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)

Primate liver lysosomal acid DNase is an endonucleolytic enzyme. The enzyme has both 3'- and 5'-nucleotidohydrolase activities. The oligonucleotides produced by DNase are polymers mainly about 30 mononucleotides long. The Arrhenius plot shows a discontinuity with a transition temperature at 47 degrees C, with an activation energy of 107 kJ/mol below and 67 kJ/mol above this temperature. The activation enthalpy is 104 kJ/mol and the entropy -0.498 kJ/mol/K. The enzyme is subject to substrate inhibition and the Km value is 159 X 10(-3) mM DNA-P.
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PMID:Lysosomal acid deoxyribonuclease from vervet monkey livers--II. Enzymic properties. 653 8

Acid and neutral deoxyribonucleases (DNases) of the cow snout epidermis were investigated by the microdisc-electrophoresis of polyacrylamide gels containing highly polymerized DNA and by isoelectric focusing techniques. The nucleases were characterized with respect to their pH optimum. An acid DNase at pH 5.0 was detected as a single distinct band after the electrophoretic separation. After isoelectric focussing also, only one acid DNase activity with an isoelectric point (IP) of 6.2 was detectable. Neutral DNases at pH 7.4 were demonstrated as major and minor bands by their different electrophoretic mobilities. In the isoelectric focusing system also, two neutral DNases, a major one (IP, 4.6) and a minor one (IP, 6.4), were found. Characterization with respect to their histologic location showed acid and neutral DNases across the epidermal layers with the highest activities in the upper layers, where DNA concentration had been shown to be lowest. In correlation with their subcellular distribution, the highest activities of both acid and neutral DNase were found in the 105,00 X g supernatant of the subcellular fractions.
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PMID:Microdisc-electrophoretic study of deoxyribonucleases in cow snout epidermis. 662 44

Adrenaline (10-6 g/ml) and insulin (10-6-8 IE/ml) cause changes of the acid DNase and phosphatase activity in hepatic cells of rat embryos on the 20th day of development. Adrenaline stimulates granular endoplasmatic reticulum development, increases the number and size of lysosomes, breaks their integrity. Insulin practically has no effect on the DNase activity, but labilizes the lysosome membrane.
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PMID:[Characteristics of the reaction of the embryonic hepatocyte to the effect of insulin and adrenaline]. 702 32

The levels of Acid and Alkaline DNases were measured in the serum of patients with: (a) Cancer of the Genitourinary Tract (confirmed by biopsy), (b) with inflammatory diseases and non-malignant tumours of the Genitourinary tract, (c) healthy blood donors. In the first group the results showed that the Acid DNase level was raised in 62% and Alkaline DNase in 43%. In the second group acid DNase was increased in 30% and Alkaline DNase in 13%. In the third group Acid and Alkaline DNase levels were normal. These results suggest that the measurement of Acid and Alkaline DNases could be considered as malignant diseases markers, in spite of false positive and false negative results in some cases.
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PMID:The role of acid and alkaline DNases as tumour markers in cancer of the genitourinary tract. 711 81

Some lysosomal enzymes (viz., acid DNase, acid RNase and beta-glucuronidase) were estimated in different parts of the rabbit Fallopian tube during different hours post coitum (p. c.). At estrus, alterations of acid RNase and beta-glucuronidase were observed in different anatomical segments of the Fallopian tube but acid DNase was undetectable. When these enzymes were compared at different hours p.c., it was noticed that when the ovum reaches ampullary (A), ampullary-isthmic junction (AIJ) and isthmic (I) segments of the Fallopian tube at the respective hours 14, 24 and 70, the acid DNase activity showed increased value in these parts when compared to their preceding groups. Acid RNase also showed similar type of pattern except that it was not altered at 14 hr p. c. At 144 hr p. c. both the enzymes had no significant alteration over 70 hr value, beta-glucuronidase, however, did not show this type of pattern in all the segments till 144 hr p. c. The increased activity of acid RNase and DNase in AIJ and I segments of the tube till 70 hr p. c. suggests the increased lysosomal activity in the tubal fluid produced by secretory cells. The possible involvement of these lysomal factors in the process of fertilization and preparation of ovum prior to implantation is suggested.
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PMID:Variations of lysosomal enzymes in different parts of rabbit Fallopian tube during ovum transport. 722 24

The uptake in vitro was studied of 3H-labeled DNA-anti-DNA complexes by neutrophils and monocytes from human blood. Complexes were prepared from 3H-labeled circular double-stranded (dS) DNA of bacteriophage PM2 and anti-dsDNA-containing sera from patients with systemic lupus erythematosus. After phagocytosis, cells and medium were separated. The cells were treated with DNase to remove adherent and noningested complexes before the cell-associated radioactivity was counted. Thus, only complexes inside the cells were measured. The medium was analyzed for acid-precipitable radioactivity. In this way, we found that neutrophils only phagocytose the complexes, whereas monocytes phagocytose the complexes and degrade the antigen. In contrast, both types of phagocyte degraded the antigen in tetanus-anti-tetanus complexes. The degradation took place after phagocytosis, inside the cells. The difference in DNA degradation between neutrophils and monocytes correlated with the difference in acid DNase activity of the lysosomal fractions: monocytes contained DNase activity, neutrophils did not. With complexes made from DNA with 131I-labeled anti-DNA, we found that both cell types degraded the antibody. Uptake of complexes and degradation of antigen increased with incubation time and cell concentration and was saturable with respect to complex concentration. The processes were inhibited by 5 mM mono-iodoacetic acid or by low temperatures.
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PMID:Phagocytosis and degradation of DNA-anti-DNA complexes by human phagocytes. I. Assay conditions, quantitative aspects and differences between human blood monocytes and neutrophils. 730 85

The characterization of DNase II and DNase I activity was undertaken to discriminate their different roles in physiological nuclear degradation during lens fiber cell differentiation. The activity of both nucleases determined in a new assay allows to discriminate DNase II from DNase I in the same extract. In fibers, both types of nuclease activities are found and appear higher than in epithelial cells. Specific polyclonal antibodies directed against these two nucleases reveal by Western blot analysis the presence of various DNase isoforms. DNase II like-nuclease, present in fibers, is represented by three major bands (60,23, and 18 kDa), which are not detected, at least for two of them (60 and 23 kDa), in epithelial cells. DNase I like-nuclease pattern in fiber cells shows a single 32-kDa band, while several bands can be detected in epithelial cells. Immunocytochemistry studies show both nucleases present in lens cell sections. DNase II is, as usual, in cytoplasm of epithelial cells, but it appears strikingly concentrated in the nuclei of fibers. DNase I is always concentrated in nuclei of epithelial and fiber cells. DNA degradation observed in agarose gels shows that DNase II-activating medium cleaves the DNA from fiber cells more efficiently than DNase I-activating buffer. In addition, DNase II antibody is able to prevent this degradation. These results suggest a specific involvement of DNase II in nuclear degradation during lens cell differentiation.
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PMID:Involvement of DNase II in nuclear degeneration during lens cell differentiation. 749 73

After incubation with DNA human lymphocytes release neutral and acid DNase activities into the culture medium; the release depends on DNA concentration and time of cultivation. The electrophoretic mobility of the released neutral DNase activity is in accordance with DNase I and the electrophoretic mobility of the released acid DNase activity with DNase II. The released DNase activities do not originate from dead cells and are not influenced by blast cell formation. The anesthetic halothane can inhibit the released neutral and acid DNase activities. Inhalation anesthesia can possibly disturb the correlation between DNA and DNases in human blood.
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PMID:Secretion of neutral and acid DNases in cultivated human lymphocytes after incubation with DNA; possible consequences for inhalation anesthesia. 754 35

Deoxyribonucleases from eggs and the liver of Xenopus laevis were partially purified by DEAE-cellulose and heparin-Sepharose affinity column chromatographies. The fractions having egg and liver DNase activities were eluted on high performance liquid chromatography through TSK gel G3000SW at the molecular weights of 41.5 and 45 kDa, respectively. The frog DNases hydrolyzed a native DNA over a heat-denatured DNA, and also formed double-strand cuts not only in linear lambda-DNA but also in closed circular pBR322DNA. The pH optimum of the DNases was 4.5-5.0 in 50 mM acetate buffer. These enzyme activities were abolished by treatment at 80 degrees C for 5 min and pH 2, 3 or 12 for 1 h. The enzymes act in such a manner as deoxyribonuclease II (from bovine spleen)-type nuclease with respect to substrate specificity, optimum pH and cation dependence.
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PMID:[Partial purification and properties of deoxyribonucleases from eggs and liver of Xenopus laevis. Comparison with deoxyribonuclease II from bovine spleen]. 816 69

The sequence preference of a Drosophila lysosomal DNase was studied on the Drosophila hsp 70 heat-shock and histone recombinants, which carry six different genes, and the surrounding spacer sequences. The distribution of cleavage sites was random in respect of the locations of gene and spacer sequences. However, in the presence of 10 mM spermidine, a major transition was observed: the coding sequences became more susceptible than the spacer regions to nuclease attack. A similar transition was induced in the sequence preference of DNase I if the digestion was performed in the presence of spermidine at pH 5.2. At pH 7.5, spermidine does not influence the sequence preference of DNase I, which indicates the involvement of DNA protonation in this transition. In the presence of spermidine, the distributions of preferred and protected sequences were almost indistinguishable for these nucleases, suggesting that the protonated DNA, and not the enzymes, is the target of spermidine. A Drosophila embryonal protein was detected and partially purified which induced the same transition as observed in the presence of spermidine. The purified protein preferentially protected the spacer DNA sequences against acid DNase or DNase I cleavage in the hsp 70 heat-shock and histone gene recombinants. The protection was concentration dependent and occurred only at pH 5.2. The transition of nuclease specificity is probably due to a conformational change in the protonated DNA, induced by the binding of either the embryonal protein or spermidine.
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PMID:Spermidine-induced alteration in the gene-spacer discrimination of nucleases in protonated DNA. 848 53


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