Advisor:

Robert E. Gross, Ph.D., M.D. (Department of Neurosurgery, Emory University)

Committee:

Lily S. Cheung, Ph.D. (ChBE, Georgia Institute of Technology)

Kostas Konstantinidis, Ph.D. (CEE, Georgia Institute of Technology)

Bioluminescence Calcium Indicator Protein and Gold Nanoparticle-enhanced Bioluminescence

Bioluminescent proteins have been extensively used as a light emission source of many fusion proteins and have a wide range of application in bio-imaging and cell signaling studies. In our study, we focused on Gaussia luciferase (GLuc) from the marine copepod Gaussia princeps, which is the smallest known luciferase. The first part, we developed two ultrasensitive calcium sensing fusion proteins composed of a variant of GLuc, "slow-burn" Gluc (sbGLuc) and the calcium-dependent fluorescent sensor protein, GCaMP6s. Our design exhibited excellent sensitivity at physiological calcium concentration and can be explained by bioluminescence resonance energy transfer (BRET). The second part, we represented a bioluminescence enhancement strategy, which conjugates Ni-NTA (nitrilotriacetic acid) coated gold nanoparticle with 6 histidine tagged sbGLuc. One version exhibited 75% enhancement of bioluminescence compared with the non-treated sbGLuc. The new sensors together with the gold nanoparticle-enhanced bioluminescence should be useful for various studies in various fields such as neuroscience and cell biology