Secretional luciferase of the luminous shrimp Oplophorus gracilirostris: cDNA cloning of a novel imidazopyrazinone luciferase

The deep-sea shrimp Oplophorus gracilirostris secretes a luciferase that ca talyzes the oxidation of coelenterazine to emit blue light, The luciferase (M-r approx. 106 000) was found to be a complex composed of 35 kDa and 19 k Da proteins, and the cDNAs encoding these two proteins were cloned. The exp ression of the cDNAs in bacterial and mammalian cells indicated that the 19 kDa protein, not the 35 kDa protein, is capable of catalyzing the luminesc ent oxidation of coelenterazine, The primary sequence of the 35 kDa protein revealed a typical leucine-rich repeat sequence, whereas the catalytic 19 kDa protein shared no homology with any known luciferases including various imidazopyrazinone luciferases. (C) 2000 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.