Jump to main content
Jump to site search


The interaction of C-terminal Tyr208 and Tyr13 of the first α-helix ensures a closed conformation of ctenophore photoprotein berovin

Author affiliations

Abstract

Light-sensitive Ca2+-regulated photoprotein berovin is responsible for the bioluminescence of the ctenophore Beroe abyssicola. It shares many properties of hydromedusan photoproteins although the degree of identity of its amino acid sequence with those of photoproteins is low. There is a hydrogen bond between C-terminal Pro and Arg situated in the N-terminal α-helix of hydromedusan photoproteins that supports a closed conformation of the internal cavity of the photoprotein molecule with bound 2-hydroperoxycoelenterazine. The C- and N-terminal hydrogen bond network is necessary to properly isolate the photoprotein active site from the solvent and consequently to provide a high quantum yield of the bioluminescence reaction. In order to find out which berovin residues perform the same function we modified the N- and C-termini of the protein by replacing or deleting various amino acid residues. The studies on berovin mutants showed that the interaction between C-terminal Tyr208 and Tyr13 localized in the first α-helix of the photoprotein is important for the stabilization and proper orientation of the oxygenated coelenterazine adduct within the internal cavity as well as for supporting the closed photoprotein conformation. We also suggest that the interplay between Tyr residues in ctenophore photoproteins occurs rather through the π–π interaction of their phenyl rings than through hydrogen bonds as in hydromedusan photoproteins.

Graphical abstract: The interaction of C-terminal Tyr208 and Tyr13 of the first α-helix ensures a closed conformation of ctenophore photoprotein berovin

Back to tab navigation

Article information


Submitted
06 Nov 2019
Accepted
27 Jan 2020
First published
28 Jan 2020

Photochem. Photobiol. Sci., 2020, Advance Article
Article type
Paper

The interaction of C-terminal Tyr208 and Tyr13 of the first α-helix ensures a closed conformation of ctenophore photoprotein berovin

L. P. Burakova, E. V. Eremeeva and E. S. Vysotski, Photochem. Photobiol. Sci., 2020, Advance Article , DOI: 10.1039/C9PP00436J

Social activity

Search articles by author

Spotlight

Advertisements