In an attempt to explore the relationships between phosphatidylglycerol （PG） molecular species of thylakoid membrane lipids and sensitivities to chilling-induced photoinhibition, PG molecular species, D1 protein, el...In an attempt to explore the relationships between phosphatidylglycerol （PG） molecular species of thylakoid membrane lipids and sensitivities to chilling-induced photoinhibition, PG molecular species, D1 protein, electron transport activities of thylakoid membrane and the potential quantum yield （FvlFm） in rice treated under middle and low photon flux density （PFD） at 11℃ were analyzed by high performance liquid chromatography, enzyme hydrolysis, gas phase chromatography （GC） and so on. Results showed that the major molecular species of PGs in rice thylakoid membrane were 18：3/16：0, 18：3/16：1（3t）, 18：2/16：0, 18：2/16：1（3t）, 18：1/16：0, 18：1/16：1（3t）, 16：0/16：0, 16：0/16：1（3t）. There were large differences in the contents of unsaturated PG molecular species such as 18：1-3/16：0-16：1（3t） and saturated PG molecular species like 16：0/16：0-16：1（3t） among japonica cv 9516 0-9516）, japonica-indica hybrid F1 j-9516/i-SY63 （ji-95SY） and indica cv Shanyou 63 （i-SY63）. J-9516 containing higher contents of unsaturated PG molecular species was manifest in stable D1 protein contents under chill and tolerant to chill-induced photoinhibition. In contrast to j-9516, i-SY63 with lower contents of unsaturated PG molecular species, exhibited unstable D1 protein contents under chill and was sensitive to chill-induced photoinhibition, ji-95SY containing middle contents of unsaturated PG molecular species between those of j-9516 and i-SY63, exhibited mid extent of sensitivity to chill-induced photoinhibition. The losses in D1 protein also account for the inhibition in electron transport activity of thylakoid membrane and the observed decline in FvlFm. The PG molecular species that is efficient in raising chilling-resistant capacity were those containing unsaturated fatty acids, namely, unsaturated PG molecular species. These results implied that the substrate selectivity of the glycerol-3-phosphate acyltransferase in chloroplasts towards 16：0 or 18：1 displayed greatly the difference between japonica and indica rice. Itwas possible to enhance the capacity of resistance to chilling-induced photoinhibition by improving or modifying the GPAT gene.展开更多
PG constitutes 3%—5% lipids of plant thylakoid membrane.It was said that the more saturated PG in cold sensitive plant might cause phase transition of whole membrane at the chilling temperature.The differences in PG ...PG constitutes 3%—5% lipids of plant thylakoid membrane.It was said that the more saturated PG in cold sensitive plant might cause phase transition of whole membrane at the chilling temperature.The differences in PG fatty acid展开更多
The structural aspects in the interaction of phosphatidylglycerol (PG) with photosystem II (PSIl), mainly the effect of PQ on conformation and microenvironment of tyrosine residues of PSIl proteins were studied by Fou...The structural aspects in the interaction of phosphatidylglycerol (PG) with photosystem II (PSIl), mainly the effect of PQ on conformation and microenvironment of tyrosine residues of PSIl proteins were studied by Fourier transform infrared (FTIR) spectroscopy. It was found that the binding of PG to PSIl particle induces changes in the conformation and micropolarity of phenol ring in the tyrosine residues. In other words, the PG effect on the PSIl results in blue shift of the stretch vibrational band in the phenol ring from 1620 to 1500 cm-1 with the enhancement of the absorb-ance intensity. Additionally, a new spectrum of hydrogen bond was also observed. The results imply that the hydrogen-bond formation between the OH group of phenol and one of PG might cause changes in the structures of tyrosine residues in PSIl proteins.展开更多
The ettect of anionic phosphatidylglycerol (HG) on oxygen evolution in a photosystem Ⅱ (PS Ⅱ) particle depleted of Ca2+ (designated dCaPS Ⅱ) has been investigated. The major finding is the observation of a new role...The ettect of anionic phosphatidylglycerol (HG) on oxygen evolution in a photosystem Ⅱ (PS Ⅱ) particle depleted of Ca2+ (designated dCaPS Ⅱ) has been investigated. The major finding is the observation of a new role of PG in the PS Ⅱ function. That is, PG restores nearly the lost oxygen evolution in dCaPS Ⅱ particle owing to Ca2+ depletion to the levels in intact PS Ⅱ . Furthermore, there is a stimulation of oxygen-evolving activity in the dCaPSⅡ complexed with PG in the presence of exogenous CaCI2, which PG enhances increasingly oxygen evolution with increasing CaCI2 concentration. It is suggested that PG-induced oxygen evolution recovery of dCa PS Ⅱresumption of normal structure in protein by PG effect, whereas the enhancement of oxygen evolution in complex subject to CaCI2 is ascribed to the optimization of such a structure due to coordination complex formation of Ca2+ ions with PG.展开更多
基金the National Natural Science Foundation of China (30270794)Natural Science Foundation of Jiangsu Province (BK2005041, BK2007063)the Natural Science Foundation of Education Bureau of Jiangsu Province(04KJB210107, 06KJB180087).
文摘In an attempt to explore the relationships between phosphatidylglycerol （PG） molecular species of thylakoid membrane lipids and sensitivities to chilling-induced photoinhibition, PG molecular species, D1 protein, electron transport activities of thylakoid membrane and the potential quantum yield （FvlFm） in rice treated under middle and low photon flux density （PFD） at 11℃ were analyzed by high performance liquid chromatography, enzyme hydrolysis, gas phase chromatography （GC） and so on. Results showed that the major molecular species of PGs in rice thylakoid membrane were 18：3/16：0, 18：3/16：1（3t）, 18：2/16：0, 18：2/16：1（3t）, 18：1/16：0, 18：1/16：1（3t）, 16：0/16：0, 16：0/16：1（3t）. There were large differences in the contents of unsaturated PG molecular species such as 18：1-3/16：0-16：1（3t） and saturated PG molecular species like 16：0/16：0-16：1（3t） among japonica cv 9516 0-9516）, japonica-indica hybrid F1 j-9516/i-SY63 （ji-95SY） and indica cv Shanyou 63 （i-SY63）. J-9516 containing higher contents of unsaturated PG molecular species was manifest in stable D1 protein contents under chill and tolerant to chill-induced photoinhibition. In contrast to j-9516, i-SY63 with lower contents of unsaturated PG molecular species, exhibited unstable D1 protein contents under chill and was sensitive to chill-induced photoinhibition, ji-95SY containing middle contents of unsaturated PG molecular species between those of j-9516 and i-SY63, exhibited mid extent of sensitivity to chill-induced photoinhibition. The losses in D1 protein also account for the inhibition in electron transport activity of thylakoid membrane and the observed decline in FvlFm. The PG molecular species that is efficient in raising chilling-resistant capacity were those containing unsaturated fatty acids, namely, unsaturated PG molecular species. These results implied that the substrate selectivity of the glycerol-3-phosphate acyltransferase in chloroplasts towards 16：0 or 18：1 displayed greatly the difference between japonica and indica rice. Itwas possible to enhance the capacity of resistance to chilling-induced photoinhibition by improving or modifying the GPAT gene.
文摘PG constitutes 3%—5% lipids of plant thylakoid membrane.It was said that the more saturated PG in cold sensitive plant might cause phase transition of whole membrane at the chilling temperature.The differences in PG fatty acid
文摘The structural aspects in the interaction of phosphatidylglycerol (PG) with photosystem II (PSIl), mainly the effect of PQ on conformation and microenvironment of tyrosine residues of PSIl proteins were studied by Fourier transform infrared (FTIR) spectroscopy. It was found that the binding of PG to PSIl particle induces changes in the conformation and micropolarity of phenol ring in the tyrosine residues. In other words, the PG effect on the PSIl results in blue shift of the stretch vibrational band in the phenol ring from 1620 to 1500 cm-1 with the enhancement of the absorb-ance intensity. Additionally, a new spectrum of hydrogen bond was also observed. The results imply that the hydrogen-bond formation between the OH group of phenol and one of PG might cause changes in the structures of tyrosine residues in PSIl proteins.
文摘The ettect of anionic phosphatidylglycerol (HG) on oxygen evolution in a photosystem Ⅱ (PS Ⅱ) particle depleted of Ca2+ (designated dCaPS Ⅱ) has been investigated. The major finding is the observation of a new role of PG in the PS Ⅱ function. That is, PG restores nearly the lost oxygen evolution in dCaPS Ⅱ particle owing to Ca2+ depletion to the levels in intact PS Ⅱ . Furthermore, there is a stimulation of oxygen-evolving activity in the dCaPSⅡ complexed with PG in the presence of exogenous CaCI2, which PG enhances increasingly oxygen evolution with increasing CaCI2 concentration. It is suggested that PG-induced oxygen evolution recovery of dCa PS Ⅱresumption of normal structure in protein by PG effect, whereas the enhancement of oxygen evolution in complex subject to CaCI2 is ascribed to the optimization of such a structure due to coordination complex formation of Ca2+ ions with PG.
