Isolation and characterization of dihydropteridine reductase from human liver

Dihydropteridine reductase (EC 1.6.99.7) was purified from human liver obtained at autopsy by a three-step chromatographic procedure with the use of (1) a naphthoquinone affinity adsorbent, (2) DEAE-Sephadex and (3) CM-Sephadex. The enzyme was typically purified 1000-fold with a yield of 25%. It gave a single band on non-denaturing and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, and showed one spot on two-dimensional gel electrophoresis. The molecular weight of the enzyme was determined to be 50000 by sedimentation-equilibrium analysis and 47500 by gel filtration. On sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, a single subunit with mol.wt. 26000 was observed. A complex of dihydropteridine reductase with NADH was observed on gel electrophoresis. The isoelectric point of the enzyme was estimated to be pH 7.0. Amino acid analysis showed a residue composition similar to that seen for the sheep and bovine liver enzymes. The enzyme showed anomalous migration in polyacrylamide-gel electrophoresis. A Ferguson plot indicated that this behaviour is due to a low net charge/size ratio of the enzyme under the electrophoretic conditions used. The kinetic properties of the enzyme with tetrahydrobiopterin, 2-amino-4-hydroxy-6,7-dimethyl-5,6,7,8-tetrahydropteridine, NADH and NADPH are compared, and the effects of pH, temperature and a number of different compounds on catalytic activity are presented.

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Identification of a basic hybrid glutathione S-transferase from human liver. Glutathione S-transferase δ is composed of two distinct subunits (B1 and B2)

Biochemical Journal ◽

10.1042/bj2270457 ◽

1985 ◽

Vol 227 (2) ◽

pp. 457-465 ◽

Cited By ~ 53

Author(s):

P K Stockman ◽

G J Beckett ◽

J D Hayes

Keyword(s):

Isoelectric Point ◽

Sodium Dodecyl Sulphate ◽

Gel Electrophoresis ◽

Human Liver ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Polyacrylamide Gel ◽

Glutathione S Transferase ◽

Liver Glutathione ◽

Glutathione S Transferases

The purification of a hybrid glutathione S-transferase (B1 B2) from human liver is described. This enzyme has an isoelectric point of 8.75 and the B1 and B2 subunits are distinguishable immunologically and are ionically distinct. Hybridization experiments demonstrated that B1 B1 and B2 B2 could be resolved by CM-cellulose chromatography and have pI values of 8.9 and 8.4 respectively. Transferase B1 B2, and the two homodimers from which it is formed, are electrophoretically and immunochemically distinct from the neutral enzyme (transferase mu) and two acidic enzymes (transferases rho and lambda). Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis demonstrated that B1 and B2 both have an Mr of 26 000, whereas, in contrast, transferase mu comprises subunits of Mr 27 000 and transferases rho and lambda both comprise subunits of Mr 24 500. Antisera raised against B1 or B2 monomers did not cross-react with the neutral or acidic glutathione S-transferases. The identity of transferase B1 B2 with glutathione S-transferase delta prepared by the method of Kamisaka, Habig, Ketley, Arias & Jakoby [(1975) Eur. J. Biochem. 60, 153-161] has been demonstrated, as well as its relationship to other previously described transferases.

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Detection of metalloproteins in human liver cytosol by synchrotron radiation X-ray fluorescence after sodium dodecyl sulphate polyacrylamide gel electrophoresis

Analytica Chimica Acta ◽

10.1016/s0003-2670(03)00347-7 ◽

2003 ◽

Vol 485 (1) ◽

pp. 131-137 ◽

Cited By ~ 32

Author(s):

Yuxi Gao ◽

Chunying Chen ◽

Peiqun Zhang ◽

Zhifang Chai ◽

Wei He ◽

...

Keyword(s):

Synchrotron Radiation ◽

Sodium Dodecyl Sulphate ◽

Gel Electrophoresis ◽

Human Liver ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Polyacrylamide Gel ◽

Liver Cytosol ◽

X Ray

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Affinity purification and some molecular properties of human liver alkaline phosphatase

Biochemical Journal ◽

10.1042/bj1550653 ◽

1976 ◽

Vol 155 (3) ◽

pp. 653-660 ◽

Cited By ~ 68

Author(s):

J M Trépanier ◽

L E Seargeant ◽

R A Stinson

Keyword(s):

Alkaline Phosphatase ◽

Sodium Dodecyl Sulphate ◽

Gel Electrophoresis ◽

Human Liver ◽

Affinity Purification ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Deae Cellulose ◽

Polyacrylamide Gel ◽

Neuraminidase Treatment

Alkaline phosphatase from human liver was purified to homogeneity. The purification procedure included solubilization with butanol, fractionation with acetone, and chromatography on concanavalin A-Sepharose, DEAE-cellulose, Sephadex G-200 and DEAE-Sephadex. Purity was established by standard and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. The isoelectric point of the protein was determined to be 4.0. Sephadex-gel filtration gave a mol.wt. of 146000, although a higher value was obtained in the presence of 100mM-NaC1. The subunit mol.wt. 76700, was determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Neuraminidase treatment resulted in two enzyme-activity bands on isoelectric-focused gels with isoelectric points of 6.6 and 6.8. The desialylated enzyme gave only one protein band on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis with a subunit molecular weight indistinguishable from that of the non-neuraminidase-treated protein. The desialylated enzyme was more readily denatured by sodium dodecyl sulphate in the presence of mercaptoethanol than was the native enzyme.

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Identifikasi Daging Tikus Pada Produk Baso Dengan Metode Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE)

YARSI Medical Journal ◽

10.33476/jky.v26i2.394 ◽

2018 ◽

Vol 26 (2) ◽

pp. 058

Author(s):

Anna P. Roswiem ◽

Triayu Septiani

Keyword(s):

Sodium Dodecyl Sulphate ◽

Gel Electrophoresis ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Polyacrylamide Gel ◽

Sds Page

Bahan baku untuk membuat baso adalah daging hewan, pada umumnya dari daging sapi, ayam, ikan dan babi. Di beberapa daerah di Indonesia terjadi kasus baso tikus. Tujuan penelitian ini adalah menguji ada tidaknya kandungan daging tikus pada produk baso yang dijual di pasar Cempaka Putih-Kecamatan Kramat Jakarta Pusat dan di pedagang baso atau mie baso di sekitar kampus Universitas YARSI Jakarta. Daging adalah protein salah satu metode untuk mengidentifikasi protein adalah metode Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE). Hasil penelitian menunjukkan bahwa dari 6 sampel baso terindikasi ada 2 sampel baso dengan nomor 1 dan 5 yang dibuat dari campuran daging sapi dan tikus; ada 1 sampel baso dengan nomor 6 yang terbuat dari daging tikus; dan 2 sampel baso dengan nomor 2 dan 3 yang terbuat dari campuran sapi dan babi, dan hanya 1 sampel baso dengan nomor sampel 4 yang benar-benar terbuat dari daging sapi.

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Structural properties of homogeneous protein disulphide-isomerase from bovine liver purified by a rapid high-yielding procedure

Biochemical Journal ◽

10.1042/bj2130225 ◽

1983 ◽

Vol 213 (1) ◽

pp. 225-234 ◽

Cited By ~ 107

Author(s):

N Lambert ◽

R B Freedman

Keyword(s):

Amino Acid ◽

Sodium Dodecyl Sulphate ◽

Gel Electrophoresis ◽

Specific Activity ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Sedimentation Coefficient ◽

Bovine Liver ◽

Polyacrylamide Gel ◽

Protein Disulphide Isomerase

Protein disulphide-isomerase from bovine liver was purified to homogeneity as judged by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, two-dimensional electrophoresis and N-terminal amino acid analysis. The preparative procedure, a modification of that of Carmichael, Morin & Dixon [(1977) J. Biol. Chem. 252, 7163-7167], is much faster and higher-yielding than previous procedures, and the final purified material is of higher specific activity. The enzyme has Mr 57 000 as determined by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, both in the presence and in the absence of thiol compounds. Gel-filtration studies on Sephadex G-200 indicate an Mr of 107 000, suggesting that the native enzyme is a homodimer with no interchain disulphide bonds. Ultracentrifugation studies give a sedimentation coefficient of 3.5S, implying that the enzyme sediments as the monomer. The isoelectric point, in the presence of 8 M-urea, is 4.2, and some microheterogeneity is detectable. The amino acid composition is comparable with previous analyses of this enzyme from bovine liver and of other preparations of thiol:protein disulphide oxidoreductases whose relation to protein disulphide-isomerase has been controversial. The enzyme contains a very high proportion of Glx + Asx residues (27%). The N-terminal residue is His. The pure enzyme has a very small carbohydrate content, determined as 0.5-1.0% by the phenol/H2SO4 assay. Unless specific steps are taken to remove it, the purified enzyme contains a small amount (5 mol/mol of enzyme) of Triton X-100 carried through the purification.

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