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Shimada A, Hara F, Shinzawa-Itoh K, Kanehisa N, Yamashita E, Muramoto K, Tsukihara T, Yoshikawa S. Critical roles of the Cu B site in efficient proton pumping as revealed by crystal structures of mammalian cytochrome c oxidase catalytic intermediates. J Biol Chem 2021; 297:100967. [PMID: 34274318 PMCID: PMC8390519 DOI: 10.1016/j.jbc.2021.100967] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 07/07/2021] [Accepted: 07/12/2021] [Indexed: 11/15/2022] Open
Abstract
Mammalian cytochrome c oxidase (CcO) reduces O2 to water in a bimetallic site including Fea3 and CuB giving intermediate molecules, termed A-, P-, F-, O-, E-, and R-forms. From the P-form on, each reaction step is driven by single-electron donations from cytochrome c coupled with the pumping of a single proton through the H-pathway, a proton-conducting pathway composed of a hydrogen-bond network and a water channel. The proton-gradient formed is utilized for ATP production by F-ATPase. For elucidation of the proton pumping mechanism, crystal structural determination of these intermediate forms is necessary. Here we report X-ray crystallographic analysis at ∼1.8 Å resolution of fully reduced CcO crystals treated with O2 for three different time periods. Our disentanglement of intermediate forms from crystals that were composed of multiple forms determined that these three crystallographic data sets contained ∼45% of the O-form structure, ∼45% of the E-form structure, and ∼20% of an oxymyoglobin-type structure consistent with the A-form, respectively. The O- and E-forms exhibit an unusually long CuB2+-OH- distance and CuB1+-H2O structure keeping Fea33+-OH- state, respectively, suggesting that the O- and E-forms have high electron affinities that cause the O→E and E→R transitions to be essentially irreversible and thus enable tightly coupled proton pumping. The water channel of the H-pathway is closed in the O- and E-forms and partially open in the R-form. These structures, together with those of the recently reported P- and F-forms, indicate that closure of the H-pathway water channel avoids back-leaking of protons for facilitating the effective proton pumping.
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Affiliation(s)
- Atsuhiro Shimada
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, kamigori, Akoh, Hyogo, Japan
| | - Fumiyoshi Hara
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, kamigori, Akoh, Hyogo, Japan
| | - Kyoko Shinzawa-Itoh
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, kamigori, Akoh, Hyogo, Japan; Department of Life Science, Graduate School of Life Science, University of Hyogo, kamigori, Akoh, Hyogo, Japan
| | - Nobuko Kanehisa
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka, Japan
| | - Eiki Yamashita
- Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Kazumasa Muramoto
- Department of Life Science, Graduate School of Life Science, University of Hyogo, kamigori, Akoh, Hyogo, Japan.
| | - Tomitake Tsukihara
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, kamigori, Akoh, Hyogo, Japan; Institute for Protein Research, Osaka University, Suita, Osaka, Japan.
| | - Shinya Yoshikawa
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, kamigori, Akoh, Hyogo, Japan; Department of Life Science, Graduate School of Life Science, University of Hyogo, kamigori, Akoh, Hyogo, Japan.
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Shimada A, Etoh Y, Kitoh-Fujisawa R, Sasaki A, Shinzawa-Itoh K, Hiromoto T, Yamashita E, Muramoto K, Tsukihara T, Yoshikawa S. X-ray structures of catalytic intermediates of cytochrome c oxidase provide insights into its O 2 activation and unidirectional proton-pump mechanisms. J Biol Chem 2020; 295:5818-5833. [PMID: 32165497 PMCID: PMC7186171 DOI: 10.1074/jbc.ra119.009596] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 03/09/2020] [Indexed: 01/07/2023] Open
Abstract
Cytochrome c oxidase (CcO) reduces O2 to water, coupled with a proton-pumping process. The structure of the O2-reduction site of CcO contains two reducing equivalents, Fe a32+ and CuB1+, and suggests that a peroxide-bound state (Fe a33+-O--O--CuB2+) rather than an O2-bound state (Fe a32+-O2) is the initial catalytic intermediate. Unexpectedly, however, resonance Raman spectroscopy results have shown that the initial intermediate is Fe a32+-O2, whereas Fe a33+-O--O--CuB2+ is undetectable. Based on X-ray structures of static noncatalytic CcO forms and mutation analyses for bovine CcO, a proton-pumping mechanism has been proposed. It involves a proton-conducting pathway (the H-pathway) comprising a tandem hydrogen-bond network and a water channel located between the N- and P-side surfaces. However, a system for unidirectional proton-transport has not been experimentally identified. Here, an essentially identical X-ray structure for the two catalytic intermediates (P and F) of bovine CcO was determined at 1.8 Å resolution. A 1.70 Å Fe-O distance of the ferryl center could best be described as Fe a34+ = O2-, not as Fe a34+-OH- The distance suggests an ∼800-cm-1 Raman stretching band. We found an interstitial water molecule that could trigger a rapid proton-coupled electron transfer from tyrosine-OH to the slowly forming Fe a33+-O--O--CuB2+ state, preventing its detection, consistent with the unexpected Raman results. The H-pathway structures of both intermediates indicated that during proton-pumping from the hydrogen-bond network to the P-side, a transmembrane helix closes the water channel connecting the N-side with the hydrogen-bond network, facilitating unidirectional proton-pumping during the P-to-F transition.
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Affiliation(s)
- Atsuhiro Shimada
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan
| | - Yuki Etoh
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan
| | - Rika Kitoh-Fujisawa
- Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan
| | - Ai Sasaki
- Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan
| | - Kyoko Shinzawa-Itoh
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan; Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan
| | - Takeshi Hiromoto
- Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan
| | - Eiki Yamashita
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Kazumasa Muramoto
- Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan.
| | - Tomitake Tsukihara
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan; Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Shinya Yoshikawa
- Picobiology Institute, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan; Department of Life Science, Graduate School of Life Science, University of Hyogo, 3-2-1 Koto, Kamigori, Akoh, Hyogo 678-1297, Japan.
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Tokiwa T, Shoji M, Sladek V, Shibata N, Higuchi Y, Kataoka K, Sakurai T, Shigeta Y, Misaizu F. Structural Changes of the Trinuclear Copper Center in Bilirubin Oxidase upon Reduction. Molecules 2018; 24:E76. [PMID: 30587809 DOI: 10.3390/molecules24010076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 12/17/2018] [Accepted: 12/20/2018] [Indexed: 11/16/2022] Open
Abstract
Geometric and electronic structure changes in the copper (Cu) centers in bilirubin oxidase (BOD) upon a four-electron reduction were investigated by quantum mechanics/molecular mechanics (QM/MM) calculations. For the QM region, the unrestricted density functional theory (UDFT) method was adopted for the open-shell system. We found new candidates of the native intermediate (NI, intermediate II) and the resting oxidized (RO) states, i.e., NIH+ and RO₀. Elongations of the Cu-Cu atomic distances for the trinuclear Cu center (TNC) and very small structural changes around the type I Cu (T1Cu) were calculated as the results of a four-electron reduction. The QM/MM optimized structures are in good agreement with recent high-resolution X-ray structures. As the structural change in the TNC upon reduction was revealed to be the change in the size of the triangle spanned by the three Cu atoms of TNC, we introduced a new index (l) to characterize the specific structural change. Not only the wild-type, but also the M467Q, which mutates the amino acid residue coordinating T1Cu, were precisely analyzed in terms of their molecular orbital levels, and the optimized redox potential of T1Cu was theoretically reconfirmed.
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Abstract
The KPC-2 carbapenemase enzyme is responsible for drug resistance in the majority of carbapenem-resistant gram-negative bacterial infections in the United States. A better understanding of what permits KPC-2 to hydrolyze carbapenem antibiotics and how this might be inhibited is thus of fundamental interest and great practical importance to development of better anti-infectives. By correlating molecular dynamics simulations with experimental enzyme kinetics, we have identified conformational changes that control KPC-2's ability to hydrolyze carbapenem antibiotics. Related beta-lactamase enzymes can interconvert between catalytically permissive and catalytically nonpermissive forms of an acylenzyme intermediate critical to drug hydrolysis. Using molecular dynamics simulations, we identify a similar equilibrium in KPC-2 and analyze the determinants of this conformational change. Because the conformational dynamics of KPC-2 are complex and sensitive to allosteric changes, we develop an information-theoretic approach to identify key determinants of this change. We measure unbiased estimators of the reaction coordinate between catalytically permissive and nonpermissive states, perform information-theoretic feature selection and, using restrained molecular dynamics simulations, validate the protein conformational changes predicted to control catalytically permissive geometry. We identify two binding-pocket residues that control the conformational transitions between catalytically active and inactive forms of KPC-2. Mutations to one of these residues, Trp105, lower the stability of the catalytically permissive state in simulations and have reduced experimental k cat values that show a strong linear correlation with the simulated catalytically permissive state lifetimes. This understanding can be leveraged to predict the drug resistance of further KPC-2 mutants and help design inhibitors to combat extreme drug resistance.
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Affiliation(s)
| | | | - Peter M. Kasson
- Laboratory of Molecular Biophysics, Science for Life Laboratory, Department of Cell and Molecular Biology, Uppsala University, Box 596, Uppsala 75124, Sweden
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Minges A, Höppner A, Groth G. Trapped intermediate state of plant pyruvate phosphate dikinase indicates substeps in catalytic swiveling domain mechanism. Protein Sci 2017; 26:1667-1673. [PMID: 28470715 PMCID: PMC5521584 DOI: 10.1002/pro.3184] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 04/26/2017] [Accepted: 04/26/2017] [Indexed: 12/18/2022]
Abstract
Pyruvate phosphate dikinase (PPDK) is an essential enzyme of both the C4 photosynthetic pathway and cellular energy metabolism of some bacteria and unicellular protists. In C4 plants, it catalyzes the ATP- and Pi -dependent formation of phosphoenolpyruvate (PEP) while in bacteria and protozoa the ATP-forming direction is used. PPDK is composed out of three distinct domains and exhibits one of the largest single domain movements known today during its catalytic cycle. However, little information about potential intermediate steps of this movement was available. A recent study resolved a discrete intermediate step of PPDK's swiveling movement, shedding light on the details of this intriguing mechanism. Here we present an additional structural intermediate that possibly represents another crucial step in the catalytic cycle of PPDK, providing means to get a more detailed understanding of PPDK's mode of function.
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Affiliation(s)
- Alexander Minges
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute of Biochemical Plant Physiology, Heinrich Heine University DüsseldorfDüsseldorf40204Germany
| | - Astrid Höppner
- X‐ray Facility and Crystal FarmHeinrich Heine University DüsseldorfDüsseldorf40204Germany
| | - Georg Groth
- Cluster of Excellence on Plant Sciences (CEPLAS), Institute of Biochemical Plant Physiology, Heinrich Heine University DüsseldorfDüsseldorf40204Germany
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Murakawa T, Hamaguchi A, Nakanishi S, Kataoka M, Nakai T, Kawano Y, Yamaguchi H, Hayashi H, Tanizawa K, Okajima T. Probing the Catalytic Mechanism of Copper Amine Oxidase from Arthrobacter globiformis with Halide Ions. J Biol Chem 2015; 290:23094-109. [PMID: 26269595 DOI: 10.1074/jbc.m115.662726] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Indexed: 11/06/2022] Open
Abstract
The catalytic reaction of copper amine oxidase proceeds through a ping-pong mechanism comprising two half-reactions. In the initial half-reaction, the substrate amine reduces the Tyr-derived cofactor, topa quinone (TPQ), to an aminoresorcinol form (TPQamr) that is in equilibrium with a semiquinone radical (TPQsq) via an intramolecular electron transfer to the active-site copper. We have analyzed this reductive half-reaction in crystals of the copper amine oxidase from Arthrobacter globiformis. Anerobic soaking of the crystals with an amine substrate shifted the equilibrium toward TPQsq in an "on-copper" conformation, in which the 4-OH group ligated axially to the copper center, which was probably reduced to Cu(I). When the crystals were soaked with substrate in the presence of halide ions, which act as uncompetitive and noncompetitive inhibitors with respect to the amine substrate and dioxygen, respectively, the equilibrium in the crystals shifted toward the "off-copper" conformation of TPQamr. The halide ion was bound to the axial position of the copper center, thereby preventing TPQamr from adopting the on-copper conformation. Furthermore, transient kinetic analyses in the presence of viscogen (glycerol) revealed that only the rate constant in the step of TPQamr/TPQsq interconversion is markedly affected by the viscogen, which probably perturbs the conformational change. These findings unequivocally demonstrate that TPQ undergoes large conformational changes during the reductive half-reaction.
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Affiliation(s)
- Takeshi Murakawa
- From the Department of Biochemistry, Osaka Medical College, Takatsuki, Osaka 569-8686, Japan
| | - Akio Hamaguchi
- the Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - Shota Nakanishi
- the Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - Misumi Kataoka
- the School of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan, the Advanced Photon Technology Division, RIKEN SPring-8 Center, Sayo-gun, Hyogo 679-5148, Japan
| | - Tadashi Nakai
- the Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - Yoshiaki Kawano
- the Advanced Photon Technology Division, RIKEN SPring-8 Center, Sayo-gun, Hyogo 679-5148, Japan
| | - Hiroshi Yamaguchi
- the School of Science and Technology, Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan, the Advanced Photon Technology Division, RIKEN SPring-8 Center, Sayo-gun, Hyogo 679-5148, Japan
| | - Hideyuki Hayashi
- the Department of Chemistry, Osaka Medical College, Takatsuki, Osaka 569-8686, Japan, and
| | - Katsuyuki Tanizawa
- the Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan, the Center of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, 783 71 Olomouc, Czech Republic
| | - Toshihide Okajima
- the Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan, the Department of Chemistry, Osaka Medical College, Takatsuki, Osaka 569-8686, Japan, and
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Abstract
Palladium(II) complexes with an auxiliary bidentate ligand featuring one C-Pd bond and a Pd-N-donor bond (palladacycles) have been shown to afford improved yields of homoallylic amines from a three-component coupling of boronic acids, allenes and imines in comparison to the yields of homoallylic amines achieved with the originally reported catalyst (Pd(OAc)2/P(t-Bu)3), thus extending the scope of the reaction. 31P NMR monitoring studies indicate that distinct intermediates featuring Pd-P bonds originate in the reactions catalyzed by either Pd(OAc)2/P(t-Bu)3 or the pallada(II)cycle/P(t-Bu)3 systems, suggesting that the role of the pallada(II)cycles is more complex than just precatalysts. The importance of an additional phosphine ligand in the reactions catalyzed the pallada(II)cycles was established, and its role in the catalytic cycle has been proposed. Insights into the nature of the reactive intermediates that limit the performance of the originally reported catalytic systems has been gained.
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