Presenter: Tyler Holmes, College of Science, Chemistry
Authors: Tyler Holmes, Jacob C. Dean
Faculty Advisor: Jacob Dean, College of Science, Chemistry
Institution: Southern Utah University
Abstract: Spirulina sp. is a photosynthetic cyanobacteria, using pigments to harvest light, powering its internal processes. Each pigment has a very specific range within which it absorbs and re-emits light. These phycocyanin proteins are unique in their structure and function, evolved over millions of years to best transfer energy and support the plant’s energy needs. It is possible to introduce secondary pigments into these intricate systems to influence their absorption and fluorescence characteristics. This “bioconjugation” process and outcomes may provide us with important information about the sensitivity of the native pigment network to structural changes, or even modify the protein to absorb more energy. One such protein observed in Spirulina sp. is C-phycocyanin. C-phycocyanin has a characteristic and unique absorption pattern and disc-like protein structure. Based on its individual absorption and fluorescence spectra, we suspect that Rhodamine-B would be an advantageous energy donor into the system to potentially enhance its light capture ability. After mixing the solutions, we have established that the protein and pigment bind efficiently and likely non-selectively. The overall effect of the binding can be seen in spectral changes of the bioconjugate, but the specific mechanisms behind those changes are currently being investigated.