MS Thesis Defense - Environmental Science and Policy

MS Thesis
Department of Environmental Science and Policy
College of Science
George Mason University

Candidate: Jacob K. Mormando
Defense Date and Time: April 7, 2026 at 2:00pm
Defense Location: Zoom (registration required)
Title: Does temperature impact the growth and anatoxin-a production of the riverine cyanobacterium Microcoleus?

Thesis Director: Dr. Rosalina Stancheva Christova
Committee: Dr. Jennifer L. Salerno, Dr. Paula Furey

ABSTRACT

Microcoleus is a mat-forming, anatoxin-producing filamentous cyanobacterium that often proliferates in flowing waters. We investigated the effects of temperature on growth and anatoxin production in three monoclonal strains of Microcoleus anatoxicus, isolated from geographically distant rivers in California, Utah, and Virginia. The strains were grown at 10°C, 20°C, and 30°C for 35 days. Both low and high temperatures negatively affected specific growth rates, while anatoxin production increased under these conditions, with the strongest response observed at 30°C across all strains. These results highlight temperature-driven variability in toxin production and provide insight relevant to the management of harmful cyanobacterial blooms.