Circular Dichroism Spectra of System I Particles From Normal Chloroplasts and Carotenoid‐deficient Mutants of Maize

Garay, A. S.; Demeter, S.; Kovács, K.; Horváth, Gábor; Faludi-Dániel, Ágnes

doi:10.1111/j.1751-1097.1972.tb07345.x

Cited by 7 publications

(5 citation statements)

References 14 publications

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“…Upon digitonin fragmentation, the large double signal disappeared, as has already been shown with spinach chloroplasts (8). The resulting CD spectrum obtained here with bundle sheath chloroplasts resembled those found with the "quantasomes" produced by ultrasonic treatment (19), with system 1 particles of maize (6), and with spinach chloroplasts after treatment with detergents (3). Separation of the lamellae did not affect the gross characteristics of the CD spectrum of chloroplasts.…”

Section: Isolationsupporting

confidence: 52%

“…The positive signal with a maximum at about 515 nm can possibly be attributed to carotenoids with some ordered arrangement (6). The …”

Section: Isolationmentioning

confidence: 99%

“…Regarding the size of CD signals, in analogy with the anisotropy factor (5), a tentative evaluation was applied by dividing the area under CD spectrum by the area under the FALUDI-DANIEL, DEMETER, AND GARAY absorption spectrum of the chloroplasts and pigment extracts, in the spectral region of 600 to 750 nm (6). This ratio, indicating the increase of CD of chlorophylls in vivo, was much higher for the granal than for agranal chloroplasts, although the over-all chlorophyll contents were about the same (Table I).…”

Section: Isolationmentioning

confidence: 99%

“…Granum-forming regions of chloroplast lamellae have been characterized by the presence of particles on the cleavage faces of freeze-etched replicas (7,14), but the molecular architecture responsible for granum formation has not been elucidated. Circular dichroism spectroscopy of chloroplast pigments has proved to be a useful approach in studying the molecular architecture of chlorophyll dimers in solution (15), reaction centers of photosynthetic bacteria (16), bacteriochlorophyllprotein complexes (13), chlorophyll aggregates developing in greening leaves (19), isolated grana (11), and system 1 particles (6).…”

mentioning

confidence: 99%

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Circular Dichroism Spectra of Granal and Agranal Chloroplasts of Maize

Faludi-Dániel

Demeter²,

Garay³

1973

Plant Physiol.

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Granum-containing chloroplasts from mesophyil cells of maize (Zea mays L. var. MV 861) leaves exhibited circular dichroism spectra with a large double signal; peaks at 696 nm (+) and 680 nm (-). In the circular dichroism spectra obtained with agranal chloroplasts of bundle sheath cells, this large double signal is absent. Separation of grana lamellae, in a medium of low salt concentration and in KSCN solution, resulted only in a slight decrease of the amplitude, while upon treatment with digitonin the large double signal disappeared. A negative signal of the chlorophyll b peak at 654 nm was observed in the case of both granal and agranal chloroplasts, and it was not affected either by low salt or by digitonin treatment. A positive peak at about 515 nm was higher in granal than in agranal chloroplasts.Typical chloroplast lamellae consist of different regions possessing or lacking the capacity to form grana (10). The capacity of membranes to stack is important for both coupling of photosystems (1) and the prevention of chlorophyll against photooxidation (17). Granum-forming regions of chloroplast lamellae have been characterized by the presence of particles on the cleavage faces of freeze-etched replicas (7,14), but the molecular architecture responsible for granum formation has not been elucidated. Circular dichroism spectroscopy of chloroplast pigments has proved to be a useful approach in studying the molecular architecture of chlorophyll dimers in solution (15) had developed two leaves of 7 to 8 cm. Leaves were harvested in the morning in order to obtain chloroplasts depleted of starch. Granum containing chloroplasts were prepared from the mesophyll, whereas agranal chloroplasts were obtained from the bundle sheath. The isolation procedure was similar to that described by Woo et al. (22). Leaf blades were cut into strips (1 mm X 10 mm). Samples of 1 g were blended in a Virtis-45 Blendor twice for 10 sec at 20,000 rpm in 10 ml of an isotonic medium containing 0.05 M tris-HCI, pH 7.3, 0.3 M D-sorbitol, and 10 mg/l bovine serum albumin (Sigma Chemical Co.). The slurry was filtered through a sieve of about 30 ,um pore size. The filtrate contained broken mesophyll cells; the remainder consisted of the vascular bundles surrounded by the bundle sheath and a number of mesophyll cells. The latter was blended for 10 sec at 20,000 rpm in 10 ml of the isolation medium and filtered. This filtrate, containing a mixture of broken mesophyll and bundle sheath cells, was discarded. The remainder was ground in a mortar in 10 ml of the isolation medium and filtered through the microsieve. Filtrates prepared from mesophyll and bundle sheath cells were pooled at 3000g for 2 min and 20 min, respectively. The pellet from the first blending consisted of mesophyll chloroplasts, and the pellet from the grinding contained bundle sheath chloroplasts. Crosscontamination of the preparations was 3 to 5%, as tested by the electron microscope.Salt Treatments. The pellets were suspended in isolation medium or subjected to low salt or d...

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Section: Isolationsupporting

confidence: 52%

“…The positive signal with a maximum at about 515 nm can possibly be attributed to carotenoids with some ordered arrangement (6). The …”

Section: Isolationmentioning

confidence: 99%

Section: Isolationmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Circular Dichroism Spectra of Granal and Agranal Chloroplasts of Maize

Faludi-Dániel

Demeter²,

Garay³

1973

Plant Physiol.

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“…Comparison with the spectra of membrane vesicles isolated from a reaction-centre-deficient mutant has been used throughout this work to circumvent such difficulties. (Garay et al, 1972). The spectra (absorption and c.d.)…”

Section: Resultsmentioning

confidence: 99%

The contribution of the carotenoid to the visible circular dichroism of the light-harvesting antenna of Rhodospirillum rubrum

Lozano

Fernández-Cabrera

Ramı́rez

1990

Biochemical Journal

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The visible c.d. spectrum of wild-type Rhodospirillum rubrum shows positive bands [Dratz, Schultz & Sauer (1966) Brookhaven Symp. Biol. 19, 303-318] that are largely due to the B880 antenna pigments, bacteriochlorophyll a and carotenoids. The bacteriochlorophyll c.d. band was absent from the spectrum of R. rubrum G9, a mutant unable to synthesize coloured carotenoids, and could be partly restored by adding extracted carotenoids to freeze-dried membrane vesicles isolated from that mutant. Therefore it seems to arise from either bacteriochlorophyll-carotenoid interactions or bacteriochlorophyll-protein interactions that are induced by the carotenoid. The more complex carotenoid c.d. band had different shapes in native and reconstituted carotenoid-containing membranes. Such differences suggest that the optical activity of the carotenoid in the B880 antenna arises from both non-degenerate and degenerate interactions.

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Pigment Synthesis and Photosynthetic Activity in Carotenoid Deficient Mutants of Maize

Faludi-Dániel

1975

Genetic Aspects of Photosynthesis

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Circular Dichroism Spectra of System I Particles From Normal Chloroplasts and Carotenoid‐deficient Mutants of Maize

Cited by 7 publications

References 14 publications

Circular Dichroism Spectra of Granal and Agranal Chloroplasts of Maize

Circular Dichroism Spectra of Granal and Agranal Chloroplasts of Maize

The contribution of the carotenoid to the visible circular dichroism of the light-harvesting antenna of Rhodospirillum rubrum

Pigment Synthesis and Photosynthetic Activity in Carotenoid Deficient Mutants of Maize

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