Crassostrea virginica, the eastern oyster, is considered a keystone species in New York waters and throughout the US east coast, and understanding challenges to eastern oyster restoration is a top priority of conservation groups. Like other marine species, the eastern oyster hosts a complex microbiome, including beneficial bacteria, opportunistic commensals, such as Aeromonas media, and potentially lethal pathogens such as Roseovarius crassostreae, Haplosporidium costale, and Vibrio splendidus. Detecting bacterial oyster pathogens is a challenge because of their broad diversity and because pathogens are often closely related to nonpathogenic strains. In this project, we developed a detection method using portable third generation sequencers that can capture, with high-resolution, the genetic diversity of members of the wild oyster microbiome, including potential pathogens. Oysters were collected from various restored reefs in the Hudson River Estuary system, preserved, and genomic DNA extraction was optimized for efficiency and for preservation of long strands. Full-length rRNA genes (4,200 bp) were amplified and sequenced on a Nanopore MinION system, giving high-resolution taxonomic coverage that allowed for the identification of several pathogens from these microbiomes and identification of infected individual oysters. As the project expands, we will apply this method to determine how environmental factors such as warming can impact the proliferation of pathogens at restored reefs, and try to determine thresholds for the onset of bacterial infections.

Primary Presenter: Matthew Franolich, Molloy University (mfranolich1@lions.molloy.edu)

Authors:

Joseph Benevento, Molloy University  (jbenevento@lions.molloy.edu)

Dr. Elizabeth Suter, Molloy University  (esuter@molloy.edu)