Structure, Mechanism, and Mutation of Bacterial Luciferase

Abstract

: Bacterial luciferase is a flavin-dependent monooxygenase found in bioluminescent bacteria. The enzyme catalyzes a light-emitting reaction by using reduced flavin, long chain aldehyde, and oxygen as substrates and yields oxidized flavin, carboxylic acid, and water as products with concomitant emission of blue-green light around 485-490 nm. The enzyme is a heterodimer consisting of two homologous subunits, designated as the α- and β-subunits. The reactive reaction center is located in the α-subunit, whereas the β-subunit is required for maintaining the active conformation of the α-subunit. The enzyme reaction occurs through the generation of a reactive C4a-oxygenflavin adduct, presumably C4a-peroxyflavin, before the light-emitting species is generated from the decomposition of an adduct between the C4a-peroxyflavin and the aldehyde. Because the luciferase reaction generates light, the enzyme has the potential to be used as a bioreporter for a wide variety of applications. With the recent invention of the fusion enzyme that can be expressed in mammalian cells, future possibilities for the development of additional bioreporter applications are promising.

Keywords: Bacterial luciferase; Enzyme kinetics; Enzyme mechanism; Flavin-dependent monooxygenase; Mutagenesis.