Molekulare und kinetische Charakterisierung der Xanthin-Dehydrogenase aus dem phototrophen Bakterium Rhodopseudomonas capsulata / Molecular and Kinetic Characterization of Xanthine Dehydrogenase from the Phototrophic Bacterium Rhodopseudomonas capsulata

1981 ◽  
Vol 36 (11-12) ◽  
pp. 933-941 ◽  
Author(s):  
Werner Aretz ◽  
Herwig Kaspari ◽  
Jobst-Heinrich Klemme
Keyword(s):  
Molecular Weight ◽  
Uric Acid ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Xanthine Dehydrogenase ◽  
Rhodopseudomonas Capsulata ◽  
Kinetic Properties ◽  
Effective Electron ◽  
Enzyme Preparations ◽  
Phototrophic Bacterium

Abstract The structural and kinetic properties of xanthine dehydrogenase (EC 1.2.1.37) from the facultative phototrophic bacterium Rhodopseudomonas capsulata were studied. The enzyme was fully induced when hypoxanthine or xanthine, but less effectively when uric acid served as nitrogen source during growth. The enzyme was purified about 2300-fold from cells grown photosynthetically with hypoxanthine as N-source by using ammoniumsulfate precipitation, gel filtration, ion-exchange and affinity chromatography. The molecular weight as determined by gel filtration throug Sephacryl S-300 was 345000. Subunit analysis by sodium dodecyl sulfate gel electrophoresis suggested a composition of four identical subunits with a molecular weight of 84000. The enzyme contained 2 flavin, 2 molybdenum and 8 iron-sulfur groups per mol. The turnover number with hypoxanthine and NAD as substrates was 12000 min-1. Hypoxanthine, 1-methylhypoxanthine, 8-azahypoxanthine, xanthine, 1-methylxanthine, 2-hydroxypurine, 6,8-di-hydroxypurine, 5-azacytosine and 5-azauracil served as electron donors. The most effective electron acceptor was NAD. The kinetic constants (Km) were (in μm): 52.5 (hypoxanthine); 32.5 (xanthine) and 61.2 (NAD). Various purine compounds inhibited the enzyme competitively in respect to hypoxanthine as substrate. Although reduction of uric acid to xanthine was not detected by using purified enzyme preparations, in vitro-experiments with 14C-labelled uric acid indicated that the enzyme xanthine dehydrogenase participates in uric acid degradation in Rps. capsulata. According to their electrophoretic mobilities, the xanthine dehydrogenases isolated from hypoxanthine-and uric acid-grown cells were identical.

scholarly journals Partial purification of topoisomerase IB from serum of diabetic patients and study it's kinetic properties and molecular weight

2019 ◽  
Vol 23 (10) ◽  
pp. 46
Author(s):  
Saif M. Hasan ◽  
Firas T. Maher ◽  
Nagham Q. Kadhim
Keyword(s):  
Molecular Weight ◽  
Specific Activity ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Maximum Velocity ◽  
Partial Purification ◽  
Diabetic Patients ◽  
Kinetic Properties ◽  
Topoisomerase Ib ◽  
Electrophoresis Method

This study was done to partially purification of  topoisomerase IB from serum of diabetic patients using Gel filtration technique, by using Sephadex G 100 gel. A single peak in fraction four has been obtained, and the degree of purification (17.1) fold, enzyme yield (108.2%) and specific activity (0.189ng/mg). Kinetics studies for the partial purified enzyme were carried out which showed optimal concentration of  substrate which was (0.1ng/ml), Michael's - Menten constant (Km=0.033ng) and maximum velocity (Vmax=0.90 ng/ml), while optimum Temperature was (37C°) and optimum pH was (7.5). The molecular weight of the partial purified enzyme has been determined by gel electrophoresis method, in presence of polyacrylamide  gel and sodium dodecyl sulphate (SDS-PAGE) which showed that the approximated molecular weight was (66KD).   http://dx.doi.org/10.25130/tjps.23.2018.168 

Partial purification of a boar sperm membrane protein inducing sperm agglutinating antibody

1990 ◽  
Vol 10 (2) ◽  
pp. 131-139
Author(s):  
Oyewole Adeyemo ◽  
E. O. Okegbile ◽  
O. O. Olorunsogo
Keyword(s):  
Molecular Weight ◽  
Membrane Protein ◽  
Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Partial Purification ◽  
Boar Sperm ◽  
Sperm Membrane ◽  
Triton X

For the development of immunological contraception, attention is being concentrated on the possibility of using a sperm membrane antigen. Boar sperm membrane was extracted with triton-X 100 and fractionated by Sephadex G-150 column chromatography. The glycosylated and nonglycosylated portions of protein peaks from the gel filtration were obtained by fractionating on concanavalin A-Sepharose and eluting the bound protein with 0.3 M methyl mannoside. A glycosylated fraction was found to induce sperm agglutinating antibodies in rabbit. The partially purified protein has a molecular weight of 30 kilodaltons, as determined by sodium dodecyl polyaccyrlamide gel electrophoresis. Further work is planned on the histochemical determination of the origin of this protein and species cross-activity of the antibody.

scholarly journals Effects of pronase and neuraminidase treatment on a myelin-associated glycoprotein in developing brain

1976 ◽  
Vol 156 (1) ◽  
pp. 143-150 ◽  
Author(s):  
R H Quarles
Keyword(s):  
Molecular Weight ◽  
Sialic Acid ◽  
Sodium Dodecyl Sulphate ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Apparent Molecular Weight ◽  
Weight Class ◽  
Developmental Difference ◽  
Adult Rats ◽  
Neuraminidase Treatment

Rats (14 days old) were injected with [14c]fucose and young adult rats with [3H]fucose in order to label the myelin-associated glycoproteins. As previously reported, the major [14C]fucose-labelled glycoprotein in the immature myelin had a higher apparent molecular weight on sodium dodecyl sulphate/polyacrylamide gels that the [3H]fucose-labelled glycoprotein in mature myelin. This predominant doubly labelled glycoprotein component was partially purified by preparative gel electrophoresis and converted to glycopeptides by extensive Pronase digestion. Gel filtration on Sephadex G-50 separated the glycopeptides into several clases, which were designted A,B, C AND D, from high to low molecular weight. The 14C-labelled glycopeptides from immature myeline were enriched in the highest-molecular-weight class A relative to the 3H-labelled glycopeptides from mature myelin. Neuraminidase treatment of the glycoprotein before Pronase digestion greatly decreased the proportion of glycopeptides fractionating in the higher-molecular-weight classes and largely eliminated the developmental differences that were apparent by gel filtration. However, neuraminidase treatment did not decrease the magnitude of the developmental difference revealed by electrophoresing the intact glycoprotein on sodium dodecyl sulphate gels, although it did decrease the apparent molecular weight of the glycoprotein from both the 15-day-old and adult rats by an amount comparable in magnitude to that developmental difference. The results from gel filtration of glycopeptides indicate that there is a higher content of large molecular weight, sialic acid-rich oligosaccharide units in the glycoprotein of immature myelin. However, the higher apparent molecular weight for the glycoprotein from 15-day-old rats on sodium dodcyl sulphate gels is not due primarily to its higher sialic acid content.

scholarly journals Isolation and Characterization of Two Proteins fromMoraxella catarrhalis That Bear a Common Epitope

1998 ◽  
Vol 66 (9) ◽  
pp. 4374-4381 ◽  
Author(s):  
John C. McMichael ◽  
Michael J. Fiske ◽  
Ross A. Fredenburg ◽  
Deb N. Chakravarti ◽  
Karl R. VanDerMeid ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Bacterial Attachment ◽  
Vaccine Candidates ◽  
Isolation And Characterization ◽  
Sds Page

ABSTRACT The UspA1 and UspA2 proteins of Moraxella catarrhalisare potential vaccine candidates for preventing disease caused by this organism. We have characterized both proteins and evaluated their vaccine potential using both in vitro and in vivo assays. Both proteins were purified from the O35E isolate by Triton X-100 extraction, followed by ion-exchange and hydroxyapatite chromatography. Analysis of the sequences of internal peptides, prepared by enzymatic and chemical cleavage of the proteins, revealed that UspA1 and UspA2 exhibited distinct structural differences but shared a common sequence including an epitope recognized by the monoclonal antibody 17C7. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), purified UspA1 exhibited a molecular weight of approximately 350,000 when unheated and a molecular weight of 100,000 after being heated for 10 min at 100°C. In contrast, purified UspA2 exhibited an apparent molecular weight of 240,000 by SDS-PAGE that did not change with the length of time of heating. Their sizes as determined by gel filtration were 1,150,000 and 830,000 for UspA1 and UspA2, respectively. Preliminary results indicate the proteins have separate functions in bacterial pathogenesis. Purified UspA1 was found to bind HEp-2 cells, and sera against UspA1, but not against UspA2, blocked binding of the O35E isolate to the HEp-2 cells. UspA1 also bound fibronectin and appears to have a role in bacterial attachment. Purified UspA2, however, did not bind fibronectin but had an affinity for vitronectin. Both proteins elicited bactericidal antibodies in mice to homologous and heterologous disease isolates. Finally, mice immunized with each of the proteins, followed by pulmonary challenge with either the homologous or a heterologous isolate, cleared the bacteria more rapidly than mock-immunized mice. These results suggest that UspA1 and UspA2 serve different virulence functions and that both are promising vaccine candidates.

scholarly journals Characterization of proteins from the cytoskeleton of Giardia lamblia

1983 ◽  
Vol 59 (1) ◽  
pp. 81-103 ◽  
Author(s):  
R. Crossley ◽  
D.V. Holberton
Keyword(s):  
Molecular Weight ◽  
Sodium Dodecyl Sulphate ◽  
Giardia Lamblia ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Molecular Size ◽  
Molecular Weights

Proteins from the axonemes and disc cytoskeleton of Giardia lamblia have been examined by sodium dodecyl sulphate/polyacrylamide gel electrophoresis. In addition to tubulin and the 30 X 10(3) molecular weight disc protein, at least 18 minor components copurify with the two major proteins in Triton-insoluble structures. The most prominent minor bands have the apparent molecular weights of 110 X 10(3), 95 X 10(3) and 81 X 10(3). Protein of 30 X 10(3) molecular weight accounts for about 20% of organelle protein on gels. In continuous 25 mM-Tris-glycine buffer it migrates mostly as a close-spaced doublet of polypeptides, which are here given the name giardins. Giardia tubulin and giardin have been purified by gel filtration chromatography in the presence of sodium dodecyl sulphate. Well-separated fractions were obtained that could be further characterized. Both proteins are heterogeneous when examined by isoelectric focusing. Five tubulin chains were detected by PAGE Blue 83 dye-binding after focusing in a broad-range ampholyte gel. Giardin is slightly less acidic than tubulin. On gels it splits into four major and four minor chains with isoelectric points in the pI range from 5.8 to 6.2. The amino acid composition of the giardin fraction has been determined, and compared to Giardia tubulin and a rat brain tubulin standard. Giardins are rich in helix-forming residues, particularly leucine. They have a low content of proline and glycine; therefore they may have extensive alpha-helical regions and be rod-shaped. As integral proteins of disc microribbons, giardins in vivo associate closely with tubulin. The properties of giardins indicate that in a number of respects - molecular size, charge, stoichiometry - their structural interaction with tubulin assemblies will be different from other tubulin-accessory protein copolymers studied in vitro.

scholarly journals Separation and partial characterization of guinea-pig caseins

1978 ◽  
Vol 173 (2) ◽  
pp. 633-641 ◽  
Author(s):  
R K Craig ◽  
D McIlreavy ◽  
R L Hall
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Guinea Pig ◽  
Amino Acid Composition ◽  
Acid Composition ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Exchange Chromatography

1. Guinea-pig caseins A, B and C were purified free of each other by a combination of ion-exchange chromatography and gel filtration. 2. Determination of the amino acid composition showed all three caseins to contain a high proportion of proline and glutamic acid, but no cysteine. This apart, the amino acid composition of the three caseins was markedly different, though calculated divergence values suggest that some homology may exist between caseins A and B. Molecular-weight estimates based on amino acid composition were in good agreement with those based on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. 3. N-Terminal analysis showed lysine, methionine and lysine to be the N-terminal residues of caseins A, B and C respectively. 4. Two-dimensional separation of tryptic digests revealed a distinctive pattern for each casein. 5. All caseins were shown to be phosphoproteins. The casein C preparation also contained significant amounts of sialic acid, neutral and amino sugars. 6. The results suggest that each casein represents a separate gene product, and that the low-molecular-weight proteins are not the result of a post-translational cleavage of the largest. All were distinctly different from the whey protein alpha-lactalbumin.

scholarly journals Molecular weight and subunit size of fatty acid synthetase from rabbit mammary gland

1976 ◽  
Vol 159 (1) ◽  
pp. 181-184 ◽  
Author(s):  
N Paskin ◽  
R J Mayer
Keyword(s):  
Molecular Weight ◽  
Mammary Gland ◽  
Fatty Acid ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Fatty Acid Synthetase ◽  
Subunit Size

Fatty acid synthetase purified from the mammary gland of the rabbit has a mol. wt. of 968000 as determined by gel filtration. The enzyme gave one band, corresponding to a mol.wt. of approx. 35000, on polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate and phenylmethanesulphonyl fluoride.

Purification and studies of some physicochemical properties of glutamine synthetase of Neurospora crassa

1978 ◽  
Vol 56 (10) ◽  
pp. 927-933 ◽  
Author(s):  
W. S. Lin ◽  
M. Kapoor
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Glutamine Synthetase ◽  
Neurospora Crassa ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Sedimentation Coefficient ◽  
Affinity Column ◽  
Subunit Structure ◽  
Α Helix

Glutamine synthetase (EC 6.3.1.2) of Neurospora crassa was purified to near homogeneity by chromatography on a glutamate–Sepharose affinity column. Its properties, including molecular weight, subunit structure, amino acid composition, and approximate α-helix content, have been examined. In the native state, this enzyme has been demonstrated by gel filtration to be an octamer of molecular weight 360 000 and as having a sedimentation coefficient of 13.2 S by sedimentation velocity measurements. Circular dichroism spectra in the far ultraviolet range suggest an approximate α-helix content of 23–24%. The subunit generated by treatment with urea was found to be 45 000 daltons by gel filtration methods and a molecular weight of 46 000 was calculated for the monomer obtained by sodium dodecyl sulphate (SDS) treatment and electrophoresis in SDS-polyacrylamide gels. Interprotomeric cross-linking experiments, using diimidoesters, suggest the presence of two noncovalently linked tetramers comprising the native octameric structure. Amino acid analyses revealed the presence of six tryptophans, four half cystines, and nine methionine residues per monomer of 45 000 daltons.

scholarly journals Purification and some properties of rabbit antiovalbumin

1973 ◽  
Vol 135 (4) ◽  
pp. 705-711 ◽  
Author(s):  
Aftab A. Ansari ◽  
A. Salahuddin
Keyword(s):  
Molecular Weight ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Acid Media ◽  
Stokes Radius ◽  
Antigen Antibody ◽  
Two Peaks ◽  
Complete Dissociation ◽  
Phosphate Groups

Unlike previous reports that the ovalbumin–anti-ovalbumin complex did not dissociate completely in acid media, our results showed complete dissociation of the complex both in 1.2m-acetic acid, pH2.3, and in KCl–HCl, pH2.2, I 0.06. Thus Sephadex chromatography of the solution obtained by dissolving the antigen–antibody precipitate in these media repeatedly gave two peaks corresponding to anti-ovalbumin and ovalbumin. Further, gel-diffusion and immunoelectrophoresis experiments showed that the phosphate groups of ovalbumin are not involved in the antigenic sites. The antibody thus purified was more easily precipitated than previous preparations. The molecular weight and Stokes radius of the antibody were calculated from its gel-filtration behaviour and were found to be 148000 and 4.8nm respectively. The molecular weight determined by sodium dodecyl sulphate–polyacrylamide gel electrophoresis was essentially similar (about 0.7% lower).

scholarly journals Rabbit Tamm–Horsfall urinary glycoprotein. Chemical composition and subunit structure

1971 ◽  
Vol 122 (5) ◽  
pp. 623-631 ◽  
Author(s):  
Anne M. S. Marr ◽  
A. Neuberger ◽  
Wendy A. Ratcliffe
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Chemical Composition ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Subunit Structure ◽  
Terminal Amino

1. Tamm–Horsfall glycoprotein from rabbit urine has been isolated and characterized. The homogeneity of the preparation has been established by a variety of procedures including disc gel electrophoresis and ultracentrifugation in aqueous solution, sodium dodecyl sulphate and formic acid. 2. The chemical composition has been determined and a carbohydrate content of approx. 31% was obtained. The relative contents of the amino acids were shown to be very similar to those in human Tamm–Horsfall glycoprotein. A trace of lipid was also detected. 3. Leucine was identified as the only N-terminal amino acid. 4. The subunit structure was investigated in the presence of sodium dodecyl sulphate by gel filtration and disc gel electrophoresis. These studies indicated that the subunit possessed a molecular weight of approx. 84000±6000. A similar value was obtained after reduction and S-alkylation of the glycoprotein indicating that the disulphide bonds were all intrachain. 5. A minimum value for the chemical molecular weight of 85000±6000 was obtained from the number of N-terminal amino acids released by cyanogen bromide cleavage of the glycoprotein. 6. The immunological properties of the glycoprotein were studied. Cross reactivity was demonstrated between human Tamm–Horsfall glycoprotein and a guinea-pig anti-rabbit Tamm–Horsfall antiserum.

Sign in / Sign up

Export Citation Format

Share Document