Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Restriction endonucleases are bacterial enzymes that cleave DNA at specific sites. The resulting DNA fragments may be separated electrophoretically in gel to form specific restriction patterns. In the present study, the restriction endonuclease method was successfully adapted to the analysis of the chromosomal DNA of Neisseria meningitidis. The endonucleases HindIII and EcoRI provided optimal restriction patterns of ca. 50 well-separated lines. The pattern of each bacterial isolate was characteristic, stable, and reproducible. Despite some general similarity, the restriction patterns of the closely related B15 meningococci were surprisingly heterogeneous.
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PMID:Applications of restriction endonuclease fingerprinting of chromosomal DNA of Neisseria meningitidis. 608 70

The restriction endonuclease fingerprinting technique was applied to meningococcal DNA in an attempt to identify individual strains of Neisseria meningitidis B15 (serogroup B, serotype 15), which causes approximately 90% of cases of meningococcal disease in northern Norway. Thirty representative strains (10 each from asymptomatic pharyngeal carriers, patients with septicemia, and patients with meningitis) were investigated with the restriction endonucleases Hind III and Eco RI. The 10 carrier strains showed a remarkable heterogeneity of fingerprints that rendered each strain easily distinguishable from the others. The 10 strains from the blood and the 10 from the cerebrospinal fluid showed similar but not identical restriction patterns. The results obtained with the two endonucleases were in perfect agreement. Our data suggest that a large number of different B15 clones are present in the population of northern Norway, but that only one single clone causes invasive meningococcal disease.
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PMID:Differentiation of B15 strains of Neisseria meningitidis by DNA restriction endonuclease fingerprinting. 609 87

We have successfully developed a restriction endonuclease fingerprinting (REF) technique for the study of meningococcal chromosomal DNA. A review of our application of this method in studies of meningococcal epidemiology and pathogenicity is given. By REF we could show that fingerprints of apparently identical B15 carrier strains were remarkably heterogeneous, whereas invasive B15 isolates possessed very similar fingerprints. We could also demonstrate REF heterogeneity among B15 isolates collected from cases with meningococcal disease and their close contacts during an outbreak of meningococcal disease in a military camp in North Norway. The REF technique has also proved valuable for our studies on meningococcal piliation and adherence. At present, we are studying 67 different meningococcal isolates collected from all parts of Norway during the MenOPP project.
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PMID:Restriction endonuclease fingerprinting of meningococcal DNA. 614 94

Cellular DNA from HLA-typed individuals was digested with the restriction endonucleases HindIII, EcoRV, and EcoRI. The separated restriction endonuclease fragments were hybridized with a HLA class I cDNA probe by using the Southern transfer technique. Digestion of cellular DNA with HindIII generated 22 restriction endonuclease fragments, 11 of which showed polymorphism for presence or absence in a population sample. With EcoRV, 13 fragments were identified; 6 showed polymorphism. EcoRI generated 11 fragments, of which 1 was polymorphic. Of these 18 polymorphic fragments generated by the three restriction endonucleases, each of 5 was found to be positively associated with one allele of the HLA-A or -B allelic series (HLA-Aw24, -B8, -B15, -Bw35, and -B40). One fragment was positively associated with two HLA-A series alleles (HLA-A1 and -A11). Another fragment was positively associated with five HLA-B series alleles (HLA-B5, -B7, -B14, -Bw16, and -Bw35) and one fragment was positively associated with alleles at two loci (HLA-B14 and -Cw5). The serologically defined allele HLA-Aw24 was associated with two polymorphic fragments, one association showing a positive correlation and the other a negative correlation. Each informative family studied thus far has shown segregation of the restriction fragment with the associated serologically defined allele. The fragments associated with serologically defined alleles occurred in the population sample studied at low or moderate frequencies. The remaining polymorphic fragments occur at high frequency, suggesting that class I genes not serologically detected show less polymorphism than serologically defined class I genes.
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PMID:Analysis of HLA class I genes with restriction endonuclease fragments: implications for polymorphism of the human major histocompatibility complex. 631 51