Pigment structure in the FCP-like light-harvesting complex from Chromera velia

0464744 - BC 2017 RIV NL eng J - Journal Article
Llansola-Portoles, M.J. - Uragami, C. - Pacsal, A. - Bína, David - Litvín, Radek - Robert, B.
Pigment structure in the FCP-like light-harvesting complex from Chromera velia.
Biochimica Et Biophysica Acta-Bioenergetics. Roč. 1857, č. 11 (2016), s. 1759-1765. ISSN 0005-2728. E-ISSN 1879-2650
R&D Projects: GA ČR GBP501/12/G055
Institutional support: RVO:60077344
Keywords : Photosynthesis * Chlorophylls * Carotenoids * Light harvesting complex
Subject RIV: CE - Biochemistry
Impact factor: 4.932, year: 2016

Resonance Raman spectroscopy was used to evaluate pigment structure in the FCP-like light-harvesting complex of Chromera velia (Chromera light-harvesting complex or CLH). This antenna protein contains chlorophyll a, violaxanthin and a new isofucoxanthin-like carotenoid (called Ifx-l). We show that Ifx-l is present in two non-equivalent binding pockets with different conformations, having their (0,0) absorption maxima at 515 and 548 nm respectively. In this complex, only one violaxanthin population absorbing at 486 nm is observed. All the CLH-bound carotenoid molecules are in all-trans configuration, and among the two Ifx-l carotenoid molecules, the red one is twisted, as is the red-absorbing lutein in LHCII trimers. Analysis of the carbonyl stretching region for Chl a excitations indicates CLH binds up to seven Chl a molecules in five non-equivalent binding sites, in reasonable agreement with sequence analyses which have identified eight potential coordinating residues. The binding modes and conformations of CLH-bound pigments are discussed with respect to the known structures of LHCII and FCP. (C) 2016 Elsevier B.V. All rights reserved.
Permanent Link: http://hdl.handle.net/11104/0263517