Expansion of the bioluminescence toolkit for in vivo imaging

Bioluminescence imaging is among the most popular methods for visualizing biologicalprocesses in vitro, in live cells, and even in whole organisms. At the core of this technology are enzymes (luciferases) that catalyze the oxidation of small-molecule substrates (luciferins) to release visible light. Since cells and tissues do not normally emit significant numbers of visible photons, bioluminescence provides extremely high signal-to-noise ratios, making it well-suited for sensitive imaging applications. Indeed, this technology is routinely used to monitor cell trafficking networks, gene expression patterns, and drug delivery mechanisms in vivo. Despite its remarkable versatility, bioluminescence has been largely limited to monitoring one cell type or biological feature at a time. This is because only a handful of luciferases are suitable for biological work and, of these, nearly all utilize the same substrate (D-luciferin). Retooling bioluminescence technology for multicomponent imaging requires access to larger collections of light-emitting luciferins. Such molecules could potentially provide different colors of bioluminescent light or be utilized by novel luciferase variants. Unfortunately, luciferins have been notoriously difficult to produce, owing to a lack of rapid and reliable syntheses for these richly functionalized molecules. This dissertation develops and expedient method to prepare Dluciferin, along with new classes of light-emitting analogs.