TY - JOUR
T1 - Spectroscopy of photosynthetic pigment-protein complex LHCII
AU - Gruszecki, W. I.
AU - Zubik, M.
AU - Luchowski, R.
AU - Grudzinski, W.
AU - Gryczynski, Z.
AU - Gryczynski, I.
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2012/2
Y1 - 2012/2
N2 - Light-harvesting pigment-protein complex of photosystem II is the most abundant membrane protein in the biosphere, comprising more than half chlorophyll molecules. The protein plays a role of photosynthetic antenna, collecting solar radiation and transferring excitations towards the reaction centers, where electric charge separation takes place. Efficient excitation energy capture and transfer requires unique organization of the complex and unique photophysical properties of the accessory pigments: chlorophylls and carotenoids. LHCII is also a place where extremely harmful singlet oxygen may be generated, under strong illumination conditions. Several physical mechanisms have been found in LHCII, operating to protect the photosynthetic apparatus against light-induced damage, including chlorophyll triplet and singlet excitations quenching by carotenoids. In this paper we discuss the results of our recent studies, carried out with the application of several molecular spectroscopy techniques (electronic absorption, fluorescence, resonance Raman and FTIR), designed to investigate molecular mechanisms responsible for regulation of excitation density in LHCII. Among the most interesting findings are the light-induced molecular configuration changes of the LHCII-bound xanthophylls, leading to conformational rearrangements of the protein. These mechanisms are discussed in terms of excessive excitation quenching in the pigment-protein complex subjected to overexcitation. Such an activity seems to represent a vital regulatory process in the photosynthetic apparatus, at the molecular level, protecting plants against photodegradation.
AB - Light-harvesting pigment-protein complex of photosystem II is the most abundant membrane protein in the biosphere, comprising more than half chlorophyll molecules. The protein plays a role of photosynthetic antenna, collecting solar radiation and transferring excitations towards the reaction centers, where electric charge separation takes place. Efficient excitation energy capture and transfer requires unique organization of the complex and unique photophysical properties of the accessory pigments: chlorophylls and carotenoids. LHCII is also a place where extremely harmful singlet oxygen may be generated, under strong illumination conditions. Several physical mechanisms have been found in LHCII, operating to protect the photosynthetic apparatus against light-induced damage, including chlorophyll triplet and singlet excitations quenching by carotenoids. In this paper we discuss the results of our recent studies, carried out with the application of several molecular spectroscopy techniques (electronic absorption, fluorescence, resonance Raman and FTIR), designed to investigate molecular mechanisms responsible for regulation of excitation density in LHCII. Among the most interesting findings are the light-induced molecular configuration changes of the LHCII-bound xanthophylls, leading to conformational rearrangements of the protein. These mechanisms are discussed in terms of excessive excitation quenching in the pigment-protein complex subjected to overexcitation. Such an activity seems to represent a vital regulatory process in the photosynthetic apparatus, at the molecular level, protecting plants against photodegradation.
UR - http://www.scopus.com/inward/record.url?scp=84857400991&partnerID=8YFLogxK
U2 - 10.12693/APhysPolA.121.397
DO - 10.12693/APhysPolA.121.397
M3 - Article
AN - SCOPUS:84857400991
SN - 0587-4246
VL - 121
SP - 397
EP - 400
JO - Acta Physica Polonica A
JF - Acta Physica Polonica A
IS - 2
ER -