Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| antibody response to the rubella virus structural proteins in infants with the congenital rubella syndrome. | forty-five serum samples from 31 newborns and infants with the congenital rubella syndrome (crs) were tested by immunoprecipitation to determine their antibody spectra to each of the structural proteins of rubella virus. most sera (37/45) contained little or no e2 protein-specific antibody, but some (6/45) precipitated a greater amount of the e2 glycoprotein than the e1 glycoprotein. the relative e1/e2 ratio was found to decrease with time when serial serum samples from the same patient were tes ... | 1986 | 3723114 |
| detection of antibodies to individual proteins of rubella virus. | individual rubella virus structural polypeptides were electroeluted from sds-polyacrylamide gels. the eluted polypeptides were used, without further purification, as antigens in elisa assays for the detection of rubella-specific antibodies in patients' sera. this provided a more sensitive detection method than that involving classical serological assays such as hi or vn or that using immunoprecipitation. antisera against individual viral polypeptides were raised in mice. no haemagglutination inh ... | 1986 | 3734013 |
| mutants of the membrane-binding region of semliki forest virus e2 protein. i. cell surface transport and fusogenic activity. | three mutations of the membrane-binding region of the semliki forest virus (sfv) p62 polypeptide (the precursor for virion e3 and e2) have been made by oligonucleotide-directed mutagenesis of a cdna clone encoding the sfv structural proteins. one of the mutations (a2) substitutes a glu for an ala in the middle of the hydrophobic stretch which spans the bilayer. a1 and a3 alter the two basic charged amino acids in the cytoplasmic domain next to the hydrophobic region. the wild-type charge cluster ... | 1986 | 3753980 |
| molecular determinants of alphavirus neurovirulence: nucleotide and deduced protein sequence changes during attenuation of venezuelan equine encephalitis virus. | the nucleotide and deduced amino acid sequences of the structural proteins of the tc-83 vaccine strain of venezuelan equine encephalitis (vee) virus have been determined from a cdna clone containing the 26s mrna coding region. a cdna clone encoding the equivalent region of the virulent parent vee virus [trinidad donkey strain (trd)] has been sequenced previously. comparison of the sequences of the tc-83 and trd cdna clones revealed 13 nucleotide differences. neither the organization of the struc ... | 1986 | 3755750 |
| molecular cloning and sequencing of the region of the rubella virus genome coding for glycoprotein e1. | the sequence of the 1600 3' terminal nucleotides of the rna of rubella virus was determined from cdna synthesized from both virion and intracellular rna using reverse transcriptase and an oligodeoxythymidine primer and cloned into a bacterial plasmid vector. this sequence contained the complete coding sequence for virion envelope protein e1 and a 57 nucleotide nontranslated region between the stop codon for e1 and the poly a tract. the predicted size for e1 was 481 amino acids and within this se ... | 1986 | 3755848 |
| characterization of a protein fatty acylesterase present in microsomal membranes of diverse origin. | a microsomal activity of baby hamster kidney cells which cleaves ester-type bound fatty acids from acyl proteins in vitro has been characterized. this activity is also present in microsomal membranes from pig liver, calf kidney, and human mucous cells. cell free deacylation is described for the semliki forest virus acyl proteins e1 and e2 and the precursor of e2 designated p62. acyl chain cleavage operates with both exogenous and endogenous viral acyl protein substrates. the in vitro cleavage re ... | 1986 | 3771557 |
| role of prostaglandins and non-steroid anti-inflammatory drugs in the pathogenicity of vaccinia virus. | the effect of prostaglandins (pgs) of the a series (a1 and dimethyl pga2), e1, d2, f2 alpha and pgi2 (prostacyclin) and of inhibitors of pg synthesis (aspirin and indomethacin) on the pathogenicity of vaccinia virus was studied in balb/c mice. pgs of the a series, d2 and f2 alpha conferred little or no protection to mice against the lethal effects of vaccinia virus. mice treated with pge1 showed a dramatic increase in mortality after viral infection. however, when mice were treated with pgi2, th ... | 1987 | 3819698 |
| structural and functional homology of parvovirus and papovavirus polypeptides. | we have compared the sequences of the putative polypeptides of the human pathogenic b19 parvovirus with protein sequences in the national bethesda research foundation library, and have discovered a significant homology between a b19 parvovirus non-structural (ns) protein and the t antigens of polyomaviruses and simian virus 40 (sv40) and the putative e1 proteins of papillomaviruses. the region of highest homology with the papovavirus proteins corresponds to the region that is most highly conserv ... | 1987 | 3819702 |
| [identification of monoclonal antibodies against protein e1 of venezuelan equine encephalomyelitis virus blocking the hemagglutinating but not the infective activity of virions]. | cellular clone (mak 14-7), producing antibodies against the virus of venezuela equine encephalomyelitis (vee), strain 230, was isolated using the standard hybridomata technology. monoclonal antibodies neutralized the viral hemagglutinating activity leaving the infectious one intact. monoclonal antibodies from mad 14-7 reacted specifically with viral glycoprotein e1 as registered by the immunoprecipitation technique. the topography of antigenic determinants of viral e1/e2 glycoprotein dimer formi ... | 1985 | 3842754 |
| comparative structural analysis of hla-a3 antigens distinguishable by cytotoxic t lymphocytes: variant e1. | influenza-specific cytotoxic t cells restricted by hla-a3 recognize differences between hla-a3 antigens that are serologically indistinguishable. to examine whether this differential recognition had a structural basis, we have compared the structures of hla-a3 molecules from epstein barr virus-transformed peripheral blood lymphocytes of two individuals, e1 and m17. m17 was representative of the majority of hla-a3-bearing individuals, whereas e1 was a variant distinguished by cytotoxic t cells. p ... | 1985 | 3871112 |
| cross-reactive target antigen in cell-mediated cytolysis of cells infected with a temperature-sensitive mutant of sindbis virus. | cytotoxic t lymphocytes (ctl) against alphavirus-infected l929 cells were generated in mice by two in vivo immunizations of one virus or by in vivo immunization followed by in vitro stimulation of splenocytes with infected peritoneal exudate cells or splenocytes. these ctl caused specific h-2-restricted cytolysis equally well with homologous, heterologous or sindbis virus ts20 mutant-infected cells. thus, specific ctl appear to be cross-reactive components in normal immunity to alphaviruses and ... | 1985 | 3873514 |
| transformation by human adenoviruses. | when, approximately 10 years ago, it was shown that the functions essential for cell transformation were localized in a small region of the adenovirus genome, a dna segment which at that time was thought to be capable of encoding two or three average-sized proteins at most, it seemed reasonable to hope that an understanding of the mechanisms by which adenoviruses transform cells might be quickly achieved. while such optimism might be forgiven, it was quite clearly naive in the extreme. as a cons ... | 1985 | 3886009 |
| markers of venezuelan encephalitis virus which distinguish enzootic strains of subtype i-d from those of i-e. | strains of venezuelan encephalitis virus isolated from enzootic habitats during interepizootic periods in middle america and northern south america can be distinguished from each other antigenically by hemagglutination inhibition. this test has provided the basis for the classification of these virus strains into subtypes i-e and i-d, respectively. virus strains of these two subtypes have been found to differ profoundly with respect to virulence for english short hair guinea pigs. studies are de ... | 1985 | 3893103 |
| ph-induced alterations in the fusogenic spike protein of semliki forest virus. | the spike glycoproteins of semliki forest virus mediate membrane fusion between the viral envelope and cholesterol-containing target membranes under conditions of mildly acidic ph (ph less than 6.2). the fusion reaction is critical for the infectious cycle, catalyzing virus penetration from the acidic endosome compartment. to define the role of the viral spike glycoproteins in the fusion reaction, conformational changes in the spikes at acid ph were studied using protease digestion and binding a ... | 1985 | 3905823 |
| transcription and translation of foreign genes in bacillus subtilis by the aid of a secretion vector. | expression levels of bacillus amyloliquefaciens alpha-amylase, escherichia coli tem-beta-lactamase, and semliki forest virus glycoprotein e1 genes were compared in bacillus subtilis. all three model genes were expressed by using a secretion vector, constructed by joining the b. amyloliquefaciens alpha-amylase promoter and signal sequence with plasmid pub110 (i. palva, m. sarvas, p. lehtovaara, m. sibakov, and l.kääriäinen, proc. natl. acad. sci. u.s.a. 79:5582-5586, 1982). when transformed b. su ... | 1985 | 3920200 |
| secretion of semliki forest virus membrane glycoprotein e1 from bacillus subtilis. | the gene coding for the semliki forest virus (sfv) membrane protein e1 was joined to a secretion vector containing the promoter and signal sequence regions of the alpha-amylase gene from bacillus amyloliquefaciens. to facilitate secretion, the regions coding for the n-terminal signal peptide (the 6k protein) and the c-terminal hydrophobic transmembrane domain of the e1 gene were deleted. after transformation into b. subtilis, e1 was shown by immunoblotting to be expressed at a low level (about 0 ... | 1985 | 3920841 |
| determination of inhibitory concentrations of antiviral agents in cell culture by use of an enzyme immunoassay with virus-specific, peroxidase-labeled monoclonal antibodies. | an enzyme immunoassay (eia) to determine 50% inhibitory concentrations of drugs which suppress semliki forest virus replication is described. inhibition of virus replication was measured in l-cells, seeded as monolayers in 96-well plates by use of horseradish peroxidase-labeled monoclonal antibodies directed against the e1 glycoprotein of semliki forest virus. the antiviral agents tested were cycloheximide, tunicamycin, nh4cl, and disodium cromoglycate. the 50% inhibitory concentration of these ... | 1985 | 3925876 |
| changes in glycosylation of rubella virus envelope proteins during maturation. | tunicamycin treatment of radioactively labelled infected vero cells followed by electrophoresis in polyacrylamide gels showed that the mol. wt. of the putative polypeptide backbones of gp59(e1) and gp43(e2), the intracellular counterparts to the envelope proteins e1 and e2 of rubella virus, were 53000 and 34000, respectively. two possible intermediates in the glycosylation of gp43(e2) were also identified. [3h]mannose-labelled e1, e2, gp59(e1) and gp43(e2) were digested with pronase and the glyc ... | 1985 | 3968538 |
| acute phase response of serum amyloid a protein and c reactive protein to the common cold and influenza. | c reactive protein (crp) and serum amyloid a protein (saa) are sensitive and rapid acute phase reactants, and their measurement for monitoring inflammatory disease and assessing the prognosis in secondary amyloidosis is gaining widespread acceptance. the changes in these proteins in eight subjects suffering from natural colds, 15 subjects with experimentally induced colds (rhinoviruses e1, 3, 9, 14, or 31), and eight with experimentally induced influenza (a/eng/40/83) were studied. saa concentra ... | 1985 | 3973057 |
| antibody response to individual rubella virus proteins in congenital and other rubella virus infections. | serum samples from patients with various forms of rubella virus infection were tested for antibodies to each of three viral structural proteins by radioimmunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. in most sera antibody to e1 protein was the predominant species. sera from patients with congenital rubella syndrome, however, contained significantly more e2 antibody relative to e1 antibody than did sera from other rubella patients. | 1985 | 3980696 |
| genetic and antigenic variations among geographical isolates of sindbis virus. | the genetic and antigenic variation in 12 sindbis (sin) virus isolates from four zoogeographic regions (paleoarctic, ethiopian, oriental and australian) has been examined at a molecular level. rnase t1 oligonucleotide fingerprinting of genomic rna from sin isolates revealed that the primary structure of the rna from viruses from each zoogeographic region was unique. the e1 and e2 glycoproteins and the capsid protein of two isolates from each zoogeographic region were compared by tryptic peptide ... | 1985 | 3981136 |
| properties of rat cells transformed by dna plasmids containing adenovirus type 12 e1 dna or specific fragments of the e1 region: comparison of transforming frequencies. | in this paper, we describe for the first time the transformation of normal rat cells by dna equivalent to adenovirus type 12 early region 1 (e1a). this dna was 30-fold less efficient at transformation than dna encoding the entire e1 region. those established lines expressing a full complement of adenovirus type 12 e1 proteins were phenotypically indistinguishable from adenovirus type 12 virus-transformed cell lines. however, cell lines produced by plasmids carrying subgenomic fragments of e1 dna ... | 1985 | 3986802 |
| effects of monovalent cations on semliki forest virus entry into bhk-21 cells. | infection of mammalian cells with semliki forest virus requires the endocytosis of the virus, its delivery to prelysosomal endosomes, and fusion of the viral envelope with the endosome membrane. previous studies have indicated that the low endosomal ph triggers a conformational change in the viral spike glycoproteins rendering them fusogenic. in this paper, we demonstrate an additional factor(s) which regulates virus fusion in endosomes. we found that semliki forest virus is unable to penetrate ... | 1985 | 3988769 |
| selective reactivity of antibodies to human immunoglobulins g, m, and a with rubella virus proteins. | proteins of purified rubella virus were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to nitrocellulose, and immunoblotted with human sera and immunoglobulin class heavy-chain-specific peroxidase conjugates. the levels of rubella antibodies in these sera were predetermined by the radial hemolysis test, the density gradient centrifugation method for immunoglobulin m (igm) antibodies, and igg-, igm-, and iga-specific enzyme immunoassays. in immunoblotting, rub ... | 1985 | 3998114 |
| a model of the structural organization of rubella virions. | rubella virus contains three major structural polypeptides designated e1, e2, and c with molecular weights of 62,000, 47,000-54,000 (a complex), and 38,000, respectively, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reduced conditions. limited-digest peptide maps confirm that each of these polypeptides is distinct and the e2 is a series of three closely related glycopolypeptides. both e1 and e2 are glycosylated and covalently incorporate [3h]palmitic acid. enz ... | 1985 | 4001720 |
| molecular and antigenic characteristics and synthesis of rubella virus structural proteins. | the molecular and antigenic properties and synthesis of the structural proteins as well as the virus-specific rnas of rubella virus were analyzed. virions contain three major polypeptides--e1 (relative molecular weight [mr] 58,000), e2 (mr 42,000-47,000), and c (mr 33,000). e1 and e2 are glycosylated and located externally on the viral membrane. c is associated with the genomic rna to form the nucleocapsid. e2 occurs in two forms, e2a and e2b; the protein moieties of the two are indistinguishabl ... | 1985 | 4001721 |
| structure and function of the rubella virus proteins. | rubella virus strain hpv-77 contains three structural polypeptides. the nucleocapsid is constructed with the c polypeptide chain, which has a molecular weight of 30,000. the envelope proteins are constructed with two glycopolypeptides; the e1 glycopolypeptide has a molecular weight of 63,000, and the e2 glycopolypeptide has a molecular weight of 45,000-48,000. the nucleocapsid capsomere is approximately 6.2s, has a molecular weight of 130,000, and consists of two disulfide-linked dimers of the c ... | 1985 | 4001722 |
| virus persistence in groundwater. | more than 50% of the outbreaks of waterborne disease in the united states are due to the consumption of contaminated groundwater. an estimated 65% of the cases in these outbreaks are caused by enteric viruses. little, however, is known about the persistence of viruses in groundwater. the purpose of this study was to determine whether measurable chemical and physical factors correlate with virus survival in groundwater. groundwater samples were obtained from 11 sites throughout the united states. ... | 1985 | 4004211 |
| in vitro synthesis of the gene coding for the glycoprotein e1 of sindbis virus. | ds cdna of the 42s virionic rna of sindbis virus has been synthesized and cloned in the plasmid pbr 322. restriction map analysis and hybridization studies show that two clones cover the 3' end non coding region of the rna, the whole membrane glycoprotein e1 and a peptide of mw 6,000 daltons. the use of these clones in experiments of gene expression in mammalian cell is discussed. | 1985 | 4010526 |
| properties of monoclonal antibodies against glycoproteins of western equine encephalitis virus. | to analyze the biological activities of the alphavirus glycoproteins, eight different monoclonal antibodies against the two glycoproteins of western equine encephalitis virus were isolated. five of the eight monoclonal antibodies were shown to be specific for e1 and three for e2 protein by an enzyme-linked immunosorbent assay and by radioimmunoprecipitation. three of the five anti-e1 and all of the anti-e2 monoclonal antibodies inhibited hemagglutination by purified virions. one anti-e1 and two ... | 1985 | 4020970 |
| expression of sindbis virus structural proteins via recombinant vaccinia virus: synthesis, processing, and incorporation into mature sindbis virions. | we have obtained a vaccinia virus recombinant which contains a complete cdna copy of the 26s rna of sindbis virus within the thymidine kinase gene of the vaccinia virus genome. this recombinant constitutively transcribed the sindbis sequences throughout the infectious cycle, reflecting the dual early-late vaccinia promoter used in this construction. the sindbis-derived transcripts were translationally active, giving rise to both precursor and mature structural proteins of sindbis virus, includin ... | 1985 | 4032536 |
| pattern of glycosylation of sindbis virus envelope proteins synthesized in hamster and chicken cells. | the tryptic glycopeptides of the sindbis virus envelope glycoproteins e1 and e2 grown in bhk and chick cells were purified by gel filtration followed by high-pressure liquid chromatography. each of the purified glycopeptides was analyzed by n-terminal sequencing to identify from which of the potential glycosylation sites it was derived. the type of oligosaccharide chain attached to each glycopeptide was determined from gel filtration analysis of the pronase-digested glycopeptides, and the relati ... | 1985 | 4060569 |
| pleiotypic control by adenosine 3':5'-cyclic monophosphate: a model for growth control in animal cells. | the effects of serum deprivation on several general cellular biochemical processes ("pleiotypic response") related to the growth of normal fibroblasts can be mimicked by treatment of these cells with prostaglandin e(1) in the presence of serum. n(6),o(2)'-dibutyryl adenosine 3':5'-cyclic monophosphate and theophylline inhibit the membrane transport processes without much effect on other pleiotypic reactions such as overall protein and rna synthesis and protein degradation. the amount of intracel ... | 1973 | 4351178 |
| formation of sindbis virus proteins: identification of a precursor for one of the envelope proteins. | exposure of sindbis virus-infected chicken embryo cells to a short pulse of radioactive amino acids revealed the formation of primarily three proteins: the nucleocapsid (c) of the virus, one of the viral envelope proteins (e1), and a glycoprotein that did not appear in the virion. this third protein (pe2) has now been identified as a precursor of the other viral envelope protein (e2) on the basis of two observations: (i) the simultaneous disappearance of radioactive pe2 and appearance of labeled ... | 1972 | 4673887 |
| the growth of echovirus 1 in hep-2 cells treated with antibody to the host cells. | 1969 | 5803272 | |
| physical state and transcription of the cottontail rabbit papillomavirus genome in warts and transplantable vx2 and vx7 carcinomas of domestic rabbits. | the physical state and the transcription of the genome of cottontail rabbit papillomavirus (crpv) in non-virus-producing warts and in the vx2 and vx7 transplantable carcinomas of domestic rabbits were compared. the crpv dna present in vx2 and vx7 carcinomas (10 to 20 and 100 to 200 genome equivalents per diploid cell, respectively) was found to be entirely integrated into the cellular dna, most probably as head-to-tail tandem repeats, in contrast to warts, in which viral dna (10 to 100 copies pe ... | 1984 | 6086962 |
| a common function for polyoma virus large-t and papillomavirus e1 proteins? | nucleotide sequencing has revealed a common genetic organization for three papillomaviruses: bpv-1 (bovine papillomavirus type 1), hpv-1 (human papillomavirus type 1a) and hpv-6 (human papillomavirus type 6b). several open reading frames, corresponding to as yet uncharacterized proteins, were observed in these genomes in the region that is required for oncogenic transformation by bpv-1 and for plasmidial maintenance of its genome. the longest of these frames, e1, is also the most conserved betwe ... | 1984 | 6090931 |
| dna-binding proteins of chick embryo lethal orphan virus: lack of complementation between early proteins of avian and human adenoviruses. | chick cells infected by chick embryo lethal orphan (celo) virus (fowl adenovirus type 1) contained four prominent virus-specific, structurally related dna-binding proteins with mol. wt. of 74k, 64k, 56k, 52k, and two minor forms. the celo virus dna-binding proteins were phosphorylated, delayed-early nuclear proteins. celo virus early proteins were expressed in bhk cells, but did not complement human adenovirus type 5 mutants with lesions e1a, e2a or e2b. moreover, celo virus dna-binding proteins ... | 1984 | 6092525 |
| sequence homology between the large tumor antigen of polyoma viruses and the putative e1 protein of papilloma viruses. | the large tumor antigen of simian virus 40, mouse polyoma virus, and human bk virus is compared to the e1 protein of human and bovine papilloma viruses. it is suggested that large t and e1 are evolutionarily related and that the region of major homology forms part of an alpha/beta domain involved in nucleotide binding. | 1984 | 6093371 |
| the transfer of myristic and other fatty acids on lipid and viral protein acceptors in cultured cells infected with semliki forest and influenza virus. | [3h]myristic and [3h]palmitic acid were compared as tracers for the fatty acylation of cellular lipids and viral glycoproteins in chicken embryo cells infected with fowl plague and semliki forest virus (sfv). both of these substrates are incorporated into glycerolipids to a similar extent, whereas sphingolipids show much higher levels of palmitate than myristate after a 20 h labeling period. both fatty acid species were found to be subject to metabolic conversions into longer chain fatty acids y ... | 1984 | 6094180 |
| agarose isoelectrofocusing of intact virions. | a convenient and accurate method for determining the isoelectric points of intact virions is described. tritium-labeled poliovirus 1 (strains brunhilde and lsc-2) and echovirus 1 (isolates v239, v248, v212, r115 and 4ch-1) were successfully focused into sharp bands at their respective isoelectric points using a thin-layer agarose isoelectric focusing system. in situ detection of labeled virus bands in the agarose was by fluorography. freezing and thawing of virus samples prior to isoelectric foc ... | 1984 | 6094606 |
| gene order of translation of the flavivirus kunjin: further evidence of internal initiation in vivo. | the rates of inactivation of synthesis of individual virus-specified proteins by ultraviolet radiation provided an estimate of the target sizes of individual viral genes. in a control experiment with semliki forest virus, the genes for the structural proteins mapped in the known sequence 5' c-pe2-e1 3', and in accordance with initiation of translation from a single site on 26-s mrna. under the same conditions, the inactivation of synthesis of seven kunjin virus-specified proteins also followed f ... | 1984 | 6099663 |
| effect of different passage histories of infectious bronchitis virus on the sensitivity to inhibitors in chick serum and their removal by trypsin. | sensitivity of the beaudette strain of infectious bronchitis virus (ibv) to non-antibody inhibitors in neutralization tests depended on the passage history of the virus. the chick embryo kidney cell-adapted (e71 cek11) virus was the most sensitive, but after one chick embryo (ce) passage (e71 cek11 e1), this virus showed reversion to the sensitivity of the parent virus (e71). ibv inhibitors in chicken serum could be removed by treatment with trypsin but not with phospholipase c. | 1984 | 6147998 |
| a comparison of new world alphaviruses in the western equine encephalomyelitis complex by immunochemical and oligonucleotide fingerprint techniques. | we have examined the molecular basis for the observed antigenic differences between isolates of western equine encephalomyelitis (wee) virus and those of a serologically related alphavirus from the eastern united states designated highlands j (hj). the structural proteins of wee virus isolates have mol. wt. of 55 x 10(3) (e1), 47 x 10(3) (e2) and 33 x 10(3) for the nucleocapsid. the e1 glycoprotein had an isoelectric point (pi) of 6.4 and induced haemagglutination-inhibiting (hi) antibody which ... | 1980 | 6154128 |
| cross-reactive, cell-associated antigen on l929 cells infected with temperature-sensitive mutants of sindbis virus. | temperature-sensitive (ts) mutants of sindbis virus (sin) were used to aid in the identification of alphavirus cross-reactive proteins on the surface of infected cells by antibody-dependent, complement-mediated cytolysis. antisera prepared in rabbits against purified sin or semliki forest viruses were highly cytotoxic for cells infected with wild-type sin and for cells infected at the permissive temperature with maturation-defective, ts mutants of sin belonging to several distinct complementatio ... | 1982 | 6177636 |
| identification by monoclonal antibodies of a new epitope in the glycoprotein complex of sindbis virus. | monoclonal antibodies against a deletion mutant of sindbis virus were produced and characterized in order to determine the fine mapping and functional activities of single viral epitopes. all monoclonal antibodies so far tested showed a certain degree of reciprocal competition and were directed against an antigenic determinant which was present only on the undissociated complex of the e1 and e2 glycoproteins. a biological assay measuring viral haemagglutination showed no decrease in the titre of ... | 1983 | 6190835 |
| solubilization and immune-detection of beta-galactosidase hybrid proteins carrying foreign antigenic determinants. | three dna fragments representing almost the entire e1 gene of semliki forest virus (sfv) were inserted into a cro-lacz expression vector by oligo dc.oligo dg tailing. fragments inserted close to the 5' end of the lacz gene gave rise to hybrid proteins which were rapidly degraded. insertion of the same fragments at the 3' end, however, resulted in the synthesis of stable hybrid proteins which precipitated in an insoluble form within the bacteria. insufficient hybrid protein was soluble to allow d ... | 1983 | 6191278 |
| heterogeneity of a human isolate of coxsackie b4: biological differences. | evidence is presented to demonstrate existence of virion heterogeneity within the human isolate, edwards, of coxsackievirus b4 (cb4-edw). three virion types (e1, e2 and e3) were cloned by repeated plaque purification of cb4-edw and then all were compared relative to their effects on the pancreas of mice during acute infection. seventy-two hours post-infection blood glucose, plasma amylase and insulin levels were monitored in mice of the swr/j strain (previously classified susceptible to other di ... | 1983 | 6193205 |
| protective monoclonal antibodies define maturational and ph-dependent antigenic changes in sindbis virus e1 glycoprotein. | monoclonal (mc) antibodies specific for either the ei or e2 glycoproteins of sindbis virus (sin) were used to probe for differences in the surface topography of sin epitopes between infected cells and mature virions. employing an enzyme-linked immunosorbent assay (elisa) in which binding of individual peroxidase-labeled mc antibodies to immobilized (solid-phase) detergent-disrupted sin was inhibited specifically by one or more unlabeled antibodies, viral epitopes could be grouped into six spatia ... | 1983 | 6195815 |
| topographical mapping of epitopes on the glycoproteins of murine hepatitis virus-4 (strain jhm): correlation with biological activities. | monoclonal hybridoma antibodies (mab) of defined polypeptide specificity and biological activity were used in a competition binding assay to identify antibody binding sites (epitopes) on the glycoproteins of murine hepatitis virus-4 strain jhm (mhv-4). individual mab were labeled with horseradish peroxidase (hrp) and used as probes in a competition enzyme immunoassay (eia). four topographically distinct antigenic sites were detected on the e2 glycoprotein of mhv-4. antibodies reacting with these ... | 1984 | 6199888 |
| murine hepatitis virus-4 (strain jhm)-induced neurologic disease is modulated in vivo by monoclonal antibody. | monoclonal hybridoma antibodies directed against the polypeptides of murine hepatitis virus-4 (jhm strain) were tested for their ability to alter the course of a normally lethal intracerebral virus challenge. three monoclonal antibodies directed against two distinct epitopes on the e2 glycoprotein of mhv-4 protected mice against lethal virus challenge and converted the infection from fatal encephalomyelitis to demyelination. a single neutralizing antibody directed against a third epitope on e2 a ... | 1984 | 6199889 |
| antiviral activity of a thymic factor in experimental viral infections. i. thymic hormonal effect on survival, interferon production and nk cell activity in mengo virus-infected mice. | a partially purified thymic factor, thymostimulin (ts), significantly increased the survival rate of adult, immune-intact mice infected with the neurotropic mengo virus. ts treatment was begun after virus inoculation by daily i.p. injections. in untreated c57bl/6 mice, ld50 was reached with 1 x 10(4) pfu, but 10-fold more virus (i.e., 1 x 10(5) pfu) was needed to reach ld50 in ts-treated animals. ts effect on survival, though, could be observed with several virus doses (1 x 10(3) to 1 x 10(6) pf ... | 1984 | 6202776 |
| identification of distinct antigenic determinants on semliki forest virus by using monoclonal antibodies with different antiviral activities. | fifteen monoclonal antibodies (mas) directed against either the e1 or e2 glycoprotein of semliki forest virus (sfv) were characterized by immunoglobulin subclass, pi traject, hemagglutination inhibition, neutralization of infectious virus, and protection against virulent infection in mice. all mas except um8.4 (immunoglobulin m [igm]) belonged to various subclasses of igg and predominantly to igg2a, but all were unique as indicated by their banding patterns in isoelectric focusing. competitive b ... | 1984 | 6208379 |
| effect of prostaglandins and cyclic adenosine 3',5'-monophosphate modulators on herpes simplex virus growth and interferon response in human cells. | mechanisms whereby prostaglandins and other cyclic adenosine 3',5'-monophosphate (camp) modulators might enhance the growth of herpes simplex virus (hsv) in human skin fibroblasts were explored. prostaglandins a1, b1, e1, e2, and f2 alpha, as well as isoproterenol, imidazole, carbamylcholine, and dibutyryl camp had no effect on hsv growth. on the other hand, the phosphodiesterase inhibitors 1-methyl-3-isobutylxanthine and theophylline delayed the growth, suppressed the cell-to-cell spread, but i ... | 1980 | 6244226 |
| isolation of coronavirus envelope glycoproteins and interaction with the viral nucleocapsid. | the two envelope glycoproteins and the viral nucleocapsid of the coronavirus a59 were isolated by solubilization of the viral membrane with nonidet p-40 at 4 degrees c followed by sucrose density gradient sedimentation. isolated e2 consisted of rosettes of peplomers, whereas e1, the membrane glycoprotein, was irregular and amorphous. under certain conditions significant interactions occurred between components of nonidet p-40-disrupted virions. incubation of the nonidet p-40-disrupted virus at 3 ... | 1980 | 6245243 |
| effect of membrane phospholipid composition changes on adenylate cyclase activity in normal and rous-sarcoma-transformed chicken embryo fibroblasts. | adenylate cyclase specific activities in membranes isolated from chicken embryo fibroblasts transformed by rous sarcoma virus are significantly lower than the specific activity of the enzyme in normal membranes. since normal and transformed membranes have different phospholipid and fatty acid compositions, adenylate cyclase activities were examined in normal and transformed membranes which had been supplemented with polar head groups or fatty acids. basal, fluoride, and prostaglandin e1-stimulat ... | 1980 | 6245707 |
| influence of estuarine sediment on virus survival under field conditions. | the survival of poliovirus 1 (lsc) and echovirus 1 (farouk) in estuarine water and sediment was studied in galveston bay, texas. viruses were suspended in estuarine water and sediment both in dialysis tubing and in chambers constructed with polycarbonate membrane walls. virus inactivation rates in seawater were similar in both types of chambers. virus adsorption to sediment greatly increased survival time. the time required to inactivate 99% (t-99) of poliovirus increased from 1.4 days in seawat ... | 1980 | 6246838 |
| endogenous synthesis of prostaglandins e1 and i2 in 3t3 fibroblasts transformed by polyoma virus. effects on adenosine 3':5'-monophosphate production. | prostaglandins (pg)e1, e2 and i2 were produced by polyoma virus transformed (py) 3t3 fibroblasts. the levels of pge1, pge2 and 6-keto-pgf1 alpha (degradation product of pgi2) were 22.7, 225 and 33.2 ng/ml medium, respectively, 72 h after medium change. the stimulatory potencies of exogenous pge1, pge2 and pgi2 on adenosine 3':5'-monophosphate (cyclic amp) formation were similar. therefore, the prostaglandin mediated increase in cyclic amp levels observed during growth of these cells (claesson, h ... | 1980 | 6247743 |
| prostaglandin e1 binding and adenylate cyclase activation in normal and transformed fibroblasts. | the binding of [3h]prostaglandin e1 to membranes of clones of normal rat kidney fibroblasts (nrk cells) has been measured. cell lines that responded to prostaglandin e1, such as nrk and nrk transformed with schmitt-ruppin strain of rous sarcoma virus (sr-nrk cells), have a high affinity prostaglandin e1 binding site. murine-sarcoma-virus-transformed lines of nrk cells are unresponsive to prostaglandin e1 and have reduced prostaglandin e1 binding exposure of cells to prostaglandin e1 results both ... | 1980 | 6248120 |
| use of cell fusion techniques to probe the mechanism of catecholamine-induced desensitization of adenylate cyclase in frog erythrocytes. | the catecholamine-sensitive adenylate cyclase system appears to be comprised of at least three components; the beta-adrenergic receptor (r component), the catalytic unit of adenylate cyclase (c component) and a nucleotide regulatory protein (n component), responsible for mediating the effects of guanine nucleotides on the system. cell fusion techniques were used to investigate the role of these three components in the process of homologous desensitization in the frog erythrocyte. dicyclohexylcar ... | 1980 | 6251915 |
| increased cyclic amp content directly correlated with morphological transformation of cells infected with a temperature-sensitive mutant of mouse sarcoma virus. | normal rat kidney cells infected with a cold-sensitive mutant of mouse sarcoma virus [nrk(msv-lb)] morphologically transform when exposed to adenosine 3':5' cyclic monophosphate (camp) at the restrictive temperature. the camp-induced morphological changes occur rapidly and are reversible. agents capable of elevating endogenous levels of camp [prostaglandin e1 (pge1) and cholera toxin (ct)] induced morphological transformation of nrk(msv-lb) cells at the restrictive temperature that was concentra ... | 1980 | 6252097 |
| reduced granulocyte response to isoproterenol, histamine, and prostaglandin e1 after in vitro incubation with rhinovirus 16. | rhinovirus respiratory infections have been frequently associated with the precipitation of an asthma attack. as an explanation for virus-provoked asthma, it has been proposed that viruses or their products may alter beta-adrenergic responsiveness. isolated human granulocytes have provided an in vitro study model for this problem. granulocyte release of the lysosomal enzyme beta-glucuronidase (bg) occurred after incubation with complement-activated zymosan particles, and this release was inhibit ... | 1980 | 6254414 |
| subcellular action of neocarzinostatin. intracellular incorporation, dna breakdown and cytotoxicity. | the subcellular site of action of a proteinaceous antitumor antibiotic neocarzinostatin (ncs) was studied using normal human lymphocytes, epstein-barr virus transformed lymphoblastoid cells, osmotically burst lymphoblastoid cells, and colicin e1 plasmid dna. the rate of dna strand break in these different types of dna was found to be in the following order: colicin dna > burst cell dna > lymphoblastoid cell dna > normal lymphocyte dna. furthermore, fluorescence microscopy revealed that lymphobla ... | 1980 | 6256337 |
| effects of environmental variables and soil characteristics on virus survival in soil. | because of the increasing emphasis placed upon land application as a means of wastewater disposal, it is important to evaluate the influences of different factors upon virus survival in soil. the objective of this study was to measure the effects of various environmental variables on virus persistence. test samples of soil were placed in vials, and the soil was wetted with suspensions of virus in either distilled water, unchlorinated secondary sewage effluent, or mixtures of effluent and water. ... | 1980 | 6257161 |
| effects of beta adrenergic agents and prostaglandin e1 on erythroid colony (cfu-e) growth and cyclic amp formation in friend erythroleukemic cells. | the formation of erythroid colonies from bone marrow and spleen cells infected with the polycythemic strain of the friend virus (fv-p) was characterized in an in vitro methyl cellulose colony-forming system in response to prostaglandin e1 and the beta-2 adrenergic agonist, albuterol. both drugs markedly inhibited the formation of cfu-e colonies of fv-p-infected bone marrow and spleen in the absence or presence of erythropoietin. the albuterol-mediated inhibition of cfu-e colonies (fv-p-infected) ... | 1980 | 6257732 |
| survival of enteroviruses in rapid-infiltration basins during the land application of wastewater. | the downward migration through soil of seeded poliovirus type 1 and echovirus type 1 and of naturally occurring enteroviruses during infiltration of sewage effluent through rapid-infiltration basins was investigated. after 5 days of flooding, the amount of seeded poliovirus type 1 that had migrated 5 to 10 cm downward through the soil profile was found to be 11% of that remaining at the initial burial depth. the amount of echovirus type 1 determined to have moved an equal distance was at least 1 ... | 1980 | 6258471 |
| fluorescence photobleaching recovery measurements reveal differences in envelopment of sindbis and vesicular stomatitis viruses. | fluorescence photobleaching recovery (fpr) measurements of virus glycoproteins on the surfaces of cells infected with vesicular stomatitis virus (vsv) and sindbis virus showed that the vsv glycoprotein (g) remained mobile throughout the infectious cycle, whereas sindbis virus glycoproteins (e1, e2) were partially mobile early after infection and immobile at later times when greater amounts of these proteins were on the cell surface. a highly mobile fraction of sindbis virus glycoproteins was det ... | 1981 | 6258803 |
| distribution of virus structural proteins and protein-protein interactions in plasma membrane of baby hamster kidney cells infected with sindbis or vesicular stomatitis virus. | the plasma membrane of baby hamster kidney (bhk-21) cells infected with either sindbis or vesicular stomatitis virus was isolated by a technique involving the ingestion of latex beads by the cells. plasma membrane isolated from sindbis virus-infected cells contained only one (e1) of the three (e1, e2, and c) structural proteins of this virus. when the latex beads were pretreated with either polylysine or deae-dextran, plasma membrane obtained from sindbis virus-infected cells contained all three ... | 1980 | 6261249 |
| uptake and survival of enteric viruses in the blue crab, callinectes sapidus. | uptake of poliovirus 1 by the blue crab, callinectes sapidus, was measured to assess the likelihood of contamination by human enteric viruses. virus was found in all parts of the crab within 2 h after the crab was placed in contaminated artificial seawater. the highest concentrations of virus were found in the hemolymph and digestive tract, but the meat also contained virus. the concentration of virus in the crabs was generally less than in the surrounding water. changes in salinity did not subs ... | 1981 | 6261683 |
| virion polypeptide heterogeneity among virulent and avirulent strains of eastern equine encephalitis (eee) virus. | comparative analysis of structural virion polypeptides of 24 selected eee virus strains, representing north and south american types, was performed by one-dimensional discontinuous sodium dodecyl sulfate (sds)-polyacrylamide-gel electrophoresis (page). the structural proteins of different eee virus isolates, resolved by this method, exhibited mol.wts. values in the range of 57-60 x 10(3) for (e-1), 51-54 x 10(3) for (e-2) and 35-38 x 10(3) daltons for the core (np) nucleocapsid. the exception wa ... | 1981 | 6268022 |
| early interaction between mouse hepatitis virus 3 and cells. | the interaction between mouse hepatitis virus 3 (mhv3) and cells was studied in order to investigate whether or not early events occurring after infection could be involved in the difference in virus replication seen between mouse strains with different genetic sensitivities to mhv3 infection. kinetic data showed that mhv3 uptake by both macrophages and l cells was time- and temperature-dependent. in addition, treatment of cells with cytochalasin b or prostaglandin e1, prior to virus infection, ... | 1981 | 6275022 |
| viral protein synthesis in mouse hepatitis virus strain a59-infected cells: effect of tunicamycin. | we identified eight protein species in virions of mouse hepatitis virus strain a59. based on their sizes, prosthetic groups, and locations in virions, these proteins were designated gp180/e2, gp90/e2, pp54/n, gp26.5/e1, gp25.5/e1, p24/e1, p22/x, and p14.5/y. the positions of the last two proteins in virions are not known. host protein synthesis in sac(-) cells infected with mouse hepatitis virus strain a59 was inhibited, and the following novel proteins appeared: gp150, gp90, p54, gp26.5, gp25.5 ... | 1981 | 6275093 |
| a cascade of adenovirus early functions is required for expression of adeno-associated virus. | one measurable biological activity of early adenovirus genes is their ability to promote growth of the defective adeno-associated virus, aav. we have identified an ordered sequence of communications among the early genes of adenovirus type 2 (ad2) that results in expression of the helper activity. we purified dna fragments and mrnas corresponding to early ad2 regions e1, e2a, e3 and e4 and injected them via glass capillaries into aav-infected cells. dnas were placed in the nucleus, mrnas in the ... | 1981 | 6276019 |
| roles of polyamines in the replication of animal viruses. | several animal viruses are known to contain significant amounts of polyamines but so far the function of these viral components is poorly understood. in this study the role of polyamines in the replication of two different types of viruses, herpes simplex virus type 2 and semliki forest virus (sfv) has been investigated. purified sfv was found to contain fairly small amounts of polyamines, sufficient to neutralize only about 3% of viral nucleic acid phosphate, i.e., 1/20 of that found in herpes ... | 1981 | 6279979 |
| properties of monoclonal antibodies directed against the glycoproteins of sindbis virus. | four monoclonal antibodies that react with sindbis virus glycoproteins have been examined for (i) their effects on virus infectivity, (ii) their ability to recognize conformational changes in glycoprotein structure, and (iii) their cross-reaction with several different alphaviruses. two of the monoclonal antibodies reacted with the native forms of the e1 glycoprotein but did not neutralize virus infectivity. one of the anti-e1 antibodies formed an infectious virus-antibody complex. the other two ... | 1982 | 6281377 |
| inhibition of sindbis virus maturation after treatment of infected cells with trypsin. | brief treatment of sindbis virus-infected bhk-21 or vero cells with low concentrations of trypsin irreversibly blocked further production of progeny virions after removal of the enzyme. the inhibitory effects of the trypsin treatment could only be demonstrated in cells in which virus infection was established; optimal inhibition occurred at ca. 3 h postinfection. production of virus structural proteins pe2, e1, and c occurred at normal levels in inhibited cells. pe2 and e1 were also transported ... | 1982 | 6281478 |
| differential effect of prostaglandins and other products of arachidonic acid metabolism on measles virus replication in vero cells. | the influence of cyclic adenosine 3', 5'-monophosphate (camp) and prostaglandin (pg), e1, e2, f2 alpha, a2 and thromboxane b2 (txb2) and measles virus infection was investigated. addition of pge1, e2 and camp (10(-3)-10(-)8m) inhibited measles virus replication in vero cells. txb2 and pga2 enhanced replication. cytotoxic effects were not observed. inhibition of infectious titers (98%) was most pronounced when agents were present throughout replication. treated cells exhibited hemadsorbing antige ... | 1982 | 6281810 |
| fv-1 determinants in xenotropic murine leukemia viruses studied with biological assay systems: isolation of xenotropic virus with n-tropic fv-1 activity in the cryptic form. | by a biological assay system using phenotypically mixed ecotropic and xenotropic murine leukemia viruses, we investigated whether in the virions of a xenotropic virus there is n- or b-tropic fv-1 determinant in active form. the existence of n-tropic fv-1 determinant was demonstrated in sl-xt-1 xenotropic virus isolated from the spleen of a 3-month-old sl mouse, and the n-tropic fv-1 tropism was confirmed by analysis of the phenotypically mixed viruses harvested from clonal sc-1 cells doubly infe ... | 1982 | 6283153 |
| use of a hybrid infectivity assay to analyze primary transcription of temperature-sensitive mutants of the new jersey serotype of vesicular stomatitis virus. | a hybrid infectivity assay specific for primary transcription was developed to analyze the production of functional mrnas by vesicular stomatitis virus. a template prepared from wild-type virions of the new jersey serotype of vesicular stomatitis virus was reconstituted with rna polymerase proteins from the wild type or temperature-sensitive mutants, and the in vivo temperature sensitivity of the polymerase was determined by infectivity assay. the data demonstrate that the new jersey temperature ... | 1982 | 6287014 |
| loss and restoration of glucagon receptors and responsiveness in a transformed kidney cell line. | a kidney cell line (mdck) retains an adenylate cyclase system sensitive to glucagon, vasopressin, isoproterenol and prostaglandin e1. the stimulatory effect of glucagon on camp production was selectively lost in a cloned line derived from mdck cells transformed by harvey murine sarcoma virus. sensitivity to glucagon was largely restored by treatment of the transformed cells with prostaglandin e1 or butyrate. loss and reappearance of glucagon receptors seemed to be responsible for the observation ... | 1982 | 6291963 |
| cell-free translation of murine coronavirus rna. | the coding assignments of the intracellular murine hepatitis virus-specific subgenomic rna species and murine hepatitis virion rna have been investigated by cell-free translation. the six murine hepatitis virus-specific subgenomic rnas were partially purified by agarose gel electrophoresis and translated in an mrna-dependent rabbit reticulocyte lysate, and the cell-free translation products were characterized by gel electrophoresis, immunoprecipitation, and tryptic peptide mapping. these studies ... | 1982 | 6292469 |
| assembly of vesicular stomatitis virus: distribution of the glycoprotein on the surface of infected cells. | this study demonstrates that the glycoprotein of vesicular stomatitis virus clusters in the plasma membrane of infected chinese hamster lung cells during morphogenesis and suggests that viral nucleocapsids are required for this clustering. a mutant virus (ts e-1) which is temperature sensitive for the synthesis of viral nucleocapsids but not viral membrane proteins was used. the surface distribution of the viral glycoprotein in cells infected by this virus was determined by a specific indirect i ... | 1982 | 6294321 |
| coronavirus proteins: structure and function of the oligosaccharides of the avian infectious bronchitis virus glycoproteins. | the recent finding that the e1 glycoproteins of murine coronaviruses contain only o-linked oligosaccharides suggested that this unusual modification might be a distinguishing feature of coronaviruses and might play an essential role in the life cycle of this family of viruses. to examine these possibilities, we analyzed the oligosaccharide moieties of the membrane proteins of the avian coronavirus infectious bronchitis virus. in addition, we determined the effect of inhibiting the glycosylation ... | 1982 | 6294330 |
| diversity within a human isolate of coxsackie b4: relationship to viral-induced diabetes. | the ability of different strains of a single virus type to produce different pathogenic expressions is well documented within the picornavirus group. coxsackievirus, group b, type 4 (cb4) has been associated with viral-induced diabetes in man, but expression of its potential to induce diabetes in experimental animals is variable. evidence is presented here for one of the primary sources of this variability that could explain resulting contradictory reports offered in support or rejection of its ... | 1983 | 6300315 |
| analysis of virus-specific mrnas present in cells transformed with restriction fragments of adenovirus type 5 dna. | adenovirus type 5 (ad5) mrnas present in cells transformed with left-terminal ad5 dna fragments (xhoi-c, 0 to 15.5%; hindiii-g, 0 to 7.7%; hpai-e, 0 to 4.3% were characterized by 'northern blotting' and s1 nuclease analysis. they were compared with the mrnas transcribed from the ad5 e1 region in the early and late stages of lytic infection. it is shown that in xhoi-c-transformed cells the same mrnas were transcribed as early during lytic infection: two co-terminal mrnas from region e1a, differin ... | 1983 | 6302209 |
| avian oncovirus mh2: molecular cloning of proviral dna and structural analysis of viral rna and protein. | viral rna, molecularly cloned proviral dna, and virus-specific protein of avian retrovirus mh2 were analyzed. the complexity and sequence conservation of the transformation-specific v-myc sequences of mh2 rna were compared with those of the other members of the mc29 subgroup of acute leukemia viruses, mc29, cmii, and ok10, and with chicken cellular c-myc sequences. all t1 oligonucleotides mapping within the 1.3-kilobase coding region of mc29 v-myc have homologous counterparts in the rnas of all ... | 1983 | 6310159 |
| method for recovery of enteric viruses from estuarine sediments with chaotropic agents. | an evaluation was made of the ability of chaotropes, low-molecular-weight ionic compounds which enhance the solubilization of hydrophobic compounds in water, to improve the recovery of enteric viruses from highly organic estuarine sediments. chaotropic agents alone were poor eluents of polioviruses from sediment but were effective when combined with 3% beef extract. chaotropes of lower potency, nano3, nacl, and kcl, were more efficient eluents than the stronger chaotropes, guanidium hydrochlorid ... | 1983 | 6312884 |
| chemical synthesis and molecular cloning of a stop oligonucleotide encoding an uga translation terminator in all three reading frames. | we have chemically synthesized an oligonucleotide 5'd(tgattgattga)3' 3'd(actaactaact)5' that encodes the translation termination codon tga in all three reading frames. after ligation of appropriate restriction endonuclease linkers to the ends, the double-stranded oligonucleotide (stop-oligonucleotide) was joined to the plasmid pbr322 between the ecori and bamhi, or hindiii and bamhi sites, and the hybrid plasmids were transformed into escherichia coli hb101. four different constructions were obt ... | 1983 | 6313480 |
| construction and testing of mouse--human heteromyelomas for human monoclonal antibody production. | fu-266, a mutant human myeloma cell line sensitive to hypoxanthine/aminopterin/thymidine (hat), was transfected by protoplast fusion with dna of the recombinant plasmid vector psv2-neor, thus acquiring a dominant marker conferring resistance to the antibiotic g-418. one of the resultant neor clones, e-1, was fused to irradiated (500 rads) or unirradiated cells of the hat-sensitive, g-418-sensitive, nonproducer mouse myeloma line x63-ag8.653. hybrid clones were selected in g-418 plus ouabain, thu ... | 1983 | 6316357 |
| characterization of the bovine papilloma virus plasmid maintenance sequences. | bovine papilloma virus (bpv-1) establishes itself as a multicopy nuclear plasmid in somatic mammalian cells in culture. we report here that two discontinuous regions within the viral genome can independently support extrachromosomal replication of the tn5 neomycinr gene in cells that provide viral factors in trans. the viral plasmid maintenance sequences (pms) act in cis and will integrate along with the marker gene in cell lines that do not provide bpv-1 gene products. pms-1 is localized within ... | 1984 | 6319020 |
| heterogeneity of sindbis virus glycoprotein e1 and its modification by host cell transformation. | the electrophoretic properties of glycoprotein e1 of sindbis virus grown in rous sarcoma virus-transformed cells were compared with those of sindbis virus grown in untransformed cells. isoelectric focusing in a gel containing 9.5 m-urea and 2% nonidet p40 indicated that the glycoprotein e1 of sindbis virus from the untransformed cells was electrochemically heterogeneous and consisted of four components, whose isoelectric points (pis) ranged from 6.2 to 6.7; the e1 of sindbis virus from the trans ... | 1984 | 6319579 |
| infection of eucaryotic cells by helper-independent recombinant adenoviruses: early region 1 is not obligatory for integration of viral dna. | recombinant viral genomes carrying a selectable drug resistance marker have been constructed by insertion of a hybrid gene for neomycin resistance into the helper-independent adenovirus vector, delta e1/x. the hybrid gene consists of sequences coding for the aminoglycoside 3'-phosphotransferase ii from tn5, under the control of the simian virus 40 early promoter, and renders mammalian cells resistant to the neomycin analog, g-418. most of adenovirus early region 1 is deleted from delta e1/x (nuc ... | 1984 | 6323759 |
| assembly in vitro of a spanning membrane protein of the endoplasmic reticulum: the e1 glycoprotein of coronavirus mouse hepatitis virus a59. | the e1 glycoprotein of coronavirus mouse hepatitis virus a59 was synthesized in vitro by translation of viral mrna in the presence of dog pancreatic microsomes. its disposition in the membrane was investigated by digestion with proteases and by selective nh2-terminal labeling. the protein spans the membrane, but only small portions from the nh2 and cooh terminus are exposed respectively in the lumenal and cytoplasmic domains; the bulk of the molecule is apparently buried in the membrane. the pro ... | 1984 | 6324191 |
| characterization of barmah forest virus: an alphavirus with some unusual properties. | barmah forest virus has been characterized in a number of ways including electron microscopy of infected cells; physical studies of the virion, its rna, and associated proteins; n-terminal sequence analysis of the two envelope glycoproteins; studies of macromolecular species present in infected cells; and serological cross-reactions with alphaviruses and bunyaviruses. from these results barmah forest virus is clearly an alphavirus since the structure of the virion, the mode of replication, and t ... | 1984 | 6324461 |
| trypsin-treated ma-104: a sensitive cell line for isolating enteric viruses from environmental samples. | during a 1-year survey of enteroviruses in wastewater samples from the lorraine area, three widely used continuous monkey kidney cell lines were tested: bgm, vero, and trypsin-treated ma-104. decontaminated samples from secondary wastewater treatment plants (influent or effluent) were directly inoculated onto cells, and viruses were revealed after two passages with a liquid medium technique. out of the total percentage of positive isolates with the three systems (32.7) 24.7% were found with ma-1 ... | 1984 | 6324675 |
| release of fatty acids from virus glycoproteins by hydroxylamine. | the fatty acids bound to the glycoproteins of sindbis and vesicular stomatitis viruses can be released by treating the protein with 1 m hydroxylamine at ph 8.0, but the rates of release vary greatly among the three proteins. the most labile fatty acyl bonds were in the sindbis virus pe2/e2 proteins and the most stable were in the e1 protein. some of the fatty acids in sindbis virus glycoproteins were reduced to the alcohol after treatment with sodium borohydride, indicating that protein-bound fa ... | 1984 | 6324873 |
| the carbohydrates of mouse hepatitis virus (mhv) a59: structures of the o-glycosidically linked oligosaccharides of glycoprotein e1. | two size classes of o-glycosidically linked oligosaccharides were liberated from glycoprotein e1 of mouse hepatitis virus (mhv) a59 by reductive beta-elimination and separated by h.p.l.c. the structures of the reduced oligosaccharides were determined by successive exoglycosidase digestions and by methylation analyses involving combined capillary gas chromatography-mass spectrometry and mass fragmentography after chemical ionization with ammonia. oligosaccharide a (neu5ac alpha 2----3 gal beta 1- ... | 1984 | 6325180 |
| replication of coronavirus mhv-a59 in sac- cells: determination of the first site of budding of progeny virions. | during infection of sac- cells by murine coronavirus mhv a59 the intracellular sites at which progeny virions bud correlate with the distribution of the viral glycoprotein e1. budding is first detectable by electron microscopy at 6 to 7 hours post infection in small, smooth, perinuclear vesicles and tubules in a region transitional between the rough endoplasmic reticulum and the golgi apparatus. at later times the rough endoplasmic reticulum becomes the major site of budding and accumulation of ... | 1984 | 6325194 |
| determination of cytomegalovirus antibodies by enzyme-linked immunosorbent assay (elisa) in women of fertile period. | such cytomegalovirus antibodies as the igg and igm are investigated in the present work. investigation was carried out on 301 sera of fertile aged women (between 18 to 35 years of age) under the enzyme-linked immunosorbent assay (elisa). only one dilution has been made i.e. 1:40 and the final dilution was worked out from regression graph obtained from a previously titred human positive serum analysis; igg antibodies were found in 265 cases (88%), appearing igm antibodies in 4 of them, with the r ... | 1984 | 6325535 |
| post-translational glycosylation of coronavirus glycoprotein e1: inhibition by monensin. | the intracellular sites of biosynthesis of the structural proteins of murine hepatitis virus a59 have been analyzed using cell fractionation techniques. the nucleocapsid protein n is synthesized on free polysomes, whereas the envelope glycoproteins e1 and e2 are translated on the rough endoplasmic reticulum (rer). glycoprotein e2 present in the rer contains n-glycosidically linked oligosaccharides of the mannose-rich type, supporting the concept that glycosylation of this protein is initiated at ... | 1982 | 6327272 |