Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.26.9 (ribonuclease)
 6,589 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The amino acid sequences of the pancreatic ribonucleases from river-breed water buffaloes from Italy and swamp-breed water buffaloes from Indonesia differ at three positions. One of the differences involves a replacement of asparagine-34, with covalently attached carbohydrate on all molecules, in the river-breed enzyme by serine in the swamp-breed enzyme. The ribonuclease content of the pancreas differs considerably between breeds and is lower in river buffaloes. A ribonuclease preparation from two swamp buffaloes contained a minor glycosylated component. Preliminary evidence was obtained that the amino acid sequence of this component has factors in common with the main component of the swamp-breed ribonuclease and with the river-breed enzyme.
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PMID:Amino acid sequence differences in pancreatic ribonucleases from water buffalo breeds from Indonesia and Italy. 54 6

The trimerization constants of glucagon at pH 10.6 in 0.76 M K2HPO4 have been calculated from circular dichroism data between 5 and 50 degrees C. The free energy, enthalpy, and entropy of transfer have been evaluated from the current results and published data in 0.20 M phosphate. The free energies of transfer are derived completely from an increase in the entropy of transfer, since the enthalpy of transfer is less favorable at all temperatures. These parameters are compared with those of various model groups and compounds: CH2, peptide, methane, ethane, and the 1--13 N-terminal fragments of ribonuclease. The effects of fluoride and chloride on the self-association of glucagon have been compared with that of phosphate at 25 degrees C. These effects are consistent with the binding of approximately one molecule of salt to the trimer and a systematic decrease in the number of water molecules bound to the trimer compared to the monomer for the series K2HPO4, KF, and KCl.
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PMID:Effects of Hofmeister salts on the self-association of glucagon. 64 94

Adenylate cyclase from purified beef thyroid membranes has been solubilized by the use of Triton N-101 after preactivation with guanosine 5'-(beta, gamma-imido)-triphosphate. The soluble activity passed a 0.22- micron filter, was not sedimented at 100,000 X g for 2 h, and behaved like aldolase in sucrose density gradients and on Sepharose 6B. From comparison of the sedimentation in D2O and H2O the partial specific volume was found to be like that of globular proteins (0.75 +/- 0.006), hence little detergent appeared to be bound to the enzyme. The sedimentation coefficient was 7.4 +/- 0.15, the Stokes radius 45 A, and the molecular weight 159,000. Prestimulation by thyrotropin did not survive solubilization. The stimulation produced by guanosine 5'-(beta, gamma-imido)triphosphate persisted as did the more active state resulting from pretreatment with both this nucleotide plus thyrotropin. Thyrotropin did not stimulate the solubilized enzyme. The Km for ATP, thermal stability, and inhibition by Ca2+ were identical for the membrane-bound and soluble enzyme, while the pH optimum was increased 0.5 unit in the latter. Polyanions and phenothiazines inhibited both preparations equally, whereas only membranes responded to stimulation by polylysine and ribonuclease.
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PMID:Soluble adenylate cyclase from thyroid membranes. 67 Jan 96

Preparations of pancreatic RNAase, ribonuclease Act. rimosus and nuclease Ser. marcescens covalently bound to water-soluble derivatives of polysaccharides (m-aminobenzyl-oxymethyl ether of dextran and mannan, 4beta-oxyethylsulphonylanisol, 4beta-oxyethylsulphonylaniline, 3-Cl-2-oxypropyl ethers of dextran and dialdehydedextran) have been obtained. The yields and thermal stability of immobilized nucleases depend both upon the amount and nature of the functional groups which activate the polysaccharide. Polysaccharide aminoaryl ethers capable of binding to proteins by azocoupling present special interest in view of their utilization as modifying baskings. Regulation of effectiveness of the azocoupling reaction by means of structural changes of the diazocomponent and the reaction conditions were shown. All this allows to obtain immobilized enzymes with different physico-chemical properties.
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PMID:[Modification of nucleases by soluble derivatives of polysaccharides]. 73 15

IR-technique was used to study the effect of yeast cells treatment by water-alcohols mixtures on the quantitative relationship between the intensities of different bands in the spectra. The analysis of spectra made it possible to suggest that the reflection of the IR-irradiation from the cell is governed by the nucleoprotein layer of its envelope. It is shown that the treatment of yeast cell with ribonuclease raises the "IR-permeability" of the cell envelope.
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PMID:[Effect of yeast cell membrane components on the IR spectrum of the cell]. 79 69

Lipopolysaccharides, extracted by phenol-water from five strains fo Neisseria gonorrhoeae, were purified by treatment with ribonuclease followed by multiple washes. These preparations were fatal to mice when administered in submicrogram amounts with actinomycin D, the LD50 values varying from 4 to 16 mug/kg. Analyses showed that all preparations contained glucose, galactose, glucosamine, heptose, 2-keto-3-deoxyoctonic acid and phosphate. All the lipopolysaccharides contained the same fatty acids, namely beta-OH-10:0, beta-OH-12:0, beta-OH-14:0, 12:0, 14:0,16:0, 16:1, 18:0 and 18:1. We were unable to detect significant differences between the lipopolysaccharides of virulent and avirulent gonococci or between penicillin-sensitive and resistant strains. Gonococcal lipopolysaccharides appeared to lack O-antigen side chains.
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PMID:Studies on lipopolysaccharides isolated from strains of Neisseria gonorrhoeae. 80 76

Spleen lymphocytes of BCG-immunized mice contain a soluble factor that inhibits in vitro the growth of the H37Rv strain of Mycobacterium tuberculosis within normal peritoneal macrophages. The water-soluble extracts of sensitized lymphocytes, disrupted by freezing and thawing, although less active than the corresponding viable cells retained a significant growth-inhibiting activity. Dialysis against distilled water, lyophilization, exposure to ribonuclease and deoxyribonuclease, and storage at -20 degrees C of the water-soluble extracts did not affect their antimycobacterial activity, whereas extracts heated at 100 degrees C were completely devoid of such an activity. All the inhibiting activity was recovered in the void volume of the column after chromatography on Sephadex G-200. Water-soluble constitutents of sensitized lymphocytes did not affect BCG grown in vitro, and on repeated treatments of tuberculous mice they led to a negligible protection against pulmonary tuberculosis. Preliminary observations seem to indicate that other soluble factors in lymphocytes of BCG-sensitized mice have the capacity to potentiate in vitro the phagocytic activity of normal macrophages.
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PMID:Partial characterization of a factor extracted from sensitized lymphocytes that inhibits the growth of Mycobacterium tuberculosis within macrophages in vitro. 82 9

Steady state inactivation data on dilute aqueous solutions of RNase show that all water radicals, e-aq, OH, and H are responsible for the inactivation, but the most efficient radical is H atom, only about 4 of them being required for one inactivating event. The data are, therefore, more in agreement with the conclusions of Mee et al. (1972). In the transient absorption spectra of pulse irradiated ribonuclease different components derived by the individual radicals are observed. Organic and inorganic selenium-containing compounds offer a great protection of the enzyme activity, in agreement with the data obtained in other chemical and biological systems. In particular the effects of two new secondary radicals (CNSe)-2 and SeO-3 are in good accord with the known structure of ribonuclease.
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PMID:Further investigation on the radiation induced inactivation of ribonuclease and the radioprotective effect of some selenium-containing compounds. 92 59

The effects of a combination of an alcohol and urea on the transition temperature of bovine ribonuclease were investigated. The combined effects on the transition temperature of ribonuclease of a polyvalent alcohol and urea are about equal to the algebraic sum of the effects of each individual additive. The effects of a monovalent alcohol and urea are not cummulative, especially not at low temperatures (30 degrees C). The presence of urea decreases the hydrophobic effect of a monovalent alcohol, strongly at low temperatures, to a lesser degree at high temperatures (60 degrees C). Consequently, urea hinders the interhydrophobic interactions by affecting the water molecules.
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PMID:The effects from combining urea and an alcohol on the heat-induced reversible denaturation of ribonuclease. 94 44

The present paper describes intracellular changes in ribonuclease specific activity during Ca2+-induced sporangium formation in the water mold Achyla bisexualis. The enzymes undergo a decrease in activity prior to crosswall formation followed by an increase in activity during spore cleavage. As spore discharge occurs the RNase activity again decreases. A large percentage of the nuclease activity is associated with a lysosomal-like fraction of the cell, but there is also considerably activity associated with nuclear and microsomal fractions. Addition of cycloheximide or actinomycin D at various times during development prevents further decrease or increase in the enzyme activity. Mixing of cell extracts from different developmental stages provides evidence that inhibitors or activators of the enzyme activity are not responsible for the activity levels evident at the different stages. There is a change in the total levels of presumptive mRNA during Ca2+-induced sporangial formation which appears to be associated with the patterns of RNase activity. Utilizing total cellular RNA and Poly(A)+ RNA with the crude ribonuclease preparations, no substrate specificity could be ascertained.
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PMID:The development patterns of lysosomal enzyme activities during Ca2+-induced sporangium formation in Achyla bisexualis. III. Ribonucleases. 98 98


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