Macroorganization of chlorophyll a/b light-harvesting complex in thylakoids and aggregates: information from circular differential scattering

Garab, Győző; Faludi-Dániel, Ágnes; Sutherland, John C.; Hínd, Geoffrey

doi:10.1021/bi00407a027

Cited by 83 publications

(74 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…ref. 13) which has been shown to originate from the helically organized macrodomains of the pigment protein complexes (9,(11)(12)(13)(14). Thus, the presence of this signal in the base, middle and tip thylakoid membranes shows that qualitatively the macroorganization ofthe pigment protein complexes is very similar in all samples.…”

Section: Pigment-protein Complexesmentioning

confidence: 88%

“…It is to be emphasized that the CD signal is normalized to the Chl content of The anomalous big CD signal "accumulates" together with the LHCII in the thylakoid (8) and can also be generated upon the macroaggregation of this isolated pigment protein complex (1 1, 13). The big CD signal of chloroplasts has been shown to originate from helically organized macrodomains of the pigment-protein complexes (9,11,14). Thus, the fluctuations in the amplitude of the principal CD bands can be accounted for by changes in the macroorganization of the pigment-protein complexes.…”

Section: Pigment-protein Complexesmentioning

confidence: 99%

“…LHCII is of paramount importance in maintaining the characteristic granal stacking ofthylakoids. As indicated by recent macroscopic and microscopic CD and circular differential scattering measurements LHCII is assembled into large helically organized elastic macroarrays in the granum (8,9,11,14). LHCII plays an important role both in short-and longterm adaptational processes (1).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Diurnal Fluctuations in the Content and Functional Properties of the Light Harvesting Chlorophyll a/b Complex in Thylakoid Membranes

Busheva¹,

Garab²,

Liker³

et al. 1991

Plant Physiol.

View full text Add to dashboard Cite

Diurnal fluctuations were observed in the content and some structural and functional properties of the light-harvesting chlorophyll (Chi) a/b pigment-protein complex of photosystem 11 (LHCII) in young developing wheat (Triticum aestivum) leaves grown under 16 hours light/8 hours dark illumination regime. The fluctuations could be correlated with the diumal oscillation in the level of mRNA for LHCII. The most pronounced changes occurred in the basal segments of the leaves. They were weaker or hardly discernible in the middle and tip segments. As judged from the diurnal variations of the Chl-a/Chl-b molar ratio, the LHCII content of the thylakoid membranes peaked around 2 pm. This can be accounted for by the cumulative effect of the elevated level of mRNA in the morning and early afternoon. In the basal segment, the extent of the fluctuation in the LHCII content was approximately 25%, as determined from gel electrophoresis ("green gels"). The amplitude of the principal bands of the circular dichroism (CD) spectra of isolated chloroplasts paralleled the changes in the LHCII content. Our circular dichroism data suggest that the newly synthesized LHCII complexes are incorporated into the existing helically organized macrodomains of the pigmentprotein complexes or themselves form such macrodomains in the thylakoid membranes. Chl-a fluorescence induction kinetics also showed diumal variations especially in the basal segments of the leaves. This most likely indicates fluctuations in the ability of membranes to undergo "state transitions." These observations suggest a physiological role of diurnal rhythm of mRNA for LHCII in young developing leaves.The light-harvesting Chl a/b pigment-protein complex of PSII (LHCII3) is the predominant integral protein complex of 'This work was supported by grants OKKFT (Tt) 222/1988 and 56/1986 from the National Foundation of Technical Development (Hungary).

show abstract

Section: Pigment-protein Complexesmentioning

confidence: 88%

Section: Pigment-protein Complexesmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Diurnal Fluctuations in the Content and Functional Properties of the Light Harvesting Chlorophyll a/b Complex in Thylakoid Membranes

Busheva¹,

Garab²,

Liker³

et al. 1991

Plant Physiol.

View full text Add to dashboard Cite

show abstract

“…Changes in PsbS Level Are Associated with Altered Organization of LHCII⅐PSII in Grana Membranes-CD spectroscopy was used to investigate the macro-organization of the thylakoid membranes in vivo (19,32). Excitonic CD bands arising from the short range interactions of the chromophores at (Ϫ) 653 nm, (ϩ) 435 nm, and (ϩ) 448 nm represent the smaller peaks in the spectrum (Fig.…”

Section: ϩmentioning

confidence: 99%

The PsbS Protein Controls the Organization of the Photosystem II Antenna in Higher Plant Thylakoid Membranes

Kiss

Ruban

Horton

2008

Journal of Biological Chemistry

170

128

View full text Add to dashboard Cite

The PsbS subunit of photosystem II (PSII) plays a key role in nonphotochemical quenching (NPQ), the major photoprotective regulatory mechanism in higher plant thylakoid membranes, but its mechanism of action is unknown. Here we describe direct evidence that PsbS controls the organization of PSII and its light harvesting system (LHCII). The changes in chlorophyll fluorescence amplitude associated with the Mg 2؉ -dependent restacking of thylakoid membranes were measured in thylakoids prepared from wild-type plants, a PsbS-deficient mutant and a PsbS overexpresser. The Mg 2؉ requirement and sigmoidicity of the titration curves for the fluorescence rise were negatively correlated with the level of PsbS. Using a range of PsbS mutants, this effect of PsbS was shown not to depend upon its efficacy in controlling NPQ, but to be related only to protein concentration. Electron microscopy and fluorescence spectroscopy showed that this effect was because of enhancement of the Mg 2؉ -dependent re-association of PSII and LHCII by PsbS, rather than an effect on stacking per se. In the presence of PsbS the LHCII⅐PSII complex was also more readily removed from thylakoid membranes by detergent, and the level of PsbS protein correlated with the amplitude of the psi-type CD signal originating from features of LHCII⅐PSII organization. It is proposed that PsbS regulates the interaction between LHCII and PSII in the grana membranes, explaining how it acts as a pH-dependent trigger of the conformational changes within the PSII light harvesting system that result in NPQ.Light harvesting antennae in plant photosynthesis increase the rate at which absorbed photons excite the photosynthetic reaction centers. In the case of photosystem II (PSII) 3 in higher plants, light harvesting is carried out by a complex assembly of chlorophyll protein antenna complexes (LHCII) located in the grana membranes of the chloroplast (1). The main components are trimeric LHCIIb and monomeric CP24, CP26, and CP29. These are associated together with the dimeric PSII reaction center core complexes to form LHCII⅐PSII supercomplexes (2). The minimal unit of the supercomplex comprises two cores (C 2 ) and two strongly bound LHCIIb trimers (S 2 ), together with two copies of CP26 and CP29, referred to as the C 2 S 2 LHCII⅐PSII supercomplex (3). Two further trimers bound with moderate strength (M 2 ) together with CP24 make up the most predominant supercomplex, C 2 S 2 M 2 . LHCII⅐PSII supercomplexes are segregated from photosystem I, associating together in the lateral plane of the thylakoid membrane, sometimes forming highly ordered semi-crystalline domains. Transverse associations between the outer stromal surfaces of these proteins result in membrane appression and the characteristic grana stack. Although this highly conserved macro-organization of the PSII antenna has been rationalized in terms of efficient capture and utilization of light (4), it can be argued that it is the enabled structural and functional flexibility that is probably more important. Changes ...

show abstract

“…Chloroplasts were isolated from pea (Pisum sativum) leaves grown in a greenhouse by a method described earlier (Garab et al 1988a), and were suspended in a reaction medium containing 30 mM Tricine (pH 7.6), 5 mM MgCl 2 and 300 mM sorbitol. Subchloroplast particles, fragments containing a few grana, were obtained by sonication and differential centrifugation (Jacobi 1971); they were resuspended in the same reaction medium.…”

Section: Methodsmentioning

confidence: 99%

Alignment of biological microparticles by a polarized laser beam

et al. 2005

View full text Add to dashboard Cite

The optical alignment of biological samples is of great relevance to microspectrometry and to the micromanipulation of single particles. Recently, Bayoudh et al. (J. Mod. Opt. 50:1581-1590 have shown that isolated, disk-shaped chloroplasts can be aligned in a controlled manner using an in-plane-polarized Gaussian beam trap, and suggested that this is due to their nonspherical shape. Here we demonstrate that the orientation of various micrometer-sized isolated biological particles, trapped by optical tweezers, can be altered in a controlled way by changing the plane of linear polarization of the tweezers. In addition to chloroplasts, we show that subchloroplast particles of small size and irregular overall shape, aggregated photosynthetic lightharvesting protein complexes as well as chromosomes can be oriented with the linearly polarized beam of the tweezers. By using a laser scanning confocal microscope equipped with a differential polarization attachment, we also measured the birefringence of magnetically oriented granal chloroplasts, and found that they exhibit strong birefringence with large local variations, which appears to originate from stacked membranes. The size and sign of the birefringence are such that the resulting anisotropic interaction with the linearly polarized laser beam significantly contributes to the torque orienting the chloroplasts.

show abstract

Macroorganization of chlorophyll a/b light-harvesting complex in thylakoids and aggregates: information from circular differential scattering

Cited by 83 publications

References 36 publications

Diurnal Fluctuations in the Content and Functional Properties of the Light Harvesting Chlorophyll a/b Complex in Thylakoid Membranes

Diurnal Fluctuations in the Content and Functional Properties of the Light Harvesting Chlorophyll a/b Complex in Thylakoid Membranes

The PsbS Protein Controls the Organization of the Photosystem II Antenna in Higher Plant Thylakoid Membranes

Alignment of biological microparticles by a polarized laser beam

Contact Info

Product

Resources

About