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Kang L, Li Q, Jing Y, Ren F, Li E, Zeng X, Xu Y, Wang D, Wang Q, Sun G, Wei L, Diao Y. Auricularia auricula Anionic Polysaccharide Nanoparticles for Gastrointestinal Delivery of Pinus koraiensis Polyphenol Used in Bone Protection under Weightlessness. Molecules 2024; 29:245. [PMID: 38202827 PMCID: PMC10780251 DOI: 10.3390/molecules29010245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2023] [Revised: 12/23/2023] [Accepted: 12/29/2023] [Indexed: 01/12/2024] Open
Abstract
Auricularia auricula polysaccharides used in Pinus koraiensis polyphenol encapsulation and delivery under weightlessness are rarely reported. In this study, an anionic polysaccharide fragment named AAP Iα with a molecular weight of 133.304 kDa was isolated and purified to construct a polyphenol encapsulation system. Nanoparticles named NPs-PP loaded with a rough surface for Pinus koraiensis polyphenol (PP) delivery were fabricated by AAP Iα and ε-poly-L-lysine (ε-PL). SEM and the DLS tracking method were used to observe continuous changes in AAP Iα, ε-PL and PP on the nanoparticles' rough surface assembly, as well as the dispersion and stability. Hydrophilic, monodisperse and highly negative charged nanoparticles can be formed at AAP Iα 0.8 mg/mL, ε-PL 20 μg/mL and PP 80 μg/mL. FT-IR was used to determine their electrostatic interactions. Release kinetic studies showed that nanoparticles had an ideal gastrointestinal delivery effect. NPs-PP loaded were assembled through electrostatic interactions between polyelectrolytes after hydrogen bonding formation in PP-AAP Iα and PP-ε-PL, respectively. Colon adhesion properties and PP delivery in vivo of nanoparticles showed that NPs-PP loaded had high adhesion efficiency to the colonic mucosa under simulated microgravity and could enhance PP bioavailability. These results suggest that AAP Iα can be used in PP encapsulation and delivery under microgravity in astronaut food additives.
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Affiliation(s)
- Li Kang
- College of Life Science, China West Normal University, Nanchong 637009, China (Y.J.); (F.R.)
| | - Qiao Li
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150000, China (E.L.)
| | - Yonghui Jing
- College of Life Science, China West Normal University, Nanchong 637009, China (Y.J.); (F.R.)
| | - Feiyan Ren
- College of Life Science, China West Normal University, Nanchong 637009, China (Y.J.); (F.R.)
| | - Erzhuo Li
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150000, China (E.L.)
| | - Xiangyin Zeng
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150000, China (E.L.)
| | - Yier Xu
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150000, China (E.L.)
| | - Dongwei Wang
- College of Life Science, China West Normal University, Nanchong 637009, China (Y.J.); (F.R.)
| | - Qiang Wang
- College of Life Science, China West Normal University, Nanchong 637009, China (Y.J.); (F.R.)
| | - Guicai Sun
- The First Affiliated Hospital of Nanchang University, Nanchang 330000, China
| | - Lijun Wei
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150000, China (E.L.)
| | - Yan Diao
- College of Life Science, China West Normal University, Nanchong 637009, China (Y.J.); (F.R.)
- Collaboration Innovation Center for Tissue Repair Material Engineering Technology, China West Normal University, Nanchong 637002, China
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Removal and Mechanism of Cadmium, Lead and Copper in Water by Functional Modification of Silkworm Excrement Biochar. Polymers (Basel) 2022; 14:polym14142889. [PMID: 35890663 PMCID: PMC9323519 DOI: 10.3390/polym14142889] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Revised: 07/05/2022] [Accepted: 07/06/2022] [Indexed: 02/04/2023] Open
Abstract
A new type of biochar, called GBC, was prepared from silkworm excrement, and then modified by chitosan combined with pyromellitic dianhydride. The removal of mono-metal and polymetals (Pb, Cd and Cu) from an aqueous solution by GBC was investigated in this research. Compared to unmodified biochar, the removal rate of Pb and Cd by GBC was about 12% higher, while that of Cu was about 94.6% higher. It also shows the types of functional groups in biochar have a great impact on their adsorption. The removal of Pb is mainly involved in the N-C=O functional group, the removal of Cd is mainly involved in N-containing functional group and C=C bond, and that of Cu is mainly involved in N-containing functional group, carboxyl group, hydroxyl group, and a carbonyl group. Five adsorption–desorption cycles of GBC were carried out, and it was found that the adsorption capacities of GBC for Pb, Cd and Cu decreased by 7.28%, 10.78% and 6.07%, respectively, indicating that GBC had a good renewable performance. The adsorption capacity of GBC for Cu in different water samples is between 89.62 and 93.47 mg·g−1, indicating that GBC has great application potential for the removal of Cu in wastewater.
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Xu T, Zhu R, Shang H, Xia Y, Liu X, Zhang L. Photochemical behavior of ferrihydrite-oxalate system: Interfacial reaction mechanism and charge transfer process. WATER RESEARCH 2019; 159:10-19. [PMID: 31075500 DOI: 10.1016/j.watres.2019.04.055] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 04/25/2019] [Accepted: 04/28/2019] [Indexed: 06/09/2023]
Abstract
Heterogeneous photochemical reactions associated with natural iron (hydr)oxides and oxalic acid have attracted a great deal of scientific attention in the application of organic pollutants degradation. However, the reaction mechanism is still unclear due to the complicated iron cycles and reactive oxygen species (ROS) generation. In this study, the in situ attenuated total reflectance-Fourier transform infrared spectroscopy was implemented to investigate the adsorption process and photochemical behavior of oxalic acid on the surface of ferrihydrite. A comprehensive reaction mechanism from the perspective of charge transfer process, including homogeneous-heterogeneous iron cycling and ROS generation, was illustrated in detail. We found that oxalic acid was first adsorbed on the surface of ferrihydrite with a mononuclear bidentate binding geometry. Interestingly, this mononuclear bidentate complex on the surface of ferrihydrite was stable under visible light irradiation. Subsequently, the whole complex departed from ferrihydrite surface through non-reduction dissolution with the form of Fe(C2O4)+. In the solution, the Fe(C2O4)+ complexes would quickly convert to Fe(C2O4)2- complexes. Under visible light irradiation, the electrons generated from the photolysis of Fe(C2O4)2- complex reacted with O2 to form O2•-/•OOH. Meanwhile, Fe(III) was reduced to Fe(II). Finally, the produced O2•-/•OOH could react with Fe(II) through a one-step way to generate •OH, which possessed higher •OH formation efficiency than that through the two-step way of H2O2 as the intermediates. This study helps us with understanding of in-situ photochemical reaction mechanism of ferrihydrite-oxalic acid system, and also provides guidance to effectively utilize widespread iron (hydr)oxides and organic acids in natural environment to develop engineered systems for water treatment.
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Affiliation(s)
- Tianyuan Xu
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan, 430079, People's Republic of China
| | - Runliang Zhu
- Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, 511 Kehua Street, Guangzhou, 510640, People's Republic of China
| | - Huan Shang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan, 430079, People's Republic of China
| | - Yabei Xia
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan, 430079, People's Republic of China
| | - Xiao Liu
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan, 430079, People's Republic of China.
| | - Lizhi Zhang
- Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan, 430079, People's Republic of China
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Maréchal A, Hartley AM, Warelow TP, Meunier B, Rich PR. Comparison of redox and ligand binding behaviour of yeast and bovine cytochrome c oxidases using FTIR spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:705-711. [PMID: 29852141 PMCID: PMC6094048 DOI: 10.1016/j.bbabio.2018.05.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 05/18/2018] [Accepted: 05/24/2018] [Indexed: 11/20/2022]
Abstract
Redox and CO photolysis FTIR spectra of yeast cytochrome c oxidase WT and mutants are compared to those from bovine and P. denitrificans CcOs in order to establish common functional features. All display changes that can be assigned to their E242 (bovine numbering) equivalent and to weakly H-bonded water molecules. The additional redox-sensitive band reported at 1736 cm−1 in bovine CcO and previously assigned to D51 is absent from yeast CcO and couldn't be restored by introduction of a D residue at the equivalent position of the yeast protein. Redox spectra of yeast CcO also show much smaller changes in the amide I region, which may relate to structural differences in the region around D51 and the subunit I/II interface. Redox-induced FTIR difference spectra of WT and mutant yeast CcO are presented. Functionally-relevant features are compared with other A1-type haem copper oxidases. On oxidoreduction, all show perturbations of bovine residue E242 Introduction of bovine D51 in yeast doesn't result in an additional IR redox band. On photolysis of the FR-CO form all show perturbations of E242 and water molecules
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Affiliation(s)
- Amandine Maréchal
- Department of Biological Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK; Department of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK.
| | - Andrew M Hartley
- Department of Biological Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
| | - Thomas P Warelow
- Department of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Brigitte Meunier
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette, France
| | - Peter R Rich
- Department of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK.
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Deng J, Liu Y, Liu S, Zeng G, Tan X, Huang B, Tang X, Wang S, Hua Q, Yan Z. Competitive adsorption of Pb(II), Cd(II) and Cu(II) onto chitosan-pyromellitic dianhydride modified biochar. J Colloid Interface Sci 2017; 506:355-364. [DOI: 10.1016/j.jcis.2017.07.069] [Citation(s) in RCA: 208] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Revised: 07/16/2017] [Accepted: 07/17/2017] [Indexed: 10/19/2022]
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ns-μs Time-Resolved Step-Scan FTIR of ba₃ Oxidoreductase from Thermus thermophilus: Protonic Connectivity of w941-w946-w927. Int J Mol Sci 2016; 17:ijms17101657. [PMID: 27690021 PMCID: PMC5085690 DOI: 10.3390/ijms17101657] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 09/13/2016] [Accepted: 09/21/2016] [Indexed: 02/07/2023] Open
Abstract
Time-resolved step-scan FTIR spectroscopy has been employed to probe the dynamics of the ba3 oxidoreductase from Thermus thermophilus in the ns-μs time range and in the pH/pD 6–9 range. The data revealed a pH/pD sensitivity of the D372 residue and of the ring-A propionate of heme a3. Based on the observed transient changes a model in which the protonic connectivity of w941-w946-927 to the D372 and the ring-A propionate of heme a3 is described.
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Kriegel S, Srour B, Steimle S, Friedrich T, Hellwig P. Involvement of Acidic Amino Acid Residues in Zn2+Binding to Respiratory Complex I. Chembiochem 2015; 16:2080-5. [DOI: 10.1002/cbic.201500273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Indexed: 12/13/2022]
Affiliation(s)
- Sébastien Kriegel
- Laboratoire de Bioelectrochimie et Spectroscopie; UMR 7140; Chimie de la Matière Complexe; Université de Strasbourg; CNRS; 1 rue Blaise Pascal 67070 Strasbourg France
- Université Paris Diderot; Sorbonne Paris Cité; Laboratoire d'Electrochimie Moléculaire; Unité Mixte de Recherche Université-; CNRS No. 7591; Bâtiment Lavoisier 15 rue Jean de Baïf 75205 Paris Cedex 13 France
| | - Batoul Srour
- Laboratoire de Bioelectrochimie et Spectroscopie; UMR 7140; Chimie de la Matière Complexe; Université de Strasbourg; CNRS; 1 rue Blaise Pascal 67070 Strasbourg France
| | - Stefan Steimle
- Albert-Ludwigs-Universität Freiburg; Institut für Biochemie; Albertstrasse 21 79104 Freiburg Germany
| | - Thorsten Friedrich
- Albert-Ludwigs-Universität Freiburg; Institut für Biochemie; Albertstrasse 21 79104 Freiburg Germany
| | - Petra Hellwig
- Laboratoire de Bioelectrochimie et Spectroscopie; UMR 7140; Chimie de la Matière Complexe; Université de Strasbourg; CNRS; 1 rue Blaise Pascal 67070 Strasbourg France
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Nakashima S, Ogura T, Kitagawa T. Infrared and Raman spectroscopic investigation of the reaction mechanism of cytochrome c oxidase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1847:86-97. [PMID: 25135480 DOI: 10.1016/j.bbabio.2014.08.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 07/07/2014] [Accepted: 08/11/2014] [Indexed: 10/24/2022]
Abstract
Recent progress in studies on the proton-pumping and O₂reduction mechanisms of cytochrome c oxidase (CcO) elucidated by infrared (IR) and resonance Raman (rR) spectroscopy, is reviewed. CcO is the terminal enzyme of the respiratory chain and its O₂reduction reaction is coupled with H⁺ pumping activity across the inner mitochondrial membrane. The former is catalyzed by heme a3 and its mechanism has been determined using a rR technique, while the latter used the protein moiety and has been investigated with an IR technique. The number of H⁺ relative to e⁻ transferred in the reaction is 1:1, and their coupling is presumably performed by heme a and nearby residues. To perform this function, different parts of the protein need to cooperate with each other spontaneously and sequentially. It is the purpose of this article to describe the structural details on the coupling on the basis of the vibrational spectra of certain specified residues and chromophores involved in the reaction. Recent developments in time-resolved IR and Raman technology concomitant with protein manipulation methods have yielded profound insights into such structural changes. In particular, the new IR techniques that yielded the breakthrough are reviewed and assessed in detail. This article is part of a Special Issue entitled: Vibrational spectroscopies and bioenergetic systems.
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Affiliation(s)
- Satoru Nakashima
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, RSC-UH Leading Program Center, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Takashi Ogura
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, RSC-UH Leading Program Center, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan; Department of Life Science, Graduate School of Life Science, University of Hyogo, RSC-UH Leading Program Center, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Teizo Kitagawa
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, RSC-UH Leading Program Center, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan.
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IR signatures of the metal centres of bovine cytochrome c oxidase: assignments and redox-linkage. Biochem Soc Trans 2014; 41:1242-8. [PMID: 24059514 DOI: 10.1042/bst20130087] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Assignments of IR bands of reduced minus oxidized IR difference spectra of bovine and related cytochrome c oxidases are reviewed and their linkages to specific metal centres are assessed. To aid this, redox-poised difference spectra in the presence of cyanide or carbon monoxide are presented. These ligands fix the redox states of either haem a3 alone or haem a3 and CuB respectively, while allowing redox cycling of the remaining centres.
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Cerda JF, Malloy MC, Werkheiser BO, Stockhausen AT, Gallagher MF, Lawler AC. Evaluation of Heme Peripheral Group Interactions in Extremely Low-Dielectric Constant Media and Their Contributions to the Heme Reduction Potential. Inorg Chem 2013; 53:182-8. [DOI: 10.1021/ic401986n] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Jose F. Cerda
- Department of Chemistry, Saint Joseph’s University, Philadelphia, Pennsylvania 19131, United States
| | - Mary C. Malloy
- Department of Chemistry, Saint Joseph’s University, Philadelphia, Pennsylvania 19131, United States
| | - Brady O. Werkheiser
- Department of Chemistry, Saint Joseph’s University, Philadelphia, Pennsylvania 19131, United States
| | - Alaina T. Stockhausen
- Department of Chemistry, Saint Joseph’s University, Philadelphia, Pennsylvania 19131, United States
| | - Michael F. Gallagher
- Department of Chemistry, Saint Joseph’s University, Philadelphia, Pennsylvania 19131, United States
| | - Andrew C. Lawler
- Department of Chemistry, Saint Joseph’s University, Philadelphia, Pennsylvania 19131, United States
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Maréchal A, Iwaki M, Rich PR. Structural Changes in Cytochrome c Oxidase Induced by Binding of Sodium and Calcium Ions: An ATR-FTIR Study. J Am Chem Soc 2013; 135:5802-7. [DOI: 10.1021/ja4005706] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Amandine Maréchal
- Glynn Laboratory of
Bioenergetics,
Institute of Structural and Molecular Biology, University College London, Gower Street, London, WC1E 6BT, United
Kingdom
| | - Masayo Iwaki
- Glynn Laboratory of
Bioenergetics,
Institute of Structural and Molecular Biology, University College London, Gower Street, London, WC1E 6BT, United
Kingdom
| | - Peter R. Rich
- Glynn Laboratory of
Bioenergetics,
Institute of Structural and Molecular Biology, University College London, Gower Street, London, WC1E 6BT, United
Kingdom
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Assignment of the CO-sensitive carboxyl group in mitochondrial forms of cytochrome c oxidase using yeast mutants. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1817:1921-4. [PMID: 22503843 DOI: 10.1016/j.bbabio.2012.03.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Revised: 03/22/2012] [Accepted: 03/29/2012] [Indexed: 11/21/2022]
Abstract
Point mutations of E243D and I67N were introduced into subunit I of a 6histidine-tagged (6H-WT) form of yeast Saccharomyces cerevisiae mitochondrial cytochrome c oxidase. The two mutants (6H-E243D(I) and 6H-I67N(I)) were purified and showed ≈50 and 10% of the 6H-WT turnover number. Light-induced CO photolysis FTIR difference spectra of the 6H-WT showed a peak/trough at 1749/1740cm(-1), as seen in bovine CcO, which downshifted by 7cm(-1) in D(2)O. The bands shifted to 1736/1762cm(-1) in 6H-E243D(I), establishing that the carboxyl group affected by CO binding in mitochondrial CcOs is E243. In 6H-I67N(I), the trough at 1740cm(-1) was shifted to 1743cm(-1) and its accompanying peak intensity was greatly reduced. This confirms that the I67N mutation interferes with conformational alterations around E243. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012).
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Water molecule reorganization in cytochrome c oxidase revealed by FTIR spectroscopy. Proc Natl Acad Sci U S A 2011; 108:8634-8. [PMID: 21543712 DOI: 10.1073/pnas.1019419108] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Although internal electron transfer and oxygen reduction chemistry in cytochrome c oxidase are fairly well understood, the associated groups and pathways that couple these processes to gated proton translocation across the membrane remain unclear. Several possible pathways have been identified from crystallographic structural models; these involve hydrophilic residues in combination with structured waters that might reorganize to form transient proton transfer pathways during the catalytic cycle. To date, however, comparisons of atomic structures of different oxidases in different redox or ligation states have not provided a consistent answer as to which pathways are operative or the details of their dynamic changes during catalysis. In order to provide an experimental means to address this issue, FTIR spectroscopy in the 3,560-3,800 cm(-1) range has been used to detect weakly H-bonded water molecules in bovine cytochrome c oxidase that might change during catalysis. Full redox spectra exhibited at least four signals at 3,674(+), 3,638(+), 3,620(-), and 3,607(+) cm(-1). A more complex set of signals was observed in spectra of photolysis of the ferrous-CO compound, a reaction that mimics the catalytic oxygen binding step, and their D(2)O and H(2)(18)O sensitivities confirmed that they arose from water molecule rearrangements. Fitting with Gaussian components indicated the involvement of up to eight waters in the photolysis transition. Similar signals were also observed in photolysis spectra of the ferrous-CO compound of bacterial CcO from Paracoccus denitrificans. Such water changes are discussed in relation to roles in hydrophilic channels and proton/electron coupling mechanism.
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