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)

Deletions contained within the genomes of unstable and stable variants of vaccinia virus (strain WR) were analyzed. Restriction endonuclease mapping and hybridization to specific 32P-labeled DNA probes indicated that more than 6 X 10(6) daltons of DNA were deleted from the variants. In each case, the deletion occurred on the left side of the genome and started very close to the junction of the inverted terminal repetition and unique sequence. Both variants also contained a new SstI side on the right side of the genome. Hybridization selection and cell-free translation experiments indicated that these variants lost the ability to synthesize at least eight early mRNA's mapping within the deleted region. Although the deleted DNA was not essential for replication of the WR strain of vaccinia virus under laboratory conditions of infection, it presumably has a defined role under other circumstances. This conclusion was based on the conservation within the Elstree strain of vaccinia, the Utrecht strain of rabbitpox, and the Brighton strain of cowpox virus of sequences homologous to the deleted DNA. Moreover, mRNA's that hybridized to the deleted vaccinia virus DNA segment and encoded similar size polypeptides were made in cells infected with rabbitpox and cowpox viruses.
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PMID:Deletion of a 9,000-base-pair segment of the vaccinia virus genome that encodes nonessential polypeptides. 627 95

The white pock variant of cowpox virus shows limited growth in chick embryo fibroblasts maintained in arginine-deprived culture medium. Since these conditions inhibit the growth of parental virus, there is a marked increase in the frequency of the white variant in the virus population recovered after passage in the absence of arginine. The variants generated in this system have been characterized by restriction endonuclease analysis of virus DNA in the total DNA recovered from infected cell cultures. Such analysis shows that the white variants arise as deletion mutants of the parental virus, but there was considerable heterogeneity in the restriction patterns of different isolates examined shortly after their generation. Further passage selected white cowpox virus populations with a stable genome configuration comparable with the DNA of pock-purified white variants.
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PMID:Arginine deprivation and the generation of white variants in cowpox virus-infected cell cultures. 629 24

A previous report described restriction endonuclease analysis of white pock variants of red cowpox virus and their characterization as deletion mutants lacking certain sequences including the repetition from one specific terminus of the wild-type genome. Further analysis has confirmed the terminal deletion but demonstrated that this is compensated at the site of deletion by the presence of an inverted duplication of a variable amount of sequence from the opposite terminus, with the effect of restoring a terminal repetition and the covalent, terminal crosslink. Nine of 11 white pock variants showed a similar deletion of about 21 Mdal mapping contiguously from the right-hand terminus and extending into a 2.4 Mdal restriction fragment. Two white variants showed larger deletions of about 24 and 27 Mdal respectively. These deletions were compensated by a copy of sequences from the opposite terminus which ranged in size from 3 to 27 Mdal. No terminal deletions smaller than 21 Mdal were observed in cowpox white variants or in clones retaining the red phenotype. In contrast with other orthopoxviruses, no deletions involving the left-hand terminus were found. Some independent white isolates had similar sizes of sequence copied from the opposite terminus, but some sibling clones from a single, pock-purified white isolate with the same size of deletion had different sizes of duplicated sequence. Other siblings isolated from an independent, three times pock-purified white clone, itself derived from a single parental red pock, differed from each other in the size of both the deletion and the duplicated sequence. These observations suggest preference for deletion in a particular region, conjunction of the genome termini during DNA replication and a requirement for the preservation of symmetrical termini in orthopoxvirus genome function.
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PMID:The genome structure of cowpox virus white pock variants. 632 86

We report the first isolation of cowpox virus from a domestic cat in Norway, and the first confirmed isolation of cowpox virus from a human case in Norway. These two Norwegian cowpox virus isolates, as well as two Swedish human isolates, were partially characterized and compared with each other and with cowpox virus Brighton and vaccinia virus strain Western Reserve. Restriction enzyme analysis of the genomes revealed differences between all six viruses examined, but suggested that the two Norwegian isolates are closely related, as are the two Swedish isolates. Restriction endonuclease digestion of genomic DNA demonstrated that one of the Swedish isolates and the two Norwegian isolates have larger genomes than vaccinia virus strain Western Reserve, but smaller than cowpox Brighton. All four Scandinavian isolates lacked a 72 base-pair region within the A-type inclusion body protein gene which is present in the prototype cowpox virus Brighton.
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PMID:Characteristics of four cowpox virus isolates from Norway and Sweden. 972 95

Fourteen orthopoxvirus strains isolated from humans, cats, a dog, a cow, and an elephant in Germany were characterized. All were classified as cowpox virus based on haemorrhagic lesions induced on the chorioallantoic membrane of chicken eggs and reactivity of a 160 kDa protein with anti-A-type inclusion protein hyperimmune serum in a Western blot. More detailed comparison of the isolates by restriction endonuclease mapping using HindIII and XhoI demonstrated a close relationship between all isolates and confirmed them as cowpox viruses. However, some minor differences between the isolates were detected which proved to be of epidemiological value. One group consisting of five closely related isolates contained a unique 4.0 kb HindIII fragment. In a Southern blot this fragment failed to hybridize with other cowpox virus isolates including the reference strain.
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PMID:Characterization of orthopoxviruses isolated from man and animals in Germany. 1022 15