Grant: Research Tools and Instruments - Category 1 (<$150,000)

I am requesting funds to purchase a preparative ultracentrifuge for the fractionation of cell components, which is an essential capability for any biochemistry laboratory. Cell fractionation is a key step in studying the biochemistry of organelles, membranes or protein function. Once cells are broken apart, the contents can be separated using a variety of techniques. This proposal is focused on using an ultracentrifuge to separate cell components by using gradients composed of solutions with different densities. In this fractionation protocol, a sample is floated on top of a gradient material, placed in an ultracentrifuge and centrifuged at forces thousands of times greater than the force of gravity. This allows the cellular components to move through the gradient material at different rates based on size and/or density, depending on the gradient material used. This allows us to isolate purified cellular components that can be used to study composition and function. My research examines the molecular basis of senescence in microalgae and the role of the chlorophyll-binding proteins in regulating light-harvesting and the protection against excess light. To do this, we require an ultracentrifuge to fractionate thylakoid membranes and to separate the different protein complexes from these membranes after detergent solubilization. Ultimately my goal is to understand the strategies unicellular algae use to protect themselves from environmental stressors as they age in culture due to limiting nutrients. Understanding how unicellular algae age will be important for optimizing mass culturing strategies for biofuel or high-value bioproduct production.