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1.
Clin Med Insights Case Rep ; 17: 11795476241242265, 2024.
Article in English | MEDLINE | ID: mdl-38559382

ABSTRACT

Infertility affects 15% of couples in reproductive age worldwide. In women in particular, infertility can be caused by various abnormalities, with polycystic ovary syndrome (PCOS) being the most common. Currently, there are many assisted reproductive techniques (ART) available to combat the burden of infertility. However, positive results are not guaranteed. The administration of inositol has been shown to increase positive reproductive outcomes in women undergoing ART. Here we present a series of clinical cases in which women with a history of infertility and previously failed ART, supplemented with a specific 3.6:1 MYO:DCI ratio, antioxidants, vitamins, and minerals for a period of 1 to 3 months before undergoing in vitro fertilization (IVF). In this series of case reports, we provide preliminary evidence that supplementation with a specific 3.6:1 MYO to DCI ratio, as well as antioxidants, vitamins, and minerals may contribute positively to female fertility in women undergoing IVF, with a history of primary or secondary infertility and previously failed ART.

2.
Rapid Commun Mass Spectrom ; 16(1): 27-34, 2002.
Article in English | MEDLINE | ID: mdl-11754244

ABSTRACT

A strategy for determination of O-glycosylation site(s) in glycopeptides has been developed using model compounds obtained by enzymatic glycosylation (by human GaNTase-T2 isoform) on peptides derived from the human MUC5AC mucin tandem repeat motif. The beta-elimination-addition reaction (using dimethylamine and concomitantly ethanethiol) on the formerly glycosylated sites through a Michael-type condensation produced efficient deglycosylation with appropriate chemical modification. After N-terminal derivatization by a phosphonium group, peptide sequencing was then carried out by nanospray tandem mass spectrometry experiments. The highly predictable fragmentation pathways of these fixed-charge phosphonium derivatives enable straightforward recognition of glycosylation site(s) based on the mass increment of +44 Da for originally glycosylated threonine compared to the mass of fragments containing nonglycosylated residues.


Subject(s)
Glycopeptides/analysis , Mucins/chemistry , Amino Acid Sequence , Catalysis , Dimethylamines , Glycosylation , Humans , Molecular Sequence Data , Spectrometry, Mass, Electrospray Ionization , Tandem Repeat Sequences
3.
J Chromatogr A ; 873(2): 185-94, 2000 Mar 24.
Article in English | MEDLINE | ID: mdl-10757296

ABSTRACT

Reversed-phase high-performance liquid chromatography coupled with electrospray ionization mass spectrometry was used to improve the preparation of three opioid peptides (Leu-Val-Val-hemorphin-7, Val-Val-hemorphin-7 and Val-Val-hemorphin-4) resulting from bovine hemoglobin peptic hydrolysates. Optimal conditions for the preparation of these peptides were determined thanks to their kinetic studies of appearance in the course of peptic hydrolyses as a function of degree of hydrolysis of hemoglobin. We propose a low degree of hydrolysis (3%) to prepare Leu-Val-Val-hemorphin-7, a mean degree of hydrolysis (11%) to prepare Val-Val-hemorphin-7 and a high degree of hydrolysis (21%) to prepare Val-Val-hemorphin-4.


Subject(s)
Chromatography, High Pressure Liquid/methods , Hemoglobins/chemistry , Mass Spectrometry/methods , Opioid Peptides/chemistry , Amino Acid Sequence , Animals , Cattle , Hydrolysis , Kinetics
4.
J Dairy Res ; 67(4): 551-9, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11131068

ABSTRACT

Goat whey was hydrolysed by pepsin in an ultrafiltration membrane enzymic reactor coupled with a 30 kDa mineral membrane. Peptides collected in the permeate were resolved using reversed-phase HPLC. Their sequences were determined by amino acid analysis, second order derivative spectra analysis and mass spectrometry. Owing to the resistance of beta-lactoglobulin (beta-lg) towards pepsin, the majority of peptides identified were derived from alpha-lactalbumin (alpha-la). Pepsin showed a broad specificity of hydrolysis sites and generated a wide range of products from dipeptides to very large peptides containing disulphide bridges. The molecular masses of peptides resulting from alpha-la degradation were between 150 and 6900 Da: 36% were < 600 Da. 24% were 600-2000 Da and 40% were > 2000 Da.


Subject(s)
Goats , Lactalbumin/chemistry , Milk Proteins/metabolism , Pepsin A/metabolism , Amino Acid Sequence , Amino Acids/analysis , Animals , Chromatography, High Pressure Liquid , Hydrolysis , Lactalbumin/isolation & purification , Mass Spectrometry , Membranes, Artificial , Milk Proteins/chemistry , Molecular Weight , Reverse Transcriptase Polymerase Chain Reaction , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Ultrafiltration , Whey Proteins
5.
Prep Biochem Biotechnol ; 29(2): 189-202, 1999 May.
Article in English | MEDLINE | ID: mdl-10231897

ABSTRACT

Bovine whey hydrolysate has been developed and applied to areas such as nutrition, culture media, and isolation of bioactive peptides. In order to produce such a type of hydrolysate, it is possible to use goat whey, which constitutes also a food processing by-product. Enzymatic hydrolysis of goat whey by pepsin was carried out in a continuous ultrafiltration reactor. The permeate contained peptide hydrolysate that was resolved by RPHPLC. Second order derivative spectroscopy, amino acid analysis, and mass spectrometry revealed the presence of a biologically active peptide called alpha-lactorphin. This constitutes preliminary information about goat whey enzymatic degradation for future applications.


Subject(s)
Milk Proteins/chemistry , Oligopeptides/chemical synthesis , Amino Acid Sequence , Animals , Chromatography, High Pressure Liquid , Goats , Hydrolysis , Mass Spectrometry , Milk/chemistry , Oligopeptides/analysis , Spectrophotometry, Ultraviolet , Whey Proteins
6.
Biochem J ; 333 ( Pt 3): 749-56, 1998 Aug 01.
Article in English | MEDLINE | ID: mdl-9677337

ABSTRACT

Human inter-alpha-inhibitor (IalphaI) is a plasma serine-proteinase inhibitor. It consists of three polypeptide chains covalently linked by a glycosaminoglycan chain: a light chain named bikunin carrying the anti-proteinase activity and two heavy chains, H1 and H2, which exhibit specific properties, e.g. they interact with hyaluronan thus stabilizing the extracellular matrix. In this study, using matrix-assisted laser desorption ionization-time-of-flight MS and amino acid sequencing of tryptic peptides, we provide a detailed analysis of the glycosylation pattern of both heavy chains. H1 carries two complex-type N-glycans of predominantly biantennary structure linked to asparagine residues at positions 256 and 559 respectively. In contrast, the oligosaccharides attached to H2 are a complex-type N-glycan in the N-terminal region of the protein (Asn64) and three to four type-1 core-structure O-glycans mono- or di-sialylated, clustered in the C-terminal region. We propose that these O-glycans might function as a recognition signal for the H2 heavy chain. The biological implications of this hypothesis, notably for the biosynthetic pathway of IalphaI, are discussed.


Subject(s)
Alpha-Globulins/metabolism , Serine Proteinase Inhibitors/metabolism , Alpha-Globulins/chemistry , Amino Acid Sequence , Carbohydrate Sequence , Chromatography, High Pressure Liquid , Glycopeptides/chemistry , Glycopeptides/metabolism , Glycosylation , Humans , Macromolecular Substances , Molecular Sequence Data , Serine Proteinase Inhibitors/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
7.
Clin Chim Acta ; 252(2): 109-22, 1996 Aug 30.
Article in English | MEDLINE | ID: mdl-8853559

ABSTRACT

Carnitine levels and acylcarnitine profiles in a patient with mild multiple acyl-CoA dehydrogenase deficient beta-oxidation were compared with control results. Whereas blood and urine total carnitine levels were moderately decreased, blood esterified carnitine levels in the patient were about 2-fold higher than in controls. Urinary acylcarnitine profiles presented with a larger variety of carnitine esters than in controls and included propionylcarnitine, butyrylcarnitine, 2-methylbutyrylcarnitine, hexanoylcarnitine and octanolycarnitine. Total carnitine levels in body fluids were similarly affected by chronic oral L-carnitine administration in patient and controls. By contrast, esterified carnitine level increase was 2-fold more important in controls than in patient. Whereas no qualitative changes in urinary acylcarnitine profiles were induced by L-carnitine therapy in controls, several alterations of these profiles were observed in the patient. The effect of starvation on metabolites was also studied, especially beta-oxidation rates assessed by free fatty acids to 3-hydroxybutyric acid ratios in blood from the patient in the untreated and L-carnitine treated states. In the L-carnitine-supplemented patient, the effect of starvation on the time course of carnitine levels and acylcarnitine profiles could also be documented. The ability of chronic oral L-carnitine administration to remove relatively less important amounts of acylcarnitines in the patient than in controls is further discussed, as well as qualitative alterations of acylcarnitine profiles induced by this therapy in the pathological condition.


Subject(s)
Acyl-CoA Dehydrogenases/metabolism , Carnitine/therapeutic use , Fasting , Metabolism, Inborn Errors/drug therapy , Acyl-CoA Dehydrogenase , Acyl-CoA Dehydrogenases/deficiency , Carnitine/blood , Carnitine/urine , Humans , Infant , Metabolism, Inborn Errors/blood , Metabolism, Inborn Errors/urine , Oxidation-Reduction
8.
Eur J Biochem ; 232(2): 449-57, 1995 Sep 01.
Article in English | MEDLINE | ID: mdl-7556193

ABSTRACT

Treatment of bean cell walls with a pure endopolygalacturonase of the bean pathogen Colletotrichum lindemuthianum race beta released oligogalacturonides and pectic fragments which were separated according to their charge and size. Among galacturonic-acid-containing components, elicitors and suppressors of the plant cell wall hydroxyproline-rich glycoprotein (HRGP) were recovered. Two active small oligogalacturonides with degrees of polymerization of 2 and 3 were characterized by high-performance anion-exchange-chromatography pulsed amperometric detection and fast-atom-bombardment mass spectrometry; they elicited 40-70% hydroxyproline increase within 48 hours at 450 nmol/bean cutting. In contrast, pectic fragments of higher molecular mass, predominantly composed of galacturonic acid and containing sugars typical of the rhamnogalacturonan II domain of pectic polysaccharides, had the ability to substantially suppress hydroxyproline deposition. Maximum suppressor activity, 30-40% below the activity of the control, occurred in 48 hours. In view of the low one-cycle turnover of these proteins in the cell wall and of their structural role, these changes might significantly affect cell wall properties. Elicitation and/or suppression of hydroxyproline were correlated to modifications of HRGP-extensin gene expression. Northern-blot analysis of RNA showed that changes in the transcript intensity became clearly visible within the first 12 hours after the start of either treatment. The results show that pectic components of the plant extracellular matrix have the potential to regulate wall matrix biogenesis. Implications of this finding in plant defense and development are discussed.


Subject(s)
Glycoproteins/metabolism , Plant Proteins/metabolism , Polygalacturonase/pharmacology , Cell Wall/drug effects , Cell Wall/metabolism , Fabaceae/genetics , Fabaceae/metabolism , Fabaceae/microbiology , Gene Expression Regulation, Plant/drug effects , Glycoproteins/genetics , Mitosporic Fungi/enzymology , Mitosporic Fungi/pathogenicity , Oligosaccharides/chemistry , Oligosaccharides/isolation & purification , Oligosaccharides/pharmacology , Pectins/isolation & purification , Pectins/pharmacology , Plant Proteins/genetics , Plants, Medicinal , Signal Transduction , Solubility
9.
Santo Domingo; Fundación Méjia Ricart-Guzmán Boom; 5 ed; 1995. 400 p. (Textos básicos, 1).
Monography in Spanish | LILACS | ID: lil-236747

Subject(s)
Psychology
10.
Eur J Pediatr ; 153(8): 598-603, 1994 Aug.
Article in English | MEDLINE | ID: mdl-7957409

ABSTRACT

We describe on a 3-year-old child referred for evaluation and therapy of a cerebral vascular accident with residual hemiplegia and partial epilepsy. Metabolic investigations initially showed normal urinary organic acids as well as normal blood and urinary amino acids. Blood carnitine fractions had been pathological and a secondary carnitine deficiency was diagnosed and treated by oral L-carnitine supplementation. During carnitine treatment, abnormal urinary acylcarnitine profiles were noticed with excessive amounts of several carnitine esters including propionylcarnitine, butyryl- and/or isobutyryl-carnitine, isovaleryl- and/or 2-methylbutyryl-carnitine, hexanoylcarnitine and octanoylcarnitine. Subsequently, an urinary organic acid profile suggestive of glutaric aciduria type II was recorded during a clinical decompensation crisis. Morphological and biochemical studies on skeletal muscle and skin fibroblasts were performed and confirmed the existence of a defect of the mitochondrial beta-oxidation pathways with lipidic myopathy, reduced palmitate and octanoate oxidation rates in cultured fibroblasts. Glutaric aciduria type II increases the list of metabolic disorders characterized by hemiplegia and other sequelae of brain ischaemia such as stroke-like episode, seizures, aphasia, ataxia and myoclonia, similar to those seen in MELAS.


Subject(s)
Cerebrovascular Disorders/complications , Fatty Acid Desaturases/deficiency , Hemiplegia/complications , MELAS Syndrome/etiology , Mitochondria/metabolism , Carnitine/blood , Child, Preschool , Glutarates/urine , Humans , MELAS Syndrome/diagnosis , MELAS Syndrome/pathology , Male , Oxidation-Reduction
11.
Biol Mass Spectrom ; 23(5): 283-94, 1994 May.
Article in English | MEDLINE | ID: mdl-8204685

ABSTRACT

Mass spectrometry is a very powerful tool in the identification of chemical modifications of proteins and peptides. Often these modifications cannot be determined by conventional techniques. This report describes the combined use of electrospray ionization mass spectrometry and fast atom bombardment mass spectrometry to complete the primary structure of proteins and peptides. Examples illustrate how mass spectrometry is used to locate sites of phosphorylation, methylation and acetylation, and identify blocking groups and unexpected side reactions such as deamidation or alkylation.


Subject(s)
Peptides/chemistry , Protein Processing, Post-Translational , Proteins/chemistry , Acetylation , Amino Acid Sequence , Amino Acids/analysis , Amino Acids/chemistry , Animals , Cattle , Cyclization , Electrochemistry , Erythrocytes/chemistry , Histones/chemistry , Male , Methylation , Molecular Sequence Data , Phosphorylation , Protamines/chemistry , Sheep , Spectrometry, Mass, Fast Atom Bombardment , Thymus Gland/chemistry , Xenopus laevis
12.
Biochem Biophys Res Commun ; 189(1): 101-10, 1992 Nov 30.
Article in English | MEDLINE | ID: mdl-1449465

ABSTRACT

Two opioid peptides were isolated from a bovine hemoglobin hydrolysate, by use of gel permeation (GP) and reverse phase (RP) high performance liquid chromatography (HPLC). Their primary structure and accurate molecular weights, determined by amino acid analysis and fast atom bombardment (FAB) mass spectrometry, were identical to fragments 31-40 (LVV-hemorphin-7) and 32-40 (VV-hemorphin 7) of the beta-chain of bovine hemoglobin. The same fragments occur in human hemoglobin in positions 32-41 and 33-41 of the beta-chain, respectively. The opioid potency of these peptides, exhibited by use of electrically stimulated muscle of isolated guinea-pig ileum (GPI), were significant and comparable with some others previously described. In addition, the location of the two opioid peptides, VV-hemorphin-7 and LVV-hemorphin-7, revealed the existence of a "strategic zone" both in the bovine and human beta-chains of hemoglobin.


Subject(s)
Endorphins/isolation & purification , Hemoglobins/chemistry , Muscle Contraction/drug effects , Peptide Fragments/isolation & purification , Amino Acid Sequence , Animals , Cattle , Chromatography, Gel , Chromatography, High Pressure Liquid , Endorphins/chemistry , Endorphins/pharmacology , Guinea Pigs , Hemoglobins/isolation & purification , Hemolysis , Hydrolysis , Ileum/drug effects , Ileum/physiology , In Vitro Techniques , Molecular Sequence Data , Muscle, Smooth/drug effects , Muscle, Smooth/physiology , Peptide Fragments/chemistry , Peptide Fragments/pharmacology , Spectrometry, Mass, Fast Atom Bombardment , Ultrafiltration
13.
FEBS Lett ; 299(1): 75-9, 1992 Mar 24.
Article in English | MEDLINE | ID: mdl-1544478

ABSTRACT

A bradykinin potentiating peptide was isolated from a peptic bovine hemoglobin hydrolysate, by the use of reversed-phase high-performance liquid chromatography (RP-HPLC). Its primary structure, determined by fast atom bombardment (FAB) and tandem mass spectrometry (MS/MS), was identical to fragment 129-134 of the alpha-chain of bovine hemoglobin. The bradykinin potency of this peptide, as exhibited by the guinea-pig ileum contraction, was significant and comparable with some others previously described.


Subject(s)
Bradykinin/pharmacology , Hemoglobins/chemistry , Amino Acid Sequence , Animals , Cattle , Chromatography, High Pressure Liquid , Guinea Pigs , Hemoglobins/pharmacology , Molecular Sequence Data , Peptide Fragments/chemistry , Peptide Fragments/pharmacology , Spectrometry, Mass, Fast Atom Bombardment
14.
Carbohydr Res ; 221: 209-17, 1991 Dec 16.
Article in English | MEDLINE | ID: mdl-1816919

ABSTRACT

Collision-activated dissociation (c.a.d.) of sodium adducts of molecular ion species have been carried out on methylated beta-D-Galp-(1----4)-beta-D-GlcpNAc- (1----3)-beta-D-Galp-(1----4)-D-Glcp (1), beta-D-Galp-(1----3)-beta-D-GlcpNAc-(1----3)-beta-D-Galp-(1----4)-D-Glcp (2), alpha-D-NeuAc-(2----3)-beta-D-Galp-(1----3)-beta-D-GlcpNAc-(1----3)-beta -D-Galp - (1----4)-D-Glcp (3), alpha-D-NeuAc-(2----6)-beta-D-Galp-(1----4)-beta-D-GlcpNAc-(1----3)-beta -D-Galp - (1----4)-D-Glcp (4), and alpha-D-NeuAc-(2----6)-beta-D-Galp-(1----4)-beta-D-GlcpNAc-(1----2)-alph a-D- Manp-(1----3)-beta-D-Manp-(1----4)-D-GlcpNAc (5). The numerous daughter ions reflect the sequences, clearly differentiate (1----3) and (1----4) linkages, and discriminate between alpha-NeuAc-(2----3) and alpha-NeuAc-(2----6) linkages.


Subject(s)
Oligosaccharides/chemistry , Sialic Acids/chemistry , Carbohydrate Sequence , Isomerism , Methylation , Molecular Sequence Data , Spectrometry, Mass, Fast Atom Bombardment
15.
Eur J Biochem ; 198(3): 627-33, 1991 Jun 15.
Article in English | MEDLINE | ID: mdl-2050144

ABSTRACT

Immunocytochemical studies have shown that peptides like Phe-Met-Arg-Phe-NH2 (FMRFamide) are widely distributed throughout the nervous system of three Nereidae. In Nereis diversicolor we have isolated these peptides from an extract of total worms by affinity chromatography and two steps of reversed-phase high-performance liquid chromatography. The sequences of the purified peptides have been determined by amino acid sequencing and on the basis of their reactivity with an anti-FMRFamide serum specific for the determinant Arg-Phe-NH2. Two primary structures have been established: Phe-Thr-Arg-Phe-NH2 (FTRFamide) and PHe-Met-Arg-Phe-NH2 (FMRFamide). Furthermore a methionine sulfoxide derivative of the FMRFamide has been identified. We have synthesized the FTRFamide peptide and in all cases, the native peptides were indistinguishable from the synthetic counterparts. The structure of the two native peptides and of the methionyl sulfoxide derivate have been confirmed by fast-atom-bombardment and tandem mass spectrometry.


Subject(s)
Neuropeptides/isolation & purification , Polychaeta/analysis , Amino Acid Sequence , Animals , Chromatography, Affinity , Chromatography, High Pressure Liquid , FMRFamide , Immunoenzyme Techniques , Molecular Sequence Data , Neuropeptides/chemical synthesis , Neuropeptides/chemistry , Spectrometry, Mass, Fast Atom Bombardment
16.
Anal Biochem ; 184(2): 235-43, 1990 Feb 01.
Article in English | MEDLINE | ID: mdl-2327569

ABSTRACT

Supercritical fluid chromatography separations and supercritical fluid chromatography chemical ionization mass spectrometry analysis of permethylated and pertrimethylsilylated oligosaccharides are reported. Supercritical fluid chromatography was carried out using a DB-5 coated capillary column with carbon dioxide as a mobile phase. Peralkylated oligosaccharides were detected by flame ionization and by chemical ionization mass spectrometry using the GC interface. Analysis of permethylated malto-oligosaccharides, as well as oligomannosides from mannosidosis, was achieved by chemical ionization mass spectrometry with ammonia and provided the pseudo-molecular ions (M+H)+ and (M+NH4)+, in addition to some other fragments which allow interpretations of the structure of different oligosaccharides. The good resolution and sensitivity obtained emphasize the potential of supercritical fluid chromatography mass spectrometry for rapid separations and analysis of complex glycan mixtures.


Subject(s)
Chromatography , Gas Chromatography-Mass Spectrometry , Oligosaccharides/isolation & purification , Gas Chromatography-Mass Spectrometry/instrumentation , Polysaccharides/isolation & purification
17.
J Chromatogr ; 481: 221-31, 1989 Nov 03.
Article in English | MEDLINE | ID: mdl-2592493

ABSTRACT

Gel-permeation high-performance liquid chromatography (HPLC) and reversed-phase HPLC were used to separate a mixture of peptides, produced at pilot-plant scale by peptic hydrolysis of bovine haemoglobin. Volatile buffers were employed in both HPLC techniques in order to get an easy recovery of peptides for further applications. The method is more rapid than low-pressure gel filtration. Amino acid analysis and fast atom bombardment mass spectrometry confirmed the purity, and allowed accurate molecular weights to be determined, for isolated peptides. These data demonstrate that such efficient techniques, usually used to resolve hydrolysates obtained in batch with pure substrates and highly specific enzymes, can be employed to resolve complex enzymatic hydrolysates of crude protein.


Subject(s)
Hemoglobins/metabolism , Peptides/analysis , Amino Acid Sequence , Amino Acids/analysis , Animals , Cattle , Chromatography, Gel , Hydrolysis , Mass Spectrometry , Molecular Sequence Data , Molecular Weight , Spectrophotometry, Ultraviolet
18.
Eur J Biochem ; 182(1): 139-52, 1989 Jun 01.
Article in English | MEDLINE | ID: mdl-2731547

ABSTRACT

The structure of the major O-glycosidically linked neutral and acidic oligosaccharides isolated from human meconium glycoproteins were established. Neutral and acidic oligosaccharides were released by alkaline borohydride treatment, purified by Biogel P-6 and fractionated by high-performance liquid chromatography. This approach resulted in 50 neutral and 30 acidic oligosaccharides. The present study reports the primary structural analysis of five neutral oligosaccharides, ten monosialylated oligosaccharides, one monosialylated monosulfated oligosaccharide and three disialylated oligosaccharides, by permethylation, fast-atom-bombardment mass spectrometry analysis and 400-MHz 1H-NMR spectroscopy. The following structure have not been described previously: (formula; see text) The intestinal glycoproteins of human meconium are characterized as high molecular mass compounds with numerous carbohydrate chains of the mucin type. These mucins are a rich source of carbohydrate structures which express multiple blood group activities and occur as membrane-associated antigens, recognized by hybridoma antibodies [1-4]. A previous study [5] described the structure of fifteen free oligosaccharides derived from catabolism of O- and N-glycans accumulating in new born meconium. In the same group [6] the research has been extended to glycoasparagines with the description of thirteen of them by high resolution 1H-NMR spectroscopy analysis. From O-glycosidically linked glycoproteins, further studies [7] established the structures of nine major monosaccharides to tetrasaccharides obtained after mild acid hydrolysis and base-borohydride degradation from meconium samples of group O secretors. These oligosaccharides were derived from meconium glycopeptides which had been depleted of I- and i-antigen activities. Recently [8], neutral and acidic oligosaccharide-alditols obtained by alkaline borohydride degradation of human meconium glycoproteins have been separated by HPLC on an anion-exchange column. The neutral fraction was further purified by normal-phase and reversed-phase chromatography while acidic fractions were fractionated only by normal-phase chromatography. Thus, we have isolated several low molecular mass oligosaccharides of different size and composition and also isomers which vary in linkage position or anomer configuration. Using methylation analysis, 1H-NMR spectroscopy and fast-atom-bombardment mass spectrometry (FAB-MS), we propose the primary structure for 19 major oligosaccharides.


Subject(s)
Glycoproteins/analysis , Glycosides/analysis , Meconium/analysis , Oligosaccharides/isolation & purification , Binding Sites , Chromatography, Gel , Chromatography, High Pressure Liquid , Humans , Magnetic Resonance Spectroscopy , Mass Spectrometry , Methylation , Molecular Structure
19.
Anal Biochem ; 168(1): 164-70, 1988 Jan.
Article in English | MEDLINE | ID: mdl-3364710

ABSTRACT

Conventional positive fast atom bombardment (FAB) and continuous-flow FAB analysis were carried out with permethylated lacto-N-tetraose. This latter method, a new approach, has been used to analyze a mixture of permethylated oligosaccharides by liquid chromatography-mass spectrometry (LC-MS) with a packed capillary fused-silica column and the continuous-flow probe as interface. Under these conditions, we found the continuous-flow probe to be superior to the conventional probe because its low matrix level increased the signal-to-noise ratio. The analysis of the mixture of permethylated oligosaccharide alditols obtained from hen ovomucoid by LC-MS using the continuous-flow probe as interface is described.


Subject(s)
Oligosaccharides/analysis , Animals , Chickens , Chromatography, Liquid/instrumentation , Chromatography, Liquid/methods , Mass Spectrometry/methods , Methylation , Ovomucin/analysis , Sugar Alcohols/analysis
20.
Carbohydr Res ; 141(1): 41-7, 1985 Aug 15.
Article in English | MEDLINE | ID: mdl-4042112

ABSTRACT

Treatment of dimethyl sulfoxide with butyllithium leads to rapid formation of lithium methylsulfinyl carbanion. The reaction products tend to be significantly freer from impurities when lithium methylsulfinyl carbanion is used rather than sodium or potassium methylsulfinyl carbanion. This reagent gives less background in g.l.c. and thus may be used to methylate micro-quantities of glycoprotein glycans (down to 10 micrograms) without the necessity of identifying methyl ethers by mass spectrometry.


Subject(s)
Dimethyl Sulfoxide , Glycoproteins , Organometallic Compounds , Polysaccharides , Animals , Chickens , Female , Indicators and Reagents , Lithium , Methylation , Oligosaccharides , Ovomucin
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