Modification of pigment composition in the isolated reaction center of photosystem II

Gall, Bernhard; Zehetner, Andrea; Scherz, Avigdor; Scheer, Hugo

doi:10.1016/s0014-5793(98)00956-9

Cited by 19 publications

(28 citation statements)

References 41 publications

(45 reference statements)

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“…Overall, the Chl CD of WT Chlamydomonas RCs (Fig. 4) resembles those from other sources (49,(52)(53)(54)(55)(56)(57), with positive chirality peaking at 681 nm and a negative lobe, around 669 nm. The red edge (above 681 nm) of the positive lobe is believed to be an excitonic band associated with P680 (58-60).…”

Section: Resultsmentioning

confidence: 64%

Functional asymmetry of photosystem II D1 and D2 peripheral chlorophyll mutants of Chlamydomonas reinhardtii

Wang

Gosztola

Ruffle

et al. 2002

Proc. Natl. Acad. Sci. U.S.A.

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The peripheral accessory chlorophylls (Chls) of the photosystem II (PSII) reaction center (RC) are coordinated by a pair of symmetryrelated histidine residues (D1-H118 and D2-H117). These Chls participate in energy transfer from the proximal antennae complexes (CP43 and CP47) to the RC core chromophores. In addition, one or both of the peripheral Chls are redox-active and participate in a low-quantum-yield electron transfer cycle around PSII. We demonstrate that conservative mutations of the D2-H117 residue result in decreased Chl fluorescence quenching efficiency attributed to reduced accumulation of the peripheral accessory Chl cation, Chl Z ؉ . In contrast, identical symmetry-related mutations at residue D1-H118 had no effect on A mong the photosynthetic organisms, there are two different, quinone-type photosynthetic reaction centers (RCs): the oxygenic type present in chloroplasts and cyanobacteria (photosystem II, PSII) and the nonoxygenic type (bacterial reaction center, BRC) as typified by that in purple-sulfur photosynthetic bacteria (for reviews, see refs. 1 and 2). In 1984, the crystal structure of the Rhodopseudomonas viridis BRC was determined at 3-Å resolution by Deisenhofer et al. (3). It soon was recognized that the L and M polypeptides of the BRC had substantial amino acid sequence similarity with the PSII D1 and D2 proteins, respectively. Early models of the D1 and D2 proteinfolding topologies indicated that the PSII D1 and D2 polypeptides were structurally analogous to the L and M subunits (3-8). These models of the PSII RC polypeptides and their associated cofactors were verified by electron and x-ray diffraction of twoand three-dimensional PSII crystals (9-12). Recently, a 3.8-Å resolution structure of the oxygen-evolving PSII complex from Synechecoccus elongatus was determined (13).The PSII RC has six chlorophylls (Chls), two pheophytins (Pheos), two quinones, and one cytochrome b 559 (Cyt b 559 ) heme (8, 13). Significantly, the PSII RC has two additional Chls, relative to the BRC. Site-directed mutagenesis and spectroscopic studies demonstrated that the additional pair of Chls present in PSII is coordinated by a pair of conserved and C 2 symmetryrelated histidine residues (D1-H118 and D2-H117, Chlamydomonas reinhardtii nomenclature) (14-20). Unlike the four Chls and two Pheos involved in primary charge separation, the additional pair of Chls present in the PSII RC is located on the periphery of D1 and D2 polypeptides.Biophysical evidence for the involvement of the peripheral Chls in energy transfer first was obtained from analysis of P680 oxidation kinetics by Schelvis et al. (14). They observed a Ϸ30-ps P680 oxidation lifetime component, which they attributed to energy transfer from a Chl monomer to P680. Based on a Förster mechanism (21) for energy transfer, they calculated that the distance between the peripheral Chl and P680 was 30 Å, a distance confirmed by the recent PSII crystal structure. A similar distance relationship also was predicted on the basis of Chl fluorescence decay kine...

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Section: Resultsmentioning

confidence: 64%

Functional asymmetry of photosystem II D1 and D2 peripheral chlorophyll mutants of Chlamydomonas reinhardtii

Wang

Gosztola

Ruffle

et al. 2002

Proc. Natl. Acad. Sci. U.S.A.

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“…Membrane proteins were solubilized for separation by sucrose gradients, as described above or in Gall et al (1998), for separation in blue native PAGE (Schägger and von Jagow, 1991), or they were solubilized according to Allen and Staehelin (1991) for nondenaturing PAGE but in the absence of octylglucoside. A mixture of standard proteins was used for determining molecular masses in simultaneous separations: thyroglobulin; ferritin; catalase; lactate dehydrogenase; BSA (669, 440, 232, 140, and 67 kD, respectively) (584.4, 487, 389.6, 292, 194.8, and 97.4 kD).…”

Section: Molecular Mass Determination Of Membrane Protein Complexesmentioning

confidence: 99%

“…Here, the molecular masses of the complexes were assigned in parallel after separation in the native electrophoretic systems as 620, 450, 260, and 75 kD (open triangles). Fourth, reaction center complexes of photosystem II (PSII) containing D1, D2, cytochrome b 559 , and the psbI gene product were isolated essentially according to Nanba and Satoh (1987), with the modifications described in Gall et al (1998), and used as molecular mass markers in the determinations of newly assembled reaction center particles in the sucrose gradients. Error bars (x axis) correspond to the presence of identified thylakoid membrane complexes in the adjacent fraction of the sucrose gradients (0.5 arbitrary unit Ͻ 50% protein overlap Ͼ 1.0 arbitrary unit) (Figure 2A).…”

Section: Molecular Mass Determination Of Membrane Protein Complexesmentioning

confidence: 99%

Assembly of the D1 Precursor in Monomeric Photosystem II Reaction Center Precomplexes Precedes Chlorophyll a–Triggered Accumulation of Reaction Center II in Barley Etioplasts

Müller

Eichacker

1999

Plant Cell

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Assembly of plastid-encoded chlorophyll binding proteins of photosystem II (PSII) was studied in etiolated barley seedlings and isolated etioplasts and either the absence or presence of de novo chlorophyll synthesis. De novo assembly of reaction center complexes in etioplasts was characterized by immunological analysis of protein complexes solubilized from inner etioplast membranes and separated in sucrose density gradients. Previously characterized membrane protein complexes from chloroplasts were utilized as molecular mass standards for sucrose density gradient separation analysis. In etiolated seedlings, induction of chlorophyll a synthesis resulted in the accumulation of D1 in a dimeric PSII reaction center (RCII) complex. In isolated etioplasts, de novo chlorophyll a synthesis directed accumulation of D1 precursor in a monomeric RCII precomplex that also included D2 and cytochrome b 559 . Chlorophyll a synthesis that was chemically prolonged in darkness neither increased the yield of RCII monomers nor directed assembly of RCII dimers in etioplasts. We therefore conclude that in etioplasts, assembly of the D1 precursor in monomeric RCII precomplexes precedes chlorophyll a -triggered accumulation of reaction center monomers. INTRODUCTIONIn higher plants grown in darkness, formation of the photosynthetic apparatus is contingent on the light-dependent induction of chloroplast development. Light regulates synthesis of the chlorophyll a precursor protochlorophyllide a and is used as a substrate to enable the enzymatic re duction of protochlorophyllide a into chlorophyllide a by NADPH-protochlorophyllide oxidoreductase (POR) (von Wettstein et al., 1995;Fujita, 1996). The subsequent enzymatic esterification of chlorophyllide a to chlorophyll a has been found to be the decisive step for the accumulation of the chlorophyll a binding apoproteins P700A/P700B, CP47, CP43, and D1 of photosystems I and II (PSI and PSII), because binding of chlorophyll a to the apoproteins confers stability against proteolysis (Eichacker et al., 1996a). Similarly, other chlorophyll-associated proteins, including the nuclear-encoded chlorophyll a / b binding light-harvesting proteins (Bennett, 1981;Kuttkat et al., 1998), PSI chlorophyll proteins in Chlamydomonas (Herrin et al., 1992), and bacteriochlorophyll binding proteins of photosynthetic bacteria, are stabilized by chlorophyll (Dierstein, 1983). As shown indirectly by spectroscopy and by photochemical activity measurements, binding of chlorophyll a occurs within the first hour after illumination of etiolated barley (Egnéus et al., 1972;Wellburn and Hampp, 1979;Burkey, 1986;Ohashi et al., 1989;Franck, 1993); however, no direct evidence for chlorophyll a -dependent photosystem assembly has been reported.Chlorophyll a -dependent accumulation of plastidencoded chlorophyll a binding proteins is regulated at the cotranslational and post-translational levels (Klein and Mullet, 1986;van Wijk and Eichacker, 1996;Edhofer et al., 1998;Mühlbauer and Eichacker, 1998). During the first hour of illum...

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“…Exchange reactions with externally added pigments allow sitedirected exchanges of the Chl (BChl) and/or Pheo (BPheo) in bacterial RCs and PS II RCs. As shown in previous work (Gall et al 1998;Germano et al 2000;Zehetner et al 2002), it is possible to replace one of the six Chl in the PS II RC by incubation with several modified pigments, including [3-acetyl]-Chl, modified Pheo, and Zn-Chl.…”

Section: Introductionmentioning

confidence: 79%

“…Pigment replacements have been successful with bacterial RC and PS II RC (Scheer and Struck 1990;Gall et al 1998;Germano et al 2000;Zehetner et al 2002). Exchange reactions with externally added pigments allow sitedirected exchanges of the Chl (BChl) and/or Pheo (BPheo) in bacterial RCs and PS II RCs.…”

Section: Introductionmentioning

confidence: 99%

Pigment exchange of Photosystem II reaction center by chlorophyll d

et al. 2005

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Pigment exchanges among photosystem reaction centers (RCs) are useful for the identification and functional analysis of chromophores in photosynthetic organisms. Pigment replacement within the spinach Photosystem II RC was performed with Chl d derived from the oxygenic alga Acaryochloris marina, using a protocol similar to that reported previously [Gall et al. (1998) FEBS Lett 434: 88-92] based on the incubation of reaction centers with an excess of other pigments. In this study, we analyzed Chl d-modified monomeric RC which was separated from Chl d-modified dimeric RC by size-exclusion chromatography. Based on the assumption of a constant ratio of two Pheo a molecules per RC, the number of Chl a molecules in Chl d-modified monomeric RCs was found to decrease from six to four. The absorption spectrum of the Chl d-modified monomeric RC at room temperature showed a large peak at 699.5 nm originating from Chl d and a small peak at 672.5 nm orignating from Chl a. Photoaccumulation of the Pheo a- in Chl d-modified monomeric RC, in the presence of sodium dithionate and methyl viologen, did not differ significantly from that in control RC, showing that the Chl d-modified monomeric RC retains its charge separation activity and photochemically active Pheo a.

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Modification of pigment composition in the isolated reaction center of photosystem II

Cited by 19 publications

References 41 publications

Functional asymmetry of photosystem II D1 and D2 peripheral chlorophyll mutants of Chlamydomonas reinhardtii

Functional asymmetry of photosystem II D1 and D2 peripheral chlorophyll mutants of Chlamydomonas reinhardtii

Assembly of the D1 Precursor in Monomeric Photosystem II Reaction Center Precomplexes Precedes Chlorophyll a–Triggered Accumulation of Reaction Center II in Barley Etioplasts

Pigment exchange of Photosystem II reaction center by chlorophyll d

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