References of "Echterbille, Julien"
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See detailNew mass spectrometry based methodology to sequence a whole snake venom
Echterbille, Julien ULg; Boulanger, Madeleine; Degueldre, Michel ULg et al

Poster (2014, February 10)

Animal venoms are complex chemical cocktails, comprising wide ranges of biologically active reticulated peptides that target with high selectivity and efficacy varieties of membrane receptors. Assuming ... [more ▼]

Animal venoms are complex chemical cocktails, comprising wide ranges of biologically active reticulated peptides that target with high selectivity and efficacy varieties of membrane receptors. Assuming the fact that each of the 170,000 venomous species reported can produce more than 250 bioactive toxins, at least 40,000,000 bioactive peptides and proteins may be discovered. Among the four described species of mambas, Eastern Jameson’s mamba (Dendroaspis jamesonii kaimosae) venom is the less characterized since only 9 peptides are referenced in database. This work aims at developing a new strategy devoted to the deep analysis of animal venoms. Our approach consists in a first separation of the venom using cation exchange chromatography. Each primary fraction is then purified a second time by classical RP-HPLC. A total of 328 fractions, containing amongst 1 and 4 toxins, are finally collected. MALDI-MS analysis of each fraction is done in order (1) to obtain information about masses and (2) to obtain sequences of toxins thanks to MALDI-In Source Decay (ISD) dissociation coupled with on MALDI target plate reduction of the peptides. ISD has already been demonstrated efficient for toxin sequencing, and especially when using 1,5-DAN as reducing matrix. ISD yields to sequences that cover more than 50% of peptide sequences by series of singly charged c-type ions. Thanks to this methodology, we were able to obtain 85% of satisfactory results i.e. spectra giving quite long tags of amino acids (up to 20 residues). As a way to validate our method, a tag coming from ISD spectrum interpretation has found a match in database for an Eastern Jameson’s mamba toxin. The global sequence has then been obtained by extrapolation on the ISD spectrum. Since ISD spectra are simpler than classical MS/MS spectra, automation of spectra interpretation, difficult with other fragmentation techniques (CID, ETD…), is implementable. In the near future, sequences obtained with this approach will be used to direct tests of biological activity through sequence homologies with already known ligands for different kinds of membrane receptors. [less ▲]

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See detailAttribution of Cysteine Connectivities in small toxins - New Prospects Based on Partial Oxidation/Reduction Experiments and Ion-Mobility Mass Spectrometry
Quinton, Loïc ULg; Massonnet, Philippe ULg; Echterbille, Julien ULg et al

Conference (2013, December)

Disulfide bonds are post-translational modifications often found in biological compounds and especially in animal toxins. Disulfide bonds participate in the formation of specific folding of peptides and ... [more ▼]

Disulfide bonds are post-translational modifications often found in biological compounds and especially in animal toxins. Disulfide bonds participate in the formation of specific folding of peptides and proteins, directly related to their biological activity. Cystein pairing determinations are primordial for the synthesis of chemical homologous displaying the same bioactivity than the natural compound. This task appears already difficult when the cysteine pairings have to be determined from large proteins. The combination of physical and chemical techniques such as NMR, enzymatic proteolysis, liquid chromatography and mass spectrometry, is needed to circumvent this difficulty. However, when the work concerns small compounds such as conotoxins, the problem is much more complex due to the low amount of available compound and to the lack of enzymatic cleavage sites between cysteines. In this study, we investigate the case of small peptides that contain two disulphide bonds. The idea is to determine the cystein pairings in such compounds by a chemical partial reduction (or oxidation) of the peptides, followed by the separation of the generated species by ion-mobility mass spectrometry, and their characterisation by tandem mass spectrometry. Up to now, we have investigated the partial reduction not only in solution (with DTT and TCEP) but also in the gas-phase (Electron transfer dissociation), and partial oxidation in solution (with 3-CPBA). The results demonstrate an unexpected complexity of the data, including low fragmentation ratios of peptides and disulfide scramblings. [less ▲]

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See detailDe novo sequencing of unusual non tryptic peptides thanks to 4-sulfophenylisothiocyanate derivatization by post-source decay MALDI-MS.
Echterbille, Julien ULg; Quinton, Loïc ULg; Escoubas, Pierre et al

Poster (2013, June 11)

Introduction Due to the specificity of trypsin, tryptic peptides contain basic residues on the C-terminal side. This feature provides good ionization efficiency, and facilitates fragmentation processes ... [more ▼]

Introduction Due to the specificity of trypsin, tryptic peptides contain basic residues on the C-terminal side. This feature provides good ionization efficiency, and facilitates fragmentation processes. In the case of non tryptic peptides, the absence of basic residues at one extremity implicates lower fragmentation ratio and poor MS/MS spectra. Several methods have been developed to circumvent this drawback. Derivatization of peptides with compounds containing positive charge has been studied; Chen et al. (RCMS, 2004, 18, 191) demonstrated the simplification of CID spectra of tryptic peptides modified by 4-sulfophenylisothiocyanate. The result is a predominance of y-type ions. In this work, we evaluate the potential of SPITC for the de novo sequencing of unknown non-tryptic peptides containing disulfide bridges, i.e. peptide toxins from animal venoms. Methods 2µL of peptide solution (100 µM) were diluted in 6µL NH4HCO3 50mM (pH 8.7). As peptide toxins often contain disulfide bridges, reduction (2µL DTT 50mM, 1h at 56°C) and alkylation (2µL IAA 500mM, 1h in darkness at RT) of peptides were performed before the derivatization reaction. Peptides were then adsorbed on a C18 ZipTip micro-column followed by 10 µL of 4-sulfophenylisothiocyanate (SPITC) 50mM. The column was then incubated for 6h at 56°C. Peptides were washed by TFA 0.2% and eluted in 10µL 50/50 ACN/FA 0.1%, before being spotted in 2,5-DHB. MS experiments were performed using a Bruker Ultraflex II MALDI-TOF/TOF. FlexControl 3.0, FlexAnalysis 3.0, BioTools 3.2 and SequenceEditor 3.2 softwares (Bruker Daltonics, Bremen) were used for data acquisition and interpretation. Preliminary data According to our first results, SPITC derivatization allows in positive mode to direct the fragmentation thanks to the acidic character of the sulfonate moiety present on the modified molecule. Indeed, a large series of y-type ions is found in the CID spectra allowing determining easily large sequence tags. Moreover, the number of C-terminus ions (b- and a-type ions) decreases, which improve the simplification of MS/MS spectra. Due to this fragmentation pattern, SPITC derivatization is clearly valuable for the sequencing of peptides that are not described in databases (de novo sequencing). For example, animal venoms are composed of several hundreds of peptides that are poorly studied, up to now. These peptides display a high importance for pharmaceutical applications and their sequencing is, as a consequence, of prime interest. Peptide toxins, which are not resulting from an enzymatic digestion, are however difficult to sequence by classical MS/MS methods. In this work, we demonstrate that the modification of peptide toxins with SPITC reagent is suitable for “real” de novo sequencing. The method was applied to isolated peptides as well as chromatographic fractions that contain up to 30 toxins. The perspectives of this work rest on the study of the SPITC modified peptides in negative mode. We expect to obtain a better sensitivity due to the presence of the negative sulfonic acid group at the N-terminus extremity, and also interesting MS/MS spectra including mainly a- or b-type ions. The final challenge will be the application of the protocol to high throughput sequencing of peptide toxins from a large variety of animal venoms. Novel aspect De novo sequencing of unusual non-tryptic peptides thanks to 4-sulfophenylisothiocyanate derivatization by post-source decay MALDI-MS [less ▲]

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See detailLes venins d'animaux, nouvelle panacée?
Echterbille, Julien ULg; Quinton, Loïc ULg; De Pauw, Edwin ULg

in Athena (2013)

Araignées, serpents, scorpions,… autant d’animaux ayant une place particulière dans l’imaginaire collectif. Fascinants, horripilants voire même terrifiants, les adjectifs ne manquent pas pour qualifier ... [more ▼]

Araignées, serpents, scorpions,… autant d’animaux ayant une place particulière dans l’imaginaire collectif. Fascinants, horripilants voire même terrifiants, les adjectifs ne manquent pas pour qualifier les réactions qu’ils suscitent auprès des populations. Que dire alors de la peur engendrée par leur venin. Une simple piqûre, morsure ou contact peut s’avérer extrêmement dangereux voire létal... [less ▲]

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See detailIon-Mobility mass spectrometry as a potential tool to assign disulfide bonds arrangements in peptides with multiple disulfide bridges.
Echterbille, Julien ULg; Quinton, Loïc ULg; Gilles, Nicolas et al

in Analytical Chemistry (2013)

Disulfide bridges play a major role in defining the structural properties of peptides and proteins. However, the determination of the cysteine pairing is still challenging. Peptide sequences are usually ... [more ▼]

Disulfide bridges play a major role in defining the structural properties of peptides and proteins. However, the determination of the cysteine pairing is still challenging. Peptide sequences are usually achieved using MS/MS spectra of the totally reduced unfolded species but the cysteine pairing information is lost. On the other hand, MS/MS experiments performed on native folded species show complex spectra composed of non-classical ions. MS/MS alone does not allow the cysteine pairing nor the full sequence of an unknown peptide to be determined. The major goal of this work is to set up a strategy for the full structural characterization of peptides including disulfide bridges annotation in the sequence. This strategy was developed by combining Ion Mobility Spectrometry (IMS)and Collision Induced Dissociation(CID). It is assumed that the opening of one S-S bridges in a peptide leads to a structural evolution which results in a modification of IMS drift time. In the presence of multiple S-S bridges, the shift in arrival time will depend on which disulfide(s) has (have) been reduced and on the shape adopted by the generated species. Due to specific fragmentations observed for each species, CID experiments performed after the mobility separation could provide not only information on peptide sequence, but also on the localization of the disulfide bridges. To achieve this goal, synthetic peptides containing two disulfides were studied. The openings of the bridges were carried out following different experimental conditions such as reduction, reduction/alkylation or oxidation. Due to disulfide scrambling highlighted with the reduction approaches, oxidation of S-S bonds into cysteic acids appeared to be the best strategy. Cysteines connectivity was then unambiguously determined for the two peptides, without any disulfide scrambling interference. [less ▲]

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See detailDisulfide bond scrambling in partially reduced and alkylated peptides revealed by Ion Mobility Mass Spectrometry
Echterbille, Julien ULg; Quinton, Loïc ULg; De Pauw, Edwin ULg

Poster (2012, March 29)

Animal venoms are mainly composed of peptide toxins, which are highly structured by many disulfide bridges. In these toxins, disulfides play different major roles such as increasing the toxins efficiency ... [more ▼]

Animal venoms are mainly composed of peptide toxins, which are highly structured by many disulfide bridges. In these toxins, disulfides play different major roles such as increasing the toxins efficiency by lowering their immunogenicity or providing the adequate conformation to efficiently bind to the biological receptor. Peptide sequencing followed by determination of the cysteine pairings is still challenging and, therefore, an important step in structural analysis. This work was, in its beginning, focused on the development of ion mobility (IMS) based methodology used to assign disulfides. The strategy relies on the analysis of partially reduced/alkylated disulfide containing peptides. The resulting mixture is analyzed by ion mobility, followed by MS/MS acquisition on each mobility resolved species. Surprisingly, first investigations revealed, after partial reduction, a disulfide rearrangement phenomenon. Indeed, some of the cystein pairings were not those expected to be. These experiments were conducted on ¿-CnI and ¿-GI toxins purified from the venoms of Conus consors and Conus geographus marine snails, respectively. Each toxin contains four cysteines linked together with two disulfide bridges. Peptides were partially reduced by an excess of dithiothreitol and then alkylated by a large excess of iodoacetamide. The resulting mixture was purified on a microcolumn before being analyzed by nanoESI-Synapt-G2. Fragmentation was performed after the mobility cell, to obtain specific fragments of each species. Each toxin partially reduced/alkylated results, theoretically, in a mixture of fully oxidized (two disulfides oxidized), fully reduced (two disulfides reduced) and partially reduced forms (one of the two disulfides reduced). Thanks to the mass shift created by the alkylation, an isolation of the species which m/z ratio corresponds to one disulfide reduced and alkylated has been done in the quadrupole before the mobility separation. The arrival time distribution of triply charged ions reveals the presence of different species (4 in the case of ¿-GI and 2 for ¿-CnI), characterized by different relative cross sections in the gas-phase. As ion mobility resolved species give characteristic fragments upon fragmentation (after IMS), we were able to identify a scrambling of the disulfides (isomerization). In simple words, other disulfide bonds than expected ones were characterized. We suppose that the scrambling phenomenon occurs in solution,during the reduction step, since the alkylation cannot avoid rearrangement. The method is now being applied to more complex systems containing 3 or 4 disulfide bridges. The influence of the charge state on the mobility separation is systematically analyzed in terms of structural implications. [less ▲]

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See detailThe usefulness of Ion Mobility-Mass Spectrometry for Small Molecules Analysis
Far, Johann ULg; Goscinny, Séverine ULg; Joly, Laure et al

Conference (2012, March)

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See detailMass spectrometry as a tool to search specific ligands for G protein coupled receptors.
Cologna, Camila Takeno; Echterbille, Julien ULg; De Pauw, Edwin ULg et al

Conference (2012)

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See detailDisulfide bond assignement and folding characterization of peptide toxins by Ion Mobility Mass Spectrometry
Echterbille, Julien ULg; Quinton, Loïc ULg; Rosu, Frédéric ULg et al

Conference (2011, October 11)

Main component of animal venoms is peptide toxins, which are highly structured by several disulfide bridges. Disulfide bridges fill different roles as increasing the toxins efficiency by lowering their ... [more ▼]

Main component of animal venoms is peptide toxins, which are highly structured by several disulfide bridges. Disulfide bridges fill different roles as increasing the toxins efficiency by lowering their immunogenicity or providing the adequate conformation to efficiently bind to the biological receptor. The sequencing and the determination of the cysteine pairing is still challenging and therefore an important step in structural analysis. In this work, we present a new strategy to sequence structured toxins and assign S-S bridges using ion mobility resolved MS/MS. The method relies on the analysis of partially reduced multiple-disulfide peptide. The mixture of the different forms is resolved by ion mobility, followed by MS/MS acquisition on each mobility separated species. The proof of concept has been successfully conducted on α-CnI, a toxin purified from the venom of Conus consors marine snail. The toxin’s sequence contains four cysteines linked together with two disulfide bridges. α-CnI was partially reduced by a small excess of tris(carboxyethyl)phosphine (10:1). The resulting mixture was purified before analysis by infusion nanoESI-Synapt-G2. Fragmentation was performed after the mobility cell, to obtain specific fragments of each species. Partial reduction of α-CnI results in a mixture of oxidized (the two disulfides are formed), reduced (the two disulfides have been reduced) and partially reduced forms (one of the two disulfides has been reduced). The arrival time distribution of triply charged ions reveals the presence of 4 different species, characterized by different relative cross sections in the gas-phase. Mass matching allows identifying the species: the first mobility (the most compact structure) was identified to be the oxidized folded toxin (M). The latest peak, corresponding to the larger cross-section, was identified as the fully reduced toxin (M+4Da). The second and the third mobility peaks were attributed to the two partially reduced forms in which only one disulfide bridge was reduced (M+2Da). The change in ion mobility depends on which S-S bridge is reduced. Ion mobility separated species give characteristic fragment ions upon fragmentation in the transfer cell (i.e. after ion mobility separator). Interestingly, fragment ions coming from partially reduced species, especially the C-S or S-S bond cleavages, clearly indicates that the disulfide linkage of α-CnI is (Cys1-Cys3) and (Cys2-Cys4) as expected from literature. The method is now being applied with success to more complex systems containing 3 or 4 disulfide bridges. The influence of the charge state on the mobility separation is systematically analyzed in terms of structural implications. [less ▲]

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See detailMass spectrometry as an evolutive tool for toxinology: from sequencing to toxin shapes
Quinton, Loïc ULg; Gilles, Nicolas; Echterbille, Julien ULg et al

Conference (2011, September 12)

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See detailDisulfide bonds assignment and folding characterization of peptide toxins by Ion Mobility Mass Spectrometry
Echterbille, Julien ULg; Quinton, Loïc ULg; De Pauw, Edwin ULg et al

Conference (2011, April 29)

Main component of animal venoms is peptide toxins, which are highly structured by several disulfide bridges. Disulfide bridges fill different roles as increasing the toxins efficiency by lowering their ... [more ▼]

Main component of animal venoms is peptide toxins, which are highly structured by several disulfide bridges. Disulfide bridges fill different roles as increasing the toxins efficiency by lowering their immunogenicity or providing the adequate conformation to efficiently bind to the biological receptor. The sequencing and the determination of the cysteine pairing is still challenging and therefore an important step in structural analysis. In this work, we present a new strategy to sequence structured toxins and assign S-S bridges using ion mobility resolved MS/MS. The method relies on the analysis of partially reduced multiple-disulfide peptide. The mixture of the different forms is resolved by ion mobility, followed by MS/MS acquisition on each mobility separated species. The proof of concept has been successfully conducted on α-CnI, a toxin purified from the venom of Conus consors marine snail. The toxin’s sequence contains four cysteines linked together with two disulfide bridges. α-CnI was partially reduced by a small excess of tris(carboxyethyl)phosphine (10:1). The resulting mixture was purified before analysis by infusion nanoESI-Synapt-G2. Fragmentation was performed after the mobility cell, to obtain specific fragments of each species. Partial reduction of α-CnI results in a mixture of oxidized (the two disulfides are formed), reduced (the two disulfides have been reduced) and partially reduced forms (one of the two disulfides has been reduced). The arrival time distribution of triply charged ions reveals the presence of 4 different species, characterized by different relative cross sections in the gas-phase. Mass matching allows identifying the species: the first mobility (the most compact structure) was identified to be the oxidized folded toxin (M). The latest peak, corresponding to the larger cross-section, was identified as the fully reduced toxin (M+4Da). The second and the third mobility peaks were attributed to the two partially reduced forms in which only one disulfide bridge was reduced (M+2Da). The change in ion mobility depends on which S-S bridge is reduced. Ion mobility separated species give characteristic fragment ions upon fragmentation in the transfer cell (i.e. after ion mobility separator). Interestingly, fragment ions coming from partially reduced species, especially the C-S or S-S bond cleavages, clearly indicates that the disulfide linkage of α-CnI is (Cys1-Cys3) and (Cys2-Cys4) as expected from literature. The method is now being applied with success to more complex systems containing 3 or 4 disulfide bridges. The influence of the charge state on the mobility separation is systematically analyzed in terms of structural implications. [less ▲]

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See detailNew Methodology to detect toxin-GPCR binding by MALDI-TOF Mass Spectrometry
Echterbille, Julien ULg; De Pauw, Edwin ULg; Gilles, Nicolas et al

Poster (2011)

Introduction More than 50 thousands of venomous species are currently indexed in the world. Each of their venoms is composed of 200 to 1000 different toxins which potentially exhibit a high selectivity ... [more ▼]

Introduction More than 50 thousands of venomous species are currently indexed in the world. Each of their venoms is composed of 200 to 1000 different toxins which potentially exhibit a high selectivity for membrane receptors such as ionic channels or G-protein coupled receptors (GPCRs). GPCRs constitute the larger family of receptors since around 800 different kinds of them are knows. GPCRs are the target of around 30% of the current pharmacopeia drugs. Notable examples include Novartis’s Zelnorm, Eli Lilly’s Zyprexa and Schering-Plough’s Clarinex used to treat constipation, schizophrenia and allergies, respectively. Finding new GPCRs ligands appears of prime interest to design new pharmacological tools and potentially discover the drugs of our future. Interestingly, several toxins from venoms have already been described to bind to this particular family of receptor, opening the way to the discovery of new peptide drugs from animal venoms1-2. This work presents a pioneering MALDI-TOF/TOF based strategy to fish new GPCRs ligands from complex mixtures such as venom fractions. Methods The proof of concept of this methodology was built by studying the binding of [Arg8]-vasopressin (AVP) on type 2-vasopressin receptor (V2). Experimentally, fragments of cellular membranes over-expressing V2 receptors were incubated with cone snail’s venom fraction (~30 peptide toxins) doped by a small amount of AVP. After 2 hours incubation, free and bound fractions were carefully purified with a combination of centrifugation and micro column purifications. Samples were finally analyzed with a Bruker Ultraflex II MALDI-TOF/TOF mass spectrometer and the resulting spectra were interpreted with FlexAnalysis (v3.0), BioTools (v3.2) and SequenceEditor (v3.2) bioinformatics’ softwares from Bruker Daltonics. Preliminary data After the incubation of cellular membranes overexpressing V2 GPCR with a complex mixture of peptides doped by AVP, we clearly detect that the only V2 ligand present in the fraction was the AVP. Our result demonstrates the possibility to identify a ligand of GPCRs from a complex peptide mixture, such as venom fractions. Contrary to radiobinding, this approach allows detecting the direct binding of the toxin and does not imply to know a ligand of the studied GPCR before starting the experiments. This opens the way to the deorphanization of receptors (180 orphans GPCRs over 800). Moreover, since the new ligand is detected by mass spectrometry, it is directly identified from the mixture, without additional purification. Its structural characterization can be directly performed by de novo sequencing experiments. The drawback of our approach is the very long (but crucial!) sample preparation as each sample requires 2 purification steps (for both free and bound fraction). The next step of our work will be the automation of the procedure to allow a high-throughput screening of venom fractions on different GPCRs and the discovery of new ligands. Novel aspect GPCR’s ligands discovery by MALDI-TOF/TOF based techniques: a new pharmacological tool. 1 Quinton, L. et al. Isolation and pharmacological characterization of AdTx1, a natural peptide displaying specific insurmountable antagonism of the a1A-adrenoceptor. British Journal of Pharmacology 159, 316-325 (2010). 2 Rouget, C. et al. Identification of a novel snake peptide toxin displaying high affinity and antagonist behaviour for the α2-adrenoceptors. British Journal of Pharmacology 161, 1361-1374, doi:10.1111/j.1476-5381.2010.00966.x (2010). [less ▲]

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See detailDisulfide bond assignment and folding characterization of peptide toxins by Ion Mobility Mass Spectrometry
Echterbille, Julien ULg; Quinton, Loïc ULg; Rosu, Frédéric ULg et al

Poster (2011)

Introduction Animal venoms are mainly composed of peptide toxins, which are highly structured by several disulfide bridges. Disulfide bridges are a key feature as (i) they increase the toxins efficiency ... [more ▼]

Introduction Animal venoms are mainly composed of peptide toxins, which are highly structured by several disulfide bridges. Disulfide bridges are a key feature as (i) they increase the toxins efficiency by lowering their immunogenicity; (ii) they provide the adequate conformation for high affinity binding to the biological receptor. The sequencing and the determination of the cysteine pairing is still challenging and therefore an important step in their structure analysis and the understanding of their interactions with receptors. In this work, we present a new strategy to sequence structured toxins and assign S-S bridges using ion mobility resolved MS/MS. Methods The method relies on the analysis of partially reduced multiple-disulfide peptide. The mixture of the different forms is resolved by ion mobility, followed by MS/MS acquisition on each mobility separated species. The proof of concept has been successfully conducted on α-CnI, a toxin purified from the venom of Conus consors marine snail. The toxin sequence is GRCCHPACGKYYSC-NH2. It contains four cysteines linked together with two disulfide bridges. α-CnI was partially reduced by a small excess of tris(carboxyethyl)phosphine (10:1) at 56°C during 30min. The resulting mixture was purified by ZipTip C18 micro columns before analysis by infusion nanoESI-Synapt-G2. Fragmentation was performed after the mobility cell, to obtain specific fragments of each species. Mobilograms and mass spectra were analyzed using MassLynx (v4.1) and Driftscope (v2.1) from Waters. Preliminary data Partial reduction of a-CnI was performed in order to obtain a mixture of oxidized (the two disulfides are formed), reduced (the two disulfides have been reduced) and partially reduced forms (only one of the two disulfides has been reduced). The arrival time distribution of triply charged ions reveals the presence of 4 different species, characterized by a different relative cross sections in the gas-phase. The charge state of the ions influences the ion mobility separation. Mass matching allows identifying the species: the first mobility (the most compact structure) was identified to be the oxidized folded toxin (M=1541.58 Da). The latest peak, corresponding to the larger cross-section, was identified as the fully reduced toxin (M=1545.6 Da). The second and the third mobility peaks were attributed to the two partially reduced forms in which only one disulfide bridge was reduced (M=1543.59 Da). The change in ion mobility depends on which S-S bridge is reduced. Ion mobility separated species give characteristic fragment ions upon fragmentation in the transfer cell (i.e. after ion mobility separator). Interestingly, fragment ions coming from partially reduced species, especially the C-S or S-S bond cleavages, clearly indicates that the disulfide linkage of α-CnI is (Cys1-Cys3) and (Cys2-Cys4) as expected from literature. The method is now being applied with success to more complex systems containing 3 or 4 disulfide bridges. The influence of the charge state on the mobility separation is systematically analyzed in terms of structural implications. Novel aspect Sequencing and disulfide bridges assignment of peptide toxins using ion mobility resolved MS/MS [less ▲]

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See detailMass spectrometric sequencing of peptidic toxins : an overview
Quinton, Loïc ULg; Echterbille, Julien ULg; Pierre, Escoubas et al

in Editions de la SFET – SFET Editions (2010)

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See detailMALDI-TOF/TOF sequencing of peptide toxins from animal venoms
Quinton, Loïc ULg; Echterbille, Julien ULg; Gilles, Nicolas et al

Poster (2010, April 16)

Detailed reference viewed: 33 (9 ULg)