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

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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)

Dialyzable Lawrence-type transfer factor was prepared from the spleen cells of CF1 mice inoculated with Coccidioides immitis- and Candida albicans-killed vaccines and with live Mycobacterium tuberculosis vaccine (BCG). These preparations were shown to transfer antigen-specific cell-mediated immunity to naive mice, as measured by the delayed skin test and footpad-swelling methods. Reactivity could be demonstrated when the test antigens were given 24 h after the transfer factor, but not when they were given simultaneously. Coccidioides-specific transfer factor was shown to be sensitive to Pronase and resistant to trypsin and ribonuclease. A preparation of BCG transfer factor was sensitive to snake venom phosphodiesterase.
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PMID:Transfer of delayed hypersensitivity in mice to microbial antigens with dialyzable transfer factor. 6 30

Serological investigations are carried out on hyperimmune rabbit and guinea pig sera with two antigens each of Mycobacterium tuberculosis H37Rv, Mycobacterium bovinus, Mycobacterium avium and Mycobacterium Kanzassi. One of the antigens is obtained through electrohydraulic destruction of delipidated mycobacteria, while the other constitutes cell walls, purified with ribonuclease, of non-delipidated mycobacterial cells, destroyed by the same method. The antigens, prepared by the electrohydraulic method, possess a markedly expressed complement-fixing capacity, conversely to the antigen from cell walls, which is slightly active in complement-fixation tests. Again a trend is observed towards a possible serological indentification of the species of mycobacteria that have caused the immune transformation of the major organism; yet the questions still remain to be settled. The immunogenes used possess a high activity and induce high titre antisera, established also in other investigations, which make reasonable their study as vaccines.
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PMID:[Experiments for the serological establishment of the species of mycobacteria inducing an immune restructuring of the macroorganism]. 8 60

The bacteriocin produced by Mycobacterium smegmatis ATCC 14468 was isolated, and a study was made of its chemical, physical, and biological properties. No appreciable bacteriocin activity was found in the culture supernatant fluids, but it was released in appreciable quantities after disruption of the cells. The material was purified 49-fold by means of chromatography on diethylaminoethyl-cellulose, ammonium sulfate fractionation, gel filtration on Sephadex G-200, and chromatography on diethylaminoethyl-Sephadex A-50. Its molecular weight was determined to be approximately 75,000 from the elution profile on Sephadex G-200 chromatography. The bacteriocin was resistant to deoxyribonuclease, ribonuclease, lipase, ultraviolet irradiation, and freeze-thawing, whereas it was relatively less thermostable and was sensitive to proteolytic enzymes. The lethal effect of the bacteriocin was demonstrated by the decrease in viable counts of the bacteriocin-sensitive indicator strain, M. diernhoferi ATCC 19340. The bacteriocin preparation inhibited the growth of HeLa-S3 cells.
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PMID:Purification, properties, and cytotoxic effect of a bacteriocin from Mycobacterium smegmatis. 46 82

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.
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PMID:Partial characterization of a factor extracted from sensitized lymphocytes that inhibits the growth of Mycobacterium tuberculosis within macrophages in vitro. 82 9

Youmans, Anne S. (Northwestern University Medical School, Chicago, Ill.), and Guy P. Youmans. Effect of trypsin and ribonuclease on the immunogenic activity of ribosomes and ribonucleic acid isolated from Myobacterium tuberculosis. J. Bacteriol. 91:2146-2154. 1966.-The ribosomal fraction of the attenuated strain, H37Ra, of Mycobacterium tuberculosis was treated with trypsin alone, ethylenediaminetetraacetic acid (EDTA) alone, EDTA and pancreatic ribonuclease, or with trypsin and ribonuclease. After each of these treatments, the ribosomal fractions were injected intraperitoneally into male CF-1 mice to test their capacity to produce an immune response to infection with virulent tubercle bacilli, strain H37Rv. Removal of protein with trypsin left the immunogenicity unchanged; EDTA alone reduced immunogenicity in the smaller vaccinating doses; EDTA plus ribonuclease reduced the immunogenicity by approximately 50% in the highest (1.0 mg) vaccinating dose; ribonuclease alone, after treatment with trypsin, reduced immunogenicity also approximately 50%. A crude mycobacterial ribonucleic acid (RNA) was prepared by extraction of the ribosomal fraction with alcohol. This RNA preparation was as effective in producing an immune response as the ribosomal fraction from which it was prepared, unless the RNA was partially or completely degraded during the preparation. The effect of ribonuclease on the immunogenicity of the RNA was similar to that obtained with the ribosomal fractions, except that ribonuclease completely destroyed the immunogenicity of a partially degraded RNA. RNA appears to be an essential part of an immunizing substance in attenuated tubercle bacilli, which produces a high degree of immunity in mice; 50 mug (dry weight) will protect approximately 80% of the mice, and as little as 0.5 mug will protect approximately 30% of the mice. Mycobacterial RNA not incorporated in Freund's incomplete adjuvant was nonimmunogenic. Yeast RNA incorporated in Freund's incomplete adjuvant was not immunogenic.
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PMID:Effect of trypsin and ribonuclease on the immunogenic activity of ribosomes and ribonucleic acid isolated from Mycobacterium tuberculosis. 495 10

The amount of ribonucleic acid (RNA), protein, and deoxyribonucleic acid (DNA) was determined in pellicle cultures of different ages of the H37Ra strain of Mycobacterium tuberculosis, grown on a synthetic medium. We found that the highest content of RNA and protein was present in 2-week-old cultures, indicating that these cells were in the logarithmic phase of growth. DNA content was highest at 1 and 2 weeks. The amount of all three compounds then decreased about 50% during the following 6 weeks. Two-week-old cells should therefore be used for preparation of the immunogenic ribosomal fraction. The optimal concentration of zinc chloride increased RNA and protein synthesis, and also improved the appearance of the pellicle growth. Two-week-old cells, which contained the largest amount of RNA and protein, immunized mice significantly better than older cells. Since protein and DNA are not involved in the production of immunity, a correlation could be made between amount of RNA and the capacity of viable H37Ra cells to immunize mice. The immunizing capacity of these cells was not affected by ribonuclease, probably because the ribonuclease did not penetrate into the whole cells.
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PMID:Ribonucleic acid, deoxyribonucleic acid, and protein content of cells of different ages of Mycobacterium tuberculosis and the ralationship to immunogenicity. 496 39

By following careful procedures, mycobacterial ribosomal fractions and ribonucleic acid (RNA) prepared by ethyl alcohol precipitation were obtained which have immunogenic activities similar to the viable attenuated H37Ra cells of Mycobacterium tuberculosis from which they were obtained. This comparison was based on the amount of ribonucleic acid (RNA) present. These preparations consisted of approximately 63% RNA and 37% protein; no deoxyribonucleic acid or polysaccharide was detected by chemical tests. A high correlation was found between the immunogenic activity of a preparation and the per cent increase in hyperchromicity at 260 nm of a ribonuclease-hydrolyzed portion. Final concentrations of sodium dodecyl sulfate higher than 0.25% when used for the preparation of the ribosomal fractions and RNA resulted in significantly lower immune responses and greater variation between experiments. This was not related to the amount of protein present. The stability of the ribosomal and RNA preparations was tested under a variety of conditions. The need for a good protective adjuvant again was shown since mouse serum readily hydrolyzed the RNA. Equal immunity was obtained after immunization by the intraperitoneal and subcutaneous routes; however, no immune response was obtained when the intravenous route was used. Preliminary results with RNA prepared with phenol showed that it was more easily degraded during preparation. This resulted in a lower immune response than was obtained with the RNA prepared with ethyl alcohol.
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PMID:Factors affecting immunogenic activity of mycobacterial ribosomal and ribonucleic acid preparations. 497 47

Bone infection or osteomyelitis is characterized by uncontrolled inflammation and destructive bone loss although little is known about immunopathogenesis of infection. We investigated control of chemokine secretion from osteoblasts infected with either Mycobacterium tuberculosis, which normally elicits a granulomatous host response, or Staphylococcus aureus, which drives a host response dominated by neutrophil influx. We show that M. tuberculosis infection of cultured and primary osteoblasts induces extensive secretion of the chemokines interleukin (IL)-8, inducible protein (IP) 10, RANTES, and monocyte chemoattractant protein (MCP) 1 within 72 h (1630 +/- 280 pg/ml per 4 x 10(5) cells, 74,130 +/- 8480 pg/ml per 4 x 10(5) cells, 18,330 +/- 3040 pg/ml per 4 x 10(5) cells, and 138,670 +/- 13,340 pg/ml per 4 x 10(5) cells, respectively, for MG-63 osteoblasts). S. aureus infection also results in secretion of these chemokines but secretion is delayed and of lesser magnitude (210 +/- 10 pg/ml per 4 x 10(5) cells, 11,570 +/- 1240 pg/ml per 4 x 10(5) cells, 930 +/- 34 pg/ml per 4 x 10(5) cells, and 13,770 +/- 720 pg/ml per 4 x 10(5) cells for IL-8, IP-10, RANTES, and MCP-1, respectively). The minimal up-regulation of secretion of the neutrophil attractant IL-8 in staphylococcal infection is both striking and unexpected. In both infections, chemokine secretion was dependent on the presence of live organisms. Differences in kinetics and magnitude of chemokine secretion are associated with distinct patterns of mRNA expression, as assessed by ribonuclease protection assay (RPA) and reverse-transcription polymerase chain reaction (RT-PCR). In addition, nuclear localization of the transcription factor activator protein (AP) 1 in M. tuberculosis-infected osteoblasts also is distinct as compared with S. aureus-infected cells. In summary, this study shows that osteoblasts have an important pathogen-specific role in control of chemokine gene expression and secretion during the human immune response to osteomyelitis.
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PMID:Differential regulation of chemokine secretion in tuberculous and staphylococcal osteomyelitis. 1221 39

In the present study, we examined profiles of the interaction of Mycobacterium leprae and Mycobacterium avium complex (MAC) with murine peritoneal macrophages (M phi s) in terms of up-regulation of M phi expression of proinflammatory and immunosuppressing cytolines (CKs) after infection. First, the reverse transcription polymerase chain reaction (RT-PCR) assay revealed that both MAC and M. leprae infections up-regulated M phi mRNA expression IL-12, TNF-alpha, IL-10, and transformating growth factor-beta (TGF-beta), except that M. leprae-infected M phi s showed no increase in the IL-12 mRNA expression. Second, the RT-PCR assay also showed some differences between M. leprae- and MAC-infected M phi s with respect to the modes of IL-10 and inducible nitric oxide synthase (iNOS) mRNA expression. That is MAC, but not M. leprae, infection caused a prolonged increase in the expression of IL-10 and iNOS mRNAs. Third, a ribonuclease protection assay revealed that M phi s co-infected with MAC and M. leprae showed the Il-12, TNF-alpha and IL-10 mRNA expression in an intermediate mode of those of M phi s infected with either M. leprae or MAC alone. This implies that the CK expression of M. leprae-infected M phi s may be modified by co-infection with MAC. These findings may suggest differential interactions of M. leprae and MAC organisms with murine peritoneal M phi s in terms of the activation of signal transduction pathways for expression of some kinds of immunoregulatory cytokines and immunoprotective enzymes.
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PMID:Profiles of the mRNA expression by macrophages infected with Mycobacterium leprae and Mycobacterium avium complex. 1276 26

Youmans, Anne S. (Northwestern University Medical School, Chicago, Ill.), and Guy P. Youmans. Nature of the labile immunogenic substance in the particulate fraction isolated from Mycobacterium tuberculosis. J. Bacteriol. 88:1030-1037. 1964.-Deoxyribonuclease had no effect on the immunogenic activity of the labile particulate fraction isolated from ruptured viable cells of the H37Ra strain of Mycobacterium tuberculosis, but decreased the ropiness of the ruptured cellular mass. Ribonuclease, in a high concentration, decreased the immunogenic activity slightly. Addition of yeast ribonucleic acid to particulate fraction incubated at 37 C prevented the decrease in immunogenic activity which normally occurs at this temperature, suggesting that endogenous ribonuclease may be involved in the reduction of activity. Differential centrifugation by the use of Brodie's (1962) method showed that the particles which sedimented at 56,550 x g were immunogenically active. Experiments were done to determine whether the integrity of the structure of the particle was necessary for immunogenic activity. It was found that sonic oscillation, freezing and thawing several times, the addition of surface-active agents (sodium lauryl sulfate or deoxycholate), and preparation of the particulate fraction in hypotonic solutions either decreased or destroyed immunogenic activity. This strengthens the evidence that a structural unit is necessary for activity. In addition, both a waxy sediment and the smallest particles which sedimented only at 144,000 x g were highly immunogenic if incorporated into Freund's incomplete adjuvant. In the absence of adjuvant, neither produced any immunity.
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PMID:NATURE OF THE LABILE IMMUNOGENIC SUBSTANCE IN THE PARTICULATE FRACTION ISOLATED FROM MYCOBACTERIUM TUBERCULOSIS. 1421 15


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