ZfN: Search Results

1	Author	E. Interschick-Niebler, H. K. Lichtenthaler	Requires cookie*
	Title	Partition of Phylloquinone Kx between Digitonin Particles and Chlorophyll-Proteins of Chloroplast Membranes from Nicotiana tabacum
	Abstract	The partition of phylloquinone (vitamin K J, o f chlorophylls a and b and of the two main carotenoids, /?-carotene and lutein, in subthylakoid particles (digitonin treatment) and chlorophyll protein complexes (sodium dodecylsulfate polyamide-gel electrophoresis) isolated from tobacco chloroplasts (Nicotiana tabacum L.) is described. 1. The "light particle" fractions (S 90000, S 150000) of digitonin fragmented chloroplasts are enriched in CP I and contain a higher proportion o f phylloquinone, chorophyll a and /?-carotene as compared to whole chloroplasts. This is visualized by high values for the ratio a/b (6 -8) and for /?-carotene/lutein (1.7) as well as about 3 mol of Kx per 100 mol o f total chlorophyll. The "heavy digitonin particle" fraction (10000 x g sediment), in turn, contains a higher proportion of chlorophyll b and lutein, but a lower level of phylloquinone than whole chloroplasts. 2. The chlorophyll a-protein CP I o f pigmentsystem I, isolated by preparative gel electro phoresis using 0.5% and 4% SDS, is characterized by a stable level of phylloquinone (1 mol Kt per 100 mol o f total chlorophyll), high chlorophyll a/b ratios (7 -1 0) and high values for ß-carotene/lutein (~ 6.0). The light-harvesting chlorophyll a/b-protein LHCP o f photosystem II (chlorophyll a/b = 1.1 — 1.5, ^-carotene/lutein = < 0.1) contains either low amounts of phylloquinone (0.5% SDS) or only trace amounts o f Kj (4% SDS). The free pigment fraction (FP) contains at 0.5% SDS 57% of the total phylloquinone of thylakoid membranes. At 4% SDS the K? amount in the free pigment fraction increases to 84%. 3. The phylloquinone partition studies in digitonin particles and SDS chlorophyll proteins indicate that there exist at least two localization sites for phylloquinone Kj in the photosynthetic membrane. The CP I complex and a second site, presumably near photosystem II (CPa?).
	Reference	Z. Naturforsch. 36c, 276 (1981); received January 131981
	Published	1981
	Keywords	Phylloquinone, Thylakoid Composition, Chlorophyll-Proteins, Chlorophyll a/b Ratio, Carotenoids, Digitonin Particles
	Similar Items	Find
	DEBUG INFO
	TEI-XML for	default:Reihe_C/36/ZNC-1981-36c-0276.pdf
	Identifier	ZNC-1981-36c-0276
	Volume	36

2	Author	H. K. Lichtenthaler, G. Burkard, G. Kuhn, U. Prenzel	Requires cookie*
	Title	Light-Induced Accumulation and Stability of Chlorophylls and Chlorophyll-Proteins during Chloroplast Development in Radish Seedlings
	Abstract	Illumination of 3 day old etiolated radish seedlings with continuous white light results in a progressive accumulation o f chlorophyll a and b. Both pigments are bound in a different way to the thylakoid chlorophyll-proteins, which appear parallel to the formation of chlorophylls. By applying the SDS-PAGE method to SDS-digested chloroplasts, it was possible to show that the chloroplasts of radish cotyledons contain the typical chlorophyll proteins LHCPi_ 3, CPa, CPI and CPIa which have been found in other plants. Between LHCPj and CPI an additional chlorophyll protein is detected with the spectral properties of a LHCP; it is termed here LHCPy. When the green plants are transferred to continuous darkness, chlorophylls and the chloro-phyll-proteins are progressively degraded. At an early stage of greening chlorophyll b is destroyed at a much higher rate in darkness than chlorophyll a, which yields high chlorophyll a/b ratios. This is paralleled by a faster decrease in the level of the corresponding chloro phyll a/b-protein LHCP3 than of CPI. At a later stage of greening, after the end o f the logarithmic chlorophyll accumulation, the chlorophylls a and b and also the LHCP3 and CPI are destroyed in continuous darkness at equal rates; the a/b ratios and the LHCP3/CPI ratios are then little different from the light control. The data indicate that at an early stage o f greening the light-harvesting chlorophyll a/b-protein LHCPj is less stable than the other chlorophyll-proteins (CPI, CPIa, CPa), which contain pre dominantly chlorophyll a. The ratio chlorophyll a to /?-carotene (a/c ratio) of CPIa, CPI and CPa is about 10, while that of the LHCPj_ 3 is found to be between 150 to 300. We therefore propose using the a/c ratio to define the chlorophyll-proteins which, besides the absorption spectra, is the most suitable parameter.
	Reference	Z. Naturforsch. 36c, 421 (1981); received March 17 1981
	Published	1981
	Keywords	Chlorophyll a/b ratio, Chlorophyll Degradation, Chlorophyll-Proteins, Chloroplast Development, Stability of Chlorophylls
	Similar Items	Find
	DEBUG INFO
	TEI-XML for	default:Reihe_C/36/ZNC-1981-36c-0421.pdf
	Identifier	ZNC-1981-36c-0421
	Volume	36