Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.22.1 (DNase II)
 429 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Diphosphonates are known to inhibit bone resorption in tissue culture and in experimental animals. This effect may be due to their ability to inhibit the dissolution of hydroxyapatite crystals, but other mechanisms may be important. Since lysosomal enzymes have implicated in the process of bone resorption, we have examined the effect of several phosphonates and of a polyphosphate (P20,2) on lysosomal hydrolases derived from rat liver and rat bone. Dichloromethylene diphosphonate strongly inhibited acid beta-glycerophosphatase (EC 3.1.3.2) and acid p-nitrophenyl phosphatase (EC 3.1.3.2) and to a lesser degree (in descending order) acid pyrophosphatase (EC 3.1.3.-), arylsulfatase A (EC 3.1.6.1), deoxyribonuclease II(EC 3.1.4.6) and phosphoprotein phosphatase (EC 3.1.3.16) of rat liver. Inhibition of acid p-nitrophenyl phosphatase and arylsulfatase A was competitive. Ethane-1-hydroxy-1, 1-diphosphonate did not inhibit any of these enzymes, except at high concentrations. Neither dichloromethylene diphosphonate nor ethane-1-hydroxy-1, 1-diphosphonate had any effect on beta-glucuronidase (EC 3.2.1.31), arylesterase (EC 3.1.1.2) and cathepsin D (EC 3.4.23.5). Of several other phosphonates tested only undec-10-ene-1-hydroxy-1, 1-diphosphonic acid inhibited acid p-nitrophenyl phosphatase strongly, the polyphosphate (P20, I) had little effect. Acid p-nitrophenyl phosphatase in rat calvaria extract behaved in the same way as the liver enzyme and was also strongly inhibited by dichloromethylene diphosphonate, but not by ethane-1-hydroxy-1, 1-diphosphonate. It is suggested that the inhibition of bone resorption by dichloromethylene diphosphonate might be due in part to a direct effect of this diphosphonate on lysosomal hydrolases.
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PMID:The effect of several diphosphonates on acid phosphohydrolases and other lysosomal enzymes. 17 70

Leishmania mexicana mexicana (M379) amastigotes were found to contain much higher activities than cultured promastigotes of five putative lysosomal enzymes: cysteine proteinase; arylsulfatase (EC 3.1.6.1); beta-glucuronidase (EC 3.2.1.31); DNase (EC 3.1.22.1), and RNase (EC 3.1.27.1). The release profiles of the first three of these enzymes from digitonin-permeabilized amastigotes suggests that they are located within organelles. Cytochemical staining for cysteine proteinase, using gold labeled antibodies and arylsulfatase, showed that both were present in large organelles previously named "megasomes." Comparative studies with L. mexicana amazonensis (LV78), L. donovani donovani (LV9), and L. major (LV39) revealed that L. mexicana amazonensis was similar to L. mexicana mexicana in possessing both high amastigote cysteine proteinase activity and large numbers of megasome organelles in amastigotes, whereas the other two species lacked both these features. The results suggest that the presence of numerous lysosome-like organelles in the amastigote is a characteristic of the L. mexicana group of parasites.
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PMID:Leishmania mexicana: amastigote hydrolases in unusual lysosomes. 352 61

The intracellular localization of invertase endocytosed by rat liver was investigated by analytical centrifugation in sucrose and Percoll gradients of mitochondrial fractions originating from rats killed 15 h after injection. After isopycnic centrifugation in a sucrose gradient, invertase is located in higher density zones than acid hydrolases. The difference between the distribution of invertase and that of acid hydrolases increases with the amount of invertase injected. When the invertase dose is sufficiently high, a change of lysosomal enzyme distribution is clearly visible. It consists in the shift of a proportion of these enzymes to higher density regions where invertase is located. The proportion of hydrolase activity affected by invertase is different for each enzyme measured; it is the least pronounced for acid phosphatase, and most for acid deoxyribonuclease and arylsulfatase. A pretreatment of the rat with Triton WR 1339 considerably decreases the equilibrium density of structures bearing invertase. Nevertheless invertase distribution is quite distinct from that of the bulk of lysosomal enzymes that are recovered in lower density zones of the gradient; on the other hand the invertase injection to rats treated with Triton WR 1339 causes a spreading of the acid hydrolase distribution towards higher density zones. The distribution of acid hydrolases and invertase in a Percoll gradient depends on the sucrose concentration of the solvent. It is shifted towards higher densities when the sucrose concentration increases. The phenomenon is more important for invertase. These results are best explained by supposing that invertase accumulates in a distinct population of lysosomes that can be individualized as a result of the density increase they are subjected to by the invertase they accumulate. It is proposed that these lysosomes mainly originate from non-parenchymal cells of the liver.
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PMID:Effect on lysosomes of invertase endocytosed by rat-liver. 402 43

We have examined the effect of chloroquine on rat liver lysosomal enzyme distributions after isopycnic centrifugation in a sucrose gradient. Chloroquine injection causes the large majority of cathepsin C, acid phosphatase and N acetyl glucosaminidase to migrate towards lower density regions; on the other hand only about 50% of arylsulfatase and acid deoxyribonuclease are subjected to such a density shift. To specifically mark hepatocyte lysosomes and sinusoidal cell lysosomes, rats were injected with galactosylated bovine serum albumin (A) or mannosylated bovine serum albumin (B) labelled with 125I tyramine cellobiose; A is selectively endocytosed by hepatocytes, B by sinusoidal cells. The radioactivity distribution is affected by chloroquine in the same way as cathepsin C, after injection of A though it is not influenced by chloroquine after the injection of B. These results show that chloroquine does not modify the density of liver sinusoidal cell lysosomes when it decreases the density of hepatocyte lysosomes. Such a difference could result from the fact that sinusoidal cell lysosomes do not accumulate chloroquine to the same extent as hepatocyte lysosomes. Chloroquine treatment could be useful to distinguish between hepatocyte lysosomes and sinusoidal cell lysosomes.
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PMID:Chloroquine allows to distinguish between hepatocyte lysosomes and sinusoidal cell lysosomes. 843 31

The contents of selected hydrolytic enzymes of oil-induced peritoneal, normal alveolar, and BCG-induced alveolar macrophages have been studied. On a per cell or nitrogen basis the normal alveolar cells contained considerably more acid phosphatase, cathepsin, acid ribonuclease, lysozyme, and lipase than peritoneal cells. The BCG-induced alveolar macrophage exhibited increased levels of acid phosphatase, lysozyme, and lipase as compared to alveolar macrophages from unstimulated rabbits. The morphological differences between these cells was discussed and electron micrographs of the BCG-induced macrophage presented. Fractionation of the BCG-induced macrophage by differential centrifugation showed that 60 to 80 per cent of the total cell content of acid phosphatase, cathepsin, beta glucuronidase, acid ribonuclease, acid deoxyribonuclease, aryl sulfatase, lysozyme, and lipase were localized in a postnuclear fraction which sedimented at 15,000 g. This fraction also contained the majority of the mitochondria as evidenced by its content of cytochrome oxidase. Non-specific esterase was not localized to this fraction. A separation of the hydrolase-containing particles and mitochondria was achieved by isopycnic sucrose gradient centrifugation. Under the conditions employed, the mitochondria distributed at densities of 1.19 to 1.20, whereas the hydrolase particles sedimented to a density of 1.26 to 1.27. Each of the hydrolases including acid phosphatase, beta glucuronidase, cathepsin, lysozyme, and acid ribonuclease exhibited maximum activities in the same gradient fraction. The isolated granules exhibited enzymatic latency, and activation could be achieved by cycles of freezing and thawing or surface active agents. The majority of each of the hydrolytic enzymes could be liberated in a non-particulate form by mechanical trauma. Macrophages which had been stained supravitally with neutral red were fractionated by differential and gradient centrifugation. More than 70 per cent of the dye could be recovered in the particulate hydrolase fraction. The isolated, stained granules resembled those seen in the intact cell.
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PMID:THE PARTICULATE HYDROLASES OF MACROPHAGES. I. COMPARATIVE ENZYMOLOGY, ISOLATION, AND PROPERTIES. 1411 77