Publications
2004 |
Przykorska, A; Solecka, K; Olszak, K; Keith, G; Nawrot, B; Kuligowska, E Wheat (Triticum vulgare) chloroplast nuclease ChSI exhibits 5' flap structure-specific endonuclease activity Article de journal Biochemistry, 43 (35), p. 11283-94, 2004, (0006-2960 Journal Article). Résumé | BibTeX | Étiquettes: &, Acid, Catalysis, Chloroplasts/*enzymology, Conformation, Desorption-Ionization, DNA, Endonucleases/*chemistry/isolation, Exonucleases/chemistry/metabolism, Flap, Gov't, Hydrolysis, KEITH, Kinetics, Laser, Mass, Matrix-Assisted, Non-U.S., Nucleic, Oligonucleotides/chemical, Plant/chemistry/metabolism, purification/*metabolism, Relationship, Single-Stranded/chemistry/metabolism, Specificity, Spectrometry, Structure-Activity, Substrate, Support, synthesis/metabolism, Thermodynamics, Triticum/*enzymology @article{, title = {Wheat (Triticum vulgare) chloroplast nuclease ChSI exhibits 5' flap structure-specific endonuclease activity}, author = { A. Przykorska and K. Solecka and K. Olszak and G. Keith and B. Nawrot and E. Kuligowska}, year = {2004}, date = {2004-01-01}, journal = {Biochemistry}, volume = {43}, number = {35}, pages = {11283-94}, abstract = {The structure-specific ChSI nuclease from wheat (Triticum vulgare) chloroplast stroma has been previously purified and characterized in our laboratory. It is a single-strand-specific DNA and RNA endonuclease. Although the enzyme has been initially characterized and used as a structural probe, its biological function is still unknown. Localization of the ChSI enzyme inside chloroplasts, possessing their own DNA that is generally highly exposed to UV light and often affected by numerous redox reactions and electron transfer processes, might suggest, however, that this enzyme could be involved in DNA repair. The repair of some types of DNA damage has been shown to proceed through branched DNA intermediates which are substrates for the structure-specific DNA endonucleases. Thus we tested the substrate specificity of ChSI endonuclease toward various branched DNAs containing 5' flap, 5' pseudoflap, 3' pseudoflap, or single-stranded bulged structural motifs. It appears that ChSI has a high 5' flap structure-specific endonucleolytic activity. The catalytic efficiency (k(cat)/K(M)) of the enzyme is significantly higher for the 5' flap substrate than for single-stranded DNA. The ChSI 5' flap activity was inhibited by high concentrations of Mg(2+), Mn(2+), Zn(2+), or Ca(2+). However, low concentrations of divalent cations could restore the loss of ChSI activity as a consequence of EDTA pretreatment. In contrast to other known 5' flap nucleases, the chloroplast enzyme ChSI does not possess any 5'-->3' exonuclease activity on double-stranded DNA. Therefore, we conclude that ChSI is a 5' flap structure-specific endonuclease with nucleolytic activity toward single-stranded substrates.}, note = {0006-2960 Journal Article}, keywords = {&, Acid, Catalysis, Chloroplasts/*enzymology, Conformation, Desorption-Ionization, DNA, Endonucleases/*chemistry/isolation, Exonucleases/chemistry/metabolism, Flap, Gov't, Hydrolysis, KEITH, Kinetics, Laser, Mass, Matrix-Assisted, Non-U.S., Nucleic, Oligonucleotides/chemical, Plant/chemistry/metabolism, purification/*metabolism, Relationship, Single-Stranded/chemistry/metabolism, Specificity, Spectrometry, Structure-Activity, Substrate, Support, synthesis/metabolism, Thermodynamics, Triticum/*enzymology}, pubstate = {published}, tppubtype = {article} } The structure-specific ChSI nuclease from wheat (Triticum vulgare) chloroplast stroma has been previously purified and characterized in our laboratory. It is a single-strand-specific DNA and RNA endonuclease. Although the enzyme has been initially characterized and used as a structural probe, its biological function is still unknown. Localization of the ChSI enzyme inside chloroplasts, possessing their own DNA that is generally highly exposed to UV light and often affected by numerous redox reactions and electron transfer processes, might suggest, however, that this enzyme could be involved in DNA repair. The repair of some types of DNA damage has been shown to proceed through branched DNA intermediates which are substrates for the structure-specific DNA endonucleases. Thus we tested the substrate specificity of ChSI endonuclease toward various branched DNAs containing 5' flap, 5' pseudoflap, 3' pseudoflap, or single-stranded bulged structural motifs. It appears that ChSI has a high 5' flap structure-specific endonucleolytic activity. The catalytic efficiency (k(cat)/K(M)) of the enzyme is significantly higher for the 5' flap substrate than for single-stranded DNA. The ChSI 5' flap activity was inhibited by high concentrations of Mg(2+), Mn(2+), Zn(2+), or Ca(2+). However, low concentrations of divalent cations could restore the loss of ChSI activity as a consequence of EDTA pretreatment. In contrast to other known 5' flap nucleases, the chloroplast enzyme ChSI does not possess any 5'-->3' exonuclease activity on double-stranded DNA. Therefore, we conclude that ChSI is a 5' flap structure-specific endonuclease with nucleolytic activity toward single-stranded substrates. |
2003 |
Thouzeau, Cécile; Maho, Yvon Le; Froget, Guillaume; Sabatier, Laurence; Bohec, Céline Le; Hoffmann, Jules A; Bulet, Philippe Spheniscins, avian beta-defensins in preserved stomach contents of the king penguin, Aptenodytes patagonicus Article de journal J. Biol. Chem., 278 (51), p. 51053–51058, 2003, ISSN: 0021-9258. Résumé | Liens | BibTeX | Étiquettes: Animals, Antimicrobial Cationic Peptides, bacteria, beta-Defensins, Birds, Feeding Behavior, Fungi, Gastrointestinal Contents, hoffmann, M3i, Male, Mass, Matrix-Assisted Laser Desorption-Ionization, Protein Isoforms, Sequence Alignment, Spectrometry @article{thouzeau_spheniscins_2003, title = {Spheniscins, avian beta-defensins in preserved stomach contents of the king penguin, Aptenodytes patagonicus}, author = {Cécile Thouzeau and Yvon Le Maho and Guillaume Froget and Laurence Sabatier and Céline Le Bohec and Jules A Hoffmann and Philippe Bulet}, doi = {10.1074/jbc.M306839200}, issn = {0021-9258}, year = {2003}, date = {2003-12-01}, journal = {J. Biol. Chem.}, volume = {278}, number = {51}, pages = {51053--51058}, abstract = {During the last part of egg incubation in king penguins, the male can preserve undigested food in the stomach for several weeks. This ensures survival of the newly hatched chick, in cases where the return of the foraging female from the sea is delayed. In accordance with the characterization of stress-induced bacteria, we demonstrate the occurrence of strong antimicrobial activities in preserved stomach contents. We isolated and fully characterized two isoforms of a novel 38-residue antimicrobial peptide (AMP), spheniscin, belonging to the beta-defensin subfamily. Spheniscin concentration was found to strongly increase during the period of food storage. Using a synthetic version of one of two spheniscin isoforms, we established that this peptide has a broad activity spectrum, affecting the growth of both pathogenic bacteria and fungi. Altogether, our data suggest that spheniscins and other, not yet identified, antimicrobial substances may play a role in the long term preservation of stored food in the stomach of king penguins.}, keywords = {Animals, Antimicrobial Cationic Peptides, bacteria, beta-Defensins, Birds, Feeding Behavior, Fungi, Gastrointestinal Contents, hoffmann, M3i, Male, Mass, Matrix-Assisted Laser Desorption-Ionization, Protein Isoforms, Sequence Alignment, Spectrometry}, pubstate = {published}, tppubtype = {article} } During the last part of egg incubation in king penguins, the male can preserve undigested food in the stomach for several weeks. This ensures survival of the newly hatched chick, in cases where the return of the foraging female from the sea is delayed. In accordance with the characterization of stress-induced bacteria, we demonstrate the occurrence of strong antimicrobial activities in preserved stomach contents. We isolated and fully characterized two isoforms of a novel 38-residue antimicrobial peptide (AMP), spheniscin, belonging to the beta-defensin subfamily. Spheniscin concentration was found to strongly increase during the period of food storage. Using a synthetic version of one of two spheniscin isoforms, we established that this peptide has a broad activity spectrum, affecting the growth of both pathogenic bacteria and fungi. Altogether, our data suggest that spheniscins and other, not yet identified, antimicrobial substances may play a role in the long term preservation of stored food in the stomach of king penguins. |
Sabatier, Laurence; Jouanguy, Emmanuelle; Dostert, Catherine; Zachary, Daniel; Dimarcq, Jean-Luc; Bulet, Philippe; Imler, Jean-Luc Pherokine-2 and -3 Article de journal European journal of biochemistry / FEBS, 270 (16), p. 3398–3407, 2003, ISSN: 0014-2956. Résumé | BibTeX | Étiquettes: Animals, Antibody Formation, Base Sequence, Hemolymph, imler, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Spectrometry @article{sabatier_pherokine-2_2003, title = {Pherokine-2 and -3}, author = {Laurence Sabatier and Emmanuelle Jouanguy and Catherine Dostert and Daniel Zachary and Jean-Luc Dimarcq and Philippe Bulet and Jean-Luc Imler}, issn = {0014-2956}, year = {2003}, date = {2003-01-01}, journal = {European journal of biochemistry / FEBS}, volume = {270}, number = {16}, pages = {3398--3407}, abstract = {Drosophila is a powerful model system to study the regulatory and effector mechanisms of innate immunity. To identify molecules induced in the course of viral infection in this insect, we have developed a model based on intrathoracic injection of the picorna-like Drosophila C virus (DCV). We have used MALDI-TOF mass spectrometry to compare the hemolymph of DCV infected flies and control flies. By contrast with the strong humoral response triggered by injection of bacteria or fungal spores, we have identified only one molecule induced in the hemolymph of virus infected flies. This molecule, pherokine-2 (Phk-2), is related to OS-D/A10 (Phk-1), which was previously characterized as a putative odor/pheromone binding protein specifically expressed in antennae. The virus-induced molecule is also similar to the product of the gene CG9358 (Phk-3), which is induced by septic injury. Both Phk-2 and Phk-3 are strongly expressed during metamorphosis, suggesting that they may participate in tissue-remodeling.}, keywords = {Animals, Antibody Formation, Base Sequence, Hemolymph, imler, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Spectrometry}, pubstate = {published}, tppubtype = {article} } Drosophila is a powerful model system to study the regulatory and effector mechanisms of innate immunity. To identify molecules induced in the course of viral infection in this insect, we have developed a model based on intrathoracic injection of the picorna-like Drosophila C virus (DCV). We have used MALDI-TOF mass spectrometry to compare the hemolymph of DCV infected flies and control flies. By contrast with the strong humoral response triggered by injection of bacteria or fungal spores, we have identified only one molecule induced in the hemolymph of virus infected flies. This molecule, pherokine-2 (Phk-2), is related to OS-D/A10 (Phk-1), which was previously characterized as a putative odor/pheromone binding protein specifically expressed in antennae. The virus-induced molecule is also similar to the product of the gene CG9358 (Phk-3), which is induced by septic injury. Both Phk-2 and Phk-3 are strongly expressed during metamorphosis, suggesting that they may participate in tissue-remodeling. |
2002 |
Ligoxygakis, Petros; Bulet, Philippe; Reichhart, Jean-Marc Critical evaluation of the role of the Toll-like receptor 18-Wheeler in the host defense of Drosophila Article de journal EMBO Rep., 3 (7), p. 666–673, 2002, ISSN: 1469-221X. Résumé | Liens | BibTeX | Étiquettes: Animals, Anti-Bacterial Agents, Antimicrobial Cationic Peptides, Cell Adhesion Molecules, Fat Body, Gene Expression Regulation, Genes, Immunohistochemistry, Immunologic, Insect, Insect Proteins, Larva, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Membrane Proteins, Receptors, reichhart, Reporter, Spectrometry, Transgenes @article{ligoxygakis_critical_2002, title = {Critical evaluation of the role of the Toll-like receptor 18-Wheeler in the host defense of Drosophila}, author = {Petros Ligoxygakis and Philippe Bulet and Jean-Marc Reichhart}, doi = {10.1093/embo-reports/kvf130}, issn = {1469-221X}, year = {2002}, date = {2002-01-01}, journal = {EMBO Rep.}, volume = {3}, number = {7}, pages = {666--673}, abstract = {Essential aspects of innate immune responses to microbial infections appear to be conserved between insects and mammals. In particular, in both groups, transmembrane receptors of the Toll superfamily play a crucial role in activating immune defenses. The Drosophila Toll family member 18-Wheeler had been proposed to sense Gram-negative infection and direct selective expression of peptides active against Gram-negative bacteria. Here we re-examine the role of 18-Wheeler and show that in adults it is dispensable for immune responses. In larvae, 18wheeler is required for normal fat body development, and in mutant larvae induction of all antimicrobial peptide genes, and not only of those directed against Gram-negative bacteria, is compromised. 18-Wheeler does not qualify as a pattern recognition receptor of Gram-negative bacteria.}, keywords = {Animals, Anti-Bacterial Agents, Antimicrobial Cationic Peptides, Cell Adhesion Molecules, Fat Body, Gene Expression Regulation, Genes, Immunohistochemistry, Immunologic, Insect, Insect Proteins, Larva, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Membrane Proteins, Receptors, reichhart, Reporter, Spectrometry, Transgenes}, pubstate = {published}, tppubtype = {article} } Essential aspects of innate immune responses to microbial infections appear to be conserved between insects and mammals. In particular, in both groups, transmembrane receptors of the Toll superfamily play a crucial role in activating immune defenses. The Drosophila Toll family member 18-Wheeler had been proposed to sense Gram-negative infection and direct selective expression of peptides active against Gram-negative bacteria. Here we re-examine the role of 18-Wheeler and show that in adults it is dispensable for immune responses. In larvae, 18wheeler is required for normal fat body development, and in mutant larvae induction of all antimicrobial peptide genes, and not only of those directed against Gram-negative bacteria, is compromised. 18-Wheeler does not qualify as a pattern recognition receptor of Gram-negative bacteria. |
1998 |
Uttenweiler-Joseph, S; Moniatte, M; Lagueux, Marie; Dorsselaer, Van A; Hoffmann, Jules A; Bulet, Philippe Differential display of peptides induced during the immune response of Drosophila: a matrix-assisted laser desorption ionization time-of-flight mass spectrometry study Article de journal Proc. Natl. Acad. Sci. U.S.A., 95 (19), p. 11342–11347, 1998, ISSN: 0027-8424. Résumé | BibTeX | Étiquettes: Animals, bacteria, Chromatography, Cloning, Hemolymph, High Pressure Liquid, hoffmann, Immunity, Insect Proteins, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, messenger, Molecular, Peptides, Protein Precursors, RNA, Sequence Analysis, Spectrometry, Time Factors @article{uttenweiler-joseph_differential_1998, title = {Differential display of peptides induced during the immune response of Drosophila: a matrix-assisted laser desorption ionization time-of-flight mass spectrometry study}, author = {S Uttenweiler-Joseph and M Moniatte and Marie Lagueux and Van A Dorsselaer and Jules A Hoffmann and Philippe Bulet}, issn = {0027-8424}, year = {1998}, date = {1998-09-01}, journal = {Proc. Natl. Acad. Sci. U.S.A.}, volume = {95}, number = {19}, pages = {11342--11347}, abstract = {We have developed an approach based on a differential mass spectrometric analysis to detect molecules induced during the immune response of Drosophila, regardless of their biological activities. For this, we have applied directly matrix-assisted laser desorption/ionization MS to hemolymph samples from individual flies before and after an immune challenge. This method provided precise information on the molecular masses of immune-induced molecules and allowed the detection, in the molecular range of 1.5-11 kDa, of 24 Drosophila immune-induced molecules (DIMs). These molecules are all peptides, and four correspond to already characterized antimicrobial peptides. We have further analyzed the induction of the various peptides by immune challenge in wild-type flies and in mutants with a compromised antimicrobial response. We also describe a methodology combining matrix-assisted laser desorption ionization time-of-flight MS, HPLC, and Edman degradation, which yielded the peptide sequence of three of the DIMs. Finally, molecular cloning and Northern blot analyses revealed that one of the DIMs is produced as a prepropeptide and is inducible on a bacterial challenge.}, keywords = {Animals, bacteria, Chromatography, Cloning, Hemolymph, High Pressure Liquid, hoffmann, Immunity, Insect Proteins, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, messenger, Molecular, Peptides, Protein Precursors, RNA, Sequence Analysis, Spectrometry, Time Factors}, pubstate = {published}, tppubtype = {article} } We have developed an approach based on a differential mass spectrometric analysis to detect molecules induced during the immune response of Drosophila, regardless of their biological activities. For this, we have applied directly matrix-assisted laser desorption/ionization MS to hemolymph samples from individual flies before and after an immune challenge. This method provided precise information on the molecular masses of immune-induced molecules and allowed the detection, in the molecular range of 1.5-11 kDa, of 24 Drosophila immune-induced molecules (DIMs). These molecules are all peptides, and four correspond to already characterized antimicrobial peptides. We have further analyzed the induction of the various peptides by immune challenge in wild-type flies and in mutants with a compromised antimicrobial response. We also describe a methodology combining matrix-assisted laser desorption ionization time-of-flight MS, HPLC, and Edman degradation, which yielded the peptide sequence of three of the DIMs. Finally, molecular cloning and Northern blot analyses revealed that one of the DIMs is produced as a prepropeptide and is inducible on a bacterial challenge. |
Bulet, Philippe; Uttenweiler-Joseph, S; Moniatte, M; Dorsselaer, Van A; Hoffmann, Jules A Differential display of peptides induced during the immune response of Drosophila: a matrix-assisted laser desorption ionization time-of-flight mass spectrometry study Article de journal J. Protein Chem., 17 (6), p. 528–529, 1998, ISSN: 0277-8033. BibTeX | Étiquettes: Animals, Anti-Infective Agents, hoffmann, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Peptide Biosynthesis, Peptides, Spectrometry @article{bulet_differential_1998, title = {Differential display of peptides induced during the immune response of Drosophila: a matrix-assisted laser desorption ionization time-of-flight mass spectrometry study}, author = {Philippe Bulet and S Uttenweiler-Joseph and M Moniatte and Van A Dorsselaer and Jules A Hoffmann}, issn = {0277-8033}, year = {1998}, date = {1998-08-01}, journal = {J. Protein Chem.}, volume = {17}, number = {6}, pages = {528--529}, keywords = {Animals, Anti-Infective Agents, hoffmann, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Peptide Biosynthesis, Peptides, Spectrometry}, pubstate = {published}, tppubtype = {article} } |
Taguchi, S; Bulet, Philippe; Hoffmann, Jules A A novel insect defensin from the ant Formica rufa Article de journal Biochimie, 80 (4), p. 343–346, 1998, ISSN: 0300-9084. Résumé | BibTeX | Étiquettes: Amino Acid, Animals, Anti-Bacterial Agents, Ants, Chromatography, High Pressure Liquid, hoffmann, Insect Proteins, insects, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Protein Structure, Secondary, Sequence Alignment, Sequence Homology, Spectrometry @article{taguchi_novel_1998, title = {A novel insect defensin from the ant Formica rufa}, author = {S Taguchi and Philippe Bulet and Jules A Hoffmann}, issn = {0300-9084}, year = {1998}, date = {1998-04-01}, journal = {Biochimie}, volume = {80}, number = {4}, pages = {343--346}, abstract = {By combination of size exclusion and reversed-phase chromatography, we have isolated a novel member of insect defensin-type antimicrobial peptides from the entire bodies of bacteria-challenged Formica rufa (hymenoptera, formicidae). The molecular mass of the purified peptide was estimated to be 4120.42 by matrix-assisted laser desorption/ionization-time of flight/mass spectrometry. Sequence analysis revealed that this peptide consisted of 40 amino acid residues with six cysteines engaged in the formation of three intramolecular disulfide bridges. This peptide is unique among the arthropod defensins in terms of the presence of asparatic acid and alanine at position 33 and as C-terminal residue, respectively. In addition, this novel defensin from Formica rufa has the particularity to have no C-terminal extension in contrast to those reported for other hymenoptera defensins.}, keywords = {Amino Acid, Animals, Anti-Bacterial Agents, Ants, Chromatography, High Pressure Liquid, hoffmann, Insect Proteins, insects, M3i, Mass, Matrix-Assisted Laser Desorption-Ionization, Protein Structure, Secondary, Sequence Alignment, Sequence Homology, Spectrometry}, pubstate = {published}, tppubtype = {article} } By combination of size exclusion and reversed-phase chromatography, we have isolated a novel member of insect defensin-type antimicrobial peptides from the entire bodies of bacteria-challenged Formica rufa (hymenoptera, formicidae). The molecular mass of the purified peptide was estimated to be 4120.42 by matrix-assisted laser desorption/ionization-time of flight/mass spectrometry. Sequence analysis revealed that this peptide consisted of 40 amino acid residues with six cysteines engaged in the formation of three intramolecular disulfide bridges. This peptide is unique among the arthropod defensins in terms of the presence of asparatic acid and alanine at position 33 and as C-terminal residue, respectively. In addition, this novel defensin from Formica rufa has the particularity to have no C-terminal extension in contrast to those reported for other hymenoptera defensins. |
1989 |
Rosenthal, G A; Reichhart, Jean-Marc; Hoffmann, Jules A L-canavanine incorporation into vitellogenin and macromolecular conformation Article de journal J. Biol. Chem., 264 (23), p. 13693–13696, 1989, ISSN: 0021-9258. Résumé | BibTeX | Étiquettes: Animals, Antibodies, Canavanine, fluorescence, Grasshoppers, hoffmann, M3i, Monoclonal, Protein Conformation, reichhart, Spectrometry, Vitellogenins @article{rosenthal_l-canavanine_1989, title = {L-canavanine incorporation into vitellogenin and macromolecular conformation}, author = {G A Rosenthal and Jean-Marc Reichhart and Jules A Hoffmann}, issn = {0021-9258}, year = {1989}, date = {1989-01-01}, journal = {J. Biol. Chem.}, volume = {264}, number = {23}, pages = {13693--13696}, abstract = {L-Canavanine is a potentially deleterious arginine antimetabolite whose toxicity is expressed in canavanine-sensitive organisms ranging from viruses to humans. Canavanine, a substrate for arginyl-tRNA synthetase, is incorporated into nascent polypeptide chains in place of arginine. This substitution results in the production of structurally aberrant, canavanyl proteins. Chemical, physical, and immunological studies of native and canavanine-containing vitellogenin obtained from female migratory locusts (Locusta migratoria migratorioides (Orthoptera] provide the first experimental evidence that canavanine can disrupt the tertiary and/or quaternary structure that yields the three-dimensional conformation unique to the protein. These findings enhance our understanding of the biochemical basis for canavanine's antimetabolic and potent insecticidal properties.}, keywords = {Animals, Antibodies, Canavanine, fluorescence, Grasshoppers, hoffmann, M3i, Monoclonal, Protein Conformation, reichhart, Spectrometry, Vitellogenins}, pubstate = {published}, tppubtype = {article} } L-Canavanine is a potentially deleterious arginine antimetabolite whose toxicity is expressed in canavanine-sensitive organisms ranging from viruses to humans. Canavanine, a substrate for arginyl-tRNA synthetase, is incorporated into nascent polypeptide chains in place of arginine. This substitution results in the production of structurally aberrant, canavanyl proteins. Chemical, physical, and immunological studies of native and canavanine-containing vitellogenin obtained from female migratory locusts (Locusta migratoria migratorioides (Orthoptera] provide the first experimental evidence that canavanine can disrupt the tertiary and/or quaternary structure that yields the three-dimensional conformation unique to the protein. These findings enhance our understanding of the biochemical basis for canavanine's antimetabolic and potent insecticidal properties. |