PhD student in biological oceanography focusing on understanding the various forms of phosphorus that can be used by phytoplankton.
Emily Waggoner is a 3rd year PhD Candidate in Solange Duhamel’s lab at the University of Arizona, Molecular and Cellular Biology Department.
SWOT-AdAC: Your research interests besides BioSWOT-Med
I’ve always been drawn to the ocean, spending summers at the coast as a kid. I met Dr. Solange Duhamel onboard the R/V Endeavor in 2018 and since then, I’ve been enamored by phytoplankton and how they survive in regions with little to no phosphorus for growth. My PhD work focuses on understanding the various forms of phosphorus that phytoplankton can use and the enzymes that help support this.
SWOT-AdAC: In the BioSWOT-Med cruise you will be responsible for measuring polyphosphates and organophosphates esters. What are they and why is it important to measure them?
Phosphorus is essential for cells to function and grow. In the Mediterranean Sea, where phosphate is a limiting nutrient, polyphosphates can be used as an alternative source of phosphorus for phytoplankton. Emerging pollutants, such as organophosphate esters, are present in the Mediterranean Sea and may also play a role in the phytoplankton community.
SWOT-AdAC: What instruments do you use to measure them? How do they work?
On L’Atalante, we will filter seawater for both polyphosphates and organophosphate esters, store the samples, and analyze everything back in the lab.
For polyphosphates, this includes collecting phytoplankton on a filter and measuring polyphosphate by either mass spectrometry (identifying polyphosphate by the compound mass/charge ratio), or staining with a fluorescent dye. We can also look at the polyphosphate specific to phytoplankton groups by first sorting the cells.
Organophosphate esters are collected by passing seawater through a column that retains the compounds. In the lab we can transfer the compounds to a vial which is then analyzed by coupled gas-chromatography mass spectrometry. The sample is vaporized and each compound “breaks apart.” The way each compound separates is consistent and we can use that pattern to identify which compound we’re looking at and the quantity.
Contact: Tosca Ballerini (news@swot-adac.org)