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Phu PN, Barman SK, Ziller JW, Hendrich MP, Borovik AS. Synthesis, characterization and reactivity of a Mn(III)-hydroxido complex as a biomimetic model for lipoxygenase. J Inorg Biochem 2024; 259:112618. [PMID: 38986289 DOI: 10.1016/j.jinorgbio.2024.112618] [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: 03/21/2024] [Revised: 05/19/2024] [Accepted: 05/24/2024] [Indexed: 07/12/2024]
Abstract
Manganese hydroxido (Mn-OH) complexes supported by a tripodal N,N',N″-[nitrilotris(ethane-2,1-diyl)]tris(P,P-diphenylphosphinic amido) ([poat]3-) ligand have been synthesized and characterized by spectroscopic techniques including UV-vis and electron paramagnetic resonance (EPR) spectroscopies. X-ray diffraction (XRD) methods were used to confirm the solid-state molecular structures of {Na2[MnIIpoat(OH)]}2 and {Na[MnIIIpoat(OH)]}2 as clusters that are linked by the electrostatic interactions between the sodium counterions and the oxygen atom of the ligated hydroxido unit and the phosphinic (P=O) amide groups of [poat]3-. Both clusters feature two independent monoanionic fragments in which each contains a trigonal bipyramidal Mn center that is comprised of three equatorial deprotonated amide nitrogen atoms, an apical tertiary amine, and an axial hydroxido ligand. XRD analyses of {Na[MnIIIpoat(OH)]}2 also showed an intramolecular hydrogen bonding interaction between the MnIII-OH unit and P=O group of [poat]3-. Crystalline {Na[MnIIIpoat(OH)]}2 remains as clusters with Na+---O interactions in solution and is unreactive toward external substrates. However, conductivity studies indicated that [MnIIIpoat(OH)]- generated in situ is monomeric and reactivity studies found that it is capable of cleaving C-H bonds, illustrating the importance of solution-phase speciation and its direct effect on chemical reactivity. Synopsis: Manganese-hydroxido complexes were synthesized to study the influence of H-bonds in the secondary coordination sphere and their effects on the oxidative cleavage of substrates containing C-H bonds.
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Affiliation(s)
- Phan N Phu
- Department of Chemistry, University of California, Irvine, CA 92697, United States
| | - Suman K Barman
- Department of Chemistry, University of California, Irvine, CA 92697, United States; Department of Chemical Sciences, India Institute of Science Education and Research (IISER) Mohali, Manauli 140306, India
| | - Joseph W Ziller
- Department of Chemistry, University of California, Irvine, CA 92697, United States
| | - Michael P Hendrich
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, United States
| | - A S Borovik
- Department of Chemistry, University of California, Irvine, CA 92697, United States.
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2
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Whittington C, Sharma A, Hill SG, Iavarone AT, Hoffman BM, Offenbacher AR. Impact of N-Glycosylation on Protein Structure and Dynamics Linked to Enzymatic C-H Activation in the M. oryzae Lipoxygenase. Biochemistry 2024; 63:1335-1346. [PMID: 38690768 DOI: 10.1021/acs.biochem.4c00109] [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: 05/03/2024]
Abstract
Lipoxygenases (LOXs) from pathogenic fungi are potential therapeutic targets for defense against plant and select human diseases. In contrast to the canonical LOXs in plants and animals, fungal LOXs are unique in having appended N-linked glycans. Such important post-translational modifications (PTMs) endow proteins with altered structure, stability, and/or function. In this study, we present the structural and functional outcomes of removing or altering these surface carbohydrates on the LOX from the devastating rice blast fungus, M. oryzae, MoLOX. Alteration of the PTMs did notinfluence the active site enzyme-substrate ground state structures as visualized by electron-nuclear double resonance (ENDOR) spectroscopy. However, removal of the eight N-linked glycans by asparagine-to-glutamine mutagenesis nonetheless led to a change in substrate selectivity and an elevated activation energy for the reaction with substrate linoleic acid, as determined by kinetic measurements. Comparative hydrogen-deuterium exchange mass spectrometry (HDX-MS) analysis of wild-type and Asn-to-Gln MoLOX variants revealed a regionally defined impact on the dynamics of the arched helix that covers the active site. Guided by these HDX results, a single glycan sequon knockout was generated at position 72, and its comparative substrate selectivity from kinetics nearly matched that of the Asn-to-Gln variant. The cumulative data from model glyco-enzyme MoLOX showcase how the presence, alteration, or removal of even a single N-linked glycan can influence the structural integrity and dynamics of the protein that are linked to an enzyme's catalytic proficiency, while indicating that extensive glycosylation protects the enzyme during pathogenesis by protecting it from protease degradation.
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Affiliation(s)
- Chris Whittington
- Department of Chemistry, East Carolina University, Greenville, North Carolina 27858, United States
| | - Ajay Sharma
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - S Gage Hill
- Department of Chemistry, East Carolina University, Greenville, North Carolina 27858, United States
| | - Anthony T Iavarone
- California Institute for Quantitative Biosciences, Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
| | - Brian M Hoffman
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Adam R Offenbacher
- Department of Chemistry, East Carolina University, Greenville, North Carolina 27858, United States
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3
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Amoah AS, Pestov NB, Korneenko TV, Prokhorenko IA, Kurakin GF, Barlev NA. Lipoxygenases at the Intersection of Infection and Carcinogenesis. Int J Mol Sci 2024; 25:3961. [PMID: 38612771 PMCID: PMC11011848 DOI: 10.3390/ijms25073961] [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: 01/31/2024] [Revised: 03/08/2024] [Accepted: 03/28/2024] [Indexed: 04/14/2024] Open
Abstract
The persisting presence of opportunistic pathogens like Pseudomonas aeruginosa poses a significant threat to many immunocompromised cancer patients with pulmonary infections. This review highlights the complexity of interactions in the host's defensive eicosanoid signaling network and its hijacking by pathogenic bacteria to their own advantage. Human lipoxygenases (ALOXs) and their mouse counterparts are integral elements of the innate immune system, mostly operating in the pro-inflammatory mode. Taking into account the indispensable role of inflammation in carcinogenesis, lipoxygenases have counteracting roles in this process. In addition to describing the structure-function of lipoxygenases in this review, we discuss their roles in such critical processes as cancer cell signaling, metastases, death of cancer and immune cells through ferroptosis, as well as the roles of ALOXs in carcinogenesis promoted by pathogenic infections. Finally, we discuss perspectives of novel oncotherapeutic approaches to harness lipoxygenase signaling in tumors.
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Affiliation(s)
- Abdul-Saleem Amoah
- Institute of Biomedical Chemistry, Moscow 119121, Russia; (A.-S.A.); (N.A.B.)
- Laboratory of Molecular Oncology, Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny 141701, Russia
| | - Nikolay B. Pestov
- Institute of Biomedical Chemistry, Moscow 119121, Russia; (A.-S.A.); (N.A.B.)
- Group of Cross-Linking Enzymes, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow 117997, Russia; (T.V.K.); (I.A.P.)
- Laboratory of Tick-Borne Encephalitis and Other Viral Encephalitides, Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products, Moscow 108819, Russia
- Vavilov Institute of General Genetics, Moscow 119991, Russia
| | - Tatyana V. Korneenko
- Group of Cross-Linking Enzymes, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow 117997, Russia; (T.V.K.); (I.A.P.)
| | - Igor A. Prokhorenko
- Group of Cross-Linking Enzymes, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow 117997, Russia; (T.V.K.); (I.A.P.)
| | - Georgy F. Kurakin
- Department of Biochemistry, Pirogov Russian National Research Medical University, Moscow 117513, Russia;
| | - Nickolai A. Barlev
- Institute of Biomedical Chemistry, Moscow 119121, Russia; (A.-S.A.); (N.A.B.)
- Laboratory of Tick-Borne Encephalitis and Other Viral Encephalitides, Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products, Moscow 108819, Russia
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4
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Oliw EH. Thirty years with three-dimensional structures of lipoxygenases. Arch Biochem Biophys 2024; 752:109874. [PMID: 38145834 DOI: 10.1016/j.abb.2023.109874] [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: 09/29/2023] [Revised: 12/17/2023] [Accepted: 12/17/2023] [Indexed: 12/27/2023]
Abstract
The X-ray crystal structures of soybean lipoxygenase (LOX) and rabbit 15-LOX were reported in the 1990s. Subsequent 3D structures demonstrated a conserved U-like shape of the substrate cavities as reviewed here. The 8-LOX:arachidonic acid (AA) complex showed AA bound to the substrate cavity carboxylate-out with C10 at 3.4 Å from the iron metal center. A recent cryo-electron microscopy (EM) analysis of the 12-LOX:AA complex illustrated AA in the same position as in the 8-LOX:AA complex. The 15- and 12-LOX complexes with isoenzyme-specific inhibitors/substrate mimics confirmed the U-fold. 5-LOX oxidizes AA to leukotriene A4, the first step in biosynthesis of mediators of asthma. The X-ray structure showed that the entrance to the substrate cavity was closed to AA by Phe and Tyr residues of a partly unfolded α2-helix. Recent X-ray analysis revealed that soaking with inhibitors shifted the short α2-helix to a long and continuous, which opened the substrate cavity. The α2-helix also adopted two conformations in 15-LOX. 12-LOX dimers consisted of one closed and one open subunit with an elongated α2-helix. 13C-ENDOR-MD computations of the 9-MnLOX:linoleate complex showed carboxylate-out position with C11 placed 3.4 ± 0.1 Å from the catalytic water. 3D structures have provided a solid ground for future research.
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Affiliation(s)
- Ernst H Oliw
- Department of Pharmaceutical Biosciences, Uppsala University, Box 591, SE 751 24, Uppsala, Sweden.
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5
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Khan FS, Goher F, Paulsmeyer MN, Hu CG, Zhang JZ. Calcium (Ca 2+ ) sensors and MYC2 are crucial players during jasmonates-mediated abiotic stress tolerance in plants. PLANT BIOLOGY (STUTTGART, GERMANY) 2023; 25:1025-1034. [PMID: 37422725 DOI: 10.1111/plb.13560] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 06/27/2023] [Indexed: 07/10/2023]
Abstract
Plants evolve stress-specific responses that sense changes in their external environmental conditions and develop various mechanisms for acclimatization and survival. Calcium (Ca2+ ) is an essential stress-sensing secondary messenger in plants. Ca2+ sensors, including calcium-dependent protein kinases (CDPKs), calmodulins (CaMs), CaM-like proteins (CMLs), and calcineurin B-like proteins (CBLs), are involved in jasmonates (JAs) signalling and biosynthesis. Moreover, JAs are phospholipid-derived phytohormones that control plant response to abiotic stresses. The JAs signalling pathway affects hormone-receptor gene transcription by binding to the basic helix-loop-helix (bHLH) transcription factor. MYC2 acts as a master regulator of JAs signalling module assimilated through various genes. The Ca2+ sensor CML regulates MYC2 and is involved in a distinct mechanism mediating JAs signalling during abiotic stresses. This review highlights the pivotal role of the Ca2+ sensors in JAs biosynthesis and MYC2-mediated JAs signalling during abiotic stresses in plants.
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Affiliation(s)
- F S Khan
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China
| | - F Goher
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - M N Paulsmeyer
- United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Vegetable Crops Research Unit, Madison, Wisconsin, USA
| | - C-G Hu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China
| | - J-Z Zhang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China
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6
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Guevara L, Gouge M, Ohler A, Hill SG, Patel S, Offenbacher AR. Effect of solvent viscosity on the activation barrier of hydrogen tunneling in the lipoxygenase reaction. Arch Biochem Biophys 2023; 747:109740. [PMID: 37678425 DOI: 10.1016/j.abb.2023.109740] [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: 07/15/2023] [Revised: 08/22/2023] [Accepted: 09/05/2023] [Indexed: 09/09/2023]
Abstract
Hydrogen tunneling in enzyme reactions has played an important role in linking protein thermal motions to the chemical steps of catalysis. Lipoxygenases (LOXs) have served as model systems for such reactions, showcasing deep hydrogen tunneling mechanisms associated with enzymatic C-H bond cleavage from polyunsaturated fatty acids. Here, we examined the effect of solvent viscosity on the protein thermal motions associated with LOX catalysis using trehalose and glucose as viscogens. Kinetic analysis of the reaction of the paradigm plant orthologue, soybean lipoxygenase (SLO), with linoleic acid revealed no effect on the first-order rate constants, kcat, or activation energy, Ea. Further studies of SLO active site mutants displaying varying Eas, which have been used to probe catalytically relevant motions, likewise provided no evidence for viscogen-dependent motions. Kinetic analyses were extended to a representative fungal LOX from M. oryzae, MoLOX, and a human LOX, 15-LOX-2. While MoLOX behaved similarly to SLO, we show that viscogens inhibit 15-LOX-2 activity. The latter implicates viscogen sensitive, conformational motions in animal LOX reactions. The data provide insight into the role of water hydration layers in facilitating hydrogen (quantum) tunneling in LOX.
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Affiliation(s)
- Luis Guevara
- Department of Chemistry, East Carolina University, Greenville, NC, 27858, USA
| | - Melissa Gouge
- Department of Chemistry and Biochemistry, Ohio Northern University, Ada, OH, 45810, USA
| | - Amanda Ohler
- Department of Chemistry, East Carolina University, Greenville, NC, 27858, USA
| | - S Gage Hill
- Department of Chemistry, East Carolina University, Greenville, NC, 27858, USA
| | - Soham Patel
- Department of Chemistry, East Carolina University, Greenville, NC, 27858, USA
| | - Adam R Offenbacher
- Department of Chemistry, East Carolina University, Greenville, NC, 27858, USA.
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7
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Sharma A, Whittington C, Jabed M, Hill SG, Kostenko A, Yu T, Li P, Doan PE, Hoffman BM, Offenbacher AR. 13C Electron Nuclear Double Resonance Spectroscopy-Guided Molecular Dynamics Computations Reveal the Structure of the Enzyme-Substrate Complex of an Active, N-Linked Glycosylated Lipoxygenase. Biochemistry 2023; 62:1531-1543. [PMID: 37115010 PMCID: PMC10704959 DOI: 10.1021/acs.biochem.3c00119] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Lipoxygenase (LOX) enzymes produce important cell-signaling mediators, yet attempts to capture and characterize LOX-substrate complexes by X-ray co-crystallography are commonly unsuccessful, requiring development of alternative structural methods. We previously reported the structure of the complex of soybean lipoxygenase, SLO, with substrate linoleic acid (LA), as visualized through the integration of 13C/1H electron nuclear double resonance (ENDOR) spectroscopy and molecular dynamics (MD) computations. However, this required substitution of the catalytic mononuclear, nonheme iron by the structurally faithful, yet inactive Mn2+ ion as a spin probe. Unlike canonical Fe-LOXs from plants and animals, LOXs from pathogenic fungi contain active mononuclear Mn2+ metallocenters. Here, we report the ground-state active-site structure of the native, fully glycosylated fungal LOX from rice blast pathogen Magnaporthe oryzae, MoLOX complexed with LA, as obtained through the 13C/1H ENDOR-guided MD approach. The catalytically important distance between the hydrogen donor, carbon-11 (C11), and the acceptor, Mn-bound oxygen, (donor-acceptor distance, DAD) for the MoLOX-LA complex derived in this fashion is 3.4 ± 0.1 Å. The difference of the MoLOX-LA DAD from that of the SLO-LA complex, 3.1 ± 0.1 Å, is functionally important, although is only 0.3 Å, despite the MoLOX complex having a Mn-C11 distance of 5.4 Å and a "carboxylate-out" substrate-binding orientation, whereas the SLO complex has a 4.9 Å Mn-C11 distance and a "carboxylate-in" substrate orientation. The results provide structural insights into reactivity differences across the LOX family, give a foundation for guiding development of MoLOX inhibitors, and highlight the robustness of the ENDOR-guided MD approach to describe LOX-substrate structures.
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Affiliation(s)
- Ajay Sharma
- Department of Chemistry, Northwestern University, Evanston, IL 60208, United States
| | - Chris Whittington
- Department of Chemistry, East Carolina University, Greenville, NC 27858, United States
| | - Mohammed Jabed
- Department of Chemistry, University of North Dakota, Grand Forks, ND 58202, United States
| | - S. Gage Hill
- Department of Chemistry, East Carolina University, Greenville, NC 27858, United States
| | - Anastasiia Kostenko
- Department of Chemistry, East Carolina University, Greenville, NC 27858, United States
| | - Tao Yu
- Department of Chemistry, University of North Dakota, Grand Forks, ND 58202, United States
| | - Pengfei Li
- Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, IL 60660, United States
| | - Peter E. Doan
- Department of Chemistry, Northwestern University, Evanston, IL 60208, United States
| | - Brian M. Hoffman
- Department of Chemistry, Northwestern University, Evanston, IL 60208, United States
| | - Adam R. Offenbacher
- Department of Chemistry, East Carolina University, Greenville, NC 27858, United States
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8
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Savignac JM, Atanasova V, Chereau S, Ducos C, Gallegos N, Ortega V, Ponts N, Richard-Forget F. Carotenoids Occurring in Maize Affect the Redox Homeostasis of Fusarium graminearum and Its Production of Type B Trichothecene Mycotoxins: New Insights Supporting Their Role in Maize Resistance to Giberella Ear Rot. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:3285-3296. [PMID: 36780464 DOI: 10.1021/acs.jafc.2c06877] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Fusarium graminearum is the causal agent of Gibberella ear rot (GER) in maize, a devastating fungal disease resulting in yield reduction and contamination of grains with type B trichothecene (TCTB) mycotoxins. Reducing GER damage requires the implementation of an integrated management strategy in which the use of resistant maize genotypes is a key factor. The present study aimed at providing new phenotyping tools to improve breeding pipelines by investigating the yet understudied contribution of carotenoids to GER resistance. Here, we demonstrated for the first time the efficiency of carotenoid extracts from various maize genotypes to inhibit the production of TCTB by F. graminearum. We further suggested that zeaxanthin could be a key actor of this inhibition efficiency, notably via a negative transcriptional control of several biosynthetic genes of the TCTB pathway. Besides, we demonstrated that zeaxanthin treatments led to profound perturbations in the fungal redox homeostasis by affecting the expression of key genes encoding ROS detoxifying enzymes, several of them being involved in F. graminearum virulence during plant infection. Altogether, our data support the contribution of carotenoids to the mechanisms employed by maize to counteract F. graminearum infection and its production of TCTB.
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Affiliation(s)
- Jean-Marie Savignac
- Syngenta France SAS, Route de Vignolles lieu dit La Grangette, 32220 Lombez, France
- INRAE, UR 1264 Mycology and Food Safety (MycSA), F-33882 Villenave d'Ornon, France
| | - Vessela Atanasova
- INRAE, UR 1264 Mycology and Food Safety (MycSA), F-33882 Villenave d'Ornon, France
| | - Sylvain Chereau
- INRAE, UR 1264 Mycology and Food Safety (MycSA), F-33882 Villenave d'Ornon, France
| | - Christine Ducos
- INRAE, UR 1264 Mycology and Food Safety (MycSA), F-33882 Villenave d'Ornon, France
| | - Nathalie Gallegos
- INRAE, UR 1264 Mycology and Food Safety (MycSA), F-33882 Villenave d'Ornon, France
| | - Véronique Ortega
- Syngenta France SAS, Route de Vignolles lieu dit La Grangette, 32220 Lombez, France
| | - Nadia Ponts
- INRAE, UR 1264 Mycology and Food Safety (MycSA), F-33882 Villenave d'Ornon, France
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Shin KC, Lee J, Oh DK. Characterization of Arachidonate 5S-Lipoxygenase from Danio rerio with High Activity for the Production of 5S- and 7S-Hydroxy Polyunsaturated Fatty Acids. Appl Biochem Biotechnol 2023; 195:958-972. [PMID: 36251113 DOI: 10.1007/s12010-022-04150-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2022] [Indexed: 01/24/2023]
Abstract
A recombinant putative lipoxygenase (LOX) from Danio rerio (zebrafish), ALOX3c protein with 6-histidine tag, was purified using affinity chromatography, with a specific activity of 17.2 U mg-1 for arachidonic acid (AA). The molecular mass of the native ALOX3c was 156 kDa composed of a 78-kDa dimer by gel-filtration chromatography. The product obtained from the conversion of AA was identified as 5S-hydroxyeicosatetraenoic acid (5S-HETE) by HPLC and LC-MS/MS analyses. The specific activity and catalytic efficiency of the LOX from D. rerio for polyunsaturated fatty acids (PUFAs) followed the order AA (17.2 U mg-1, 1.96 s-1 μM-1) > docosahexaenoic acid (DHA, 13.6 U mg-1, 0.91 s-1 μM-1) > eicosapentaenoic acid (EPA, 10.5 U mg-1, 0.65 s-1 μM-1) and these values for AA were the highest among the 5S-LOXs reported to date. Based on identified products and substrate specificity, the enzyme is an AA 5S-LOX. The enzyme exhibited the maximal activity at pH 8.0 and 20 °C with 0.1 mM Zn2+ in the presence of 10 mM cysteine. Under these reaction conditions, 6.88 U mL-1 D. rerio 5S-LOX converted 1.0 mM of AA, EPA, and DHA to 0.91 mM 5S-HETE, 0.72 mM 5S-hydroxyeicosapentaenoic acid (5S-HEPE), and 0.68 mM 7S-hydroxydocosahexaenoic acid (7S-HDHA) in 25, 30, and 25 min, corresponding to molar conversion rates of 91, 72, and 68% and productivities of 2.18, 1.44, and 1.63 mM h-1, respectively. To the best of our knowledge, this study is the first to describe the bioconversion into 5S-HETE, 5S-HEPE, and 7S-HDHA for the application of biotechnological production.
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Affiliation(s)
- Kyung-Chul Shin
- Department of Integrative Bioscience and Biotechnology, Konkuk University, Seoul, 05029, Republic of Korea
| | - Jin Lee
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, 05029, Republic of Korea
| | - Deok-Kun Oh
- Department of Integrative Bioscience and Biotechnology, Konkuk University, Seoul, 05029, Republic of Korea. .,Department of Bioscience and Biotechnology, Konkuk University, Seoul, 05029, Republic of Korea.
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10
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Djian B, Feussner K, Herrfurth C, Zienkiewicz K, Hornung E, Feussner I. Plastidic membrane lipids are oxidized by a lipoxygenase in Lobosphaera incisa. FRONTIERS IN PLANT SCIENCE 2022; 13:1102215. [PMID: 36618660 PMCID: PMC9813749 DOI: 10.3389/fpls.2022.1102215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
Green microalgae can accumulate neutral lipids, as part of a general lipid remodeling mechanism under stress such as nitrogen starvation. Lobosphaera incisa is of special interest because of its unique TAG acyl chain composition, especially 20:4 (n-6) can reach up to 21% of dry weight after nitrogen starvation. In order to identify factors that may influence the accumulation of polyunsaturated fatty acids (PUFAs), we identified recently a linoleate 13-lipoxygenase (LiLOX). It shares highest identity with plastidic enzymes from vascular plants and is induced upon nitrogen starvation. Here, we confirmed the localization of LiLOX in the stroma of plastids via transient expression in epithelial onion cells. In order to further characterize this enzyme, we focused on the identification of the endogenous substrate of LiLOX. In this regard, an ex vivo enzymatic assay, coupled with non-targeted analysis via mass spectrometry allowed the identification of MGDG, DGDG and PC as three substrate candidates, later confirmed via in vitro assays. Further investigation revealed that LiLOX has preferences towards the lipid class MGDG, which seems in agreement with its localization in the galactolipid rich plastid. Altogether, this study shows the first characterization of plastidic LOX from green algae, showing preference for MGDGs. However, lipidomics analysis did neither reveal an endogenous LiLOX product nor the final end product of MGDG oxidation. Nevertheless, the latter is a key to understanding the role of this enzyme and since its expression is highest during the degradation of the plastidic membrane, it is tempting to assume its involvement in this process.
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Affiliation(s)
- Benjamin Djian
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
| | - Kirstin Feussner
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
- Goettingen Center for Molecular Biosciences (GZMB), Service Unit for Metabolomics and Lipidomics, University of Goettingen, Goettingen, Germany
| | - Cornelia Herrfurth
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
- Goettingen Center for Molecular Biosciences (GZMB), Service Unit for Metabolomics and Lipidomics, University of Goettingen, Goettingen, Germany
| | - Krzysztof Zienkiewicz
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
- Goettingen Center for Molecular Biosciences (GZMB), Service Unit for Metabolomics and Lipidomics, University of Goettingen, Goettingen, Germany
| | - Ellen Hornung
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
| | - Ivo Feussner
- Albrecht-von-Haller-Institute for Plant Sciences, Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
- Goettingen Center for Molecular Biosciences (GZMB), Service Unit for Metabolomics and Lipidomics, University of Goettingen, Goettingen, Germany
- Goettingen Center for Molecular Biosciences (GZMB), Department of Plant Biochemistry, University of Goettingen, Goettingen, Germany
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11
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Oliw EH. Diversity of the manganese lipoxygenase gene family - A mini-review. Fungal Genet Biol 2022; 163:103746. [PMID: 36283615 DOI: 10.1016/j.fgb.2022.103746] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 09/13/2022] [Accepted: 10/12/2022] [Indexed: 01/06/2023]
Abstract
Analyses of fungal genomes of escalate from biological and evolutionary investigations. The biochemical analyses of putative enzymes will inevitably lag behind and only a selection will be characterized. Plant-pathogenic fungi secrete manganese-lipoxygenases (MnLOX), which oxidize unsaturated fatty acids to hydroperoxides to support infection. Six MnLOX have been characterized so far including the 3D structures of these enzymes of the Rice blast and the Take-all fungi. The goal was to use this information to evaluate MnLOX-related gene transcripts to find informative specimens for further studies. Phylogenetic analysis, determinants of catalytic activities, and the C-terminal amino acid sequences divided 54 transcripts into three major subfamilies. The six MnLOX belonged to the same "prototype" subfamily with conserved residues in catalytic determinants and C-terminal sequences. The second subfamily retained the secretion mechanism, presumably necessary for uptake of Mn2+, but differed in catalytic determinants and by cysteine replacement of an invariant Leu residue for positioning ("clamping") of fatty acids. The third subfamily contrasted with alanine in the Gly/Ala switch for regiospecific oxidation and a minority contained unprecedented C-terminal sequences or lacked secretion signals. With these exceptions, biochemical analyses of transcripts of the three subfamilies appear to have reasonable prospects to find active enzymes.
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Affiliation(s)
- Ernst H Oliw
- Division of Biochemical Pharmacology, Department of Pharmaceutical Biosciences, Uppsala University, Box 591, SE 751 24 Uppsala, Sweden.
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