1
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Joy J, Schaefer AJ, Teynor MS, Ess DH. Dynamical Origin of Rebound versus Dissociation Selectivity during Fe-Oxo-Mediated C-H Functionalization Reactions. J Am Chem Soc 2024; 146:2452-2464. [PMID: 38241715 DOI: 10.1021/jacs.3c09891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2024]
Abstract
The mechanism of catalytic C-H functionalization of alkanes by Fe-oxo complexes is often suggested to involve a hydrogen atom transfer (HAT) step with the formation of a radical-pair intermediate followed by diverging pathways for radical rebound, dissociation, or desaturation. Recently, we showed that in some Fe-oxo reactions, the radical pair is a nonstatistical-type intermediate and dynamic effects control rebound versus dissociation pathway selectivity. However, the effect of the solvent cage on the stability and lifetime of the radical-pair intermediate has never been analyzed. Moreover, because of the extreme complexity of motion that occurs during dynamics trajectories, the underlying physical origin of pathway selectivity has not yet been determined. For the reaction between [(TQA_Cl)FeIVO]+ and cyclohexane, here, we report explicit solvent trajectories and machine learning analysis on transition-state sampled features (e.g., vibrational, velocity, and geometric) that identified the transferring hydrogen atom kinetic energy as the most important factor controlling rebound versus nonrebound dynamics trajectories, which provides an explanation for our previously proposed dynamic matching effect in fast rebound trajectories that bypass the radical-pair intermediate. Manual control of the reaction trajectories confirmed the importance of this feature and provides a mechanism to enhance or diminish selectivity for the rebound pathway. This led to a general catalyst design principle and proof-of-principle catalyst design that showcases how to control rebound versus dissociation reaction pathway selectivity.
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Affiliation(s)
- Jyothish Joy
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84604, United States
| | - Anthony J Schaefer
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84604, United States
| | - Matthew S Teynor
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84604, United States
| | - Daniel H Ess
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84604, United States
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2
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Hosaka M, Nagasawa S, Iwabuchi Y. C-H Alkylation of Cubanes via Catalytic Generation of Cubyl Radicals. Org Lett 2024; 26:658-663. [PMID: 38236029 DOI: 10.1021/acs.orglett.3c04019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
A catalytic method for the C-H alkylation of cubanes is described. Some hydrogen atom transfer catalysts enable the direct abstraction of a hydrogen atom from the C-H bond of cubanes, followed by conjugate addition of the generated cubyl radicals to electron-deficient alkenes. Synthetic applications of the functionalization method developed are also described.
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Affiliation(s)
- Masaki Hosaka
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Aramaki, Aoba-ku, Sendai, 980-8578, Japan
| | - Shota Nagasawa
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Aramaki, Aoba-ku, Sendai, 980-8578, Japan
| | - Yoshiharu Iwabuchi
- Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Aramaki, Aoba-ku, Sendai, 980-8578, Japan
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3
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Famulari A, Correddu D, Di Nardo G, Gilardi G, Mitrikas G, Chiesa M, García-Rubio I. Heme Spin Distribution in the Substrate-Free and Inhibited Novel CYP116B5hd: A Multifrequency Hyperfine Sublevel Correlation (HYSCORE) Study. Molecules 2024; 29:518. [PMID: 38276601 PMCID: PMC10819608 DOI: 10.3390/molecules29020518] [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: 12/05/2023] [Revised: 12/29/2023] [Accepted: 01/16/2024] [Indexed: 01/27/2024] Open
Abstract
The cytochrome P450 family consists of ubiquitous monooxygenases with the potential to perform a wide variety of catalytic applications. Among the members of this family, CYP116B5hd shows a very prominent resistance to peracid damage, a property that makes it a promising tool for fine chemical synthesis using the peroxide shunt. In this meticulous study, we use hyperfine spectroscopy with a multifrequency approach (X- and Q-band) to characterize in detail the electronic structure of the heme iron of CYP116B5hd in the resting state, which provides structural details about its active site. The hyperfine dipole-dipole interaction between the electron and proton nuclear spins allows for the locating of two different protons from the coordinated water and a beta proton from the cysteine axial ligand of heme iron with respect to the magnetic axes centered on the iron. Additionally, since new anti-cancer therapies target the inhibition of P450s, here we use the CYP116B5hd system-imidazole as a model for studying cytochrome P450 inhibition by an azo compound. The effects of the inhibition of protein by imidazole in the active-site geometry and electron spin distribution are presented. The binding of imidazole to CYP116B5hd results in an imidazole-nitrogen axial coordination and a low-spin heme FeIII. HYSCORE experiments were used to detect the hyperfine interactions. The combined interpretation of the gyromagnetic tensor and the hyperfine and quadrupole tensors of magnetic nuclei coupled to the iron electron spin allowed us to obtain a precise picture of the active-site geometry, including the orientation of the semi-occupied orbitals and magnetic axes, which coincide with the porphyrin N-Fe-N axes. The electronic structure of the iron does not seem to be affected by imidazole binding. Two different possible coordination geometries of the axial imidazole were observed. The angles between gx (coinciding with one of the N-Fe-N axes) and the projection of the imidazole plane on the heme were determined to be -60° and -25° for each of the two possibilities via measurement of the hyperfine structure of the axially coordinated 14N.
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Affiliation(s)
- Antonino Famulari
- Departamento de Física de la Materia Condensada, Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza, Spain;
- Department of Chemistry, University of Turin, Via Giuria 9, 10125 Torino, Italy;
| | - Danilo Correddu
- Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Torino, Italy (G.D.N.); (G.G.)
| | - Giovanna Di Nardo
- Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Torino, Italy (G.D.N.); (G.G.)
| | - Gianfranco Gilardi
- Department of Life Sciences and Systems Biology, University of Turin, Via Accademia Albertina 13, 10123 Torino, Italy (G.D.N.); (G.G.)
| | - George Mitrikas
- Institute of Nanoscience and Nanotechnology, NCSR Demokritos, 15341 Athens, Greece;
| | - Mario Chiesa
- Department of Chemistry, University of Turin, Via Giuria 9, 10125 Torino, Italy;
| | - Inés García-Rubio
- Departamento de Física de la Materia Condensada, Universidad de Zaragoza, C/Pedro Cerbuna 12, 50009 Zaragoza, Spain;
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain
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4
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Costa GJ, Egbemhenghe A, Liang R. Computational Characterization of the Reactivity of Compound I in Unspecific Peroxygenases. J Phys Chem B 2023; 127:10987-10999. [PMID: 38096487 DOI: 10.1021/acs.jpcb.3c06311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
Unspecific peroxygenases (UPOs) are emerging as promising biocatalysts for selective oxyfunctionalization of unactivated C-H bonds. However, their potential in large-scale synthesis is currently constrained by suboptimal chemical selectivity. Improving the selectivity of UPOs requires a deep understanding of the molecular basis of their catalysis. Recent molecular simulations have sought to unravel UPO's selectivity and inform their design principles. However, most of these studies focused on substrate-binding poses. Few researchers have investigated how the reactivity of CpdI, the principal oxidizing intermediate in the catalytic cycle, influences selectivity in a realistic protein environment. Moreover, the influence of protein electrostatics on the reaction kinetics of CpdI has also been largely overlooked. To bridge this gap, we used multiscale simulations to interpret the regio- and enantioselective hydroxylation of the n-heptane substrate catalyzed by Agrocybe aegerita UPO (AaeUPO). We comprehensively characterized the energetics and kinetics of the hydrogen atom-transfer (HAT) step, initiated by CpdI, and the subsequent oxygen rebound step forming the product. Notably, our approach involved both free energy and potential energy evaluations in a quantum mechanics/molecular mechanics (QM/MM) setting, mitigating the dependence of results on the choice of initial conditions. These calculations illuminate the thermodynamics and kinetics of the HAT and oxygen rebound steps. Our findings highlight that both the conformational selection and the distinct chemical reactivity of different substrate hydrogen atoms together dictate the regio- and enantio-selectivity. Building on our previous study of CpdI's formation in AaeUPO, our results indicate that the HAT step is the rate-limiting step in the overall catalytic cycle. The subsequent oxygen rebound step is swift and retains the selectivity determined by the HAT step. We also pinpointed several polar and charged amino acid residues whose electrostatic potentials considerably influence the reaction barrier of the HAT step. Notably, the Glu196 residue is pivotal for both the CpdI's formation and participation in the HAT step. Our research offers in-depth insights into the catalytic cycle of AaeUPO, which will be instrumental in the rational design of UPOs with enhanced properties.
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Affiliation(s)
- Gustavo J Costa
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States
| | - Abel Egbemhenghe
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States
| | - Ruibin Liang
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States
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5
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Podgorski MN, Lee JHZ, Harbort JS, Nguyen GTH, Doherty DZ, Donald WA, Harmer JR, Bruning JB, Bell SG. Characterisation of the heme aqua-ligand coordination environment in an engineered peroxygenase cytochrome P450 variant. J Inorg Biochem 2023; 249:112391. [PMID: 37837941 DOI: 10.1016/j.jinorgbio.2023.112391] [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: 08/20/2023] [Revised: 09/30/2023] [Accepted: 10/02/2023] [Indexed: 10/16/2023]
Abstract
The cytochrome P450 enzymes (CYPs) are heme-thiolate monooxygenases that catalyse the insertion of an oxygen atom into the C-H bonds of organic molecules. In most CYPs, the activation of dioxygen by the heme is aided by an acid-alcohol pair of residues located in the I-helix of the enzyme. Mutation of the threonine residue of this acid-alcohol pair of CYP199A4, from the bacterium Rhodospeudomonas palustris HaA2, to a glutamate residue induces peroxygenase activity. In the X-ray crystal structures of this variant an interaction of the glutamate side chain and the distal aqua ligand of the heme was observed and this results in this ligand not being readily displaced in the peroxygenase mutant on the addition of substrate. Here we use a range of bulky hydrophobic and nitrogen donor containing ligands in an attempt to displace the distal aqua ligand of the T252E mutant of CYP199A4. Ligand binding was assessed by UV-visible absorbance spectroscopy, native mass spectrometry, electron paramagnetic resonance and X-ray crystallography. None of the ligands tested, even the nitrogen donor ligands which bind directly to the iron in the wild-type enzyme, resulted in displacement of the aqua ligand. Therefore, modification of the I-helix threonine residue to a glutamate residue results in a significant strengthening of the ferric distal aqua ligand. This ligand was not displaced using any of the ligands during this study and this provides a rationale as to why this mutant can shutdown the monooxygenase pathway of this enzyme and switch to peroxygenase activity.
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Affiliation(s)
- Matthew N Podgorski
- Department of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
| | - Joel H Z Lee
- Department of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
| | - Joshua S Harbort
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St Lucia, QLD 4072, Australia
| | - Giang T H Nguyen
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Daniel Z Doherty
- Department of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
| | - William A Donald
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Jeffrey R Harmer
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St Lucia, QLD 4072, Australia
| | - John B Bruning
- School of Biological Sciences, University of Adelaide, SA 5005, Australia
| | - Stephen G Bell
- Department of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia.
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6
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Zhang Y, Cao C, She Y, Yang YF, Houk KN. Molecular Dynamics of Iron Porphyrin-Catalyzed C-H Hydroxylation of Ethylbenzene. J Am Chem Soc 2023. [PMID: 37329571 DOI: 10.1021/jacs.3c03773] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Quasi-classical molecular dynamics (MD) simulations were carried out to study the mechanism of iron porphyrin-catalyzed hydroxylation of ethylbenzene. The hydrogen atom abstraction from ethylbenzene by iron-oxo species is the rate-determining step, which generates the radical pair of iron-hydroxo species and the benzylic radical. In the subsequent radical rebound step, the iron-hydroxo species and benzylic radical recombine to form the hydroxylated product, which is barrierless on the doublet energy surface. In the gas-phase quasi-classical MD study on the doublet energy surface, 45% of the reactive trajectories lead directly to the hydroxylated product, and this increases to 56% in implicit solvent model simulations. The percentage of reactive trajectories leading to the separated radical pair is 98-100% on high-spin (quartet/sextet) energy surfaces. The low-spin state reactivity dominates in the hydroxylation of ethylbenzene, which is dynamically both concerted and stepwise, since the time gap between C-H bond cleavage and C-O bond formation ranges from 41 to 619 fs. By contrast, the high-spin state catalysis is an energetically stepwise process, which has a negligible contribution to the formation of hydroxylation products.
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Affiliation(s)
- Yaling Zhang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Chaoqin Cao
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Yuanbin She
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - Yun-Fang Yang
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310014, China
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
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7
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Coleman T, Podgorski MN, Doyle ML, Scaffidi-Muta JM, Campbell EC, Bruning JB, De Voss JJ, Bell SG. Cytochrome P450-catalyzed oxidation of halogen-containing substrates. J Inorg Biochem 2023; 244:112234. [PMID: 37116269 DOI: 10.1016/j.jinorgbio.2023.112234] [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: 02/17/2023] [Revised: 04/15/2023] [Accepted: 04/15/2023] [Indexed: 04/30/2023]
Abstract
Cytochrome P450 (CYP) enzymes are heme-thiolate monooxygenases which catalyze the oxidation of aliphatic and aromatic C-H bonds and other reactions. The oxidation of halogens by cytochrome P450 enzymes has also been reported. Here we use CYP199A4, from the bacterium Rhodopseudomonas palustris strain HaA2, with a range of para-substituted benzoic acid ligands, which contain halogens, to assess if this enzyme can oxidize these species or if the presence of these electronegative atoms can alter the outcome of P450-catalyzed reactions. Despite binding to the enzyme, there was no detectable oxidation of any of the 4-halobenzoic acids. CYP199A4 was, however, able to efficiently catalyze the oxidation of both 4-chloromethyl- and 4-bromomethyl-benzoic acid to 4-formylbenzoic acid via hydroxylation of the α‑carbon. The 4-chloromethyl substrate bound in the enzyme active site in a similar manner to 4-ethylbenzoic acid. This places the benzylic α‑carbon hydrogens in an unfavorable position for abstraction indicating a degree of substrate mobility must be possible within the active site. CYP199A4 catalyzed oxidations of 4-(2'-haloethyl)benzoic acids yielding α-hydroxylation and desaturation metabolites. The α-hydroxylation product was the major metabolite. The desaturation pathway is significantly disfavored compared to 4-ethylbenzoic acid. This may be due to the electron-withdrawing halogen atom or a different positioning of the substrate within the active site. The latter was demonstrated by the X-ray crystal structures of CYP199A4 with these substrates. Overall, the presence of a halogen atom positioned close to the heme iron can alter the binding orientation and outcomes of enzyme-catalyzed oxidation.
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Affiliation(s)
- Tom Coleman
- Department of Chemistry, University Adelaide, Adelaide, SA 5005, Australia
| | | | - Maya L Doyle
- Department of Chemistry, University Adelaide, Adelaide, SA 5005, Australia
| | | | - Eleanor C Campbell
- Australian Synchrotron, 800 Blackburn Rd, Clayton, Melbourne, VIC 3168. Australia
| | - John B Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia
| | - James J De Voss
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD 4072, Australia
| | - Stephen G Bell
- Department of Chemistry, University Adelaide, Adelaide, SA 5005, Australia.
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8
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Yuan W, Wang F, Qu X, Wang S, Lei B, Shao J, Wang Q, Lin J, Wang W, Dong X. In situ rapid synthesis of hydrogels based on a redox initiator and persistent free radicals. NANOSCALE ADVANCES 2023; 5:1999-2009. [PMID: 36998656 PMCID: PMC10044294 DOI: 10.1039/d3na00038a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 02/14/2023] [Indexed: 06/19/2023]
Abstract
The development of fast and economical hydrogel manufacturing methods is crucial for expanding the application of hydrogels. However, the commonly used rapid initiation system is not conducive to the performance of hydrogels. Therefore, the research focuses on how to improve the preparation speed of hydrogels and avoid affecting the properties of hydrogels. Herein, a redox initiation system with nanoparticle-stabilized persistent free radicals was introduced to rapidly synthesize high-performance hydrogels at room temperature. A redox initiator composed of vitamin C and ammonium persulfate rapidly provides hydroxyl radicals at room temperature. Simultaneously, three-dimensional nanoparticles can stabilize free radicals and prolong their lifetime, thereby increasing the free radical concentration and accelerating the polymerization rate. And casein enabled the hydrogel to achieve impressive mechanical properties, adhesion, and electrical conductivity. This method greatly facilitates the rapid and economical synthesis of high-performance hydrogels and presents broad application prospects in the field of flexible electronics.
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Affiliation(s)
- Wei Yuan
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), School of Physical and Mathematical Sciences, Nanjing Tech University (NanjingTech) Nanjing 211816 China
| | - Fangfang Wang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), School of Physical and Mathematical Sciences, Nanjing Tech University (NanjingTech) Nanjing 211816 China
| | - Xinyu Qu
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), School of Physical and Mathematical Sciences, Nanjing Tech University (NanjingTech) Nanjing 211816 China
| | - Siying Wang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), School of Physical and Mathematical Sciences, Nanjing Tech University (NanjingTech) Nanjing 211816 China
| | - Bing Lei
- School of Physical Science and Information Technology, Liaocheng University Liaocheng 252059 China
| | - Jinjun Shao
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), School of Physical and Mathematical Sciences, Nanjing Tech University (NanjingTech) Nanjing 211816 China
| | - Qian Wang
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), School of Physical and Mathematical Sciences, Nanjing Tech University (NanjingTech) Nanjing 211816 China
| | - Jianjian Lin
- Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology Qingdao 266042 China
| | - Wenjun Wang
- School of Physical Science and Information Technology, Liaocheng University Liaocheng 252059 China
| | - Xiaochen Dong
- Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM), School of Physical and Mathematical Sciences, Nanjing Tech University (NanjingTech) Nanjing 211816 China
- School of Chemistry & Materials Science, Jiangsu Normal University Xuzhou 221116 China
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9
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Joy J, Ess DH. Direct Dynamics Trajectories Demonstrate Dynamic Matching and Nonstatistical Radical Pair Intermediates during Fe-Oxo-Mediated C-H Functionalization Reactions. J Am Chem Soc 2023; 145:7628-7637. [PMID: 36952628 DOI: 10.1021/jacs.3c01196] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
Abstract
The generally proposed mechanism for the reaction between non-heme Fe-oxo complexes and alkane C-H bonds involves a hydrogen atom transfer (HAT) reaction step with a radical pair intermediate that then has competitive radical rebound, dissociation, or desaturation pathways. Here, we report density functional theory-based quasiclassical direct dynamics trajectories that examine post-HAT reaction dynamics. Trajectories revealed that the radical pair intermediate can be a nonstatistical type intermediate without complete internal vibrational redistribution and post-HAT selectivity is generally determined by dynamic effects. Fast rebound trajectories occur through dynamic matching between the rotational motion of the newly formed Fe-OH bond and collision with the alkane radical, and all of this occurs through a nonsynchronous dynamically concerted process that circumvents the radical pair intermediate structure. For radical pair dissociation, trajectories proceeded to the radical pair intermediate for a very brief time, followed by complete dissociation. These trajectories provide a new viewpoint and model to understand the inherent reaction pathway selectivity for non-heme Fe-oxo-mediated C-H functionalization reactions.
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Affiliation(s)
- Jyothish Joy
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
| | - Daniel H Ess
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah 84602, United States
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10
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Vujcic B, Wyllie J, Tania, Burns J, White KF, Cromwell S, Lupton DW, Dutton JL, Soares da Costa TP, Houston SD. Cage hydrocarbons as linkers in dimeric drug design: Case studies with trimethoprim and tedizolid. Bioorg Med Chem Lett 2023; 80:129086. [PMID: 36423825 DOI: 10.1016/j.bmcl.2022.129086] [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: 07/11/2022] [Revised: 10/17/2022] [Accepted: 11/16/2022] [Indexed: 11/22/2022]
Abstract
The looming threat of a "post-antibiotic era" has been caused by a rapid rise in antibacterial resistance and subsequent depletion of effective antibiotic agents in the clinic. An efficient strategy to address this shortfall lies in the reengineering of pre-existing and commercially available antibiotic drugs. This is exemplified by dimerization, a design concept in which two pharmacophores are covalently linked to form a new chemical entity. The cage hydrocarbons cubane (1), bicyclo[2.2.2]octane (BCO) (2), adamantane (3), and bicyclo[1.1.1]pentane (BCP) (4) present themselves as an attractive family of linkers in this regard. In this report, all four hydrocarbon cages were employed as linkers in a series of dimers based on the commercially available antibiotics trimethoprim and tedizolid. A detailed synthetic roadmap for the protection and deprotection of each pharmacophore is outlined. Several members of the trimethoprim series showed activity on par with that of their trimethoprim progenitor, although this was not the case for the tedizolid series. The design strategy outlined herein highlights the utility of the group as a platform for the rapid and modular construction of future novel antibiotics.
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Affiliation(s)
- Biljana Vujcic
- Department of Biochemistry and Chemistry, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Jessica Wyllie
- Department of Biochemistry and Chemistry, La Trobe University, Melbourne, Victoria 3086, Australia; School of Agriculture, Food and Wine, Waite Research Institute, The University of Adelaide, Adelaide 5063, South Australia, Australia
| | - Tania
- Department of Biochemistry and Chemistry, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Jed Burns
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane 4072, Queensland, Australia
| | - Keith F White
- Department of Biochemistry and Chemistry, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Simon Cromwell
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia
| | - David W Lupton
- School of Chemistry, Monash University, Clayton 3800, Victoria, Australia
| | - Jason L Dutton
- Department of Biochemistry and Chemistry, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Tatiana P Soares da Costa
- Department of Biochemistry and Chemistry, La Trobe University, Melbourne, Victoria 3086, Australia; School of Agriculture, Food and Wine, Waite Research Institute, The University of Adelaide, Adelaide 5063, South Australia, Australia
| | - Sevan D Houston
- Department of Biochemistry and Chemistry, La Trobe University, Melbourne, Victoria 3086, Australia; Almac Sciences Ltd, 20 Seagoe Industrial Estate, Craigavon BT63 5QD, United Kingdom.
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11
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Podgorski MN, Coleman T, Churchman LR, Bruning JB, De Voss JJ, Bell SG. Investigating the Active Oxidants Involved in Cytochrome P450 Catalyzed Sulfoxidation Reactions. Chemistry 2022; 28:e202202428. [PMID: 36169207 PMCID: PMC10100219 DOI: 10.1002/chem.202202428] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Indexed: 12/30/2022]
Abstract
Cytochrome P450 (CYP) heme-thiolate monooxygenases catalyze the hydroxylation of the C-H bonds of organic molecules. This reaction is initiated by a ferryl-oxo heme radical cation (Cpd I). These enzymes can also catalyze sulfoxidation reactions and the ferric-hydroperoxy complex (Cpd 0) and the Fe(III)-H2 O2 complex have been proposed as alternative oxidants for this transformation. To investigate this, the oxidation of 4-alkylthiobenzoic acids and 4-methoxybenzoic acid by the CYP199A4 enzyme from Rhodopseudomonas palustris HaA2 was compared using both monooxygenase and peroxygenase pathways. By examining mutants at the mechanistically important, conserved acid alcohol-pair (D251N, T252A and T252E) the relative amounts of the reactive intermediates that would form in these reactions were disturbed. Substrate binding and X-ray crystal structures helped to understand changes in the activity and enabled an attempt to evaluate whether multiple oxidants can participate in these reactions. In peroxygenase reactions the T252E mutant had higher activity towards sulfoxidation than O-demethylation but in the monooxygenase reactions with the WT enzyme the activity of both reactions was similar. The peroxygenase activity of the T252A mutant was greater for sulfoxidation reactions than the WT enzyme, which is the reverse of the activity changes observed for O-demethylation. The monooxygenase activity and coupling efficiency of sulfoxidation and oxidative demethylation were reduced by similar degrees with the T252A mutant. These observations infer that while Cpd I is required for O-dealkylation, another oxidant may contribute to sulfoxidation. Based on the activity of the CYP199A4 mutants it is proposed that this is the Fe(III)-H2 O2 complex which would be more abundant in the peroxide-driven reactions.
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Affiliation(s)
- Matthew N Podgorski
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Tom Coleman
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Luke R Churchman
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Qld, 4072, Australia
| | - John B Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
| | - James J De Voss
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Qld, 4072, Australia
| | - Stephen G Bell
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia
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12
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Lee JHZ, Podgorski MN, Moir M, Gee AR, Bell SG. Selective Oxidations Using a Cytochrome P450 Enzyme Variant Driven with Surrogate Oxygen Donors and Light. Chemistry 2022; 28:e202201366. [PMID: 35712785 PMCID: PMC9541349 DOI: 10.1002/chem.202201366] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Indexed: 11/08/2022]
Affiliation(s)
- Joel H. Z. Lee
- Department of Chemistry University of Adelaide Adelaide SA 5005 Australia
| | | | - Michael Moir
- National Deuteration Facility Australian Nuclear Science and Technology Organisation (ANSTO) Lucas Heights Sydney NSW 2232 Australia
| | - Alecia R. Gee
- Department of Chemistry University of Adelaide Adelaide SA 5005 Australia
| | - Stephen G. Bell
- Department of Chemistry University of Adelaide Adelaide SA 5005 Australia
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13
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Omura K, Aiba Y, Suzuki K, Ariyasu S, Sugimoto H, Shoji O. A P450 Harboring Manganese Protoporphyrin IX Generates a Manganese Analogue of Compound I by Activating Dioxygen. ACS Catal 2022. [DOI: 10.1021/acscatal.2c01345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Keita Omura
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Yuichiro Aiba
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Kazuto Suzuki
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Shinya Ariyasu
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Hiroshi Sugimoto
- RIKEN SPring-8 Center, Harima Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
- Core Research for Evolutional Science and Technology (Japan), Science and Technology Agency, 5 Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan
| | - Osami Shoji
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
- Core Research for Evolutional Science and Technology (Japan), Science and Technology Agency, 5 Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan
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14
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Podgorski MN, Harbort JS, Lee JHZ, Nguyen GT, Bruning JB, Donald WA, Bernhardt PV, Harmer JR, Bell SG. An Altered Heme Environment in an Engineered Cytochrome P450 Enzyme Enables the Switch from Monooxygenase to Peroxygenase Activity. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05877] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Matthew N. Podgorski
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Joshua S. Harbort
- Center for Advanced Imaging, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Joel H. Z. Lee
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Giang T.H. Nguyen
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - John B. Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - William A. Donald
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Paul V. Bernhardt
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Jeffrey R. Harmer
- Center for Advanced Imaging, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Stephen G. Bell
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
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15
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Coleman T, Kirk AM, Lee JHZ, Doherty DZ, Bruning JB, Krenske EH, De Voss JJ, Bell SG. Different Geometric Requirements for Cytochrome P450-Catalyzed Aliphatic Versus Aromatic Hydroxylation Results in Chemoselective Oxidation. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05483] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Tom Coleman
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Alicia M. Kirk
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Joel H. Z. Lee
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Daniel Z. Doherty
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - John B. Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Elizabeth H. Krenske
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - James J. De Voss
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Stephen G. Bell
- Department of Chemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
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16
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Kuznetsov ML, Pombeiro AJ. Metal-free and iron(II)-assisted oxidation of cyclohexane to adipic acid with ozone: A theoretical mechanistic study. J Catal 2021. [DOI: 10.1016/j.jcat.2021.04.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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17
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Coleman T, Kirk AM, Chao RR, Podgorski MN, Harbort JS, Churchman LR, Bruning JB, Bernhardt PV, Harmer JR, Krenske EH, De Voss JJ, Bell SG. Understanding the Mechanistic Requirements for Efficient and Stereoselective Alkene Epoxidation by a Cytochrome P450 Enzyme. ACS Catal 2021. [DOI: 10.1021/acscatal.0c04872] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Tom Coleman
- Department of Chemistry, University Adelaide, Adelaide, South Australia 5005, Australia
| | - Alicia M. Kirk
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Rebecca R. Chao
- Department of Chemistry, University Adelaide, Adelaide, South Australia 5005, Australia
| | - Matthew N. Podgorski
- Department of Chemistry, University Adelaide, Adelaide, South Australia 5005, Australia
| | - Joshua S. Harbort
- Center for Advanced Imaging, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Luke R. Churchman
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - John B. Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Paul V. Bernhardt
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Jeffrey R. Harmer
- Center for Advanced Imaging, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Elizabeth H. Krenske
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - James J. De Voss
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Stephen G. Bell
- Department of Chemistry, University Adelaide, Adelaide, South Australia 5005, Australia
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18
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Tse EG, Houston SD, Williams CM, Savage GP, Rendina LM, Hallyburton I, Anderson M, Sharma R, Walker GS, Obach RS, Todd MH. Nonclassical Phenyl Bioisosteres as Effective Replacements in a Series of Novel Open-Source Antimalarials. J Med Chem 2020; 63:11585-11601. [PMID: 32678591 DOI: 10.1021/acs.jmedchem.0c00746] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The replacement of one chemical motif with another that is broadly similar is a common method in medicinal chemistry to modulate the physical and biological properties of a molecule (i.e., bioisosterism). In recent years, bioisosteres such as cubane and bicyclo[1.1.1]pentane (BCP) have been used as highly effective phenyl mimics. Herein, we show the successful incorporation of a range of phenyl bioisosteres during the open-source optimization of an antimalarial series. Cubane (19) and closo-carborane (23) analogues exhibited improved in vitro potency against Plasmodium falciparum compared to the parent phenyl compound; however, these changes resulted in a reduction in metabolic stability; unusually, enzyme-mediated oxidation was found to take place on the cubane core. A BCP analogue (22) was found to be equipotent to its parent phenyl compound and showed significantly improved metabolic properties. While these results demonstrate the utility of these atypical bioisosteres when used in a medicinal chemistry program, the search to find a suitable bioisostere may well require the preparation of many candidates, in our case, 32 compounds.
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Affiliation(s)
- Edwin G Tse
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Sevan D Houston
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Craig M Williams
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - G Paul Savage
- Ian Wark Laboratory, CSIRO Manufacturing, Melbourne, Victoria 3168, Australia
| | - Louis M Rendina
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Irene Hallyburton
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee DD1 5EH, U.K
| | - Mark Anderson
- Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, School of Life Sciences, University of Dundee, Dundee DD1 5EH, U.K
| | - Raman Sharma
- Pfizer Inc., Groton, Connecticut 06340, United States
| | | | - R Scott Obach
- Pfizer Inc., Groton, Connecticut 06340, United States
| | - Matthew H Todd
- School of Pharmacy, University College London, London WC1N 1AX, U.K
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19
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Watanabe A, Koyamada K, Miyamoto K, Kanazawa J, Uchiyama M. Decarboxylative Bromination of Sterically Hindered Carboxylic Acids with Hypervalent Iodine(III) Reagents. Org Process Res Dev 2020. [DOI: 10.1021/acs.oprd.0c00130] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Ayumi Watanabe
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kenta Koyamada
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kazunori Miyamoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Junichiro Kanazawa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Masanobu Uchiyama
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
- Research Initiative for Supra-Materials (RISM), Shinshu University, Ueda 386-8567, Japan
- Cluster of Pioneering Research (CPR), RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
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20
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Coleman T, Stok JE, Podgorski MN, Bruning JB, De Voss JJ, Bell SG. Structural insights into the role of the acid-alcohol pair of residues required for dioxygen activation in cytochrome P450 enzymes. J Biol Inorg Chem 2020; 25:583-596. [PMID: 32248305 DOI: 10.1007/s00775-020-01781-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 03/22/2020] [Indexed: 10/24/2022]
Abstract
The cytochrome P450 heme monooxygenases commonly use an acid-alcohol pair of residues, within the I-helix, to activate iron-bound dioxygen. This work aims to clarify conflicting reports on the importance of the alcohol functionality in this process. Mutants of the P450, CYP199A4 (CYP199A4D251N and CYP199A4T252A), were prepared, characterised and their crystal structures were solved. The acid residue of CYP199A4 is not part of a salt bridge network, a key feature of paradigmatic model system P450cam. Instead, there is a direct proton delivery network, via a chain of water molecules, extending to the surface. Nevertheless, CYP199A4D251N dramatically reduced the activity of the enzyme consistent with a role in proton delivery. CYP199A4T252A decreased the coupling efficiency of the enzyme with a concomitant increase in the hydrogen peroxide uncoupling pathway. However, the effect of this mutation was much less pronounced than reported with P450cam. Its crystal structures revealed fewer changes at the I-helix, compared to the P450cam system. The structural changes observed within the I-helix of P450cam during oxygen activation do not seem to be required in this P450. These differences are due to the presence of a second threonine residue at position 253, which is absent in P450cam. This threonine forms part of the hydrogen bonding network, resulting in subtle structural changes and is also present across the majority of the P450 superfamily. Overall, the results suggest that while the acid-alcohol pair is important for dioxygen activation this process and the method of proton delivery can differ across P450s.Graphic abstract.
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Affiliation(s)
- Tom Coleman
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Jeanette E Stok
- School of Chemistry and Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Matthew N Podgorski
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia
| | - John B Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, SA, 5005, Australia
| | - James J De Voss
- School of Chemistry and Molecular Bioscience, University of Queensland, Brisbane, QLD, 4072, Australia
| | - Stephen G Bell
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia.
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21
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Podgorski MN, Harbort JS, Coleman T, Stok JE, Yorke JA, Wong LL, Bruning JB, Bernhardt PV, De Voss JJ, Harmer JR, Bell SG. Biophysical Techniques for Distinguishing Ligand Binding Modes in Cytochrome P450 Monooxygenases. Biochemistry 2020; 59:1038-1050. [PMID: 32058707 DOI: 10.1021/acs.biochem.0c00027] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The cytochrome P450 superfamily of heme monooxygenases catalyzes important chemical reactions across nature. The changes in the optical spectra of these enzymes, induced by the addition of substrates or inhibitors, are critical for assessing how these molecules bind to the P450, enhancing or inhibiting the catalytic cycle. Here we use the bacterial CYP199A4 enzyme (Uniprot entry Q2IUO2), from Rhodopseudomonas palustris HaA2, and a range of substituted benzoic acids to investigate different binding modes. 4-Methoxybenzoic acid elicits an archetypal type I spectral response due to a ≥95% switch from the low- to high-spin state with concomitant dissociation of the sixth aqua ligand. 4-(Pyridin-3-yl)- and 4-(pyridin-2-yl)benzoic acid induced different type II ultraviolet-visible (UV-vis) spectral responses in CYP199A4. The former induced a greater red shift in the Soret wavelength (424 nm vs 422 nm) along with a larger overall absorbance change and other differences in the α-, β-, and δ-bands. There were also variations in the ferrous UV-vis spectra of these two substrate-bound forms with a spectrum indicative of Fe-N bond formation with 4-(pyridin-3-yl)benzoic acid. The crystal structures of CYP199A4, with the pyridinyl compounds bound, revealed that while the nitrogen of 4-(pyridin-3-yl)benzoic acid is coordinated to the heme, with 4-(pyridin-2-yl)benzoic acid an aqua ligand remains. Continuous wave and pulse electron paramagnetic resonance data in frozen solution revealed that the substrates are bound in the active site in a form consistent with the crystal structures. The redox potential of each CYP199A4-substrate combination was measured, allowing correlation among binding modes, spectroscopic properties, and the observed biochemical activity.
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Affiliation(s)
- Matthew N Podgorski
- Department of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
| | - Joshua S Harbort
- Center for Advanced Imaging, University of Queensland, Brisbane, QLD 4072, Australia
| | - Tom Coleman
- Department of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
| | - Jeanette E Stok
- School of Chemistry and Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia
| | - Jake A Yorke
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, U.K
| | - Luet-Lok Wong
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, U.K
| | - John B Bruning
- School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia
| | - Paul V Bernhardt
- School of Chemistry and Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia
| | - James J De Voss
- School of Chemistry and Molecular Bioscience, University of Queensland, Brisbane, QLD 4072, Australia
| | - Jeffrey R Harmer
- Center for Advanced Imaging, University of Queensland, Brisbane, QLD 4072, Australia
| | - Stephen G Bell
- Department of Chemistry, University of Adelaide, Adelaide, SA 5005, Australia
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22
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Sarkar MR, Bell SG. Complementary and selective oxidation of hydrocarbon derivatives by two cytochrome P450 enzymes of the same family. Catal Sci Technol 2020. [DOI: 10.1039/d0cy01040e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The cytochrome P450 enzymes CYP101B1 and CYP101C1, from a Novosphingobium bacterium, can efficiently hydroxylate hydrocarbon derivatives containing a carbonyl moiety. Cyclic ketones (C9 to C15) were oxidised with contrasting yet high selectivity.
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Affiliation(s)
| | - Stephen G. Bell
- Department of Chemistry
- University of Adelaide
- Adelaide
- Australia
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