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John H. Bowie - One of the best experts on this subject based on the ideXlab platform.
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fragmentations of m h anions of peptides containing tyrosine Sulfate does the Sulfate Group rearrange a joint experimental and theoretical study
Rapid Communications in Mass Spectrometry, 2013Co-Authors: T Nha T Tran, Tianfang Wang, Sandra Hack, John H. BowieAbstract:RATIONALE To investigate the fragmentations in the negative-ion electrospray mass spectra of peptides containing tyrosine Sulfate. METHODS Possible fragmentation mechanisms were explored using a Waters QTOF2 tandem mass spectrometer in concert with calculations at the CAM-B3LYP/6-311++g(d,p) level of theory. RESULTS The major negative ion formed in the ESI-MS of peptides containing tyrosine Sulfate is [(M − H) − SO3]− and this process normally yields the base peak of the spectrum. The basic backbone cleavages of [(M − H) − SO3]− allowed the sequence of the peptide to be determined. Rearrangement reactions involving the formation of HOSO3− and [(M − H)−H2SO4]− yielded minor peaks with relative abundances ≤ 10% and ≤ 2%, respectively. CONCLUSIONS The mass spectra of the [M − H]− and [(M − H)−SO3]− anions of peptides containing tyrosine Sulfate allowed the position of the tyrosine Sulfate Group to be determined, together with the amino acid sequence of the peptide. Copyright © 2013 John Wiley & Sons, Ltd.
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Fragmentations of [M − H]− anions of peptides containing tyrosine Sulfate. Does the Sulfate Group rearrange? A joint experimental and theoretical study
Rapid communications in mass spectrometry : RCM, 2013Co-Authors: T. T. Nha Tran, Tianfang Wang, Sandra Hack, John H. BowieAbstract:RATIONALE To investigate the fragmentations in the negative-ion electrospray mass spectra of peptides containing tyrosine Sulfate. METHODS Possible fragmentation mechanisms were explored using a Waters QTOF2 tandem mass spectrometer in concert with calculations at the CAM-B3LYP/6-311++g(d,p) level of theory. RESULTS The major negative ion formed in the ESI-MS of peptides containing tyrosine Sulfate is [(M − H) − SO3]− and this process normally yields the base peak of the spectrum. The basic backbone cleavages of [(M − H) − SO3]− allowed the sequence of the peptide to be determined. Rearrangement reactions involving the formation of HOSO3− and [(M − H)−H2SO4]− yielded minor peaks with relative abundances ≤ 10% and ≤ 2%, respectively. CONCLUSIONS The mass spectra of the [M − H]− and [(M − H)−SO3]− anions of peptides containing tyrosine Sulfate allowed the position of the tyrosine Sulfate Group to be determined, together with the amino acid sequence of the peptide. Copyright © 2013 John Wiley & Sons, Ltd.
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an immunomodulator used to protect young in the pouch of the tammar wallaby macropus eugenii
FEBS Journal, 2005Co-Authors: Russell V Baudinette, Pinmanee Boontheung, Ian F Musgrave, Paul A Wabnitz, Vita M Maselli, Jayne Skinner, Paul F Alewood, Craig S Brinkworth, John H. BowieAbstract:Eugenin [pGluGlnAspTyr(SO3)ValPheMetHisProPhe-NH2] has been isolated from the pouches of female Tammar wallabies (Macropus eugenii) carrying young in the early lactation period. The sequence of eugenin has been determined using a combination of positive and negative ion electrospray mass spectrometry. This compound bears some structural resemblance to the mammalian neuropeptide cholecystokinin 8 [AspTyr(SO3)MetGlyTrpMetAspPhe-NH2] and to the amphibian caerulein peptides [caerulein: pGluGlnAspTyr(SO3)ThrGlyTrpMetAspPhe-NH2]. Eugenin has been synthesized by a route which causes only minor hydrolysis of the Sulfate Group when the peptide is removed from the resin support. Biological activity tests with eugenin indicate that it contracts smooth muscle at a concentration of 10(-9) m, and enhances the proliferation of splenocytes at 10(-7) M, probably via activation of CCK2 receptors. The activity of eugenin on splenocytes suggests that it is an immunomodulator peptide which plays a role in the protection of pouch young.
Tianfang Wang - One of the best experts on this subject based on the ideXlab platform.
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fragmentations of m h anions of peptides containing tyrosine Sulfate does the Sulfate Group rearrange a joint experimental and theoretical study
Rapid Communications in Mass Spectrometry, 2013Co-Authors: T Nha T Tran, Tianfang Wang, Sandra Hack, John H. BowieAbstract:RATIONALE To investigate the fragmentations in the negative-ion electrospray mass spectra of peptides containing tyrosine Sulfate. METHODS Possible fragmentation mechanisms were explored using a Waters QTOF2 tandem mass spectrometer in concert with calculations at the CAM-B3LYP/6-311++g(d,p) level of theory. RESULTS The major negative ion formed in the ESI-MS of peptides containing tyrosine Sulfate is [(M − H) − SO3]− and this process normally yields the base peak of the spectrum. The basic backbone cleavages of [(M − H) − SO3]− allowed the sequence of the peptide to be determined. Rearrangement reactions involving the formation of HOSO3− and [(M − H)−H2SO4]− yielded minor peaks with relative abundances ≤ 10% and ≤ 2%, respectively. CONCLUSIONS The mass spectra of the [M − H]− and [(M − H)−SO3]− anions of peptides containing tyrosine Sulfate allowed the position of the tyrosine Sulfate Group to be determined, together with the amino acid sequence of the peptide. Copyright © 2013 John Wiley & Sons, Ltd.
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Fragmentations of [M − H]− anions of peptides containing tyrosine Sulfate. Does the Sulfate Group rearrange? A joint experimental and theoretical study
Rapid communications in mass spectrometry : RCM, 2013Co-Authors: T. T. Nha Tran, Tianfang Wang, Sandra Hack, John H. BowieAbstract:RATIONALE To investigate the fragmentations in the negative-ion electrospray mass spectra of peptides containing tyrosine Sulfate. METHODS Possible fragmentation mechanisms were explored using a Waters QTOF2 tandem mass spectrometer in concert with calculations at the CAM-B3LYP/6-311++g(d,p) level of theory. RESULTS The major negative ion formed in the ESI-MS of peptides containing tyrosine Sulfate is [(M − H) − SO3]− and this process normally yields the base peak of the spectrum. The basic backbone cleavages of [(M − H) − SO3]− allowed the sequence of the peptide to be determined. Rearrangement reactions involving the formation of HOSO3− and [(M − H)−H2SO4]− yielded minor peaks with relative abundances ≤ 10% and ≤ 2%, respectively. CONCLUSIONS The mass spectra of the [M − H]− and [(M − H)−SO3]− anions of peptides containing tyrosine Sulfate allowed the position of the tyrosine Sulfate Group to be determined, together with the amino acid sequence of the peptide. Copyright © 2013 John Wiley & Sons, Ltd.
Régis Daniel - One of the best experts on this subject based on the ideXlab platform.
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Mass spectrometry analysis of the human endosulfatase Hsulf-2
Biochemistry and Biophysics Reports, 2019Co-Authors: Ilham Seffouh, Cédric Przybylski, Amal Seffouh, Rana El Masri, Romain R Vivès, Florence Gonnet, Régis DanielAbstract:The human 6-O-endosulfatases HSulf-1 and -2 catalyze the region-selective hydrolysis of the 6-O-Sulfate Group of the glucosamine residues within Sulfated domains of heparan Sulfate, thereby ensuring a unique and original post-biosynthetic modification of the cell surface proteoglycans. While numerous studies point out the role of HSulf-2 in crucial physiological processes as well as in pathological conditions particularly in cancer, its structural organization in two chains and its functional properties remain poorly understood. In this study, we report the first characterization by mass spectrometry (MS) of HSulf-2. An average molecular weight of 133,115 Da was determined for the whole enzyme by MALDI-TOF MS, i.e. higher than the naked amino acid backbone (98,170 Da), highlighting a significant contribution of post-translational modifications. The HSulf-2 protein sequence was determined by Nano-LC-MS/MS, leading to 63% coverage and indicating at least four N-glycosylation sites at Asn 108, 147, 174 and 217. These results provide a platform for further structural investigations of the HSulf enzymes, aiming at deciphering the role of each chain in the substrate binding and specificities and in the catalytic activities.
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Isomer separation and effect of the polymerization degree on the gas-phase structure of chondroitine Sulfate oligosaccharides analyzed by ion mobility-tandem mass spectrometry
2016Co-Authors: Salomé Poyer, Chrystel Lopin-bon, Jean-claude Jacquinet, Jean-yves Salpin, Régis DanielAbstract:Chondroitin Sulfate (CS) glycosaminoglycans (GAG) are bioactive Sulfated polysaccharides comprising 40-200 Sulfated repeating units of D-glucuronic acid (D-GlcA) and 2-acetamido-2-deoxy-D-galactose (D-GalNac) Sulfated at various positions. D-GalNac may contain a 6-O-Sulfate Group and/or a 4-O-Sulfate Group, and D-GlcA may be Sulfated at the 2- or 3-O position, leading thus to a huge diversity of the CS sequence. Being present in the brain, articulations, placenta, and immune system, CS play critical roles in various physiological processes. In this context, development of efficient analytical methods for the investigation of CS sulfation patterns is of high necessity to associate these biological functions with precisely Sulfated CS structures.Due to their high negative charge density and heterogeneous sulfation pattern, CS oligosaccharides are fragile and challenging to analyze. In this context, MS characterization of synthetics oligosaccharides of chondroitin Sulfated in position 4 (CS-A), 6 (CS-C) or in positions 4 and 6 (CS-E) of the D-GalNac unit was carried out. Isomer separation of di-, tetra- and hexa-CS-A and CS-C was investigated using both MS/MS and IMS-MS. The effects on the gas-phase structure of the polymerization degree and number of Sulfate moiety were studied. Diagnostic ion products were identified from di-, tetra and hexa-CS-A and CS-C alkali adduct isomers allowing a non-ambiguous identification of these compounds. By contrast, MS/MS spectra of deprotonated species of CS-A and CS-C did not show specific ion product. Isomers differentiation by IMS-MS was achieved only for hexa-CS-A and CS-C from the [CS−6H+3Cs]3− species. Finally, influence of polymerization degree and Sulfate Group position on the gas phase conformation was investigated. For the same charge state mono- and di-Sulfated species linearly evolved in function of the side chain. Increase in CCS values with polymerization degree is more important for mono-Sulfated species than for CS-E when the charge density increases. These data can be integrated in biological phenomenon involving CS.
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Differentiation of the fucoidan bulding blocks Sulfated l-fucose isomers by electrospray ionization mass spectrometry, hyphenated capillary electrophoresis and theoretical molecular calculations
Carbohydrate Research, 2006Co-Authors: Bérangère Tissot, Jean-yves Salpin, Michael Martinez, Marie-pierre Gaigeot, Régis DanielAbstract:α-l-Fucose, the monosaccharide component of fucoidan, is found in the polysaccharide mainly as its Sulfated form where Sulfate Groups are in position 2 and/or 4 and/or 3. The correlation between biological activities and structure of fucoidan requires the determination of the sulfation pattern of the fucose residues. Therefore, it is of importance to discriminate between the isobaric Sulfated fucose isomers. For this purpose, the three isomers 2-O-, 3-O-, and 4-O-Sulfated fucose have been analyzed using electrospray ion trap mass spectrometry and capillary electrophoresis. The results reported herein show that it is possible to differentiate between these three positional isomers of Sulfated fucose based on their fragmentation pattern upon MS/MS experiments. 3-O-Sulfated fucose was characterized by the loss of the hydrogenoSulfate anion HSO4- as the main fragmentation product, while the two other isomers 2-O-, and 4-O-Sulfated fucose exhibited cross-ring fragmentation yielding to distinctive 0,2X and 0,2A daughter ion, respectively. A computational study of the conformation of the Sulfated fucose isomers was carried out providing an understanding of the fragmentation pattern with respect to the position of the Sulfate Group.
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Regioselective desulfation of Sulfated L-fucopyranoside by a new sulfoesterase from the marine mollusk Pecten maximus: application to the structural study of algal fucoidan (Ascophyllum nodosum).
European journal of biochemistry, 2001Co-Authors: Régis Daniel, Olivier Berteau, Lionel Chevolot, Anne Varenne, Pierre Gareil, Nicole GoasdoueAbstract:The study of the structural bases of the biological properties of algal fucoidan (Ascophyllum nodosum) led us to look for enzymes able to modify this Sulfated polysaccharide. In this context, we found a sulfoesterase activity in the digestive glands of the common marine mollusk Pecten maximus, which is active on fucoidan. This sulfoesterase activity was shown by capillary electrophoresis and 13C-1H NMR (500 MHz) analysis of the enzymatic hydrolysis of the fucoidan, of fucoidan oligosaccharides and of Sulfated fucose isomers. We report the exhaustive list of all proton and carbon chemical shifts for each of the three isomers of Sulfated-l-fucose (including of their alpha/beta anomers), i.e. the 2-O-, 3-O- and 4-O-Sulfated fucose, which have been useful reference values for the assignments of NMR spectra of fucoidan oligosaccharides upon enzymatic desulfation. Our results demonstrated a high regioselectivity for this sulfoesterase, which hydrolyzes only the Sulfate Group at the 2-O position of the fucopyranoside. Therefore, this sulfoesterase is a helpful tool in the structure-activity study of the fucoidan, as the literature data suggest that the 2-O-sulfation level play a central role in the biological properties of the polysaccharide.
Sandra Hack - One of the best experts on this subject based on the ideXlab platform.
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fragmentations of m h anions of peptides containing tyrosine Sulfate does the Sulfate Group rearrange a joint experimental and theoretical study
Rapid Communications in Mass Spectrometry, 2013Co-Authors: T Nha T Tran, Tianfang Wang, Sandra Hack, John H. BowieAbstract:RATIONALE To investigate the fragmentations in the negative-ion electrospray mass spectra of peptides containing tyrosine Sulfate. METHODS Possible fragmentation mechanisms were explored using a Waters QTOF2 tandem mass spectrometer in concert with calculations at the CAM-B3LYP/6-311++g(d,p) level of theory. RESULTS The major negative ion formed in the ESI-MS of peptides containing tyrosine Sulfate is [(M − H) − SO3]− and this process normally yields the base peak of the spectrum. The basic backbone cleavages of [(M − H) − SO3]− allowed the sequence of the peptide to be determined. Rearrangement reactions involving the formation of HOSO3− and [(M − H)−H2SO4]− yielded minor peaks with relative abundances ≤ 10% and ≤ 2%, respectively. CONCLUSIONS The mass spectra of the [M − H]− and [(M − H)−SO3]− anions of peptides containing tyrosine Sulfate allowed the position of the tyrosine Sulfate Group to be determined, together with the amino acid sequence of the peptide. Copyright © 2013 John Wiley & Sons, Ltd.
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Fragmentations of [M − H]− anions of peptides containing tyrosine Sulfate. Does the Sulfate Group rearrange? A joint experimental and theoretical study
Rapid communications in mass spectrometry : RCM, 2013Co-Authors: T. T. Nha Tran, Tianfang Wang, Sandra Hack, John H. BowieAbstract:RATIONALE To investigate the fragmentations in the negative-ion electrospray mass spectra of peptides containing tyrosine Sulfate. METHODS Possible fragmentation mechanisms were explored using a Waters QTOF2 tandem mass spectrometer in concert with calculations at the CAM-B3LYP/6-311++g(d,p) level of theory. RESULTS The major negative ion formed in the ESI-MS of peptides containing tyrosine Sulfate is [(M − H) − SO3]− and this process normally yields the base peak of the spectrum. The basic backbone cleavages of [(M − H) − SO3]− allowed the sequence of the peptide to be determined. Rearrangement reactions involving the formation of HOSO3− and [(M − H)−H2SO4]− yielded minor peaks with relative abundances ≤ 10% and ≤ 2%, respectively. CONCLUSIONS The mass spectra of the [M − H]− and [(M − H)−SO3]− anions of peptides containing tyrosine Sulfate allowed the position of the tyrosine Sulfate Group to be determined, together with the amino acid sequence of the peptide. Copyright © 2013 John Wiley & Sons, Ltd.
Vladimir M. Petruševski - One of the best experts on this subject based on the ideXlab platform.
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Vibrational spectra of hexaaqua complexes. X. Raman and IR studies of the Sulfate Group disorder in α-alums
Journal of Molecular Structure, 2001Co-Authors: Vladimir M. Petruševski, Vladimir Ivanovski, Bojan Šoptrajanov, M ZugikAbstract:Abstract Earlier X-ray diffraction and Raman spectroscopic studies indicated that the Sulfate Groups in some α-alums are orientationally disordered. The current studies of the Raman and IR spectra of various alums give evidence that the disorder is indeed present in a number of Sulfate α-alums. This is best manifested through the appearance of surplus bands in the spectral regions of the symmetric (Raman) and antisymmetric (IR) stretching vibrations of the Sulfate anion. It was reconfirmed that the extent of disorder is cation-sensitive, the smaller the univalent cation, the larger the disorder. The spectroscopic results are in an excellent agreement with the crystallographic ones. A Sulfate Group disorder was detected in Sulfate-doped selenate alums as well but no positive spectroscopic evidence was found for a selenate Group disorder, again in agreement with the crystallographic results for pure selenate alums.
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structure of the alums i on the Sulfate Group disorder in the α alums
Acta Crystallographica Section B-structural Science, 2000Co-Authors: S C Nyburg, Jon W Steed, Slobotka Aleksovska, Vladimir M. PetruševskiAbstract:The crystal structures at room (296 K) and low (173 K) temperature of several α-alums have been refined by single-crystal X-ray structure analysis. Many α-alums of known structure are disordered, the Sulfate anions occupying one of two possible sites. All those studied here exhibited such disorder and the relative occupancies of the two sites are in excellent agreement with those obtained by Raman spectroscopy, where the ν1(SO4) mode is seen as a doublet owing to the presence of two different types of Sulfate ion. No phase transitions were noted on cooling but there is less disorder.
