Seminar: Karen Lloyd – University of Tennessee

UNC-CH’s Department of Marine Sciences is proud to host a seminar by alumni (2009) Karen Lloyd, Ph.D. This event is scheduled for Wednesday, January 16th, at 3:35pm in room G201 on the ground floor of Murray Hall at the University of North Carolina at Chapel Hill. This seminar will also be broadcast live to both UNC’s Institute of Marine Sciences room 222 and online via Zoom (Meeting ID: 311-406-456).

Presenter Affiliation: Associate Professor; Department of Microbiology, College of Arts & Sciences, The University of Tennessee – Knoxville

Title:  Possible extreme subsistence mechanisms of uncultured phyla in marine sediment

Abstract: It is impossible to accurately quantify the abundance of different taxonomic groups across all Earth environments. However, we approximated this by determining the distance of all 16S rRNA gene sequences in public databases to their nearest cultured relative. We found that uncultured organisms, and in particular uncultured phyla are highly abundant in all Earth environments, except the human body, where uncultured microbes are only novel at the family level or lower. In order to determine the functions of these uncultured microbes in marine sediments, we examined environmental metabolites, single cell genomes, metatranscriptomes, and environmental enzyme activity measurements to assess their functions. These communities are capable of subsisting for thousands of years with little growth. We identified mechanisms that may allow them to achieve this feat, and suggest that, although the total cell numbers decrease over time, these organisms are catabolically active and fill different ecological niches that distinguish them from better-studied high-energy ecological communities.