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Govindjee G, Amesz B, Garab G, Stirbet A. Remembering Jan Amesz (1934-2001): a great gentleman, a major discoverer, and an internationally renowned biophysicist of both oxygenic and anoxygenic photosynthesis a. PHOTOSYNTHESIS RESEARCH 2024; 160:125-142. [PMID: 38687462 DOI: 10.1007/s11120-024-01102-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Accepted: 04/18/2024] [Indexed: 05/02/2024]
Abstract
We present here the research contributions of Jan Amesz (1934-2001) on deciphering the details of the early physico-chemical steps in oxygenic photosynthesis in plants, algae and cyanobacteria, as well as in anoxygenic photosynthesis in purple, green, and heliobacteria. His research included light absorption and the mechanism of excitation energy transfer, primary photochemistry, and electron transfer steps until the reduction of pyridine nucleotides. Among his many discoveries, we emphasize his 1961 proof, with L. N. M. Duysens, of the "series scheme" of oxygenic photosynthesis, through antagonistic effects of Light I and II on the redox state of cytochrome f. Further, we highlight the following research on oxygenic photosynthesis: the experimental direct proof that plastoquinone and plastocyanin function at their respective places in the Z-scheme. In addition, Amesz's major contributions were in unraveling the mechanism of excitation energy transfer and electron transport steps in anoxygenic photosynthetic bacteria (purple, green and heliobacteria). Before we present his research, focusing on his key discoveries, we provide a glimpse of his personal life. We end this Tribute with reminiscences from three of his former doctoral students (Sigi Neerken; Hjalmar Pernentier, and Frank Kleinherenbrink) and from several scientists (Suleyman Allakhverdiev; Robert Blankenship; Richard Cogdell) including two of the authors (G. Garab and A. Stirbet) of this Tribute.
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Affiliation(s)
- Govindjee Govindjee
- Department of Plant Biology, Department of Biochemistry, and the Center of Biophysics & Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
| | - Bas Amesz
- Albertus Perkstraat 35, 1217 NL, Hilversum, The Netherlands
| | - Győző Garab
- Biological Research Centre, Institute of Plant Biology, HUN-REN, 6726, Szeged, Hungary
- Department of Physics, Faculty of Science, University of Ostrava, 71000, Ostrava, Czech Republic
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Zabelin AA, Khristin AM, Kovalev VB, Khatypov RA, Shkuropatov AY. Primary charge separation in native and plant pheophytin a-modified reaction centers of Chloroflexus aurantiacus: Ultrafast transient absorption measurements at low temperature. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2023; 1864:148976. [PMID: 37061174 DOI: 10.1016/j.bbabio.2023.148976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/31/2023] [Accepted: 04/06/2023] [Indexed: 04/17/2023]
Abstract
Ultrafast transient absorption (TA) spectroscopy was used to study electron transfer (ET) at 100 K in native (as isolated) reaction centers (RCs) of the green filamentous photosynthetic bacterium Chloroflexus (Cfl.) aurantiacus. The rise and decay of the 1028 nm anion absorption band of the monomeric bacteriochlorophyll a molecule at the BA binding site were monitored as indicators of the formation and decay of the P+BA- state, respectively (P is the primary electron donor, a dimer of bacteriochlorophyll a molecules). Global analysis of the TA data indicated the presence of at least two populations of the P⁎ excited state, which decay by distinct means, forming the state P+HA- (HA is a photochemically active bacteriopheophytin a molecule). In one population (~65 %), P⁎ decays in ~2 ps with the formation of P+HA- via a short-lived P+BA- intermediate in a two-step ET process P⁎ → P+BA- → P+HA-. In another population (~35 %), P⁎ decays in ~20 ps to form P+HA- via a superexchange mechanism without producing measurable amounts of P+BA-. Similar TA measurements performed on chemically modified RCs of Cfl. aurantiacus containing plant pheophytin a at the HA binding site also showed the presence of two P⁎ populations (~2 and ~20 ps), with P⁎ decaying through P+BA- only in the ~2 ps population. At 100 K, the quantum yield of primary charge separation in native RCs is determined to be close to unity. The results are discussed in terms of involving a one-step P⁎ → P+HA- superexchange process as an alternative highly efficient ET pathway in Cfl. aurantiacus RCs.
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Affiliation(s)
- Alexey A Zabelin
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", 142290 Pushchino, Moscow Region, Russian Federation
| | - Anton M Khristin
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", 142290 Pushchino, Moscow Region, Russian Federation
| | - Vyacheslav B Kovalev
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", 142290 Pushchino, Moscow Region, Russian Federation
| | - Ravil A Khatypov
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", 142290 Pushchino, Moscow Region, Russian Federation
| | - Anatoly Yu Shkuropatov
- Institute of Basic Biological Problems of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", 142290 Pushchino, Moscow Region, Russian Federation.
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Zabelin AA, Shkuropatov AY. Pigment-modified reaction centers of Chloroflexus aurantiacus: chemical exchange of bacteriopheophytins with plant-type pheophytins. PHOTOSYNTHESIS RESEARCH 2021; 149:313-328. [PMID: 34138452 DOI: 10.1007/s11120-021-00855-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/06/2021] [Indexed: 06/12/2023]
Abstract
The pigment composition of isolated reaction centers (RCs) of the green filamentous bacterium Chloroflexus (Cfl.) aurantiacus was changed by chemical exchange of native bacteriopheophytin a (BPheo) molecules with externally added pheophytin a (Pheo) or [3-acetyl]-Pheo upon incubation of RC/pheophytin mixtures at room temperature and 45 °C. The modified RCs were characterized by Vis/NIR absorption spectroscopy, and the effect of pigment exchange on RC photochemical activity was assessed by measuring the photoaccumulation of the reduced pigment at the binding site HA. It is shown that both pheophytins can be exchanged into the HA site instead of BPheo by incubation at room temperature. While the newly introduced Pheo molecule is not active in electron transfer, the [3-acetyl]-Pheo molecule is able to replace functionally the photoreducible HA BPheo molecule with the formation of the [3-acetyl]-Pheo- radical anion instead of the BPheo-. After incubation at 45 °C, the majority (~ 90%) of HA BPheo molecules is replaced by both Pheo and [3-acetyl]-Pheo. Only a partial replacement of inactive BPheo molecules with pheophytins is observed even when the incubation temperature is raised to 50 °C. The results are discussed in terms of (i) differences in the accessibility of BPheo binding sites for extraneous pigments depending on structural constraints and incubation temperature and (ii) the effect of the reduction potential of pigments introduced into the HA site on the energetics of the charge separation process. The possible implication of Pheo-exchanged preparations for studying early electron-transfer events in Cfl. aurantiacus RCs is considered.
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Affiliation(s)
- Alexey A Zabelin
- Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Institute of Basic Biological Problems of the Russian Academy of Sciences, 142290, Pushchino, Moscow Region, Russian Federation
| | - Anatoly Ya Shkuropatov
- Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Institute of Basic Biological Problems of the Russian Academy of Sciences, 142290, Pushchino, Moscow Region, Russian Federation.
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Yakovlev AG, Khmelnitsky AY, Shuvalov VA. Femtosecond charge separation in dry films of reaction centers of Rhodobacter sphaeroides and Chloroflexus aurantiacus. BIOCHEMISTRY (MOSCOW) 2012; 77:444-55. [DOI: 10.1134/s0006297912050045] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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YAKOVLEV ANDREIG, SHKUROPATOVA TATIANAA, VASILIEVA LYUDMILAG, YA. SHKUROPATOV ANATOLI, SHUVALOV VLADIMIRA. WAVE PACKET MOTIONS COUPLED TO ELECTRON TRANSFER IN REACTION CENTERS OF CHLOROFLEXUS AURANTIACUS. J Bioinform Comput Biol 2012; 6:643-66. [DOI: 10.1142/s0219720008003680] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2007] [Revised: 12/03/2007] [Accepted: 01/04/2008] [Indexed: 11/18/2022]
Abstract
Transient absorption difference spectroscopy with ~20 femtosecond (fs) resolution was applied to study the time and spectral evolution of low-temperature (90 K) absorbance changes in isolated reaction centers (RCs) of Chloroflexus (C.) aurantiacus. In RCs, the composition of the B-branch chromophores is different with respect to that of purple bacterial RCs by occupying the BB binding site of accessory bacteriochlorophyll by bacteriopheophytin molecule (ΦB). It was found that the nuclear wave packet motion induced on the potential energy surface of the excited state of the primary electron donor P* by ~20 fs excitation leads to a coherent formation of the states [Formula: see text] and [Formula: see text] (BA is a bacteriochlorophyll monomer in the A-branch of cofactors). The processes were studied by measuring coherent oscillations in kinetics of the absorbance changes at 900 nm and 940 nm (P* stimulated emission), at 750 nm and 785 nm (ΦB absorption bands), and at 1,020–1028 nm ([Formula: see text] absorption band). In RCs, the immediate bleaching of the P band at 880 nm and the appearance of the stimulated wave packet emission at 900 nm were accompanied (with a small delay of 10–20 fs) by electron transfer from P* to the B-branch with bleaching of the ΦB absorption band at 785 nm due to [Formula: see text] formation. These data are consistent with recent measurements for the mutant HM182L Rb. sphaeroides RCs (Yakovlev et al., Biochim Biophys Acta1757:369–379, 2006). Only at a delay of 120 fs was the electron transfer from P* to the A-branch observed with a development of the [Formula: see text] absorption band at 1028 nm. This development was in phase with the appearance of the P* stimulated emission at 940 nm. The data on the A-branch electron transfer in C. aurantiacus RCs are consistent with those observed in native RCs of Rb. sphaeroides. The mechanism of charge separation in RCs with the modified B-branch pigment composition is discussed in terms of coupling between the nuclear wave packet motion and electron transfer from P* to ΦB and BA primary acceptors in the B-branch and A-branch, respectively.
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Affiliation(s)
- ANDREI G. YAKOVLEV
- Department of Photobiophysics, Belozersky Institute of Chemical and Physical Biology, Moscow State University, Moscow 119991, Russian Federation
| | - TATIANA A. SHKUROPATOVA
- Department of Biophysics, Huygens Laboratory, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands
| | - LYUDMILA G. VASILIEVA
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russian Federation
| | - ANATOLI YA. SHKUROPATOV
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russian Federation
| | - VLADIMIR A. SHUVALOV
- Department of Photobiophysics, Belozersky Institute of Chemical and Physical Biology, Moscow State University, Moscow 119991, Russian Federation
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russian Federation
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Zabelin AA, Shkuropatova VA, Shuvalov VA, Shkuropatov AY. FTIR spectroscopy of the reaction center of Chloroflexus aurantiacus: Photoreduction of the bacteriopheophytin electron acceptor. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1807:1013-21. [DOI: 10.1016/j.bbabio.2011.05.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Revised: 05/18/2011] [Accepted: 05/19/2011] [Indexed: 11/25/2022]
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Collins AM, Kirmaier C, Holten D, Blankenship RE. Kinetics and energetics of electron transfer in reaction centers of the photosynthetic bacterium Roseiflexus castenholzii. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1807:262-9. [PMID: 21126505 DOI: 10.1016/j.bbabio.2010.11.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 11/18/2010] [Accepted: 11/19/2010] [Indexed: 10/18/2022]
Abstract
The kinetics and thermodynamics of the photochemical reactions of the purified reaction center (RC)-cytochrome (Cyt) complex from the chlorosome-lacking, filamentous anoxygenic phototroph, Roseiflexus castenholzii are presented. The RC consists of L- and M-polypeptides containing three bacteriochlorophyll (BChl), three bacteriopheophytin (BPh) and two quinones (Q(A) and Q(B)), and the Cyt is a tetraheme subunit. Two of the BChls form a dimer P that is the primary electron donor. At 285K, the lifetimes of the excited singlet state, P*, and the charge-separated state P(+)H(A)(-) (where H(A) is the photoactive BPh) were found to be 3.2±0.3 ps and 200±20 ps, respectively. Overall charge separation P*→→ P(+)Q(A)(-) occurred with ≥90% yield at 285K. At 77K, the P* lifetime was somewhat shorter and the P(+)H(A)(-) lifetime was essentially unchanged. Poteniometric titrations gave a P(865)/P(865)(+) midpoint potential of +390mV vs. SHE. For the tetraheme Cyt two distinct midpoint potentials of +85 and +265mV were measured, likely reflecting a pair of low-potential hemes and a pair of high-potential hemes, respectively. The time course of electron transfer from reduced Cyt to P(+) suggests an arrangement where the highest potential heme is not located immediately adjacent to P. Comparisons of these and other properties of isolated Roseiflexus castenholzii RCs to those from its close relative Chloroflexus aurantiacus and to RCs from the purple bacteria are made.
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Affiliation(s)
- Aaron M Collins
- Department of Chemistry, Washington University in St. Louis, St. Louis, MO 63130, USA
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Yakovlev AG, Shkuropatova TA, Vasilieva LG, Shkuropatov AY, Shuvalov VA. Femtosecond phase of charge separation in reaction centers of Chloroflexus aurantiacus. BIOCHEMISTRY. BIOKHIMIIA 2009; 74:846-854. [PMID: 19817684 DOI: 10.1134/s0006297909080057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Difference absorption spectroscopy with temporal resolution of approximately 20 fsec was used to study the primary phase of charge separation in isolated reaction centers (RCs) of Chloroflexus aurantiacus at 90 K. An ensemble of difference (light-minus-dark) absorption spectra in the 730-795 nm region measured at -0.1 to 4 psec delays relative to the excitation pulse was analyzed. Comparison with analogous data for RCs of HM182L mutant of Rhodobacter sphaeroides having the same pigment composition identified the 785 nm absorption band as the band of bacteriopheophytin Phi(B) in the B-branch. By study the bleaching of this absorption band due to formation of Phi(B)(-), it was found that a coherent electron transfer from P* to the B-branch occurs with a very small delay of 10-20 fsec after excitation of dimer bacteriochlorophyll P. Only at 120 fsec delay electron transfer from P* to the A-branch occurs with the formation of bacteriochlorophyll anion B(A)(-) absorption band at 1028 nm and the appearance of P* stimulated emission at 940 nm, as also occurs in native RCs of Rb. sphaeroides. It is concluded that a nuclear wave packet motion on the potential energy surface of P* after a 20-fsec light pulse excitation leads to the coherent formation of the P(+)Phi(B)(-) and P(+)B(A)(-) states.
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Affiliation(s)
- A G Yakovlev
- Department of Photobiophysics, Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, 119991, Russia.
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Schweitzer G, Hucke M, Griebenow K, Müller MG, Holzwarth AR. Charge separation kinetics in isolated photosynthetic reaction centers of Chloroflexus aurantiacus (with QA reduced) at low temperatures. Chem Phys Lett 1992. [DOI: 10.1016/0009-2614(92)86119-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Kleinherenbrink FA, Deinum G, Otte SC, Hoff AJ, Amesz J. Energy transfer from long-wavelength absorbing antenna bacteriochlorophylls to the reaction center. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1992. [DOI: 10.1016/0005-2728(92)90216-o] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Temperature dependence of the initial electron-transfer kinetics in photosynthetic reaction centers of Chloroflexus aurantiacus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1991. [DOI: 10.1016/s0005-2728(05)80141-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Shiozawa JA, Lottspeich F, Feick R. The photochemical reaction center of Chloroflexus aurantiacus is composed of two structurally similar polypeptides. EUROPEAN JOURNAL OF BIOCHEMISTRY 1987; 167:595-600. [PMID: 3308462 DOI: 10.1111/j.1432-1033.1987.tb13377.x] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A method has been devised which allowed the isolation of highly purified reaction center from the thermophilic green bacterium, Chloroflexus aurantiacus. The procedure consisted of three chromatography steps. The final step was fast protein liquid chromatography on Mono Q in the presence of nonanoyl-N-methylglucamide (Mega-9). The purified reaction center complex was photochemically active and had an A280/A813 of 1.4 or less. Under non-denaturing conditions, a pigmented protein band having a Mr of 52,000-55,000 was observed in sodium dodecyl sulfate gels. When the isolated complex was heat-dissociated in the presence of sodium dodecyl sulfate, just two polypeptides having very similar Mr (24,000 and 24,500) were observed. Two protein bands were also observed in two-dimensional isoelectric focusing/sodium-dodecyl-sulfate polyacrylamide gel electrophoresis; the PI values of the two polypeptides were 6.5 and 6.7. Partial peptide mapping of the two isolated subunits, using both enzymatic and chemical cleavage techniques, yielded almost identical patterns which indicated a high degree of sequence homology between the two polypeptides. The N-terminal amino acid sequences of the two polypeptides were identical and did not exhibit any homology to reaction center subunits of purple sulfur bacteria. The Chloroflexus reaction center is believed to be composed of one molecule of each polypeptide, the photoactive bacteriochlorophyll a dimer and, as accessory pigments, an additional bacteriochlorophyll a and three bacteriopheophytins. Hence, it appears to be the smallest photochemically active reaction center isolated to date.
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Affiliation(s)
- J A Shiozawa
- Max-Planck-Institut für Biochemie, Martinsried, Federal Republic of Germany
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Kirmaier C, Holten D. Primary photochemistry of reaction centers from the photosynthetic purple bacteria. PHOTOSYNTHESIS RESEARCH 1987; 13:225-260. [PMID: 24435821 DOI: 10.1007/bf00029401] [Citation(s) in RCA: 264] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/1987] [Accepted: 04/20/1987] [Indexed: 06/03/2023]
Abstract
Photosynthetic organisms transform the energy of sunlight into chemical potential in a specialized membrane-bound pigment-protein complex called the reaction center. Following light activation, the reaction center produces a charge-separated state consisting of an oxidized electron donor molecule and a reduced electron acceptor molecule. This primary photochemical process, which occurs via a series of rapid electron transfer steps, is complete within a nanosecond of photon absorption. Recent structural data on reaction centers of photosynthetic bacteria, combined with results from a large variety of photochemical measurements have expanded our understanding of how efficient charge separation occurs in the reaction center, and have changed many of the outstanding questions.
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Affiliation(s)
- C Kirmaier
- Department of Chemistry, Washington University, 63130, St. Louis, MO, USA
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Vasmel H, Amesz J, Hoff AJ. Analysis by exciton theory of the optical properties of the Chloroflexus aurantiacus reaction center. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90219-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Picosecond spectroscopy of the charge separation in reaction centers of Chloroflexus aurantiacus with selective excitation of the primary electron donor. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90072-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Kirmaier C, Blankenship RE, Holten D. Formation and decay of radical-pair state P+I− in Chloroflexus aurantiacus reaction centers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90182-9] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Photoreactions of bacteriopheophytins and bacteriochlorophylls in reaction centers of Rhodopseudomonas sphaeroides and Chloroflexus aurantiacus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90145-3] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Vasmel H, Van Dorssen RJ, De Vos GJ, Amesz J. Pigment organization and energy transfer in the green photosynthetic bacterium Chloroflexus aurantiacus : I. The cytoplasmic membrane. PHOTOSYNTHESIS RESEARCH 1986; 7:281-294. [PMID: 24443124 DOI: 10.1007/bf00014681] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/1985] [Revised: 08/22/1985] [Indexed: 06/03/2023]
Abstract
We have studied the pigment arrangement in purified cytoplasmic membranes of the thermophilic green bacterium Chloroflexus aurantiacus. The membranes contain 30-35 antenna bacteriochlorophyll a molecules per reaction center; these are organized in the B808-866 light-harvesting complex, together with carotenoids in a 2:1 molar ratio. Measurements of linear dichroism in a pressed polyacrylamide gel permitted the accurate determination of the orientation of the optical transition dipole moments with respect to the membrane plane. Combination of linear dichroism and low temperature fluorescence polarization data shows that the Qy transitions of the BChl 866 molecules all lie almost perfectly parallel to the membrane plane, but have no preferred orientation within the plane. The BChl 808 Qy transitions make an average angle of about 44° with this plane. This demonstrates that there are clear structural differences between the B808-866 complex of C. aurantiacus and the B800-850 complex of purple bacteria. Excitation energy transfer from carotenoid to BChl a proceeds with about 40% efficiency, while the efficiency of energy transfer from BChl 808 to BChl 866 approaches 100%. From the minimal energy transfer rate between the two spectral forms of BChl a, obtained by analysis of low temperature fluorescence emission spectra, a maximal distance between BChl 808 and BChl 866 of 23 Å was derived.
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Affiliation(s)
- H Vasmel
- Department of Biophysics, Huygens Laboratory of the State University, P.O. Box 9504, 2300 RA, Leiden, The Netherlands
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Amesz J, Duysens LN. Electron donors and acceptors in photosynthetic reaction centers. PHOTOSYNTHESIS RESEARCH 1986; 10:337-346. [PMID: 24435381 DOI: 10.1007/bf00118299] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A review is given of primary and associated electron transport reactions in various division of photosynthetic bacteria and in the two photosystems of plant photosynthesis. Two types of electron acceptor chains are distinguished: type 'Q', found in purple bacteria, Chloroflexus and system II of oxygenic photosynthesis and type 'F', found in green sulfur bacteria, Heliobacterium and photosystem I. Secondary donor reactions are discussed in relation to plant photosystem II.
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Affiliation(s)
- J Amesz
- Department of Biophysics, Huygens Laboratory of the State University, P.O. Box 9504, 2300 RA, Leiden, The Netherlands
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Optical and structural properties of chlorosomes of the photosynthetic green sulfur bacterium Chlorobium limicola. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90162-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Blankenship RE. Electron transport in green photosynthetic bacteria. PHOTOSYNTHESIS RESEARCH 1985; 6:317-333. [PMID: 24442952 DOI: 10.1007/bf00054106] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/1984] [Accepted: 11/27/1984] [Indexed: 06/03/2023]
Abstract
Green bacteria make up two of the four families of anoxygenic photosynthetic prokaryotes. The two families have similar pigment compositions and membrane fine structure, and both contain a specialized antenna structure known as a chlorosome. The primary photochemistry and electron transport pathways of the two groups are, however, quite distinct. The anaerobic green bacteria (Chlorobiaceae) contain low-potential iron-sulfur proteins as early electron acceptors and can directly reduce NAD(+) in a manner reminiscent of Photosystem I of oxygenic organisms. The facultatively aerobic green bacteria (Chloroflexaceae) contain quinone-type acceptors and have an overall pattern of electron transport very similar to that found in purple bacteria. Many aspects of energy storage in green bacteria, especially photophosphorylation and the role of cytochrome b/c complexes in electron transport, remain poorly understood.
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Affiliation(s)
- R E Blankenship
- Department of Chemistry, Amherst, Amherst College, 01002, Amherst, MA, USA
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Siefermann-Harms D. Carotenoids in photosynthesis. I. Location in photosynthetic membranes and light-harvesting function. ACTA ACUST UNITED AC 1985. [DOI: 10.1016/0304-4173(85)90006-0] [Citation(s) in RCA: 228] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
26
|
van Dorssen R, Vasmel H, Amesz J. Antenna organization and energy transfer in membranes of Heliobacterium chlorum. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1985. [DOI: 10.1016/0005-2728(85)90063-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Structure of Chloroflexus aurantiacus reaction center: Photoselection at low temperature. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1985. [DOI: 10.1016/0005-2728(85)90176-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
28
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|
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Kramer HJ, Pennoyer JD, Van Grondelle R, Westerhuis WH, Niederman RA, Amesz J. Low-temperature optical properties and pigment organization of the B875 light-harvesting bacteriochlorophyll-protein complex of purple photosynthetic bacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1984. [DOI: 10.1016/0005-2728(84)90204-4] [Citation(s) in RCA: 104] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
30
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Kirmaier C, Holten D, Mancino L, Blankenship RE. Picosecond photodichroism studies on reaction centers from the green photosynthetic bacterium Chloroflexus aurantiacus. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1984. [DOI: 10.1016/0005-2728(84)90007-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Kramer HJ, van Grondelle R, Hunter C, Westerhuis WH, Amesz J. Pigment organization of the B800–850 antenna complex of Rhodopseudomonas sphaeroides. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1984. [DOI: 10.1016/0005-2728(84)90009-4] [Citation(s) in RCA: 168] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Vasmel H, Swarthoff T, Kramer HJ, Amesz J. Isolation and properties of a pigment-protein complex associated with the reaction center of the green photosynthetic sulfur bacterium Prosthecochloris aestuarii. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1983. [DOI: 10.1016/0005-2728(83)90210-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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