Isolation and characterization of the 47 kDa protein and the Dl–D2-cytochrome b-559 complex

Ghanotakis, Demetrios F.; Paula, Julio C. de; Demetriou, D. M.; Bowlby, Neil R.; Petersen, J.; Babcock, Gerald T.; Yocum, Charles F.

doi:10.1016/s0005-2728(89)80164-1

Cited by 132 publications

(82 citation statements)

References 20 publications

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“…2, lane 11). The results indicate that the purified PSII complexes consist of CP47, CP43Ј, D1, D2, cyt b 559 , PsbI, and one additional small polypeptide and are thus comparable to purified complexes obtained from spinach (13,14) and Synechocystis (Fig. 2, lane 7).…”

Section: Resultssupporting

confidence: 67%

Identification of the special pair of photosystem II in a chlorophyll d -dominated cyanobacterium

Tomo

Okubo

Akimoto

et al. 2007

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

125

127

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The composition of photosystem II (PSII) in the chlorophyll (Chl) d-dominated cyanobacterium Acaryochloris marina MBIC 11017 was investigated to enhance the general understanding of the energetics of the PSII reaction center. We first purified photochemically active complexes consisting of a 47-kDa Chl protein (CP47), CP43 (PcbC), D1, D2, cytochrome b 559, PsbI, and a small polypeptide. The pigment composition per two pheophytin (Phe) a molecules was 55 ؎ 7 Chl d, 3.0 ؎ 0.4 Chl a, 17 ؎ 3 ␣-carotene, and 1.4 ؎ 0.2 plastoquinone-9. The special pair was detected by a reversible absorption change at 713 nm (P713) together with a cation radical band at 842 nm. FTIR difference spectra of the specific bands of a 3-formyl group allowed assignment of the special pair. The combined results indicate that the special pair comprises a Chl d homodimer. The primary electron acceptor was shown by photoaccumulation to be Phe a, and its potential was shifted to a higher value than that in the Chl a/Phe a system. The overall energetics of PSII in the Chl d system are adjusted to changes in the redox potentials, with P713 as the special pair using a lower light energy at 713 nm. Taking into account the reported downward shift in the potential of the special pair of photosystem I (P740) in A. marina, our findings lend support to the idea that changes in photosynthetic pigments combine with a modification of the redox potentials of electron transfer components to give rise to an energetic adjustment of the total reaction system. Acaryochloris marina ͉ FTIR ͉ reaction center ͉ photosynthesis ͉ electron transfer C hlorophyll (Chl) a has a ubiquitous role as an electron donor in the photochemical reactions of oxygenic photosynthesis, in which two kinds of photosystem, namely photosystem I (PSI) and photosystem II (PSII), cooperatively drive photosynthetic electron flow from water to NADP ϩ . The reduced cofactor, NADPH, is then used for CO 2 fixation. Chl a is a key pigment that serves as an electron donor called the special pair in PSI and PSII. Acaryochloris spp. are unique cyanobacteria that differ from the majority of photosynthetic organisms by having Chl d (3-desvinyl-3-formyl Chl a) (1-4) as the major pigment (Ͼ95%); Chl a is a minor component but is never absent (5, 6). In photosynthetic organisms, changes in pigment composition affect both the function of pigments and their reaction environments, including the modified proteins that accommodate them. Photosynthetic pigments function in two roles: as lightharvesting components and as electron transfer components. Light harvesting is mainly governed by the orientation and energy levels of pigments, and, in this context, a particular excitation energy level is not an absolute precondition for function, but a relative one. On the other hand, electron transfer reactions are governed by an absolute redox potential, because the photosynthetic oxidation of water requires a very high potential, whereas reduction of NADP ϩ requires a very low potential. For this reason, it is of particul...

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Section: Resultssupporting

confidence: 67%

Identification of the special pair of photosystem II in a chlorophyll d -dominated cyanobacterium

Tomo

Okubo

Akimoto

et al. 2007

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

125

127

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“…We found that the isolated aggregates are very stable, and that incubation with 0.5% -DM and 2 M LiClO 4 did not induce the release of monomeric IsiA. The same treatment effectively removed the sequence-related CP43 protein from the PSII core complex (39). Figure 2 shows the room-temperature absorption spectrum of the isolated aggregates.…”

Section: Pigment Composition and Structure Of Isolated Isiamentioning

confidence: 88%

Aggregates of the Chlorophyll-Binding Protein IsiA (CP43‘) Dissipate Energy in Cyanobacteria

et al. 2005

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“…A reaction center of PSII consisting of the Dl and D2 proteins, the a and 13 subunits of cytochrome b559 (Cyt b559), and the product of the psbI gene was first isolated by Nanba and Satoh (1). Since then similar preparations have been isolated by a number of workers using different materials and slightly different procedures (2)(3)(4)(5)(6). Although most of the procedures used involved solubilization with Triton X-100, it has emerged that n-dodecyl f3-D-maltoside (DM) was helpful for subsequent stabilization of the isolated complex (5,7).…”

mentioning

confidence: 99%

Photochemistry and spectroscopy of a five-chlorophyll reaction center of photosystem II isolated by using a Cu affinity column.

Vacha

Joseph

Durrant

et al. 1995

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

103

128

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A reaction center of photosystem II was isolated from Pisum sativum by using immobilized metal affinity chromatography. This reaction center is photochemically active and has a room temperature Qy chlorophyll (Chl) absorption band peaking at 677.5 nm. From HPLC analysis, the pigment stoichiometry was suggested to be 5 Chls per 1 (3-carotene per 2 pheophytins. Low-temperature absorption measurements at 77 K were consistent with the removal of one of the Chls associated with the usual form of the reaction center isolated by using ion-exchange chromatography. Transient absorption spectroscopy on the picosecond time scale indicated that the Chl removed belongs to a pool of Chl absorbing at -670 nm (C6701I) that transfers energy relatively slowly to the primary donor P680 in support of our recently proposed model. The results also support the previous conclusion that radical pair formation is largely associated with a 21-ps time constant when P680 is directly excited and that the identity of C6701 is likely to be peripherally bound ChIs possibly ligated to conserved His residues at positions 118 on the Dl and D2 proteins.that have been assigned to energy transfer from accessory Phs and Chls to the primary donor P680 (17,(19)(20)(21)(22)(23)(24). It has been further suggested that the slow energy transfer processes are associated with two additional Chls bound to the periphery of the reaction center complex (21, 24). Moreover, the presence of these slow energy transfer processes has made the determination of the time constants for primary charge separation more difficult, leading to controversy (16,21,(24)(25)(26)(27)(28). It is therefore particularly interesting to compare the primary photochemistry of the 6-Chl-containing PSII reaction center with those in which 1 or 2 of the peripheral Chl molecules have been removed. In this paper, we report a procedure for isolating the reaction center of PSII by using immobilized metal affinity chromatography. HPLC analysis indicated that the complex contained 5 Chls per 2 Phs and, relative to that of the 6-Chl-containing preparation, showed a spectral shift indicative of the removal of an accessory Chl absorbing on the blue side of the main Qy band. The role of this Chl as an accessory pigment was confirmed by time-resolved picosecond absorption spectroscopy.

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Isolation and characterization of the 47 kDa protein and the Dl–D2-cytochrome b-559 complex

Cited by 132 publications

References 20 publications

Identification of the special pair of photosystem II in a chlorophyll d -dominated cyanobacterium

Identification of the special pair of photosystem II in a chlorophyll d -dominated cyanobacterium

Aggregates of the Chlorophyll-Binding Protein IsiA (CP43‘) Dissipate Energy in Cyanobacteria

Photochemistry and spectroscopy of a five-chlorophyll reaction center of photosystem II isolated by using a Cu affinity column.

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