The origin of luciferase activity in Zophobas mealworm AMP/CoA-ligase (protoluciferase): luciferin stereoselectivity as a switch for the oxygenase activity
Beetle luciferases evolved from AMP/CoA-ligases. However, it is unclear how the new luciferase activity evolved. In order to clarify this question, we compared the luminescence and catalytic properties of a recently cloned luciferase-like enzyme from Zophobas mealworm, an AMP/CoA-ligase displaying w...
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Published in | Photochemical & photobiological sciences Vol. 9; no. 8; pp. 1111 - 1119 |
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Main Authors | , , , , , , |
Format | Journal Article |
Language | English |
Published |
Cham
Springer International Publishing
01.08.2010
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Subjects | |
Online Access | Get full text |
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Summary: | Beetle luciferases evolved from AMP/CoA-ligases. However, it is unclear how the new luciferase activity evolved. In order to clarify this question, we compared the luminescence and catalytic properties of a recently cloned luciferase-like enzyme from
Zophobas
mealworm, an AMP/CoA-ligase displaying weak luminescence activity, with those of cloned luciferases from the three main families of luminescent beetles:
Phrixthrix hirtus
railroad worm;
Pyrearinus termitilluminans
click beetle and
Photinus pyralis
firefly. The catalytic constant of the mealworm enzyme was 2-4 orders of magnitude lower than that of beetle luciferases, but 3 orders of magnitude above the non-catalyzed chemiluminescence of luciferyl-adenylate in buffer. Studies with
d
- and
l
-luciferin and their adenylates show that the luminescence reaction of the luciferase-like enzyme and beetle luciferases are stereoselective for
d
-luciferin and its adenylate, and that the selectivity is determined mainly at the adenylation step. Modelling studies showed that the luciferin binding site cavity of this enzyme is smaller and more hydrophobic than that of beetle luciferases. Therefore
Zophobas
mealworm enzyme displays true luciferase activity, keeping the attributes of an ancient protoluciferase. These results suggest that stereoselectivity for
d
-luciferin may have been a key event for the origin of oxygenase/luciferase activity in AMP/CoA-ligases, and that efficient luciferase activity may have further evolved mainly by increasing the catalytic constant of the oxidative reaction and the quantum yield of bioluminescence.
Origin of luciferase activity in AMP/CoA-ligases. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1474-905X 1474-9092 |
DOI: | 10.1039/c0pp00080a |