scholarly journals Retained folates in the rat

1977 ◽  
Vol 164 (3) ◽  
pp. 601-605 ◽  
Author(s):  
P A Barford ◽  
R J Staff ◽  
J A Blair
Keyword(s):  
Folic Acid ◽  
Ion Exchange ◽  
Gel Permeation Chromatography ◽  
Exchange Chromatography ◽  
Chromatographic Behaviour ◽  
Gel Permeation

The retention of radioactivity after doses of 14C- and 3H-labelled folic acid is described. Radioactivity was retained in liver, kidney and gut of rats for some time after administration of the dose. The retained radioactivity could not be displaced by large doses of unlabelled folic acid or unlabelled 5-methyltetrahydrofolate. 14C- and 3H-labbelled folates showed similar chromatographic behaviour onion-exchange chromatography to 5-methyltetrahydrofolate, and on ion-exchange and gel-permeation chromatography to synthetic pteroylhepta-gamma-glutamate.

scholarly journals Separation of a series of chromophores and fluorophores present in elastin

1975 ◽  
Vol 147 (2) ◽  
pp. 215-219 ◽  
Author(s):  
D P Thornhill
Keyword(s):  
Optical Properties ◽  
Ion Exchange ◽  
Fluorescence Spectra ◽  
Cation Exchanger ◽  
Gel Permeation Chromatography ◽  
Protein Molecule ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Intact Protein ◽  
Gel Permeation

Purified elastin was hydrolysed with HCl and manipulated under conditions that minimized oxidation. Gel-permeation chromatography on polyacrylamide gel and ion-exchange chromatography on dextran cation-exchanger each resulted in the separation of a series of yellow fluorescent fractions. These hitherto unreported ampholytes have fluorescence spectra that approximate to that of the intact protein, and account for its characteristic optical properties. Since the coloured fluorophores are confined to enzyme-resistant regions of the protein molecule they appear to have important structural implications.

Quantitative fractionation of casein mixtures by fast protein liquid chromatography

1987 ◽  
Vol 54 (3) ◽  
pp. 369-376 ◽  
Author(s):  
D. Thomas Davies ◽  
Andrew J. R. Law
Keyword(s):  
Liquid Chromatography ◽  
Ion Exchange ◽  
Deae Cellulose ◽  
Gel Permeation Chromatography ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Fast Protein Liquid Chromatography ◽  
Good Resolution ◽  
Gel Permeation

SummaryAlkylation of whole casein samples by reaction with cysteamine and cystamine in a bis-tris-propane–urea buffer (pH 7·0) followed by fast protein liquid chromatography (FPLC) at 20°C on a Mono Q HR5/5 column in the same buffer and using a NaCl gradient led to good resolution of the whole casein into fractions representing (i) γ2- plus γ3-caseins, (ii) κ-caseins, (iii) β-casein, (iv) αs2-caseins and (v) αsl-caseins, together with small amounts of unidentified materials. Quantitatively the FPLC values agreed well with those for αs1-, β-, αs2- and γ2- plus γ3-caseins obtained by ion-exchange chromatography on DEAE cellulose, Whatman DE52 and with those for º-caseins obtained by gel-permeation chromatography on Sephadex G–150.

scholarly journals Folic acid metabolism in vitamin B12-deficient sheep. Effects of injected methionine on liver constituents associated with folate metabolism

1974 ◽  
Vol 142 (1) ◽  
pp. 105-117 ◽  
Author(s):  
Richard M. Smith ◽  
William S. Osborne-White ◽  
Jeffrey M. Gawthorne
Keyword(s):  
Folic Acid ◽  
Ion Exchange ◽  
Vitamin B12 ◽  
Lactobacillus Casei ◽  
Acid Metabolism ◽  
Major Effect ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Folate Metabolism ◽  
Folic Acid Metabolism

1. The effects of injected l-methionine (2g every second day for 28 days) on liver folates and other constituents of liver associated with folate metabolism were studied in vitamin B12-deficient ewes and their pair-fed controls receiving vitamin B12. The dose rate of methionine used was sufficient to restore almost to normal the elevated excretion in the urine of formiminoglutamate in the deficient animals. 2. Liver folates active for Lactobacillus casei, Streptococcus faecalis R and Pediococcus cerevisiae were severely depressed in deficient livers and were partly restored by methionine. Analysis of the folates after ion-exchange chromatography showed that the major effect of methionine was to increase the concentrations of tetrahydrofolates and formyltetrahydrofolates. Methyltetrahydrofolates were also increased, but there was no effect of methionine on the small amounts of incompletely reduced folates present in deficient livers. The folates present were predominantly penta-, hexa- and hepta-glutamates whether or not animals received vitamin B12 or methionine. 3. Concentrations of ATP, NAD+, NADH and NADPH were lower in freeze-clamped liver from vitamin B12-deficient sheep than in liver from pair-fed, vitamin B12-treated sheep. These changes were not affected by methionine which was also without effect on the elevated K+/Na+ ratios found in deficient livers. 4. The livers of vitamin B12-deficient animals contained lower concentrations of choline and higher concentrations of lipid than their pair-fed controls. These effects were reversed by methionine.

Notizen: Über das Vorkom men von Acetylcholinesterase (E.C. 3.1.1.7) in der H äm olym phe der Miesmuschel Mytilus edulis / Occurrence of an Acetylcholinesterase (E.C. 3.1.1.7) in the Haemolymph of the Mussel Mytilus edulis

1976 ◽  
Vol 31 (5-6) ◽  
pp. 333-334 ◽  
Author(s):  
Dettmar von Wachtendonk
Keyword(s):  
Ion Exchange ◽  
Mytilus Edulis ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Gel Permeation

Abstract A Cholinesterase deriving from the hemolymph of the mussel Mytilus edulis was partially purified by use of gel-permeation and ion-exchange chromatography; the specifity to different substrates or inhibitors indicates clearly the occurrence of a “true” acetylcholinesterase.

scholarly journals Two linkage-region fragments isolated from skeletal keratan sulphate contain a sulphated N-acetylglucosamine residue

1990 ◽  
Vol 269 (1) ◽  
pp. 55-59 ◽  
Author(s):  
J M Dickenson ◽  
T N Huckerby ◽  
I A Nieduszynski
Keyword(s):  
Gel Permeation Chromatography ◽  
Anion Exchange Chromatography ◽  
Ester Group ◽  
Intervertebral Discs ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Keratan Sulphate ◽  
Linkage Region ◽  
Gel Permeation ◽  
Electron Micro Probe Analysis

Peptido-keratan sulphate fragments were isolated from the nucleus pulposus of bovine intervertebral discs (6-year-old animals) after chondroitin ABC lyase digestion followed by digestion of A1D1 proteoglycans by diphenylcarbamoyl chloride-treated trypsin and gel-permeation chromatography on Sepharose CL-6B. Treatment of these peptido-keratan sulphate fragments with alkaline NaB3H4 yielded keratan sulphate chains with [3H]galactosaminitol end-labels, and these chains were further purified by gel-permeation chromatography on Sephadex G-50 and ion-exchange chromatography on a Pharmacia Mono-Q column in order to exclude any contamination with O-linked oligosaccharides. The chains were then treated with keratanase, and the digest was chromatographed on a Bio-Gel P-4 column followed by anion-exchange chromatography on a Nucleosil 5 SB column. Two oligosaccharides, each representing 18% of the recovered radiolabel, were examined by 500 MHz 1H-n.m.r. spectroscopy, and shown to have the following structures: [formula: see text] The structure of oligosaccharide (I) confirms the N-acetylneuraminylgalactose substitution at position 3 of N-acetylgalactosamine in the keratan sulphate-protein linkage region found by Hopwood & Robinson [(1974) Biochem. J. 141, 57-69] but additionally shows the presence of a 6-sulphated N-acetylglucosamine. Electron micro-probe analysis specifically confirmed the presence of sulphur in this sample. This sulphate ester group differentiates the keratan sulphate linkage region from similar structures derived from O-linked oligosaccharides [Lohmander, De Luca, Nilsson, Hascall, Caputo, Kimura & Heinegård (1980) J. Biol. Chem. 255, 6084-6091].

Heat-induced changes in sodium Caseinate

1989 ◽  
Vol 56 (3) ◽  
pp. 503-512 ◽  
Author(s):  
Mingruo Guo ◽  
Patrick F. Fox ◽  
Albert Flynn ◽  
Kais S. Mahammad
Keyword(s):  
Light Scattering ◽  
Ion Exchange ◽  
Polyacrylamide Gel Electrophoresis ◽  
Gel Filtration ◽  
Covalent Bond ◽  
Gel Permeation Chromatography ◽  
Sodium Caseinate ◽  
Exchange Chromatography ◽  
Water Ph ◽  
Covalent Bond Formation

SummaryChemical and physical changes that occur in Na caseinate (at 1 or 2% in water, pH 7·0) on heating in the range 120–150 °C were investigated by polyacrylamide gel electrophoresis, ion-exchange and gel-permeation chromatography, light scattering, u.v. spectroscopy, amino acid analysis, and the formation of pH 4·6 and 12% TCA-soluble N and 12% TCA-soluble P. The electropherograms of heated samples were smeared and indistinct suggesting intermolecular aggregation which was not reversed by 6 M-urea or SDS and indicating covalent bond formation; αs2-casein was especially sensitive. Aggregation was confirmed by ion-exchange chromatography and light scattering. Fragmentation of the caseins also occurred on heating, as indicated by the formation of pH 4·6 and 12% TCA-soluble N and by gel filtration. Formation of soluble N and dephosphorylation followed first-order kinetics. Concentrations of available lysine and available methionine were reduced by 10–15% on heating at 140 °C for 30min; chemical assays for arginine and tryptophan indicated increases, suggesting interference. Ultraviolet spectroscopy indicated a slight apparent increase in aromatic residues after heating at 140 °C for up to 60 min.

Rapid analysis of bilirubin in neonatal serum. I. The binding of bilirubin to albumin.

1979 ◽  
Vol 25 (9) ◽  
pp. 1608-1612 ◽  
Author(s):  
K C Lu ◽  
K M Gooding ◽  
F E Regnier
Keyword(s):  
Serum Proteins ◽  
Binding Capacity ◽  
Gel Permeation Chromatography ◽  
Exchange Chromatography ◽  
Serum Samples ◽  
Binding Characteristics ◽  
Quenching Analysis ◽  
Gel Permeation ◽  
Bilirubin Binding

Abstract Evaulation of the severity of jaundice in the neonate may be determined by measuring the reserve binding capacity of serum proteins for free bilirubin. Determination of protein-bound bilirubin has been labor intensive, necessitating multiple runs on gel-permeation chromatography columns or, more recently, enzyme assays or fluorescence quenching analysis. We present a method for quantitation of free bilirubin and of bilirubin-binding capacity of serum by liquid chromatography. A gel-permeation column binds free bilirubin while allowing passage and quantitation of protein-bound bilirubin. Subsequent injection of a desorbing agent releases the adsorbed bilirubin from the column, permitting quantitation of free bilirubin. Bound and free serum bilirubin may be determined directly in less than 15 min using 10 microL of serum. The binding of bilirubin to neonatal serum is seen to be quite different from the binding to adult serum. Ion-exchange chromatography of adult and neonatal serum samples shows that their protein profiles are radically different. This difference probably accounts for the binding characteristics.

scholarly journals Xyloglucan endotransglycosylase: evidence for the existence of a relatively stable glycosyl–enzyme intermediate

1998 ◽  
Vol 330 (3) ◽  
pp. 1475-1480 ◽  
Author(s):  
Zdena SULOVÁ ◽  
Miriam TAKÁČOVÁ ◽  
M. Nancy STEELE ◽  
C. Stephen FRY ◽  
Vladimír FARKAŠ
Keyword(s):  
Complex Formation ◽  
Gel Permeation Chromatography ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Glycosidic Bond ◽  
Xyloglucan Endotransglycosylase ◽  
Anomeric Configuration ◽  
Gel Permeation ◽  
Covalently Linked ◽  
Enzyme Intermediate

Xyloglucan endotransglycosylases (XETs) catalyse the breakdown of xyloglucan molecules predominantly by transglycosylation. In this process, fragments of cleaved polysaccharide are preferentially transferred to other xyloglucan molecules or their oligosaccharide subunits, with overall retention of the anomeric configuration of the glycosidic bond. In accordance with the theory, we propose that the cleavage and re-formation of the glycosidic bond in xyloglucan involves the formation of a glycosyl-enzyme intermediate which decomposes by transfer of the glycosyl moiety to a suitable carbohydrate acceptor. XETs from nasturtium seed cotyledons, mung bean hypocotyls and cauliflower florets interacted with xyloglucan to form complexes of high Mr as judged by gel-permeation chromatography. The nasturtium enzyme also showed evidence of XET-xyloglucan complex-formation according to anion-exchange chromatography and adsorption of the complex to filter paper on the basis of affinity of its xyloglucan moiety for cellulose. The XET-xyloglucan complex was stable in water, 6 M urea and acidic and alkaline buffers (pH 2.5-9.5), but readily decomposed by transferring its glycosyl moiety to xyloglucan-derived oligosaccharides or by incubation with the strong nucleophile imidazole at pH 3.8-9.6. These results strongly support the assumption that XET forms a relatively stable covalently linked glycosyl-enzyme intermediate.

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