Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.4 (trypsin)
 42,187 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Crude preparations of secretin or pancreozymin increased and at higher concentrations decreased guanylate cyclase (GTP pyophosphate-lyase, EC 4.6.1.2) activity from soluble and particulate fractions of rat liver homogenates. Partially purified and synthetic secretin were without effect as was the biologically active octapeptide fragment of pancreozymin. The active contaminants in these preparations survived boiling, saponification, and treatment with phospholipase A, trypsin and neuraminidase C. The activity was extractable with chloroform/methanol and did not survive ashing. Eight bile salt contaminants in crude secretin were obtained with thin-layer chromatography. Two of the contaminating bile salts that increased liver particulate guanylate cyclase activity were identified as taurodeoxycholate and either glycochenodeoxycholate or glycodeoxycholate; taurocholate was inhibitory. The sodium salts of cholate, deoxycholate, chenodeoxycholate and their glycine-or taurine-conjugated forms either increased or decreased particulate and soluble rat liver guanylate cyclase activity depending upon their concentration. Thus, the previously reported stimulatory and inhibitory effects of secretin and pancreozymin preparations on guanylate cyclase activity are probable attributable to their bile salt contaminants.
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PMID:Activation of liver guanylate cyclase by bile salts and contaminants in crude secretin and pancreozymin preparations. 1 19

Some properties of a strain of mouse hepatitis virus, MHV-2, grown on DBT cells were determined using a plaque assay on the cells. Viral growth was not inhibited by the presence of actinomycin D or 5-iodo-2-deoxyuridine. MHV-2 was completely inactivated by ether, chloroform, sodium deoxycholate or beta-propiolactone, but showed a moderate resistance to trypsin. Heating at 56 C for 30 min did not completely abolish the virus infectivity. The virus was stable after heating at 50 C for 15 min in 1M-MgCl2 or 1M-MgSO4 as well as at 37 C for 60 min at pH 3.0 to 9.0. Infectivity was decreased to 1/100 and 1/400 after storing at 4 C for 30 days and 37 C for 24 hr, respectively. The virus passed through a 200-nm but not a 50-nm Sartorius membrane filter. The buoyant density of MHV-2 was 1.183 g/cm3 in sucrose gradient, and the fraction contained coronavirus-like particles measuring 70 to 130 nm in diameter. Survival rate was 10% after exposure to ultraviolet at 150 ergs/mm2. Freezing and thawing or sonication at 20 kc for 3 min did not affect the virus titer. No hemagglutinin was demonstrable with red blood cells of the chicken, Japanese quail, mouse, rat, hamster, guinea pig, sheep, bovine or human.
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PMID:Physico-chemical properties of mouse hepatitis virus (MHV-2) grown on DBT cell culture. 3 Aug 81

Earlier studies have shown that a substance(s) released from the egg jelly of the toad Bufo arenarum is required for fertilization. In this paper some properties of this diffusible factor were further examined, and a procedure was designed for its isolation from crude egg extracts. The active component is soluble in water and ethanol, and insoluble in chloroform, ether and n-butanol. The biological activity is stable to liophylization and to heat, and remains unaffected after trypsin treatment. In contrast, it is impaired after treatment with ethyl acetate, 0.1 N HCl or chloroform, and is completely destroyed after converting the diffusible factor into ash. Data are presented showing that the recovery of fertilizability of extracted eggs in the bioassay system as carried out under present conditions, cannot be ascribed to a pH alteration of the insemination medium. This lends further support to the view that diffusible factor activity is not mediated through a pH effect. The factor was purified by gel chromatography coupled with desalting and paper chromatography. The active molecule is of low molecular weight and appears associated with a high pH ninhydrin-positive fraction.
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PMID:Properties and isolation of the diffusible factor involved in Bufo arenarum fertilization. 11 83

p-Nitrobenzyl p-toluenesulfonyl-L-arginine has been synthesized. A number of trypsin-like enzymes can catalyze the hydrolysis of this ester leading to formation of p-nitrobenzyl alcohol. After separation from the ester and p-toluenesulfonylarginine by extraction into chloroform, the p-nitrobenzyl alcohol liberated can be measured spectrophotometrically at 271 nm. Under the conditions of the assay, the hydrolysis of 1 micronmol/ml of the ester is equivalent to an absorbance change of 4.45 cm-1 at 271 nm. With 0.10 mM p-nitrobenzyl p-toluenesulfonyl-L-arginine in 0.1 M Tris-HCl at pH 8.4 and 30 degrees, the enzymatic hydrolysis is linearly proportional to time up to consumption of 60% of the ester. Product formation is proportional to enzyme concentration with 0.05 to 0.2 NIH clotting units/ml for bovine or human thrombin, 0.005 to 0.02 CTA units/ml for human plasmin, and 0.01 to 0.04 microgram/ml protein for bovine pancreatic trypsin. In 0.1 M Tris-HCl at pH 8.4 and 30 degrees, Km is 14 micrometer and Vmax is 0.037 micronmol/min/NIH unit/ml for bovine thrombin, Km is 78 micrometer and Vmax is 0.31 micronmol/min/CTA unit/ml for human plasmin, and Km is 12 micrometer and Vmax is 138 micronmol/min/mg protein/ml for bovine trypsin. With bovine thrombin, activities at pH 7.3 and at pH 9.2 were 30% lower and 40-50% higher than the rate at pH 8.4. Samples of bovine and human thrombin ranging in specific clotting activity from 59 to 2133 NIH units/mg protein showed esterase activities varying from 0.15 to 0.4 micronmol p-nitrobenzyl alcohol formed/10 min/NIH unit.
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PMID:Assay of the esterase activity of thrombin, plasmin and trypsin with a chromogenic substrate p-nitrobenzyl p-toluenesulfonyl-l-arginine. 14 54

A cytopathogenic virus was isolated in the primary culture of bovine kidney cells from a nasal swab of affected calves in an outbreak of acute respiratory disease in Japan in 1971. It agglutinated human type O erythrocytes and produced cytoplasmic inclusion bodies. Viral replication was inhibited by 5-iodo-2'-deoxyuridine, indicating that the viral nucleic acid was RNA. The virus was resistant to ether, chloroform, sodium deoxycholate, and acid, and passed readily through Sartorius' membrane filter 100 nm in pore size, but not through the filter 50 nm in pore size. Electron microscopy showed many spherical particles 60 approximately 75 nm in diameter with a double-layered capsid in a sample taken at a buoyant density of 1.34 produced by CaCl equilibrium centrifugation. The virus suspended in 1M MgCl2 solution was stable against heating at 50 degrees C for 30 minutes, but not against freezing at -20 degrees C for 60 minutes. The virus was resistant to, and increased in infectivity after, treatment with 0.063 approximately 1.0% trypsin. These properties were consistent with those established for the reoviruses. Most affected cattle showed a significant rise of antibody titer against reovirus and bovine respiratory syncytial virus, whereas only a few of them presented a serological evidence for recent infection with parainfluenza virus type 3, bovine adenovirus type 7, and bovine parovirus.
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PMID:Isolation and properties of reovirus from cattle in an outbreak of acute respiratory disease. 18 78

Outbreaks of inclusion body hepatitis were observed in broiler chickens on a poultry farm during 3 years. Avian adenovirus-like agents were isolated during these years from livers of diseased chickens. Round-cell-type cytopathogenic effect and intranuclear inclusion bodies were produced in chicken kidney cell cultures inoculated with these agents. Properties of the agents were as follows: resistant to ether, chloroform, socium deoxycholate, trypsin, heating at 50 C, and pH 3.0; sensitive to 5-iodo-deoxyuridine; and pathogenic to chicken embryos. From these properties and ultrastructural findings of the agents, these were identified as avian adenovirus. Day-old commercial chicks were insusceptible to these viruses. Maternal antibody levels in commercial chicks were considerable. Surveys for neutralizing index to the virus were performed on chickens in the field, and all sera tested were positive. Electron-microscope examination showed that these viruses contained avian-adenovirus-associated virus.
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PMID:Some properties of avian adenoviruses isolated from chickens with inclusion body hepatitis in Japan. 18 9

A viral agent, designated Id-1, was isolated from the buffy coat of a calf suffering from weak calf syndrome. The virus replicated on bovine salivary gland cells and caused cytopathic effect within four days after infection-Cytopathic effect was characterized by rounding and clumping of cells. Stained preparations of infected monolayers revealed multiple intranuclear inclusions. The agent was found to be resistant to chloroform, ether, trypsin, sodium desoxycholate, oxytetracycline and a pH range of three to nine. The virus was sensitive to 5-iodo-2'-deoxyuridine and to a temperature of 70 degrees C. Cross neutralization tests with Id-1 antiserum and bovine adenovirus type 7 (strain Fujuroi) antiserum resulted in complete neutralilation of both viruses with four or less antibody units of homologous or heterologous antiserum.
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PMID:Isolation of a subgroup two adenovirus from calf with weak calf syndrome. 18 93

A virus was isolated from the spleen of a white-tailed deer (Odocoileus virginianus) that had died during an epizootic in Washington state in 1967. Inoculation of a 10% spleen suspension from the deer caused hemorrhagic disease in normal white-tailed deer. Studies were conducted on the biological, physicochemical, and serologic properties of the Washington isolate. An in vitro assay system, utilizing a cultured primary of white-tailed deer fetal cells from an entire fetus, was employed for isolation and propagation of the virus. Cytopathic effect was characterized by focal development of rounded and clumped cells. Propagation was unsuccessful in suckling mice, BHK-21, and Vero cell cultures. The virus was resistant to treatment with ether, sodium deoxycholate, trypsin, oxytetracycline hydrochloride, and was sensitive to chloroform. Virus yield was not affected when infected cultures were treated with 5-iodo-2'-deoxyuridine, but dactinomycin (actinomycin D) treatment of infected cultures reduced virus yield. The virus was inactivated when heated at 70 C for 5 minutes or when exposed to pH 5 for 18 hours at 4 C. The virus was completely excluded from the filtrate by a 0.10- micronm (APD) membrane filter. Staining of infected cells with acridine orange indicated the presence of double-standard nucleic acid in the cytoplasm. Serum-neutralization tests with antiserums against the homologous virus and the New Jersey and Alberta strains of epizootic hemorrhagic disease virus resulted in neutralization of the Washington isolate. The Washington virus was not neutralized by bluetongue virus antiserum. Cells infected with the Washington isolate exhibited intracytoplasmic fluorescence by the indirect fluorescent antibody method with New Jersey and Alberta epizootic hemorrhagic disease antiserums but not with bluetongue antiserum.
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PMID:Isolation and characterization of epizootic hemorrhagic disease virus from white-tailed deer (Odocoileus virginianus) in eastern Washington. 19 10

Three strains of adenovirus were relatively stable to the effects of chloroform, extreme pH, trypsin, heat, lyophilization, and ultrasonication. The structure of the viruses and their mode of replication in cell cultures confirmed these viruses to be members of the avian adenoviruses.
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PMID:Characteristics of three strains of avian adenoviruses isolated in Queensland. II. Biochemical, biophysical, and electron-microscope studies. 23 54

Studied were some physico-chemical properties of four CELO virus strains isolated in Bulgaria. Their behaviour to ether, chloroform and 25 per cent trypsin, and their state at 56 degrees C and at pH 3, 0 were determined through their infectious titer as obtained on 9--10-day old chicken embryos. It was found that the size of the investigated viruses is within the range of 50 to 100 mmu, they belong to the DNA-possessing group, are resistant at 56 degrees C and at pH EQUALS 3,0. They are not sensitive to ether, chloroform and trypsin. Their physico-chemical properties are fully comparable with those of the avian adenoviruses-CELO.
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PMID:[Physico-chemical properties of CELO virus strains isolated in Bulgaria]. 23 18


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