Synthesis of dehydroluciferin by firefly luciferase: effect of dehydroluciferin, coenzyme A and nucleoside triphosphates on the luminescent reaction.
The formation of dehydroluciferin (L) from luciferin (LH2) in the reaction catalyzed by firefly luciferase (EC 1.13.12.7) has been studied. The E.LH2-AMP complex may follow two different pathways: towards production of light and towards the synthesis of the E.L-AMP complex. This last step has an inhibitory effect on light emission as molecules of the enzyme are trapped in a light unproductive complex. The effects of CoA and nucleoside 5'-triphosphates (NTPs) on light emission are quantitatively different. CoA combines with the L moiety of the E.L-AMP complex, yielding L-CoA, promoting liberation of free luciferase, and increasing light yield. NTP reacts with the AMP moiety of the same complex, generating adenosine(5')tetraphospho(5')nucleoside (Ap4N) and, probably, the E. L complex and scarcely increasing light production. The results are discussed in relation to previous reports, by others, on luciferase.
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Instituto de Investigaciones Biomédicas del CSIC, Universidad Autónoma de Madrid, Madrid, 28029, Spain.
Dukhovich
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Sillero
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Sillero
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MA
D000227:Adenine Nucleotides / Q000737:chemistry*; D000818:Animals; D002384:Catalysis; D003065:Coenzyme A / Q000737:chemistry*; D001517:Coleoptera / Q000201:enzymology*; D049454:Firefly Luciferin / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D007700:Kinetics; D008156:Luciferases / Q000737:chemistry*; D008163:Luminescent Measurements
D000227:Adenine Nucleotides; C107793:dehydroluciferin; D049454:Firefly Luciferin; D008156:Luciferases; D003065:Coenzyme A