These reads are long enough to contain multiple, complete functional genes. Therefore, the sequences can be given a bacterial identity and provide a novel way to study functional roles within a complex microbial community. This study aims to understand the taxonomic identity and carbon metabolic pathways of estuarine microbial communities by applying long read sequencing technology from Oxford Nanopore Technologies to water samples collected from the Neuse River Estuary on March 8th and October 4th of 2018. For both samples, over half of the reads were assigned to the Proteobacteria phylum. Within this phylum, the were the most abundant taxa followed by Gammaproteobacteria. Pelagibacteraceae was the most abundant family for both samples. Functional marker genes for carbohydrate and aromatic compound degradation were found within the reads. Tangential to these marker genes, genes involved in similar metabolism process were found. The long reads made it possible to study spatial relationships of distal functional gene annotations and to find evidence for carbon metabolic pathways along a long read.