Orientation of the pigments in the thylakoid membrane and in the isolated chlorophyll-protein complexes of higher plants. III. A quantitative comparison of the low-temperature linear dichroism spectra of thylakoids and isolated pigment-protein complexes

Abstract The dynamics of changes in the photochemical activity of photosystem II (PSII) and low-temperature spectra at 77 K in the first leaves of 11-day winter wheat plants Triticum aestivum L., as well as structural changes in chlorophyll-protein complexes (CPC) of thylakoid membranes during recovery after a short-term (20 min) heating at a temperature of 42°C, were studied. Changes in the Fv/Fm, F735/F695, and F735/F685 ratios indicate inhibition of PSII immediately after heating. Using nondenaturing electrophoresis, it was shown that the light-harvesting Chl a/b complex of PSII does not aggregate immediately after heating but after several hours, after 6 h the desagregation of CPC was observed, which was consistent with an increase in the Fv/Fm ratio upon recovery. The influence of temperature, intensity, and quality of light (white, blue, and red light) on the recovery of PSII activity and low-temperature fluorescence spectra was studied. It was concluded that the recovery is a photo-activated low-energy process, independent of photosynthesis, and the most effective in blue light.

Download Full-text

Effects of Low Temperature on Chlorophyll Protein Complexes and Regulation Capacity of Excitation Energy Distribution in Chloroplast Membrane of Cucumber

Current Research in Photosynthesis ◽

10.1007/978-94-009-0511-5_779 ◽

1990 ◽

pp. 3461-3464

Author(s):

C. H. Xu ◽

F. H. Zhao ◽

K. B. Wang ◽

D. H. Yang ◽

Y. L. Dai

Keyword(s):

Low Temperature ◽

Energy Distribution ◽

Excitation Energy ◽

Protein Complexes ◽

Chloroplast Membrane ◽

Chlorophyll Protein Complexes ◽

Chlorophyll Protein

Download Full-text

Variabilität des "light-harvesting-systems" im Zellzyklus von Chlorella fusca / Variability of the Light-Harvesting-System during the Cell Cycle of Chlorella fusca

Zeitschrift für Naturforschung C ◽

10.1515/znc-1985-1-222 ◽

1985 ◽

Vol 40 (1-2) ◽

pp. 115-121 ◽

Cited By ~ 4

Author(s):

Peter Brandt ◽

Helene Gleibs ◽

Andrea Kohne ◽

Wolfgang Wiessner

Keyword(s):

Cell Cycle ◽

Light Harvesting ◽

Higher Plants ◽

Protein Complexes ◽

Light Period ◽

Chlorella Fusca ◽

Chlorophyll Accumulation ◽

Harvesting Systems ◽

Chlorophyll Protein Complexes ◽

Chlorophyll Protein

The seven chlorophyll-protein complexes CPIa, CPI, LHCP1, LHCP2, CPa, LHCP1 and LHCP11 known in part also from the chloroplasts of higher plants were isolated from Chlorella fusca. They were characterized by their molecular weight, their absorption maxima and their ratio of chlorophyll a/chlorophyll b. The composition of the chloropyhll-protein complexes changes during the cell cycle of Chlorella fusca. The ratio of LHCP/CPI decreases at the beginning of the light period and the ratio LHCP/CPa after the 2nd hour of the light period. Both quotients increase at the 5th hour of the light period, have a maximum at the 8th hour of the light period and decrease afterwards during the second part of the cell cycle. These alterations are no reflections of chlorophyll-accumulation, but cause modifications in the organization of the thylakoids and influence the photosynthetic efficiency of Chlorella fusca. The size of the PSI- and PSII-units during the cell cycle was estimated by these changes of the LHCP/CPI- and LHCP/CPa-ratios. In addition evidence is given that the assembly of LHCP1 and LHCP2 is no simple association of the monomeric forms of LHCPI or LHCPII.

Download Full-text