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Brofelth M, Städe LW, Ekstrand AI, Edfeldt LP, Kovačič R, Nielsen TT, Larsen KL, Duroux L, Wingren C. Site-specific photocoupling of p Bpa mutated scFv antibodies for use in affinity proteomics. Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics 2017; 1865:985-996. [DOI: 10.1016/j.bbapap.2017.03.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 03/13/2017] [Accepted: 03/20/2017] [Indexed: 12/26/2022]
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Städe LW, Nielsen TT, Duroux L, Wimmer R, Shimizu K, Larsen KL. Synthesis and surface grafting of a β-cyclodextrin dimer facilitating cooperative inclusion of 2,6-ANS. Beilstein J Org Chem 2015; 11:514-23. [PMID: 25977726 PMCID: PMC4419527 DOI: 10.3762/bjoc.11.58] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 04/15/2015] [Indexed: 11/26/2022] Open
Abstract
A novel β-cyclodextrin (β-CD) dimer was synthesized and surface-grafted by click chemistry onto azide-functionalized quartz surfaces in order to introduce the cooperative features of the β-CD dimer to solid surfaces. Using NMR and fluorescence spectroscopy, it is shown that the free β-CD dimer forms a 1:1 complex with the fluorescent guest molecule, 2-anilinonaphthalene-6-sulfonic acid (otherwise known not to form 1:2 complexes with parent β-CD), with an apparent association constant of 7300 M−1. Further, it is shown using total internal reflection fluorescence spectroscopy that the inclusion of the fluorescent guest into both cavities of the β-CD dimer is maintained when grafted onto a solid surface.
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Affiliation(s)
- Lars W Städe
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Frederik Bajers Vej 7H, DK-9220 Aalborg East, Denmark
| | - Thorbjørn T Nielsen
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Frederik Bajers Vej 7H, DK-9220 Aalborg East, Denmark
| | - Laurent Duroux
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Frederik Bajers Vej 7H, DK-9220 Aalborg East, Denmark
| | - Reinhard Wimmer
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Frederik Bajers Vej 7H, DK-9220 Aalborg East, Denmark
| | - Kyoko Shimizu
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus, Denmark
| | - Kim L Larsen
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Frederik Bajers Vej 7H, DK-9220 Aalborg East, Denmark
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Städe LW, Nielsen TT, Duroux L, Hinge M, Shimizu K, Gurevich L, Kristensen PK, Wingren C, Larsen KL. Nonfouling tunable βCD dextran polymer films for protein applications. ACS Appl Mater Interfaces 2015; 7:4160-4168. [PMID: 25639169 DOI: 10.1021/am508350r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Polymeric β-cyclodextrin (βCD) films tunable with respect to thickness and βCD content were prepared in order to develop a suitable platform, allowing for inclusion of nonpolar guest molecules in the βCD cavity, while suppressing nonspecific protein adsorption. The βCD films were synthesized from linear βCD dextran polymers, and grafted onto silicon oxide surfaces by "click" chemistry. Topographic and morphological characteristics are controllable by reaction conditions and polymer type, with average film heights from 2.5 to 12.5 nm. Reversible introduction of electrostatic charges in the βCD dextran by complex formation with 1-adamantanecarboxylic acid prior to surface grafting resulted in a thinner and denser film, presumably by decompaction of the polymers. Total internal reflection fluorescence spectroscopy (TIRF) was employed to evaluate the accessibility of βCD cavities to the fluorescent probe 2-anilinonaphthalene-6-sulfonic acid. Only a minor fraction of the βCD cavities was accessible in the thicker and less dense films; however, accessibility was largely improved with increased ionic strength using NaCl up to 1 M. Antifouling properties of the βCD dextran polymer films were assessed by TIRF real-time monitoring, using bovine serum albumin as a model protein, and showed a 5- to 10-fold reduction in nonspecific adsorption as compared to a bare quartz surface with the degree of reduction reflecting film thickness and interfacial polymer density.
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Affiliation(s)
- Lars W Städe
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University , Frederik Bajers Vej 7H, DK-9220 Aalborg East, Denmark
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Nielsen TT, Amiel C, Duroux L, Larsen KL, Städe LW, Wimmer R, Wintgens V. Formation of nanoparticles by cooperative inclusion between (S)-camptothecin-modified dextrans and β-cyclodextrin polymers. Beilstein J Org Chem 2015; 11:147-54. [PMID: 25670998 PMCID: PMC4311650 DOI: 10.3762/bjoc.11.14] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 12/11/2014] [Indexed: 12/01/2022] Open
Abstract
Novel (S)-camptothecin–dextran polymers were obtained by “click” grafting of azide-modified (S)-camptothecin and alkyne-modified dextrans. Two series based on 10 kDa and 70 kDa dextrans were prepared with a degree of substitution of (S)-camptothecin between 3.1 and 10.2%. The binding properties with β-cyclodextrin and β-cyclodextrin polymers were measured by isothermal titration calorimetry and fluorescence spectroscopy, showing no binding with β-cyclodextrin but high binding with β-cyclodextrin polymers. In aqueous solution nanoparticles were formed from association between the (S)-camptothecin–dextran polymers and the β-cyclodextrin polymers.
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Affiliation(s)
- Thorbjørn Terndrup Nielsen
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, 9000 Aalborg, Denmark
| | - Catherine Amiel
- Systèmes Polymères Complexes, ICMPE, CNRS and University Paris Est, 2 rue Henri Dunant, 94320 Thiais, France
| | - Laurent Duroux
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, 9000 Aalborg, Denmark
| | - Kim Lambertsen Larsen
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, 9000 Aalborg, Denmark
| | - Lars Wagner Städe
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, 9000 Aalborg, Denmark
| | - Reinhard Wimmer
- Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 57, 9000 Aalborg, Denmark
| | - Véronique Wintgens
- Systèmes Polymères Complexes, ICMPE, CNRS and University Paris Est, 2 rue Henri Dunant, 94320 Thiais, France
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Amiri S, Duroux L, Nielsen TT, Larsen KL. Preparation and characterization of a temperature-sensitive nonwoven poly(propylene) with increased affinity for guest molecules. J Appl Polym Sci 2014. [DOI: 10.1002/app.40497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Setareh Amiri
- Department of Biotechnology; Chemistry and Environmental Engineering, Aalborg University; Aalborg Denmark
| | - Laurent Duroux
- Department of Biotechnology; Chemistry and Environmental Engineering, Aalborg University; Aalborg Denmark
| | - Thorbjørn Terndrup Nielsen
- Department of Biotechnology; Chemistry and Environmental Engineering, Aalborg University; Aalborg Denmark
| | - Kim Lambertsen Larsen
- Department of Biotechnology; Chemistry and Environmental Engineering, Aalborg University; Aalborg Denmark
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Jensen RL, Städe LW, Wimmer R, Stensballe A, Duroux M, Larsen KL, Wingren C, Duroux L. Direct site-directed photocoupling of proteins onto surfaces coated with beta-cyclodextrins. Langmuir 2010; 26:11597-11604. [PMID: 20441154 DOI: 10.1021/la100950n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A method called Dock'n'Flash was developed to offer site-specific capture and direct UVA-induced photocoupling of recombinant proteins. The method involves the tagging of recombinant proteins with photoreactive p-benzoyl-L-phenylalanine (pBpa) by genetic engineering. The photoreactive pBpa tag is used for affinity capture of the recombinant protein by beta-cyclodextrin (beta-CD), which provides hydrogen atoms to be abstracted in the photocoupling process. To exemplify the method, a recombinant, folded, and active N27pBpa mutant of cutinase from Fusarium solani pisi was produced in E. coli. Insertion of pBpa was verified by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectroscopy. A molecular dynamic simulation, with water as solvent, showed high solvent accessibility of the pBpa benzophenone group in N27pBpa-cutinase mutant. The formation of an inclusion complex between the benzophenone group of N27pBpa-cutinase and beta-CD was shown, and an apparent K(d) of 1.65 mM was determined using (1)H NMR. Photocoupling of beta-CD to N27pBpa-cutinase in a 1:1 ratio, upon UVA irradiation at 360 +/- 20 nm, was shown by MALDI-TOF mass spectroscopy. UVA photoimmobilization of N27pBpa-cutinase on quartz slides coated with beta-CD was achieved from liquid or dry films by total internal reflection fluorescence (TIRF). The Dock'n'Flash method offers a solution for direct photocoupling and patterning of recombinant proteins onto surfaces with site-specific attachment.
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Affiliation(s)
- Rasmus L Jensen
- Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4a, DK-9220 Aalborg, Denmark
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Abstract
Our group has previously shown that biomolecules containing disulfide bridges in close proximity to aromatic residues can be immobilized, through covalent bonds, onto thiol derivatized surfaces upon UV excitation of the aromatic residue(s). We have also previously shown that our new technology can be used to print arrays of biomolecules and to immobilize biomolecules according to any specific pattern on a planar substrates with micrometer scale resolution. In this paper we show that we can immobilize proteins according to diffraction patterns of UV light. We also show that the feature size of the immobilized patterns can be as small as the diffraction limit for the excitation light, and that the immobilized patterns correspond to the diffraction pattern used to generate it. The flexibility of this new technology will in principle make it possible to create any pattern of biomolecules onto a substrate, which can be generated by a UV diffraction pattern. Such patterns can have sub-micron feature sizes and could therefore be of great relevance for present and future nanotechnological applications.
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Affiliation(s)
- Esben Skovsen
- NanoBiotechnology Group, Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4A, Aalborg 9000, Denmark
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Neves-Petersen MT, Duroux M, Skovsen E, Duroux L, Petersen SB. Printing novel molecular architectures with micrometer resolution using light. J Nanosci Nanotechnol 2009; 9:3372-3381. [PMID: 19504856 DOI: 10.1166/jnn.2009.ns04] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In this paper we present a new photonic technology and demonstrate that it allows for precise immobilisation of proteins to sensor surfaces. The new technology secures spatially controlled molecular immobilisation since the immobilisation of each molecule to a support surface can be limited to the focal point of the UV laser beam, with dimensions as small as a few micrometers. We have demonstrated that we are not limited to immobilising molecules according to conventional patterns like microarrays. We can immobilise molecules on a surface with any arbitrary pattern. The different illumination/immobilisation setups presented expand the capabilities and usefulness of the new technology, since immobilisation can both be achieved with a laser system and with an affordable Xenon lamp setup. Of extreme relevance to the success of this technology is the precise knowledge of photon flux, energy flux, total number of photons per area, fluency and peak intensity. The expected resolution, taken into account the size of the focused laser beam, the precision of translation stage, and the scanner resolution of our laser scanner is in good agreement with the experimental resolution obtained. The flexibility of this new technology allows creating any patterns/ structures of molecules, with micrometer resolution, thus being of relevance for present and future nanotechnological applications.
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Affiliation(s)
- Maria Teresa Neves-Petersen
- NanoBiotechnology Group, Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4A, Aalborg, Denmark
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Oeemig JS, Jørgensen ML, Hansen MS, Petersen EI, Duroux L, Wimmer R. Backbone and sidechain 1H, 13C and 15N resonance assignments of the human brain-type fatty acid binding protein (FABP7) in its apo form and the holo forms binding to DHA, oleic acid, linoleic acid and elaidic acid. Biomol NMR Assign 2009; 3:89-93. [PMID: 19636954 DOI: 10.1007/s12104-009-9148-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Accepted: 02/10/2009] [Indexed: 05/28/2023]
Abstract
In this manuscript, we present the backbone and side chain assignments of human brain-type fatty acid binding protein, also known as FABP7, in its apo form and in four different holo forms, bound to DHA, oleic acid, linoleic acid and elaidic acid.
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Affiliation(s)
- Jesper S Oeemig
- Department of Chemistry, Biotechnology and Environmental Engineering, Aalborg University, Sohngaardsholmsvej 49, 9000, Aalborg, Denmark
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Duroux M, Skovsen E, Neves-Petersen MT, Duroux L, Gurevich L, Petersen SB. Light-induced immobilisation of biomolecules as an attractive alternative to micro-droplet dispensing-based arraying technologies. Proteomics 2008. [DOI: 10.1002/pmic.200890012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Duroux M, Skovsen E, Neves-Petersen MT, Duroux L, Gurevich L, Petersen SB. Light-induced immobilisation of biomolecules as an attractive alternative to microdroplet dispensing-based arraying technologies. Proteomics 2007; 7:3491-9. [PMID: 17907272 DOI: 10.1002/pmic.200700472] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The present work shows how UV 'light-induced molecular immobilisation' (LIMI) of biomolecules onto thiol reactive surfaces can be used to make biosensors, without the need for traditional microdispensing technologies. Using 'LIMI,' arrays of biomolecules can be created with a high degree of reproducibility. This technology can be used to circumvent the need for often expensive nano/microdispensing technologies. The ultimate size of the immobilised spots is defined by the focal area of the UV beam, which for a diffraction-limited beam can be less than 1 microm in diameter. LIMI has the added benefit that the immobilised molecules will be spatially oriented and covalently bound to the surface. The activity of the sensor molecules is retained. Antibody sensor arrays made using LIMI demonstrated successful antigen binding. In addition, the pattern of immobilised molecules on the surface is not restricted to conventional array formats. The ultimate consequence of the LIMI is that it is possible to write complex protein patterns using bitmaps at high resolution onto substrates. Thus, LIMI of biomolecules provides a new technological platform for biomolecular immobilisation and the potential for replacing present microdispensing arraying technologies.
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Affiliation(s)
- Meg Duroux
- NanoBiotechnology Group, Department of Physics and Nanotechnology, Aalborg University, Aalborg, Denmark
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Poulsen KR, Sørensen TK, Duroux L, Petersen EI, Petersen SB, Wimmer R. The Interaction of Fusarium solani pisi Cutinase with Long Chain Spin Label Esters. Biochemistry 2006; 45:9163-71. [PMID: 16866362 DOI: 10.1021/bi060329i] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We here present a study of the interaction between the Fusarium solani pisi cutinase mutant S120A and spin-labeled 4,4-dimethyloxazoline-N-oxyl-(DOXYL)-stearoyl-glycerol substrates in a micellar system. The interaction is detected by NMR measuring changes in chemical shift for 1H and 15N as well as relaxation parameters for backbone 1H (T1) and 15N (T1, T2) atoms as well as for side chain methyl groups 1H (T1). The detected interaction shows a weak binding of cutinase to the lipid micelles. Structural and mobility changes are located inside and around the active site, its flanking loops, and the oxyanion hole, respectively. Relaxation changes in the amino acid pairs Ser 92, Ala 93 and Thr 173, Gly 174 positioned at the edge of each of the active site flanking loops make these residues prime candidates for hinges, allowing for structural rearrangement during substrate binding. The cutinase mutant S120A used carries a 15 amino acid pro-peptide; the significance of this pro-peptide was so far undetermined. We show here that the pro-peptide is affected by the presence of the micellar substrate. Relaxation enhancements indicative of spatial proximity between the DOXYL group in the lipid chain and some hydrophobic residues surrounding the active site could be found.
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Affiliation(s)
- Kristian R Poulsen
- Biostructure and Protein Engineering Group, Department of Physics and Nanotechnology, Aalborg University, DK-9220 Aalborg, Denmark
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Abstract
The 73 class III peroxidase genes in Arabidopsis thaliana were used for surveying the evolutionary relationships among peroxidases in the plant kingdom. In Arabidopsis, the 73 genes were clustered in robust similarity groups. Comparison to peroxidases from other angiosperms showed that the diversity observed in Arabidopsis preceded the radiation of dicots, whereas some clusters were absent from grasses. Grasses contained some unique peroxidase clusters not seen in dicot plants. We found peroxidases in other major groups of land plants but not in algae. This might indicate that the class III peroxidase gene family appeared with the colonization of land by plants. The present survey may be used as a rational basis for further investigating the functional roles of class III peroxidases.
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Affiliation(s)
- Laurent Duroux
- Department of Life Sciences, Aalborg University, Sohngaardsholmsvej 49, DK-9000 Aalborg, Denmark.
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Welinder KG, Justesen AF, Kjaersgård IVH, Jensen RB, Rasmussen SK, Jespersen HM, Duroux L. Structural diversity and transcription of class III peroxidases from Arabidopsis thaliana. Eur J Biochem 2002; 269:6063-81. [PMID: 12473102 DOI: 10.1046/j.1432-1033.2002.03311.x] [Citation(s) in RCA: 175] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Understanding peroxidase function in plants is complicated by the lack of substrate specificity, the high number of genes, their diversity in structure and our limited knowledge of peroxidase gene transcription and translation. In the present study we sequenced expressed sequence tags (ESTs) encoding novel heme-containing class III peroxidases from Arabidopsis thaliana and annotated 73 full-length genes identified in the genome. In total, transcripts of 58 of these genes have now been observed. The expression of individual peroxidase genes was assessed in organ-specific EST libraries and compared to the expression of 33 peroxidase genes which we analyzed in whole plants 3, 6, 15, 35 and 59 days after sowing. Expression was assessed in root, rosette leaf, stem, cauline leaf, flower bud and cell culture tissues using the gene-specific and highly sensitive reverse transcriptase-polymerase chain reaction (RT-PCR). We predicted that 71 genes could yield stable proteins folded similarly to horseradish peroxidase (HRP). The putative mature peroxidases derived from these genes showed 28-94% amino acid sequence identity and were all targeted to the endoplasmic reticulum by N-terminal signal peptides. In 20 peroxidases these signal peptides were followed by various N-terminal extensions of unknown function which are not present in HRP. Ten peroxidases showed a C-terminal extension indicating vacuolar targeting. We found that the majority of peroxidase genes were expressed in root. In total, class III peroxidases accounted for an impressive 2.2% of root ESTs. Rather few peroxidases showed organ specificity. Most importantly, genes expressed constitutively in all organs and genes with a preference for root represented structurally diverse peroxidases (< 70% sequence identity). Furthermore, genes appearing in tandem showed distinct expression profiles. The alignment of 73 Arabidopsis peroxidase sequences provides an easy access to the identification of orthologous peroxidases in other plant species and will provide a common platform for combining knowledge of peroxidase structure and function relationships obtained in various species.
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Affiliation(s)
- Karen G Welinder
- Department of Protein Chemistry, University of Copenhagen, Denmark.
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Duroux L, Delmotte FM, Lancelin JM, Kéravis G, Jay-Allemand C. Insight into naphthoquinone metabolism: beta-glucosidase-catalysed hydrolysis of hydrojuglone beta-D-glucopyranoside. Biochem J 1998; 333 ( Pt 2):275-83. [PMID: 9657966 PMCID: PMC1219583 DOI: 10.1042/bj3330275] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In plants, the naphthoquinone juglone is known to be involved in pathogenic defence mechanisms, but it may also take part in plant developmental processes. This naphthoquinone can accumulate in a glycosylated form, namely hydrojuglone beta-d-glucopyranoside. The structural configuration of this compound was shown to be 1, 5-dihydroxy-4-naphthalenyl-beta-d-glucopyranoside by means of MS, NMR and nuclear Overhauser effect spectroscopy analyses. A hydrojuglone beta-d-glucopyranoside beta-glucosidase (EC 3.2.1.21) was purified to homogeneity from Juglans regia L. The enzyme catalysed the release of juglone from hydrojuglone beta-d-glucopyranoside with high specificity and showed Michaelis-Menten kinetics with Km=0.62 mM and Vmax=14.5 microkat/mg of protein. This enzyme also showed a higher activity towards beta-d-fucosyl than beta-d-glucosyl bonds. The purified enzyme had an apparent Mr of 64000 by SDS/PAGE and a pI 8.9 by isoelectrofocusing PAGE. The purified enzyme was inhibited by several bivalent cations, such as Cu2+, Fe2+, Hg2+, and by d-glucono-1,5-lactone, showing non-competitive inhibition of the mixed type.
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Affiliation(s)
- L Duroux
- Station d'Amélioration des Arbres Forestiers, I.N.R.A.-Orléans, 45160 Ardon, France
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