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 molybdenum requirement for growth and conidial formation by Aspergillus flavus, A. terreus, and A. sulphureus was found to be 0.2 ppb, which was one-fifth that of an A. niger isolate. Molybdenum deficiency depressed growth, conidial formation, dry weight, soluble protein, and the specific activities of nitrate reductase, succinic dehydrogenase, and aconitase in all the isolates of Aspergillus studied, but the specific activities of catalase and peroxidase were depressed only in isolates of A. niger, A. terreus, and A. flavus. Also, molybdenum deficiency stimulated the specific activities of acid phosphatase and ribonuclease in the A. flavus isolate, although the specific activities of these enzymes decreased in other isolates. Eighteen hours after the addition of molybdenum (5 ppb) to molybdenum-deficient (0.02 ppb) cultures of A. niger, the specific activities of catalase, peroxidase and succinic dehydrogenase were restored in the absence of cycloheximide, while the specific activity of nitrate reductase was recovered even in the presence of the inhibitor. There was no effect on the specific activities of aconitase and acid phosphatase following the addition of molybdenum to molybdenum-deficient cultures of A. niger.
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PMID:Molybdenum nutrition of isolates of four Aspergillus species. 309 Dec 28

Homogenates of Giardia lamblia trophozoites exhibited the following hydrolase activities: acid phosphatase (EC 3.1.3.2), proteinase (EC 3.1.4) with urea-denatured hemoglobin and N-benzoyl-DL-arginine-2-naphthylamide as substrates, deoxyribonuclease (EC 3.1.4.5), and ribonuclease (EC 2.7.7.16). beta-N-Acetylglucosaminidase (EC 3.2.1.30), beta-galactosidase (EC 3.2.1.23), beta-glucuronidase (EC 3.2.1.31), alpha-D-glucosidase (EC 3.2.1.20), beta-D-glucosidase (EC 3.2.1.21), and beta-D-xylosidase (EC 3.2.1.37) activities were below the level of detection. Differential and isopycnic centrifugation of homogenates demonstrated that giardial hydrolases were localized in a single-particle population sedimenting at 7200g for 30 min. The particles had a buoyant density in sucrose of 1.15 and exhibited latency. Latency was completely destroyed by Triton X-100 or 15 cycles of freezing and thawing. After centrifugation of Triton- or freeze-thaw-treated particle fractions, the hydrolase activities, though no longer latent, were still sedimentable suggesting tight binding to the organelle membrane. Latency was destroyed simultaneously for all hydrolases, in direct proportion to the amount of Triton added to a particle preparation or to the number of times a particle preparation was subjected to freezing and thawing. These results support the suggestion that the hydrolases of G. lamblia trophozoites are localized in a single-particle population of lysosome-like organelles.
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PMID:Giardia lamblia: localization of hydrolase activities in lysosome-like organelles of trophozoites. 327 50

The levels of pancreatic digestive enzymes, lysosomal hydrolases, and protease inhibitors were evaluated in ascites fluid from 24 patients with acute pancreatitis diagnosed as alcoholic, gallstone-induced, or idiopathic. In this group the concentrations of amylase (354 +/- 98 ng/ml), immunoreactive cationic trypsinogen (1840 +/- 238 ng/ml), and immunoreactive elastase 2 (1492 +/- 262 ng/ml) were greatly elevated in comparison to the corresponding serum values. Enzyme levels in ascites from the idiopathic pancreatitis group tended to be higher than the levels from the other two groups. Activity of acid phosphatase and beta-glucuronidase was significantly higher in ascites compared to serum in all groups. On the other hand, levels of immunoreactive alpha 1-protease inhibitor and alpha 2-macroglobulin in ascites fluid were about half the average concentrations reported for normal serum. Significant amounts of tryptic amidase activity (61.7 +/- 13.7 micrograms/ml) were observed, indicating a trypsin-alpha 2-macroglobulin complex. These data indicate an imbalance in the protease-to-inhibitor ratio in ascites fluid from patients with acute pancreatitis. Coupled with elevated ribonuclease activity (27.4 +/- 3.4 units), a positive methemalbumin test in 23 of 24 patients (1.1 +/- 0.4 mg hematin/100 ml), and an average protein concentration of 4.0 +/- 0.2 g/100 ml, these observations demonstrate that abdominal paracentesis and the biochemical analyses of ascites fluid provide useful information related to the biochemical events in acute pancreatitis and may be useful in the diagnosis of difficult cases, but their predictive value of severity remains to be established.
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PMID:Biochemical studies in peritoneal fluid from patients with acute pancreatitis. Relationship to etiology. 381 84

The ingestion of (14)C-labeled 9,10-dimethyl-1,2-benzanthracene particles, the extracellular release of acid phosphatase, ribonuclease, and alpha-glucosidase, and the egestion of preingested dimethylbenzanthracene particles by Tetrahymena taken from logarithmically growing cultures and resuspended in a dilute salt solution were followed in the presence of several pharmacologic agents. Serotonin, caffeine, and, to a lesser extent, dibutyryl cyclic AMP increased the rate of particle ingestion, but did not alter the rate of release of the three acid hydrolases studied. Added catecholamines did not affect either particle ingestion or acid hydrolase release, but particle ingestion was inhibited by the catecholamine antagonists, dichloroisoproterenol, desmethylimipramine, reserpine, and phenoxybenzamine. These drugs also increased the release of acid phosphatase and ribonuclease in 5-h incubations. Desmethylimipramine acted within 1 h to increase acid hydrolase release, but the effect of dichloroisoproterenol developed more slowly and was secondary to a change in cellular content of the hydrolases. Desmethylimipramine increased the energy of activation for the release of acid phosphatase, while dichloroisoproterenol did not. Both of these drugs enhanced the egestion of preingested dimethylbenzanthracene particles, supporting the view that acid hydrolase release occurs through a cytoproct egestion mechanism. Particle ingestion was also inhibited by colchicine, vinblastine, and cytochalasin B, but these agents had no effect on acid hydrolase release, thus further differentiating the properties of the ingestion mechanism from those of the egestion mechanism. It appears that both microtubules and microfilaments play a role in the ingestion process and that this process may be controlled in part by a cyclic AMP-mediated serotoninergic and adrenergic system.
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PMID:Lysosomal physiology in Tetrahymena. 3. Pharmacological studies on acid hydrolase release and the ingestion and egestion of dimethylbenzanthracene particles. 415 46

1. The action of beryllium on the following enzymes has been examined: alkaline phosphatase (Escherichia coli and kidney), acid phosphatase, phosphoprotein phosphatase, apyrase (potato), adenosine triphosphatase (liver nuclei, liver mitochondria, brain microsomes), glucose 6-phosphatase, polysaccharide phosphorylases a and b, phosphoglucomutase, hexokinase, phosphoglyceromutase, ribonuclease, A-esterase (rabbit serum), cholinesterase (horse serum), chymotrypsin. Alkaline phosphatase and phosphoglucomutase are inhibited by 1mum-beryllium sulphate whereas the other enzymes are largely unaffected by 1mm-beryllium sulphate. 2. Possible mechanisms for the inhibition of phosphoglucomutase and alkaline phosphatase are discussed.
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PMID:The inhibition of enzymes by beryllium. 428 87

Electron microscope examination of the adrenal cortex from three male human subjects revealed a special type of cell occurring in periendothelial spaces, in all adrenal cortex zones. It is a clear, spindle-shaped cell the principal cytoplasmic features of which are crystalline inclusions with a structure similar to that of the Reinke crystals of human testicular interstitial cells and an abundance of microfilaments. Enzymatic digestions with pronase, pepsin, and ribonuclease were performed, and no digestion of the crystals was obtained. The crystals had no peroxidase or acid phosphatase activities. This cell appears to be exclusive to human males and it may be related to adrenal androgen secretion.
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PMID:A new crystal-containing cell in human adrenal cortex. 434 48

1. Development of ribonuclease activity in the cotyledons of germinating peas is biphasic, the time of appearance of the two phases depending on the conditions of growth. 2. Acid phosphatase exhibits a single phase of development. 3. Cycloheximide inhibits development of ribonuclease activity in phase II but not in phase I. 4. (14)C-labelled amino acids are not incorporated into ribonuclease isolated during phase I. 5. The buoyant density of ribonuclease isolated during phase I is not affected by imbibition of the seed in 80% deuterium oxide. 6. Acid phosphatase was isolated from the supernatant fraction of the cotyledons of germinating peas and partially purified. 7. Development of acid phosphatase activity during germination is inhibited by treatment of the seed with cycloheximide or actinomycin D. 8. Partial purification of acid phosphatase from peas germinated in the presence of (14)C-labelled amino acids suggests that the enzyme is radioactively labelled. 9. Germination of peas in the presence of 80% deuterium oxide results in an increase in the buoyant density of acid phosphatase. 10. The results suggest that increase in ribonuclease activity during the first 4 days of germination does not result from synthesis of protein de novo, but that the corresponding increase in acid phosphatase activity does result from synthesis de novo.
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PMID:The development of ribonuclease and acid phosphatase during germination of Pisum arvense. 444 77

Log-phase Tetrahymena were washed and resuspended in a dilute salt solution supplemented with glucose, acetate, pyruvate, or carmine, as desired, and then incubated for 5 h. Intra- and extracellular activities of acid phosphatase, alpha-glucosidase, and ribonuclease were assayed. Extracellular activities were corrected for proteolytic degradation. The three nutritive substrates affected both the amount and pattern of extracellular enzyme release, but carmine had no effect. Intracellular activities declined early in the starvation period, but partially recovered with time, particularly alpha-glucosidase activity. Acetate reduced the decline in acid phosphatase activity; acetate and glucose enhanced the recovery of alpha-glucosidase activity; carmine had no effect on intracellular enzyme activities. Protein content changed little and was unaffected by the addition of substrates. Glycogen content increased during incubation; acetate and glucose enhanced the increase.
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PMID:Lysosomal physiology in Tetrahymena. I. Effect of glucose, acetate, pyruvate, and carmine on intracellular content and extracellular release of three acid hydrolases. 463 42

1. Lysosome-rich fractions from rat liver were subjected to several disruptive procedures: osmotic lysis or freezing and thawing in different media, shearing forces in a high-speed blender, treatment with Triton X-100. 2. The soluble and particulate phases were then separated by high-speed centrifugation and assayed for their content of acid phosphatase, beta-galactosidase, beta-N-acetylglucosaminidase, acid proteinase, acid ribonuclease, acid deoxyribonuclease and protein. 3. The degree of elution of these hydrolases appeared to depend on both the enzyme species and the treatment. The resulting patterns of solubilization were rather complex, so that a clear-cut discrimination between soluble and structure-bound enzymes could not always be traced. 4. Although only beta-galactosidase was readily solubilizable after all treatments, acid proteinase could also be extensively eluted from the sedimentable material in the presence of EDTA and acid phosphatase was fully extracted by Triton X-100. On the other hand, considerable proportions of the other activities could not be solubilized by any of the procedures used. 5. In other experiments, the adsorbability of hydrolases on subcellular structures was investigated by measuring the partition between sedimentable particles and soluble fraction of solubilized enzymes added to ;intact' liver homogenates. 6. Large proportions of acid proteinase, ribonuclease and deoxyribonuclease, and almost all of beta-N-acetylglucosaminidase, were found to be adsorbed on the particulate material.
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PMID:Studies on the structure-bound sedimentabolity of some rat liver lysosome hydrolases. 511 7

Distribution of ribonuclease (RNAase), acid phosphatase (acid Ph-ase) and beta glucuronidase (BGU) between the granule, cytosol-soluble and post-granule fractions in normal human granulocytes and in granulocytes of chronic granulocytic leukemia (CGL) was studied. CGL granulocytes were found to display relative RNAase activity 1.2 times higher, relative acid Ph-ase activity 2.5 times higher than normal granulocytes. The granule fraction of CGL granulocytes showed 1.4 times higher relative RNAase activity but 0.87 times lower acid Ph-ase activity and the same BGU activity as normal granulocytes. On the other hand, the supernatant soluble fraction of CGL granulocytes showed 4.4 times higher relative RNAase activity, 1.2 times higher relative acid Ph-ase activity and BGU 2.2 times higher than in cytosol soluble fraction of normal granulocytes. Thus, cytosol soluble fraction of CGL granulocytes show a relative activity of the lysosomal enzymes studied which is remarkably higher than in normal granulocytes. The percentage distribution of RNAase, acid Ph-ase and BGU showed that CGL granulocytes contain only 36% of total RNAase activity versus 46% of that in normal ones. On the other hand, CGL granulocytes in cytosol soluble fraction will contain 48% of total RNAase versus 29% of total RNAase in cytosol of normal granulocytes. The isoenzyme profiles of RNAase of granule fractions were similar in normal and CGL granulocytes, while the RNAase isoenzyme profiles of cytosol fractions were different for normal and CGL granulocytes, indicating that some essential part of CGL granulocyte cytosol RNAase differs from RNAase contained in granules and in cytosol of normal granulocytes.
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PMID:Differences in distribution of ribonuclease isoenzymes in cytosol and granules in normal human granulocytes and in granulocytes of patients with chronic granulocytic leukemia (CGL). 620 Mar 92


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