Affinity chromatography study of the interaction of ribonucleotides with bovine pancreatic ribonuclease covalently bound to sepharose 4B

1983 ◽  
Vol 268 ◽  
pp. 255-264 ◽  
Author(s):  
M. Victòria Nogués ◽  
Alícia Guasch ◽  
Juli Alonso ◽  
Claudi M. Cuchillo
1985 ◽  
Vol 54 (02) ◽  
pp. 533-538 ◽  
Author(s):  
Wilfried Thiel ◽  
Ulrich Delvos ◽  
Gert Müller-Berghaus

SummaryA quantitative determination of soluble fibrin in plasma was carried out by affinity chromatography. For this purpose, desAA-fibrin and fibrinogen immobilized on Sepharose 4B were used at the stationary side whereas batroxobin-induced 125I-desAA-fibrin or thrombin-induced 125I-desAABB-fibrin mixed with plasma containing 131I-fibrinogen represented the fluid phase. The binding characteristics of these mixtures to the immobilized proteins were compared at 20° C and 37° C. Complete binding of both types of fibrin to the immobilized desAA-fibrin was always seen at 20° C as well as at 37° C. However, binding of soluble fibrin was accompanied by substantial binding of fibrinogen that was more pronounced at 20° C. Striking differences depending on the temperature at which the affinity chromatography was carried out, were documented for the fibrinogen-fibrin interaction. At 20° C more than 90% of the applied desAA-fibrin was bound to the immobilized fibrinogen whereas at 37° C only a mean of 17% were retained at the fibrinogen-Sepharose column. An opposite finding with regard to the tested temperature was made with the desAABB-fibrin. Nearly complete binding to insolubilized fibrinogen was found at 37° C (95%) but only 58% of the desAABB-fibrin were bound at 20° C. The binding patterns did not change when the experiments were performed in the presence of calcium ions. The opposite behaviour of the two types of soluble fibrin to immobilized fibrinogen at the different temperatures, together with the substantial binding of fibrinogen in the presence of soluble fibrin to insolubilized fibrin in every setting tested, devaluates affinity chromatography as a tool in the quantitative assessment of soluble fibrin in patients’ plasma.


1979 ◽  
Vol 57 (7) ◽  
pp. 986-994 ◽  
Author(s):  
Satish K. Sharma ◽  
Stewart A. Brown

Two discrete furanocoumarin (5- and 8-) O-methyltransferases and a caffeic acid 3-O-methyl-transferase from cell cultures of Ruta graveolens L. have been copurified by affinity chromatography on 1,6-diaminohexane agarose (AH-Sepharose 4B) linked with 5-adenosyl-L-homocysteine (SAH). The furanocoumarin O-methyltransferases, which transfer a methyl group from S-adenosyl-L-methionine (SAM) to the 5- or 8-hydroxyls of linear furanocoumarins, were not retarded by 5-(3-carboxypropanamido)-xanthotoxin (CPAX) immobilized to AH-Sepharose 4B, but addition of SAM to the irrigant buffer led to complete retardation of both enzymes on this affinity system. An analogous phenomenon was observed for the caffeic acid O-methyltransferase, with a ferulic acid ligand coupled to the same insoluble support. SAH was as effective as SAM in promoting binding of the furanocoumarin O-methyltransferases to CPAX and caffeic acid 3-O-methyltransferase to immobilized ferulic acid, respectively. The strong and specific adsorption of these enzymes was abolished by exclusion of SAM or SAH from the irrigant buffer. It is concluded that the enzymes bind first to SAM or SAH, and that this binding process in turn induces the binding site for their specific phenolic substrates or their analogs. Based on these findings, a compulsory–ordered kinetic mechanism for the action of these O-methyltransferases is postulated.


1977 ◽  
Vol 165 (1) ◽  
pp. 121-126 ◽  
Author(s):  
G D Smith ◽  
D V Roberts ◽  
A Daday

Several derivatives of phenylalanine and tyrosine were prepared and tested for inhibition of chorismate mutase-prephenate dehydrogenase (EC 1.3.1.12) from Escherichia coli K12 (strain JP 232). The best inhibitors were N-toluene-p-sulphonyl-L-phenylalanine, N-benzenesulphonyl-L-phenylalanine and N-benzloxycarbonyl-L-phenylalanine. Consequently two compounds, N-toluene-sulphonyl-L-p-aminophenylalanine and N-p-aminobenzenesulphonyl-L-phenylalanine, were synthesized for coupling to CNBr-activated Sepharose-4B. The N-toluene-p-sulphonyl-L-p-aminophenylalanine-Sepharose-4B conjugate was shown to bind the enzyme very strongly at pH 7.5. The enzyme was not eluted by various eluents, including 1 M-NaCl, but could be quantitatively recovered by washing with buffer of pH9. Elution was more effective in the presence of 10 mM-1-adamantaneacetic acid, a competitive inhibitor of the enzyme. This affinity-chromatography procedure results in a high degree of purification of the enzyme and can be used to prepare the enzyme in a one-step procedure from the bacterial crude extract. Such a procedure may therefore prove useful in studying this enzyme in a state that closely resembles that in vivo.


1986 ◽  
Vol 235 (3) ◽  
pp. 731-734 ◽  
Author(s):  
D H Rich ◽  
M A Brown ◽  
A J Barrett

Human cathepsin B was purified by affinity chromatography on the semicarbazone of Gly-Phe-glycinal linked to Sepharose 4B, with elution by 2,2′-dipyridyl disulphide at pH 4.0. The product obtained in high yield by the single step from crude starting material was 80-100% active cathepsin B. The possibility that this new form of affinity chromatography may be of general usefulness in the purification of cysteine proteinases is discussed.


1986 ◽  
Vol 32 (11) ◽  
pp. 2083-2084 ◽  
Author(s):  
P K Buamah ◽  
R Harris ◽  
O F James ◽  
A W Skillen

Abstract Affinity chromatography of serum on lentil lectin bound to Sepharose 4B has been used to identify different forms of alpha-fetoprotein in serum of patients with liver disease. We studied eight patients with non-malignant liver disease, finding that 7-15% of the serum alpha-fetoprotein bound to the lectin. In contrast, for 15 patients with malignant liver disease, 25-83% of the serum alpha-fetoprotein bound to the lectin. Evidently, this simple technique can be used effectively to differentiate these two conditions.


1981 ◽  
Author(s):  
R Wallin ◽  
M Belew ◽  
K Ohlsson ◽  
T Saldeen

The presence of leucocytes around extravascular fibrin deposits suggests that the leucocyte elastases might be partly responsible for the extravascular degradation of fibrin. Our previous studies have shown that the degradation of fibrin(ogen) by plasmin leads to the release of 2 small peptides which markedly increase vascular permeability and induce oedema e.g. in the lungs. The results of this investigation show that small peptides released from fibrinogen after degradation by leucocytes elastases also increase vascular permeability.Human fibrinogen (Kabi, Grade L) was made plasminogenfree by affinity chromatography on Lysine-Sepharose 4B prior to use. The human leucocyte elastases were isolated from extracts of lysosome-like granules of human leukaemic myeloid cells by a combination of gel filtration, affinity chromatography and preparative agarose gel electrophoresis. The fibrinogen (0.5 %) and the leucocyte elastases (in a molar ratio of 100:1) were incubated together for 48 h at +37°C and at pH 8.5. The mixture was then cooled to +4°C to stop the lysis and ultrafiltrated on a DIAFLO PM 10 membrane until the retentate was approximately 10 % of the starting volume. The peptides in the diffusate accounted for about 20 % of the starting material as estimated from absorbance measurements at 280 nm. The diffusate was concentrated by lyophilization and fractionated by chromatography on a column of Bio-Gel P-6. At least 8 fractions were obtained of which only two showed a significant activity in their ability to increase vascular permeability in rat skin. The active peptides in these two fractions were further purified to homogeneity by column zone electrophoresis at various pHs and their amino acid compositions established.


1978 ◽  
Vol 83 (3) ◽  
pp. 1198-1205 ◽  
Author(s):  
Michael J. Griffith ◽  
Henry S. Kingdon ◽  
Roger L. Lundblad

1994 ◽  
Vol 304 (1) ◽  
pp. 301-305 ◽  
Author(s):  
M E Monaco ◽  
M Feldman ◽  
D L Kleinberg

Substantial purification of rat liver phosphatidylinositol (PtdIns) synthase has been achieved by a combination of Hecameg extraction, heat treatment, affinity chromatography and chromatography on PBE-94. The activity chromatographs as a single peak which has an apparent molecular mass between 150 and 200 kDa on Sepharose 4B. When analysed by SDS/PAGE, two major bands are seen. The enzyme activity is correlated with a protein band of 21 kDa. A second band, at 51 kDa, is eluted from a PBE-94 column slightly ahead of the activity. Manganese is an absolute requirement for stabilization of activity in the presence of detergent. The effect of manganese is optimal at 0.5 mM; magnesium at a concentration of 10 mM is only minimally effective. Substrate Kms are 1.3 mM and 9.5 microM for inositol and CDP-diacylglycerol respectively. The activity eluting from the PBE-94 column is purified 5000-fold over the post-mitochondrial supernatant.


1987 ◽  
Vol 33 (8) ◽  
pp. 1478-1483 ◽  
Author(s):  
K Fujita ◽  
I Sakurabayashi ◽  
M Kusanagi ◽  
T Kawai

Abstract The serum of a patient with IgG1-lambda type M-proteinemia showed an abnormal isoenzyme pattern for lactate dehydrogenase (LDH, EC 1.1.1.27). By affinity chromatography, we showed that four isoenzymes (LDH2, LDH3, LDH4, and LDH5) were bound to the M-protein. This complex formation was not blocked by anti-idiotype antibody, even though the binding capacity of IgG was exclusively located in the Fab region of the molecule. Moreover, heavy and light chains of the patient's IgG, obtained by reduction, separately had affinities for each of the LDH isoenzymes. LDH-IgG complex was easily dissociated by affinity chromatography on 5'-AMP-Sepharose 4B or by added NADH. We propose the following hypothesis for the LDH-IgG complex formation: LDH can recognize the gamma-Fab region of IgG at the NAD+ binding site of the molecule, but the affinity of the LDH molecule for immunoglobulin is much weaker than that for NADH or 5'-AMP.


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