CONTRIBUTIONS TO MICROBIAL BIOGEOCHEMICAL CYCLING IN MEROMICTIC LAKES BY AUXILIARY METABOLIC GENES IN BACTERIOPHAGES OF PHOTOTROPHS

Bacteriophages can carry and integrate auxiliary metabolic genes (AMGs) into the genomes of their host, redirecting energy investment of the host to facilitate lytic or lysogenic lifestyles. Many of these AMGs produce critically important changes in energy metabolism in bacteria, including photosynthesis. These phage-induced changes to metabolism can alter microbial biogeochemical cycles in the environment, particularly carbon and sulfur. Meromictic lakes are useful models for studying these processes due to the stratification of both the water column and corresponding microbial community, though few have been studied in this capacity. Here, we present the results of a metagenomic study of bacteriophages and their AMGs in two meromictic lakes: ferruginous, eutrophic Devil’s Bathtub (DBT; Rochester, NY), and euxinic, oligotrophic Fayetteville Green Lake (FGL; Syracuse, NY). We found a greater diversity of cyanobacterial taxa in DBT compared to FGL; however, a significant proportion of bacteriophages in both lakes use Synechococcus as the host cell. While Synechococcus is the primary cyanobacterial taxon in FGL, it is notable that more abundant cyanobacterial taxa in DBT did not have many or any corresponding detectable bacteriophages. Despite the considerable geochemical differences between these lakes, the overall composition of phototrophic bacteriophages. This may suggest a similar biogeochemical impact of cyanophage AMGs across aquatic systems, independent of their nutrient status.

Primary Presenter: Cassandra Marnocha, Niagara University (cmarnocha@niagara.edu)

Authors:

Alexandra Kiedrowski, Niagara University  (akiedrowski2@mail.niagara.edu)

William Edwards, Niagara University  (wje@niagara.edu)

Cassandra Marnocha, Niagara University  (cmarnocha@niagara.edu)