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)

DNA of hepatitis B virus (HBV) of hepatitis B surface antigen (HBsAg) subtype adw2 made fully double stranded by the virion DNA polymerase and radiolabeled either by the virion DNA polymerase reaction or by nick-translation with 32P-labeled deoxynucleoside triphosphates was used to establish a map of restriction endonuclease cleavage sites by the method double and triple enzyme digestion and to determine the relative positions of several unique physical features of this DNA. The five restriction sites for enzyme HincII, the two sites each for BamHI, Ava I, and Bgl II, and the single sites for EcoRI, Pst I, Hpa I, and Taq I were positioned relative to each other. Within this map, the single-stranded region in HBV DNA has been localized and the locations of nicks in each strand (a and b) have been determined with respect to restriction sites on the circular map. Comparison of restriction endonuclease cleavage patterns of DNAs of HBV of HBsAg subtypes adw2, ayw3, and adrq+ revealed consistent differences among subtypes and occasional differences within subtypes.
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PMID:Restriction endonuclease cleavage map and location of unique features of the DNA of hepatitis B virus, subtype adw2. 29 95

DNA extracted from hepatitis B virus Dane particles has been cloned in bacteria using a plasmid vector. A full-length clone has been examined by restriction endonuclease analysis, and the nucleotide sequence of an 892-base pair fragment from cloned hepatitis B viral DNA encoding the surface antigen gene is reported. The amino acid sequence deduced from the DNA indicates that the surface antigens is a protein consisting of 226 amino acids and with a molecular weight of 25,398. The portion of the gene coding for this protein apparently contains no intervening sequences.
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PMID:Nucleotide sequence of the gene coding for the major protein of hepatitis B virus surface antigen. 47 Oct 53

The sensitivity and specificity of the polymerase chain reaction (PCR) in the detection of mycobacteria in paraffin-embedded tissues and in crude lysates of mycobacterial cultures were assessed. Sections of formalin-fixed, paraffin-embedded tissues were deparaffinized and then subjected to a simple proteinase K and boiling lysis procedure. These preparations were used directly for PCR amplification of the 383 bp segment of the gene encoding the 65 kDa mycobacterial surface antigen. Crude lysates of mycobacteria were used as positive controls. The specificity of the PCR products was confirmed by Southern blot using a region-specific digoxigenin-labeled oligonucleotide probe and chemiluminescent detection. The 383 bp diagnostic fragment was visualized in 11 of 12 acid-fast bacilli (AFB) stain/culture-proven-positive blocks. Crude lysates of mycobacteria were detected to a sensitivity of approximately 80 organisms. Amplified fragments from paraffin-embedded tissues and mycobacterial cultures of M. tuberculosis, M. avium-intracellulare, and saprophytic mycobacteria were distinguished by digestion with Nar 1 restriction endonuclease. These results suggest that PCR amplification followed by restriction enzyme digestion of the PCR product is a rapid, specific, and highly sensitive technique for the detection and speciation of mycobacteria in paraffin-embedded tissues.
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PMID:Rapid detection and species identification of mycobacteria in paraffin-embedded tissues by polymerase chain reaction. 134 65

Hepatitis B virus surface antigen (HBsAg) mRNA has been enriched from a hepatoma cell line (PLC/PRF/5) by specific polysome immunoprecipitation and used for cDNA cloning. A HBsAg cDNA clone was identified by in situ hybridization with a cloned viral probe. It was characterized by restriction endonuclease mapping and DNA sequence analysis. Molecular hybridization of PLC/PRF/5 cellular DNA and RNA to [32P]-labeled HBsAg cDNA revealed the integration of at least six copies of the hepatitis B virus (HBV) DNA into the host genome and expression of three DNA species containing HBsAg-specific sequences. The possible role of HBV in the oncogenesis of primary hepatocellular carcinoma is discussed.
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PMID:Molecular cloning and characterization of the cDNA coding for hepatitis B virus surface antigen. 298 65

The HBV DNA isolated from Dane particles of 9 patients' plasma was cloned into the EcoRI or BamHI site of the pUC8 plasmids. Two plasmids with full length HBV DNA and four plasmids containing the HBV surface antigen gene were obtained. Based on our cloned HBV DNA and a comparison with 7 complete sequences and 5 restriction endonuclease patterns of HBV DNA published by others, we can recognize common restriction sites shared by different subtypes (adw, adr, ayw, and adyw): (1) a HincII site in the S gene, (2) a BamHI site in the X region, and (3) two BglII sites in the C gene. In addition adw has specific sites for HincII, BamHI, and PstI in the pre-S region. A unique XhoI site is present in the pre-S region in all subtypes except for adw.
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PMID:Characterization of restriction endonuclease maps of hepatitis B viral DNAs. 299 Apr 68

The entire genome of hepatitis B virus (subtype adr) has been cloned into pBR322. The clones could be classified into at least seven groups by their restriction endonuclease cleavage maps. The nucleotide sequences of the hepatitis B surface antigen (HBsAg)-coding regions for five clones were determined and compared with published sequences of the HBsAg gene including those of adw, ayw, adyw and adr. The 13 available versions of the amino acid sequence of the polypeptide, predicted from the nucleotide sequences, were analysed in terms of the established specificities of the HBsAg, including the four subtypes. The analysis indicated that a relatively hydrophilic region of the HBsAg protein, spanning amino acid residues 110 to 160, specifies the major (w) and (r) subtype system. The (w/r) subtype appears to depend on changes in one or more variable amino acids at positions 47, 110, 113, 126 and 160 of the HBsAg polypeptide.
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PMID:Structural analysis of the gene coding for hepatitis B virus surface antigen and its product. 396 37

Little is known about the replicative forms of hepatitis B virus (HBV) in the liver in chronic liver disease. We therefore analyzed HBV DNA and the changes in DNA signals after endonuclease digestion in liver tissues taken from 64 patients with hepatitis B surface antigen-positive chronic liver disease. The "active" replication pattern, which included various replicative intermediates, was seen in 36 of 38 (95%) hepatitis B e antigen-seropositive patients. This pattern was also found in 5 of 26 (19%) hepatitis B e antigen-seronegative patients who showed the highest mean serum alanine aminotransferase level (403 +/- 184 mU/ml). Most of them had advanced liver disease. Episomal viral DNA of an "inactive" type having only the supercoiled form was found in 3 patients; they showed the lowest mean serum alanine aminotransferase level (27 +/- 7 mU/ml) and only mild liver disease. As with duck HBV infection, episomal replicative forms of human HBV could be resolved by Southern blot analysis and seem to have clinical implications in human HBV infection.
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PMID:Active and inactive replication of hepatitis B virus deoxyribonucleic acid in chronic liver disease. 401 3

The excretory-secretory (E-S) products and surface antigens of 19 isolates of Giardia were compared by reactivity of E-S products with antisera to homologous and heterologous organisms and by acrylamide gel electrophoresis of surface-labeled Giardia. Isolates could be divided into three broad groups on the basis of the previously reported DNA studies and the present studies. Group 1 consisted of five isolates with similar or highly cross-reactive E-S. These showed identical DNA banding patterns after endonuclease restriction analysis; four of five had identical surface antigens, and the remaining isolate showed a similar but different major surface antigen. Group 2 consisted of 11 isolates with moderate reactivity amongst themselves. DNA patterns showed some bands in common with group 1 organisms and themselves, but the surface-antigen molecular weight patterns were different. Group 3 consisted of three isolates with reactivity only amongst themselves. There were no DNA bands in common with group 1, and the molecular weights of the surface antigens were diverse. Surface-antigen differences are common among isolates of Giardia lamblia. These differences correlated to some degree with the DNA banding patterns observed after endonuclease restriction analysis and may result in altered virulence and host response.
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PMID:Differences in excretory-secretory products and surface antigens among 19 isolates of Giardia. 406 31

Hepatitis B virus (HBV) DNA was found to be integrated into seven sites in the DNA of the PLC/PRF/5 hepatoma cell line as determined by digestion with the restriction endonuclease HindIII which does not cut through the viral genome. The integration pattern was stable in the cell line, in tumours induced in athymic mice by this line and in cell lines derived from such tumours. Syntheses of hepatitis B surface antigen and alphafoetoprotein were maintained in the induced tumours and derived cell lines. A defective HBV DNA molecule (approx. 2.8 kilobase pairs) appears to be integrated in a head-to-tail tandem arrangement and it is proposed that such defective molecules may be involved in the process of neoplastic transformation by HBV.
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PMID:Defective hepatitis B virus DNA molecules detected in a stable integration pattern in a hepatoma cell line, and in induced tumours and derived cell lines. 619 51

PLC/PRF/5, a tissue culture cell line isolated from a human hepatocellular carcinoma and producing hepatitis B surface antigen, was studied for the presence of hepatitis B virus (HBV)-specific DNA and RNA. PLC/PRF/5 cell DNA accelerated the rate of reassociation of HBV [32P]DNA, and quantitative experiments indicated that the cells contained approximately four copies of viral DNA per haploid, mammalian cell DNA equivalent. PLC/PRF/5 DNA accelerated the rate of reassociation of all individual restriction endonucleases HincII and HaeIII fragments of HBV [32P]DNA, indicating that DNA from all regions of the viral genome is present in the cells. This suggests that these cells contain at least most, and possibly all, of the viral genome. Digestion of PLC/PRF/5 cell DNA with restriction endonuclease HindIII (an enzyme found not to cleave the DNA of any HBV isolate so far examined) yielded only three fragments, all larger than virion DNA, which contained HBV DNA base sequences, suggesting that HBV DNA is integrated in high-molecular-weight DNA at three different sites in these cells and that there is no viral DNA in an episomal form. PLC/PRF/5 cell [32P]RNA was found to hybridize with all restriction fragments of HBV DNA adequately tested, indicating that at least most, and possibly all, of the viral DNA in these cells is transcribed.
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PMID:State of hepatitis B viral DNA in a human hepatoma cell line. 625 Dec 50


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