Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q17RS7 (Gen)
 130,125 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It has been shown that particles of Vi bacteriophage III catalyse deacetylation of O-acetyl pectic (polygalacturonic) acid, a structural analogue of Vi polysaccharide (Vi antigen). Using this substrate, and determining the acetic acid liberated by gas-liquid chromatogrphy, a method for the estimation of Vi phage deacetylase activity has been developed. Purified particles of Vi phage III were exposed to a variety of mildly dissociative reagents and conditions, and then tested for plaque-forming and for deacetylase activity. They have also been inspected under the electron microscope. Osmotic shock, and incubation in the presence of ethylenediamine tetraacetic acid (greater than or equil 0-01 M), or of L-arginine (0-25 M), were found to cause disintegration of the virions into empty head capsids, deoxyribonucleic acid, and base plates still carrying the spikes. The mixtures of viral fragments exhibited an increased deacetylase activity. Using zonal sedimentation and ion exchange chromatography, the phage fragments obtained by treatment with ethylenediaminetetraacetic acid have been fractionated and the base plates isolated. Amongst the viral components, these structures showed the highest specific deacetylase activity. They had the shape of six-pointed stars (about 9-5 nm inner, and 14-5 nm outer diam.) with a central hole or plug (approximately 3 nm), carrying six spikes, roughly cylindrical organelles of approx. 11 X 4 nm, one at each of the points. Of the polypeptides of six sizes (P.1, about 153,000 daltons; P.2, 91,000; P.3, 71,000; P.4 56,500; P.6, 22,000), detected in whole Vi phage III virions by sodium dodecyl sulphate-polyacrylamide gel electrophoresis, only two, P.2 and P.3 were found in the base plates.
J Gen Virol 1975 Dec
PMID:Disruption of Vi bacteriophage III and localization of its deacetylase activity. 0 68

Human papovavirus, RFV, isolated from urine of a renal transplant patient was compared with two strains of SV40 and with the prototype human papovavirus, BKV. Neutralization tests showed that RFV and BKV are indistinguishable, while large-plaque (LP) and small-plaque(SP) isolates of SV40 gave a low but significant level of cross-reaction with rabbit or human antisera against RFV. DNA reassociation saturation tests using 125I-labelled RFV DNA show that BKV has 88% homology, and SP-SV40 has 29% homology to RFV. We conclude that RFV and BKV are nearly, if not totally, identical and are not SV40 variants.
J Gen Virol 1977 Apr
PMID:Characterization of human papovavirus RFV: comparison with SV40 and BKV. 6 83

Kethoxal bis (thiosemicarbazone) (KTS) inhibited replication of, and plaque formation by, vesicular stomatitis virus (VSV) in chick embryo cells. No other thiosemicarbazones tested were effective. Virus-specific m-RNA and protein synthesis were inhibited by KTS. However, virion RNA-dependent RNA synthesis was not inhibited by the drug. Treatment of VSV virions directly with KTS produced enhancement, rather than inactivation, of plaque formation. KTS inhibited cellular DNA and RNA synthesis by 67 and 25% respectively. Since cellular DNA and RNA synthesis are not required for VSV replication, the inhibition of these processes is probably unrelated to the antivirial activity of KTS. Cellular protein synthesis was inhibited 24% by KTS. Unexpectedly, synthesis of four proteins was induced in KTS-treated uninfected cells.
J Gen Virol 1977 Oct
PMID:Inhibition of vesicular stomatitis virus by kethoxal bis (thiosemicarbazone). 7 31

Four of eight mycobacteriophages did not form plaques after they were exposed to chloroform. Phages sensitive to chloroform did not produce plaques when plated on media containing 1000 microgram/ml of streptomycin sulphate. The same concentration of dihydrostreptomycin sulphate did not interfere with plaque formation. Mutants of Mycobacterium smegmatis resistant to each of the eight phages were isolated. Sensitivity or resistance to chloroform and streptomycin sulphate and phage resistant bacterial mutants may provide a basis for classifying the mycobacteriophages.
J Gen Virol 1978 Jun
PMID:Resistance relationships in Mycobacterium smegmatis ATCC 607 to phages sensitive or resistant to both chloroform and streptomycin sulphate. 7 94

Direct plaque formation with representative strains of hog cholera virus (HCV) has been obtained using several pig kidney cell lines under agar overlay. HCV-infected cells appear as hazy plaques when viewed against an indirect light source, and as white plaques after neutral red staining. HCV assay by direct plaque procedure is rapid and convenient and gives infectivity titres identical to the fluorescent focus assay technique.
J Gen Virol 1978 Jul
PMID:A direct plaque assay for hog cholera virus. 8 Apr 44

Twelve influenza A viruses, antigenically related to the Ho, H1 and Hsw1 subtypes, were isolated from cloacal samples of feral ducks in Canada. Antigenic comparisons showed that these viruses were most closely related to the recent HSW1N1 isolates from man and pigs, whereas in vivo pathogenicity tests revealed differences between the Hsw1N1 viruses from the ducks and those from humans and pigs. Antigenic characterization of 94 additional influenza A viruses from the ducks showed four haemagglutinin subtypes (Hav1, Hav4, Hav5 and Hav7), an unclassified haemagglutinin, and six neuraminidase subtypes (N1, N2, Neq2, Nav1, Nav2 and Nav5) in various combinations, some of which are novel and have not previously been reported. Three of these duck influenza viruses possessed a haemagglutinin antigenically related to that of classical fowl plaque virus. A much higher percentage of virus isolations were from juvenile ducks (18.5%) than from adults (5%). All of the ducks, from which viruses were isolated, appeared healthy at the time of sampling. Serological studies on a limited number of humans and domestic birds living in close proximity to the Canadian ducks revealed no evidence of interspecies transmission. Our findings suggest that these birds serve as a substantial reservoir of antigenically diverse influenza viruses, including isolates antigenically related to the current human and animal influenza viruses. This reservoir in nature may be perpetuated by a cycle involving annual infection of juvenile birds followed by transmission to the remaining susceptible birds until the next congregation during the breeding season.
J Gen Virol 1978 Oct
PMID:Novel influenza A viruses isolated from Canadian feral ducks: including strains antigenically related to swine influenza (Hsw1N1) viruses. 8 Dec 67

Antigenic differences were demonstrated between the large and small plaque variants of both types O1 and Asia-1 foot-and-mouth disease viruses. Treatment of the large and small plaque variants of the viruses with trypsin essentially abolished the observed antigenic differences. Thus, these plaque variants have antigenically different trypsin-sensitive determinants that may influence their immunogenicity and infection capabilities.
J Gen Virol 1978 Nov
PMID:Effect of trypsin treatment on the antigenic characteristics of plaque variants of type-O 1 and type Asia-1 foot-and-mouth disease viruses. 8 10

Large and small plaque variants of A12 foot-and-mouth disease virus were shown to have specific antigenic determinants. Large plaque virus antigenic specificity was destroyed by trypsin treatment, but the small plaque antigen was resistant despite cleavage of the trypsin-sensitive polypeptide. The cleavage of polypeptide VP3 by trypsin resulted in the formation of a new antigen not present on untreated virus. The effects of chymotrypsin and trypsin on the polypeptides of the plaque variants have been examined and related to changes in antigenicity, infectivity, and exposure of the polypeptides at the surface of the capsid. The results are discussed in relation to the orientation of the trypsin-sensitive polypeptide in the virus capsid.
J Gen Virol 1978 Dec
PMID:Effect of trypsin and chymotrypsin on the polypeptides of large and small plaque variants of foot-and-mouth disease virus: relationship to specific antigenicity and infectivity. 8 54

Antigenic relationships among seven California group strains were studied by a plaque-reduction neutralization test (PRNT). Cross-reactions occurred in most cases but three subgroups were noted: (1) the major serogroup contained the viruses of California encephalitis, LaCrosse, Snowshoe Hare and Trahyna (including the Lumbo strain) whereas (2) Jamestown Canyon and (3) Trivittatus viruses were distinct. There was no significant difference between the PRNT results in mammalian (PS) cells incubated at 37 degrees C and amphibian (XTC-2) cells incubated at 28 degrees C. Trivittatus virus failed to produce plaques in XTC-2 cells.
J Gen Virol 1979 Feb
PMID:Cross-neutralization study of seven California group (Bunyaviridae) strains in homoiothermous (PS) and poikilothermous (XTC-2) vertebrate cells. 8 57

Various strains of influenza C virus grew productively in an established line of monkey kidney cells (LLCMK2) without prior adaptation. When trypsin was added to the medium, higher virus yields were obtained than in other cell cultures. All influenza C virus strains tested formed well defined plaques under the agar overlay medium containing trypsin. Infectivity determined by plaque assay in LLCMK2 cells was higher than that determined by amniotic inoculation of fertile hens' eggs.
J Gen Virol 1979 Apr
PMID:Established cell line sensitive to influenza C virus. 11 96


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