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)

Thirteen different serogroup strains of Yersinia pseudotuberculosis and two strains of Yersinia enterocolitica O:3 were examined for the presence of plasmids and plasmid-mediated properties, calcium growth dependency, and autoagglutination. Two Y. enterocolitica strains and eight serogroup (IA, IIA, IIC, III, IVA, VB, VI, and VIII) strains, except for five serogroups (IB, IIB, IVB, VA, and VII), of Y. pseudotuberculosis harbored plasmids ranging in molecular size from 27 to 115 kilobases. Filter hybridization of restriction endonuclease-digested plasmid DNA from different serogroup strains indicated that all plasmid DNAs conferring calcium growth dependency and autoagglutination shared a high degree of DNA sequence homology, regardless of the different serogroups of Y. pseudotuberculosis and Y. enterocolitica.
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PMID:Plasmid DNA relatedness among different serogroups of Yersinia pseudotuberculosis. 398 10

We examined a group of 23 recent clinical isolates of Yersinia enterocolitica recovered from symptomatic patients residing in the New York, N.Y. area. These isolates were tested for the presence of plasmids, exoenzyme activity, mouse lethality, and phenotypic properties postulated to correlate with virulence. Of the 23 isolates, 17 harbored a 60- to 65-kilobase (kb) plasmid. Six isolates were lethal for white mice, showed the phenotypic markers of autoagglutination and calcium dependence for growth at 37 degrees C, and contained a 60- to 65-kb plasmid. Restriction endonuclease analysis with several different enzymes revealed the presence of three distinct plasmid profiles in these isolates. Isolates with a single plasmid of 60 to 70 kb, typical for this species, were detected, but these were of three distinct types as judged from restriction enzyme digestion. One strain was unusual among clinical isolates of Y. enterocolitica in that it contained at least four distinct plasmids. In addition, this nontypable strain showed exoenzymatic activity similar to that of serogroup O8 isolates, was not lethal to mice, and did not require calcium for growth at 37 degrees C.
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PMID:Assessment of plasmid profile, exoenzyme activity, and virulence in recent human isolates of Yersinia enterocolitica. 404 2

The virulence plasmids pYV019, pYV8081, and pIB1 from Yersinia pestis, Yersinia enterocolitica, and Yersinia pseudotuberculosis, respectively, were characterized by restriction endonuclease analysis. The three plasmids exhibited a region of common DNA previously shown to encode determinants which confer Ca2+ dependence. The plasmids from Y. pestis and Y. pseudotuberculosis were similar throughout their genomes. In contrast, a region of the plasmid from Y. enterocolitica which contained an origin of replication differed from the other two plasmids as determined by DNA homology and replication properties. Plasmid-associated outer membrane proteins from all three species of Yersinia were characterized by polyacrylamide gel electrophoresis. There were no differences in the outer membrane protein profiles between plasmid-containing and homogenic strains lacking the plasmid after growth at 28 degrees C. After growth at 37 degrees C, both Y. enterocolitica and Y. pseudotuberculosis showed at least four major plasmid-associated outer membrane proteins. Y. pestis did not show any discernible changes after growth at 37 degrees C. It was shown by using E. coli minicell analysis that the plasmid DNA from all three species of Yersinia contained the coding capacity for production of the novel outer membrane proteins.
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PMID:Characterization of common virulence plasmids in Yersinia species and their role in the expression of outer membrane proteins. 631 62

A portion of a 44-megadalton plasmid found in Yersinia enterocolitica 8081 was used as a genetic probe to differentiate virulent and nonvirulent strains of the species. A DNA colony hybridization technique was employed. Three BamHI restriction endonuclease fragments labeled with 32P by nick translation were hybridized to lysed colonies of pure cultures, mixtures of virulent and nonvirulent cells, and portions of a food sample artificially contaminated with virulent Y. enterocolitica. The results of the colony hybridization test for virulence were the same as those obtained by the autoagglutination and suckling mouse tests. DNA colony hybridization detects pathogenic Y. enterocolitica in foods without the need for enrichment or pure cultures.
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PMID:Detection and enumeration of virulent Yersinia enterocolitica in food by DNA colony hybridization. 663 17

The possession of a 42- to 48-megadalton plasmid alone does not appear to be predictive of virulence in Yersinia species. Twelve of 100 Yersinia enterocolitica strains contained a 42 to 48-megadalton plasmid, and 4 of 30 Y. enterocolitica-like strains contained a 42- to 48-megadalton plasmid. Seven strains of Y. enterocolitica contained the 42- to 48-megadalton plasmid plus an 82-megadalton plasmid, and these were the only study strains lethal for mice. Based on restriction endonuclease digestion, the 42- to 48-megadalton plasmid DNA from these seven strains were similar and were not similar to the 42- to 48-megadalton plasmids present in the other nine strains. The ability to invade guinea pig eye tissues, calcium dependency, autoagglutination, and colonial morphology at 37 degrees C were also associated with plasmid DNA, but the relationships were either variable or not reciprocal. Neither tissue culture invasiveness nor heat-stable toxin production was associated with plasmid DNA. It was concluded that biochemical speciation and a total plasmid profile in combination with enzyme digests are predictive of virulence in Y. enterocolitica as it is measured by mouse lethality.
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PMID:Diagnostic value of plasmid analyses and assays for virulence in Yersinia enterocolitica. 674 1

One-hundred fifteen strain of Yersinia enterocolitica were examined for plasmids and plasmid-mediated pathogenic properties. Human strains of serotypes O:3 and O:9 harbored plasmids of 46 and 44 megadaltons, respectively, with 90% homology of DNA sequences. The plasmid-mediated properties were calcium dependence, survival in human serum, conjunctivitis provocation in guinea pigs, and O agglutinogens. One strains of serotype O:8 harbored a 42-megadalton plasmid with 75% sequence homology with plasmids of serotypes O:3 and O:9. An additional plasmid-mediated property was lethality for white mice. Filter hybridization of restriction endonuclease-digested plasmid DNA indicated that a 5.6-megadalton fragment of the plasmid of serotype O:8 had virtually no sequence homology with plasmid DNA of serotypes O:3 and O:9 and therefore may be associated with the lethal factor for mice.
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PMID:Plasmids of human strains of Yersinia enterocolitica: molecular relatedness and possible importance for pathogenesis. 682 45

The genomes of three main biovars of Yersinia pestis were subjected to restriction fragment length polymorphism analysis using I-CeuI endonuclease. I-CeuI which is encoded by a mobile intron in Chlamydomonas engamenans recognizes a 25-bp site in the ribosomal RNA rrl gene and cuts DNA of most representatives of Enterobacteriaceae into seven fragments corresponding to the presence of seven rrn-operons. Glycerol-positive Y. pestis strains (biovars antiqua and mediaevalis) contain seven ribosomal operons which can be recognized by I-CeuI endonuclease. However, glycerol-negative strains of Y. pestis biovar orientalis expose only six restriction sites for I-CeuI. The restriction fragment length polymorphism patterns obtained with I-CeuI make it possible to distinguish between three biovars of Y. pestis. Use of another rare cutting restriction enzyme, Bln/I, permits differentiation between pigment-adsorbing and avirulent non-pigment-adsorbing Y. pestis. Still, due to homologous recombination between the two copies of IS 100 insertion sequence bracketing the pgm-locus, the mechanism of deletions in the pgm-locus seems to be confined only to strains of biovars antiqua and mediaevalis, and can be different in Y. pestis strains of biovar orientalis. The I-CeuI restriction patterns of two Yersinia strains isolated within a ten-year period in the port of St. Petersburg and originally identified as Y. pseudotuberculosis 01 turned out to be related to typical representatives of Y. pestis biovar antiqua. These strains could be exported from the same source or circulate among Rattus norvegicus population of the port as non-pigment-adsorbing avirulent immunogenic clone.
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PMID:The established Yersinia pestis biovars are characterized by typical patterns of I-CeuI restriction fragment length polymorphism. 747 35

Yersinia enterocolitica gastroenteritis was first recognized in the early 1960s and has since been reported with increasing frequency. To determine if strains of Y. enterocolitica, within a restricted region isolated over 8 years (1985-1993), originated from a single or multiple clones, pulsed-field gel electrophoresis (PFGE) of large chromosomal DNA restriction fragments generated by XbaI or NotI was used. A total of 27 isolates of Y. enterocolitica were analyzed, 24 from Austria (Vienna and Graz) consisting of serogroups 0:3 (17 isolates), 0:9 (6 isolates), 0:5 (1 isolate); 2 from Germany of serogroups 0:3 and 0:9 (1 isolate each); 1 from the U.S.A. of serogroup 0:8. Genomic fingerprints of these strains were compared to those of 8 other Yersinia species to ascertain if their restriction endonuclease digestion profiles (REDP) were serogroup and/or species specific. The 27 Y. enterocolitica strains could be divided into 16 genomic varieties according to their restriction patterns with NotI and XbaI. PFGE was highly discriminatory as strains belonging to the same serogroup could be subdivided into different genomic groups. Furthermore, Y. enterocolitica strains isolated from the same region, over an 8 year period, belonged to a few closely related clones. The genomic fingerprints of Yersinia were found to be species and serogroup specific.
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PMID:Clamped homogenous electric fields (CHEF) gel-electrophoresis of DNA restriction fragments for comparing genomic variations among strains of yersinia enterocolitica and Yersinia spp. 772 92

Sixty strains of Yersinia enterocolitica from five serogroups (O:3; O:9; O:8; O:5; and O:5,27) and eight non-Y. enterocolitica strains, recovered from diverse sources (humans, animals, food, and the environment) in Europe, Argentina, and the United States, were examined by the pulsed-field gel electrophoresis (PFGE) technique of contour clamped homogeneous electric field electrophoresis (CHEF) by using NotI and XbaI as restriction enzymes. NotI and XbaI generated 36 and 33 restriction endonuclease digestion profiles (REDP), respectively. By combining the results of both enzymes, 42 unique genomic groups were differentiated. DNA fragments were transferred to nylon membranes and hybridized with digoxigenin-labelled oligonucleotide probes to the ail gene and virulence plasmid to determine hybridization patterns and the potential virulence of the strains. The strains were tested for the presence of the plasmid by PFGE-CHEF and phenotypic characteristics encoded for by the virulence plasmid. Thirty of the 60 Y. enterocolitica strains tested harbored the virulence plasmid. The specificity of the ail and pYV probes was 100% when tested with 68 Yersinia strains and 19 different non-Yersinia strains. Sixteen selected Y. enterocolitica strains were tested for their virulence by lethality in iron- and desferrioxamine-sensitized mice. No correlation between REDP and the virulence of the strains was observed. The observed REDP and the hybridization patterns were very homogeneous within a serogroup and independent of the source of isolation. In addition, PFGE-CHEF was shown to be valuable in identifying and confirming serogroups. Principal component analysis of Dice similarity indices from REDP was an excellent tool for determining genetic relatedness among strains.
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PMID:Molecular characterization of Yersinia enterocolitica by pulsed-field gel electrophoresis and hybridization of DNA fragments to ail and pYV probes. 781 Oct 77

Restriction endonuclease analysis of virulence plasmid DNA was used to study the epidemiology of Yersinia pseudotuberculosis infections. The origin of Y. pseudotuberculosis could be divided into two focus areas: Eastern Asia and Europe. Wild animals were an important reservoir for the Y. pseudotuberculosis seen in infections in humans.
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PMID:Restriction endonuclease analysis of virulence plasmids for molecular epidemiology of Yersinia pseudotuberculosis infections. 791 10


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