SEARCH · Search PubMed

Results for “DEOXYRIBONUCLEASE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources

PubMed1969

Mycoplasmal deoxyribonuclease activity in virus-infected L-cell cultures.

Cell-free extracts of Mycoplasma hominis and medium from 72-hr broth cultures had deoxyribonuclease activity like that of deoxyribonuclease I. Mg(++) stimulated activity, and the pH optimum was between 8.0 and 9.0. Double-stranded or heatdenatured deoxyribonucleic acid (DNA) served as a substrate, and oligonucleotides were produced. Cell-free extracts of L cells infected with M. hominis or M. hominis plus equine abortion virus (equine herpes virus, EAV) had greatly increased activity over that of extracts of L cells or of L cells infected with EAV alone. In the absence of M. hominis, however, extracts had little activity, most of which was in virus-infected cell cultures. Activity was found in the culture medium only in those systems in which M. hominis was present. It is concluded that M. hominis can contribute significant deoxyribonuclease activity to virus-infected as well as virusfree cell cultures. Perhaps the most interesting question arising concerns the ability of EAV, a DNA virus, to replicate successfully despite the presence of deoxyribonuclease activity at the site of replication (the nucleus).

Cell-Free System↗

PubMed2001

Caspase-3 and caspase-activated deoxyribonuclease are associated with testicular germ cell apoptosis resulting from reduced intratesticular testosterone.

The purpose of the present study was to examine the possible involvement of caspase-3 and caspase-activated deoxyribonuclease in rat testicular germ cell apoptosis resulting from reduced intratesticular testosterone concentration. Adult Sprague Dawley rats received LH-suppressive testosterone- and estradiol-filled SILASTIC capsules of 2.5 and 0.1 cm, respectively, a regimen known to rapidly reduce testosterone production by the testes and to produce azoospermia within 8 wk. Germ cell internucleosomal DNA cleavage increased compared with control levels by 1 wk postimplantation and increased further through 4 wk. In situ terminal deoxynucleotidyltransferase-mediated deoxy-UTP nick end labeling revealed that spermatocytes represented the predominant apoptotic cell type. Modest immunoreactivity for active caspase-3 was localized to the cytoplasm or perinuclear region of the germ cells of control testes. After testosterone and estradiol administration, however, intense staining for caspase-3 was localized to the nuclei of spermatocytes. Western blotting revealed significantly increased caspase-3 cleavage (activation) in nuclei isolated from germ cells after rats were administered testosterone and estradiol. Cleavage of the caspase-3 substrate protein, poly(ADP-ribose) polymerase, was seen after testosterone and estradiol treatment. Additionally, the caspase-activated deoxyribonuclease protein content was significantly increased in germ cells after rats were administered testosterone and estradiol, and caspase-activated deoxyribonuclease immunoreactivity was localized to the nuclei of apoptotic spermatocytes. Taken together, these results indicate that germ cell apoptosis resulting from a reduced intratesticular testosterone concentration is caspase-3 activation dependent and suggest that the translocation of active caspase-3 and caspase-activated deoxyribonuclease to the nucleus may be involved in the induction of germ cell apoptosis.

Animals↗

PubMed1990

Deoxyribonuclease I serum activity in pancreatic cancer.

In patients with pancreatic cancer deoxyribonuclease I (DNase I) serum levels were compared with those of other known pancreatic enzymes. Serum deoxyribonuclease I, elastase 1, immunoreactive trypsin, amylase and phospholipase A2 were determined in 40 healthy controls, 28 patients with pancreatic cancer, 49 with chronic pancreatitis and 40 with extra-pancreatic diseases. The analysis of variance showed a significant difference among groups for serum DNase I values. However, none of the 3 groups of patients had a mean deoxyribonuclease I value higher than that of the healthy controls. In pancreatic cancer and chronic pancreatitis patients, increases in the 4 pancreatic enzymes values were found in percentages that were higher than those for DNase I. A significant correlation was found between DNase I and phospholipase A2, but not between DNase I and elastase 1, immunoreactive trypsin and amylase serum activities. The findings indicate that deoxyribonuclease I serum determination is an even less satisfactory index of pancreatic malignancy than the other pancreatic enzymes. Rather than expressing pancreatic damage, any variations in this enzyme appear more likely to reflect an aspecific phenomenon.

Adult↗

PubMed1975

Extracellular deoxyribonuclease activity of Pseudomonas aeruginosa.

Pseudomonas aeruginosa cultured on deoxyribonucleic acid (DNA) media containing Nissan's heart extract or chicken heart extract could produce extracellular deoxyribonuclease, while on other DNA media with heart extracts from cow, pig and mouse could not. Variation in the kind of peptones in the DNA media did not make significant difference in this activity, although some peptones caused cloudiness of the media. P. aeruginosa did not need cation activators of chloride compounds to produce extracellular deoxyribonuclease. On the modified Eiken's DNA medium, gram negative bacilli other than P. aeruginosa and Serratia marcescens, i.e. Klebsiella, Salmonella, Shigella, Escherichia coli and Alcaligenes did not produce deoxyribonuclease. The production of extracellular deoxyribonuclease activity on the modified Eiken's DNA medium can be used as a supporting test for biochemical identification of P. aeruginosa.

Culture Media↗

PubMed1991

Mechanism of action of deoxyribonuclease II from human lymphoblasts.

Deoxyribonuclease II has been purified through five fractionation steps from the human lymphoblast cell line K562. Isolation included DEAE-cellulose and heparin-agarose chromatography followed by fractionation on Mono-S, Mono-Q and Superose-12 FPLC columns. In an extension of previous studies, deoxyribonuclease II was found to introduce a much higher proportion of single-strand nicks relative to double-strand breaks into supercoiled DNA than has been reported for linear DNA. Application of DNA sequencing techniques has further revealed a unique resistance of 3' termini to hydrolysis by this enzyme. Deoxyribonuclease II cleaves at every available site along the duplexed portion of a paired oligonucleotide substrate with the exception of the last four nucleotides. Consistent with previous results, this deoxyribonuclease II is active at low pH in the absence of Mg2+ and is not inhibited by EDTA, but complete inhibition is observed with 100 microM Fe3+. Likewise we confirmed the presence of 3'-phosphoryl termini on the DNA cleavage products since they failed to function as primers for DNA synthesis catalyzed by Escherichia coli DNA polymerase I.

Base Sequence↗

PubMed1982

Dimerization of deoxyribonuclease I, lysozyme and papain. Effects of ionic strength on enzymic activity.

Transition of bovine ribonuclease A from its monomeric to a dimeric form changes the pattern of enzymic activity response to ionic strength [Sorrentino, S., Carsana, A., Furia, A., Doskocil, J., and Libonati, M. (1980) Biochim. Biophys. Acta. 609, 40-52]. To see whether this phenomenon could be common to other enzyme-substrate systems, the action of various dimeric and monomeric enzymes (ox pancreas deoxyribonuclease, hog spleen acid deoxyribonuclease, bovine seminal ribonuclease, egg-white lysozyme, and papain) on polyelectrolytic substrates has been studied under different conditions of ionic strength. Dimerization of ox pancreas deoxyribonuclease, lysozyme and papain was obtained by cross-linkage with dimethyl suberimidate. The main results of the investigation, similar to those obtained with ribonuclease A, are the following. 1. Enzyme monomers and dimers show markedly different patterns of activity response to ionic strength at given pH values: the reactions catalyzed by monomeric enzymes are highly modulated by salt, whereas those catalyzed by dimeric enzymes are not. In particular, at the reaction optimum the monomeric form of an enzyme is significantly more active than the dimeric one. 2. The optimum of the reaction catalyzed by a dimeric enzyme is shifted to higher ionic strengths in comparison with that of the reaction catalyzed by a monomeric enzyme. A model is proposed that could explain these results on the basis of the influence of ionic strength on the intramolecular dynamics of the enzyme molecule and its non-specific interactions with polyelectrolytic substrates.

Animals↗

PubMed1979

Herpes simplex virus DNA polymerase, thymidine kinase and deoxyribonuclease activities in cells infected with wild type, ultraviolet-irradiated and defective virus.

The DNA polymerase, thymidine kinase and deoxyribonuclease activities were studied in cells infected with wild type (wt), ultraviolet (UV)-irradiated and defective herpes simplex virus type 1. All three enzymatic activities were expressed in cells infected with wt virus. In cells infected with UV-irradiated virus, the thymidine kinase and deoxyribonuclease activities were inhibited and the DNA polymerase activity was markedly suppressed. In cells producing defective virus, there was thymidine kinase activity, but the viral deoxyribonuclease activity was considerably reduced. The DNA polymerase activity was fully expressed in cells producing defective virus at passage level 5, but at passage level 6, the activity of the viral DNA polymerase declined.

Animals↗

PubMed2002

Expression of caspase-activated deoxyribonuclease (CAD) and caspase 3 (CPP32) in the hydropic cochlea of guinea pigs - second report.

Apoptosis was induced in the cochlea by the injection of keyhole limpet hemocyanin (KLH) into the endolymphatic sac of guinea pigs and immunohistochemically examined. Keyhole limpet hemocyanin was injected into the right endolymphatic sac. The temporal bones were fixed via cardiac infusion of fixative and immunohistochemically stained for caspase-activated deoxyribonuclease or caspase 3. Endolymphatic hydrops became evident in the cochlea 1 day after the injection of keyhole limpet hemocyanin (n=6). The temporal bones in the control group did not show any caspase-activated deoxyribonuclease or caspase 3 immunoreactivity (n=6). Immunoreactivity for caspase 3 was detected in the supporting cells of the organ of Corti, the stria vascularis and the spiral ganglion cells. Caspase-activated deoxyribonuclease was also detected in the same areas. These findings suggest that apoptosis is involved in the pathogenesis of endolymphatic hydrops. This phenomenon could lead to cochlear dysfunction, as seen in endolymphatic hydrops.

Adjuvants, Immunologic↗

PubMed1977

An adenosine triphosphate-dependent deoxyribonuclease from Alcaligenes faecalis.

A deoxyribonuclease was purified approx. 800-fold from crude extracts of the bacterium Alcaligenes faecalis. The enzyme requires ATP and Mn2+; ATP could be replaced by any other ribo- or deoxyribo-nucleoside triphosphate, and Mn2+ could be replaced by Mg2+ in 0.1 M-Tris/HCl, pH 8.0 at 37 degrees C. The enzyme could degrade linear duplex or denaturated DNA, but was inactive with closed-circular duplex DNA from bacteriophase PM-2. In the course of nucleolytic activity, ATP was hydrolysed. We have measured deoxyribonuclease and adenoxine triphosphatase activity in the presence of various salts, and found that the amount of ATP hydrolysis associated with a given amount of deoxyribonuclease activity was decreased in the presence of tetraethylammonium ions. Since these ions decrease the stability of the DNA helix, we conclude that one function of the ATP hydrolysis is to unwind the DNA.

Adenosine Triphosphatases↗

PubMed1974

A demonstration of several deoxyribonuclease activities in mammalian cell mitochondria.

Extracts of purified mitochondria from adult rabbit liver and kidney have been prepared by lysis with Triton X-100. Such extracts contain deoxyribonuclease activity demonstrable at alkaline pH. Studies utilizing the effects of substrate variation, differing ionic strength, nucleoside di- and triphosphates, and SH-group inhibitors reveal the existence of at least five distinguishable deoxyribonuclease activities in these extracts. Assay of lysosomal and mitochondrial enzyme markers indicates no significant lysosomal contamination of the mitochondrial extracts. Further studies also suggest that the alkaline deoxyribonuclease activity is specifically located in or in association with mitochondria.

Acid Phosphatase↗

PubMed1976

A DNA polymerase from Ustilago maydis. 2. Properties of the associated deoxyribonuclease activity.

The polymerase and deoxyribonuclease activities of the purified Ustilago maydis DNA polymerase coeluted from a hydroxyapatite column, cosedimented in sucrose gradients in both the absence and presence of salt, possessed similar thermolabilities and reaction requirements. These observations suggest that both activities are associated with the same enzyme and that the deoxyribonuclease activity is not a contaminant. The initial rate of degradation of native 3'-end-group-labelled DNA was similar to that of a heat-denatured substrate, but the final extent was greater for the former. The enzyme exhibits a high specificity for degradation of DNA in a 3' leads to 5' direction. The degradation of a DNA template was inhibited by the presence of the deoxyribonucleoside triphosphates necessary for simultaneous DNA synthesis, but not that of the newly synthesised DNA. About 50%, 29% and 13% of the purine, cytosine and thymine deoxyribonucleotide residues incorporated by the enzyme into DNA respectively, were subsequently excised when monitored by the resulting conversion of the triphosphate substrates to free monophosphate. The majority of the purine deoxyribonucleoside monophosphates appear after the synthetic phase of the reaction has ceased. In many respects, therefore, the deoxyribonuclease activity of the U. maydis DNA polymerase is similar to the bacteriophage T4-induced enzyme.

Basidiomycota↗

PubMed1974

Extracellular deoxyribonuclease production by anaerobic bacteria.

The production of extracellular deoxyribonuclease was examined with anaerobic organisms isolated from clinical specimens. Nuclease activity was extraordinarily common. All strains of Fusobacterium, including eight species, as well as Bacteroides fragilis and B. melaninogenicus, displayed enzyme activity. Whereas the gram-positive bacteria were generally less productive, all strains of Clostridium perfringens, Peptostreptococcus intermedius, and P. anaerobius specifically produced deoxyribonuclease. The test is taxonomically valuable, particularly in the characterization of gram-positive cocci, since a deoxyribonuclease-producing coccus indicates P. intermedius or P. anaerobius. Additionally, possession of the enzyme may prove to be a useful correlate of the potential pathogenicity of anaerobes.

Anaerobiosis↗

PubMed1962

Simplified antistreptococcal deoxyribonuclease assay.

Olitzky, Irving (Bio-Science Laboratories, Los Angeles, Calif.), Sam Berkman, and Doris Bass. Simplified antistreptococcal deoxyribonuclease assay. J. Bacteriol. 84:1011-1015. 1962.-A simple antistreptococcal deoxyribonuclease assay has been devised in which dilutions of the patient's serum are reacted with deoxyribonuclease, and residual active enzyme is then detected by the Di Salvo technique using commercially available agar medium containing deoxyribonucleic acid. Use of this test as supplemental to antistreptolysin-O titrations leads to increased positive findings when searching for streptococcal antibodies.

Antibodies, Bacterial↗

PubMed1980

Extremely high titers of serum antibodies against the streptococcal exoenzyme deoxyribonuclease B.

In sera from 4 of 25,000 individuals tested for antibodies against streptococci, extremely high antideoxyribonuclease B titers ( > 10(6) U/ml) were found. Two of the cases were diagnosed as monoclonal gammopathies. The M-components were shown to possess the anti-deoxyribonuclease B activity. The other two cases were diagnosed as relapsing erysipelas. The high serum titers of deoxyribonuclease B antibodies were accompanied by a very inflammatory reactivity in the patients' sera and by an oligopolyclonal pattern of immunoglobulin G. In routine diagnoses of streptococcal infections with the anti-deoxyribonuclease B test, patients with extremely high serum titers should be examined for the possible occurrence of gammopathies.

Adult↗

PubMed1986

Carryover of preformed staphylococcal enterotoxins and thermostable deoxyribonuclease from raw cow milk to Khoa--a heat-concentrated Indian milk product.

Preformation of enterotoxins and thermostable deoxyribonuclease by Staphylococcus aureus in raw cow milk and their carryover to Khoa--a heat-concentrated (98 degrees C for 15 to 20 min) Indian milk product--was evaluated. Detectable enterotoxins and deoxyribonuclease, as evidenced in the zone diameters of 10 to 16 mm, were performed in 10 h incubation of milk samples inoculated with strains of Staphylococcus aureus at 1 X 10(6) cfu/ml of milk. Both preformed enterotoxins and thermostable deoxyribonuclease were carried over to Khoa from raw milk. The study implies the use of good quality raw milk free from pathogenic organisms for preparation of milk products such as Khoa.

Animals↗

PubMedDate not supplied

[Different deoxyribonuclease-activities in bull seminal plasma (author's transl)].

By means of the in situ assay of deoxyribonucleases in DNA-containing polyacrylamide gels after separation by micro-disc-electrophoresis different deoxyribonucleases are detectable in bull seminal plasma. There are two groups of acid deoxyribonuclease-activities with a pH optimum at pH 5.0, one with a pH optimum at pH 7.4 and an additional one with a pH optimum at pH 8.5.

Animals↗

PubMed1981

Serum alkaline deoxyribonuclease in oral cancer and premalignant lesions.

Serum activities of alkaline deoxyribonuclease were assayed in 61 patients with oral squamous cell carcinoma, 23 with oral keratosis (a possible premalignant lesion), and 48 matched controls. The activity of alkaline deoxyribonuclease was significantly greater in patients with oral cancer than in either those with oral keratosis, or controls. The activities of deoxyribonucleases in keratosis were greater than in controls but not at a significant difference.

Carcinoma, Squamous Cell↗

PubMed1980

[Effect of carbon and nitrogen sources on the deoxyribonuclease activity of actinomycetes (author's transl)].

The amount of the deoxyribonucleases produced by several Actinomyces species in a fluid medium varies considerably, depending on the type of the carbon and nitrogen sources added to the medium. Starch effects the enzyme biosynthesis most favourably of all tested carbon sources. The nitrates are more suitable as nitrogen sources than the ammonia compounds. Highest biosynthesis of deoxyribonucleases is observed on media containing organic nitrogen. Nutrient medium of optimum content may be found for each producer, ensuring maximum biosynthesis of deoxyribonucleases.

Actinomyces↗