Combined experimental and theoretical study of Coelenterazine chemiluminescence in aqueous solution

• Type: Article in International Scientific Journal
• Date: 2018

Authors

Lourenco, JM (Author) Other; Joaquim C G E Esteves da Silva (Author) FCUP; da Silva, LP (Author) FCUP

Journal

Title: Journal of Luminescence

Vol. 194

Pages: 139-145

ISSN: 0022-2313

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 13 Citations

Scopus - 13 Citations

Other information

Authenticus ID: P-00N-4TB

DOI: 10.1016/j.jlumin.2017.10.025

Abstract (EN): Coelenterazine is a common substrate used by marine species in enzyme-catalyzed bioluminescent reactions, in which thermal energy is converted into light-emission. Besides bioluminescence, Coelenterazine is also known to emit chemiluminescence in aprotic solvents. We report here the study of Coelenterazine chemiluminescence in aqueous solution. Water inhibits light-emission even in mixtures with water content as low as 20%. Moreover, we provide convincing spectroscopic evidence that the presence of water affects the ground state (S-0) chemical reaction, and not the excited state processes (as chemiexcitation and the fluorescent quantum yield). However, the energetics of the S-0 chemical reaction is not affect by addition of water, which points to the inhibition being caused by the reduced lifetime of superoxide anion in water, which is an intermediate in the luminescent reactions of Coelenterazine. This finding indicates that one of the catalytic roles of bioluminescent enzymes is to extend the lifetime of this radical.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7