title: Synthesis of α,β-unsaturated aldehydes as potential substrates for bacterial luciferases.
abstract: Bacterial luciferase catalyzes the monooxygenation of long-chain aldehydes such as tetradecanal to the corresponding acid accompanied by light emission with a maximum at 490nm. In this study even numbered aldehydes with eight, ten, twelve and fourteen carbon atoms were compared with analogs having a double bond at the α,β-position. These α,β-unsaturated aldehydes were synthesized in three steps and were examined as potential substrates in vitro. The luciferase of Photobacterium leiognathi was found to convert these analogs and showed a reduced but significant bioluminescence activity compared to tetradecanal. This study showed the trend that aldehydes, both saturated and unsaturated, with longer chain lengths had higher activity in terms of bioluminescence than shorter chain lengths. The maximal light intensity of (E)-tetradec-2-enal was approximately half with luciferase of P. leiognathi, compared to tetradecanal. Luciferases of Vibrio harveyi and Aliivibrio fisheri accepted these newly synthesized substrates but light emission dropped drastically compared to saturated aldehydes. The onset and the decay rate of bioluminescence were much slower, when using unsaturated substrates, indicating a kinetic effect. As a result the duration of the light emission is doubled. These results suggest that the substrate scope of bacterial luciferases is broader than previously reported.
authors.affiliation: Graz University of Technology, Institute of Biochemistry, Petersgasse 12/2, 8010 Graz, Austria.
authors.forename: Eveline
authors.initials: E
authors.lastname: Brodl
authors.affiliation: Graz University of Technology, Institute of Organic Chemistry, Stremayrgasse 9, 8010 Graz, Austria.
authors.forename: Jakov
authors.initials: J
authors.lastname: Ivkovic
authors.affiliation: Graz University of Technology, Institute of Biochemistry, Petersgasse 12/2, 8010 Graz, Austria.
authors.forename: Chaitanya R
authors.initials: CR
authors.lastname: Tabib
authors.affiliation: Graz University of Technology, Institute of Organic Chemistry, Stremayrgasse 9, 8010 Graz, Austria.
authors.forename: Rolf
authors.initials: R
authors.lastname: Breinbauer
authors.affiliation: Graz University of Technology, Institute of Biochemistry, Petersgasse 12/2, 8010 Graz, Austria. Electronic address: peter.macheroux@tugraz.at.
authors.forename: Peter
authors.initials: P
authors.lastname: Macheroux
mesh_terms: D000447:Aldehydes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D048908:Aliivibrio fischeri / Q000201:enzymology*; D004305:Dose-Response Relationship, Drug; D049453:Luciferases, Bacterial / Q000037:antagonists & inhibitors* / Q000378:metabolism; D049449:Luminescence; D062105:Molecular Docking Simulation; D015394:Molecular Structure; D010776:Photobacterium / Q000201:enzymology*; D013329:Structure-Activity Relationship; D014733:Vibrio / Q000201:enzymology*
chemical_list: D000447:Aldehydes; D049453:Luciferases, Bacterial
keywords: Bacterial bioluminescence; Luciferase; Molecular docking; α,β-unsaturated aldehydes