Search results for "chlorophyll b"
showing 10 items of 51 documents
Recombinant water-soluble chlorophyll protein from Brassica oleracea var. Botrys binds various chlorophyll derivatives.
2003
A gene coding for water-soluble chlorophyll-binding protein (WSCP) from Brassica oleracea var. Botrys has been used to express the protein, extended by a hexahistidyl tag, in Escherichia coli. The protein has been refolded in vitro to study its pigment binding behavior. Recombinant WSCP was found to bind two chlorophylls (Chls) per tetrameric protein complex but no carotenoids in accordance with previous observations with the native protein [Satoh, H., Nakayama, K., Okada, M. (1998) J. Biol. Chem. 273, 30568-30575]. WSCP binds Chl a, Chl b, bacteriochlorophyll a, and the Zn derivative of Chl a but not pheophytin a, indicating that the central metal ion in Chl is essential for binding. WSCP …
Protein and solvent dynamics of the water-soluble chlorophyll-binding protein (WSCP)
2015
This study presents quasielastic neutron scattering data of the water-soluble chlorophyll-binding protein (WSCP) and the corresponding buffer solution at room temperature. The contributions of protein and buffer solution to the overall scattering are carefully separated. Otherwise, the fast water dynamics dominating the buffer contribution is likely to mask the slow protein dynamics. In the case of WSCP, the protein scattering can be described by two contributions: i) internal protein dynamics represented by a diffusion in a sphere with an average radius of 2.7 u A and ii) global (Brownian) diffusion of the WSCP macromolecule with an upper limit for the translational diffusion coefficient o…
Identification of N- and C-terminal Amino Acids of Lhca1 and Lhca4 Required for Formation of the Heterodimeric Peripheral Photosystem I Antenna LHCI-…
2002
Apoproteins of higher plant light-harvesting complexes (LHC) share considerable amino acid sequence identity/similarity. Despite this fact, they occur in different oligomeric states (i.e., monomeric, dimeric, and trimeric). As a step toward understanding the underlying structure requirements for different oligomerization behavior, we analyzed whether amino acids at the N- and C-termini of Lhca1 and Lhca4 are involved in the formation of the heterodimeric LHCI-730. Using altered proteins produced by deletion or site-directed mutagenesis for reconstitution, we were able to identify amino acids required for the assembly of LHCI-730. At the N-terminus of Lhca1, W4 is involved in heterodimerizat…
Ultrafast excitation dynamics of low energy pigments in reconstituted peripheral light-harvesting complexes of photosystem I
2000
AbstractUltrafast dynamics of a reconstituted Lhca4 subunit from the peripheral LHCI-730 antenna of photosystem I of higher plants were probed by femtosecond absorption spectroscopy at 77 K. Intramonomeric energy transfer from chlorophyll (Chl) b to Chl a and energy equilibration between Chl a molecules observed on the subpicosecond time scale are largely similar to subpicosecond energy equilibration processes within LHCII monomers. However, a 5 ps equilibration process in Lhca4 involves unique low energy Chls in LHCI absorbing at 705 nm. These pigments localize the excitation both in the Lhca4 subunit and in LHCI-730 heterodimers. An additional 30–50 ps equilibration process involving red …
Pigment-pigment interactions and secondary structure of reconstituted algal chlorophyll a/b-binding light-harvesting complexes of Chlorella fusca wit…
1995
Earlier we have shown by in vitro reconstitution experiments that the pigment composition of the chlorophyll alb-binding light-harvesting complex of the green alga Chlorella fusca could be altered in a relatively broad range (Meyer and Wilhelm 1993). In this study we used these reconstituted complexes of different pigment loading to analyze the excitonic interactions between the pigment molecules and the secondary structure by means of circular dichroism spectra in the visible and the far UV spectral regions, respectively. We found that, in contrast to the expectations, the pigment composition and pigment content hardly affected the circular dichroism spectra in the visible spectral region.…
Water-depth effects in photosynthetic pigment content of the benthic algae Dictyota dichotoma and Udotea petiolata
1981
Abstract The effect of water depth on the light-harvesting pigments contents in Dictyota dichotoma (Hudson) Lamouroux and Udotea petiolata (Turra) Borgesen was studied. Both species showed higher photosynthetic-pigments contents with increased depth or shade. The ratios of chlorophyll c /chlorophyll a and chlorophyll b / chlrophyll a in D. dichotoma and U. petiolata were lower in light-exposed samples. In D. dichotoma , the ratios of fucoxanthin to chlorophyll a increased with depth or shade; however, it is worth noting that the 0 m (sun) samples showed the highest values. On the other hand, total carotenoids to chlorophyll a ratios in U. petiolata increased with depth.
Pigment composition of PS II pigment protein complexes purified by anion exchange chromatography. identification of xanthophyll cycle pigment binding…
1997
Summary The pigment composition of the chlorophyll binding proteins of Photosystem II (PS II) of spinach ( Spinacea oleracea L.) has been determined using sucrose gradient ultracentrifugation, anion exchange chromatography and HPLC based pigment analysis. The xanthophyll cycle pigments violaxanthin, antheraxanthin and zeaxanthin were exclusively found in the proteins of the outer PS II antenna, with the highest amounts being present in the minor chlorophyll alb binding proteins CP 29 and CP 26. PS II core particles containing the reaction centre proteins D1, D2, cytochrome b 559 and the proteins of the inner antenna CP 47 and CP 43 bind β-carotene as the only carotenoid. The presence of the…
Protochlorophyllide Reduction: Mechanisms and Evolution¶
2007
Protochlorophyllide (Pchlide) reductases are key enzymes in the process of chlorophyll biosynthesis. In this review, current knowledge on the molecular organization, substrate specificity and assembly of the light-dependent reduced nicotinamide adenine dinucleotide phosphate:Pchlide oxidoreductases are discussed. Characteristics of light-independent enzymes are also described briefly, and the possible reasons for the selection of light-dependent enzymes during the course of evolution are discussed.
Chapter 16 Folding and Pigment Binding of Light-Harvesting Chlorophyll a/b Protein (LHCIIb)
2010
The major light-harvesting chlorophyll a/b protein (LHCIIb) is one of the most abundant proteins of the chloroplast in green plants. It contains roughly half of the chlorophylls involved in photosynthesis, and exhibits an unusual ability to self-organize in vitro. Simply mixing the apoprotein, native or recombinant, with its pigments, chlorophyll a, chlorophyll b, and xanthophylls, in detergent solution, suffices to trigger protein folding and the assembly of about 18 pigments in their correct binding sites. A study of the mechanism of this self-organization seems worthwhile since (1) our knowledge about membrane protein folding is scarce compared to what we know about the folding of water-…
Chlorophyll content in senescent Pelargonium graveolens leaves
2019
Pelargonium graveolens należy do rodziny Geraniaceae. Roślina ta jest aromatycznym, owłosionym krzewem, sięgającym 1,2 metra wysokości i osiągającym 1 m szerokości. Jej liście są mocno powcinane, miękkie w dotyku i wydzielają intensywny zapach, natomiast kwiaty są małe, zwykle różowe, zebrane w baldachy. Ojczyzną P. graveolens jest Afryka Południowa, ale uprawia się ją obecnie w wielu krajach świata, np. wyspie Reunion, Egipcie, Rosji, Chinach czy Maroko, głównie z przeznaczeniem na produkcję olejku eterycznego. Wykorzystywany jest on w wielu gałęziach przemysłu, m.in. perfumiarstwie, kosmetyce, przemyśle spożywczym czy medycynie. Dane literaturowe pokazują, że o kondycji całej rośliny świa…