Publications

2005

• Imagerie non linéaire et microdissection par impulsions ultrabrèves pour l'étude du développement embryonnaire
  
  • Supatto Willy
  • Débarre Delphine
  • Moulia Bruno B.
  • Martin Jean-Louis
  • Schanne-Klein Marie-Claire
  • Farge Emmanuel
  • Beaurepaire Emmanuel
  , 2005.
• La ciguatera : de l'étiologie du phénomène au traitement de ses symptômes. [Ciguatera: from the etiology of the phenomenon to the treatment of its symptoms]
  
  • Boydron-Le Garrec Raphaële
  • Benoit Evelyne
  • Sauviat Martin-Pierre
  • Frostin Maryvonne
  • Laurent Dominique
  Journal de la Société de Biologie, 2005, 199(2), pp.127-139. Ciguatera is the most common food poisoning found in the tropical and subtropical areas, acquired by the consumption of marine products. A lot of work concerning its etiology, its epidemiology and its clinical effects, as well as the discovery of the toxins involved, the description of their transfer, the study of their structure and the analysis of their pharmacological effects, have allowed a better understanding of the ciguateric phenomenon. Ciguatera is known to be due to benthic dinoflagellates belonging to the Gambierdiscus gender, in particular G. toxicus. Under specific conditions, this microalga produces gambier-toxins, toxins which are the precursors of other toxins, the ciguatoxins. However, the factors supporting this production are still poorly known, and the implication of others dinoflagellates, cyanophytes or bacteria have been suspected. In contrast, the fish species responsible for the transmission of ciguatera are globally well identified. The clinical symptoms of the intoxication are now well described. They mainly include digestive, neurological and cardiovascular disorders whose preponderance varies according to the nature of the toxins involved, since toxin structures are different between one ocean and the other. The ciguateric intoxication tends to be exported towards non endemic areas where it is still misdiagnosed. No specific antidote exists to date, and it is only by symptomatic or palliative treatments that ciguatera is currently treated.
• Détection des ciguatoxines: avantages et inconvénients des différentes méthodes biologiques utilisées [Detection of ciguatoxins: advantages and drawbacks of different biological methods]
  
  • Boydron-Le Garrec Raphaële
  • Benoit Evelyne
  • Sauviat Martin-Pierre
  • Laurent Dominique
  Journal de la Société de Biologie, 2005, 199 (2), pp.115-125. La ciguatera est une intoxication consécutive à la consommation de poissons des récifs contaminés par des toxines spécifiques, les ciguatoxines, à des niveaux capables d'engendrer chez l'Homme une toxicité par voie orale. Les précurseurs de ces toxines sont les gambiertoxines, produites par des Dinoflagellés du genre Gambierdiscus. Ces toxines sont accumulées dans le foie et la chair des poissons brouteurs, herbivores et carnivores, et biotransformées en ciguatoxines plus nocives pour l'Homme. En l'absence de traitement spécifique, la ciguatera reste un problème non seulement de santé publique, mais également socio-économique. La détection des ciguatoxines, au sein des poissons ou de leurs extraits, est donc primordiale et recherchée depuis longtemps. De nombreuses méthodes, biologiques, chimiques ou immunochimiques, ont été développées dans ce but. Cette revue est plus particulièrement centrée sur les méthodes biologiques, développées in vivo ou in vitro, depuis le test de toxicité aiguë sur Souris, maintenant parfaitement standardisé, jusqu'aux méthodes les plus récentes telles que le test de fixation spécifique sur synaptosomes de Rat. Outre la Souris, le Poulet et la Mangouste ont été encore récemment utilisés, notamment pour des tests préliminaires avant l'extraction des ciguatoxines à partir des poissons. Au contraire, diverses autres méthodes in vivo, telles que celles pratiquées sur le Chat, les Culicidés ou les larves de Diptères, furent abandonnées malgré leurs résultats intéressants. Finalement, bien qu'excluant une détection des ciguatoxines sur le terrain, les tests sur neuroblastomes de Souris et synaptosomes de Rat, nouvelles méthodes réalisées in vitro, ont permis un gain considérable tant en sensibilité qu'en spécificité pour détecter les ciguatoxines.
• Implication de la nociception cutanée dans l'intoxination de type ciguatera.
  
  • Benoit Evelyne
  • Boydron-Le Garrec Raphaële
  • Sauviat Martin-Pierre
  , 2005, pp.123-130.
• Ability of some plant extracts , traditionally used to treat ciguatera fish poisoning, to prevent the in vitro neurotoxicity produced by sodium channel activators.
  
  • Boydron-Le Garrec Raphaële
  • Benoit Evelyne
  • Sauviat Martin-Pierre
  • J. Lewis Richard
  • Molgó Jordi
  • Laurent Dominique
  Toxicon, Elsevier, 2005, 46(6), pp.625-634. The effects of 31 plant extracts, which most are traditionally used to treat ciguatera fish poisoning in the Pacific area, were studied on the cytotoxicity of mouse neuroblastoma cells produced by ouabain, veratridine and/or brevetoxin-3 or Pacific ciguatoxin-1. The cell viability was determined using a quantitative colorimetric method. A marked cytotoxicity of seven of the 31 plant extracts studied, was observed. Despite this, these plant extracts were suspected to contain active compound(s) against the cytotoxicity produced by brevetoxin (2 extracts), brevetoxin, ouabain and/or veratridine (3 extracts), or only against that of ouabain and/or veratridine (2 extracts). Among the 24 plant extracts that exhibited by themselves no cytotoxicity, 22 were active against the effect of brevetoxin or against that of both veratridine and brevetoxin. Similar results were obtained when the seven most active plant extracts were reassayed using ciguatoxin instead of brevetoxin. In conclusion, the present work reports the first activity assessment of some plant extracts, achieved in vitro on a quite large scale. The fact that 27 plant extracts were found to exert, in vitro, a protective effect against the action of ciguatoxin and/or brevetoxin, paves the way for finding new active compounds to treat ciguatera fish poisoning, provided these compounds also reverse the effects of sodium channel activators. (10.1016/j.toxicon.2005.07.002)
  DOI : 10.1016/j.toxicon.2005.07.002
• Observation of sub-100 ps conformational changes in photolyzed carbonmonoxy-myoglobin probed by time-resolved circular dichroism
  
  • Dartigalongue Thibault
  • Hache François
  Chemical Physics Letters, Elsevier, 2005, 415 (4-6), pp.313-316. A time-resolved circular dichroism (CD) experiment is carried out on carbonmonoxy-myoglobin. The CD is measured with a sub-picosecond time resolution after ligand dissociation and the data are interpreted thanks to a classical CD calculation based on the polarizability theory. We observe a decrease of the CD signal in a few picoseconds and a sub-100 ps relaxation towards steady-state deoxy-myoglobin values which we assign to a stress of the proximal histidine which relaxes with the global reorganization of the protein from its liganded geometry to its deliganded one. 2005 Elsevier B.V. All rights reserved (10.1016/j.cplett.2005.09.022)
  DOI : 10.1016/j.cplett.2005.09.022
• Sudden polarisation and coherent vibration in bacteriorhodopsin
  
  • Groma Geza
  • Colonna Anne
  • Joffre Manuel
  • Vos Marten H.
  • Martin Jean-Louis
  , 2005.
• Etudes spectroscopiques du senseur à oxygène FixL
  
  • Jasaitis Audrius
  • Vos Marten H.
  • Balland Véronique
  • Mattioli T. A.
  • Bouzhir-Sima Latifa
  • Liebl Ursula
  , 2005, pp.poster.
• Spectroscopic analysis of keratin endogenous signal for skin multiphoton microscopy: erratum
  
  • Pena Ana-Maria
  • Strupler Mathias
  • Boulesteix Thierry
  • Godeau G.
  • Schanne-Klein Marie-Claire
  Optics Express, Optical Society of America - OSA Publishing, 2005, 13 (17), pp.6667. We present corrected versions of the list of authors and of Section 2.1. (10.1364/OPEX.13.006667)
  DOI : 10.1364/OPEX.13.006667
• Mid-infrared electric field characterization using a visible charge-coupled-device-based spectrometer
  
  • Kubarych Kevin J.
  • Joffre Manuel
  • Moore Amy
  • Belabas Nadia
  • Jonas David
  Optics Letters, Optical Society of America - OSA Publishing, 2005, 30 (10), pp.1228-1230. We characterize ultrashort mid-infrared pulses through upconversion by using the stretched pulses obtained from the uncompressed output of a chirped-pulse amplifier. The power spectrum thus translated into the visible region can be readily measured with a standard silicon CCD camera-based spectrometer. The spectral phase is also characterized by a variant of zero-added-phase spectral phase interferometry for direct electric field reconstruction. This is a general method that provides a multiplex advantage over conventional infrared detector array-based methods. © 2005 Optical Society of America (10.1364/OL.30.001228)
  DOI : 10.1364/OL.30.001228
• Functionality of nitrated acetylcholine receptor: The two-step formation of nitrotyrosines reveals their differential role in effectors binding
  
  • Négrerie Michel
  • Martin Jean-Louis
  • Nghiêm H.-O.
  FEBS Letters, Wiley, 2005, 579 (12), pp.2643. The presence of nitrotyrosines is associated with several neurodegenerative pathologies. We evaluated the functionality of the nicotinic acetylcholine receptor possessing nitrotyrosines. The spectrum of the nitrated receptor displays an absorption band characteristic of ortho-nitrophenol. The presence of carbamylcholine in the agonist site prevented the effect of nitration by tetranitromethane in some conditions. The nitration occurred with two discrete steps and pointed out the differential involvement of tyrosines in the binding of acetylcholine and neurotoxin. We concluded that at least two residues involved in agonist binding can be nitrated, which bring similar contributions to the binding energy of the neurotransmitter. Cop. 2005 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved. (10.1016/j.febslet.2005.03.084)
  DOI : 10.1016/j.febslet.2005.03.084
• Activationless electron transfer through the hydrophobic core of cytochrome c oxidase
  
  • Jasaitis Audrius
  • Rappaport F.
  • Pilet Eric
  • Liebl Ursula
  • Vos Marten H.
  Proceedings of the National Academy of Sciences of the United States of America, National Academy of Sciences, 2005, 102 (31), pp.10882. Electron transfer (ET) within proteins occurs by means of chains of redox intermediates that favor directional and efficient electron delivery to an acceptor. Individual ET steps are energetically characterized by the electronic coupling V, driving force ΔG, and reorganization energy λ. λ reflects the nuclear rearrangement of the redox partners and their environment associated with the reactions; λ ≈ 700-1,100 meV (1 eV = 1.602 × 10-19 J) has been considered as a typical value for intraprotein ET. In nonphotosynthetic systems, functional ET is difficult to assess directly. However, using femtosecond flash photolysis of the CO-poised membrane protein cytochrome c oxidase, the intrinsic rate constant of the low-ΔG electron injection from heme a into the heme a 3-CuB active site was recently established at (1.4 ns)-1. Here, we determine the temperature dependence of both the rate constant and ΔG of this reaction and establish that this reaction is activationless. Using a quantum mechanical form of nonadiabatic ET theory and common assumptions for the coupled vibrational modes, we deduce that λ is <200 meV. It is demonstrated that the previously accepted value of 760 meV actually originates from the temperature dependence of CuB-CO bond breaking. We discuss that low-ΔG, low-λ reactions are common for efficiently channeling electrons through chains that are buried inside membrane proteins. (10.1073/pnas.0503001102)
  DOI : 10.1073/pnas.0503001102
• Third harmonic generation microscopy for the velocimetric analysis of Drosophila embryo development
  
  • Débarre Delphine
  • Supatto Willy
  • Farge Emmanuel
  • Moulia Bruno B.
  • Schanne-Klein Marie-Claire
  • Beaurepaire Emmanuel
  , 2005.
• Multiphoton microscopy of unstained living cardiac and vascular tissue
  
  • Pena Ana-Maria
  • Boulesteix Thierry
  • Pagès Nicole
  • Senni Karim
  • Godeau Gaston
  • Sauviat Martin-Pierre
  • Beaurepaire Emmanuel
  • Schanne-Klein Marie-Claire
  , 2005.
• Spectroscopic analysis of keratin endogenous signal for skin multiphoton microscopy
  
  • Pena Ana-Maria
  • Strupler Mathias
  • Boulesteix Thierry
  • Schanne-Klein Marie-Claire
  Optics Express, Optical Society of America - OSA Publishing, 2005, 13 (16), pp.6268-6274. We recorded one-photon excited fluorescence (1PEF) and two-photon excited fluorescence (2PEF) spectra of purified keratin from human epidermis, and determined the action cross section of this endogenous chromophore. We used this spectroscopic analysis to analyse multiphoton images of skin biopsies and assign the intrinsic fluorescence signals in the epidermis. We observed a good agreement between in situ and in vitro 2PEF spectra of keratin. This study provides a comprehensive characterization of the 2PEF signal of the keratins from the epidermis, and will be of practical interest for multiphoton imaging of the skin. © 2005 Optical Society of America (10.1364/OPEX.13.006268)
  DOI : 10.1364/OPEX.13.006268
• Nonlinear spectroscopy of chiral molecules
  
  • Fischer P.
  • Hache François
  Chirality, Wiley, 2005, 17, pp.421-437.
• Etudes fonctionnelles du senseur à oxygène bactérien Dos
  
  • Bouzhir-Sima Latifa
  • Jasaitis Audrius
  • Vos Marten H.
  • Liebl Ursula
  , 2005.
• Functionalized luminescent oxide nanoparticles for single Na+ channel imaging
  
  • Casanova Didier
  • Giaume D.
  • Beaurepaire Emmanuel
  • Sauviat Martin-Pierre
  • Auksorius Egidijus
  • Buissette V.
  • Lahlil K.
  • Martin Jean-Louis
  • Gacoin Thierry
  • Boilot Jean-Pierre
  • Alexandrou Antigoni
  , 2005.
• 11th Congress of the European Society for Photobiology
  
  • Dartigalongue Thibault
  • Hache François
  , 2005.
• Dynamique ultrarapide au sein des protéines vue par spectroscopie optique: interactions hémoprotéines-ligands
  
  • Vos Marten H.
  , 2005.
• Geminate carbon monoxide rebinding to a c-type haem
  
  • Silkstone G.
  • Jasaitis Audrius
  • Vos Marten H.
  • Wilson M.
  Dalton Transactions, Royal Society of Chemistry, 2005, 21 (7), pp.3489. A chemically modified form of cytochrome c (cyt. c), termed carboxymethyl cytochrome c (cm cyt. c), possesses a vacant sixth coordination site to the haem iron that is available to bind external ligands. We present data on the rapid flash photolysis of CO from the ferrous haem iron of cm cyt. c and describe the kinetics and spectral transitions that accompany the recombination. This was achieved using 30-femtosecond laser pulses and a white light continuum to monitor spectral transitions. Whereas the photo-dissociation quantum yield is close to 1, the yield of CO escape from the protein (the apparent quantum yield, φ) relative to myoglobin (φ = 1) is small due to rapid geminate recombination of CO. On ligand photo-dissociation the haem undergoes a spin-state transition from low-spin ferrous CO bound to penta-coordinate high-spin. Subsequently the system reverts to the CO bound form. The data were fitted with a minimum number of exponentials using global analysis. Recombination of CO with the haem iron of cm cyt. c is multiphasic (τ = 16 ps, 120 ps and 1 ns), involving three spectrally distinct components. The fraction of haem (0.11) not recombining with CO within 4 ns is similar to the value of φ (0.12) measured on the same preparation by the "pulse method" (M. Brunori, G. Giacometti, E. Antonini and J. Wyman, Proc. Natl. Acad. Sci. USA, 1973, 70, 3141-3144, ). This implies that no further geminate recombination occurs at t > 4 ns. This unusually efficient CO-haem geminate recombination indicates the sterically hindered ("caged") nature of the distal haem pocket in cm cyt. c from which it is difficult for CO to escape. The large geminate phase may be contrasted with the behaviour of myoglobin in which geminate recombination is small. This is in general agreement with the well-documented extensive structural dynamics in myoglobin that allow ligand passage, and a higher structural rigidity in cyt. c imposed by the restraints of minimising reorganisation energy for electron transfer (M. Brunori, D. Bourgeois and D. Vallone, J. Struct. Biol., 2004, 147, 223-234, ). The high pH ferrous form of cm cyt. c is a low-spin species having a lysine bound to the central iron atom of the haem (M. Brunori, M. Wilson and E. Antonini, J. Biol. Chem., 1972, 247, 6076-6081; G. Silkstone, G. Stanway, P. Brzezinski and M. Wilson, Biophys. Chem., 2002, 98, 65-77, ). This high pH (pH 8) form of deoxy cm cyt. c undergoes photo-dissociation of lysine (although the proximal histidine is possible) after photo-excitation. Recombination occurs with a time constant (τ) of 7 ps. This is similar to that observed for the geminate rebinding of the Met80 residue in native ferrous cyt. c (τ 6 ps) following its photo-dissociation (S. Cianetti, M. Negrerie, M. Vos, J.-L. Martin and S. Kruglik, J. Am. Chem. Soc., 2004, 126, 13932-13933; W. Wang, X. Ye, A. Demidov, F. Rosca, T. Sjodin, W. Cao, M. Sheeran and P. Champion, J. Phys. Chem., 2000, 104, 10789-10801, ). (10.1039/B508183C)
  DOI : 10.1039/B508183C
• Calculation of the circular dichroism spectra of carbon monoxy- and deoxy myoglobin: interpretation of a time-resolved circular dichroism experiment.
  
  • Dartigalongue Thibault
  • Hache François
  The Journal of Chemical Physics, American Institute of Physics, 2005, 123 (18), pp.184901. A calculation of the circular dichroism (CD) spectra of carbon monoxy- and deoxy myoglobin is carried out in relation with a time-resolved CD experiment. The calculation is based on the polarizability theory and the parameters are adjusted to fit the experimental absorption and CD spectra. By performing the calculation for intermediate configurations of the protein, we are able to propose an explanation of the CD structure observed on a sub-100 ps time scale. The role of the proximal histidine is, in particular, clearly demonstrated in the first step of the myoglobin relaxation from its liganded to it deliganded form. (10.1063/1.2041467)
  DOI : 10.1063/1.2041467
• Retinal isomerization dynamics in dry bacteriorhodopsin films
  
  • Colonna Anne
  • Groma Geza I.
  • Vos Marten H.
  Chemical Physics Letters, Elsevier, 2005, 415 (1-3), pp.69-73. The primary photoprocesses in neutral and acid forms of oriented dried bacteriorhodopsin films were investigated by femtosecond absorption spectroscopy. The excitation energy dependence of the signals was used to distinguish photochemistry from processes involving photophysics of photocycle intermediates. Both the kinetics and the quantum yield of all-trans excited state decay by retinal photoisomerization and subsequent J → K transition were found to be very similar as in hydrated environments. Therefore, unlike slower photocycle phases, communication of the retinal with the environment does not play a role in retinal isomerization. Our results are important for understanding recent nonlinear optical applications of such films. (10.1016/j.cplett.2005.08.132)
  DOI : 10.1016/j.cplett.2005.08.132
• Fourier transform measurement of two-photon excitation spectra: applications to microscopy and optimal control
  
  • Ogilvie Jennifer P.
  • Kubarych Kevin J.
  • Alexandrou Antigoni
  • Joffre Manuel
  Optics Letters, Optical Society of America - OSA Publishing, 2005, 30, pp.911. We report a novel Fourier transform method for measuring two-photon excitation spectra. We demonstrate this method using simple dye molecules and discuss its applications in two-photon fluorescence microscopy and optimal control. This method facilitates an intuitive interpretation of recent control experiments in terms of tuning the nonlinear spectrum of the exciting laser source.
• Unstained Drosophila embryo development analysed by velocimetric third harmonic generation microscopy
  
  • Débarre Delphine
  • Supatto Willy
  • Farge Emmanuel
  • Moulia Bruno B.
  • Schanne-Klein Marie-Claire
  • Beaurepaire Emmanuel
  , 2005.