کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10795320 1052572 2015 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Echinenone vibrational properties: From solvents to the orange carotenoid protein
ترجمه فارسی عنوان
خواص ارتجاعی اکینونون: از حلالها به پروتئین کاروتنوئید نارنجی
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک دانش گیاه شناسی
چکیده انگلیسی
Orange carotenoid protein (OCP) is a cyanobacterial photoactive protein which binds echinenone as a chromophore; it is involved in photoprotection of these photosynthetic organisms against intense illumination. In its resting state, OCP appears orange (OCPo), and turns into a red form (OCPr) when exposed to blue-green light. Here we have combined resonance Raman spectroscopy and molecular modeling to investigate the mechanisms underlying the electronic absorption properties of the different forms of OCP. Our results show that there are at least two carotenoid configurations in the OCPo, suggesting that it is quite flexible, and that the OCPo to OCPr transition must involve an increase of the apparent conjugation length of the bound echinenone. Resonance Raman indicates that this chromophore must be in an all-trans configuration in OCPo. Density functional theory (DFT) calculations, in agreement with the Raman spectra of both OCP forms, show that the OCPo to OCPr transition must involve either an echinenone s-cis to s-trans isomerization which would affect the position of its conjugated end-chain rings, or a bending of the echinenone rings which would bring them from out of the plane of the CC conjugated plane in the OCPo form into the CC plane in the OCPr form.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimica et Biophysica Acta (BBA) - Bioenergetics - Volume 1847, Issue 10, October 2015, Pages 1044-1054
نویسندگان
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