TY - JOUR A1 - Lokstein, Heiko A1 - Krikunova, Maria A1 - Teuchner, Klaus A1 - Voigt, Bernd T1 - Elucidation of structure-function relationships in photosynthetic light-harvesting antenna complexes by non-linear polarization spectroscopy in the frequency domain (NLPF) JF - Journal of plant physiology : biochemistry, physiology, molecular biology and biotechnology of plants N2 - Photosynthetically active pigments are usually organized into pigment-protein complexes. These include light-harvesting antenna complexes (LHCs) and reaction centers. Site energies of the bound pigments are determined by interactions with their environment, i.e., by pigment-protein as well as pigment-pigment interactions. Thus, resolution of spectral substructures of the pigment-protein complexes may provide valuable insight into structure-function relationships. By means of conventional (linear) and time-resolved spectroscopic techniques, however, it is often difficult to resolve the spectral substructures of complex pigment-protein assemblies. Nonlinear polarization spectroscopy in the frequency domain (NLPF) is shown to be a valuable technique in this regard. Based on initial experimental work with purple bacterial antenna complexes as well as model systems NLPF has been extended to analyse the substructure(s) of very complex spectra, including analyses of interactions between chlorophylls and "optically dark" states of carotenoids in LHCs. The paper reviews previous work and outlines perspectives regarding the application of NLPF spectroscopy to disentangle structure-function relationships in pigment-protein complexes. KW - Excitonic interactions KW - Laser spectroscopy KW - Light-harvesting complex KW - Nonlinear polarization spectroscopy in the frequency domain KW - Pigment-pigment interactions Y1 - 2011 U6 - https://doi.org/10.1016/j.jplph.2010.12.012 SN - 0176-1617 VL - 168 IS - 12 SP - 1488 EP - 1496 PB - Elsevier CY - Jena ER - TY - JOUR A1 - Lokstein, Heiko A1 - Betke, Alexander A1 - Krikunova, Maria A1 - Teuchner, Klaus A1 - Voigt, Bernd T1 - Elucidation of structure-function relationships in plant major light-harvesting complex (LHC II) by nonlinear spectroscopy JF - Photosynthesis research N2 - Conventional linear and time-resolved spectroscopic techniques are often not appropriate to elucidate specific pigment-pigment interactions in light-harvesting pigment-protein complexes (LHCs). Nonlinear (laser-) spectroscopic techniques, including nonlinear polarization spectroscopy in the frequency domain (NLPF) as well as step-wise (resonant) and simultaneous (non-resonant) two-photon excitation spectroscopies may be advantageous in this regard. Nonlinear spectroscopies have been used to elucidate substructure(s) of very complex spectra, including analyses of strong excitonic couplings between chlorophylls and of interactions between (bacterio) chlorophylls and "optically dark'' states of carotenoids in LHCs, including the major antenna complex of higher plants, LHC II. This article shortly reviews our previous study and outlines perspectives regarding the application of selected nonlinear laser-spectroscopic techniques to disentangle structure-function relationships in LHCs and other pigment-protein complexes. KW - Excitonic interactions KW - Laser spectroscopy KW - Light-harvesting complex (LHC II) Y1 - 2012 U6 - https://doi.org/10.1007/s11120-011-9700-y SN - 0166-8595 VL - 111 IS - 1-2 SP - 227 EP - 235 PB - Springer CY - Dordrecht ER -