CULTIVATING, CHARACTERIZING, AND IMAGING AMMONIA OXIDIZING ARCHAEA FROM DISTINCT NORTH AMERICAN COASTAL ECOSYSTEMS

Ammonia-oxidizing archaea (AOA) play a significant role in the nitrogen cycle by consuming ammonia and producing nitrite as the first step of nitrification. Despite their recent discovery and abundance globally, very few representatives of AOA have been cultivated from the environment. This project aims to prepare a variety of cultured and enriched taxa of AOA from within Class Nitrososphaeria for imaging and to observe any physiological differences between these groups. Using enriched AOA cultures in our laboratory maintained for the last 2-12 years, selected candidates were prepared for a growth experiment and fluorescence imaging. We will further characterize these AOA cultures by identifying morphological differences between taxa obtained across varied environmental features including salinity and temperature. The primary goal of this project focuses on imaging these archaea to determine their external features, ultrastructure, and surface layer (S-layer) via Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). Our cultivated AOA that will be imaged and characterized include Nitrosarchaeum, Nitrosopumilus, and several unidentified subgroups. We hypothesize that our cultures will have distinct sizes, shapes, and exterior features (e.g., archaella), as previously cultivated soil and marine taxa appear distinct. Finally, we hope to define methodologies to characterize previously undefined ‘species’ of AOA from coastal marine ecosystems. 

Presentation Preference: Either

Primary Presenter: Lauren Sells, Department of Biology and Marine Biology (las8247@uncw.edu)

Authors:

Lauren Sells, University of North Carolina at Wilmington  (las8247@uncw.edu)

Bradley Tolar, University of North Carolina at Wilmington  (tolarb@uncw.edu)