Molecular mechanism of Symplectoteuthis bioluminescence—Part 4: Chromophore exchange and oxidation of the cysteine residue |
| |
Institution: | 1. Laboratory of Biochemistry, Faculty of Science, Kochi University, Kochi 780-8520, Japan;2. Department of Zoology, National Museum of Nature and Science, Tsukuba 305-0005, Japan;3. Faculty of Geo-environment Science, Rissho University, Magechi 1700, Kumagaya 360-0194, Japan |
| |
Abstract: | Symplectin is one of the few photoproteins, which forms covalent bonds with the dehydro-coelenterazine (DCL) at the binding sites and the active site. This binding takes place through the SH’s of the cysteine residues via conjugate addition reaction. This photoprotein contains the chromophore molecules at the binding cites first, and then moves to the active cite Cys-390 for the luminescence. The current study focuses on these dynamic aspects of the chromophore using the natural photoprotein by analyzing the fluorescence changing of the DCL chromophores analogs with 8-(4′-methoxyphenyl)- or 8-(2′-naphthyl)-group and 2-(2′,4′-difluorophenyl)-group. Exchanges of these chromophores were monitored the fluorescence at slightly acidic media and also from the luminescence function observed at the optimum pH 7.8. The non-fluorescent naphthyl analogs was even proven to make the covalent bond formation at pH 6.0 and evidently to obtain the corresponding luminescent product amide by liquid chromatographic detection from the spent solutions. |
| |
Keywords: | Bioluminescence Coelenterazine Photoprotein |
本文献已被 ScienceDirect 等数据库收录! |
|