Abstracts

Marine bioluminescence emits light through an enzymatic reaction where the enzyme (luciferase) catalyzes the oxidation of the bioluminescent substrate, coelenterazine (CTZ). Due to the absence of drawbacks such as excitation light-induced interference, phototoxicity, photobleaching, and high background, it enables highly sensitive and non-invasive imaging. Furthermore, various applications in bioassays and bioimaging have been reported by artificially modifying and optimizing luciferases and CTZ. Our research group has successfully developed artificial marine bioluminescence systems such as bioluminescent probes that emit light upon stimulation by specific ligands and multicolor bioluminescence systems using CTZ analogues. However, these artificial bioluminescence systems have several issues. It has been observed that the bioluminescence intensity significantly decreases in multicolor bioluminescence systems that cover a range from blue to red (400-650 nm). Therefore, in this study, we focused on exploring chemical structures that exhibit high brightness and multicolor bioluminescence.We have designed and synthesized new CTZ analogues. We performed bioluminescence evaluations of these CTZ analogues with various marine luciferases. The characterization revealed that CTZ analogues luminesce with blue to orange-colored bioluminescence spectra with marine luciferase. Furthermore, they demonstrated high bioluminescence intensity with various marine luciferases, leading to the successful development of a high-brightness and multicolor bioluminescence system.