Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.1.27.4 (ribonuclease)
6,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A method using p-benzoquinone for coupling antigens and antibodies to enzymes and erythrocytes is described. The method involves the treatment of proteins (or polysaccharides) at pH 6 or 7 with an excess of p-benzoquinone. After removal of the unreacted reagent by gel filtration, the "activated" proteins were coupled at pH 8-9 with enzymes or erythrocytes. Biological activities of the proteins were not substantially modified by this treatment since 80-100% of the antigen binding capacity was found to be preserved in p-benzoquinone treated antibodies or Fab fragments. Anti-Ig antibodies (or Fab) were coupled by this procedure to peroxidase, alkaline phosphatase, lactoperoxidase, glucose oxidase and beta-galactosidase, and the conjugates obtained were found to be highly effective in detecting intracellular Ig by immunohistochemical techniques. Erythrocytes coated with sheep anti-mouse Ig antibody or Fab were used to titrate by passive hemagglutination serum Ig. The same erythrocytes were employed to detect by plaque assay mouse Ig secreting cells. Erythrocytes coated with peroxidase, alkaline phosphatase, bovine serum albumin, ribonuclease, Salmonella polysaccharide (B 27 +) and pneumoccocal polysaccharide SIII were employed to titrate serum antibody by passive hemagglutination and hemolysis and to detect mouse antibody secreting cells by plaque assay. All the antigens and antibodies coated erythrocytes prepared gave highly satisfactory and reproducible results.
...
PMID:A new method using p-benzoquinone for coupling antigens and antibodies to marker substances. 0 79

Three types of immunoadsorbents were synthetized by antigen coupling to glutaraldehyde-activated polyacrylamide gel, BrCN-activated sepharose 4B and protein insolubilization using glutaraldehyde as a cross-linking agent. Different concentrations of rabbit gamma globulin, bovine serum albumin, soybean trypsin inhibitor and bovine ribonuclease were used as antigens and some properties of such immunoadsorbents were studied. Using 125J labelled antigens it was shown that glutaraldehyde-activated polyacrylamide gel (Bio-Gel P-300) couples 81-94% of the antigen added in a concentration of 0.5-4.0 mg.ml-1 gel and BrCN-activated sepharose 4B bounds 62-88% of the labelled antigen in a concentration of 5.0-20.0 mg.ml-1 gel. These antigen derivatives as well as those obtained by glutaraldehyde protein insolubilization permitted 54-88% of antibodies added with the immune sera to be isolated. There was a significant antigen leakage from sepharose immunoadsorbents after several antisera treatments or after half a year storage but despite of this antigen desorption all types of the immunoadsorbents studied preserved their antibody isolation capacity. Immune sera immunoglobulins nonspecific binding by immunoadsorbents was less on sepharose than Bio-Gel antigen derivatives.
...
PMID:[Properties of immunoadsorbents prepared by antigen coupling to glutaraldehydeactivated polyacrylamide gel, BrCN-activated Sepharose and by copolymerization of antigens by glutaraldehyde]. 9 83

Serum alkaline ribonuclease activity and serum albumin concentration were determined in 25 normal children and 59 children with protein-energy malnutrition. The increase in serum ribonuclease was marked in marasmus and marasmic kwashiorkor. The ribonuclease activity dropped significantly after two weeks of treatment and returned to normal by four weeks. In kwashiorkor, serum ribonuclease activity was significantly lower than control and returned to normal after four weeks of treatment. These findings support previous observations that the serum ribonuclease is a good criterion of the nutritional status and indicates that the enzyme activity, particularly when related to serum albumin, is a good prognostic index in this respect.
...
PMID:The activity of serum ribonuclease in protein-energy malnutrition. 10 57

The protein spin-echo decay and recovery of longitudinal magnetization were studied in seven globular proteins: cytochrome C, ribonuclease, lysozyme, DNA, hemoglobin, serum albumin and gamma-globulin in D2O solutions. For comparison the Tobacco mosaic virus (TMV) protons in D2O solutions were also investigated. The spin-echo decay of all 7 proteins can be separated into three components: a slowly decaying component with an amplitude of about 10% of the amplitude of the total signal, intermediately and fastly decaying components, the two latter being comparable in amplitudes. Longitudinal relaxation is more simple in character. The value of T2 of the protons responsible for the fastly decaying components in linearly dependent on the molecular weight of the protein, a fact indicating that the regions of the proteins with a "rigid" structure can be responsible for this component. The intermediate component, whose contribution increases with temperature, was ascribed to the mobile regions of the protein, and the slowly decaying component to the mobile protein side chains. Weak dependence of T1 on the protein molecular weight and some other obtained data give additional evidence for the presence of motion within macromolecules. The peculiarities of this motion is in good correspondence with the notion about the existence of the segmental motion of the polypeptide chain (conformational mobility of the protein). In contrast to proteins the spin-echo decay of TMV lacked the slow component and the "solid" echo signal was observed which indicates the existence of a "rigid" structure in the macromolecules of the virus.
...
PMID:[Study of the conformational mobility of globular proteins by pulse methods of NMR]. 20 75

Heat-stable enterotoxin (ST) produced by porcine strains of enterotoxigenic (ENT+) Escherichia coli has been purified to apparent homogeneity by sequential ultrafiltration, acetone fractionation, preparative gel electrophoresis, diethylaminoethyl Bio-Gel A ion-exchange chromatography, and Bio-Gel P-10 gel filtration. The enterotoxin, purified more than 1,500-fold, exhibited a molecular weight of 4,400, as determined by both sodium dodecyl sulfate-gel electrophoresis and gel filtration. A molecular weight of 5,100, representing 47 residues, was calculated from amino acid analysis data. The amino acid content was distinctive, with an unusually high proportion of cystines and few hydrophobic amino acids. A single amino-terminal residue, glycine, was observed. Purified ST was stable to heating (100 degrees C, 30 min) and did not lose biological activity after treatment with Pronase, trypsin, proteinase K, deoxyribonuclease, ribonuclease, and phospholipase C. Periodic acid oxidation and several organic solvents (acetone, phenol, chloroform, and methanol) had no effect on the biological activity of ST. Further, purified ST was stable to acid treatment at pH 1.0 but lost biological activity at pH values greater than 9.0. Neither lipopolysaccharide nor lipid contamination was evident in purified preparations. A characteristic absorption spectrum was observed during the course of the purification, which shifted from a maximum at 260 nm in crude preparations to 270 nm for the purified toxin. Antiserum obtained from rabbits immunized with ST or ST coupled to bovine serum albumin neutralized the action of the enterotoxin in suckling mice; however, passive hemagglutination and hemolysis titer assays suggested that ST is a poor antigen.
...
PMID:Purification and chemical characterization of the heat-stable enterotoxin produced by porcine strains of enterotoxigenic Escherichia coli. 34 81

The second derivative absorption spectra of serum albumin, insulin, ribonuclease and lysozyme were measured under various conditions to determine the state and amount of their phenylalanine residues. The second derivative spectra of these proteins were very similar to that of phenylalanine in the region between 245 and 270 nm where tryptophan and tyrosine residues caused no appreciable interference. Denaturation of proteins with urea or guanidine hydrochloride caused decrease in the intensity of the second derivative spectra, but scarcely affected the positions of peaks and troughs. The amounts of phenylalanine residues in proteins calculated from a second derivative spectra of denatured proteins coincided well with those reported in the literature. The states of the phenylalanine residues in the proteins could be deduced from the change in optical intensity on denaturation.
...
PMID:Estimation of state and amount of phenylalanine residues in proteins by second derivative spectrophotometry. 39 35

An inert polymer pellet less than 1 mm in diameter, implanted subcutaneously in mice, releases free antigen continuously and enhances antibody formation for over 6 months. The immune response stimulated by sustained antigen delivery is comparable to the secondary response induced by the same total dose of antigen emulsified in complete Freund's adjuvant. The sustained release polymer implants, using antigens over a wide molecular weight range, proved effective in eliciting prolonged antibody formation. The antigens tested included bovine serum albumin, gamma-globulin, and ribonuclease. Superior biocompatibility and release characteristics make the ethylene-vinyl acetate copolymer a promising method for the single-step induction of immunity.
...
PMID:A single-step immunization by sustained antigen release. 46 67

The binding isotherms of native bovine serum albumin with cationic detergents, such as octyl, decyl, dodecyl and tetradecylpyridinium bromides were determined at pH 6.8 and 3.4 at 25 degrees C. The isotherms for dodecyl and tetradecylpyridinium bromides were also determined at 3 degrees C. The average number of detergent cations bound increased with increasing hydrocarbon chain length. At low detergent concentration the binding of all alkylpyridinium bromides was smaller at pH 3.4 than at pH 6.8. Dodecylpyridinium bromide was bound to native beta-lactoglobulin, aldolase, ovalbumin, haemoglobin, myoglobin, lysozyme, trypsin and ribonuclease at pH 6.8. No binding occurred to alpha-chymotrypsin and chymotrypsinogen. The free enthalpy change, --delta G degrees, calculated from intrinsic association constants K was determined.
...
PMID:Protein-cationic detergent interaction. Equilibrium dialysis study of the interaction of bovine serum albumin and other proteins with alkylpyridinium bromide. 49 43

Fourier transform infrared and laser Raman spectroscopies were used to study the effects of dodecylpyridinium bromide on the conformation of haemoglobin, myoglobin, bovine serum albumin, ribonuclease, ovalbumin, lysozyme, trypsin and beta-lactoglobulin in aqueous solution. Addition of the cationic detergent caused a decrease in alpha-helix conformation in highly helical proteins. At low detergent concentrations stabilization of beta-sheet conformation was observed.
...
PMID:Protein-cationic detergent interaction. Fourier transform infrared and laser Raman spectroscopic studies on the interaction between proteins and dodecylpyridinium bromide. 49 44

The quantity and activities of membrane-bound and free polysomes in livers from chick embryos at successive stages of development were compared in cell-free protein-synthesizing systems. Membrane-bound polysomes increased 2-fold between 8 and 18 days of development, while total ribosome content remained constant. Free polysome activity also remained constant during this period, while that of membrane-bound (total--free) polysomes decreased, possibly because of an increase in ribonuclease activity in this fraction. Serum albumin biosynthesis occurred primarily on membrane-bound polysomes. With liver development, increased secretion of serum proteins may be correlated with synthesis of serum albumin on increasing numbers of membrane bound polyribosomes.
...
PMID:Polymorphism in fowl serum albumin. VII. Distribution and activity of free and membrane-bound polysomes in developing fowl liver. 56 16


1 2 3 4 5 6 7 8 9 10 Next >>

---