Crystal structures of the F88Y obelin mutant before and after bioluminescence provide molecular insight into spectral tuning among hydromedusan photoproteins

Описание

Тип публикации: статья из журнала

Год издания: 2014

Идентификатор DOI: 10.1111/febs.12715

Ключевые слова: aequorin, bioluminescence, Ca2+-regulated photoprotein, coelenterazine, obelin, coelenterazine, obelin, 6 (4 hydroxyphenyl) derivative, benzene derivative, calcium ion, hydromedusan, mutant protein, oxygen, photoprotein, unclassified drug, amino acid substitution, article, calcium transport, crystal structure, fluorescence, hydrogen bond, priority journal, protein conformation, protein structure, wild type, Coelenterata, Animals, Conserved Sequence, Crystallography, X-Ray, Hydrogen Bonding, Hydrozoa, Luminescent Proteins, Models, Molecular, Mutagenesis, Site-Directed, Mutant Proteins, Spectrophotometry

Аннотация: Ca2+-regulated photoproteins are responsible for the bioluminescence of a variety of marine coelenterates. All hydromedusan photoproteins are a single-chain polypeptide to which 2-hydroperoxycoelenterazine is tightly but non-covalently bound. Bioluminescence results from oxidative decarboxylation of 2-hydroperoxycoelenterazine, genПоказать полностьюerating protein-bound coelenteramide in an excited state. The bioluminescence spectral maxima of recombinant photoproteins vary in the range 462-495nm, despite a high degree of identity of amino acid sequences and spatial structures of these photoproteins. Based on studies of obelin and aequorin mutants with substitution of Phe to Tyr and Tyr to Phe, respectively [Stepanyuk GA etal. (2005) FEBS Lett 579, 1008-1014], it was suggested that the spectral differences may be accounted for by an additional hydrogen bond between the hydroxyl group of a Tyr residue and an oxygen atom of the 6-(p-hydroxyphenyl) substituent of coelenterazine. Here, we report the crystal structures of two conformation states of the F88Y obelin mutant that has bioluminescence and product fluorescence spectra resembling those of aequorin. Comparison of spatial structures of the F88Y obelin conformation states with those of wild-type obelin clearly shows that substitution of Phe to Tyr does not affect the overall structures of either F88Y obelin or its product following Ca2+ discharge, compared to the conformation states of wild-type obelin. The hydrogen bond network in F88Y obelin being due to the Tyr substitution clearly supports the suggestion that different hydrogen bond patterns near the oxygen of the 6-(p-hydroxyphenyl) substituent are the basis for spectral modifications between hydromedusan photoproteins.

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Издание

Журнал: FEBS JOURNAL

Выпуск журнала: Vol. 281, Is. 5

Номера страниц: 1432-1445

ISSN журнала: 1742464X

Место издания: HOBOKEN

Издатель: WILEY-BLACKWELL

Персоны

  • Natashin Pavel V. (Chinese Acad Sci, Inst Biophys, Natl Lab Biomacromol, Beijing 100101, Peoples R China; Russian Acad Sci, Inst Biophys, Photobiol Lab, Siberian Branch, Krasnoyarsk 660036, Russia; Siberian Fed Univ, Inst Fundamental Biol & Biotechnol, Lab Bioluminescence Biotechnol, Krasnoyarsk, Russia)
  • Markova Svetlana V. (Russian Acad Sci, Inst Biophys, Photobiol Lab, Siberian Branch, Krasnoyarsk 660036, Russia; Siberian Fed Univ, Inst Fundamental Biol & Biotechnol, Lab Bioluminescence Biotechnol, Krasnoyarsk, Russia)
  • Lee John (Univ Georgia, Dept Biochem & Mol Biol, Athens, GA 30602 USA)
  • Vysotski Eugene S. (Russian Acad Sci, Inst Biophys, Photobiol Lab, Siberian Branch, Krasnoyarsk 660036, Russia; Siberian Fed Univ, Inst Fundamental Biol & Biotechnol, Lab Bioluminescence Biotechnol, Krasnoyarsk, Russia)
  • Liu Zhi-Jie (Chinese Acad Sci, Inst Biophys, Natl Lab Biomacromol, Beijing 100101, Peoples R China; ShanghaiTech Univ, iHuman Inst, Shanghai, Peoples R China)