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Beauzamy L, Longatte G, Guille-Collignon M, Lemaître F. Investigation of quinone reduction by microalgae using fluorescence - do "lake" and "puddle" mechanisms matter? Bioelectrochemistry 2023; 152:108454. [PMID: 37172391 DOI: 10.1016/j.bioelechem.2023.108454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 04/25/2023] [Accepted: 04/26/2023] [Indexed: 05/15/2023]
Abstract
Photosynthesis is a fundamental process used by Nature to convert solar energy into chemical energy. For the last twenty years, many solutions have been explored to provide electrical power from the photosynthetic chain. In this context, the coupling between microalgae and exogenous quinones is an encouraging strategy because of the capability of quinones to be reduced by the photosynthetic chain. The ability of a quinone to be a good or bad electron acceptor can be evaluated by fluorescence measurements. Fluorescence analyses are thus a convenient tool helping to define a diverting parameter for some quinones. However, this parameter is implicitly designed on the basis of a particular light capture mechanism by algae. In this paper, we propose to revisit previous fluorescence experimental data by considering the two possible mechanisms (lake vs. puddle) and discussing their implication on the conclusions of the analysis. In particular, we show that the maximum extraction efficiency depends on the mechanism (in the case of 2,6-dichlorobenzoquinone - 2,6-DCBQ, (0.45 ± 0.02) vs (0.61 ± 0.03) for lake and puddle mechanisms respectively) but that the trends for different quinones remain correlated to the redox potentials independently of the mechanism.
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Affiliation(s)
- Léna Beauzamy
- PASTEUR, Département de Chimie, Ecole Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France; Laboratory of Membrane and Molecular Physiology at IBPC, UMR 7141, CNRS/Sorbonne Université, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Guillaume Longatte
- PASTEUR, Département de Chimie, Ecole Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France; University of Bordeaux, Bordeaux INP, ISM, UMR CNRS 5255, Pessac 33607, France(2)
| | - Manon Guille-Collignon
- PASTEUR, Département de Chimie, Ecole Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - Frédéric Lemaître
- PASTEUR, Département de Chimie, Ecole Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France.
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2
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Ezequiel J, Nitschke MR, Laviale M, Serôdio J, Frommlet JC. Concurrent bioimaging of microalgal photophysiology and oxidative stress. PHOTOSYNTHESIS RESEARCH 2023; 155:177-190. [PMID: 36463555 DOI: 10.1007/s11120-022-00989-6] [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: 07/29/2022] [Accepted: 11/24/2022] [Indexed: 06/17/2023]
Abstract
The production of reactive oxygen species (ROS) is an unavoidable consequence of oxygenic photosynthesis and represents a major cause of oxidative stress in phototrophs, having detrimental effects on the photosynthetic apparatus, limiting cell growth, and productivity. Several methods have been developed for the quantification of cellular ROS, however, most are invasive, requiring the destruction of the sample. Here, we present a new methodology that allows the concurrent quantification of ROS and photosynthetic activity, using the fluorochrome dichlorofluorescein (DCF) and in vivo chlorophyll a fluorescence, respectively. Both types of fluorescence were measured using an imaging Pulse Amplitude Modulation (PAM) fluorometer, modified by adding a UVA-excitation light source (385 nm) and a green bandpass emission filter (530 nm) to enable the sequential capture of red chlorophyll fluorescence and green DCF fluorescence in the same sample. The method was established on Phaeodactylum tricornutum Bohlin, an important marine model diatom species, by determining protocol conditions that permitted the detection of ROS without impacting photosynthetic activity. The utility of the method was validated by quantifying the effects of two herbicides (DCMU and methyl viologen) on the photosynthetic activity and ROS production in P. tricornutum and of light acclimation state in Navicula cf. recens Lange-Bertalot, a common benthic diatom. The developed method is rapid and non-destructive, allowing for the high-throughput screening of multiple samples over time.
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Affiliation(s)
- João Ezequiel
- Department of Biology and CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal
- RAIZ - Forest and Paper Research Institute, Quinta de S. Francisco, Apartado 15, 3801-501, Eixo, Portugal
| | - Matthew R Nitschke
- Department of Biology and CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal
- School of Biological Sciences , Victoria University of Wellington, Wellington, 6012, New Zealand
| | - Martin Laviale
- Department of Biology and CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal
- Université de Lorraine, CNRS, LIEC, 57000, Metz, France
| | - João Serôdio
- Department of Biology and CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal.
| | - Jörg C Frommlet
- Department of Biology and CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal.
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3
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Kono M, Matsuzawa S, Noguchi T, Miyata K, Oguchi R, Terashima I. A new method for separate evaluation of PSII with inactive oxygen evolving complex and active D1 by the pulse-amplitude modulated chlorophyll fluorometry. FUNCTIONAL PLANT BIOLOGY : FPB 2022; 49:542-553. [PMID: 34511179 DOI: 10.1071/fp21073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 08/13/2021] [Indexed: 06/13/2023]
Abstract
A method that separately quantifies the PSII with inactive oxygen-evolving complex (OEC) and active D1 retaining the primary quinone acceptor (QA )-reducing activity from the PSII with damaged D1 in the leaf was developed using PAM fluorometry. It is necessary to fully reduce QA to obtain F m , the maximum fluorescence. However, QA in PSII with inactive OEC and active D1 would not be fully reduced by a saturating flash. We used the acceptor-side inhibitor DCMU to fully reduce QA . Leaves of cucumber (Cucumis sativus L.) were chilled at 4°C in dark or illuminated with UV-A to selectively inactivate OEC. After these treatments, F v /F m , the maximum quantum yield, in the leaves vacuum-infiltrated with DCMU were greater than those in water-infiltrated leaves. In contrast, when the leaves were illuminated by red light to photodamage D1, F v /F m did not differ between DCMU- and water-infiltrated leaves. These results indicate relevance of the present evaluation of the fraction of PSII with inactive OEC and active D1. Several examinations in the laboratory and glasshouse showed that PSII with inactive OEC and active D1 was only rarely observed. The present simple method would serve as a useful tool to clarify the details of the PSII photoinhibition.
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Affiliation(s)
- Masaru Kono
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; and Corresponding author
| | - Sae Matsuzawa
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Takaya Noguchi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kazunori Miyata
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Riichi Oguchi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Ichiro Terashima
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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4
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Competition between intra-protein charge recombination and electron transfer outside photosystem I complexes used for photovoltaic applications. Photochem Photobiol Sci 2022; 21:319-336. [PMID: 35119621 DOI: 10.1007/s43630-022-00170-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 01/07/2022] [Indexed: 02/01/2023]
Abstract
Photosystem I (PSI) complexes isolated from three different species were electrodeposited on FTO conducting glass, forming a photoactive multilayer of the photo-electrode, for investigation of intricate electron transfer (ET) properties in such green hybrid nanosystems. The internal quantum efficiency of photo-electrochemical cells (PEC) containing the PSI-based photo-electrodes did not exceed ~ 0.5%. To reveal the reason for such a low efficiency of photocurrent generation, the temporal evolution of the transient concentration of the photo-oxidized primary electron donor, P+, was studied in aqueous suspensions of the PSI complexes by time-resolved absorption spectroscopy. The results of these measurements provided the information on: (1) completeness of charge separation in PSI reaction centers (RCs), (2) dynamics of internal charge recombination, and (3) efficiency of electron transfer from PSI to the electrolyte, which is the reaction competing with the internal charge recombination in the PSI RC. The efficiency of the full charge separation in the PSI complexes used for functionalization of the electrodes was ~ 90%, indicating that incomplete charge separation was not the main reason for the small yield of photocurrents. For the PSI particles isolated from a green alga Chlamydomonas reinhardtii, the probability of ET outside PSI was ~ 30-40%, whereas for their counterparts isolated from a cyanobacterium Synechocystis sp. PCC 6803 and a red alga Cyanidioschyzon merolae, it represented a mere ~ 4%. We conclude from the transient absorption data for the PSI biocatalysts in solution that the observed small photocurrent efficiency of ~ 0.5% for all the PECs analyzed in this study is likely due to: (1) limited efficiency of ET outside PSI, particularly in the case of PECs based on PSI from Synechocystis and C. merolae, and (2) the electrolyte-mediated electric short-circuiting in PSI particles forming the photoactive layer, particularly in the case of the C. reinhardtii PEC.
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Sayegh A, Perego LA, Arderiu Romero M, Escudero L, Delacotte J, Guille‐Collignon M, Grimaud L, Bailleul B, Lemaître F. Finding Adapted Quinones for Harvesting Electrons from Photosynthetic Algae Suspensions. ChemElectroChem 2021. [DOI: 10.1002/celc.202100757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Adnan Sayegh
- PASTEUR Département de Chimie Ecole Normale Supérieure PSL University, Sorbonne Université CNRS, 75005 Paris France
| | - Luca A. Perego
- Laboratoire des biomolécules (LBM) Département de chimie Sorbonne Université École normale supérieure PSL University, Sorbonne Université CNRS, 75005 Paris France
| | - Marc Arderiu Romero
- PASTEUR Département de Chimie Ecole Normale Supérieure PSL University, Sorbonne Université CNRS, 75005 Paris France
- Laboratory of Membrane and Molecular Physiology at IBPC UMR 7141 CNRS/Sorbonne Université 13 rue Pierre et Marie Curie 75005 Paris France
| | - Louis Escudero
- PASTEUR Département de Chimie Ecole Normale Supérieure PSL University, Sorbonne Université CNRS, 75005 Paris France
| | - Jérôme Delacotte
- PASTEUR Département de Chimie Ecole Normale Supérieure PSL University, Sorbonne Université CNRS, 75005 Paris France
| | - Manon Guille‐Collignon
- PASTEUR Département de Chimie Ecole Normale Supérieure PSL University, Sorbonne Université CNRS, 75005 Paris France
| | - Laurence Grimaud
- Laboratoire des biomolécules (LBM) Département de chimie Sorbonne Université École normale supérieure PSL University, Sorbonne Université CNRS, 75005 Paris France
| | - Benjamin Bailleul
- Laboratory of Membrane and Molecular Physiology at IBPC UMR 7141 CNRS/Sorbonne Université 13 rue Pierre et Marie Curie 75005 Paris France
| | - Frédéric Lemaître
- PASTEUR Département de Chimie Ecole Normale Supérieure PSL University, Sorbonne Université CNRS, 75005 Paris France
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6
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Terashima I, Matsuo M, Suzuki Y, Yamori W, Kono M. Photosystem I in low light-grown leaves of Alocasia odora, a shade-tolerant plant, is resistant to fluctuating light-induced photoinhibition. PHOTOSYNTHESIS RESEARCH 2021; 149:69-82. [PMID: 33817762 DOI: 10.1007/s11120-021-00832-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/22/2021] [Indexed: 05/15/2023]
Abstract
When intact green leaves are exposed to the fluctuating light, in which high light (HL) and low light (LL) alternate, photosystem I (PSI) is readily damaged. This PSI inhibition is mostly alleviated by the addition of far-red (FR) light. Here, we grew Alocasia odora, a shade-tolerant species, at several light levels and examined their photosynthetic traits in relation to the fluctuating light-induced PSI inhibition. We found that, even in the absence of FR, PSI in LL-grown leaves was resistant to the fluctuating light. LL leaves showed higher chlorophyll (Chl) contents on leaf area basis, lower Chl a/b ratios, lower cytochrome f/P700 ratios, and lower PSII/PSI excitation ratios assessed by the 77 K fluorescence. Also, P700 in the HL phase of the fluctuating light was more oxidized. The results of the regression analyses of the PSI photoinhibition to these traits indicate that the lower electron flow rate to P700 and more excitation energy transfer to PSI protect PSI in LL-grown leaves. Both of these contribute oxidization of P700 to the efficient quencher form P700+. These features may be common in LL-grown shade-tolerant species, which are often exposed to strong sunflecks in their natural habitats.
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Affiliation(s)
- Ichiro Terashima
- Department of Biological Sciences, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Mitsutoshi Matsuo
- Department of Biological Sciences, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Yoshihiro Suzuki
- Department of Biological Sciences, Faculty of Science, Kanagawa University, 2946 Tsuchiya, Hiratsuka-City, Kanagawa, 259-1293, Japan
| | - Wataru Yamori
- Department of Biological Sciences, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for Sustainable Agro-ecosystem Services (ISAS), Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Midori-cho, Nishitokyo-City, Tokyo, 188-0002, Japan
| | - Masaru Kono
- Department of Biological Sciences, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
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7
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Photosynthesis-Inhibiting Activity of N-(Disubstituted-phenyl)-3-hydroxynaphthalene-2-carboxamides. Molecules 2021; 26:molecules26144336. [PMID: 34299611 PMCID: PMC8306061 DOI: 10.3390/molecules26144336] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 07/09/2021] [Accepted: 07/14/2021] [Indexed: 11/22/2022] Open
Abstract
A set of twenty-four 3-hydroxynaphthalene-2-carboxanilides, disubstituted on the anilide ring by combinations of methoxy/methyl/fluoro/chloro/bromo and ditrifluoromethyl groups at different positions, was prepared. The compounds were tested for their ability to inhibit photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. N-(3,5-Difluorophenyl)-, N-(3,5-dimethylphenyl)-, N-(2,5-difluorophenyl)- and N-(2,5-dimethylphenyl)-3-hydroxynaphthalene-2-carboxamides showed the highest PET-inhibiting activity (IC50 ~ 10 µM) within the series. These compounds were able to inhibit PET in photosystem II. It has been found that PET-inhibiting activity strongly depends on the position of the individual substituents on the anilide ring and on the lipophilicity of the compounds. The electron-withdrawing properties of the substituents contribute towards the PET activity of these compounds.
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8
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Hasegawa H, Tsurumaki T, Imamura S, Sonoike K, Tanaka K. The circadian rhythm regulator RpaA modulates photosynthetic electron transport and alters the preferable temperature range for growth in a cyanobacterium. FEBS Lett 2021; 595:1480-1492. [PMID: 33728661 DOI: 10.1002/1873-3468.14075] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 03/07/2021] [Accepted: 03/09/2021] [Indexed: 11/07/2022]
Abstract
Cyanobacterial strains can grow within a specific temperature range that approximately corresponds to their natural habitat. However, how the preferable temperature range for growth (PTRG) is determined at the molecular level remains unclear. In this study, we detected a PTRG upshift in a mutant strain of Synechococcus elongatus PCC 7942 lacking the circadian rhythm regulator RpaA. Subsequent analyses revealed that RpaA decreases the electron transport from photosystem I to NADPH. The change in electron transport likely inhibits H2 O2 generation under high-temperature conditions and contributes to the observed PTRG upshift in rpaA-deficient cells. The importance of the effects of the circadian rhythm regulator on the PTRG is discussed.
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Affiliation(s)
- Hazuki Hasegawa
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Tatsuhiro Tsurumaki
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
- School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Japan
| | - Sousuke Imamura
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
| | - Kintake Sonoike
- Faculty of Education and Integrated Arts and Sciences, Waseda University, Tokyo, Japan
| | - Kan Tanaka
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
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9
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Beauzamy L, Delacotte J, Bailleul B, Tanaka K, Nakanishi S, Wollman FA, Lemaître F. Mediator-Microorganism Interaction in Microbial Solar Cell: a Fluo-Electrochemical Insight. Anal Chem 2020; 92:7532-7539. [PMID: 32352279 DOI: 10.1021/acs.analchem.9b05808] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Microbial solar cells that mainly rely on the use of photosynthesic organisms are a promising alternative to photovoltaics for solar electricity production. In that way, we propose a new approach involving electrochemistry and fluorescence techniques. The coupled setup Electro-Pulse-Amplitude-Modulation ("e-PAM") enables the simultaneous recording of the produced photocurrent and fluorescence signals from the photosynthetic chain. This methodology was validated with a suspension of green alga Chlamydomonas reinhardtii in interaction with an exogenous redox mediator (2,6-dichlorobenzoquinone; DCBQ). The balance between photosynthetic chain events (PSII photochemical yield, quenching) and the extracted electricity can be monitored overtime. More particularly, the nonphotochemical quenching induced by DCBQ mirrors the photocurrent. This setup thus helps to distinguish the electron harvesting from some side effects due to quinones in real time. It therefore paves the way for future analyses devoted to the choice of the experimental conditions (redox mediator, photosynthetic organisms, and so on) to find the best electron extraction.
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Affiliation(s)
- Léna Beauzamy
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France.,Institut de Biologie Physico-Chimique, UMR7141 Biologie du Chloroplaste et Perception de la Lumière Chez les Micro-Algues, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Jérôme Delacotte
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - Benjamin Bailleul
- Institut de Biologie Physico-Chimique, UMR7141 Biologie du Chloroplaste et Perception de la Lumière Chez les Micro-Algues, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | | | | | - Francis-André Wollman
- Institut de Biologie Physico-Chimique, UMR7141 Biologie du Chloroplaste et Perception de la Lumière Chez les Micro-Algues, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Frédéric Lemaître
- PASTEUR, Département de Chimie, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
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10
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Szewczyk S, Białek R, Burdziński G, Gibasiewicz K. Photovoltaic activity of electrodes based on intact photosystem I electrodeposited on bare conducting glass. PHOTOSYNTHESIS RESEARCH 2020; 144:1-12. [PMID: 32078102 PMCID: PMC7113217 DOI: 10.1007/s11120-020-00722-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 02/10/2020] [Indexed: 06/10/2023]
Abstract
We demonstrate photovoltaic activity of electrodes composed of fluorine-doped tin oxide (FTO) conducting glass and a multilayer of trimeric photosystem I (PSI) from cyanobacterium Synechocystis sp. PCC 6803 yielding, at open circuit potential (OCP) of + 100 mV (vs. SHE), internal quantum efficiency of (0.37 ± 0.11)% and photocurrent density of up to (0.5 ± 0.1) µA/cm2. The photocurrent measured for OCP is of cathodic nature meaning that preferentially the electrons are injected from the conducting layer of the FTO glass to the photooxidized PSI primary electron donor, P700+, and further transferred from the photoreduced final electron acceptor of PSI, Fb-, via ascorbate electrolyte to the counter electrode. This observation is consistent with preferential donor-side orientation of PSI on FTO imposed by applied electrodeposition. However, by applying high-positive bias (+ 620 mV) to the PSI-FTO electrode, exceeding redox midpoint potential of P700 (+ 450 mV), the photocurrent reverses its orientation and becomes anodic. This is explained by "switching off" the natural photoactivity of PSI particles (by the electrochemical oxidation of P700 to P700+) and "switching on" the anodic photocurrent from PSI antenna Chls prone to photooxidation at high potentials. The efficient control of the P700 redox state (P700 or P700+) by external bias applied to the PSI-FTO electrodes was evidenced by ultrafast transient absorption spectroscopy. The advantage of the presented system is its structural simplicity together with in situ-proven high intactness of the PSI particles.
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Affiliation(s)
- Sebastian Szewczyk
- Faculty of Physics, Adam Mickiewicz University in Poznań, ul. Uniwersytetu Poznańskiego 2, 61-614, Poznań, Poland
| | - Rafał Białek
- Faculty of Physics, Adam Mickiewicz University in Poznań, ul. Uniwersytetu Poznańskiego 2, 61-614, Poznań, Poland
| | - Gotard Burdziński
- Faculty of Physics, Adam Mickiewicz University in Poznań, ul. Uniwersytetu Poznańskiego 2, 61-614, Poznań, Poland
| | - Krzysztof Gibasiewicz
- Faculty of Physics, Adam Mickiewicz University in Poznań, ul. Uniwersytetu Poznańskiego 2, 61-614, Poznań, Poland.
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11
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Bak A, Pizova H, Kozik V, Vorcakova K, Kos J, Treml J, Odehnalova K, Oravec M, Imramovsky A, Bobal P, Smolinski A, Trávníček Z, Jampilek J. SAR-mediated Similarity Assessment of the Property Profile for New, Silicon-Based AChE/BChE Inhibitors. Int J Mol Sci 2019; 20:E5385. [PMID: 31671776 PMCID: PMC6862691 DOI: 10.3390/ijms20215385] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 10/25/2019] [Accepted: 10/27/2019] [Indexed: 12/20/2022] Open
Abstract
A set of 25 novel, silicon-based carbamate derivatives as potential acetyl- and butyrylcholinesterase (AChE/BChE) inhibitors was synthesized and characterized by their in vitro inhibition profiles and the selectivity indexes (SIs). The prepared compounds were also tested for their inhibition potential on photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. In fact, some of the newly prepared molecules revealed comparable or even better inhibitory activities compared to the marketed drugs (rivastigmine or galanthamine) and commercially applied pesticide Diuron®, respectively. Generally, most compounds exhibited better inhibition potency towards AChE; however, a wider activity span was observed for BChE. Notably, benzyl N-[(1S)-2-[(tert-butyldimethylsilyl)oxy]-1-[(2-hydroxyphenyl)carbamoyl]ethyl]-carbamate (2) and benzyl N-[(1S)-2-[(tert-butyldimethylsilyl)oxy]-1-[(3-hydroxyphenyl)carbamoyl]ethyl]-carbamate (3) were characterized by fairly high selective indexes. Specifically, compound 2 was prescribed with the lowest IC50 value that corresponds quite well with galanthamine inhibition activity, while the inhibitory profiles of molecules 3 and benzyl-N-[(1S)-2-[(tert-butyldimethylsilyl)oxy]-1-[(4-hydroxyphenyl)carbamoyl]ethyl]carbamate (4) are in line with rivastigmine activity. Moreover, a structure-activity relationship (SAR)-driven similarity evaluation of the physicochemical properties for the carbamates examined appeared to have foreseen the activity cliffs using a similarity-activity landscape index for BChE inhibitory response values. The 'indirect' ligand-based and 'direct' protein-mediated in silico approaches were applied to specify electronic/steric/lipophilic factors that are potentially valid for quantitative (Q)SAR modeling of the carbamate analogues. The stochastic model validation was used to generate an 'average' 3D-QSAR pharmacophore pattern. Finally, the target-oriented molecular docking was employed to (re)arrange the spatial distribution of the ligand property space for BChE and photosystem II (PSII).
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Affiliation(s)
- Andrzej Bak
- Institute of Chemistry, University of Silesia, Szkolna 9, 40 007 Katowice, Poland.
| | - Hana Pizova
- Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Palackeho 1, 612 42 Brno, Czech Republic.
| | - Violetta Kozik
- Institute of Chemistry, University of Silesia, Szkolna 9, 40 007 Katowice, Poland.
| | - Katarina Vorcakova
- Department of Biological and Biochemical Sciences, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice, Czech Republic.
| | - Jiri Kos
- Division of Biologically Active Complexes and Molecular Magnets, Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University, Slechtitelu 27, 783 71 Olomouc, Czech Republic, (J.K.).
| | - Jakub Treml
- Department of Molecular Biology and Pharmaceutical Biotechnology, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Palackeho 1, 612 42 Brno, Czech Republic.
| | - Klara Odehnalova
- Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Palackeho 1, 612 42 Brno, Czech Republic.
| | - Michal Oravec
- Global Change Research Institute CAS, Belidla 986/4a, 60300 Brno, Czech Republic.
| | - Ales Imramovsky
- Institute of Organic Chemistry and Technology, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice, Czech Republic.
| | - Pavel Bobal
- Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Palackeho 1, 612 42 Brno, Czech Republic.
| | - Adam Smolinski
- Department of Energy Saving and Air Protection, Central Mining Institute, Plac Gwarkow 1, 40 166 Katowice, Poland.
| | - Zdeněk Trávníček
- Division of Biologically Active Complexes and Molecular Magnets, Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University, Slechtitelu 27, 783 71 Olomouc, Czech Republic, (J.K.).
| | - Josef Jampilek
- Division of Biologically Active Complexes and Molecular Magnets, Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University, Slechtitelu 27, 783 71 Olomouc, Czech Republic, (J.K.).
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12
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López‐Martínez M, López‐Ortiz M, Antinori ME, Wientjes E, Nin‐Hill A, Rovira C, Croce R, Díez‐Pérez I, Gorostiza P. Electrochemically Gated Long‐Distance Charge Transport in Photosystem I. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201904374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Montse López‐Martínez
- Department of Material Science and Physical ChemistryUniversity of Barcelona Martí i Franquès, 1 08028 Barcelona Spain
- Institute for Bioengineering of Catalonia (IBEC)The Barcelona Institute of Science and Technology Baldiri Reixac 10–12 08028 Barcelona Spain
- Network Biomedical Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN) 28029 Madrid Spain
- Present address: Institut für Angewandte PhysikTU Wien Vienna Austria
| | - Manuel López‐Ortiz
- Institute for Bioengineering of Catalonia (IBEC)The Barcelona Institute of Science and Technology Baldiri Reixac 10–12 08028 Barcelona Spain
- Network Biomedical Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN) 28029 Madrid Spain
| | - Maria Elena Antinori
- Institute for Bioengineering of Catalonia (IBEC)The Barcelona Institute of Science and Technology Baldiri Reixac 10–12 08028 Barcelona Spain
- Present address: Smart Materials, NanophysicsIstituto Italiano di Tecnologia Genova Italy
| | - Emilie Wientjes
- Laboratory of BiophysicsWageningen University 6700 ET Wageningen The Netherlands
| | - Alba Nin‐Hill
- Inorganic and Organic Chemistry Department & Institute of Theoretical and Computational Chemistry (IQTCUB)University of Barcelona (UB) Martí i Franquès, 1 Barcelona 08028 Spain
| | - Carme Rovira
- Inorganic and Organic Chemistry Department & Institute of Theoretical and Computational Chemistry (IQTCUB)University of Barcelona (UB) Martí i Franquès, 1 Barcelona 08028 Spain
- Catalan Institution for Research and Advanced Studies (ICREA) 08010 Barcelona Spain
| | - Roberta Croce
- Biophysics of Photosynthesis. Dep. Physics and AstronomyFaculty of SciencesVrije Universiteit Amsterdam De Boelelaan 1081 1081 HV Amsterdam The Netherlands
| | - Ismael Díez‐Pérez
- Department of Material Science and Physical ChemistryUniversity of Barcelona Martí i Franquès, 1 08028 Barcelona Spain
- Present address: Department of Chemistry, Faculty of Natural & Mathematical SciencesKing's College London London UK
| | - Pau Gorostiza
- Institute for Bioengineering of Catalonia (IBEC)The Barcelona Institute of Science and Technology Baldiri Reixac 10–12 08028 Barcelona Spain
- Network Biomedical Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN) 28029 Madrid Spain
- Catalan Institution for Research and Advanced Studies (ICREA) 08010 Barcelona Spain
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13
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López-Martínez M, López-Ortiz M, Antinori ME, Wientjes E, Nin-Hill A, Rovira C, Croce R, Díez-Pérez I, Gorostiza P. Electrochemically Gated Long-Distance Charge Transport in Photosystem I. Angew Chem Int Ed Engl 2019; 58:13280-13284. [PMID: 31310425 DOI: 10.1002/anie.201904374] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 06/23/2019] [Indexed: 12/26/2022]
Abstract
The transport of electrons along photosynthetic and respiratory chains involves a series of enzymatic reactions that are coupled through redox mediators, including proteins and small molecules. The use of native and synthetic redox probes is key to understanding charge transport mechanisms and to the design of bioelectronic sensors and solar energy conversion devices. However, redox probes have limited tunability to exchange charge at the desired electrochemical potentials (energy levels) and at different protein sites. Herein, we take advantage of electrochemical scanning tunneling microscopy (ECSTM) to control the Fermi level and nanometric position of the ECSTM probe in order to study electron transport in individual photosystem I (PSI) complexes. Current-distance measurements at different potentiostatic conditions indicate that PSI supports long-distance transport that is electrochemically gated near the redox potential of P700, with current extending farther under hole injection conditions.
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Affiliation(s)
- Montse López-Martínez
- Department of Material Science and Physical Chemistry, University of Barcelona, Martí i Franquès, 1, 08028, Barcelona, Spain.,Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain.,Network Biomedical Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 28029, Madrid, Spain.,Present address: Institut für Angewandte Physik, TU Wien, Vienna, Austria
| | - Manuel López-Ortiz
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain.,Network Biomedical Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 28029, Madrid, Spain
| | - Maria Elena Antinori
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain.,Present address: Smart Materials, Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Emilie Wientjes
- Laboratory of Biophysics, Wageningen University, 6700 ET, Wageningen, The Netherlands
| | - Alba Nin-Hill
- Inorganic and Organic Chemistry Department & Institute of Theoretical and Computational Chemistry (IQTCUB), University of Barcelona (UB), Martí i Franquès, 1, Barcelona, 08028, Spain
| | - Carme Rovira
- Inorganic and Organic Chemistry Department & Institute of Theoretical and Computational Chemistry (IQTCUB), University of Barcelona (UB), Martí i Franquès, 1, Barcelona, 08028, Spain.,Catalan Institution for Research and Advanced Studies (ICREA), 08010, Barcelona, Spain
| | - Roberta Croce
- Biophysics of Photosynthesis. Dep. Physics and Astronomy, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands
| | - Ismael Díez-Pérez
- Department of Material Science and Physical Chemistry, University of Barcelona, Martí i Franquès, 1, 08028, Barcelona, Spain.,Present address: Department of Chemistry, Faculty of Natural & Mathematical Sciences, King's College London, London, UK
| | - Pau Gorostiza
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028, Barcelona, Spain.,Network Biomedical Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 28029, Madrid, Spain.,Catalan Institution for Research and Advanced Studies (ICREA), 08010, Barcelona, Spain
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14
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Gilbert M, Bährs H, Steinberg CEW, Wilhelm C. The artificial humic substance HS1500 does not inhibit photosynthesis of the green alga Desmodesmus armatus in vivo but interacts with the photosynthetic apparatus of isolated spinach thylakoids in vitro. PHOTOSYNTHESIS RESEARCH 2018; 137:403-420. [PMID: 29777430 DOI: 10.1007/s11120-018-0513-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 05/01/2018] [Indexed: 06/08/2023]
Abstract
Humic substances (HSs) can influence the growth and composition of freshwater phytoplankton assemblage. Since HSs contain many phenolic and quinonic moieties and cause growth reductions in eco-physiological field experiments, HSs are considered photosystem II herbicides. To test this specific mode of action in vivo and in vitro, respectively, we used intact cells of the green alga Desmodesmus armatus, as well as thylakoids isolated from spinach (Spinacia oleracea) as a model system for the green algal chloroplast. Photosynthetic electron transport was measured as oxygen evolution and variable chlorophyll fluorescence. The in vivo effect of the artificial humic substance HS1500 on algae consisted of no impact on photosynthesis-irradiance curves of intact green algae compared to untreated controls. In contrast, addition of HS1500 to isolated thylakoids resulted in light-induced oxygen consumption (Mehler reaction) as an in vitro effect. Fluorescence induction kinetics of HS-treated thylakoids revealed a large static quenching effect of HS1500, but no inhibitory effect on electron transport. For the case of intact algal cells, we conclude that the highly hydrophilic and rather large molecules of HS1500 are not taken up in effective quantities and, therefore, cannot interfere with photosynthesis. The in vitro tests show that HS1500 has no inhibitory effect on photosystem II but operates as a weak, oxygen-consuming Hill acceptor at photosystem I. Hence, the results indicate that eco-physiological field experiments should focus more strongly on effects of HSs on extracellular features, such as reducing and red-shifting the underwater light field or influencing nutrient availability by cation exchange within the plankton network.
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Affiliation(s)
- Matthias Gilbert
- Institute of Biology, Department of Plant Physiology, University of Leipzig, Johannisallee 21-23, 04103, Leipzig, Germany.
| | - Hanno Bährs
- Aquacopa GmbH, Koppelbergstr. 4, 17166, Teterow, Germany
| | - Christian E W Steinberg
- Department of Biology, Freshwater and Stress Ecology, Humboldt-University Berlin, Arboretum, Späthstraße 80/81, 12437, Berlin, Germany
| | - Christian Wilhelm
- Institute of Biology, Department of Plant Physiology, University of Leipzig, Johannisallee 21-23, 04103, Leipzig, Germany.
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15
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Synthesis and Spectrum of Biological Activities of Novel N-arylcinnamamides. Int J Mol Sci 2018; 19:ijms19082318. [PMID: 30087309 PMCID: PMC6121455 DOI: 10.3390/ijms19082318] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 08/01/2018] [Accepted: 08/03/2018] [Indexed: 01/17/2023] Open
Abstract
A series of sixteen ring-substituted N-arylcinnamamides was prepared and characterized. Primary in vitro screening of all the synthesized compounds was performed against Staphylococcus aureus, three methicillin-resistant S. aureus strains, Mycobacterium tuberculosis H37Ra, Fusarium avenaceum, and Bipolaris sorokiniana. Several of the tested compounds showed antistaphylococcal, antitubercular, and antifungal activities comparable with or higher than those of ampicillin, isoniazid, and benomyl. (2E)-N-[3,5-bis(trifluoromethyl)phenyl]-3-phenylprop-2-enamide and (2E)-3-phenyl-N-[3-(trifluoromethyl)phenyl]prop-2-enamide showed the highest activities (MICs = 22.27 and 27.47 µM, respectively) against all four staphylococcal strains and against M. tuberculosis. These compounds showed an activity against biofilm formation of S. aureus ATCC 29213 in concentrations close to MICs and an ability to increase the activity of clinically used antibiotics with different mechanisms of action (vancomycin, ciprofloxacin, and tetracycline). In time-kill studies, a decrease of CFU/mL of >99% after 8 h from the beginning of incubation was observed. (2E)-N-(3,5-Dichlorophenyl)- and (2E)-N-(3,4-dichlorophenyl)-3-phenylprop-2-enamide had a MIC = 27.38 µM against M. tuberculosis, while a significant decrease (22.65%) of mycobacterial cell metabolism determined by the MTT assay was observed for the 3,5-dichlorophenyl derivative. (2E)-N-(3-Fluorophenyl)- and (2E)-N-(3-methylphenyl)-3-phenylprop-2-enamide exhibited MICs = 16.58 and 33.71 µM, respectively, against B. sorokiniana. The screening of the cytotoxicity of the most effective antimicrobial compounds was performed using THP-1 cells, and these chosen compounds did not shown any significant lethal effect. The compounds were also evaluated for their activity related to the inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. (2E)-N-(3,5-dichlorophenyl)-3-phenylprop-2-enamide (IC50 = 5.1 µM) was the most active PET inhibitor. Compounds with fungicide potency did not show any in vivo toxicity against Nicotiana tabacum var. Samsun. The structure–activity relationships are discussed.
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16
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Otsubo M, Ikoma C, Ueda M, Ishii Y, Tamura N. Functional Role of Fibrillin5 in Acclimation to Photooxidative Stress. PLANT & CELL PHYSIOLOGY 2018; 59:1670-1682. [PMID: 29741733 DOI: 10.1093/pcp/pcy093] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/02/2018] [Indexed: 05/13/2023]
Abstract
The functional role of a lipid-associated soluble protein, fibrillin5 (FBN5), was determined with the Arabidopsis thaliana homozygous fbn5-knockout mutant line (SALK_064597) that carries a T-DNA insertion within the FBN5 gene. The fbn5 mutant remained alive, displaying a slow growth and a severe dwarf phenotype. The mutant grown even under growth light conditions at 80 µmol m-2 s-1 showed a drastic decrease in electron transfer activities around PSII, with little change in electron transfer activities around PSI, a phenomenon which was exaggerated under high light stress. The accumulation of plastoquinone-9 (PQ-9) was suppressed in the mutant, and >90% of the PQ-9 pool was reduced under growth light conditions. Non-photochemical quenching (NPQ) in the mutant functioned less efficiently, resulting from little contribution by energy-dependent quenching (qE). The ultrastructure of thylakoids in the mutant revealed that their grana were unstacked and transformed into loose and disordered structures. Light-harvesting complex (LHC)-containing large photosystem complexes and photosystem core complexes in the mutant were less abundant than those in wild-type plants. These results suggest that the lack of FBN5 causes a decrease in PQ-9 and imbalance of the redox state of PQ-9, resulting in misconducting both short-term and long-term control of the input of light energy to photosynthetic reaction centers. Furthermore, in the fbn5 mutant, the expression of genes involved in jasmonic acid biosynthesis was suppressed to ≤10% of that in the wild type under both growth-light and high-light conditions, suggesting that FBN5 functions as a transmitter of 1O2 in the stroma.
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Affiliation(s)
- Mayuko Otsubo
- Department of Environmental Science, Fukuoka Women's University, Kasumigaoka 1-1-1, Higashi-ku, Fukuoka, Japan
| | - Chikako Ikoma
- Department of Environmental Science, Fukuoka Women's University, Kasumigaoka 1-1-1, Higashi-ku, Fukuoka, Japan
| | - Mariko Ueda
- Department of Environmental Science, Fukuoka Women's University, Kasumigaoka 1-1-1, Higashi-ku, Fukuoka, Japan
| | - Yumi Ishii
- Department of Environmental Science, Fukuoka Women's University, Kasumigaoka 1-1-1, Higashi-ku, Fukuoka, Japan
| | - Noriaki Tamura
- Department of Environmental Science, Fukuoka Women's University, Kasumigaoka 1-1-1, Higashi-ku, Fukuoka, Japan
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17
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Nagy V, Vidal-Meireles A, Podmaniczki A, Szentmihályi K, Rákhely G, Zsigmond L, Kovács L, Tóth SZ. The mechanism of photosystem-II inactivation during sulphur deprivation-induced H 2 production in Chlamydomonas reinhardtii. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 94:548-561. [PMID: 29474754 DOI: 10.1111/tpj.13878] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 01/29/2018] [Accepted: 02/05/2018] [Indexed: 05/11/2023]
Abstract
Sulphur limitation may restrain cell growth and viability. In the green alga Chlamydomonas reinhardtii, sulphur limitation may induce H2 production lasting for several days, which can be exploited as a renewable energy source. Sulphur limitation causes a large number of physiological changes, including the inactivation of photosystem II (PSII), leading to the establishment of hypoxia, essential for the increase in hydrogenase expression and activity. The inactivation of PSII has long been assumed to be caused by the sulphur-limited turnover of its reaction center protein PsbA. Here we reinvestigated this issue in detail and show that: (i) upon transferring Chlamydomonas cells to sulphur-free media, the cellular sulphur content decreases only by about 25%; (ii) as demonstrated by lincomycin treatments, PsbA has a significant turnover, and other photosynthetic subunits, namely RbcL and CP43, are degraded more rapidly than PsbA. On the other hand, sulphur limitation imposes oxidative stress early on, most probably involving the formation of singlet oxygen in PSII, which leads to an increase in the expression of GDP-L-galactose phosphorylase, playing an essential role in ascorbate biosynthesis. When accumulated to the millimolar concentration range, ascorbate may inactivate the oxygen-evolving complex and provide electrons to PSII, albeit at a low rate. In the absence of a functional donor side and sufficient electron transport, PSII reaction centers are inactivated and degraded. We therefore demonstrate that the inactivation of PSII is a complex and multistep process, which may serve to mitigate the damaging effects of sulphur limitation.
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Affiliation(s)
- Valéria Nagy
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - André Vidal-Meireles
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Anna Podmaniczki
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Klára Szentmihályi
- Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences Hungarian Academy of Sciences, Budapest, Hungary
| | - Gábor Rákhely
- Department of Biotechnology, University of Szeged, Szeged, Hungary
| | - Laura Zsigmond
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - László Kovács
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Szilvia Z Tóth
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
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18
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Gonec T, Kos J, Pesko M, Dohanosova J, Oravec M, Liptaj T, Kralova K, Jampilek J. Halogenated 1-Hydroxynaphthalene-2-Carboxanilides Affecting Photosynthetic Electron Transport in Photosystem II. Molecules 2017; 22:molecules22101709. [PMID: 29023407 PMCID: PMC6151762 DOI: 10.3390/molecules22101709] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 10/09/2017] [Indexed: 12/29/2022] Open
Abstract
Series of seventeen new multihalogenated 1-hydroxynaphthalene-2-carboxanilides was prepared and characterized. All the compounds were tested for their activity related to the inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. 1-Hydroxy-N-phenylnaphthalene-2-carboxamides substituted in the anilide part by 3,5-dichloro-, 4-bromo-3-chloro-, 2,5-dibromo- and 3,4,5-trichloro atoms were the most potent PET inhibitors (IC50 = 5.2, 6.7, 7.6 and 8.0 µM, respectively). The inhibitory activity of these compounds depends on the position and the type of halogen substituents, i.e., on lipophilicity and electronic properties of individual substituents of the anilide part of the molecule. Interactions of the studied compounds with chlorophyll a and aromatic amino acids present in pigment-protein complexes mainly in PS II were documented by fluorescence spectroscopy. The section between P680 and plastoquinone QB in the PET chain occurring on the acceptor side of PS II can be suggested as the site of action of the compounds. The structure-activity relationships are discussed.
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Affiliation(s)
- Tomas Gonec
- Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Palackeho 1, Brno 61242, Czech Republic.
| | - Jiri Kos
- Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Palackeho 1, Brno 61242, Czech Republic.
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University, Odbojarov 10, Bratislava 83232, Slovakia.
| | - Matus Pesko
- Department of Environmental Ecology, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, Bratislava 84215, Slovakia.
| | - Jana Dohanosova
- Central Laboratories, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinskeho 9, Bratislava 81237, Slovakia.
| | - Michal Oravec
- Global Change Research Institute CAS, Belidla 986/4a, 60300 Brno, Czech Republic.
| | - Tibor Liptaj
- Central Laboratories, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinskeho 9, Bratislava 81237, Slovakia.
| | - Katarina Kralova
- Institute of Chemistry, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, Bratislava 84215, Slovakia.
| | - Josef Jampilek
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University, Odbojarov 10, Bratislava 83232, Slovakia.
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19
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Gonec T, Stranik J, Pesko M, Kos J, Oravec M, Kralova K, Jampilek J. Photosynthesis-Inhibiting Activity of 1-[(2-Chlorophenyl)carbamoyl]- and 1-[(2-Nitrophenyl)carbamoyl]naphthalen-2-yl Alkylcarbamates. Molecules 2017; 22:molecules22071199. [PMID: 28714937 PMCID: PMC6152350 DOI: 10.3390/molecules22071199] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 07/11/2017] [Accepted: 07/14/2017] [Indexed: 01/07/2023] Open
Abstract
Eight 1-[(2-chlorophenyl)carbamoyl]naphthalen-2-yl alkylcarbamates and eight 1-[(2-nitrophenyl)carbamoyl]naphthalen-2-yl alkylcarbamates were tested for their activity related to the inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. The PET-inhibiting activity of the compounds was relatively low; the corresponding IC50 values ranged from 0.05 to 0.664 mmol/L; and the highest activity within the series of compounds was observed for 1-[(2-chlorophenyl)-carbamoyl]naphthalen-2-yl propylcarbamate. It has been proven that the compounds are PET-inhibitors in photosystem II. Despite rather low PET-inhibiting activities, primary structure-activity trends can be discussed.
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Affiliation(s)
- Tomas Gonec
- Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Palackeho 1, 61242 Brno, Czech Republic.
| | - Josef Stranik
- Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Palackeho 1, 61242 Brno, Czech Republic.
| | - Matus Pesko
- Department of Environmental Ecology, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, 84215 Bratislava, Slovakia.
| | - Jiri Kos
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University, Odbojarov 10, 83232 Bratislava, Slovakia.
| | - Michal Oravec
- Global Change Research Institute CAS, Belidla 986/4a, 60300 Brno, Czech Republic.
| | - Katarina Kralova
- Institute of Chemistry, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, 84215 Bratislava, Slovakia.
| | - Josef Jampilek
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University, Odbojarov 10, 83232 Bratislava, Slovakia.
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20
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Gonec T, Kralova K, Pesko M, Jampilek J. Antimycobacterial N-alkoxyphenylhydroxynaphthalenecarboxamides affecting photosystem II. Bioorg Med Chem Lett 2017; 27:1881-1885. [PMID: 28363749 DOI: 10.1016/j.bmcl.2017.03.050] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 03/16/2017] [Accepted: 03/20/2017] [Indexed: 12/14/2022]
Abstract
N-(Alkoxyphenyl)-2-hydroxynaphthalene-1-carboxamides (series A) and N-(alkoxyphenyl)-1-hydroxynaphthalene-2-carboxamides (series B) affecting photosystem (PS) II inhibited photosynthetic electron transport (PET) in spinach chloroplasts. Their inhibitory activity depended on the compound lipophilicity as well as on the position of the alkoxy substituent. The most potent PET inhibitors were 2-hydroxy-N-phenylnaphthalene-1-carboxamide and N-[3-(but-2-yloxy)phenyl]-2-hydroxynaphthalene-1-carboxamide within series A (IC50=28.9 and 42.5µM, respectively) and 1-hydroxy-N-(3-propoxyphenyl)naphthalene-2-carboxamide and 1-hydroxy-N-(3-ethoxyphenyl)-naphthalene-2-carboxamide (IC50=2.0 and 3.1µM, respectively) within series B. The inhibitory activity of C'(3) or C'(4) alkoxy substituted compounds of series B was considerably higher than that of C'(2) ones within series A. The PET-inhibiting activities of both series were compared with the PET inhibition of isomeric N-alkoxyphenyl-3-hydroxynaphthalene-2-carboxamides (series C) reported recently. Interactions of the studied compounds with chlorophyll a and aromatic amino acids present in pigment-protein complexes mainly in PS II were documented by fluorescence spectroscopy. The section between P680 and plastoquinone QB in the PET chain occurring on the acceptor side of PSII can be suggested as the site of action of the compounds.
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Affiliation(s)
- Tomas Gonec
- Department of Chemical Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences, Palackeho 1, 612 42 Brno, Czech Republic.
| | - Katarina Kralova
- Institute of Chemistry, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, 842 15 Bratislava, Slovakia
| | - Matus Pesko
- Department of Environmental Ecology, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, 842 15 Bratislava, Slovakia
| | - Josef Jampilek
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Comenius University, Odbojarov 10, 832 32 Bratislava, Slovakia.
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21
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Miyachi M, Ikehira S, Nishiori D, Yamanoi Y, Yamada M, Iwai M, Tomo T, Allakhverdiev SI, Nishihara H. Photocurrent Generation of Reconstituted Photosystem II on a Self-Assembled Gold Film. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:1351-1358. [PMID: 28103045 DOI: 10.1021/acs.langmuir.6b03499] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Photosystem II (PSII)-modified gold electrodes were prepared by the deposition of PSII reconstituted with platinum nanoparticles (PtNPs) on Au electrodes. PtNPs modified with 1-[15-(3,5,6-trimethyl-1,4-benzoquinone-2-yl)]pentadecyl disulfide ((TMQ(CH2)15S)2) were incorporated into the QB site of PSII isolated from thermophilic cyanobacterium Thermosynechococcus elongatus. The reconstitution was confirmed by QA-reoxidation measurements. PSII reconstituted with PtNPs was deposited and integrated on a Au(111) surface modified with 4,4'-biphenyldithiol. The cross section of the reconstituted PSII film on the Au electrode was investigated by SEM. Absorption spectra showed that the surface coverage of the electrode was about 18 pmol PSII cm-2. A photocurrent density of 15 nAcm-2 at E = +0.10 V (vs Ag/AgCl) was observed under 680 nm irradiation. The photoresponse showed good reversibility under alternating light and dark conditions. Clear photoresponses were not observed in the absence of PSII and molecular wire. These results supported the photocurrent originated from PSII and moved to a gold electrode by light irradiation, which also confirmed conjugation with orientation through the molecular wire.
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Affiliation(s)
- Mariko Miyachi
- Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Shu Ikehira
- Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Daiki Nishiori
- Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yoshinori Yamanoi
- Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Masato Yamada
- Department of Biology, Faculty of Science, Tokyo University of Science , Kagurazaka 1-3, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Masako Iwai
- Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology , Yokohama 226-8503, Japan
| | - Tatsuya Tomo
- Department of Biology, Faculty of Science, Tokyo University of Science , Kagurazaka 1-3, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Suleyman I Allakhverdiev
- Controlled Photobiosynthesis Laboratory, Institute of Plant Physiology, Russian Academy of Sciences , Botanicheskaya Street 35, Moscow 127276, Russia
- Institute of Basic Biological Problems, Russian Academy of Sciences , Pushchino, Moscow Region 142290, Russia
- Faculty of Biology, M. V. Lomonosov Moscow State University , Leninskie Gory 1-12, Moscow 119991, Russia
| | - Hiroshi Nishihara
- Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Thagela P, Yadav RK, Mishra V, Dahuja A, Ahmad A, Singh PK, Tiwari BS, Abraham G. Salinity-induced inhibition of growth in the aquatic pteridophyte Azolla microphylla primarily involves inhibition of photosynthetic components and signaling molecules as revealed by proteome analysis. PROTOPLASMA 2017; 254:303-313. [PMID: 26837223 DOI: 10.1007/s00709-016-0946-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 01/18/2016] [Indexed: 05/21/2023]
Abstract
Salinity stress causes adverse physiological and biochemical changes in the growth and productivity of a plant. Azolla, a symbiotic pteridophyte and potent candidate for biofertilizer due to its nitrogen fixation ability, shows reduced growth and nitrogen fixation during saline stress. To better understand regulatory components involved in salinity-induced physiological changes, in the present study, Azolla microphylla plants were exposed to NaCl (6.74 and 8.61 ds/m) and growth, photochemical reactions of photosynthesis, ion accumulation, and changes in cellular proteome were studied. Maximum dry weight was accumulated in control and untreated plant while a substantial decrease in dry weight was observed in the plants exposed to salinity. Exposure of the organism to different concentrations of salt in hydroponic conditions resulted in differential level of Na+ and K+ ion accumulation. Comparative analysis of salinity-induced proteome changes in A. microphylla revealed 58 salt responsive proteins which were differentially expressed during the salt exposure. Moreover, 42 % spots among differentially expressed proteins were involved in different signaling events. The identified proteins are involved in photosynthesis, energy metabolism, amino acid biosynthesis, protein synthesis, and defense. Downregulation of these key metabolic proteins appears to inhibit the growth of A. microphylla in response to salinity. Altogether, the study revealed that in Azolla, increased salinity primarily affected signaling and photosynthesis that in turn leads to reduced biomass.
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Affiliation(s)
- Preeti Thagela
- Centre for Conservation and Utilization of BGA, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Ravindra Kumar Yadav
- Centre for Conservation and Utilization of BGA, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Vagish Mishra
- NRCPB, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi, 110012, India
| | - Anil Dahuja
- Division of Biochemistry, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Altaf Ahmad
- Department of Botany, Aligarh Muslim University, Aligarh, U.P., India
| | - Pawan Kumar Singh
- Department of Botany, Banaras Hindu University, Varanasi, 221005, U.P., India
| | - Budhi Sagar Tiwari
- School of Biological Sciences and Biotechnology, University and Institute of Advanced Research, Gandhinagar, 382007, Gujrat, India
| | - Gerard Abraham
- Centre for Conservation and Utilization of BGA, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
- Centre for Conservation and Utilization of BGA, CCUBGA, NEAR AUDITORIUM, New Delhi, 110012, India.
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23
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Kasuno M, Kimura H, Yasutomo H, Torimura M, Murakami D, Tsukatani Y, Hanada S, Matsushita T, Tao H. An Evaluation of Sensor Performance for Harmful Compounds by Using Photo-Induced Electron Transfer from Photosynthetic Membranes to Electrodes. SENSORS 2016; 16:438. [PMID: 27023553 PMCID: PMC4850952 DOI: 10.3390/s16040438] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 03/18/2016] [Accepted: 03/22/2016] [Indexed: 11/16/2022]
Abstract
Rapid, simple, and low-cost screening procedures are necessary for the detection of harmful compounds in the effluent that flows out of point sources such as industrial outfall. The present study investigated the effects on a novel sensor of harmful compounds such as KCN, phenol, and herbicides such as 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine (atrazine), and 2-N-tert-butyl-4-N-ethyl-6-methylsulfanyl-1,3,5-triazine-2,4-diamine (terbutryn). The sensor employed an electrode system that incorporated the photocurrent of intra-cytoplasmic membranes (so-called chromatophores) prepared from photosynthetic bacteria and linked using carbon paste electrodes. The amperometric curve (photocurrent-time curve) of photo-induced electron transfer from chromatophores of the purple photosynthetic bacterium Rhodobacter sphaeroides to the electrode via an exogenous electron acceptor was composed of two characteristic phases: an abrupt increase in current immediately after illumination (I₀), and constant current over time (Ic). Compared with other redox compounds, 2,5-dichloro-1,4-benzoquinone (DCBQ) was the most useful exogenous electron acceptor in this system. Photo-reduction of DCBQ exhibited Michaelis-Menten-like kinetics, and reduction rates were dependent on the amount of DCBQ and the photon flux intensity. The Ic decreased in the presence of KCN at concentrations over 0.05 μM (=μmol·dm(-3)). The I₀ decreased following the addition of phenol at concentrations over 20 μM. The Ic was affected by terbutryn at concentrations over 10 μM. In contrast, DCMU and atrazine had no effect on either I₀ or Ic. The utility of this electrode system for the detection of harmful compounds is discussed.
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Affiliation(s)
- Megumi Kasuno
- Department of Materials Chemistry, Faculty of Science and Technology, Ryukoku University, Otsu, Shiga 520-2194, Japan.
| | - Hiroki Kimura
- Department of Materials Chemistry, Faculty of Science and Technology, Ryukoku University, Otsu, Shiga 520-2194, Japan.
| | - Hisataka Yasutomo
- Department of Materials Chemistry, Faculty of Science and Technology, Ryukoku University, Otsu, Shiga 520-2194, Japan.
| | - Masaki Torimura
- Research Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8569, Japan.
| | - Daisuke Murakami
- Research Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8569, Japan.
| | - Yusuke Tsukatani
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo 152-8550, Japan.
| | - Satoshi Hanada
- Institute for Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8566, Japan.
| | - Takayuki Matsushita
- Department of Materials Chemistry, Faculty of Science and Technology, Ryukoku University, Otsu, Shiga 520-2194, Japan.
| | - Hiroaki Tao
- Research Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8569, Japan.
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24
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Gordiichuk PI, Rimmerman D, Paul A, Gautier DA, Gruszka A, Saller M, de Vries JW, Wetzelaer GJAH, Manca M, Gomulya W, Matmor M, Gloukhikh E, Loznik M, Ashkenasy N, Blom PWM, Rögner M, Loi MA, Richter S, Herrmann A. Filling the Green Gap of a Megadalton Photosystem I Complex by Conjugation of Organic Dyes. Bioconjug Chem 2015; 27:36-41. [DOI: 10.1021/acs.bioconjchem.5b00583] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Dolev Rimmerman
- The
Bio and Molecular Electronics Group, Department of Materials Science
and Engineering, Faculty of Engineering and University Center for
Nano Science and Nanotechnology, Tel Aviv University, Tel-Aviv, 69978, Israel
| | | | | | | | | | | | | | | | | | - Maayan Matmor
- Department
of Materials Engineering and the Ilze Katz Institute for Nanoscale
Science and Technology, Ben Gurion University of the Negev, Beer-Sheva, Israel
| | - Ekaterina Gloukhikh
- The
Bio and Molecular Electronics Group, Department of Materials Science
and Engineering, Faculty of Engineering and University Center for
Nano Science and Nanotechnology, Tel Aviv University, Tel-Aviv, 69978, Israel
| | | | - Nurit Ashkenasy
- Department
of Materials Engineering and the Ilze Katz Institute for Nanoscale
Science and Technology, Ben Gurion University of the Negev, Beer-Sheva, Israel
| | - Paul W. M. Blom
- Molecular
Electronics Group, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Matthias Rögner
- Plant Biochemistry, Ruhr University Bochum, D-44780 Bochum, Germany
| | | | - Shachar Richter
- The
Bio and Molecular Electronics Group, Department of Materials Science
and Engineering, Faculty of Engineering and University Center for
Nano Science and Nanotechnology, Tel Aviv University, Tel-Aviv, 69978, Israel
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25
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Hasni I, Msilini N, Hamdani S, Tajmir-Riahi HA, Carpentier R. Characterization of the structural changes and photochemical activity of photosystem I under Al(3+) effect. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 149:292-9. [PMID: 26123191 DOI: 10.1016/j.jphotobiol.2015.06.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 06/08/2015] [Accepted: 06/14/2015] [Indexed: 11/27/2022]
Abstract
The photochemical activity of photosystem I (PSI) as affected by Al(3+) was investigated in thylakoid membranes and PSI submembrane fractions isolated from spinach. Biophysical and biochemical techniques such as oxygen uptake, light induced absorbance changes at 820nm, chlorophyll fluorescence emission, SDS-polyacrylamide gel electrophoresis, and FTIR spectroscopy have been used to analyze the sites and action modes of this cation on the PSI complex. Our results showed that Al(3+) above 3mM induces changes in the redox state of P700 reflected by an increase of P700 photooxidation phase and a delay of the slower rate of P700 re-reduction which reveals that Al(3+) exerted an inhibitory action at the donor side of PSI especially at plastocyanin (PC). Furthermore, results of P700 photooxidation monitored in the presence of DCMU with or without MV suggested that the same range of Al(3+) concentrations impairs the photochemical reaction centers (RC) of PSI, as shown by the decline in the amount of active population of P700, and disrupts the charge separation between P700 and the primary electron acceptor A0 leading to the inhibition of electron transfer at the acceptor side of PSI. These inhibitory actions were also accompanied by an impairment of the energy transfer from light harvesting complex (LHCI) to RC of PSI, following the disconnection of LHCI antenna as illustrated by an enhancement of chlorophyll fluorescence emission spectra at low temperature (77K). The above results coincided with FTIR measurements that indicated a conformational change of the protein secondary structures in PSI complex where 25% of α-helix was converted into β-sheet, β-antiparallel and turn structures. These structural changes in PSI complex proteins are closely related with the alteration photochemical activity of PSI including the inhibition of the electron transport through both acceptor and donor sides of PSI.
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Affiliation(s)
- Imed Hasni
- Groupe de Recherche en Biologie Végétale, Département de Chimie, Biochimie et Physique, Université du Québec à Trois-Rivières, Trois-Rivières, Qc G9A 5H7, Canada
| | - Najoua Msilini
- Laboratory of Physiology and Biochemistry of Salt Tolerance in Plants, Faculty of Sciences of Tunis, Campus University, 1060, Tunisia
| | - Saber Hamdani
- Plant Systems Biology Group, Partner Institute of Computational Biology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Heidar-Ali Tajmir-Riahi
- Groupe de Recherche en Biologie Végétale, Département de Chimie, Biochimie et Physique, Université du Québec à Trois-Rivières, Trois-Rivières, Qc G9A 5H7, Canada
| | - Robert Carpentier
- Groupe de Recherche en Biologie Végétale, Département de Chimie, Biochimie et Physique, Université du Québec à Trois-Rivières, Trois-Rivières, Qc G9A 5H7, Canada.
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26
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Synthesis and Biological Evaluation of N-Alkoxyphenyl-3-hydroxynaphthalene-2-carboxanilides. Molecules 2015; 20:9767-87. [PMID: 26023938 PMCID: PMC6272341 DOI: 10.3390/molecules20069767] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Accepted: 05/19/2015] [Indexed: 01/21/2023] Open
Abstract
A series of fifteen new N-alkoxyphenylanilides of 3-hydroxynaphthalene-2-carboxylic acid was prepared and characterized. Primary in vitro screening of the synthesized compounds was performed against Staphylococcus aureus, three methicillin-resistant S. aureus strains, Mycobacterium tuberculosis H37Ra and M. avium subsp. paratuberculosis. Some of the tested compounds showed antibacterial and antimycobacterial activity against the tested strains comparable with or higher than that of the standards ampicillin or rifampicin. 3-Hydroxy-N-(2-propoxyphenyl)naphthalene-2-carboxamide and N-[2-(but-2-yloxy)-phenyl]-3-hydroxynaphthalene-2-carboxamide had MIC = 12 µM against all methicillin-resistant S. aureus strains; thus their activity is 4-fold higher than that of ampicillin. The second mentioned compound as well as 3-hydroxy-N-[3-(prop-2-yloxy)phenyl]-naphthalene-2-carboxamide had MICs = 23 µM and 24 µM against M. tuberculosis respectively. N-[2-(But-2-yloxy)phenyl]-3-hydroxynaphthalene-2-carboxamide demonstrated higher activity against M. avium subsp. paratuberculosis than rifampicin. Screening of the cytotoxicity of the most effective antimycobacterial compounds was performed using THP-1 cells, and no significant lethal effect was observed for the most potent compounds. The compounds were additionally tested for their activity related to inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. N-(3-Ethoxyphenyl)-3-hydroxynaphthalene-2-carboxamide (IC50 = 4.5 µM) was the most active PET inhibitor. The structure-activity relationships are discussed.
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27
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Semelkova L, Konecna K, Paterova P, Kubicek V, Kunes J, Novakova L, Marek J, Naesens L, Pesko M, Kralova K, Dolezal M, Zitko J. Synthesis and Biological Evaluation of N-Alkyl-3-(alkylamino)-pyrazine-2-carboxamides. Molecules 2015; 20:8687-711. [PMID: 26007174 PMCID: PMC6272192 DOI: 10.3390/molecules20058687] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 05/08/2015] [Indexed: 01/23/2023] Open
Abstract
A series of N-alkyl-3-(alkylamino)pyrazine-2-carboxamides and their N-alkyl-3-chloropyrazine-2-carboxamide precursors were prepared. All compounds were characterized by analytical methods and tested for antimicrobial and antiviral activity. The antimycobacterial MIC values against Mycobacterium tuberculosis H37Rv of the most effective compounds, 3-(hexylamino)-, 3-(heptylamino)- and 3-(octylamino)-N-methyl-pyrazine-2-carboxamides 14‒16, was 25 μg/mL. The compounds inhibited photosystem 2 photosynthetic electron transport (PET) in spinach chloroplasts. This activity was strongly connected with the lipophilicity of the compounds. For effective PET inhibition longer alkyl chains in the 3-(alkylamino) substituent in the N-alkyl-3-(alkylamino)pyrazine-2-carboxamide molecule were more favourable than two shorter alkyl chains.
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Affiliation(s)
- Lucia Semelkova
- Faculty of Pharmacy, Charles University in Prague, Heyrovskeho 1203, Hradec Kralove 50005, Czech Republic.
| | - Klara Konecna
- Faculty of Pharmacy, Charles University in Prague, Heyrovskeho 1203, Hradec Kralove 50005, Czech Republic.
| | - Pavla Paterova
- Faculty of Pharmacy, Charles University in Prague, Heyrovskeho 1203, Hradec Kralove 50005, Czech Republic.
| | - Vladimir Kubicek
- Faculty of Pharmacy, Charles University in Prague, Heyrovskeho 1203, Hradec Kralove 50005, Czech Republic.
| | - Jiri Kunes
- Faculty of Pharmacy, Charles University in Prague, Heyrovskeho 1203, Hradec Kralove 50005, Czech Republic.
| | - Lucie Novakova
- Faculty of Pharmacy, Charles University in Prague, Heyrovskeho 1203, Hradec Kralove 50005, Czech Republic.
| | - Jan Marek
- Faculty of Pharmacy, Charles University in Prague, Heyrovskeho 1203, Hradec Kralove 50005, Czech Republic.
| | - Lieve Naesens
- Laboratory of Virology and Chemotherapy, Rega Institute KU Leuven, Minderbroedersstraat 10, Leuven B-3000, Belgium.
| | - Matus Pesko
- Department of Environmental Ecology, Faculty of Natural Sciences, Comenius University, Mlynska Dolina CH-2, Bratislava 84215, Slovakia.
| | - Katarina Kralova
- Institute of Chemistry, Faculty of Natural Sciences, Comenius University, Mlynska Dolina CH-2, Bratislava 84215, Slovakia.
| | - Martin Dolezal
- Faculty of Pharmacy, Charles University in Prague, Heyrovskeho 1203, Hradec Kralove 50005, Czech Republic.
| | - Jan Zitko
- Faculty of Pharmacy, Charles University in Prague, Heyrovskeho 1203, Hradec Kralove 50005, Czech Republic.
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28
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New potentially active pyrazinamide derivatives synthesized under microwave conditions. Molecules 2014; 19:9318-38. [PMID: 24995919 PMCID: PMC6271988 DOI: 10.3390/molecules19079318] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 06/17/2014] [Accepted: 06/26/2014] [Indexed: 11/21/2022] Open
Abstract
A series of 18 N-alkyl substituted 3-aminopyrazine-2-carboxamides was prepared in this work according to previously experimentally set and proven conditions using microwave assisted synthesis methodology. This approach for the aminodehalogenation reaction was chosen due to higher yields and shorter reaction times compared to organic reactions with conventional heating. Antimycobacterial, antibacterial, antifungal and photosynthetic electron transport (PET) inhibiting in vitro activities of these compounds were investigated. Experiments for the determination of lipophilicity were also performed. Only a small number of substances with alicyclic side chain showed activity against fungi which was the same or higher than standards and the biological efficacy of the compounds increased with rising lipophilicity. Nine pyrazinamide derivatives also inhibited PET in spinach chloroplasts and the IC50 values of these compounds varied in the range from 14.3 to 1590.0 μmol/L. The inhibitory activity was connected not only with the lipophilicity, but also with the presence of secondary amine fragment bounded to the pyrazine ring. Structure-activity relationships are discussed as well.
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29
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Zhang H, Lv J, Peng Y, Zhang S, An X, Xu H, Zhang J, Tian Y, Zheng W, Zheng T. Cell death in a harmful algal bloom causing species Alexandrium tamarense upon an algicidal bacterium induction. Appl Microbiol Biotechnol 2014; 98:7949-58. [PMID: 24962118 DOI: 10.1007/s00253-014-5886-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 06/03/2014] [Accepted: 06/08/2014] [Indexed: 11/27/2022]
Abstract
Harmful algal blooms occur throughout the world, destroying aquatic ecosystems and threatening human health. The culture supernatant of the marine algicidal bacteria DHQ25 was able to lysis dinoflagellate Alexandrium tamarense. Loss of photosynthetic pigments, accompanied by a decline in Photosystem II (PSII) photochemical efficiency (Fv/Fm), in A. tamarense was detected under bacterial supernatant stress. Transmission electron microscope analysis showed obvious morphological modifications of chloroplast dismantling as a part of the algicidal process. The PSII electron transport chain was seriously blocked, with its reaction center damaged. This damage was detected in a relative transcriptional level of psbA and psbD genes, which encode the D1 and D2 proteins in the PSII reaction center. And the block in the electron transport chain of PSII might generate excessive reactive oxygen species (ROS) which could destroy the membrane system and pigment synthesis and activated enzymic antioxidant systems including superoxide dismutase (SOD) and catalase (CAT). This study indicated that marine bacteria with indirect algicidal activity played an important role in the changes of photosynthetic process in a harmful algal bloom species.
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Affiliation(s)
- Huajun Zhang
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, 422, Siming Nan Road, Xiamen, 361005, China
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30
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Deák Z, Sass L, Kiss E, Vass I. Characterization of wave phenomena in the relaxation of flash-induced chlorophyll fluorescence yield in cyanobacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1522-32. [PMID: 24434028 DOI: 10.1016/j.bbabio.2014.01.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 12/30/2013] [Accepted: 01/07/2014] [Indexed: 12/25/2022]
Abstract
Fluorescence yield relaxation following a light pulse was studied in various cyanobacteria under aerobic and microaerobic conditions. In Synechocystis PCC 6803 fluorescence yield decays in a monotonous fashion under aerobic conditions. However, under microaerobic conditions the decay exhibits a wave feature showing a dip at 30-50 ms after the flash followed by a transient rise, reaching maximum at ~1s, before decaying back to the initial level. The wave phenomenon can also be observed under aerobic conditions in cells preilluminated with continuous light. Illumination preconditions cells for the wave phenomenon transiently: for few seconds in Synechocystis PCC 6803, but up to one hour in Thermosynechocystis elongatus BP-1. The wave is eliminated by inhibition of plastoquinone binding either to the QB site of Photosystem-II or the Qo site of cytochrome b6f complex by 3-(3',4'-dichlorophenyl)-1,1-dimethylurea or 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone, respectively. The wave is also absent in mutants, which lack either Photosystem-I or the NAD(P)H-quinone oxidoreductase (NDH-1) complex. Monitoring the redox state of the plastoquinone pool revealed that the dip of the fluorescence wave corresponds to transient oxidation, whereas the following rise to re-reduction of the plastoquinone pool. It is concluded that the unusual wave feature of fluorescence yield relaxation reflects transient oxidation of highly reduced plastoquinone pool by Photosystem-I followed by its re-reduction from stromal components via the NDH-1 complex, which is transmitted back to the fluorescence yield modulator primary quinone electron acceptor via charge equilibria. Potential applications of the wave phenomenon in studying photosynthetic and respiratory electron transport are discussed. This article is part of a special issue entitled: photosynthesis research for sustainability: keys to produce clean energy.
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Affiliation(s)
- Zsuzsanna Deák
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Temesvari krt. 62, 6726 Szeged, Hungary
| | - László Sass
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Temesvari krt. 62, 6726 Szeged, Hungary
| | - Eva Kiss
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Temesvari krt. 62, 6726 Szeged, Hungary
| | - Imre Vass
- Institute of Plant Biology, Biological Research Centre of the Hungarian Academy of Sciences, Temesvari krt. 62, 6726 Szeged, Hungary.
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31
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Nguyen K, Bruce BD. Growing green electricity: progress and strategies for use of photosystem I for sustainable photovoltaic energy conversion. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1553-66. [PMID: 24388916 DOI: 10.1016/j.bbabio.2013.12.013] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 12/17/2013] [Accepted: 12/25/2013] [Indexed: 10/25/2022]
Abstract
Oxygenic photosynthesis is driven via sequential action of Photosystem II (PSII) and (PSI)reaction centers via the Z-scheme. Both of these pigment-membrane protein complexes are found in cyanobacteria, algae, and plants. Unlike PSII, PSI is remarkably stable and does not undergo limiting photo-damage. This stability, as well as other fundamental structural differences, makes PSI the most attractive reaction centers for applied photosynthetic applications. These applied applications exploit the efficient light harvesting and high quantum yield of PSI where the isolated PSI particles are redeployed providing electrons directly as a photocurrent or, via a coupled catalyst to yield H₂. Recent advances in molecular genetics, synthetic biology, and nanotechnology have merged to allow PSI to be integrated into a myriad of biohybrid devices. In photocurrent producing devices, PSI has been immobilized onto various electrode substrates with a continuously evolving toolkit of strategies and novel reagents. However, these innovative yet highly variable designs make it difficult to identify the rate-limiting steps and/or components that function as bottlenecks in PSI-biohybrid devices. In this study we aim to highlight these recent advances with a focus on identifying the similarities and differences in electrode surfaces, immobilization/orientation strategies, and artificial redox mediators. Collectively this work has been able to maintain an annual increase in photocurrent density (Acm⁻²) of ~10-fold over the past decade. The potential drawbacks and attractive features of some of these schemes are also discussed with their feasibility on a large-scale. As an environmentally benign and renewable resource, PSI may provide a new sustainable source of bioenergy. This article is part of a special issue entitled: photosynthesis research for sustainability: keys to produce clean energy.
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Affiliation(s)
- Khoa Nguyen
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - Barry D Bruce
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA; Department of Microbiology, University of Tennessee, Knoxville, TN 37996, USA; Bredesen Center for Interdisciplinary Research and Education, University of Tennessee, Knoxville, TN 37996, USA.
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Koeda S, Umezaki K, Noji T, Ikeda A, Kawakami K, Kondo M, Yamamoto Y, Shen JR, Taga K, Dewa T, Ito S, Nango M, Tanaka T, Mizuno T. Application of peptide gemini surfactants as novel solubilization surfactants for photosystems I and II of cyanobacteria. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:11667-11680. [PMID: 23957575 DOI: 10.1021/la402167v] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We designed novel peptide gemini surfactants (PG-surfactants), DKDKC12K and DKDKC12D, which can solubilize Photosystem I (PSI) of Thermosynecoccus elongatus and Photosystem II (PSII) of Thermosynecoccus vulcanus in an aqueous buffer solution. To assess the detailed effects of PG-surfactants on the original supramolecular membrane protein complexes and functions of PSI and PSII, we applied the surfactant exchange method to the isolated PSI and PSII. Spectroscopic properties, light-induced electron transfer activity, and dynamic light scattering measurements showed that PSI and PSII could be solubilized not only with retention of the original supramolecular protein complexes and functions but also without forming aggregates. Furthermore, measurement of the lifetime of light-induced charge-separation state in PSI revealed that both surfactants, especially DKDKC12D, displayed slight improvement against thermal denaturation below 60 °C compared with that using β-DDM. This degree of improvement in thermal resistance still seems low, implying that the peptide moieties did not interact directly with membrane protein surfaces. By conjugating an electron mediator such as methyl viologen (MV(2+)) to DKDKC12K (denoted MV-DKDKC12K), we obtained derivatives that can trap the generated reductive electrons from the light-irradiated PSI. After immobilization onto an indium tin oxide electrode, a cathodic photocurrent from the electrode to the PSI/MV-DKDKC12K conjugate was observed in response to the interval of light irradiation. These findings indicate that the PG-surfactants DKDKC12K and DKDKC12D provide not only a new class of solubilization surfactants but also insights into designing other derivatives that confer new functions on PSI and PSII.
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Affiliation(s)
- Shuhei Koeda
- Graduate School of Engineering, Nagoya Institute of Technology , Gokiso-cho, Showa-ku, Nagoya, Aichi 466-8555, Japan
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Antimycobacterial and photosynthetic electron transport inhibiting activity of ring-substituted 4-arylamino-7-chloroquinolinium chlorides. Molecules 2013; 18:10648-70. [PMID: 24002140 PMCID: PMC6270397 DOI: 10.3390/molecules180910648] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 08/19/2013] [Accepted: 08/26/2013] [Indexed: 11/17/2022] Open
Abstract
In this study, a series of twenty-five ring-substituted 4-arylamino-7-chloroquinolinium chlorides were prepared and characterized. The compounds were tested for their activity related to inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts and also primary in vitro screening of the synthesized compounds was performed against mycobacterial species. 4-[(2-Bromophenyl)amino]-7-chloroquinolinium chloride showed high biological activity against M. marinum, M. kansasii, M. smegmatis and 7-chloro-4-[(2-methylphenyl)amino]quinolinium chloride demonstrated noteworthy biological activity against M. smegmatis and M. avium subsp. paratuberculosis. The most effective compounds demonstrated quite low toxicity (LD₅₀ > 20 μmol/L) against the human monocytic leukemia THP-1 cell line within preliminary in vitro cytotoxicity screening. The tested compounds were found to inhibit PET in photosystem II. The PET-inhibiting activity expressed by IC₅₀ value of the most active compound 7-chloro-4-[(3-trifluoromethylphenyl)amino]quinolinium chloride was 27 μmol/L and PET-inhibiting activity of ortho-substituted compounds was significantly lower than this of meta- and para-substituted ones. The structure-activity relationships are discussed for all compounds.
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Antibacterial and herbicidal activity of ring-substituted 2-hydroxynaphthalene-1-carboxanilides. Molecules 2013; 18:9397-419. [PMID: 23924993 PMCID: PMC6270026 DOI: 10.3390/molecules18089397] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 08/01/2013] [Accepted: 08/02/2013] [Indexed: 11/17/2022] Open
Abstract
In this study, a series of twenty-two ring-substituted 2-hydroxynaphthalene-1‑carboxanilides were prepared and characterized. Primary in vitro screening of the synthesized compounds was performed against Staphylococcus aureus, three methicillin-resistant S. aureus strains, Mycobacterium marinum, M. kasasii, M. smegmatis. and M. avium paratuberculosis. The compounds were also tested for their activity related to inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. 2-Hydroxy-N-phenylnaphthalene-1-carboxanilide and 2-hydroxy-N-(3-trifluoromethylphenyl)naphthalene-1-carboxamide (IC₅₀ = 29 µmol/L) were the most active PET inhibitors. Some of tested compounds showed the antibacterial and antimycobacterial activity against the tested strains comparable or higher than the standards ampicillin or isoniazid. Thus, for example, 2-hydroxy-N-(3-nitrophenyl)naphthalene-1-carboxamide showed MIC = 26.0 µmol/L against methicillin-resistant S. aureus and MIC = 51.9 µmol/L against M. marinum, or 2-hydroxy-N-phenylnaphthalene-1-carboxamide demonstrated MIC = 15.2 µmol/L against M. kansasii. The structure-activity relationships for all compounds are discussed.
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Antibacterial and herbicidal activity of ring-substituted 3-hydroxynaphthalene-2-carboxanilides. Molecules 2013; 18:7977-97. [PMID: 23884130 PMCID: PMC6270455 DOI: 10.3390/molecules18077977] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Revised: 06/17/2013] [Accepted: 07/04/2013] [Indexed: 11/30/2022] Open
Abstract
In this study, a series of twenty-two ring-substituted 3-hydroxy-N-phenylnaphthalene-2-carboxanilides were prepared and characterized. The compounds were tested for their activity related to inhibition of photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. Primary in vitro screening of the synthesized compounds was also performed against four Staphylococcus strains and against two mycobacterial species. 3-Hydroxy-N-(2-methoxyphenyl)naphthalene-2-carboxamide showed high biological activity (MIC = 55.0 µmol/L) against S. aureus as well as methicillin-resistant strains. N-(2-Fluorophenyl)-3-hydroxynaphthalene-2-carboxamide showed higher activity (MIC = 28.4 µmol/L) against M. marinum than the standard isoniazid and 3-hydroxy-N-(4-nitrophenyl)naphthalene-2-carboxamide expressed higher activity (MIC = 13.0 µmol/L) against M. kansasii than the standard isoniazid. Cytotoxicity assay of effective antimicrobial compounds was performed using the human monocytic leukemia THP-1 cell line. The PET-inhibiting activity expressed by IC50 value of the most active compound 3-hydroxy-N-(3-nitrophenyl)naphthalene-2-carboxamide was 16.9 μmol/L. The structure-activity relationships of all compounds are discussed.
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Yan X, Faulkner CJ, Jennings GK, Cliffel DE. Photosystem I in Langmuir-Blodgett and Langmuir-Schaefer monolayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:15080-15086. [PMID: 23009258 DOI: 10.1021/la302611a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Photosystem I (PSI) is a membrane protein complex that generates photoinduced electrons and transfers them across the thylakoid membrane during photosynthesis. The PSI complex, separated from spinach leaves, was spread onto the air-water interface as a monolayer and transferred onto a gold electrode surface that was precoated with a self-assembled monolayer (SAM). The electrochemical properties of the transferred PSI monolayer, including cyclic voltammetry and photoinduced chronoamperometry, were measured. The results showed that PSI retained its bioactivity after the manipulation. Its capability of converting photoenergy into electrical potential was demonstrated by its reducing an electron acceptor, dichloroindophenol (DCIP), and by oxidizing an electron donor, sodium ascorbate (ASC). We have shown that the protein has two possible orientations at the water interface. The orientation distribution was determined by comparing the controlled reductive and oxidative photocurrents generated from Langmuir-Blodgett and Langmuir-Schaefer monolayers.
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Affiliation(s)
- Xun Yan
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235-1822, United States
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Bharati A, Kar M, Sabat SC. Artemisinin inhibits chloroplast electron transport activity: mode of action. PLoS One 2012; 7:e38942. [PMID: 22719995 PMCID: PMC3374801 DOI: 10.1371/journal.pone.0038942] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Accepted: 05/14/2012] [Indexed: 11/18/2022] Open
Abstract
Artemisinin, a secondary metabolite produced in Artemisia plant species, besides having antimalarial properties is also phytotoxic. Although, the phytotoxic activity of the compound has been long recognized, no information is available on the mechanism of action of the compound on photosynthetic activity of the plant. In this report, we have evaluated the effect of artemisinin on photoelectron transport activity of chloroplast thylakoid membrane. The inhibitory effect of the compound, under in vitro condition, was pronounced in loosely and fully coupled thylakoids; being strong in the former. The extent of inhibition was drastically reduced in the presence of uncouplers like ammonium chloride or gramicidin; a characteristic feature described for energy transfer inhibitors. The compound, on the other hand, when applied to plants (in vivo), behaved as a potent inhibitor of photosynthetic electron transport. The major site of its action was identified to be the Q(B); the secondary quinone moiety of photosystemII complex. Analysis of photoreduction kinetics of para-benzoquinone and duroquinone suggest that the inhibition leads to formation of low pool of plastoquinol, which becomes limiting for electron flow through photosystemI. Further it was ascertained that the in vivo inhibitory effect appeared as a consequence of the formation of an unidentified artemisinin-metabolite rather than by the interaction of the compound per se. The putative metabolite of artemisinin is highly reactive in instituting the inhibition of photosynthetic electron flow eventually reducing the plant growth.
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Affiliation(s)
- Adyasha Bharati
- Gene Function and Regulation, Stress Biology Laboratory, Institute of Life Sciences, Bhubaneswar, Odisha, India
| | - Monaranjan Kar
- Department of Botany, Utkal University, Vani Vihar, Bhubaneswar, Odisha, India
| | - Surendra Chandra Sabat
- Gene Function and Regulation, Stress Biology Laboratory, Institute of Life Sciences, Bhubaneswar, Odisha, India
- * E-mail:
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Chen X, Li W, Lu Q, Wen X, Li H, Kuang T, Li Z, Lu C. The xanthophyll cycle and antioxidative defense system are enhanced in the wheat hybrid subjected to high light stress. JOURNAL OF PLANT PHYSIOLOGY 2011; 168:1828-36. [PMID: 21737175 DOI: 10.1016/j.jplph.2011.05.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 05/13/2011] [Accepted: 05/13/2011] [Indexed: 05/08/2023]
Abstract
Although the wheat hybrids have often shown higher grain yields, the physiological basis of the higher yields remains unknown. Previous studies suggest that tolerance to photoinhibition in the hybrid may be one of the physiological bases (Yang et al., 2006, Plant Sci 171:389-97). The objective of this study was to further investigate the possible mechanism responsible for tolerance to photoinhibition in the hybrid. Photosystem II (PSII) photochemistry, the xanthophyll cycle, and antioxidative defense system were compared between the hybrid and its parents subjected to high light stress (1500μmolm(-2)s(-1)). The analyses of oxygen-evolving activity, chlorophyll fluorescence, and protein blotting demonstrated that the higher tolerance in the hybrid than in its parents was associated with its higher tolerance of PSII to photoinhibition. High light induced an increase in non-photochemical quenching, and this increase was greater in the hybrid than in its parents. There were no differences in the pool size of the xanthophyll cycle between the hybrid and its parents. The content of violaxanthin decreased significantly, whereas the content of zeaxanthin+antherxanthin increased considerably during high light treatments. However, the decrease in violaxanthin content and the increase in zeaxanthin+antherxanthin content were greater in the hybrid than in its parents. High light resulted in a significant accumulation of H(2)O(2), O(2)(-) and catalytic Fe, and this accumulation was less in the hybrid than in its parents. High light induced a significant increase in the activities of superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, and monodehydroascorbate reductase, and these increases were greater in the hybrid than its parents. These results suggest that the higher tolerance to photoinhibition in the hybrid may be associated with its higher capacity for antioxidative defense metabolism and the xanthophyll cycle.
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Affiliation(s)
- Xiaoying Chen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
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Suzuki K, Ohmori Y, Ratel E. High Root Temperature Blocks Both Linear and Cyclic Electron Transport in the Dark During Chilling of the Leaves of Rice Seedlings. ACTA ACUST UNITED AC 2011; 52:1697-707. [DOI: 10.1093/pcp/pcr104] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Singh DK, Maximova SN, Jensen PJ, Lehman BL, Ngugi HK, McNellis TW. FIBRILLIN4 is required for plastoglobule development and stress resistance in apple and Arabidopsis. PLANT PHYSIOLOGY 2010; 154:1281-93. [PMID: 20813909 PMCID: PMC2971606 DOI: 10.1104/pp.110.164095] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Accepted: 08/31/2010] [Indexed: 05/20/2023]
Abstract
The fibrillins are a large family of chloroplast proteins that have been linked with stress tolerance and disease resistance. FIBRILLIN4 (FIB4) is found associated with the photosystem II light-harvesting complex, thylakoids, and plastoglobules, which are chloroplast compartments rich in lipophilic antioxidants. For this study, FIB4 expression was knocked down in apple (Malus 3 domestica) using RNA interference. Plastoglobule osmiophilicity was decreased in fib4 knockdown (fib4 KD) tree chloroplasts compared with the wild type, while total plastoglobule number was unchanged. Compared with the wild type, net photosynthetic CO(2) fixation in fib4 KD trees was decreased at high light intensity but was increased at low light intensity. Furthermore, fib4 KD trees produced more anthocyanins than the wild type when transferred from low to high light intensity, indicating greater sensitivity to high light stress. Relative to the wild type, fib4 KD apples were more sensitive to methyl viologen and had higher superoxide levels during methyl viologen treatment. Arabidopsis (Arabidopsis thaliana) fib4 mutants and fib4 KD apples were more susceptible than their wild-type counterparts to the bacterial pathogens Pseudomonas syringae pathovar tomato and Erwinia amylovora, respectively, and were more sensitive to ozone-induced tissue damage. Following ozone stress, plastoglobule osmiophilicity decreased in wild-type apple and remained low in fib4 KD trees; total plastoglobule number increased in fib4 KD apples but not in the wild type. These results indicate that FIB4 is required for plastoglobule development and resistance to multiple stresses. This study suggests that FIB4 is involved in regulating plastoglobule content and that defective regulation of plastoglobule content leads to broad stress sensitivity and altered photosynthetic activity.
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Affiliation(s)
| | | | | | | | | | - Timothy W. McNellis
- Intercollege Graduate Degree Program in Plant Biology (D.K.S.), Department of Plant Pathology (D.K.S., P.J.J., H.K.N., T.W.M.), and Department of Horticulture (S.N.M.), The Pennsylvania State University, University Park, Pennsylvania 16802; The Pennsylvania State University Fruit Research and Extension Center, Biglerville, Pennsylvania 17307 (B.L.L., H.K.N.)
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Allakhverdiev SI, Murata N. Salt stress inhibits photosystems II and I in cyanobacteria. PHOTOSYNTHESIS RESEARCH 2008; 98:529-39. [PMID: 18670904 DOI: 10.1007/s11120-008-9334-x] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Accepted: 07/12/2008] [Indexed: 05/03/2023]
Abstract
Recent studies of responses of cyanobacterial cells to salt stress have revealed that the NaCl-induced decline in the photosynthetic activities of photosystems II and I involves rapid and slow changes. The rapid decreases in the activities of both photosystems, which occur within a few minutes, are reversible and are associated with osmotic effects, which induce the efflux of water from the cytosol through water channels and rapidly increase intracellular concentrations of salts. Slower decreases in activity, which occur within hours, are irreversible and are associated with ionic effects that are due to the influx of Na(+) and Cl(-) ions through K(+)(Na(+)) channels and, probably, Cl(-) channels, with resultant dissociation of extrinsic proteins from photosystems. In combination with light stress, salt stress significantly stimulates photoinhibition by inhibiting repair of photodamaged photosystem II. Tolerance of photosystems to salt stress can be enhanced by genetically engineered increases in the unsaturation of fatty acids in membrane lipids and by intracellular synthesis of compatible solutes, such as glucosylglycerol and glycinebetaine. In this review, we summarize recent progress in research on the effects of salt stress on photosynthesis in cyanobacteria.
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Affiliation(s)
- Suleyman I Allakhverdiev
- Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
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Effects of (60)Co gamma radiation on thylakoid membrane functions in Anacystis nidulans. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2008; 91:9-19. [PMID: 18316199 DOI: 10.1016/j.jphotobiol.2008.01.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2007] [Revised: 01/11/2008] [Accepted: 01/13/2008] [Indexed: 11/24/2022]
Abstract
In photosynthetic organisms oxidative stress is known to result in photoinactivation of photosynthetic machinery. We investigated effects of (60)Co gamma radiation, which generates oxidative stress, on thylakoid structure and function in cyanobacteria. Cells of unicellular, non-nitrogen fixing cyanobacterium Anacystis nidulans (Synechococcus sp.) showed D(10) value of 257 Gy of (60)Co gamma radiation. When measured immediately after exposure, cells irradiated with 1500 Gy (lethal dose) of (60)Co gamma radiation did not show any differences in photosynthetic functions such as CO(2) fixation, O(2) evolution and partial reactions of photosynthetic electron transport in comparison to unirradiated cells. Incubation of irradiated cells for 24h in light or dark resulted in decline in photosynthesis. The decline in photosynthesis was higher in the cells incubated in light as compared to the cells incubated in dark. Among the partial reactions of electron transport, only PSII activity declined drastically after incubation of irradiated samples. This was also supported by the analysis of membrane functions using thermoluminescence. Exposure of cyanobacteria to high doses of (60)Co gamma radiation did not affect the thylakoid membrane ultrastructure immediately after exposure as shown by electron microscopy. The level of reactive oxygen species (ROS) in irradiated cells was 20 times higher as compared to control. In irradiated cells de novo protein synthesis was reduced considerably immediately after irradiation. Treatment of cells with tetracycline also affected photosynthesis as in irradiated cells. The results showed that photoinhibition of photosynthetic apparatus after incubation of irradiated cells was probably augmented due to reduced protein synthesis. Active photosynthesis is known to require uninterrupted replenishment of some of the proteins involved in electron transport chain. The defective thylakoid membrane biogenesis may be leading to photosynthetic decline post-irradiation.
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Lemieux S, Carpentier R. PROPERTIES OF IMMOBILIZED THYLAKOID MEMBRANES IN A PHOTOSYNTHETIC PHOTOELECTROCHEMICAL CELL. Photochem Photobiol 2008. [DOI: 10.1111/j.1751-1097.1988.tb02795.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Suh HJ, Sook Kim C, Lee JY, Jung J. Photodynamic Effect of Iron Excess on Photosystem II Function in Pea Plants¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2002)0750513peoieo2.0.co2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Hagiwara SY, Bolige A, Zhang Y, Takahashi M, Yamagishi A, Goto K. Circadian Gating of Photoinduction of Commitment to Cell-cycle Transitions in Relation to Photoperiodic Control of Cell Reproduction in Euglena¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2002)0760105cgopoc2.0.co2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Suh HJ, Kim CS, Jung J. Cytochrome b6/f Complex as an Indigenous Photodynamic Generator of Singlet Oxygen in Thylakoid Membranes. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2000)0710103cbfcaa2.0.co2] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Trebst A. Inhibitors in the functional dissection of the photosynthetic electron transport system. PHOTOSYNTHESIS RESEARCH 2007; 92:217-24. [PMID: 17647089 DOI: 10.1007/s11120-007-9213-x] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2007] [Accepted: 06/08/2007] [Indexed: 05/09/2023]
Abstract
The significance of inhibitors and artificial electron acceptor and donor systems as experimental tools for studying the photosynthetic system is described by reviewing early classical articles. The historical development in unravelling the role and sequence of electron carriers and energy conserving sites in the electron transport chain is acknowledged. Emphasis is given to inhibitors of the acceptor side of photosystem II and of the plastoquinol oxidation site in the cytochrome b6/f complex. Their role in regulatory processes under redox control is introduced.
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Affiliation(s)
- Achim Trebst
- Plant Biochemistry, Ruhr-University, 44780 Bochum, Germany.
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Yang X, Wen X, Gong H, Lu Q, Yang Z, Tang Y, Liang Z, Lu C. Genetic engineering of the biosynthesis of glycinebetaine enhances thermotolerance of photosystem II in tobacco plants. PLANTA 2007; 225:719-33. [PMID: 16953431 DOI: 10.1007/s00425-006-0380-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Accepted: 08/08/2006] [Indexed: 05/11/2023]
Abstract
Genetically engineered tobacco (Nicotiana tabacum L.) with the ability to accumulate glycinebetaine was established. The wild type and transgenic plants were exposed to heat treatment (25-50 degrees C) for 4 h in the dark and under growth light intensity (300 mumol m(-2) s(-1)). The analyses of oxygen-evolving activity and chlorophyll fluorescence demonstrated that photosystem II (PSII) in transgenic plants showed higher thermotolerance than in wild type plants in particular when heat stress was performed in the light, suggesting that the accumulation of glycinebetaine leads to increased tolerance to heat-enhanced photoinhibition. This increased tolerance was associated with an improvement on thermostability of the oxygen-evolving complex and the reaction center of PSII. The enhanced tolerance was caused by acceleration of the repair of PSII from heat-enhanced photoinhibition. Under heat stress, there was a significant accumulation of H(2)O(2), O (2) (-) and catalytic Fe in wild type plants but this accumulation was much less in transgenic plants. Heat stress significantly decreased the activities of catalase, ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, and monodehydroascorbate reductase in wild type plants whereas the activities of these enzymes either decreased much less or maintained or even increased in transgenic plants. In addition, heat stress increased the activity of superoxide dismutase in wild type plants but this increase was much greater in transgenic plants. Furthermore, transgenic plants also showed higher content of ascorbate and reduced glutathione than that of wild type plants under heat stress. The results suggest that the increased thermotolerance induced by accumulation of glycinebetaine in vivo was associated with the enhancement of the repair of PSII from heat-enhanced photo inhibition, which might be due to less accumulation of reactive oxygen species in transgenic plants.
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Affiliation(s)
- Xinghong Yang
- Photosynthesis Research Center, Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, People's Republic of China
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Lohmann A, Schöttler MA, Bréhélin C, Kessler F, Bock R, Cahoon EB, Dörmann P. Deficiency in Phylloquinone (Vitamin K1) Methylation Affects Prenyl Quinone Distribution, Photosystem I Abundance, and Anthocyanin Accumulation in the Arabidopsis AtmenG Mutant. J Biol Chem 2006; 281:40461-72. [PMID: 17082184 DOI: 10.1074/jbc.m609412200] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phylloquinone (vitamin K(1)) is synthesized in cyanobacteria and in chloroplasts of plants, where it serves as electron carrier of photosystem I. The last step of phylloquinone synthesis in cyanobacteria is the methylation of 2-phytyl-1,4-naphthoquinone by the menG gene product. Here, we report that the uncharacterized Arabidopsis gene At1g23360, which shows sequence similarity to menG, functionally complements the Synechocystis menG mutant. An Arabidopsis mutant, AtmenG, carrying a T-DNA insertion in the gene At1g23360 is devoid of phylloquinone, but contains an increased amount of 2-phytyl-1,4-naphthoquinone. Phylloquinone and 2-phytyl-1,4-naphthoquinone in thylakoid membranes of wild type and AtmenG, respectively, predominantly localize to photosystem I, whereas excess amounts of prenyl quinones are stored in plastoglobules. Photosystem I reaction centers are decreased in AtmenG plants under high light, as revealed by immunoblot and spectroscopic measurements. Anthocyanin accumulation and chalcone synthase (CHS1) transcription are affected during high light exposure, indicating that alterations in photosynthesis in AtmenG affect gene expression in the nucleus. Photosystem II quantum yield is decreased under high light. Therefore, the loss of phylloquinone methylation affects photosystem I stability or turnover, and the limitation in functional photosystem I complexes results in overreduction of photosystem II under high light.
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Affiliation(s)
- Antje Lohmann
- Department of Molecular Physiology, Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam, Germany
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Nakamura K, Hihara Y. Photon flux density-dependent gene expression in Synechocystis sp. PCC 6803 is regulated by a small, redox-responsive, LuxR-type regulator. J Biol Chem 2006; 281:36758-66. [PMID: 17035238 DOI: 10.1074/jbc.m606797200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The expression of many cyanobacterial genes is regulated by the redox state of the photosynthetic electron transport chain. However, factors involved in this regulation have not been identified. In this study, we demonstrate that a small LuxR-type regulator in Synechocystis sp. PCC 6803, PedR (Ssl0564), senses the activity of photosynthetic electron transport to achieve the photon flux density-dependent transcriptional regulation. PedR is constitutively expressed in Synechocystis cells and exists as a dimer bridged by intermolecular disulfide bond(s). It activates the expression of chlL, chlN, chlB, and slr1957 and represses that of ndhD2, rpe, and the pedR (ssl0564)-sll0296 operon under conditions where the activity of photosynthetic electron transport is low. When the supply of reducing equivalents from photosynthetic electron transport chain increases upon the elevation of photon flux density, PedR is inactivated through its conformational change within 5 min. This mechanism enables transient induction or repression of the target genes in response to sudden changes in light environment. The fact that orthologs of PedR are conserved among all the cyanobacterial genomes sequenced so far indicates that this type of transcriptional regulation is essential for cyanobacteria to acclimate to changing environments.
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Affiliation(s)
- Kinu Nakamura
- Department of Biochemistry and Molecular Biology, Faculty of Science, Saitama University, Saitama 338-8570, Japan
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