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)

A quick and simple method has been developed for the recovery of proteins from water-in-oil microemulsions (w/o-MEs), which is needed to further the use of liquid-liquid extraction in bioseparations. By adding a small portion (0.1 v/v or less) of cosurfactant (e.g., 1-alkanol) to w/o-ME solution, proteins were readily expelled, sometimes as solids, while most or all of the surfactant (Aerosol OT) remained in solution. The release of proteins increased with the further addition of cosurfactant and was greater when the molar ratio of protein to w/o-ME or fractional occupancy (f) was high. However, protein expulsion was also significant when f was small. The addition of cosurfactant released ribonuclease, lysozyme, alpha-chymotrypsin, pepsin, bovine serum albumin (BSA), and catalase from w/o-ME solution, but the expulsion was greater for BSA relative to chymotrypsin and lysozyme. Protein expulsion also increased with cosurfactant chain length for the homologous series of 1-alkanols starting at 1-butanol; however, water was also coexpelled in significant amounts. An exception to the latter rule was 1-butanol, which readily promoted the release of protein, but not encapsulated water. The addition of 1-butanol to a w/o-ME solution containing alpha-chymotrypsin and BSA selectively released the former protein, with chymotryptic activity occurring in the recovered protein. Possible mechanisms for the cosurfactant-mediated release of protein are discussed. Copyright 1998 John Wiley & Sons, Inc.
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PMID:Expulsion of proteins from water-in-oil microemulsions by treatment with cosurfactant 1009 72

Alkyl-substituted hydroxybenzenes (AHBs), auto-inducers of microbial dormancy (or d1 factors), were found to stabilize the structure of protein macromolecules, making them metabolically less active and more resistant to stresses. In vitro experiments with the Bacillus intermedius ribonuclease and chymotrypsin showed that the degree of the physical and chemical stability of these enzymes treated with AHBs depends on their concentration and incubation time. Experiments with RNase, which is capable of refolding, i.e., renaturation after heat denaturation, revealed that AHBs efficiently interact with both intact and denatured proteins. The data obtained allow the inference to be made that d1 factors may play the role of natural chemical chaperons, blocking metabolism in dormant cells through the formation of catalytically inactive thermostable complexes with enzymes.
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PMID:[Stabilization of enzymes by anabiosis autoinducers as a possible mechanism of resistance of resting microbial forms]. 1077 22

Further studies on fever production by injection of leukocyte extracts or cell-free supernatant fluids from peritoneal exudates in rabbits are reported. Granulocytes collected from peripheral blood or from pleural exudates contain a heat-labile pyrogenic substance. The material in extracts of leukocytes and in peritoneal fluids, which causes fever, is destroyed by heating for 30 minutes at 90 degrees C. at pH 7.2 and at 70 degrees C. at pH 4.5. It is active in producing fever over a pH range of 2.0 to 10.5 and maintains potency for as long as 6 months at 4 degrees C. The fever-producing substance in leukocyte extracts is not dialyzable. Its activity is not destroyed by trypsin, chymotrypsin, or ribonuclease. No evidence of plasma activator or inhibitor was detected. Significant temperature elevation in the rabbit was effected by a quantity of leukocyte extract containing 0.76 mg. protein and 0.054 mg. polysaccharide. The febrile response produced by the material under study was compared with that of Menkin's pyrexin as well as with that of bacterial pyrogens. Several significant differences were noted. The properties of pyrexin are similar to those of bacterial pyrogens. Amidopyrine suppressed the febrile response to injection of leukocyte extracts, whereas neither amidopyrine nor cortisone influenced the appearance of pyrogenic material in induced peritoneal exudates. Peritoneal fluids collected from rabbits made leukopenic by HN(2) were found to contain a fever-promoting substance. Its character has yet to be determined. It is concluded that there is present in polymorphonuclear leukocytes of rabbits a heat-labile factor capable of producing fever in rabbits and that the leukocyte is probably not the only source of such a factor.
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PMID:Studies on the pathogenesis of fever. II. Characterization of fever-producing substances from polymorphonuclear leukocytes and from the fluid of sterile exudates. 1310 5

1. The hemagglutinating capacity, enzymic activity, and infectivity of several influenza viruses were destroyed by repeated freezing and thawing of dialyzed allantoic fluids containing them. 2. Influenza virus degraded by freezing and thawing, by treatment with 5 M urea, or by heating at 65 degrees C. still combined with homologous antibody and was demonstrable by blocking of the hemagglutination-inhibition and virus neutralization reactions. 3. After 50 cycles of freezing and thawing, much of the blocking antigen activity was not sedimented by centrifugation at 120,000 g for 2 hours, and electron microscopy showed complete disruption of the virus particles. So called soluble blocking antigen was obtained from four strains of influenza A, the Lee strain of influenza B, mumps, and Newcastle disease viruses. 4. Soluble blocking antigens from influenza A viruses were highly strain-specific; gave little or no reaction in complement-fixation tests; stimulated but little antibody production in rabbits and did not induce immunity in mice; caused reactivation of infective virus in neutral mixtures of homologous virus and immune serum. 5. Repeatedly frozen and thawed influenza virus preparations did not interfere with the propagation of infective virus in the allantoic sac. The blocking antigen activity they contained was precipitated by half saturated ammonium sulfate, destroyed by trypsin, chymotrypsin, or heating at 56 degrees C. for 30 minutes, but was unaffected by desoxyribonuclease or ribonuclease. 6. These findings are in accord with the view that soluble blocking antigen obtained from influenza virus particles on disruption by repeated freezing and thawing is protein in nature and represents the essential antigenic material of the intact virus.
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PMID:Disruption of influenza virus; properties of degradation products of the virus particle. 1315 79

Lambda coli phage is not inactivated by chymotrypsin, trypsin, or ficin. T(2) phage is slowly inactivated by high concentrations of (alpha-, beta-, gamma-, or Delta-chymotrypsin, but not by trypsin or ficin. P(1) phage is slowly inactivated by alpha-, beta-, or gamma-chymotrypsin, or ficin, more rapidly by Delta-chymotrypsin, and much more rapidly by trypsin. Crystalline egg albumin, crystalline serum albumin, E. coli nucleoprotein, and yeast nucleoprotein are hydrolyzed slowly by alpha-chymotrypsin. Yeast nucleoprotein, like P(1) phage, is hydrolyzed more rapidly by Delta-chymotrypsin than by alpha-chymotrypsin, but not by trypsin or ficin. Neither phages nor native proteins were attacked by papain, carboxypeptidase, deoxyribonuclease, or ribonuclease.
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PMID:THE EFFECT OF PROTEOLYTIC ENZYMES ON E. COLI PHAGES AND ON NATIVE PROTEINS. 1421 51

Agglutinability of human erythrocytes for 3 hemagglutinating adenoviruses was markedly reduced by pretreatment of red cells with a factor present in tissue cultures which had been infected with adenovirus types 1, 2,4, or 15. The factor responsible for erythrocyte receptor modification was non-dialyzable and unaffected by the action of ribonuclease, desoxyribonuclease, trypsin, chymotrypsin, or ether. The factor was smaller, more thermostable, and separable from the infectious virus. Erythrocyte receptor modification was found to be a function of time and temperature. Titers of erythrocyte receptor-modifying activity were not diminished by successive exposures to fresh erythrocytes. Erythrocytes treated with erythrocyte receptor-modifying factor suspensions failed to significantly adsorb test virus hemagglutinin. Inhibition of erythrocyte receptor modifying-activity of the adenovirus suspensions by rabbit antiserum was type-specific.
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PMID:Further characterization of the adenovirus erythrocyte receptor-modifying factor. 1445 30

A heterodimeric 13.8 kDa napin-like polypeptide has previously been isolated from Chinese cabbage (Brassica parachinensis) seeds with a procedure involving ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, FPLC-ion exchange chromatography on Mono S and FPLC-gel filtration on Superdex 75. In the present study the N-terminal sequence of the 8.8 kDa subunit of the polypeptide (PQGPQQRPPKLLQQQTNEEHE) was found to have pronounced homology to napins, albumins and trypsin inhibitors, but demonstrated little similarity to the 5 kDa subunit. The polypeptide stimulated nitrite production by mouse peritoneal macrophages and reduced the viability of leukaemia (L1210) cells. It inhibited trypsin with a higher potency than it inhibited chymotrypsin, but was devoid of ribonuclease and antifungal activities.
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PMID:The trypsin-inhibitory, immunostimulatory and antiproliferative activities of a napin-like polypeptide from Chinese cabbage seeds. 1499 88

Napins are 1:1 disulfide-linked complexes of a smaller (ca. 4kDa) subunit and a larger (ca. 10kDa) subunit. The intent of the present study was to ascertain the production of napin by the seeds of a Brassica species that has not been examined previously, and also to explore new biological activities of the napin. A heterodimeric 11-kDa napin-like polypeptide has been isolated from Chinese white cabbage (Brassica chinensis cv dwarf) seeds with a protocol comprising ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, fast protein liquid chromatography (FPLC)-ion exchange chromatography on Mono S and FPLC-gel filtration on Superdex 75. The N-terminal sequence of the 7-kDa subunit manifests striking similarity to napin large chain, albumin and trypsin inhibitor. The N-terminal sequence of the 4-kDa subunit is homologous to napin large chain and an antimicrobial peptide. The napin-like polypeptide inhibited translation in the rabbit reticulocyte system with an IC50 of 18.5nM. This translation-inhibitory activity was stable between pH 4 and 11, and between 10 and 40 degrees C. The polypeptide inhibited trypsin with a higher potency ( IC50 = 8.5 microM) than it inhibited chymotrypsin (IC50 = 220 microM), but was devoid of ribonuclease and antifungal activities. It manifested antibacterial activity against Pseudomonas aeruginosia, Bacillus subtilis, Bacillus cereus, and Bacillus megaterium. The results revealed that the napin-like polypeptide from Chinese white cabbage seeds exhibited some potentially exploitable activities.
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PMID:A napin-like polypeptide from dwarf Chinese white cabbage seeds with translation-inhibitory, trypsin-inhibitory, and antibacterial activities. 1506 97

A protein designated alliumin, with a molecular mass of 13 kDa and an N-terminal sequence similar to a partial sequence of glucanase, and demonstrating antifungal activity against Mycosphaerella arachidicola, but not against Fusarium oxysporum, was isolated from multiple-cloved garlic (Allium sativum) bulbs. The protein, designated as alliumin, was purified using ion exchange chromatography on DEAE-cellulose, CM-cellulose and Mono S, affinity chromatography on Affi-gel blue gel, and gel filtration on Superdex 75. Alliumin was unadsorbed on DEAE-cellulose, but was adsorbed on Affi-gel blue gel, CM-cellulose and Mono S. Its antifungal activity was retained after boiling for 1 h and also after treatment with trypsin or chymotrypsin (1:1, w/w) for 30 min at room temperature. Alliumin was inhibitory to the bacterium Pseudomonas fluorescens and exerted antiproliferative activity toward leukemia L1210 cells. However, it was devoid of ribonuclease activity, protease activity, mitogenic activity toward mouse splenocytes, and antiproliferative activity toward hepatoma Hep G2 cells.
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PMID:Isolation of alliumin, a novel protein with antimicrobial and antiproliferative activities from multiple-cloved garlic bulbs. 1562 28

Syringacin 4-A, a bacteriocin produced by Pseudomonas syrinagae 4-A, was obtained by induction with ultraviolet irradiation or mitomycin C. Approximately 1,000-fold purification of the bacteriocin was achieved by manganous chloride precipitation, differential centrifugation, and chromatography on hydroxyapatite columns. The purified syngacin was homogeneous on hydroxyapatite columns and sucrose density gradients; it also sedimented as a single entity in the analytical ultracentrifuge. The buoyant density of purified syringacin in cesium chloride was 1.294 g/ml. The sedimentation coefficient was calculated as 120S, and the diffusion coefficient was 6.49 x 10(-8) cm(2)/s. The molecular weight was calculated as 1.6 x 10(7) from physical data and 1.7 x 10(7) from biological data. The syringacin was composed of about 88.4% protein, 8.5% arabinose, 2.2% galacturonic acid, and 0.7% glucosamine. Amino acid analysis indicated a predominance of leucine (12.1%), aspartic acid (12.2%), and glutamic acid (12.7%). The ultraviolet spectrum showed a maximum absorbance peak at 276 nm. The syringacin was heat and alcohol sensitive, but resistant to trypsin, chymotrypsin, carboxypeptidase, Pronase, protease, lysozyme, steapsin, deoxyribonuclease, and ribonuclease. Maximum pH stability was between 5 and 8. Crude bacteriocin was stable at room temperature for at least a year, and purified material was stable for at least 3 months at 4 C.
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PMID:Purification and characterization of syringacin 4-A, a bacteriocin from pseudomonas syringae 4-A. 1582 74


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