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Lambreva MD, Zobnina V, Antal TK, Peeva VN, Giardi MT, Bertalan I, Johanningmeier U, Virtanen O, Ray M, Mulo P, Polticelli F, Tyystjärvi E, Rea G. Redesign of the Chlamydomonas reinhardtii Q B binding niche reveals photosynthesis works in the absence of a driving force for Q A-Q B electron transfer. PHYSIOLOGIA PLANTARUM 2024; 176:e70008. [PMID: 39673282 PMCID: PMC11645544 DOI: 10.1111/ppl.70008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2024] [Revised: 11/14/2024] [Accepted: 11/21/2024] [Indexed: 12/16/2024]
Abstract
An in silico redesign of the secondary quinone electron acceptor (QB) binding pocket of the D1 protein of Photosystem II (PSII) suggested that mutations of the F265 residue would affect atrazine binding. Chlamydomonas reinhardtii mutants F265T and F265S were produced to obtain atrazine-hypersensitive strains for biosensor applications, and the mutants were indeed found to be more atrazine-sensitive than the reference strain IL. Fluorescence and thermoluminescence data agree with a weak driving force and confirm slow electron transfer but cannot exclude an additional effect on protonation of the secondary quinone. Both mutants grow autotrophically, indicating that PSII requires strong light for optimal function, as was the case in the ancestral homodimeric reaction center.
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Affiliation(s)
- Maya D. Lambreva
- Institute for Biological Systems, National Research CouncilMonterotondo Stazione (RM)Italy
| | | | - Taras K. Antal
- Laboratory of integrated ecological researchPskov State UniversityPskovRussia
| | - Violeta N. Peeva
- Bulgarian Academy of SciencesInstitute of Plant Physiology and GeneticsSofiaBulgaria
| | - Maria Teresa Giardi
- Biosensor SrlFormelloRomeItaly
- Institute of Crystallography, National Research CouncilMonterotondo Stazione (RM)Italy
| | - Ivo Bertalan
- Institut für Pflanzenphysiologie, Martin‐Luther‐Universität Halle‐WittenbergHalle (Saale)Germany
| | - Udo Johanningmeier
- Institut für Pflanzenphysiologie, Martin‐Luther‐Universität Halle‐WittenbergHalle (Saale)Germany
| | - Olli Virtanen
- Department of Life Technologies/Molecular Plant BiologyUniversity of TurkuTurkuFinland
- Department of Physics and AstronomyVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Mithila Ray
- Department of Life Technologies/Molecular Plant BiologyUniversity of TurkuTurkuFinland
| | - Paula Mulo
- Department of Life Technologies/Molecular Plant BiologyUniversity of TurkuTurkuFinland
| | - Fabio Polticelli
- Department of SciencesUniversity Roma TreRomeItaly
- National Institute of Nuclear Physics, Roma Tre SectionRomeItaly
| | - Esa Tyystjärvi
- Department of Life Technologies/Molecular Plant BiologyUniversity of TurkuTurkuFinland
| | - Giuseppina Rea
- Institute of Crystallography, National Research CouncilMonterotondo Stazione (RM)Italy
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Wei X, Reddy VS, Gao S, Zhai X, Li Z, Shi J, Niu L, Zhang D, Ramakrishna S, Zou X. Recent advances in electrochemical cell-based biosensors for food analysis: Strategies for sensor construction. Biosens Bioelectron 2024; 248:115947. [PMID: 38181518 DOI: 10.1016/j.bios.2023.115947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/07/2024]
Abstract
Owing to their advantages such as great specificity, sensitivity, rapidity, and possibility of noninvasive and real-time monitoring, electrochemical cell-based biosensors (ECBBs) have been a powerful tool for food analysis encompassing the areas of nutrition, flavor, and safety. Notably, the distinctive biological relevance of ECBBs enables them to mimic physiological environments and reflect cellular behaviors, leading to valuable insights into the biological function of target components in food. Compared with previous reviews, this review fills the current gap in the narrative of ECBB construction strategies. The review commences by providing an overview of the materials and configuration of ECBBs, including cell types, cell immobilization strategies, electrode modification materials, and electrochemical sensing types. Subsequently, a detailed discussion is presented on the fabrication strategies of ECBBs in food analysis applications, which are categorized based on distinct signal sources. Lastly, we summarize the merits, drawbacks, and application scope of these diverse strategies, and discuss the current challenges and future perspectives of ECBBs. Consequently, this review provides guidance for the design of ECBBs with specific functions and promotes the application of ECBBs in food analysis.
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Affiliation(s)
- Xiaoou Wei
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, PR China; Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore
| | - Vundrala Sumedha Reddy
- Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore
| | - Shipeng Gao
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, PR China
| | - Xiaodong Zhai
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, PR China
| | - Zhihua Li
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, PR China
| | - Jiyong Shi
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, PR China
| | - Lidan Niu
- Key Laboratory of Condiment Supervision Technology for State Market Regulation, Chongqing Institute for Food and Drug Control, Chongqing 401121, PR China
| | - Di Zhang
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, PR China; Key Laboratory of Condiment Supervision Technology for State Market Regulation, Chongqing Institute for Food and Drug Control, Chongqing 401121, PR China.
| | - Seeram Ramakrishna
- Department of Mechanical Engineering, National University of Singapore, Singapore 117575, Singapore.
| | - Xiaobo Zou
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, PR China.
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3
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Deepika C, Wolf J, Roles J, Ross I, Hankamer B. Sustainable Production of Pigments from Cyanobacteria. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2023; 183:171-251. [PMID: 36571616 DOI: 10.1007/10_2022_211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Pigments are intensely coloured compounds used in many industries to colour other materials. The demand for naturally synthesised pigments is increasing and their production can be incorporated into circular bioeconomy approaches. Natural pigments are produced by bacteria, cyanobacteria, microalgae, macroalgae, plants and animals. There is a huge unexplored biodiversity of prokaryotic cyanobacteria which are microscopic phototrophic microorganisms that have the ability to capture solar energy and CO2 and use it to synthesise a diverse range of sugars, lipids, amino acids and biochemicals including pigments. This makes them attractive for the sustainable production of a wide range of high-value products including industrial chemicals, pharmaceuticals, nutraceuticals and animal-feed supplements. The advantages of cyanobacteria production platforms include comparatively high growth rates, their ability to use freshwater, seawater or brackish water and the ability to cultivate them on non-arable land. The pigments derived from cyanobacteria and microalgae include chlorophylls, carotenoids and phycobiliproteins that have useful properties for advanced technical and commercial products. Development and optimisation of strain-specific pigment-based cultivation strategies support the development of economically feasible pigment biorefinery scenarios with enhanced pigment yields, quality and price. Thus, this chapter discusses the origin, properties, strain selection, production techniques and market opportunities of cyanobacterial pigments.
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Affiliation(s)
- Charu Deepika
- Institute of Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia
| | - Juliane Wolf
- Institute of Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia
| | - John Roles
- Institute of Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia
| | - Ian Ross
- Institute of Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia
| | - Ben Hankamer
- Institute of Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia.
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Helaly MN, El-Hoseiny HM, Elsheery NI, Kalaji HM, de los Santos-Villalobos S, Wróbel J, Hassan IF, Gaballah MS, Abdelrhman LA, Mira AM, Alam-Eldein SM. 5-Aminolevulinic Acid and 24-Epibrassinolide Improve the Drought Stress Resilience and Productivity of Banana Plants. PLANTS (BASEL, SWITZERLAND) 2022; 11:743. [PMID: 35336624 PMCID: PMC8949027 DOI: 10.3390/plants11060743] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 02/17/2022] [Accepted: 03/01/2022] [Indexed: 05/14/2023]
Abstract
Plant growth, development, and productivity are adversely affected under drought conditions. Previous findings indicated that 5-aminolevulinic acid (ALA) and 24-epibrassinolide (EBL) play an important role in the plant response to adverse environmental conditions. This study demonstrated the role of ALA and EBL on oxidative stress and photosynthetic capacity of drought-stressed 'Williams' banana grown under the Egyptian semi-arid conditions. Exogenous application of either ALA or EBL at concentrations of 15, 30, and 45 mg·L-1 significantly restored plant photosynthetic activity and increased productivity under reduced irrigation; this was equivalent to 75% of the plant's total water requirements. Both compounds significantly reduced drought-induced oxidative damages by increasing antioxidant enzyme activities (superoxide dismutase 'SOD', catalase 'CAT', and peroxidase 'POD') and preserving chloroplast structure. Lipid peroxidation, electrolyte loss and free non-radical H2O2 formation in the chloroplast were noticeably reduced compared to the control, but chlorophyll content and photosynthetic oxygen evolution were increased. Nutrient uptake, auxin and cytokinin levels were also improved with the reduced abscisic acid levels. The results indicated that ALA and EBL could reduce the accumulation of reactive oxygen species and maintain the stability of the chloroplast membrane structure under drought stress. This study suggests that the use of ALA or EBL at 30 mg·L-1 can promote the growth, productivity and fruit quality of drought-stressed banana plants.
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Affiliation(s)
- Mohamed N. Helaly
- Agricultural Botany Department, Faculty of Agriculture, Mansoura University, Mansoura 35516, Egypt;
| | - Hanan M. El-Hoseiny
- Horticulture Department, Faculty of Desert and Environmental Agriculture, Matrouh University, Fouka 51511, Egypt;
| | - Nabil I. Elsheery
- Agricultural Botany Department, Faculty of Agriculture, Tanta University, Tanta 31527, Egypt;
| | - Hazem M. Kalaji
- Department of Plant Physiology, Institute of Biology, Warsaw University of Life Sciences SGGW, 02-776 Warsaw, Poland; or
- Institute of Technology and Life Sciences, National Research Institute, Falenty, Al.Hrabska 3, 05-090 Pruszków, Poland
| | | | - Jacek Wróbel
- Department of Bioengineering, West Pomeranian University of Technology, 71-434 Szczecin, Poland;
| | - Islam F. Hassan
- Water Relations and Field Irrigation Department, Agricultural and Biological Research Institute, National Research Center, Giza 12622, Egypt; (I.F.H.); (M.S.G.)
| | - Maybelle S. Gaballah
- Water Relations and Field Irrigation Department, Agricultural and Biological Research Institute, National Research Center, Giza 12622, Egypt; (I.F.H.); (M.S.G.)
| | - Lamyaa A. Abdelrhman
- Soil, Water and Environment Research Institute (SWERI), Agricultural Research Center, Giza 12619, Egypt;
| | - Amany M. Mira
- Department of Horticulture, Faculty of Agriculture, Tanta University, Tanta 31527, Egypt;
| | - Shamel M. Alam-Eldein
- Department of Horticulture, Faculty of Agriculture, Tanta University, Tanta 31527, Egypt;
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Banu S, Yadav PP. Chlorophyll: the ubiquitous photocatalyst of nature and its potential as an organo-photocatalyst in organic syntheses. Org Biomol Chem 2022; 20:8584-8598. [DOI: 10.1039/d2ob01473d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The emergence of chlorophyll, the principal photoacceptor of green plants, as an organo-photocatalyst.
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Affiliation(s)
- Saira Banu
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow-226031, India
- Academy of Scientific & Innovative Research, Ghaziabad-201002, India
| | - Prem P. Yadav
- Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow-226031, India
- Academy of Scientific & Innovative Research, Ghaziabad-201002, India
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IDPM: an online database for ion distribution in protein molecules. BMC Bioinformatics 2018; 19:102. [PMID: 29548284 PMCID: PMC5857119 DOI: 10.1186/s12859-018-2110-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 03/06/2018] [Indexed: 11/21/2022] Open
Abstract
Background Interactions between ions and proteins have been extensively studied, yet most of the studies focus on the ion binding site. The binding mechanism for many ion binding sites can be clearly described from high resolution structures. Although knowledge accumulated on a case-by-case basis is valuable, it is also important to study the ion-protein interaction statistically. From experimentally determined structures, it is possible to examine the ion distribution around each amino acid. Such distributions can reveal relation between ions and amino acids, so it is desirable to carry out a systematic survey of ‘ion-amino acid’ pairing interaction and share the information with a publicly available database. Results The survey in the Protein Data Bank (PDB) revealed that approximately 40% of molecules records contain at least one ion. To reduce the bias resulted from protein redundancy, the statistics were extracted from a non-redundant dataset by excluding the proteins with similar sequences. Based on the structures of protein molecules and the location of ions, the statistical distributions of ions around each proteinogenic amino acid type were investigated and further summarized in a database. To systematically quantify the interactions between ions and each amino acid, the positions of ions were mapped to the coordinate system centered at each neighboring amino acid. It was found that the distribution of ions follows the expected rules governed by the physicochemical interactions in general. Large variations were observed, reflecting the preference in ‘ion-amino acid’ interactions. The analysis program is written in the Python programming language. The statistical results and program are available from the online database: ion distribution in protein molecules (IDPM) at http://liulab.csrc.ac.cn/idpm/. Conclusion The spatial distribution of ions around amino acids is documented and analyzed. The statistics can be useful for identifying ion types for a given site in biomolecules, and can be potentially used in ion position prediction for given structures. Electronic supplementary material The online version of this article (10.1186/s12859-018-2110-9) contains supplementary material, which is available to authorized users.
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Nowicka B, Kruk J. Powered by light: Phototrophy and photosynthesis in prokaryotes and its evolution. Microbiol Res 2016; 186-187:99-118. [PMID: 27242148 DOI: 10.1016/j.micres.2016.04.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 02/12/2016] [Accepted: 04/01/2016] [Indexed: 11/29/2022]
Abstract
Photosynthesis is a complex metabolic process enabling photosynthetic organisms to use solar energy for the reduction of carbon dioxide into biomass. This ancient pathway has revolutionized life on Earth. The most important event was the development of oxygenic photosynthesis. It had a tremendous impact on the Earth's geochemistry and the evolution of living beings, as the rise of atmospheric molecular oxygen enabled the development of a highly efficient aerobic metabolism, which later led to the evolution of complex multicellular organisms. The mechanism of photosynthesis has been the subject of intensive research and a great body of data has been accumulated. However, the evolution of this process is not fully understood, and the development of photosynthesis in prokaryota in particular remains an unresolved question. This review is devoted to the occurrence and main features of phototrophy and photosynthesis in prokaryotes. Hypotheses concerning the origin and spread of photosynthetic traits in bacteria are also discussed.
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Affiliation(s)
- Beatrycze Nowicka
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
| | - Jerzy Kruk
- Department of Plant Physiology and Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland.
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9
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Neupane B, Dang NC, Acharya K, Reppert M, Zazubovich V, Picorel R, Seibert M, Jankowiak R. Insight into the electronic structure of the CP47 antenna protein complex of photosystem II: hole burning and fluorescence study. J Am Chem Soc 2010; 132:4214-29. [PMID: 20218564 DOI: 10.1021/ja908510w] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report low temperature (T) optical spectra of the isolated CP47 antenna complex from Photosystem II (PSII) with a low-T fluorescence emission maximum near 695 nm and not, as previously reported, at 690-693 nm. The latter emission is suggested to result from three distinct bands: a lowest-state emission band near 695 nm (labeled F1) originating from the lowest-energy excitonic state A1 of intact complexes (located near 693 nm and characterized by very weak oscillator strength) as well as emission peaks near 691 nm (FT1) and 685 nm (FT2) originating from subpopulations of partly destabilized complexes. The observation of the F1 emission is in excellent agreement with the 695 nm emission observed in intact PSII cores and thylakoid membranes. We argue that the band near 684 nm previously observed in singlet-minus-triplet spectra originates from a subpopulation of partially destabilized complexes with lowest-energy traps located near 684 nm in absorption (referred to as AT2) giving rise to FT2 emission. It is demonstrated that varying contributions from the F1, FT1, and FT2 emission bands led to different maxima of fluorescence spectra reported in the literature. The fluorescence spectra are consistent with the zero-phonon hole action spectra obtained in absorption mode, the profiles of the nonresonantly burned holes as a function of fluence, as well as the fluorescence line-narrowed spectra obtained for the Q(y) band. The lowest Q(y) state in absorption band (A1) is characterized by an electron-phonon coupling with the Huang-Rhys factor S of approximately 1 and an inhomogeneous width of approximately 180 cm(-1). The mean phonon frequency of the A1 band is 20 cm(-1). In contrast to previous observations, intact isolated CP47 reveals negligible contribution from the triplet-bottleneck hole, i.e., the AT2 trap. It has been shown that Chls in intact CP47 are connected via efficient excitation energy transfer to the A1 trap near 693 nm and that the position of the fluorescence maximum depends on the burn fluence. That is, the 695 nm fluorescence maximum shifts blue with increasing fluence, in agreement with nonresonant hole burned spectra. The above findings provide important constraints and parameters for future excitonic calculations, which in turn should offer new insight into the excitonic structure and composition of low-energy absorption traps.
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Affiliation(s)
- Bhanu Neupane
- Department of Chemistry, Kansas State University, Manhattan, Kansas 66506, USA
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Abstract
Photosynthesis is the major process that converts solar energy into chemical energy on Earth. Two and a half billion years ago, the ancestors of cyanobacteria were able to use water as electron source for the photosynthetic process, thereby evolving oxygen and changing the atmosphere of our planet Earth. Two large membrane protein complexes, Photosystems I and II, catalyze the primary step in this energy conversion, the light-induced charge separation across the photosynthetic membrane. This chapter describes and compares the structure of two Photosystems and discusses their function in respect to the mechanism of light harvesting, electron transfer and water splitting.
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Affiliation(s)
- Petra Fromme
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287-1604, USA.
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11
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Burda K. Dynamics of electron transfer in photosystem II. Cell Biochem Biophys 2007; 47:271-84. [PMID: 17652775 DOI: 10.1007/s12013-007-0011-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 11/26/2022]
Abstract
Photosystem II, being a constituent of light driven photosynthetic apparatus, is a highly organized pigment-protein-lipid complex. The arrangement of PSII active redox cofactors insures efficiency of electron transfer within it. Donation of electrons extracted from water by the oxygen evolving complex to plastoquinones requires an additional activation energy. In this paper we present theoretical discussion of the anharmonic fluctuations of the protein-lipid matrix of PSII and an experimental evidence showing that the fluctuations are responsible for coupling of its donor and acceptor side. We argue that the fast collective motions liberated at temperatures higher that 200 K are crucial for the two final steps of the water splitting cycle and that one can distinguish three different dynamic regimes of PSII action which are controlled by the timescales of forward electron transfer, which vary with temperature. The three regimes of the dynamical behavior are related to different spatial domains of PSII.
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Affiliation(s)
- Kvetoslava Burda
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Kraków, Poland.
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Alstrum-Acevedo JH, Brennaman MK, Meyer TJ. Chemical approaches to artificial photosynthesis. 2. Inorg Chem 2006; 44:6802-27. [PMID: 16180838 DOI: 10.1021/ic050904r] [Citation(s) in RCA: 715] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The goal of artificial photosynthesis is to use the energy of the sun to make high-energy chemicals for energy production. One approach, described here, is to use light absorption and excited-state electron transfer to create oxidative and reductive equivalents for driving relevant fuel-forming half-reactions such as the oxidation of water to O2 and its reduction to H2. In this "integrated modular assembly" approach, separate components for light absorption, energy transfer, and long-range electron transfer by use of free-energy gradients are integrated with oxidative and reductive catalysts into single molecular assemblies or on separate electrodes in photelectrochemical cells. Derivatized porphyrins and metalloporphyrins and metal polypyridyl complexes have been most commonly used in these assemblies, with the latter the focus of the current account. The underlying physical principles--light absorption, energy transfer, radiative and nonradiative excited-state decay, electron transfer, proton-coupled electron transfer, and catalysis--are outlined with an eye toward their roles in molecular assemblies for energy conversion. Synthetic approaches based on sequential covalent bond formation, derivatization of preformed polymers, and stepwise polypeptide synthesis have been used to prepare molecular assemblies. A higher level hierarchial "assembly of assemblies" strategy is required for a working device, and progress has been made for metal polypyridyl complex assemblies based on sol-gels, electropolymerized thin films, and chemical adsorption to thin films of metal oxide nanoparticles.
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Affiliation(s)
- James H Alstrum-Acevedo
- Department of Chemistry, University of North Carolina at Chapel Hill, CB #3290, 27599-3290, USA
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Aldridge WS, Hornstein BJ, Serron S, Dattelbaum DM, Schoonover JR, Meyer TJ. Synthesis and Characterization of Oligoproline-Based Molecular Assemblies for Light Harvesting. J Org Chem 2006; 71:5186-90. [PMID: 16808505 DOI: 10.1021/jo0603936] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Helical oligoproline arrays provide a structurally well-defined environment for building photochemical energy conversion assemblies. The use of solid-phase peptide synthesis (SPPS) to prepare four such arrays, consisting of 16, 17, 18, and 19 amino acid residues, is described here. Each array contains the chromophore [Rub'(2)m](PF(6))(2) (b' = 4,4'-diethylamidocarbonyl-2,2'-bipyridine; m = 4-methyl-2,2'-dipyridine-4'-carboxylic acid) and the electron transfer donor PTZ (phenothiazine). The arrays differ systematically in the distance between the redox-active metal complex and PTZ sites. They have been used in photophysical studies to provide insight into the distance dependence of electron transfer. (J. Am. Chem. Soc. 2004, 126, 14506-14514). This work describes the synthesis, purification, and characterization of the oligoproline arrays, including a general procedure for the synthesis of related arrays.
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Affiliation(s)
- W Steven Aldridge
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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Fromme P, Yu H, DeRuyter YS, Jolley C, Chauhan DK, Melkozernov A, Grotjohann I. Structure of photosystems I and II. CR CHIM 2006. [DOI: 10.1016/j.crci.2005.06.039] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Grotjohann I, Fromme P. Structure of cyanobacterial photosystem I. PHOTOSYNTHESIS RESEARCH 2005; 85:51-72. [PMID: 15977059 DOI: 10.1007/s11120-005-1440-4] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2004] [Accepted: 01/28/2005] [Indexed: 05/03/2023]
Abstract
Photosystem I is one of the most fascinating membrane protein complexes for which a structure has been determined. It functions as a bio-solar energy converter, catalyzing one of the first steps of oxygenic photosynthesis. It captures the light of the sun by means of a large antenna system, consisting of chlorophylls and carotenoids, and transfers the energy to the center of the complex, driving the transmembrane electron transfer from plastoquinone to ferredoxin. Cyanobacterial Photosystem I is a trimer consisting of 36 proteins to which 381 cofactors are non-covalently attached. This review discusses the complex function of Photosystem I based on the structure of the complex at 2.5 A resolution as well as spectroscopic and biochemical data.
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