RESEARCH INTERESTS
The Ouellette lab uses molecular biology, biochemistry, mass spectrometry, and microbiology techniques to investigate bacteria and toxins in local waterways, with emphasis on Vibrio and Microcystis. Lab work is conducted in the Reid microbiology lab, common equipment rooms, and the Marine Science Research Institute.
Microcystis Algal Blooms
Excessive nutrients and warm waters allow Microcystis and other phytoplankton to grow rapidly to high concentrations. In addition to blocking sunlight to submerged plants, the decomposition of blooms can lead to significant declines in oxygen in the water. Both of these situations can wreak havoc on aquatic ecosystems. Furthermore, the production of liver toxins (called microcystins) by Microcystis cause another level of concern. Our lab uses ELISA, MALDI-TOF mass sepctrometery, and fluorescence to investigate these blooms and to analyze correlations between chlorophyll levels and microcystin levels as a way to predict toxicity in local waters, as well as identify areas that are particularly prone to toxic events. Kyla Siemens (JU '18; now PhD student at Purdue) wrapped up this study that biology major Rhea Derke (JU '15; now PhD student at the University of Alabama at Birmingham) carried out. Antonio Espinoza (chemistry major) is currently analyzing microcystins with MALDI-TOF mass spectrometry.
Vibrio bacteria in Sisters Creek oysters and water
Vibrio are bacteria that thrive in warm, estuarine waters. As is common with aquatic bacteria, Vibrio are found attached to particles in the water, and thus can accumulate in filter feeders such as oysters. Students in research courses and independent study at JU have detected potentially pathogenic Vibrio vulnificus and Vibrio parahaemolyticus in local waters using DNA techniques, confirming what we expected to find. Currently, biology major Janel Palomo is investigating Vibrio vulnificus, following up on a project by marine science graduate student Shelby O'Brien ('18), who used selective media and MALDI-TOF mass spectrometry to quantify and identify different species of Vibrio in oysters and water of nearby Sisters Creek, which is part of the Timucuan Ecological & Historic Preserve and was at one time a shellfish harvesting area.