1
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Deng Y, Carnevale V, Ditchfield R, Pletneva EV. Applications of the Newly Developed Force-Field Parameters Uncover a Dynamic Nature of Ω-Loop C in the Lys-Ligated Alkaline Form of Cytochrome c. J Phys Chem B 2024; 128:5935-5949. [PMID: 38864552 DOI: 10.1021/acs.jpcb.4c00625] [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: 06/13/2024]
Abstract
Lys-ligated cytochromes make up an emerging family of heme proteins. Density functional theory calculations on the amine/imidazole-ligated c-type ferric heme were employed to develop force-field parameters for molecular dynamics (MD) simulations of structural and dynamic features of these proteins. The new force-field parameters were applied to the alkaline form of yeast iso-1 cytochrome c to rationalize discrepancies resulting from distinct experimental conditions in prior structural studies and to provide insights into the mechanisms of the alkaline transition. Our simulations have revealed the dynamic nature of Ω-loop C in the Lys-ligated protein and its unfolding in the Lys-ligated conformer having this loop in the same position as in the native Met-ligated protein. The proximity of Tyr67 or Tyr74 to the Lys ligand of ferric heme iron suggests a possible mechanism of the backward alkaline transition where a proton donor Tyr assists in Lys dissociation. The developed force-field parameters will be useful in structural and dynamic characterization of other native or engineered Lys-ligated heme proteins.
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Affiliation(s)
- Yunling Deng
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
| | - Vincenzo Carnevale
- Institute for Genomics and Evolutionary Medicine, Institute for Computational Molecular Science, and Department of Biology, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Robert Ditchfield
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
| | - Ekaterina V Pletneva
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
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2
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Zhang J, Gao LX, Chen W, Zhong JJ, Qian C, Zhou WW. Rational Design of Daunorubicin C-14 Hydroxylase Based on the Understanding of Its Substrate-Binding Mechanism. Int J Mol Sci 2023; 24:ijms24098337. [PMID: 37176043 PMCID: PMC10179135 DOI: 10.3390/ijms24098337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/26/2023] [Accepted: 05/03/2023] [Indexed: 05/15/2023] Open
Abstract
Doxorubicin is one of the most widely used antitumor drugs and is currently produced via the chemical conversion method, which suffers from high production costs, complex product separation processes, and serious environmental pollution. Biocatalysis is considered a more efficient and environment-friendly method for drug production. The cytochrome daunorubicin C-14 hydroxylase (DoxA) is the essential enzyme catalyzing the conversion of daunorubicin to doxorubicin. Herein, the DoxA from Streptomyces peucetius subsp. caesius ATCC 27952 was expressed in Escherichia coli, and the rational design strategy was further applied to improve the enzyme activity. Eight amino acid residues were identified as the key sites via molecular docking. Using a constructed screening library, we obtained the mutant DoxA(P88Y) with a more rational protein conformation, and a 56% increase in bioconversion efficiency was achieved by the mutant compared to the wild-type DoxA. Molecular dynamics simulation was applied to understand the relationship between the enzyme's structural property and its substrate-binding efficiency. It was demonstrated that the mutant DoxA(P88Y) formed a new hydrophobic interaction with the substrate daunorubicin, which might have enhanced the binding stability and thus improved the catalytic activity. Our work lays a foundation for further exploration of DoxA and facilitates the industrial process of bio-production of doxorubicin.
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Affiliation(s)
- Jing Zhang
- College of Biosystems Engineering and Food Science, Ningbo Research Institute, Zhejiang University, Hangzhou 310058, China
- School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, NSW 2006, Australia
| | - Ling-Xiao Gao
- College of Biosystems Engineering and Food Science, Ningbo Research Institute, Zhejiang University, Hangzhou 310058, China
| | - Wei Chen
- College of Biosystems Engineering and Food Science, Ningbo Research Institute, Zhejiang University, Hangzhou 310058, China
| | - Jian-Jiang Zhong
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Chao Qian
- College of Chemical and Biological Engineering, Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology, Zhejiang University, Hangzhou 310027, China
| | - Wen-Wen Zhou
- College of Biosystems Engineering and Food Science, Ningbo Research Institute, Zhejiang University, Hangzhou 310058, China
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3
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Yang L, Yang D, Wang Q, Li J, Li HL, Pan L. Functional expression and purification of DoxA, a key cytochrome P450 from Streptomyces peucetius ATCC 27952. PeerJ 2022; 10:e14373. [PMID: 36411834 PMCID: PMC9675340 DOI: 10.7717/peerj.14373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 10/19/2022] [Indexed: 11/17/2022] Open
Abstract
The antitumor drug doxorubicin is widely used in clinical practice. However, the low yield and high cost of this drug highlight the urgent need for cost-effective processes to rapidly manufacture antitumor drugs at scale. In the biosynthesis pathway, the multi-functional cytochrome P450 enzyme DoxA catalyzes the last three steps of hydroxylation. The final conversion of daunorubicin to doxorubicin is the rate-limiting step. In our work, the DoxA has been expressed with the ferredoxin reductase FDR2 and the ferredoxin FDX1 and purified to homogeneous. The reduced carbon monoxide difference spectroscopy, heme concentration, and enzymatic characteristic were characterized. These studies suggest an approach for engineering Streptomyces P450s with functional expression for mechanistic and structural studies.
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Affiliation(s)
- Liyan Yang
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China
| | - Dengfeng Yang
- Guangxi Key Laboratory of Marine Natural Products and Combinatorial Biosynthesis Chemistry, Guangxi Academy of Sciences, Nanning, China
| | - Qingyan Wang
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China
| | - Juan Li
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China
| | - Hong-Liang Li
- Guangxi Key Laboratory of Marine Natural Products and Combinatorial Biosynthesis Chemistry, Guangxi Academy of Sciences, Nanning, China
| | - Lixia Pan
- National Engineering Research Center for Non-Food Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China
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4
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The structure and characterization of human cytochrome P450 8B1 supports future drug design for non-alcoholic fatty liver disease and diabetes. J Biol Chem 2022; 298:102344. [PMID: 35944583 PMCID: PMC9463588 DOI: 10.1016/j.jbc.2022.102344] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 07/25/2022] [Accepted: 07/26/2022] [Indexed: 11/20/2022] Open
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5
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Nienhaus K, Sharma V, Nienhaus GU, Podust LM. Homodimerization Counteracts the Detrimental Effect of Nitrogenous Heme Ligands on the Enzymatic Activity of Acanthamoeba castellanii CYP51. Biochemistry 2022; 61:1363-1377. [PMID: 35730528 DOI: 10.1021/acs.biochem.2c00198] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Acanthamoeba castellanii is a free-living amoeba that can cause severe eye and brain infections in humans. At present, there is no uniformly effective treatment for any of these infections. However, sterol 14α-demethylases (CYP51s), heme-containing cytochrome P450 enzymes, are known to be validated drug targets in pathogenic fungi and protozoa. The catalytically active P450 form of CYP51 from A. castellanii (AcCYP51) is stabilized against conversion to the inactive P420 form by dimerization. In contrast, Naegleria fowleri CYP51 (NfCYP51) is monomeric in its active P450 and inactive P420 forms. For these two CYP51 enzymes, we have investigated the interplay between the enzyme activity and oligomerization state using steady-state and time-resolved UV-visible absorption spectroscopy. In both enzymes, the P450 → P420 transition is favored under reducing conditions. The transition is accelerated at higher pH, which excludes a protonated thiol as the proximal ligand in P420. Displacement of the proximal thiolate ligand is also promoted by adding exogenous nitrogenous ligands (N-ligands) such as imidazole, isavuconazole, and clotrimazole that bind at the opposite, distal heme side. In AcCYP51, the P450 → P420 transition is faster in the monomer than in the dimer, indicating that the dimeric assembly is critical for stabilizing thiolate coordination to the heme and thus for sustaining AcCYP51 activity. The spectroscopic experiments were complemented with size-exclusion chromatography and X-ray crystallography studies. Collectively, our results indicate that effective inactivation of the AcCYP51 function by azole drugs is due to synergistic interference with AcCYP51 dimerization and promoting irreversible displacement of the proximal heme-thiolate ligand.
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Affiliation(s)
- Karin Nienhaus
- Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), D-76049 Karlsruhe, Germany
| | - Vandna Sharma
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Center for Discovery and Innovation in Parasitic Diseases, University of California San Diego, La Jolla, California 92093, United States
| | - Gerd Ulrich Nienhaus
- Institute of Applied Physics, Karlsruhe Institute of Technology (KIT), D-76049 Karlsruhe, Germany.,Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany.,Institute of Biological and Chemical Systems, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany.,Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States
| | - Larissa M Podust
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Center for Discovery and Innovation in Parasitic Diseases, University of California San Diego, La Jolla, California 92093, United States
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6
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Gable J, Tripathi S, Poulos TL. Structural Insights on the Conversion of Cytochrome P450 to P420. ACS OMEGA 2022; 7:18481-18485. [PMID: 35694512 PMCID: PMC9178766 DOI: 10.1021/acsomega.2c00960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 03/24/2022] [Indexed: 06/15/2023]
Abstract
A characteristic feature of cytochromes P450* is that the complex formed between the ferrous heme iron and carbon monoxide generates an intense absorption band at 450 nm. This unique feature of P450s is due to the proximal thiolate Cys ligand coordinated to the heme iron. Various harsh treatments shift this band to 420 nm, thereby giving P420 which is most often associated with an inactive form of the enzyme. Various explanations have been put forward to explain the P450-to-P420 change ranging from protonation of the Cys heme ligand, displacement of the Cys ligand, or replacement of the Cys ligand with His. There are two crystal structures of the well-studied cytochrome P450cam that have a high fraction of P420. In one, P450cam is cross-linked to its redox partner, putidaredoxin (Pdx), and the second is P450cam crystallized in the absence of substrate. In both of these structures, a significant part of the substrate pocket is disordered and the poor quality of the electron density for the substrate indicates substantial disorder. However, in both structures there is no detectable change in the Cys-iron ligation or surrounding structure. These results indicate that the P450-to-P420 switch is due primarily to an opening and disordering around the substrate binding pocket and not ligand displacement or ligand swapping. Since it remains a possibility that ligand swapping could be responsible for P420 in some cases, we mutated to Gln the 3 His residues (352, 355, and 361) close enough to the proximal side of the heme that could possibly serve as heme ligands. The triple variant forms P420 which indicates that swapping Cys for His is not a requirement for the P450-to-P420 switch.
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Affiliation(s)
- Jessica
A. Gable
- Departments
of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, California 92697-3900, United States
| | - Sarvind Tripathi
- Departments
of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, California 92697-3900, United States
| | - Thomas L Poulos
- Departments
of Molecular Biology and Biochemistry, Pharmaceutical Sciences, and Chemistry, University of California, Irvine, California 92697-3900, United States
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7
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Gout J, Meuris F, Desbois A, Dorlet P. In vitro coordination of Fe-protoheme with amyloid β is non-specific and exhibits multiple equilibria. J Inorg Biochem 2021; 227:111664. [PMID: 34955310 DOI: 10.1016/j.jinorgbio.2021.111664] [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: 08/07/2021] [Revised: 10/20/2021] [Accepted: 11/02/2021] [Indexed: 10/19/2022]
Abstract
In addition to copper and zinc, heme is thought to play a role in Alzheimer's disease and its metabolism is strongly affected during the course of this disease. Amyloid β, the peptide associated with Alzheimer's disease, was shown to bind heme in vitro with potential catalytic activity linked to oxidative stress. To date, there is no direct determination of the structure of this complex. In this work, we studied the binding mode of heme to amyloid β in different conditions of pH and redox state by using isotopically labelled peptide in combination with advanced magnetic and vibrational spectroscopic methods. Our results show that the interaction between heme and amyloid β leads to a variety of species in equilibrium. The formation of these species seems to depend on many factors suggesting that the binding site is neither very strong nor highly specific. In addition, our data do not support the currently accepted model where a water molecule is bound to the ferric heme as sixth ligand. They also exclude structural models mimicking a peroxidatic site in the amyloid β-Fe-protoheme complexes.
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Affiliation(s)
- Jérôme Gout
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Laboratoire Stress Oxydant et Détoxication, Gif-sur-Yvette, France
| | - Floriane Meuris
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Laboratoire Stress Oxydant et Détoxication, Gif-sur-Yvette, France
| | - Alain Desbois
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Laboratoire Stress Oxydant et Détoxication, Gif-sur-Yvette, France.
| | - Pierre Dorlet
- CNRS, Aix-Marseille Université, BIP, IMM, Marseille, France; Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Laboratoire Stress Oxydant et Détoxication, Gif-sur-Yvette, France.
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8
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Zhong F, Alden SL, Hughes RP, Pletneva EV. Comparing Properties of Common Bioinorganic Ligands with Switchable Variants of Cytochrome c. Inorg Chem 2021; 61:1207-1227. [PMID: 34699724 DOI: 10.1021/acs.inorgchem.1c02322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ligand substitution at the metal center is common in catalysis and signal transduction of metalloproteins. Understanding the effects of particular ligands, as well as the polypeptide surrounding, is critical for uncovering mechanisms of these biological processes and exploiting them in the design of bioinspired catalysts and molecular devices. A series of switchable K79G/M80X/F82C (X = Met, His, or Lys) variants of cytochrome (cyt) c was employed to directly compare the stability of differently ligated proteins and activation barriers for Met, His, and Lys replacement at the ferric heme iron. Studies of these variants and their nonswitchable counterparts K79G/M80X have revealed stability trends Met < Lys < His and Lys < His < Met for the protein FeIII-X and FeII-X species, respectively. The differences in the hydrogen-bonding interactions in folded proteins and in solvation of unbound X in the unfolded proteins explain these trends. Calculations of free energy of ligand dissociation in small heme model complexes reveal that the ease of the FeIII-X bond breaking increases in the series amine < imidazole < thioether, mirroring trends in hardness of these ligands. Experimental rate constants for X dissociation in differently ligated cyt c variants are consistent with this sequence, but the differences between Met and His dissociation rates are attenuated because the former process is limited by the heme crevice opening. Analyses of activation parameters and comparisons to those for the Lys-to-Met ligand switch in the alkaline transition suggest that ligand dissociation is entropically driven in all the variants and accompanied by Lys protonation at neutral pH. The described thiolate redox-linked switches have offered a wealth of new information about interactions of different protein-derived ligands with the heme iron in cyt c model proteins, and we anticipate that the strategy of employing these switches could benefit studies of other redox metalloproteins and model complexes.
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Affiliation(s)
- Fangfang Zhong
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
| | - Stephanie L Alden
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
| | - Russell P Hughes
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
| | - Ekaterina V Pletneva
- Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States
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9
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Shimizu T, Hayashi Y, Arai M, McGlynn SE, Masuda T, Masuda S. Repressor Activity of SqrR, a Master Regulator of Persulfide-Responsive Genes, Is Regulated by Heme Coordination. PLANT & CELL PHYSIOLOGY 2021; 62:100-110. [PMID: 33169162 DOI: 10.1093/pcp/pcaa144] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Accepted: 11/03/2020] [Indexed: 06/11/2023]
Abstract
Reactive sulfur species (RSS) are involved in bioactive regulation via persulfidation of proteins. However, how cells regulate RSS-based signaling and RSS metabolism is poorly understood, despite the importance of universal regulation systems in biology. We previously showed that the persulfide-responsive transcriptional factor SqrR acts as a master regulator of sulfide-dependent photosynthesis in proteobacteria. Here, we demonstrated that SqrR also binds heme at a near one-to-one ratio with a binding constant similar to other heme-binding proteins. Heme does not change the DNA-binding pattern of SqrR to the target gene promoter region; however, DNA-binding affinity of SqrR is reduced by the binding of heme, altering its regulatory activity. Circular dichroism spectroscopy clearly showed secondary structural changes in SqrR by the heme binding. Incremental change in the intracellular heme concentration is associated with small, but significant reduction in the transcriptional repression by SqrR. Overall, these results indicate that SqrR has an ability to bind heme to modulate its DNA-binding activity, which may be important for the precise regulation of RSS metabolism in vivo.
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Affiliation(s)
- Takayuki Shimizu
- Department of Life Science and Technology, Tokyo Institute of Technology, Kanagawa, Japan
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Yuuki Hayashi
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Munehito Arai
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
- Department of Physics, The University of Tokyo, Tokyo, Japan
| | - Shawn E McGlynn
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Tatsuru Masuda
- Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Shinji Masuda
- Department of Life Science and Technology, Tokyo Institute of Technology, Kanagawa, Japan
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
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10
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Sharma V, Shing B, Hernandez-Alvarez L, Debnath A, Podust LM. Domain-Swap Dimerization of Acanthamoeba castellanii CYP51 and a Unique Mechanism of Inactivation by Isavuconazole. Mol Pharmacol 2020; 98:770-780. [PMID: 33008918 DOI: 10.1124/molpharm.120.000092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 09/17/2020] [Indexed: 01/14/2023] Open
Abstract
Cytochromes P450 (P450, CYP) metabolize a wide variety of endogenous and exogenous lipophilic molecules, including most drugs. Sterol 14α-demethylase (CYP51) is a target for antifungal drugs known as conazoles. Using X-ray crystallography, we have discovered a domain-swap homodimerization mode in CYP51 from a human pathogen, Acanthamoeba castellanii CYP51 (AcCYP51). Recombinant AcCYP51 with a truncated transmembrane helix was purified as a heterogeneous mixture corresponding to the dimer and monomer units. Spectral analyses of these two populations have shown that the CO-bound ferrous form of the dimeric protein absorbed at 448 nm (catalytically competent form), whereas the monomeric form absorbed at 420 nm (catalytically incompetent form). AcCYP51 dimerized head-to-head via N-termini swapping, resulting in formation of a nonplanar protein-protein interface exceeding 2000 Å2 with a total solvation energy gain of -35.4 kcal/mol. In the dimer, the protomers faced each other through the F and G α-helices, thus blocking the substrate access channel. In the presence of the drugs clotrimazole and isavuconazole, the AcCYP51 drug complexes crystallized as monomers. Although clotrimazole-bound AcCYP51 adopted a typical CYP monomer structure, isavuconazole-bound AcCYP51 failed to refold 74 N-terminal residues. The failure of AcCYP51 to fully refold upon inhibitor binding in vivo would cause an irreversible loss of a structurally aberrant enzyme through proteolytic degradation. This assumption explains the superior potency of isavuconazole against A. castellanii The dimerization mode observed in this work is compatible with membrane association and may be relevant to other members of the CYP family of biologic, medical, and pharmacological importance. SIGNIFICANCE STATEMENT: We investigated the mechanism of action of antifungal drugs in the human pathogen Acanthamoeba castellanii. We discovered that the enzyme target [Acanthamoeba castellanii sterol 14α-demethylase (AcCYP51)] formed a dimer via an N-termini swap, whereas drug-bound AcCYP51 was monomeric. In the AcCYP51-isavuconazole complex, the protein target failed to refold 74 N-terminal residues, suggesting a fundamentally different mechanism of AcCYP51 inactivation than only blocking the active site. Proteolytic degradation of a structurally aberrant enzyme would explain the superior potency of isavuconazole against A. castellanii.
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Affiliation(s)
- Vandna Sharma
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Center for Discovery and Innovation in Parasitic Diseases, University of California San Diego, La Jolla, California (V.S., B.S., L.H.-A., A.D., L.M.P.) and Departamento de Física, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil (L.H.-A.)
| | - Brian Shing
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Center for Discovery and Innovation in Parasitic Diseases, University of California San Diego, La Jolla, California (V.S., B.S., L.H.-A., A.D., L.M.P.) and Departamento de Física, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil (L.H.-A.)
| | - Lilian Hernandez-Alvarez
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Center for Discovery and Innovation in Parasitic Diseases, University of California San Diego, La Jolla, California (V.S., B.S., L.H.-A., A.D., L.M.P.) and Departamento de Física, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil (L.H.-A.)
| | - Anjan Debnath
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Center for Discovery and Innovation in Parasitic Diseases, University of California San Diego, La Jolla, California (V.S., B.S., L.H.-A., A.D., L.M.P.) and Departamento de Física, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil (L.H.-A.)
| | - Larissa M Podust
- Skaggs School of Pharmacy and Pharmaceutical Sciences, Center for Discovery and Innovation in Parasitic Diseases, University of California San Diego, La Jolla, California (V.S., B.S., L.H.-A., A.D., L.M.P.) and Departamento de Física, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista Julio de Mesquita Filho, São José do Rio Preto, São Paulo, Brazil (L.H.-A.)
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11
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Steck V, Kolev JN, Ren X, Fasan R. Mechanism-Guided Design and Discovery of Efficient Cytochrome P450-Derived C-H Amination Biocatalysts. J Am Chem Soc 2020; 142:10343-10357. [PMID: 32407077 DOI: 10.1021/jacs.9b12859] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cytochromes P450 have been recently identified as a promising class of biocatalysts for mediating C-H aminations via nitrene transfer, a valuable transformation for forging new C-N bonds. The catalytic efficiency of P450s in these non-native transformations is however significantly inferior to that exhibited by these enzymes in their native monooxygenase function. Using a mechanism-guided strategy, we report here the rational design of a series of P450BM3-based variants with dramatically enhanced C-H amination activity acquired through disruption of the native proton relay network and other highly conserved structural elements within this class of enzymes. This approach further guided the identification of XplA and BezE, two "atypical" natural P450s implicated in the degradation of a man-made explosive and in benzastatins biosynthesis, respectively, as very efficient C-H aminases. Both XplA and BezE could be engineered to further improve their C-H amination reactivity, which demonstrates their evolvability for abiological reactions. These engineered and natural P450 catalysts can promote the intramolecular C-H amination of arylsulfonyl azides with over 10 000-14 000 catalytic turnovers, ranking among the most efficient nitrene transfer biocatalysts reported to date. Mechanistic and structure-reactivity studies provide insights into the origin of the C-H amination reactivity enhancement and highlight the divergent structural requirements inherent to supporting C-H amination versus C-H monooxygenation reactivity within this class of enzymes. Overall, this work provides new promising scaffolds for the development of nitrene transferases and demonstrates the value of mechanism-driven rational design as a strategy for improving the catalytic efficiency of metalloenzymes in the context of abiological transformations.
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Affiliation(s)
- Viktoria Steck
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Joshua N Kolev
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Xinkun Ren
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Rudi Fasan
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
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12
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Barr JT, Wang Z, Min X, Wienkers HJ, Rock BM, Rock DA, Wienkers LC. Mechanistic Studies of Cytochrome P450 3A4 Time-Dependent Inhibition Using Two Cysteine-Targeting Electrophiles. Drug Metab Dispos 2020; 48:508-514. [DOI: 10.1124/dmd.119.089813] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 02/21/2020] [Indexed: 01/15/2023] Open
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13
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Lau ICK, Feyereisen R, Nelson DR, Bell SG. Analysis and preliminary characterisation of the cytochrome P450 monooxygenases from Frankia sp. EuI1c (Frankia inefficax sp.). Arch Biochem Biophys 2019; 669:11-21. [PMID: 31082352 DOI: 10.1016/j.abb.2019.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/09/2019] [Accepted: 05/09/2019] [Indexed: 10/26/2022]
Abstract
Frankia bacteria are nitrogen fixing species from the Actinobacterium phylum which live on the root nodules of plants. They have been hypothesised to have significant potential for natural product biosynthesis. The cytochrome P450 monooxygenase complement of Frankia sp. EuI1c (Frankia inefficax sp.), which comprises 68 members, was analysed. Several members belonged to previously uncharacterised bacterial P450 families. There was an unusually high number of CYP189 family members (21) suggesting that this family has undergone gene duplication events which are classified as "blooms". The likely electron transfer partners for the P450 enzymes were also identified and analysed. These consisted of predominantly [3Fe-4S] cluster containing ferredoxins (eight), a single [2Fe-2S] ferredoxin and a couple of ferredoxin reductases. Three of these CYP family members were produced and purified, using Escherichia coli as a host, and their substrate range was characterised. CYP1027H1 and CYP150A20 bound a broad range of norisoprenoids and terpenoids. CYP1074A2 was highly specific for certain steroids including testosterone, progesterone, stanolone and 4-androstene-3,17-dione. It is likely that steroids are the physiological substrates of CYP1074A2. These results also give an indication that terpenoids are the likely substrates of CYP1027H1 and CYP150A2. The large number of P450s belonging to distinct families as well as the associated electron transfer partners found in different Frankia strains highlights the importance of this family of enzymes has in the secondary metabolism of these bacteria.
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Affiliation(s)
- Ian C K Lau
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia
| | - René Feyereisen
- Department of Plant and Environmental Sciences, University of Copenhagen, Copenhagen, Denmark
| | - David R Nelson
- University of Tennessee Health Science Center, Dept. of Microbiology, Immunology and Biochemistry, 858 Madison Ave. Suite G01, Memphis, TN, 38163, USA
| | - Stephen G Bell
- Department of Chemistry, University of Adelaide, Adelaide, SA, 5005, Australia.
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14
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Abstract
Genes encoding cytochrome P450 (CYP; P450) enzymes occur widely in the Archaea, Bacteria, and Eukarya, where they play important roles in metabolism of endogenous regulatory molecules and exogenous chemicals. We now report that genes for multiple and unique P450s occur commonly in giant viruses in the Mimiviridae, Pandoraviridae, and other families in the proposed order Megavirales. P450 genes were also identified in a herpesvirus (Ranid herpesvirus 3) and a phage (Mycobacterium phage Adler). The Adler phage P450 was classified as CYP102L1, and the crystal structure of the open form was solved at 2.5 Å. Genes encoding known redox partners for P450s (cytochrome P450 reductase, ferredoxin and ferredoxin reductase, and flavodoxin and flavodoxin reductase) were not found in any viral genome so far described, implying that host redox partners may drive viral P450 activities. Giant virus P450 proteins share no more than 25% identity with the P450 gene products we identified in Acanthamoeba castellanii, an amoeba host for many giant viruses. Thus, the origin of the unique P450 genes in giant viruses remains unknown. If giant virus P450 genes were acquired from a host, we suggest it could have been from an as yet unknown and possibly ancient host. These studies expand the horizon in the evolution and diversity of the enormously important P450 superfamily. Determining the origin and function of P450s in giant viruses may help to discern the origin of the giant viruses themselves.
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15
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Mondal A, Das M, Mazumdar S. Substitution of iron with cobalt in the prosthetic group of bacterial cytochrome P450: Effects on the stability and structure of the protein. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.12.043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Horn M, Nienhaus K, Nienhaus GU. Kinetic Study of Ligand Binding and Conformational Changes in Inducible Nitric Oxide Synthase. J Phys Chem B 2018; 122:11048-11057. [PMID: 29965771 DOI: 10.1021/acs.jpcb.8b05137] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Nitric oxide synthases (NOSs) are heme enzymes that generate highly reactive nitric oxide from l-arginine (l-Arg) in a complex mechanism that is still only partially understood. We have studied carbon monoxide (CO) binding to the oxygenase domain of murine inducible NOS (iNOS) by using flash photolysis. The P420 and P450 forms of the enzyme, assigned to a protonated and unprotonated proximal cysteine, through which the heme is anchored to the protein, show markedly different CO rebinding properties. The data suggest that P420 has a widely open distal pocket that admits water. CO rebinding to the P450 form strongly depends on the presence of the substrate l-Arg, the intermediate Nω-hydroxy-l-arginine, and the cofactor tetrahydrobiopterin. After adding these small molecules to the enzyme solution, the CO kinetics change slowly over the hours. This process can be described as a relaxation from a fast rebinding, metastable species to a slowly rebinding, thermodynamically stable species, which we associate with the enzymatically active form. Our results allow us to determine kinetic parameters of l-Arg binding to the ferrous deoxy iNOS protein for the first time and also provide clues regarding the nature of structural differences between the two interconverting species.
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Affiliation(s)
- Michael Horn
- Institute of Applied Physics, Karlsruhe Institute of Technology (KIT) , Wolfgang-Gaede-Str. 1 , D-76131 Karlsruhe , Germany
| | - Karin Nienhaus
- Institute of Applied Physics, Karlsruhe Institute of Technology (KIT) , Wolfgang-Gaede-Str. 1 , D-76131 Karlsruhe , Germany
| | - G Ulrich Nienhaus
- Institute of Applied Physics, Karlsruhe Institute of Technology (KIT) , Wolfgang-Gaede-Str. 1 , D-76131 Karlsruhe , Germany.,Institute of Nanotechnology (INT) and Institute of Toxicology and Genetics (ITG), Karlsruhe Institute of Technology (KIT) , D-76344 Eggenstein-Leopoldshafen , Germany.,Department of Physics , University of Illinois at Urbana-Champaign , 1110 West Green Street , Urbana , Illinois 61801 , United States
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17
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Yadav R, Scott EE. Endogenous insertion of non-native metalloporphyrins into human membrane cytochrome P450 enzymes. J Biol Chem 2018; 293:16623-16634. [PMID: 30217815 DOI: 10.1074/jbc.ra118.005417] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 09/13/2018] [Indexed: 11/06/2022] Open
Abstract
Human cytochrome P450 enzymes are membrane-bound heme-containing monooxygenases. As is the case for many heme-containing enzymes, substitution of the metal in the center of the heme can be useful for mechanistic and structural studies of P450 enzymes. For many heme proteins, the iron protoporphyrin prosthetic group can be extracted and replaced with protoporphyrin containing another metal, but human membrane P450 enzymes are not stable enough for this approach. The method reported herein was developed to endogenously produce human membrane P450 proteins with a nonnative metal in the heme. This approach involved coexpression of the P450 of interest, a heme uptake system, and a chaperone in Escherichia coli growing in iron-depleted minimal medium supplemented with the desired trans-metallated protoporphyrin. Using the steroidogenic P450 enzymes CYP17A1 and CYP21A2 and the drug-metabolizing CYP3A4, we demonstrate that this approach can be used with several human P450 enzymes and several different metals, resulting in fully folded proteins appropriate for mechanistic, functional, and structural studies including solution NMR.
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Affiliation(s)
- Rahul Yadav
- From the Departments of Medicinal Chemistry and
| | - Emily E Scott
- From the Departments of Medicinal Chemistry and .,Pharmacology, University of Michigan, Ann Arbor, Michigan 48109
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18
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Spectroscopic evidence supporting neutral thiol ligation to ferrous heme iron. J Biol Inorg Chem 2018; 23:1085-1092. [DOI: 10.1007/s00775-018-1611-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 08/29/2018] [Indexed: 10/28/2022]
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19
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Li Y, Qin B, Li X, Tang J, Chen Y, Zhou L, You S. Selective Oxidations of Cyperenoic Acid by Slightly Reshaping the Binding Pocket of Cytochrome P450 BM3. ChemCatChem 2018. [DOI: 10.1002/cctc.201701088] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yuxin Li
- School of Life Science and Biopharmaceutics; Shenyang Pharmaceutical University; 103 Wenhua Road, Shenhe District Shenyang 110016 P.R. China
| | - Bin Qin
- Wuya College of Innovation; Shenyang Pharmaceutical University; 103 Wenhua Road, Shenhe District Shenyang 110016 P.R. China
| | - Xiaoqin Li
- School of Life Science and Biopharmaceutics; Shenyang Pharmaceutical University; 103 Wenhua Road, Shenhe District Shenyang 110016 P.R. China
| | - Jun Tang
- School of Life Science and Biopharmaceutics; Shenyang Pharmaceutical University; 103 Wenhua Road, Shenhe District Shenyang 110016 P.R. China
| | - Yu Chen
- School of Life Science and Biopharmaceutics; Shenyang Pharmaceutical University; 103 Wenhua Road, Shenhe District Shenyang 110016 P.R. China
| | - Lina Zhou
- School of Life Science and Biopharmaceutics; Shenyang Pharmaceutical University; 103 Wenhua Road, Shenhe District Shenyang 110016 P.R. China
| | - Song You
- School of Life Science and Biopharmaceutics; Shenyang Pharmaceutical University; 103 Wenhua Road, Shenhe District Shenyang 110016 P.R. China
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20
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Nye DB, Preimesberger MR, Majumdar A, Lecomte JTJ. Histidine-Lysine Axial Ligand Switching in a Hemoglobin: A Role for Heme Propionates. Biochemistry 2018; 57:631-644. [PMID: 29271191 DOI: 10.1021/acs.biochem.7b01155] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The hemoglobin of Synechococcus sp. PCC 7002, GlbN, is a monomeric group I truncated protein (TrHb1) that coordinates the heme iron with two histidine ligands at neutral pH. One of these is the distal histidine (His46), a residue that can be displaced by dioxygen and other small molecules. Here, we show with mutagenesis, electronic absorption spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy that at high pH and exclusively in the ferrous state, Lys42 competes with His46 for the iron coordination site. When b heme is originally present, the population of the lysine-bound species remains too small for detailed characterization; however, the population can be increased significantly by using dimethyl-esterified heme. Electronic absorption and NMR spectroscopies showed that the reversible ligand switching process occurs with an apparent pKa of 9.3 and a Lys-ligated population of ∼60% at the basic pH limit in the modified holoprotein. The switching rate, which is slow on the chemical shift time scale, was estimated to be 20-30 s-1 by NMR exchange spectroscopy. Lys42-His46 competition and attendant conformational rearrangement appeared to be related to weakened bis-histidine ligation and enhanced backbone dynamics in the ferrous protein. The pH- and redox-dependent ligand exchange process observed in GlbN illustrates the structural plasticity allowed by the TrHb1 fold and demonstrates the importance of electrostatic interactions at the heme periphery for achieving axial ligand selection. An analogy is drawn to the alkaline transition of cytochrome c, in which Lys-Met competition is detected at alkaline pH, but, in contrast to GlbN, in the ferric state only.
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Affiliation(s)
- Dillon B Nye
- T. C. Jenkins Department of Biophysics, Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - Matthew R Preimesberger
- T. C. Jenkins Department of Biophysics, Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - Ananya Majumdar
- Biomolecular NMR Center, Johns Hopkins University , Baltimore, Maryland 21218, United States
| | - Juliette T J Lecomte
- T. C. Jenkins Department of Biophysics, Johns Hopkins University , Baltimore, Maryland 21218, United States
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21
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Ogura M, Endo R, Ishikawa H, Takeda Y, Uchida T, Iwai K, Kobayashi K, Ishimori K. Redox-dependent axial ligand replacement and its functional significance in heme-bound iron regulatory proteins. J Inorg Biochem 2018; 182:238-248. [PMID: 29449016 DOI: 10.1016/j.jinorgbio.2018.01.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 12/07/2017] [Accepted: 01/08/2018] [Indexed: 11/29/2022]
Abstract
Iron regulatory proteins (IRPs), regulators of iron metabolism in mammalian cells, control the translation of proteins involved in iron uptake, storage and utilization by binding to specific iron-responsive element (IRE) sequences of mRNAs. Two homologs of IRPs (IRP1 and IRP2) have a typical heme regulatory motif (HRM), a consensus sequence found in "heme-regulated proteins". However, specific heme binding to HRM has been reported only for IRP2, which is essential for oxidative modification and loss of binding to target mRNAs. In this paper, we confirmed that IRP1 also specifically binds two molar equivalents of heme, and found that the absorption and resonance Raman spectra of heme-bound IRP1 were quite similar to those of heme-bound IRP2. This shows that the heme environmental structures in IRP1 are close to those of proteins using heme as a regulatory molecule. Pulse radiolysis experiments, however, clearly revealed an axial ligand exchange from Cys to His immediately after the reduction of the heme iron to form a 5-coordinate His-ligated heme in heme-bound IRP2, whereas the 5-coordinate His-ligated heme was not observed after the reduction of heme-bound IRP1. Considering that the oxidative modification is only observed in heme-bound IRP2, but not IRP1, probably owing to the structural flexibility of IRP2, we propose that the transient 5-coordinate His-ligated heme is a prerequisite for oxidative modification of heme-bound IRP2, which functionally differentiates heme binding of IRP2 from that of IRP1.
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Affiliation(s)
- Mariko Ogura
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Ryosuke Endo
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan; Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8530, Japan
| | - Haruto Ishikawa
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8530, Japan
| | - Yukiko Takeda
- Molecular and Cellular Physiology, Graduate School of Medicine, Kyoto University, Kyoto 606-8561, Japan
| | - Takeshi Uchida
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan; Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Kazuhiro Iwai
- Molecular and Cellular Physiology, Graduate School of Medicine, Kyoto University, Kyoto 606-8561, Japan
| | - Kazuo Kobayashi
- The Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - Koichiro Ishimori
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan; Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan.
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22
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23
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Xu H, Ning L, Yang W, Fang B, Wang C, Wang Y, Xu J, Collin S, Laeuffer F, Fourage L, Li S. In vitro oxidative decarboxylation of free fatty acids to terminal alkenes by two new P450 peroxygenases. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:208. [PMID: 28912830 PMCID: PMC5588734 DOI: 10.1186/s13068-017-0894-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 08/28/2017] [Indexed: 05/21/2023]
Abstract
BACKGROUND P450 fatty acid decarboxylases represented by the unusual CYP152 peroxygenase family member OleTJE have been receiving great attention recently since these P450 enzymes are able to catalyze the simple and direct production of 1-alkenes for potential applications in biofuels and biomaterials. To gain more mechanistic insights, broader substrate spectra, and improved decarboxylative activities, it is demanded to discover and investigate more P450 fatty acid decarboxylases. RESULTS Here, we describe for the first time the expression, purification, and in vitro biochemical characterization of two new CYP152 peroxygenases, CYP-Aa162 and CYP-Sm46Δ29, that are capable of decarboxylating straight-chain saturated fatty acids. Both enzymes were found to catalyze the decarboxylation and hydroxylation of a broad range of free fatty acids (C10-C20) with overlapping substrate specificity, yet distinct chemoselectivity. CYP-Sm46Δ29 works primarily as a fatty (lauric) acid decarboxylase (66.1 ± 3.9% 1-undecene production) while CYP-Aa162 more as a fatty (lauric) acid hydroxylase (72.2 ± 0.9% hydroxy lauric acid production). Notably, the optical spectroscopic analysis of functional CYP-Sm46Δ29 revealed no characteristic P450 band, suggesting a unique heme coordination environment. Active-site mutagenesis analysis showed that substitution with the proposed key decarboxylation-modulating residues, His85 and Ile170, enhanced the decarboxylation activity of CYP-Aa162 and P450BSβ, emphasizing the importance of these residues in directing the decarboxylation pathway. Furthermore, the steady-state kinetic analysis of CYP-Aa162 and CYP-Sm46Δ29 revealed both cooperative and substrate inhibition behaviors which are substrate carbon chain length dependent. CONCLUSIONS Our data identify CYP-Sm46Δ29 as an efficient OleTJE-like fatty acid decarboxylase. Oxidative decarboxylation chemoselectivity of the CYP152 decarboxylases is largely dependent upon the carbon chain length of fatty acid substrates and their precise positioning in the enzyme active site. Finally, the kinetic mode analysis of the enzymes could provide important guidance for future process design.
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Affiliation(s)
- Huifang Xu
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
| | - Linlin Ning
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Wenxia Yang
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
| | - Bo Fang
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
| | - Cong Wang
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
| | - Yun Wang
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- Single-Cell Center, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
| | - Jian Xu
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- Single-Cell Center, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
| | - Severine Collin
- Total Refinery and Chemistry, SDR/Biofuels, Tour Coupole, 2, PI. Jean Millier, 92400 Courbevoie, France
| | - Frederic Laeuffer
- Total Refinery and Chemistry, SDR/Biofuels, Tour Coupole, 2, PI. Jean Millier, 92400 Courbevoie, France
| | - Laurent Fourage
- Total Refinery and Chemistry, SDR/Biofuels, Tour Coupole, 2, PI. Jean Millier, 92400 Courbevoie, France
| | - Shengying Li
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101 Shandong China
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Zhang A, Kwan L, Stillman MJ. The spectroscopic impact of interactions with the four Gouterman orbitals from peripheral decoration of porphyrins with simple electron withdrawing and donating groups. Org Biomol Chem 2017; 15:9081-9094. [DOI: 10.1039/c7ob01960b] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Porphyrin β-substitution with strong electron withdrawing groups splits the LUMO, red-shifts the Q band, and introduces a dipole moment.
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Affiliation(s)
- Angel Zhang
- Stillman Bioinorganic Group
- Department of Chemistry
- The University of Western Ontario
- London
- Canada N6A 5B7
| | - Lydia Kwan
- Stillman Bioinorganic Group
- Department of Chemistry
- The University of Western Ontario
- London
- Canada N6A 5B7
| | - Martin J. Stillman
- Stillman Bioinorganic Group
- Department of Chemistry
- The University of Western Ontario
- London
- Canada N6A 5B7
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25
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Rodriguez KJ, Hanlon AM, Lyon CK, Cole JP, Tuten BT, Tooley CA, Berda EB, Pazicni S. Porphyrin-Cored Polymer Nanoparticles: Macromolecular Models for Heme Iron Coordination. Inorg Chem 2016; 55:9493-9496. [DOI: 10.1021/acs.inorgchem.6b01113] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Kyle J. Rodriguez
- Department of Chemistry and ‡Materials Science
Program, University of New Hampshire, 23 Academic Way, Durham, New Hampshire 03824, United States
| | - Ashley M. Hanlon
- Department of Chemistry and ‡Materials Science
Program, University of New Hampshire, 23 Academic Way, Durham, New Hampshire 03824, United States
| | - Christopher K. Lyon
- Department of Chemistry and ‡Materials Science
Program, University of New Hampshire, 23 Academic Way, Durham, New Hampshire 03824, United States
| | - Justin P. Cole
- Department of Chemistry and ‡Materials Science
Program, University of New Hampshire, 23 Academic Way, Durham, New Hampshire 03824, United States
| | - Bryan T. Tuten
- Department of Chemistry and ‡Materials Science
Program, University of New Hampshire, 23 Academic Way, Durham, New Hampshire 03824, United States
| | - Christian A. Tooley
- Department of Chemistry and ‡Materials Science
Program, University of New Hampshire, 23 Academic Way, Durham, New Hampshire 03824, United States
| | - Erik B. Berda
- Department of Chemistry and ‡Materials Science
Program, University of New Hampshire, 23 Academic Way, Durham, New Hampshire 03824, United States
| | - Samuel Pazicni
- Department of Chemistry and ‡Materials Science
Program, University of New Hampshire, 23 Academic Way, Durham, New Hampshire 03824, United States
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26
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Girvan HM, Bradley JM, Cheesman MR, Kincaid JR, Liu Y, Czarnecki K, Fisher K, Leys D, Rigby SEJ, Munro AW. Analysis of Heme Iron Coordination in DGCR8: The Heme-Binding Component of the Microprocessor Complex. Biochemistry 2016; 55:5073-83. [DOI: 10.1021/acs.biochem.6b00204] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hazel M. Girvan
- Centre
for Synthetic Biology of Fine and Specialty Chemicals (SYNBIOCHEM),
Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Justin M. Bradley
- School
of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Myles R. Cheesman
- School
of Chemistry, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, U.K
| | - James R. Kincaid
- Department
of Chemistry, Marquette University, 535 North 14th Street, Milwaukee, Wisconsin 53233, United States
| | - Yilin Liu
- Department
of Chemistry, Marquette University, 535 North 14th Street, Milwaukee, Wisconsin 53233, United States
| | - Kazimierz Czarnecki
- Department
of Chemistry, Marquette University, 535 North 14th Street, Milwaukee, Wisconsin 53233, United States
| | - Karl Fisher
- Centre
for Synthetic Biology of Fine and Specialty Chemicals (SYNBIOCHEM),
Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - David Leys
- Centre
for Synthetic Biology of Fine and Specialty Chemicals (SYNBIOCHEM),
Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Stephen E. J. Rigby
- Centre
for Synthetic Biology of Fine and Specialty Chemicals (SYNBIOCHEM),
Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
| | - Andrew W. Munro
- Centre
for Synthetic Biology of Fine and Specialty Chemicals (SYNBIOCHEM),
Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, U.K
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27
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Yoshimoto FK, Auchus RJ. Rapid kinetic methods to dissect steroidogenic cytochrome P450 reaction mechanisms. J Steroid Biochem Mol Biol 2016; 161:13-23. [PMID: 26472553 PMCID: PMC4841756 DOI: 10.1016/j.jsbmb.2015.10.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 08/12/2015] [Accepted: 10/07/2015] [Indexed: 01/03/2023]
Abstract
All cytochrome P450 enzyme reactions involve a catalytic cycle with several discreet physical or chemical steps. This cycle ends with the formation of the reactive heme iron-oxygen complex, which oxygenates substrate. While the steps might be very similar for each P450 enzyme, the rates of each step varies tremendously for each enzyme and sometimes even for different reactions catalyzed by the same enzyme. For example, the rate-limiting step for most bacterial P450 enzymes, with turnover numbers over 1000s(-1), is the second electron transfer. In contrast, steroidogenic P450s from eukaryotes catalyze much slower reactions, with turnover numbers of ∼5-250min(-1); therefore, assumptions about kinetic properties for the mammalian P450 enzymes based on the bacterial enzymes are tenuous. In order to dissect the rates for individual steps, special techniques that isolate individual steps and/or single turnovers are required. This article will review the theoretical principles and practical considerations for several of these techniques, with illustrative published examples. The reader should gain an appreciation for the appropriate methods used to interrogate particular steps in the P450 reaction cycle.
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Affiliation(s)
- Francis K Yoshimoto
- Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA
| | - Richard J Auchus
- Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine, Ann Arbor, MI 48019, USA; Department of Pharmacology, University of Michigan, Ann Arbor, MI 48019, USA.
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28
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McIntosh JA, Heel T, Buller AR, Chio L, Arnold FH. Structural Adaptability Facilitates Histidine Heme Ligation in a Cytochrome P450. J Am Chem Soc 2015; 137:13861-5. [PMID: 26299431 PMCID: PMC4635421 DOI: 10.1021/jacs.5b07107] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Indexed: 11/29/2022]
Abstract
Almost all known members of the cytochrome P450 (CYP) superfamily conserve a key cysteine residue that coordinates the heme iron. Although mutation of this residue abolishes monooxygenase activity, recent work has shown that mutation to either serine or histidine unlocks non-natural carbene- and nitrene-transfer activities. Here we present the first crystal structure of a histidine-ligated P450. The T213A/C317H variant of the thermostable CYP119 from Sulfolobus acidocaldarius maintains heme iron coordination through the introduced ligand, an interaction that is accompanied by large changes in the overall protein structure. We also find that the axial cysteine C317 may be substituted with any other amino acid without abrogating folding and heme cofactor incorporation. Several of the axial mutants display unusual spectral features, suggesting that they have active sites with unique steric and electronic properties. These novel, highly stable enzyme active sites will be fruitful starting points for investigations of non-natural P450 catalysis and mechanisms.
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Affiliation(s)
- John A. McIntosh
- Division of Chemistry and
Chemical Engineering 210-41, California
Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Thomas Heel
- Division of Chemistry and
Chemical Engineering 210-41, California
Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Andrew R. Buller
- Division of Chemistry and
Chemical Engineering 210-41, California
Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Linda Chio
- Division of Chemistry and
Chemical Engineering 210-41, California
Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Frances H. Arnold
- Division of Chemistry and
Chemical Engineering 210-41, California
Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
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29
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Tang K, Knipp M, Liu BB, Cox N, Stabel R, He Q, Zhou M, Scheer H, Zhao KH, Gärtner W. Redox-dependent Ligand Switching in a Sensory Heme-binding GAF Domain of the Cyanobacterium Nostoc sp. PCC7120. J Biol Chem 2015; 290:19067-80. [PMID: 26063806 DOI: 10.1074/jbc.m115.654087] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Indexed: 11/06/2022] Open
Abstract
The genome of the cyanobacterium Nostoc sp. PCC7120 carries three genes (all4978, all7016, and alr7522) encoding putative heme-binding GAF (cGMP-specific phosphodiesterases, adenylyl cyclases, and FhlA) proteins that were annotated as transcriptional regulators. They are composed of an N-terminal cofactor domain and a C-terminal helix-turn-helix motif. All4978 showed the highest affinity for protoheme binding. The heme binding capability of All7016 was moderate, and Alr7522 did not bind heme at all. The "as isolated" form of All4978, identified by Soret band (λmax = 427 nm), was assigned by electronic absorption, EPR, and resonance Raman spectroscopy as a hexa-coordinated low spin Fe(III) heme with a distal cysteine ligand (absorption of δ-band around 360 nm). The protoheme cofactor is noncovalently incorporated. Reduction of the heme could be accomplished by chemically using sodium dithionite and electrospectrochemically; this latter method yielded remarkably low midpoint potentials of -445 and -453 mV (following Soret and α-band absorption changes, respectively). The reduced form of the heme (Fe(II) state) binds both NO and CO. Cysteine coordination of the as isolated Fe(III) protein is unambiguous, but interestingly, the reduced heme instead displays spectral features indicative of histidine coordination. Cys-His ligand switches have been reported as putative signaling mechanisms in other heme-binding proteins; however, these novel cyanobacterial proteins are the first where such a ligand-switch mechanism has been observed in a GAF domain. DNA binding of the helix-turn-helix domain was investigated using a DNA sequence motif from its own promoter region. Formation of a protein-DNA complex preferentially formed in ferric state of the protein.
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Affiliation(s)
- Kun Tang
- From the State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China, the Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim, Germany
| | - Markus Knipp
- the Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim, Germany, Resolv, Faculty for Chemistry and Biochemistry, Ruhr University Bochum, D-44780 Bochum, Germany, and
| | - Bing-Bing Liu
- From the State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Nicholas Cox
- the Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim, Germany
| | - Robert Stabel
- the Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim, Germany
| | - Qi He
- From the State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Ming Zhou
- From the State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China
| | - Hugo Scheer
- the Department of Biologie I, Ludwig-Maximilians-Universität, Menzinger Strasse 67, D-80638 München, Germany
| | - Kai-Hong Zhao
- From the State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China,
| | - Wolfgang Gärtner
- the Max Planck Institute for Chemical Energy Conversion, Stiftstrasse 34-36, D-45470 Mülheim, Germany,
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30
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Basom EJ, Spearman JW, Thielges MC. Conformational landscape and the selectivity of cytochrome P450cam. J Phys Chem B 2015; 119:6620-7. [PMID: 25955684 DOI: 10.1021/acs.jpcb.5b03896] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Conformational heterogeneity and dynamics likely contribute to the remarkable activity of enzymes but are challenging to characterize experimentally. These features are of particular interest within the cytochrome P450 class of monooxygenases, which are of great academic, medicinal, and biotechnological interest as they recognize a broad range of substrates, such as various lipids, steroid precursors, and xenobiotics, including therapeutics. Here, we use linear and 2D IR spectroscopy to characterize the prototypical P450, cytochrome P450cam, bound to three different substrates, camphor, norcamphor, or thiocamphor, which are hydroxylated with high, low, and intermediate regioselectivity, respectively. The data suggest that specific interactions with the substrate drive the population of two different conformations, one that is associated with high regioselectivity and another associated with lower regioselectivity. Although Y96 mediates a hydrogen bond thought necessary to orient the substrate for high regioselectivity, the population and dynamics of the conformational states are largely unaltered by the Y96F mutation. This study suggests that knowledge of the conformational landscape is central to understanding P450 activity, which has important practical ramifications for the design of therapeutics with optimized pharmacokinetics, and the manipulation of P450s, and possibly other enzymes, for biotechnological applications.
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Affiliation(s)
- Edward J Basom
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - James W Spearman
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Megan C Thielges
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
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31
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Smith DMA, Rosso KM. Possible dynamically gated conductance along heme wires in bacterial multiheme cytochromes. J Phys Chem B 2014; 118:8505-12. [PMID: 24975678 DOI: 10.1021/jp502803y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The staggered cross decaheme configuration of electron transfer cofactors in the outer-membrane cytochrome MtrF serves as a prototype for conformationally gated multiheme electron transport. Derived from the bacterium Shewanella oneidensis, the staggered cross configuration reveals intersecting c-type octaheme and tetraheme "wires" containing thermodynamic "hills" and "valleys" (Proc. Natl. Acad. Sci. U. S. A. 2014, 11, 611-616), suggesting that the protein structure may include a dynamical mechanism for conductance and pathway switching depending on enzymatic functional need. Here, we applied classical molecular and statistical mechanics calculations of large-amplitude protein dynamics in MtrF, to address its potential to modulate pathway conductance, including assessment of the effect of the total charge state. Explicit solvent molecular dynamics simulations of fully oxidized and fully reduced MtrF showed that the slowest mode of collective decaheme motion is 90% similar between the oxidized and reduced states and consists primarily of interheme separation with minor rotational contributions. The frequency of this motion is 1.7 × 10(7) s(-1), both for fully oxidized and fully reduced MtrF, slower than the downhill electron transfer rates between stacked heme pairs at the octaheme termini and faster than the electron transfer rates between parallel hemes in the tetraheme chain. This implies that MtrF uses slow conformational fluctuations to modulate electron flow along the octaheme pathway, apparently for the purpose of increasing the residence time of electrons on lowest potential hemes 4 and 9. This apparent gating mechanism should increase the success rate of electron transfer from MtrF to low potential environmental acceptors via these two solvent-exposed hemes.
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Affiliation(s)
- Dayle M A Smith
- Pacific Northwest National Laboratory, P. O. Box 999, MSIN J4-33, Richland, Washington 99352, United States
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32
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Distal-proximal crosstalk in the heme binding pocket of the NO sensor DNR. Biometals 2014; 27:763-73. [PMID: 25007853 DOI: 10.1007/s10534-014-9770-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 06/25/2014] [Indexed: 01/10/2023]
Abstract
In the opportunistic pathogen Pseudomonas aeruginosa the denitrification process is triggered by nitric oxide (NO) and plays a crucial role for the survival in chronic infection sites as a microaerobic-anaerobic biofilm. This respiratory pathway is transcriptionally induced by DNR, an heme-based gas sensor which positively responds to NO. Molecular details of the NO sensing mechanism employed by DNR are now emerging: we recently reported an in vitro study which dissected, for the first time, the heme-iron environment and identified one of the heme axial ligand (i.e. His187), found to be crucial to respond to NO. Nevertheless, the identification of the second heme axial ligand has been unsuccessful, given that a peculiar phenomenon of ligand switching around the heme-iron presumably occurs in DNR. The unusual heme binding properties of DNR could be due to the remarkable flexibility in solution of DNR itself, which, in turns, is crucial for the sensing activity; protein flexibility and dynamics indeed represent a common strategy employed by heme-based redox sensors, which present features deeply different from those of "canonical" hemeproteins. The capability of DNR to deeply rearrange around the heme-iron as been here demonstrated by means of spectroscopic characterization of the H167A/H187A DNR double mutant, which shows unusual kinetics of binding of NO and CO. Moreover, we show that the alteration (such as histidines mutations) of the distal side of the heme pocket is perceived by the proximal one, possibly via the DNR protein chain.
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