ID 1.13.12.7 DE firefly luciferase. AN luciferase. AN Photinus-luciferin 4-monooxygenase (ATP-hydrolyzing). AN Photinus pyralis luciferase. CA ATP + firefly D-luciferin + O2 = AMP + CO2 + diphosphate + firefly CA oxyluciferin + hnu. CC -!- The enzyme, which is found in fireflies (Lampyridae), is responsible CC for their biolouminescence. CC -!- The reaction begins with the formation of an acid anhydride between CC the carboxylic group of D-firefly luciferin and AMP, with the release CC of diphosphate. CC -!- An oxygenation follows, with release of the AMP group and formation CC of a very short-lived peroxide that cyclizes into a dioxetanone CC structure, which collapses, releasing a CO2 molecule. CC -!- The spontaneous breakdown of the dioxetanone (rather than the CC hydrolysis of the adenylate) releases the energy (about 50 kcal/mole) CC that is necessary to generate the excited state of oxyluciferin. CC -!- The excited luciferin then emits a photon, returning to its ground CC state. CC -!- The enzyme has a secondary acyl-CoA ligase activity when acting on CC L-firefly luciferin. DR Q01158, LUCI_AQULA ; Q26304, LUCI_LUCMI ; P13129, LUCI_NIPCR ; DR Q27757, LUCI_PHOPE ; P08659, LUCI_PHOPY ; //