Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.1.21.3 (deoxyribonuclease)
1,528 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The level of the non--sedimentating activity of acid hydrolases (deoxyribonuclease, phosphatase, cathepsins) and electron microscopy of lysosomes has been studied after freezing to --30 degrees, --70 degrees, --140 degrees and --196 degrees. It has been found that enzyme solubilistion and lysosome ultrastructure distortion are mostly marked in the temperature range between 0 degrees and --30 degrees C. Additional membrane damage is observed in the temperature range from --140 degrees to --196 degrees C. It is suggested that not only physico-chemical changes during phase transitions of free water in the freezing medium but also recrystallization processes and the freezing-out of water structurally bound with membranes may contribute to mechanism of lysosome cryoinjury.
...
PMID:[Effect of deep freezing on isolated rat liver lysosomes]. 20 67

Spleen lymphocytes of BCG-immunized mice contain a soluble factor that inhibits in vitro the growth of the H37Rv strain of Mycobacterium tuberculosis within normal peritoneal macrophages. The water-soluble extracts of sensitized lymphocytes, disrupted by freezing and thawing, although less active than the corresponding viable cells retained a significant growth-inhibiting activity. Dialysis against distilled water, lyophilization, exposure to ribonuclease and deoxyribonuclease, and storage at -20 degrees C of the water-soluble extracts did not affect their antimycobacterial activity, whereas extracts heated at 100 degrees C were completely devoid of such an activity. All the inhibiting activity was recovered in the void volume of the column after chromatography on Sephadex G-200. Water-soluble constitutents of sensitized lymphocytes did not affect BCG grown in vitro, and on repeated treatments of tuberculous mice they led to a negligible protection against pulmonary tuberculosis. Preliminary observations seem to indicate that other soluble factors in lymphocytes of BCG-sensitized mice have the capacity to potentiate in vitro the phagocytic activity of normal macrophages.
...
PMID:Partial characterization of a factor extracted from sensitized lymphocytes that inhibits the growth of Mycobacterium tuberculosis within macrophages in vitro. 82 9

During bacteriophage studies on Haemophilus influenzer, it was observed that encapsulated type b and unencapsulated Rb strains released a bactericidal substance acitve against types a, c, d, e, and f H. influenzae, non-typable H. influenzae strains, other Haemophilus species, and certain members of the Enterobacteriaceae. The bactericidal activity was assayed by a plaque test utilizing an Rd strain as an indicator lawn and was also demonstrated in mixed broth cultures of a producer strain and an indicator strain. Immediately lysis of sensitive bacteria by the factor was not evident. The factor is sensitive to trypsin but resistant to deoxyribonuclease, treatment with 2-mercaptoethanol, lipase, alpha-amylase, and heating in a 100 degrees C water bath for 20 min. The activity is not dependent upon increased Ca2+ or Mg2+ concentration as is necessary for HP1C1 and S2 phage propagation. The bactericidal factor is not pelleted by high-speed centrifugation at 150,000 X g for 6 h. Treatment with ultraviolet light or mitomycin C does not result in observable phage, phage-like particles, or increased bactericidal activity. T-HE BACTERICIDAL FACTOR IS NOT A TYPICAL SMALL MOLECULAR WEIGHT "COLICIN-LIKE" BACTERiocin in that it is not inducible, has a wider range of activity, and does not kill by "single-hit" kinetics. On preliminary characterization, it is a thermostable protein toxic to certain bacterial strains.
...
PMID:Bactericidal substance produced by Haemophilus influenzae b. 108 28

For simultaneous cytophotometric measurement of DNA and RNA, the standardized Methyl Green-Pyronin Y technique is an obvious choice. It is, however, first necessary to correlate the uptake of Pyronin Y to the staining intensity of RNA. The material consisted of paraffin sections of formalin- or Carnoy-fixed rat liver. The sections were pretreated with water, buffer, deoxyribonuclease, ribonuclease, or both enzymes in sequence, and stained with the standardized Methyl Green-Pyronin Y procedure, Gallocyanin chromalum, or the Feulgen reaction. Sections stained directly without pretreatment served as controls. Staining intensities were measured with an image analyser for cell nuclei, nucleoli and cytoplasm. After deoxyribonuclease treatment, nuclear staining intensity with Methyl Green, Gallocyanin chromalum, and Schiff's reagent dropped nearly to zero. The same was seen for both nucleoli and cytoplasm with Pyronin Y and Gallocyanin chromalum after ribonuclease treatment. Staining intensity of Pyronin Y correlated directly with that of Gallocyanin chromalum for nucleoli and cytoplasm. After ribonuclease treatment, a direct correlation was found between the nuclear staining intensity of Methyl Green and nuclear absorption of Gallocyanin chromalum. We conclude that the standardized Methyl Green-Pyronin Y stain is reliable for the simultaneous quantitative assessment of both RNA and DNA. The simplicity of this technique makes it a valuable tool even for daily routine.
...
PMID:Simultaneous quantification of DNA and RNA in tissue sections. A comparative analysis of the methyl green-pyronin technique with the gallocyanin chromalum and Feulgen procedures using image cytometry. 137 24

Replacement of the amino-terminal 40-amino-acid region of the 588-amino-acid precursor of the membrane-bound penicillin-binding protein 3 (PBP3) by the decapeptide MKGKEFQAWI was carried out by altering the amino-coding end of the ftsI gene. Insertion of the modified gene into a runaway-replication plasmid under the control of a fused lpp promoter and lac promoter/operator, resulted in the overexpression by Escherichia coli of the modified PBP3 (designated PBP3**) in the cytoplasm. About 80% of the accumulated PBP3** underwent sequestration in the form of insoluble protein granules that were isolated by cell breakage or cell lysis. After selective removal of contaminants by an EDTA-lysozyme/DNase (deoxyribonuclease)/Nonidet extraction, treatment of the granules with guanidinium chloride followed by dialysis against buffer containing 0.5 M NaCl yielded a refolded, water-soluble PBP3**, which, upon chromatography on Superose 12, exhibited the expected 60,000 molecular mass. The refolded PBP3** bound benzylpenicillin in a 1 to 1 molar ratio, was highly sensitive to aztreonam and showed the same degree of thermostability, in terms of penicillin-binding capacity, as the parent, membrane-bound PBP3, suggesting that protein refolding occurred with formation of the correct intramolecular interactions. Two to three mg of refolded PBP3** can be obtained from 1 litre of culture of the overproducing strain.
...
PMID:Overexpression, solubilization and refolding of a genetically engineered derivative of the penicillin-binding protein 3 of Escherichia coli K12. 305 Mar 60

Bullous pemphigoid (BP) antibodies are known to react with an antigen of the basement membrane zone (BMZ) of squamous epithelia and produce, by the indirect immunofluorescence technique, linear fluorescence at the BMZ. Direct and indirect immunoelectron microscopy (IEM) have demonstrated BP antigen to be within the lamina lucida, in close association with the basal cell membrane. Trypsin-dissociated epidermal basal cells bind BP antibodies in a polar distribution, presumably because the BP antigen is restricted to the dermal pole of the basal cell membrane. In this study we have utilized newborn BALB/c mouse skin to obtain both dissociated basal cells (by trypsinization) and epidermal sheets (by dithiothreitol treatment). We show that viable basal cells, which are impermeable to IgG molecules, do not react with BP antibodies. When the basal cell plasma membrane is disrupted by cytospin centrifugation, air drying, freezing and thawing, or hypotonic lysis, or permeated by nonionic detergents (saponin), cells become reactive with BP antibodies. Basal cell cytoskeletons, prepared by sequential treatment with Triton X-100, deoxyribonuclease, and 2 M NaCl continue to react with BP antibodies. Similarly, viable epidermal sheets fail to bind BP antibodies. When epidermal sheets are treated with nonionic detergents, water, or freezing and thawing prior to incubation with BP antibodies, linear BMZ fluorescence is observed. IEM study of saponin-treated basal cells shows the immunoreactants to be localized on intracytoplasmic vacuoles which represent internalized hemidesmosomes. IEM of permeated epidermal sheets shows the immunoreactants as aggregates on the inner surface of the dermal pole of the basal cell membrane. These observations suggest that the BP antigen is intracellular and is in close association with the basal cell cytoskeleton and hemidesmosomes.
...
PMID:A pool of bullous pemphigoid antigen(s) is intracellular and associated with the basal cell cytoskeleton-hemidesmosome complex. 388 Jul 96

A lipopolysaccharide (LPS) fraction was extracted from Nichols, nonpathogenic Treponema pallidum by the hot, phenol-water procedure. The LPS was freed of nucleic acids and water-soluble proteins by successive exposures to ribonuclease, deoxyribonuclease, and Pronase. Purified LPS responded positively in a colorimetric assay for lipopolysaccharide. Electron microscope examination of the LPS both before and after purification demonstrated a heterogeneous mixture of forms including spheres, doughnuts, and ribbons. The trilaminar nature of the ribbon forms was observed by both negative staining and thin sectioning. Lyophilization of the LPS caused an increase in the number and length of ribbon forms seen. Results suggest that the surface layers of treponemes are similar to those of gram-negative bacteria.
...
PMID:Ultrastructure of lipopolysaccharide isolated from Treponema pallidum. 412 67

Serratia marcescens was isolated on a new medium-commercial deoxyribonuclease agar with the addition of cephalothin (1,000 mug/ml) and Toluidine Blue (1,000 mug/ml). It was detected in water samples even though it comprised only 0.1 to 0.0001% of the total bacterial population.
...
PMID:Isolation of Serratia marcescens on deoxyribonuclease-toluidine blue-cephalothin agar. 456 85

Ribosomal preparations obtained from Salmonella typhimurium by differential centrifugation and sodium dodecyl sulfate (SDS) treatment of the bacillary lysate were found to be immunogenic in F(1) hybrid (C(3)H/HeJ x DBA/2J) and albino Swiss mice, as determined by progressive host survival. The immunity obtained was independent of the need for adjuvant and dependent on the dosage of immunogen given. Immunizations with the ribosomal preparations induced an immune response comparable to that obtained by vaccination with living organisms and significantly greater than that obtained by immunization with heat-killed salmonellae, purified lipopolysaccharide, or crude and SDS-treated endotoxin preparations. No effect on the immunogenicity of the ribosomal fraction was observed by enzymatic treatment with trypsin, Pronase, deoxyribonuclease, and pancreatic ribonuclease. Linear sucrose density gradient resolution of the preparations showed that the immunogenicity of the ribosomal fraction was not unique to any one of its subcomponents. Ethyl alcohol-precipitated, crude ribonucleic acid preparations obtained from the ribosomal and sucrose density-resolved ribosomal preparations were found to induce an immune response comparable to that obtained by immunization with the entire ribosomal fraction. Dialysis in doubly distilled demineralized water slightly reduced the immunogenicity of the preparation; however, comparable dialysis in 10(-4)m MgCl(2)-phosphate buffer did not. Chemical assays of the preparations found to be immunogenic were performed.
...
PMID:Isolation and partial characterization of an immunogenic moiety obtained from Salmonella typhimurium. 489 82

Aldehyde-fixed rat tissues were variously dehydrated and impregnated in water-miscible 2-hydroxypropyl methacrylate (HPMA) containing 3 to 20 per cent water and 0.1 per cent alpha,alpha-azobisisobutyronitrile as catalyst for subsequent polymerization with ultraviolet light. Heat polymerization was also effective. Blocks of embedded tissue readily gave ultrathin sections, which required staining by uranyl acetate and/or lead stains to give adequate contrast for electron microscopy. The ultrastructure of pancreas, kidney, muscle, and intestine was well preserved by aldehyde fixation alone. Use of postfixation in osmium tetroxide or direct osmium tetroxide fixation was unsatisfactory. The fine structure of aldehyde-fixed liver from fasted rats was well preserved, whereas that from normal rats showed considerable disorganization and collapse, apparently because of extraction of glycogen during the embedding procedure. Enzymatic extraction of proteins by pepsin and of ribonucleic acid by ribonuclease after either formaldehyde or glutaraldehyde fixation was rapidly effected by direct treatment of ultrathin sections with solutions of the enzymes. In contrast, no digestion of chromatin by deoxyribonuclease could be detected. In spite of this present limitation, HPMA appears to have several advantages over earlier water-miscible embedding media for electron microscopy and to be particularly suitable for ultrastructural cytochemistry.
...
PMID:Hydroxypropyl methacrylate, a new water-miscible embedding medium for electron microscopy. 585 16


1 2 Next >>

---