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Guerra WD, Odella E, Cui K, Secor M, Dominguez RE, Gonzalez EJ, Moore TA, Hammes-Schiffer S, Moore AL. The role of an intramolecular hydrogen bond in the redox properties of carboxylic acid naphthoquinones. Chem Sci 2024:d4sc05277c. [PMID: 39371459 PMCID: PMC11445641 DOI: 10.1039/d4sc05277c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2024] [Accepted: 09/19/2024] [Indexed: 10/08/2024] Open
Abstract
A bioinspired naphthoquinone model of the quinones in photosynthetic reaction centers but bearing an intramolecular hydrogen-bonded carboxylic acid has been synthesized and characterized electrochemically, spectroscopically, and computationally to provide mechanistic insight into the role of proton-coupled electron transfer (PCET) of quinone reduction in photosynthesis. The reduction potential of this construct is 370 mV more positive than the unsubstituted naphthoquinone. In addition to the reversible cyclic voltammetry, infrared spectroelectrochemistry confirms that the naphthoquinone/naphthoquinone radical anion couple is fully reversible. Calculated redox potentials agree with the experimental trends arising from the intramolecular hydrogen bond. Molecular electrostatic potentials illustrate the reversible proton transfer driving forces, and analysis of the computed vibrational spectra supports the possibility of a combination of electron transfer and PCET processes. The significance of PCET, reversibility, and redox potential management relevant to the design of artificial photosynthetic assemblies involving PCET processes is discussed.
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Affiliation(s)
- Walter D Guerra
- School of Molecular Sciences, Arizona State University Tempe Arizona 85287-1604 USA
| | - Emmanuel Odella
- School of Molecular Sciences, Arizona State University Tempe Arizona 85287-1604 USA
| | - Kai Cui
- Department of Chemistry, Princeton University Princeton New Jersey 08544 USA
| | - Maxim Secor
- Department of Chemistry, Princeton University Princeton New Jersey 08544 USA
| | - Rodrigo E Dominguez
- School of Molecular Sciences, Arizona State University Tempe Arizona 85287-1604 USA
| | - Edwin J Gonzalez
- School of Molecular Sciences, Arizona State University Tempe Arizona 85287-1604 USA
| | - Thomas A Moore
- School of Molecular Sciences, Arizona State University Tempe Arizona 85287-1604 USA
| | | | - Ana L Moore
- School of Molecular Sciences, Arizona State University Tempe Arizona 85287-1604 USA
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2
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Jia QQ, Zhang XJ, Zhu L, Huang LZ. Fe(II) coordination transition regulates reductive dechlorination: The overlooked abiotic role of lactate. WATER RESEARCH 2024; 254:121342. [PMID: 38428238 DOI: 10.1016/j.watres.2024.121342] [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: 11/24/2023] [Revised: 01/29/2024] [Accepted: 02/18/2024] [Indexed: 03/03/2024]
Abstract
The coordination environment of Fe(II) significantly affect the reductive reactivity of Fe(II). Lactate is a common substrate for enhancing microbial dechlorination, but its effect on abiotic Fe(II)-driven reductive dechlorination is largely ignored. In this study, the structure-reactivity relationship of Fe(II) is investigated by regulating the ratio of lactate:Fe(II). This work shows that lactate-Fe(II) complexing enhances the abiotic Fe(II)-driven reductive dechlorination with the optimum lactate:Fe(II) ratio of 10:20. The formed hydrogen bond (Fe-OH∙∙∙∙∙∙O = C-) and Fe-O-C metal-ligand bond result in a reduced Fe(II) coordination number from six to four, which lead to the transition of Fe(II) coordination geometry from octahedron to tetrahedron/square planar. Coordinatively unsaturated Fe(II) results in the highest reductive dechlorination reactivity towards carbon tetrachloride (k1 = 0.26254 min-1). Excessive lactate concentration (> 10 mM) leads to an increased Fe(II) coordination number from four to six with a decreased reductive reactivity. Electrochemical characterization and XPS results show that lactate-Fe(II)-I (C3H5O3-:Fe(II) = 10:20) has the highest electron-donating capacity. This study reveals the abiotic effect of lactate on reductive dechlorination in a subsurface-reducing environment where Fe(II) is usually abundant.
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Affiliation(s)
- Qian-Qian Jia
- School of Civil Engineering, Wuhan University, No. 8, East Lake South Road, Wuhan, China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, 430072 China; School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212100, China
| | - Xue-Jie Zhang
- School of Civil Engineering, Wuhan University, No. 8, East Lake South Road, Wuhan, China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, 430072 China
| | - Liandong Zhu
- School of Resources & Environmental Science, Hubei International Scientific and Technological Cooperation Base of Sustainable Resource and Energy, Hubei Key Laboratory of Biomass-Resources Chemistry and Environmental Biotechnology, Wuhan University, Wuhan 430079, China
| | - Li-Zhi Huang
- School of Civil Engineering, Wuhan University, No. 8, East Lake South Road, Wuhan, China; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, 430072 China.
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3
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Fresch E, Collini E. The Role of H-Bonds in the Excited-State Properties of Multichromophoric Systems: Static and Dynamic Aspects. Molecules 2023; 28:molecules28083553. [PMID: 37110786 PMCID: PMC10141795 DOI: 10.3390/molecules28083553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/12/2023] [Accepted: 04/15/2023] [Indexed: 04/29/2023] Open
Abstract
Given their importance, hydrogen bonds (H-bonds) have been the subject of intense investigation since their discovery. Indeed, H-bonds play a fundamental role in determining the structure, the electronic properties, and the dynamics of complex systems, including biologically relevant materials such as DNA and proteins. While H-bonds have been largely investigated for systems in their electronic ground state, fewer studies have focused on how the presence of H-bonds could affect the static and dynamic properties of electronic excited states. This review presents an overview of the more relevant progress in studying the role of H-bond interactions in modulating excited-state features in multichromophoric biomimetic complex systems. The most promising spectroscopic techniques that can be used for investigating the H-bond effects in excited states and for characterizing the ultrafast processes associated with their dynamics are briefly summarized. Then, experimental insights into the modulation of the electronic properties resulting from the presence of H-bond interactions are provided, and the role of the H-bond in tuning the excited-state dynamics and the related photophysical processes is discussed.
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Affiliation(s)
- Elisa Fresch
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Elisabetta Collini
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy
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4
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Bangade VM, Mali PR, Meshram HM. Synthesis of Potent Anticancer Substituted 5-Benzimidazol-2-amino Thiazoles Controlled by Bifunctional Hydrogen Bonding under Microwave Irradiations. J Org Chem 2021; 86:6056-6065. [PMID: 33872008 DOI: 10.1021/acs.joc.0c02542] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Benzimidazol-amino thiazoles are synthesized under microwave irradiations using benzimidazole phenyl thiourea and 2-bromoacetophenone. Bifunctional hydrogen bonding plays an important role in chemical conversion. The reaction was carried out by C-C bond formation, followed by C-N bond cleavage and simultaneous migration of the benzimidazole ring. This reaction is novel and efficient for the synthesis of benzimidazol-amino thiazoles in which microwaves were used as driving forces. Synthesis of the product was controlled by double hydrogen bonding which is practically confirmed by the synthesis of routine imino-thiazole as an alternative product in the simple acidic condition. The simple acidic condition is neither responsible nor sufficient for optimum conversion of the benzimidazole migrated product. The synthesized products benzimidazole amino thiazoles D4 (IC50 = 4.207 μM) and D8 (IC50 = 2.398 μM) show interesting anticancer activities for human lung cancer with reference to doxorubicin (IC50 = 1.750 μM).
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Affiliation(s)
- Vikas M Bangade
- Medicinal Chemistry and Pharmacology Division, Indian Institute of Chemical Technology, Hyderabad, 500 607, India.,Department of Chemistry, The Institute of Science, Mumbai, Dr. Homi Bhabha State University, Mumbai, 15, Madame Cama Road, Mumbai, 32, India
| | - Prakash R Mali
- Medicinal Chemistry and Pharmacology Division, Indian Institute of Chemical Technology, Hyderabad, 500 607, India
| | - Harshadas M Meshram
- Medicinal Chemistry and Pharmacology Division, Indian Institute of Chemical Technology, Hyderabad, 500 607, India
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5
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Fresch E, Peruffo N, Trapani M, Cordaro M, Bella G, Castriciano MA, Collini E. The effect of hydrogen bonds on the ultrafast relaxation dynamics of a BODIPY dimer. J Chem Phys 2021; 154:084201. [PMID: 33639732 DOI: 10.1063/5.0038242] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The influence of hydrogen bonds (H-bonds) in the structure, dynamics, and functionality of biological and artificial complex systems is the subject of intense investigation. In this broad context, particular attention has recently been focused on the ultrafast H-bond dependent dynamical properties in the electronic excited state because of their potentially dramatic consequences on the mechanism, dynamics, and efficiency of photochemical reactions and photophysical processes of crucial importance for life and technology. Excited-state H-bond dynamics generally occur on ultrafast time scales of hundreds of femtoseconds or less, making the characterization of associated mechanisms particularly challenging with conventional time-resolved techniques. Here, 2D electronic spectroscopy is exploited to shed light on this still largely unexplored dynamic mechanism. An H-bonded molecular dimer prepared by self-assembly of two boron-dipyrromethene dyes has been specifically designed and synthesized for this aim. The obtained results confirm that upon formation of H-bonds and the dimer, a new ultrafast relaxation channel is activated in the ultrafast dynamics, mediated by the vibrational motions of the hydrogen donor and acceptor groups. This relaxation channel also involves, beyond intra-molecular relaxations, an inter-molecular transfer process. This is particularly significant considering the long distance between the centers of mass of the two molecules. These findings suggest that the design of H-bonded structures is a particularly powerful tool to drive the ultrafast dynamics in complex materials.
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Affiliation(s)
- Elisa Fresch
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy
| | - Nicola Peruffo
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy
| | - Mariachiara Trapani
- CNR-ISMN, Istituto per lo Studio dei Materiali Nanostrutturati, c/o Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, V.le F. Stagno D'Alcontres 31, 98166 Messina, Italy
| | - Massimiliano Cordaro
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, V.le F. Stagno D'Alcontres 31, 98166 Messina, Italy
| | - Giovanni Bella
- Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, Università di Messina, V.le F. Stagno D'Alcontres 31, 98166 Messina, Italy
| | - Maria Angela Castriciano
- CNR-ISMN, Istituto per lo Studio dei Materiali Nanostrutturati, c/o Dipartimento di Scienze Chimiche, Biologiche, Farmaceutiche ed Ambientali, V.le F. Stagno D'Alcontres 31, 98166 Messina, Italy
| | - Elisabetta Collini
- Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy
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Strakhovskaya MG, Lukashev EP, Korvatovskiy BN, Kholina EG, Seifullina NK, Knox PP, Paschenko VZ. The effect of some antiseptic drugs on the energy transfer in chromatophore photosynthetic membranes of purple non-sulfur bacteria Rhodobacter sphaeroides. PHOTOSYNTHESIS RESEARCH 2021; 147:197-209. [PMID: 33389445 PMCID: PMC7778420 DOI: 10.1007/s11120-020-00807-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
Chromatophores of purple non-sulfur bacteria (PNSB) are invaginations of the cytoplasmic membrane that contain a relatively simple system of light-harvesting protein-pigment complexes, a photosynthetic reaction center (RC), a cytochrome complex, and ATP synthase, which transform light energy into the energy of synthesized ATP. The high content of negatively charged phosphatidylglycerol (PG) and cardiolipin (CL) in PNSB chromatophore membranes makes these structures potential targets that bind cationic antiseptics. We used the methods of stationary and kinetic fluorescence spectroscopy to study the effect of some cationic antiseptics (chlorhexidine, picloxydine, miramistin, and octenidine at concentrations up to 100 μM) on the spectral and kinetic characteristics of the components of the photosynthetic apparatus of Rhodobacter sphaeroides chromatophores. Here we present the experimental data on the reduced efficiency of light energy conversion in the chromatophore membranes isolated from the photosynthetic bacterium Rb. sphaeroides in the presence of cationic antiseptics. The addition of antiseptics did not affect the energy transfer between the light-harvesting LH1 complex and reaction center (RC). However, it significantly reduced the efficiency of the interaction between the LH2 and LH1 complexes. The effect was maximal with 100 μM octenidine. It has been proved that molecules of cationic antiseptics, which apparently bind to the heads of negatively charged cardiolipin molecules located in the rings of light-harvesting pigments on the cytoplasmic surface of the chromatophores, can disturb the optimal conditions for efficient energy migration in chromatophore membranes.
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Affiliation(s)
- Marina G Strakhovskaya
- Biophysics Department, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119234.
- Federal Scientific and Clinical Center of Specialized Types of Medical Care and Medical Technologies of the Federal Medical and Biological Agency of Russia, Moscow, Russian Federation.
| | - Eugene P Lukashev
- Biophysics Department, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Boris N Korvatovskiy
- Biophysics Department, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Ekaterina G Kholina
- Biophysics Department, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Nuranija Kh Seifullina
- Biophysics Department, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Peter P Knox
- Biophysics Department, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - Vladimir Z Paschenko
- Biophysics Department, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
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7
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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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8
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Knox PP, Gorokhov VV, Korvatovskiy BN, Lukashev EP, Goryachev SN, Paschenko VZ, Rubin AB. The effect of light and temperature on the dynamic state of Rhodobacter sphaeroides reaction centers proteins determined from changes in tryptophan fluorescence lifetime and P +Q A- recombination kinetics. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 180:140-148. [PMID: 29413697 DOI: 10.1016/j.jphotobiol.2018.01.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 01/22/2018] [Accepted: 01/29/2018] [Indexed: 11/26/2022]
Abstract
The temperature dependencies of the rate of dark recombination of separated charges between the photoactive bacteriochlorophyll and the primary quinone acceptor (QA) in photosynthetic reaction centers (RCs) of the purple bacteria Rhodobacter sphaeroides (Rb. sphaeroides) were investigated. Measurements were performed in water-glycerol and trehalose environments after freezing to -180 °C in the dark and under actinic light with subsequent heating. Simultaneously, the RC tryptophanyl fluorescence lifetime in the spectral range between 323 and 348 nm was measured under these conditions. A correlation was found between the temperature dependencies of the functional and dynamic parameters of RCs in different solvent mixtures. For the first time, differences in the average fluorescence lifetime of tryptophanyl residues were measured between RCs frozen in the dark and in the actinic light. The obtained results can be explained by the RC transitions between different conformational states and the dynamic processes in the structure of the hydrogen bonds of RCs. We assumed that RCs exist in two main microconformations - "fast" and "slow", which are characterized by different rates of P+ and QA- recombination reactions. The "fast" conformation is induced in frozen RCs in the dark, while the "slow" conformation of RC occurs when the RC preparation is frozen under actinic light. An explanation of the temperature dependencies of tryptophan fluorescence lifetimes in RC proteins was made under the assumption that temperature changes affect mainly the electron transfer from the indole ring of the tryptophan molecule to the nearest amide or carboxyl groups.
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Affiliation(s)
- Peter P Knox
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Vladimir V Gorokhov
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Boris N Korvatovskiy
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Eugene P Lukashev
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Sergey N Goryachev
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Vladimir Z Paschenko
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, 119991 Moscow, Russia.
| | - Andrew B Rubin
- Department of Biophysics, Biological Faculty of the M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
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9
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Knox PP, Lukashev EP, Korvatovskii BN, Gorokhov VV, Grishanova NP, Seyfullina NK, Paschenko VZ, Rubin AB. A comparison of the temperature dependence of charge recombination in the ion-radical pair P870+QA - and tryptophan fluorescence in the photosynthetic reaction centers of Rhodobacter sphaeroides. Biophysics (Nagoya-shi) 2017. [DOI: 10.1134/s0006350916060191] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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10
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Purple-bacterial photosynthetic reaction centers and quantum‐dot hybrid‐assemblies in lecithin liposomes and thin films. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2016; 164:73-82. [DOI: 10.1016/j.jphotobiol.2016.09.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 09/06/2016] [Indexed: 11/18/2022]
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Giustini M, Parente M, Mallardi A, Palazzo G. Effect of ionic strength on intra-protein electron transfer reactions: The case study of charge recombination within the bacterial reaction center. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1541-1549. [PMID: 27297026 DOI: 10.1016/j.bbabio.2016.06.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 06/06/2016] [Accepted: 06/09/2016] [Indexed: 11/27/2022]
Abstract
It is a common believe that intra-protein electron transfer (ET) involving reactants and products that are overall electroneutral are not influenced by the ions of the surrounding solution. The results presented here show an electrostatic coupling between the ionic atmosphere surrounding a membrane protein (the reaction center (RC) from the photosynthetic bacterium Rhodobacter sphaeroides) and two very different intra-protein ET processes taking place within it. Specifically we have studied the effect of salt concentration on: i) the kinetics of the charge recombination between the reduced primary quinone acceptor QA(-) and the primary photoxidized donor P(+); ii) the thermodynamic equilibrium (QA(-)↔QB(-)) for the ET between QA(-) and the secondary quinone acceptor QB. A distinctive point of this investigation is that reactants and products are overall electroneutral. The protein electrostatics has been described adopting the lowest level of complexity sufficient to grasp the experimental phenomenology and the impact of salt on the relative free energy level of reactants and products has been evaluated according to suitable thermodynamic cycles. The ionic strength effect was found to be independent on the ion nature for P(+)QA(-) charge recombination where the leading electrostatic term was the dipole moment. In the case of the QA(-)↔QB(-) equilibrium, the relative stability of QA(-) and QB(-) was found to depend on the salt concentration in a fashion that is different for chaotropic and kosmotropic ions. In such a case both dipole moment and quadrupole moments of the RC must be considered.
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Affiliation(s)
- Mauro Giustini
- Chemistry Department, University of Rome "La Sapienza", Italy; CSGI (Center for Colloid and Surface Science), c/o Dept. Chemistry, via Orabona 4, 70125 Bari, Italy.
| | - Matteo Parente
- Dutch Institute for Fundamental Energy Research (DIFFER), De Zaale 20, 5612, AJ, Eindhoven, The Netherlands
| | - Antonia Mallardi
- CNR-IPCF, Istituto per i processi chimico fisici, c/o Dept. Chemistry, via Orabona 4, 70125 Bari, Italy
| | - Gerardo Palazzo
- Chemistry Department, University of Bari, via Orabona 4, 70125 Bari, Italy; CSGI (Center for Colloid and Surface Science), c/o Dept. Chemistry, via Orabona 4, 70125 Bari, Italy.
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12
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Bull JN, West CW, Verlet JRR. Ultrafast dynamics of formation and autodetachment of a dipole-bound state in an open-shell π-stacked dimer anion. Chem Sci 2016; 7:5352-5361. [PMID: 30155188 PMCID: PMC6020752 DOI: 10.1039/c6sc01062h] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 04/23/2016] [Indexed: 12/15/2022] Open
Abstract
Isolated π-stacked dimer radical anions present the simplest model of an excess electron in a π-stacked environment. Here, frequency-, angle-, and time-resolved photoelectron imaging together with electronic structure calculations have been used to characterise the π-stacked coenzyme Q0 dimer radical anion and its exited state dynamics. In the ground electronic state, the excess electron is localised on one monomer with a planar para-quinone ring, which is solvated by the second monomer in which carbonyl groups are bent out of the para-quinone ring plane. Through the π-stacking interaction, the dimer anion exhibits a number of charge-transfer (intermolecular) valence-localised resonances situated in the detachment continuum that undergo efficient internal conversion to a cluster dipole-bound state (DBS) on a ∼60 fs timescale. In turn, the DBS undergoes vibration-mediated autodetachment on a 2.0 ± 0.2 ps timescale. Experimental vibrational structure and supporting calculations assign the intermolecular dynamics to be facilitated by vibrational wagging modes of the carbonyl groups on the non-planar monomer. At photon energies ∼0.6-1.0 eV above the detachment threshold, a competition between photoexcitation of an intermolecular resonance leading to the DBS, and photoexcitation of an intramolecular resonance leading to monomer-like dynamics further illustrates the π-stacking specific dynamics. Overall, this study provides the first direct observation of both internal conversion of resonances into a DBS, and characterisation of a vibration-mediated autodetachment in real-time.
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Affiliation(s)
- James N Bull
- Department of Chemistry , Durham University , South Road , Durham DH1 3LE , UK .
| | - Christopher W West
- Department of Chemistry , Durham University , South Road , Durham DH1 3LE , UK .
| | - Jan R R Verlet
- Department of Chemistry , Durham University , South Road , Durham DH1 3LE , UK .
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13
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Mittra K, Sengupta K, Singha A, Bandyopadhyay S, Chatterjee S, Rana A, Samanta S, Dey A. Second sphere control of spin state: Differential tuning of axial ligand bonds in ferric porphyrin complexes by hydrogen bonding. J Inorg Biochem 2016; 155:82-91. [DOI: 10.1016/j.jinorgbio.2015.11.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Revised: 10/02/2015] [Accepted: 11/10/2015] [Indexed: 11/16/2022]
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14
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Lukashev EP, Knox PP, Krasilnikov PM, Seifullina NK, Rubin AB. Mechanisms of anomalous temperature dependence of the recombination of the photoseparated charges between bacteriochlorophyll and primary quinone in Rb. sphaeroides: The role of RC hydrogen bonds. DOKL BIOCHEM BIOPHYS 2015; 459:199-203. [PMID: 25559979 DOI: 10.1134/s1607672914060052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Indexed: 11/23/2022]
Affiliation(s)
- E P Lukashev
- Department of Biophysics, Biological Faculty, Moscow State University, Moscow, 119992, Russia
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15
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Zagidullin VE, Lukashev EP, Knox PP, Seifullina NK, Sokolova OS, Pechnikova EV, Lokstein H, Paschenko VZ. Properties of hybrid hybrid complexes composed of photosynthetic reaction centers from the purple bacterium Rhodobacter sphaeroides and quantum dots in lecithin liposomes. BIOCHEMISTRY (MOSCOW) 2014; 79:1183-91. [DOI: 10.1134/s0006297914110054] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Krasilnikov PM. Two-dimensional model of a double-well potential: Proton transfer upon hydrogen bond deformation. Biophysics (Nagoya-shi) 2014. [DOI: 10.1134/s0006350914020158] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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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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Krasilnikov PM. Problems of the theory of electron transfer in biological systems. Biophysics (Nagoya-shi) 2014. [DOI: 10.1134/s0006350914010059] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Krasilnikov PM, Knox PP, Rubin AB. A mechanism stabilizing a long-lived charge-separated state of photosynthetic reaction centers frozen under intense illumination. Biophysics (Nagoya-shi) 2013. [DOI: 10.1134/s000635091304009x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Krasilnikov PM. Theory of intermolecular electron transfer in nanoscale biological structures. Biophysics (Nagoya-shi) 2011. [DOI: 10.1134/s0006350911050095] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Knox PP, Lukashev EP, Simanova AV, Krupyanskii YF, Loiko NG, El’-Registan GI, Rubin AB. The influence of alkylhydroxybenzenes on electron stabilization processes in the quinone acceptor portion of the reaction centers of the bacterium Rhodobacter sphaeroides. Microbiology (Reading) 2010. [DOI: 10.1134/s0026261710020190] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Krasilnikov PM, Knox PP, Rubin AB. Relaxation mechanism of molecular systems containing hydrogen bonds and free energy temperature dependence of reaction of charges recombination within Rhodobacter sphaeroides RC. Photochem Photobiol Sci 2009; 8:181-95. [PMID: 19247510 DOI: 10.1039/b811014j] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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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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Palazzo G, Francia F, Mallardi A, Giustini M, Lopez F, Venturoli G. Water Activity Regulates the QA− to QB Electron Transfer in Photosynthetic Reaction Centers from Rhodobacter sphaeroides. J Am Chem Soc 2008; 130:9353-63. [DOI: 10.1021/ja801963a] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Gerardo Palazzo
- Dipartimento di Chimica and CSGI, Università di Bari, via Orabona 4, I-70126, Bari, Italy, Dipartimento di Biologia and CNISM, Università di Bologna, Italy, Istituto per i Processi Chimico-Fisici, CNR, via Orabona 4, 70126 Bari, Italy, and CSGI and Dipartimento di Chimica, Università “La Sapienza”, I-00185 Roma, Italy
| | - Francesco Francia
- Dipartimento di Chimica and CSGI, Università di Bari, via Orabona 4, I-70126, Bari, Italy, Dipartimento di Biologia and CNISM, Università di Bologna, Italy, Istituto per i Processi Chimico-Fisici, CNR, via Orabona 4, 70126 Bari, Italy, and CSGI and Dipartimento di Chimica, Università “La Sapienza”, I-00185 Roma, Italy
| | - Antonia Mallardi
- Dipartimento di Chimica and CSGI, Università di Bari, via Orabona 4, I-70126, Bari, Italy, Dipartimento di Biologia and CNISM, Università di Bologna, Italy, Istituto per i Processi Chimico-Fisici, CNR, via Orabona 4, 70126 Bari, Italy, and CSGI and Dipartimento di Chimica, Università “La Sapienza”, I-00185 Roma, Italy
| | - Mauro Giustini
- Dipartimento di Chimica and CSGI, Università di Bari, via Orabona 4, I-70126, Bari, Italy, Dipartimento di Biologia and CNISM, Università di Bologna, Italy, Istituto per i Processi Chimico-Fisici, CNR, via Orabona 4, 70126 Bari, Italy, and CSGI and Dipartimento di Chimica, Università “La Sapienza”, I-00185 Roma, Italy
| | - Francesco Lopez
- Dipartimento di Chimica and CSGI, Università di Bari, via Orabona 4, I-70126, Bari, Italy, Dipartimento di Biologia and CNISM, Università di Bologna, Italy, Istituto per i Processi Chimico-Fisici, CNR, via Orabona 4, 70126 Bari, Italy, and CSGI and Dipartimento di Chimica, Università “La Sapienza”, I-00185 Roma, Italy
| | - Giovanni Venturoli
- Dipartimento di Chimica and CSGI, Università di Bari, via Orabona 4, I-70126, Bari, Italy, Dipartimento di Biologia and CNISM, Università di Bologna, Italy, Istituto per i Processi Chimico-Fisici, CNR, via Orabona 4, 70126 Bari, Italy, and CSGI and Dipartimento di Chimica, Università “La Sapienza”, I-00185 Roma, Italy
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Natale D, Mareque-Rivas JC. The combination of transition metal ions and hydrogen-bonding interactions. Chem Commun (Camb) 2007:425-37. [PMID: 18188459 DOI: 10.1039/b709650j] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This feature article presents an overview of the types of hydrogen bonding interactions involving metal complexes and their functional effects. It shows with recent examples why hydrogen bonds have become a crucial functional and structural element in modern inorganic chemistry. The relevance of this combination in tackling current chemistry challenges such as energy production and the development of new materials and more effective catalysts, sensors and medicines is illustrated.
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Affiliation(s)
- Daniela Natale
- School of Chemistry, The University of Edinburgh, Edinburgh, UK
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