Phylogenies of Microcystin-Producing Cyanobacteria in the Lower Laurentian Great Lakes Suggest Extensive Genetic Connectivity

Abstract

Lake St. Clair is the smallest lake in the Laurentian Great Lakes system. MODIS satellite imagery suggests that high algal biomass events have occurred annually along the southern shore during late summer. In this study, we evaluated these events and tested the hypothesis that summer bloom material derived from Lake St. Clair may enter Lake Erie via the Detroit River and represent an overlooked source of potentially toxic Microcystis biomass to the western basin of Lake Erie. We conducted a seasonally and spatially resolved study carried out in the summer of 2013. Our goals were to: 1) track the development of the 2013 summer south-east shore bloom 2) conduct a spatial survey to characterize the extent of toxicity, taxonomic diversity of the total phytoplankton population and the phylogenetic diversity of potential MC-producing cyanobacteria (Microcystis, Planktothrix and Anabaena) during a high biomass event, and 3) compare the strains of potential MC-producers in Lake St. Clair with strains from Lake Erie and Lake Ontario. Our results demonstrated a clear predominance of cyanobacteria during a late August bloom event, primarily dominated by Microcystis, which we traced along the Lake St. Clair coastline downstream to the Detroit River's outflow at Lake Erie. Microcystin levels exceeded the Province of Ontario Drinking Water Quality Standard (1.5 µg L−1) for safe drinking water at most sites, reaching up to five times this level in some areas. Microcystis was the predominant microcystin producer, and all toxic Microcystis strains found in Lake St. Clair were genetically similar to toxic Microcystis strains found in lakes Erie and Ontario. These findings suggest extensive genetic connectivity among the three systems.

Community Structures of Phytoplankton with Emphasis on Toxic Cyanobacteria in an Ohio Inland Lake during Bloom Season

“…The phytoplankton phyla composition observed in this study was also found in other investigated Ohio lakes such as lake Erie [20] and other smaller lakes [6] [21]. The dominance of Cyanobacteria, which was also observed in a number of Ohio lakes [6], could be typical for summer algal blooms.…”

“…The phylogenetic similarity of potentially toxic species M. aeruginosa among Harsha Lake and other adjacent waters, such as Lake St. Clair, Lake Erie and Lake Ontario, indicates its broad presence. It should be noticed that the fragment of mcyA gene may not reflect high diversity of the amplicons as observed in previous study [20], due to the little variable region of mcyA assay included in its short sequence (230 bp). Davis et al .…”

“…aeruginosa found between this study and others, the mcyA sequences retrieved from various geographical locations including Ohio and adjacent waters using CD1 assay were compared. The Harsha Lake sequences were 99-100% identical to M. aeruginosa and were also 99% - 100% similar to those from Lower Laurentian Great Lakes [20], Lake Erie [31], Lake Ontario [32] and even Klamath River and San Francisco Bay delta [33]. Similar to the Harsha Lake sequences that were 99% - 100% identical to P. rubescens Z18, sequences from Grand lake St. Marys (OH) [34] and Lake Erie [31] were also 99-100% identical to this species.…”

What Medical Directors Need to Know about Dialysis Facility Water Management

“…However, it is possible that, in the future, the CMS may update its position, although currently there is no definitive timeline for any changes. Understanding the characteristics of the facility's source water will allow the medical director, biomedical technician, and clinical team to create a practical and effective quality assurance plan in the event that the source water is compromised because of natural or manmade disasters (Table 3) (6)(7)(8). Appropriately, any quality assurance plan should identify backup water sources for emergencies (9).…”

Neutral Evolution and Dispersal Limitation Produce Biogeographic Patterns in Microcystis aeruginosa Populations of Lake Systems

“…Miller, Beversdorf, Chaston, and McMahon (2013) and Beversdorf, Miller, and McMahon (2013) also studied this system and found spatial variability of community composition within and between lakes. Davis et al (2014) explored genetic connectivity of Microcystis aeruginosa in Lakes St. Clair, Erie and Ontario using the mcyA toxin gene. They found six groups at 99% identity that were present throughout the system, suggesting high connectivity.…”