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Unusual features of the c-ring of F 1F O ATP synthases. Sci Rep 2019; 9:18547. [PMID: 31811229 PMCID: PMC6897951 DOI: 10.1038/s41598-019-55092-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 11/19/2019] [Indexed: 11/23/2022] Open
Abstract
Membrane integral ATP synthases produce adenosine triphosphate, the universal “energy currency” of most organisms. However, important details of proton driven energy conversion are still unknown. We present the first high-resolution structure (2.3 Å) of the in meso crystallized c-ring of 14 subunits from spinach chloroplasts. The structure reveals molecular mechanisms of intersubunit contacts in the c14-ring, and it shows additional electron densities inside the c-ring which form circles parallel to the membrane plane. Similar densities were found in all known high-resolution structures of c-rings of F1FO ATP synthases from archaea and bacteria to eukaryotes. The densities might originate from isoprenoid quinones (such as coenzyme Q in mitochondria and plastoquinone in chloroplasts) that is consistent with differential UV-Vis spectroscopy of the c-ring samples, unusually large distance between polar/apolar interfaces inside the c-ring and universality among different species. Although additional experiments are required to verify this hypothesis, coenzyme Q and its analogues known as electron carriers of bioenergetic chains may be universal cofactors of ATP synthases, stabilizing c-ring and prevent ion leakage through it.
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Knox PP, Lukashev EP, Gorokhov VV, Seifullina NK, Paschenko VZ. Relaxation processes accompanying electron stabilization in the quinone acceptor part of Rb. sphaeroides reaction centers. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2018; 189:145-151. [PMID: 30347352 DOI: 10.1016/j.jphotobiol.2018.10.005] [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: 07/23/2018] [Revised: 10/03/2018] [Accepted: 10/04/2018] [Indexed: 06/08/2023]
Abstract
The temperature dependence of the dark recombination rate in photooxidized bacteriochlorophyll (P) and photoreduced quinone acceptors (ubiquinones) QA and QB of photosynthetic reaction centers of purple bacteria Rhodobacter sphaeroides (Rb. sphaeroides) was studied. Photoinduced changes in the absorption were detected in the Qx absorption band of photooxidized bacteriochlorophyll at 600 nm and in the bands corresponding to the redox changes of ubiquinones at 335 and 420-450 nm. Kinetic analysis was used to evaluate the activation energy and the characteristic time of the transient process of relaxation accompanying electron stabilization at the final quinone acceptor. A comparative study of the kinetics of oxidation-reduction reactions of photoactive bacteriochlorophyll RC purple bacteria and quinone acceptors in their individual absorption bands is an informative approach to studying the mechanisms of this stabilization. The analysis of the revealed kinetic differences makes it possible to estimate the activation energy and the characteristic times of the transition relaxation processes associated with the stabilization of the electron in the quinone acceptor part of RC. Purple bacterial reaction centers have fundamental similarities with PSII reaction centers. Such a similarity represents evolutional closeness between the two types of RC. So it is possible that the photoinduced charge separation in PSII RC, as well as in purple bacteria RC, is also accompanied by definite conformational changes. The possible role of hydrogen bonds of surrounding protein in the relaxation processes accompanying the electron transfer to quinone acceptors is discussed.
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Affiliation(s)
- P P Knox
- Department of Biophysics, Biological Faculty of the M.V., Lomonosov Moscow State University, 119991 Moscow, Russia
| | - E P Lukashev
- Department of Biophysics, Biological Faculty of the M.V., Lomonosov Moscow State University, 119991 Moscow, Russia
| | - V V Gorokhov
- Department of Biophysics, Biological Faculty of the M.V., Lomonosov Moscow State University, 119991 Moscow, Russia
| | - N Kh Seifullina
- Department of Biophysics, Biological Faculty of the M.V., Lomonosov Moscow State University, 119991 Moscow, Russia
| | - V Z Paschenko
- Department of Biophysics, Biological Faculty of the M.V., Lomonosov Moscow State University, 119991 Moscow, Russia.
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Sun C. Removal of the H subunit results in enhanced exposure of the semiquinone sites in the LM dimer from Rhodobacter sphaeroides to oxidation by ferricyanide and by O 2. PHOTOSYNTHESIS RESEARCH 2017; 133:371-377. [PMID: 28540587 DOI: 10.1007/s11120-017-0404-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 05/17/2017] [Indexed: 06/07/2023]
Abstract
Bacterial reaction centers (RC) from Rhodobacter sphaeroides have been widely used to functionalize electrodes and to generate photocurrent. However, in most studies, direct electron transfer from the semiquinone to the electrode was not observed because the H subunit of the RC shields the semiquinone. It is demonstrated in the current work that removal of the H subunit effectively exposes the semiquinone sites in the LM dimer. This is demonstrated by measuring the second-order rate constant for the reaction between ferricyanide and the anionic semiquinone Q A- formed by an actinic flash. The rate constant increases 1000-fold for Q A- oxidation by ferricyanide in the LM dimer compared to the intact RC. The second-order rate constant approaches the diffusion limit of 6 × 109 M-1·s-1 at low pH, but it decreases steadily when the pH is above 6.5. This pH dependence suggests that the protonation state of the LM dimer plays an important role in controlling the electron transfer kinetics. It is also shown that the addition of exogenous ubiquinone to replenish the QB site, which is mostly empty in the LM dimer, leads to oxidation of Q A- by O2 following an actinic flash. It is concluded that removal of the H subunit results in exposure of the semiquinone sites of the LM dimer to externally added oxidants and may provide a strategy for enhancing direct electron transfer from the RC to an electrode.
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Affiliation(s)
- Chang Sun
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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Knox PP, Krasilnikov PM, Lukashev EP, Seifullina NK, Rubin AB. The spectral-kinetic indicators of relaxation processes following the electron stabilization into the acceptor compartment of photosynthetic RCs of bacteria. DOKL BIOCHEM BIOPHYS 2014; 455:49-52. [PMID: 24795098 DOI: 10.1134/s1607672914020021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Indexed: 11/23/2022]
Affiliation(s)
- P P Knox
- Biological Faculty, Moscow State University, Moscow, 119992, Russia,
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Li K, Wang M, Wang J, Zhu R, Sun D, Sun X, Wang SL. Photoionization of Oxidized Coenzyme Q in Microemulsion: Laser Flash Photolysis Study in Biomembrane-like System. Photochem Photobiol 2012; 89:61-7. [DOI: 10.1111/j.1751-1097.2012.01180.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Gibasiewicz K, Pajzderska M, Karolczak J, Dobek A. Excitation and electron transfer in reaction centers from Rhodobacter sphaeroides probed and analyzed globally in the 1-nanosecond temporal window from 330 to 700 nm. Phys Chem Chem Phys 2009; 11:10484-93. [PMID: 19890535 DOI: 10.1039/b912431d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Global analysis of a set of room temperature transient absorption spectra of Rhodobacter sphaeroides reaction centers, recorded in wide temporal and spectral ranges and triggered by femtosecond excitation of accessory bacteriochlorophylls at 800 nm, is presented. The data give a comprehensive review of all spectral dynamics features in the visible and near UV, from 330 to 700 nm, related to the primary events in the Rb. sphaeroides reaction center: excitation energy transfer from the accessory bacteriochlorophylls (B) to the primary donor (P), primary charge separation between the primary donor and primary acceptor (bacteriopheophytin, H), and electron transfer from the primary to the secondary electron acceptor (ubiquinone). In particular, engagement of the accessory bacteriochlorophyll in primary charge separation is shown as an intermediate electron acceptor, and the initial free energy gap of approximately 40 meV, between the states P(+)B(A)(-) and P(+)H(A)(-) is estimated. The size of this gap is shown to be constant for the whole 230 ps lifetime of the P(+)H(A)(-) state. The ultrafast spectral dynamics features recorded in the visible range are presented against a background of results from similar studies performed for the last two decades.
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Affiliation(s)
- K Gibasiewicz
- Department of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznań, Poland.
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Gibasiewicz K, Pajzderska M, Ziółek M, Karolczak J, Dobek A. Internal Electrostatic Control of the Primary Charge Separation and Recombination in Reaction Centers from Rhodobacter sphaeroides Revealed by Femtosecond Transient Absorption. J Phys Chem B 2009; 113:11023-31. [DOI: 10.1021/jp811234q] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- K. Gibasiewicz
- Department of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznań, Poland
| | - M. Pajzderska
- Department of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznań, Poland
| | - M. Ziółek
- Department of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznań, Poland
| | - J. Karolczak
- Department of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznań, Poland
| | - A. Dobek
- Department of Physics, Adam Mickiewicz University, ul. Umultowska 85, 61-614 Poznań, Poland
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Knox PP, Krasilnikov PM, Mamonov PA, Seifullina NK, Uchoa AF, Baptista MS. Stabilization of the electron in the quinone acceptor part of the Rhodobacter sphaeroides reaction centers. Biophysics (Nagoya-shi) 2008. [DOI: 10.1134/s0006350908040106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Lefebvre-Legendre L, Rappaport F, Finazzi G, Ceol M, Grivet C, Hopfgartner G, Rochaix JD. Loss of phylloquinone in Chlamydomonas affects plastoquinone pool size and photosystem II synthesis. J Biol Chem 2007; 282:13250-63. [PMID: 17339322 DOI: 10.1074/jbc.m610249200] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phylloquinone functions as the electron transfer cofactor at the A(1) site of photosystem I. We have isolated and characterized a mutant of Chlamydomonas reinhardtii, menD1, that is deficient in MenD, which encodes 2-succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate synthase, an enzyme that catalyzes the first specific step of the phylloquinone biosynthetic pathway. The mutant is photosynthetically active but light-sensitive. Analysis of total pigments by mass spectrometry reveals that phylloquinone is absent in menD1, but plastoquinone levels are not affected. This is further confirmed by the rescue of menD1 by addition of phylloquinone to the growth medium. Analysis of electron transfer by absorption spectroscopy indicates that plastoquinone replaces phylloquinone in photosystem I and that electron transfer from A(1) to the iron-sulfur centers is slowed down at least 40-fold. Consistent with a replacement of phylloquinone by plastoquinone, the size of the free plastoquinone pool of menD1 is reduced by 20-30%. In contrast to cyanobacterial MenD-deficient mutants, photosystem I accumulates normally in menD1, whereas the level of photosystem II declines. This decrease is because of reduced synthesis of the photosystem II core subunits. The relationship between plastoquinone occupancy of the A(1) site in photosystem I and the reduced accumulation of photosystem II is discussed.
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Affiliation(s)
- Linnka Lefebvre-Legendre
- Department of Molecular Biology, University of Geneva, 30, Quai Ernest Ansermet 1211 Geneva 4, Switzerland
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Knox PP, Baptista MS, Uchoa AF, Zakharova NI. Effects of Oxygen, Heavy Water, and Glycerol on Electron Transfer in the Acceptor Part of Rhodobacter sphaeroides Reaction Centers. BIOCHEMISTRY (MOSCOW) 2005; 70:1268-73. [PMID: 16336188 DOI: 10.1007/s10541-005-0258-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The kinetics of electron transfer between primary and secondary quinone acceptors of the photosynthetic reaction center (RC) of the purple bacterium Rhodobacter sphaeroides wild type was studied at the wavelengths 400 and 450 nm. It was shown that removing of molecular oxygen from RC preparations slowed down the fast phase of the process from 4-4.5 microsec to tens of microseconds. Similar effects were observed after the incubation of RC in heavy water for 72 h or glycerol addition (90% v/v) to RC preparations. The observed effects are interpreted in terms of the influence of these agents on the hydrogen bond system of the RC. The state of this system can determine the formation of different RC conformations that are characterized by different rates of electron transfer between quinone acceptors.
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Affiliation(s)
- P P Knox
- Biology Faculty, Lomonosov Moscow State University, Moscow, 119992, Russia.
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11
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Sakuragi Y, Zybailov B, Shen G, Bryant DA, Golbeck JH, Diner BA, Karygina I, Pushkar Y, Stehlik D. Recruitment of a Foreign Quinone into the A1 Site of Photosystem I. J Biol Chem 2005; 280:12371-81. [PMID: 15681848 DOI: 10.1074/jbc.m412943200] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A photosystem I (PS I) complex containing plastoquinone-9 (PQ-9) but devoid of F(X), F(B), and F(A) was isolated and characterized from a mutant strain of Synechococcus sp. PCC 7002 in which the menB and rubA genes were insertionally inactivated. In isolated PS I trimers, the decay of P700+ measured in the near-IR and the decay of A1- measured in the near-UV were found to be biphasic, with (averaged) room temperature lifetimes of 12 and 350 micros. The decay-associated spectra of both kinetic phases are characteristic of the oxidized minus reduced difference spectrum of a semiquinone, consistent with charge recombination between P700+ and PQ-9-. The amplitude of the flash-induced absorbance changes in both the near-IR and the near-UV show that approximately one-half of the A1 binding sites are either empty or nonfunctional. A spin-polarized chlorophyll triplet is observed by time-resolved EPR, and it is attributed to the 3P700 product of P700+A0- charge recombination via the T0 spin level in those PS I complexes that do not contain a functional quinone. In those A1 sites that are occupied, the P700+Q- polarization pattern indicates that PQ-9 is oriented in a similar manner to that in the menB mutant. When excess 9,10-anthraquinone is added in vitro, it displaces PQ-9 and occupies the A1 binding site more readily than in the menB mutant. This can be explained by a greater accessibility to the A1 site in the menB rubA mutant due to the absence of F(X) and the stromal ridge polypeptides. The relatively low binding affinity of 9,10-anthraquinone allows it to be readily removed from the A1 site by washing. However, all A1 sites are shown to bind napthoquinones with high affinity and thus are proven to be functionally competent in quinone binding. The ability to readily displace PQ-9 from the A1 site makes the menB rubA mutant ideal for introducing novel quinones, particularly anthraquinones, into PS I.
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Affiliation(s)
- Yumiko Sakuragi
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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12
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Jay-gerin J, Abedinzadeh Z, Bensasson R. Radiat Phys Chem Oxf Engl 1993 2005; 72:69-71. [DOI: 10.1016/j.radphyschem.2004.09.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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14
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Satoh K, Ohno T, Katoh S. An oxygen-evolving complex with a simple subunit structure - ‘a water-plastoquinone oxidoreductase” - from the thermophilic cyanobacterium Synechococcus
sp. FEBS Lett 2001. [DOI: 10.1016/0014-5793(85)81096-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Mansfield R, Evans M. UV optical difference spectrum associated with the reduction of electron acceptor A1in photosystem I of higher plants. FEBS Lett 2001. [DOI: 10.1016/0014-5793(86)80747-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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17
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Nitschke W, Hauska G, Crofts AR. Fast electron transfer from low- to high-potential cytochromeb6in isolated cytochromeb6fcomplex. FEBS Lett 2001. [DOI: 10.1016/0014-5793(88)80417-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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18
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Knaff DB. The effect of pH on the midpoint oxidation-reduction potentials of components associated with plant photosystem II. FEBS Lett 2001. [DOI: 10.1016/0014-5793(75)80742-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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19
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Haveman J, Mathis P, Vermeglio A. Light-induced absorption changes in the near ultraviolet of the primary electron acceptor of photosystem II at liquid nitrogen temperature. FEBS Lett 2001. [DOI: 10.1016/0014-5793(75)80273-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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20
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Peluso A, Di Donato M, Saracino GAA. An alternative way of thinking about electron transfer in proteins: Proton assisted electron transfer between the primary and the secondary quinones in photosynthetic reaction centers. J Chem Phys 2000. [DOI: 10.1063/1.1286918] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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21
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Semenov AY, Vassiliev IR, van Der Est A, Mamedov MD, Zybailov B, Shen G, Stehlik D, Diner BA, Chitnis PR, Golbeck JH. Recruitment of a foreign quinone into the A1 site of photosystem I. Altered kinetics of electron transfer in phylloquinone biosynthetic pathway mutants studied by time-resolved optical, EPR, and electrometric techniques. J Biol Chem 2000; 275:23429-38. [PMID: 10801789 DOI: 10.1074/jbc.m000508200] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Interruption of the menA or menB gene in Synechocystis sp. PCC 6803 results in the incorporation of a foreign quinone, termed Q, into the A(1) site of photosystem I with a number of experimental indicators identifying Q as plastoquinone-9. A global multiexponential analysis of time-resolved optical spectra in the blue region shows the following three kinetic components: 1) a 3-ms lifetime in the absence of methyl viologen that represents charge recombination between P700(+) and an FeS(-) cluster; 2) a 750-microseconds lifetime that represents electron donation from an FeS(-) cluster to methyl viologen; and 3) an approximately 15-microseconds lifetime that represents an electrochromic shift of a carotenoid pigment. Room temperature direct detection transient EPR studies of forward electron transfer show a spectrum of P700(+) Q(-) during the lifetime of the spin polarization and give no evidence of a significant population of P700(+) FeS(-) for t </= 2-3 microseconds. The UV difference spectrum measured 5 microseconds after a flash shows a maximum at 315 nm, a crossover at 280 nm, and a minimum at 255 nm as well as a shoulder at 290-295 nm, all of which are characteristic of the plastoquinone-9 anion radical. Kinetic measurements that monitor Q at 315 nm show a major phase of forward electron transfer to the FeS clusters with a lifetime of approximately 15 microseconds, which matches the electrochromic shift at 485 nm of the carotenoid, as well as an minor phase with a lifetime of approximately 250 microseconds. Electrometric measurements show similar biphasic kinetics. The slower kinetic phase can be detected using time-resolved EPR spectroscopy and has a spectrum characteristic of a semiquinone anion radical. We estimate the redox potential of plastoquinone-9 in the A(1) site to be more oxidizing than phylloquinone so that electron transfer from Q(-) to F(X) is thermodynamically unfavorable in the menA and menB mutants.
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Affiliation(s)
- A Y Semenov
- A. N. Belozersky Institute of Physicochemical Biology, Moscow State University, 119899 Moscow, Russia
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Kropacheva TN, van Liemt WBS, Raap J, Lugtenburg J, Hoff AJ. Hydrogen-Bonding Effect on 13C and Proton Hyperfine Couplings of [4-13C]-Labeled Ubisemiquinones in Vitro. ACTA ACUST UNITED AC 1996. [DOI: 10.1021/jp960059l] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tatyana N. Kropacheva
- Department of Chemistry, Udmurt State University, Izhevsk, 426037 Russia, Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands, and Department of Biophysics, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands
| | - Willem B. S. van Liemt
- Department of Chemistry, Udmurt State University, Izhevsk, 426037 Russia, Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands, and Department of Biophysics, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands
| | - Jan Raap
- Department of Chemistry, Udmurt State University, Izhevsk, 426037 Russia, Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands, and Department of Biophysics, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands
| | - Johan Lugtenburg
- Department of Chemistry, Udmurt State University, Izhevsk, 426037 Russia, Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands, and Department of Biophysics, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands
| | - Arnold J. Hoff
- Department of Chemistry, Udmurt State University, Izhevsk, 426037 Russia, Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands, and Department of Biophysics, Leiden University, P.O. Box 9504, 2300 RA Leiden, The Netherlands
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Witt HT. Functional mechanism of water splitting photosynthesis. PHOTOSYNTHESIS RESEARCH 1991; 29:55-77. [PMID: 24415108 DOI: 10.1007/bf00035377] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/1991] [Accepted: 06/10/1991] [Indexed: 06/03/2023]
Abstract
A personal account is given on physico-chemical aspects of photosynthesis. The article starts with the way I entered the field of photosynthesis. Then, selected results from our research group are discussed. Three methods used for functional analysis in our laboratory are described: the repetitive flash spectroscopy; the electrochromic volt- and ammeter; and the membrane energization by a battery. Our subsequent studies deal with the two photoreaction centers, the primary charge separation, the plastoquinones as a transmembrane link between the two centers and the vectorial electron- and proton pathways. The results led to a picture of the elementary functional mechanism of the molecular machinery in the thylakoid membrane. The perspective then focuses on the coupling between the electric field, protons and phosphorylation. This section is followed by our observations and analysis of the mechanism of water cleavage and its coupling with the functioning of reaction center II. Finally, information is provided on structural aspects of the two reaction centers. The article ends with a retrospect.
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Affiliation(s)
- H T Witt
- Max-Volmer-Institut für Biophysikalische und Physikalische Chemie, Technische Universität Berlin, Straße des 17. Juni 135, D-1000, Berlin 12, Germany
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Gerken S, Dekker J, Schlodder E, Witt H. Studies on the multiphasic charge recombination between chlorophyll aII+ (P-680+) and plastoquinone QA− in photosystem II complexes. Ultraviolet difference spectrum of Chl-aII+/Chl-aII. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1989. [DOI: 10.1016/s0005-2728(89)80008-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Bibang R, Arnaud R, Lemaire J, Deflandre A, Lang G. Electron spin resonance of eumelanin from hair: photoinduced radicals in solid matrix. PIGMENT CELL RESEARCH 1989; 2:387-94. [PMID: 2555808 DOI: 10.1111/j.1600-0749.1989.tb00226.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
KBr matrices appear to be convenient media to reveal the radicals formed on light exposure of eumelanin dispersions. The ESR signal of eumelanin dispersed at low concentration in KBr pellets is analyzed during and after irradiation at various wavelengths. Different types of radicals are observed. R'1- and R1-types of radicals are assigned, respectively, to neutral and deprotonated intrinsic phenoxy radicals of eumelanin. R'1 can be oxidized by oxygen as opposite to R1. R2- and R'2-types are formed in the indolic site. Water favours the conversion of R2, unreactive with oxygen, into R'2 which can be oxidized. R'1 and R2 result of an electron photoejection, respectively, from the phenolic and the indolic site. The R3-type radicals are associated with the band-to-band excitation of eumelanin considered as a semiorganized solid.
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Affiliation(s)
- R Bibang
- Laboratoire de Photochimie Moléculaire et Macro-moléculaire (Unité Associée au C.N.R.S. N. 433), Université de Clermont II, Aubière, France
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Greenberg BM, Gaba V, Canaani O, Malkin S, Mattoo AK, Edelman M. Separate photosensitizers mediate degradation of the 32-kDa photosystem II reaction center protein in the visible and UV spectral regions. Proc Natl Acad Sci U S A 1989; 86:6617-20. [PMID: 2671998 PMCID: PMC297895 DOI: 10.1073/pnas.86.17.6617] [Citation(s) in RCA: 238] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
A component of the photosystem II reaction center, the 32-kDa protein, is rapidly turned over in the light. The mechanism of its light-dependent metabolism is largely unknown. We quantified the rate of 32-kDa protein degradation over a broad spectral range (UV, visible, and far red). The quantum yield for degradation was highest in the UVB (280-320 nm) region. Spectral evidence demonstrates two distinctly different photosensitizers for 32-kDa protein degradation. The data implicate the bulk photosynthetic pigments (primarily chlorophyll) in the visible and far red regions, and plastoquinone (in one or more of its redox states) in the UV region. A significant portion of 32-kDa protein degradation in sunlight is attributed to UVB irradiance.
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Affiliation(s)
- B M Greenberg
- Department of Plant Genetics, Weizmann Institute of Science, Rehovot, Israel
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27
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Mauzerall D, Greenbaum NL. The absolute size of a photosynthetic unit. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1989. [DOI: 10.1016/s0005-2728(89)80365-2] [Citation(s) in RCA: 112] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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28
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Diner BA, de Vitry C, Popot JL. Quinone exchange in the QA binding site of Photosystem II reaction center core preparations isolated from Chlamydomonas reinhardtii. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1988. [DOI: 10.1016/0005-2728(88)90118-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Mansfield RW, Nugent JH, Evans MC. ESR characteristics of Photosystem I in deuterium oxide: Further evidence that electron acceptor A1 is a quinone. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1987. [DOI: 10.1016/0005-2728(87)90131-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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30
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Yamagishi A, Fork DC. Photoreduction of QA, QB, and cytochrome b-559 in an oxygen-evolving photosystem II preparation from the thermophilic cyanobacterium Synechococcus sp. Arch Biochem Biophys 1987; 259:124-30. [PMID: 3120642 DOI: 10.1016/0003-9861(87)90477-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Light-induced absorption changes in an oxygen-evolving photosystem II (PS II) preparation from the thermophilic cyanobacterium Synechococcus sp. were analyzed using continuous illumination which caused the reduction of both QA (first stable quinone electron acceptor) and QB (second quinone electron acceptor of photosystem II). In this photosystem II preparation in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) the amount of QA was estimated to be 1 per 42 chlorophylls. In the absence of DCMU, plastoquinone (1.68 per QA) was photoreduced to plastohydroquinone within a few seconds, indicating that QB is reduced and protonated during this period. An electrochromic band shift centered around 685 nm was observed with and without DCMU. The extent of this band shift caused by QB reduction per electron was about a third or half of that caused by QA reduction. A significant amount of cytochrome b-559 (0.86 per QA) was photoreduced. Only 60% of the photoreduction of cytochrome b-559 was inhibited by a DCMU concentration that inhibited electron transfer beyond QB, indicating that the site of the reduction of cytochrome b-559 is located before the QB site and possibly on the donor side of PS II.
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Affiliation(s)
- A Yamagishi
- Department of Plant Biology, Carnegie Institution of Washington, Stanford, California 94305
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31
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McCauley S, Melis A. QUANTITATION OF PHOTOSYSTEM II ACTIVITY IN SPINACH CHLOROPLASTS. EFFECT OF ARTIFICIAL QUINONE ACCEPTORS. Photochem Photobiol 1987. [DOI: 10.1111/j.1751-1097.1987.tb04809.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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32
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Takamiya KI, Iba K, Okamura K. Reaction center complex from an aerobic photosynthetic bacterium, Erythrobacter species OCh 114. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1987. [DOI: 10.1016/0005-2728(87)90013-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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33
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Ohno T, Satoh K, Katoh S. Chemical composition of purified oxygen-evolving complexes from the thermophilic cyanobacterium Synechococcus sp. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90049-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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34
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Chen M, Zhu QS. Rapid redox equilibrium between the mitochondrial Q pool and cytochrome b during triphasic reduction of cytochrome b by succinate. BIOCHIMICA ET BIOPHYSICA ACTA 1986; 851:457-68. [PMID: 3019394 DOI: 10.1016/0005-2728(86)90082-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The reliability of monitoring the redox reactions of cytochrome b using the different wavelengths employed by different authors has been reexamined. It was found that 562-575 nm is suitable in succinate: cytochrome c reductase but not in mitochondria, in which case 562-540 nm is a better pair. Direct optical measurements of the redox reaction kinetics of the mitochondrial Q pool using a commercial dual-wavelength spectrophotometer are possible when succinate is used as the electron donor. Using the correct wavelength pair, and with malonate to slow down the electron input, the reduction course of cytochrome b was still triphasic but a plateau or a turn replaced the oxidation phase previously reported by several authors. At the same time, the reduction course of the Q pool was also triphasic, and in perfect match with that of cytochrome b. Destruction of the Rieske iron-sulfur cluster by British anti-Lewisite (BAL) + O2 treatment or prereduction of the high-potential components made the reduction of both Q and b monophasic. The plot of log (Q/QH2) against log (b3+/b2+) gave a straight line with an n value of 1.7 for cytochrome b at pH 7.4. This n value rose to 2.0 at pH 6.5 and dropped to 1.4 at pH 8.5. On the other hand, the mid-point potential of cytochrome b relative to that of the Q pool remained essentially unchanged between pH 6.5 and 8.4. BAL treatment had a small effect on the midpoint potential of cytochrome b relative to that of the Q pool and had no effect on the n value. Addition of quinone homologues and analogues extended the plateau phase in the reduction of cytochrome b, but exogenous quinones did not equilibrate rapidly with cytochrome b. It was concluded that the appearance of the plateau between the two reduction phases of Q and b is caused by the rapid delivery of electrons to the high-potential components of the respiratory chain as envisaged in the Q cycle; the unexpected n value for cytochrome b suggests a concerted reduction by QH2 of two species of cytochromes b-562.
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36
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A study of the kinetic properties of the stable semiquinone of the reaction-center secondary acceptor in chromatophores of non-sulfur purple bacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90106-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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37
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McCauley SW, Melis A. Quantitation of photosystem II in spinach chloroplasts. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90023-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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38
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Numbers and functions of plastoquinone molecules associated with photosystem II preparations from Synechococcus sp. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1986. [DOI: 10.1016/0005-2728(86)90040-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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39
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Nohl H, Jordan W, Youngman RJ. Quinones in Biology: Functions in electron transfer and oxygen activation. ACTA ACUST UNITED AC 1986. [DOI: 10.1016/s8755-9668(86)80030-8] [Citation(s) in RCA: 102] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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40
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Schatz GH, van Gorkom HJ. Absorbance difference spectra upon charge transfer to secondary donors and acceptors in Photosystem II. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1985. [DOI: 10.1016/0005-2728(85)90212-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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41
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Kleinfeld D, Okamura MY, Feher G. Charge recombination kinetics as a probe of protonation of the primary acceptor in photosynthetic reaction centers. Biophys J 1985; 48:849-52. [PMID: 3907729 PMCID: PMC1329411 DOI: 10.1016/s0006-3495(85)83844-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The kinetics of the charge recombination D+QA-----DQA was used to probe the protonation of the primary acceptor in reaction centers from Rhodopseudomonas sphaeroides, in which the native ubiquinone was replaced by anthraquinone. We found that QA- is stabilized by the rapid (t less than 10(-2) s) binding of a proton, with a pK of 9.8. The distance between QA- and the proton binding site was estimated to be larger than approximately 5 A.
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42
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Kleinfeld D, Okamura M, Feher G. Electron transfer in reaction centers of Rhodopseudomonas sphaeroides. II. Free energy and kinetic relations between the acceptor states QA−QB− and QAQ2−B. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1985; 809:291-310. [DOI: 10.1016/0005-2728(85)90179-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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43
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Snozzi M, Crofts AR. Kinetics of the c-cytochromes in chromatophores from Rhodopseudomonas sphaeroides as a function of the concentration of cytochrome c2. Influence of this concentration on the oscillation of the secondary acceptor of the reaction centers QB. BIOCHIMICA ET BIOPHYSICA ACTA 1985; 809:260-70. [PMID: 2994721 DOI: 10.1016/0005-2728(85)90069-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The oxidation kinetics of Cyt c1 and c2 have been measured in normal chromatophores and in chromatophores fused with liposomes in order to increase the internal volume. The kinetics of Cyt c1 oxidation were found to be dependent on Cyt c2 concentration. The initial rate of Cyt c1 oxidation decreased after fusion by a factor of about two, indicating a process dependent on diffusion. The results do not allow a clear distinction between a diffusion of Cyt c2 along the inner membrane surface or through the inner volume of the vesicle; two- and three-dimensional models are discussed. In contrast to Cyt c1, the kinetics of oxidation of Cyt c2 were not influenced by changes in concentration. It is concluded that reduced Cyt c2 is preferentially bound to the reaction centers. A binary pattern as a function of flash number from the dark-adapted state was measured in the turn-over of the two-electron gate of the reaction center. In chromatophores with more than 0.5 cytochrome c2 molecules per reaction center, this binary pattern titrated out with a midpoint around 340 mV on reduction of the suspension. In experiments with chromatophores with a low Cyt c2 content, or with spheroplast-derived vesicles which had lost Cyt c2, the binary oscillation in the two-electron gate could be observed at much lower potentials. The results suggest that the binding of reduced cytochrome c2 modifies the behavior of the two-electron gate. A model in which reaction center dimers are stabilized by Cyt c2 is proposed to explain the effect.
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44
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45
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Partial purification and characterization of glutaryl-coenzyme A dehydrogenase, electron transfer flavoprotein, and electron transfer flavoprotein-Q oxidoreductase from Paracoccus denitrificans. J Bacteriol 1985; 163:709-15. [PMID: 2991202 PMCID: PMC219179 DOI: 10.1128/jb.163.2.709-715.1985] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Glutaryl-coenzyme A (CoA) dehydrogenase and the electron transfer flavoprotein (ETF) of Paracoccus denitrificans were purified to homogeneity from cells grown with glutaric acid as the carbon source. Glutaryl-CoA dehydrogenase had a molecular weight of 180,000 and was made up of four identical subunits with molecular weights of about 43,000 each of which contained one flavin adenine dinucleotide molecule. The enzyme catalyzed an oxidative decarboxylation of glutaryl-CoA to crotonyl-CoA, was maximally stable at pH 5.0, and lost activity readily at pH values above 7.0. The enzyme had a pH optimum in the range of 8.0 to 8.5, a catalytic center activity of about 960 min-1, and apparent Michaelis constants for glutaryl-CoA and pig liver ETF of about 1.2 and 2.5 microM, respectively. P. denitrificans ETF had a visible spectrum identical to that of pig liver ETF and was made up of two subunits, only one of which contained a flavin adenine dinucleotide molecule. The isoelectric point of P. denitrificans ETF was 4.45 compared with 6.8 for pig liver ETF. P. denitrificans ETF accepted electrons not only from P. denitrificans glutaryl-CoA dehydrogenase, but also from the pig liver butyryl-CoA and octanoyl-CoA dehydrogenases. The apparent Vmax was of similar magnitude with either pig liver or P. denitrificans ETF as an electron acceptor for these dehydrogenases. P. denitrificans glutaryl-CoA dehydrogenase and ETF were used to assay for the reduction of ubiquinone 1 by ETF-Q oxidoreductase in cholate extracts of P. denitrificans membranes. The ETF-Q oxidoreductase from P. denitrificans could accept electrons from either the bacterial or the pig liver ETF. In either case, the apparent Km for ETF was infinitely high. P. denitrificans ETF-Q oxidoreductase was purified from contaminating paramagnets, and the resultant preparation had electron paramagnetic resonance signals at 2.081, 1.938, and 1.879 G, similar to those of the mitochondrial enzyme.
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46
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Dennenberg R, Jursinic P. A comparison of the absorption changes near 325 nm and chlorophyll a fluorescence characteristics of the Photosystem II acceptors Qa and Q400. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1985. [DOI: 10.1016/0005-2728(85)90043-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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47
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Yamagishi A, Katoh S. Further characterization of the two Photosystem II reaction center complex preparations from the thermophilic cyanobacterium Synechococcus sp. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1985. [DOI: 10.1016/0005-2728(85)90054-4] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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48
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Kleinfeld D, Okamura MY, Feher G. Electron transfer in reaction centers of Rhodopseudomonas sphaeroides. I. Determination of the charge recombination pathway of D+QAQ(-)B and free energy and kinetic relations between Q(-)AQB and QAQ(-)B. BIOCHIMICA ET BIOPHYSICA ACTA 1984; 766:126-40. [PMID: 6331502 DOI: 10.1016/0005-2728(84)90224-x] [Citation(s) in RCA: 205] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The electron-transfer reactions and thermodynamic equilibria involving the quinone acceptor complex in bacterial reaction centers from R. sphaeroides were investigated. The reactions are described by the scheme: (Formula: see text). We found that the charge recombination pathway of D+QAQ(-)B proceeds via the intermediate state D+Q(-)AQB, the direct pathway contributing less than approx. 5% to the observed recombination rate. The method used to obtain this result was based on a comparison of the kinetics predicted for the indirect pathway (given by the product kAD-times the fraction of reaction centers in the Q-AQB state) with the observed recombination rate, kobsD+----D. The kinetic measurements were used to obtain the pH dependence (6.1 smaller than or equal to pH smaller than or equal to 11.7) of the free energy difference between the states Q(-)AQB and QAQ(-)B. At low pH (less than 9) QAQ(-)B is stabilized relative to Q(-)AQB by 67 meV, whereas at high pH Q(-)AQB is energetically favored. Both Q(-)A and Q(-)B associate with a proton, with pK values of 9.8 and 11.3, respectively. The stronger interaction of the proton with Q(-)B provides the driving force for the forward electron transfer.
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49
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Rich PR. Electron and proton transfers through quinones and cytochrome bc complexes. BIOCHIMICA ET BIOPHYSICA ACTA 1984; 768:53-79. [PMID: 6322844 DOI: 10.1016/0304-4173(84)90007-7] [Citation(s) in RCA: 266] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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50
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Optical characterization of Photosystem II electron donors. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1984. [DOI: 10.1016/0005-2728(84)90100-2] [Citation(s) in RCA: 180] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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