Project II.2.3b: Characterizing communities -Bloom decay and cellular aging
Project Name: II.2.3b Characterizing communities - Bloom decay and cellular aging
Project Leads: Tawnya Peterson and Peter Zuber
Project Description
Phytoplankton blooms are characterized by high cell density, high photosynthetic activity and high oxygen production. When this is accompanied by UVR from excessive irradiance, reactive oxygen species (ROS) are generated, which can lead to macromolecular damage. The process of cellular aging in microorganisms involves the accumulation of aggregated protein, resulting from ROS-induced oxidation (carbonylation). The hypothesis that cells within blooms have increasing concentrations of aggregated, carbonylated protein over time will be tested using methodology for detecting protein oxidation. Late-growth cultures of diatoms will also be examined for accumulation of oxidation-induced protein aggregates. Controls will include cell cultures treated with translation inhibitors that have been shown to induce protein aggregation.
An interesting comparison with other phytoplankton taxa, such as dinoflagellates, will test whether protective agents produced by the cell may modulate cellular damage. Dinoflagellates produce mycosporin-like amino acids (MAAs) which have been implicated in reducing damage resulting from UVR. We will scan for these compounds by collecting cells onto glass fiber filters during harvests and measuring absorption spectra using scanning spectrophotometry.
Fit in program
The study is aligned with efforts of the Peterson/Needoba labs to examine the physiology of phytoplankton in culture. It is also relevant to studies of phytoplankton bloom dynamics being conducted by the Myrionecta group.
Outcomes
Protein carbonylation screening as an indicator of phytoplankton population health; new data on bloom aging and decay
