| murray valley encephalitis virus infection in mosquitoes and domestic fowls in queensland, 1974. | field studies during an epidemic of murray valley encephalitis (mve) led to the isolation of mve virus from a pool of mosquitoes (culex annulirostris) and a sentinel chicken from charleville, south-west queensland. a high proportion of domestic fowls at charleville had antibody to mve virus at the beginning of february 1974, in advance of the first case recognized in queensland and allowing early warning from health authorities. a survey of antibody in domestic fowls in mid-1974 suggested widesp ... | 1976 | 13773 |
| the proteins of murray valley encephalitis virus. | proteins specified by murray valley encephalitis virus were labelled during virus growth in vero and in ps cells, and separated by polyacrylamide gel electrophoresis. the purified virus particle contains three proteins (v-1, v-2 and v-3) whereas the slow sedimenting haemagglutinin or virus sub-particle lacks the core protein v-2 but contains nv-2, a non-structural protein. seven non-structural proteins in addition to v-2 and v-3 were identified in infected cells. electrophoretic profiles by viru ... | 1975 | 806663 |
| isolation of murray valley encephalitis virus from the brains of three patients with encephalitis. | murray valley encephalitis virus was isolated from the brains of three patients who died from encephalitis during the 1974 epidemic. isolation of the virus from autopsy material was successful when death occurred within two weeks of the onset of illness; however, no isolations were made from specimens collected before death or from autopsy material obtained from patients who died more than two weeks after the onset of symptoms. the virus was recovered most frequently in embryonated eggs, but two ... | 1976 | 994931 |
| serological evidence of inter-epidemic infection of feral pigs in new south wales with murray valley encephalitis virus. | the sera of 617 feral pigs, collected from three widely separated areas of northern and central new south wales, were examined for antibody to murray valley encephalitis (mve) virus and to ross river virus. haemagglutination-inhibition (hi) antibody was detected to mve in 58% of sera and to ross river virus in 15% of sera. neutralization tests suggested that the mve hi antibody resulted from infection with mve virus in the summers of 1971-1972 and 1972-1973 when the virus was not known to be act ... | 1976 | 1016127 |
| isolation of murray valley encephalitis virus from sentinel chickens. | sentinel chickens were established in 3 centres along the murray valley on 20 december 1973. the demonstration of antibody in the serum of chickens in the mildura and kerang areas indicated sindbis virus activity late in december 1973 and early in january 1974. tests for antibody to mve virus were negative until blood collected from one chicken at echuca on 27 february 1974 and several chickens at mildura and kerang on 14 march 1974, showed positive hi reactions. murray valley encephalitis virus ... | 1975 | 1164265 |
| nuclear localization of dengue 2 virus core protein detected with monoclonal antibodies. | anti-dengue 2 virus core protein monoclonal antibodies (mabs) reacted with antigens in the cytoplasm and in, or on, the nucleus of dengue 2 and dengue 4, but not dengue 1, dengue 3, kunjin or murray valley encephalitis virus-infected cells. these mabs also reacted with the core protein from dengue 1, 2 and 4 virions in western blots. the antigens detected by these mabs could not be detected in uninfected or heat-shocked cells, but were first detected in infected cells approximately 32 h post-inf ... | 1992 | 1279106 |
| the murray valley encephalitis virus prm protein confers acid resistance to virus particles and alters the expression of epitopes within the r2 domain of e glycoprotein. | to study the role of the precursor to the membrane protein (prm) in flavivirus maturation, we inhibited the proteolytic processing of the murray valley encephalitis (mve) virus prm to membrane protein in infected cells by adding the acidotropic agent ammonium chloride late in the virus replication cycle. viruses purified from supernatants of ammonium chloride-treated cells contained prm protein and were unable to fuse c6/36 mosquito cells from without. when ammonium chloride was removed from the ... | 1992 | 1280384 |
| proteolytic processing of a murray valley encephalitis virus non-structural polyprotein segment containing the viral proteinase: accumulation of a ns3-4a precursor which requires mature ns3 for efficient processing. | the proteolytic processing of a non-structural polyprotein segment from the cytoplasmic domain of ns2a to the c terminus of ns5 of murray valley encephalitis (mve) virus was examined, when expressed from cdna via a vaccinia virus recombinant, in transiently transfected cos cells, or synthesized by cell-free translation. cleavages mediated by the virus-encoded proteinase domain in ns3 at the junctions of ns2a-2b, ns2b-3 and ns4b-5 were catalysed efficiently. however, the cleavage at the ns3-4a ju ... | 1992 | 1328486 |
| a synthetic peptide to the e glycoprotein of murray valley encephalitis virus defines multiple virus-reactive t- and b-cell epitopes. | synthetic peptides from the envelope glycoprotein sequence of murray valley encephalitis (mve) virus were previously evaluated in various strains of mice for both the induction of antibody and the in vitro proliferation of peptide-primed t-helper (th) cells. mve peptide 6 (amino acids 230 to 251) elicited reciprocal th- and b-cell reactivity with native mve virus after primary inoculation of c57bl/6 mice. in this study, we prepared overlapping subunit peptides of mve peptide 6 and evaluated thei ... | 1992 | 1383567 |
| murray valley encephalitis acquired in western australia. | to report a recent fatal case of encephalitis associated with evidence of murray valley encephalitis virus infection, only the second fatality from this infection in western australia. | 1991 | 1645843 |
| immunoaffinity purification of the ns1 protein of murray valley encephalitis virus: selection of the appropriate ligand and optimal conditions for elution. | a novel approach was used to select the most suitable antiviral monoclonal antibody (mab) and elution conditions for immunoaffinity purification of the ns1 protein of murray valley encephalitis virus (mve). crude ns1 protein was subjected to a variety of chemical conditions produced by common elution buffers, and tested with a panel of ns1-specific mabs by elisa to determine which buffers denatured antigenic epitopes. buffers that caused least structural damage to ns1 epitopes were tested by eli ... | 1991 | 1648569 |
| detection of immobilised murray valley encephalitis virus rna using oligonucleotide probes with varying degrees of mismatch. | the design of oligonucleotides used for hybridisation studies often utilises available sequence information of the type strain of a particular virus. if hybridisation studies, using such oligonucleotides, are carried out with field isolates of the same virus, the problem of base pair mismatches and consequent difficulties in detection may arise. this study examined the effect of base pair mismatches on the hybridisation between membrane-bound murray valley encephalitis virus (mve) rna derived fr ... | 1991 | 1660491 |
| defined epitope blocking with murray valley encephalitis virus and monoclonal antibodies: laboratory and field studies. | in an attempt to develop a specific serological test for murray valley encephalitis (mve) virus antibodies, a panel of mve monoclonal antibodies was utilised in defined-epitope blocking elisa tests. in sera of mice immunised singly and in combinations of mve, alfuy (alf), and kunjin (kun) viruses, blocking patterns usually distinguished mve infections from those of the other flaviviruses. when blocking tests with selected mabs were applied to 468 flavivirus antibody positive sera collected from ... | 1990 | 1700805 |
| sequence of the 3' half of the murray valley encephalitis virus genome and mapping of the nonstructural proteins ns1, ns3, and ns5. | we have determined the nucleotide sequence of the 3'-terminal half of the rna genome of murray valley encephalitis virus (mve) using seven overlapping cdna clones; an estimated 80-90 nucleotides at the extreme 3'-end remain to be sequenced. in conjunction with previous sequence data for the 5' half (16), we can conclude that the mve genome contains a long open reading frame of 10,302 nucleotides that encodes a polyprotein of 3434 residues. comparison of the mve deduced amino acid sequence with t ... | 1990 | 1702914 |
| epitope analysis of the envelope and non-structural glycoproteins of murray valley encephalitis virus. | previous studies have shown that antibodies produced against strategic flavivirus epitopes play an important role in recovery and immunity. definition of the conformation and location of these epitopes and the degree of their conservation among flaviviruses is important to understanding the humoral response to flavivirus infection. in this study we have examined epitopes recognized by 14 monoclonal antibodies (mabs) produced to the envelope (e) and non-structural (ns1) proteins of murray valley ... | 1990 | 1703213 |
| t-helper cell and associated antibody response to synthetic peptides of the e glycoprotein of murray valley encephalitis virus. | a battery of 16 synthetic peptides, selected primarily by computer analysis for predicted b- and t-cell epitopes, was prepared from the deduced amino acid sequence of the envelope (e) glycoprotein of murray valley encephalitis (mve) virus. we examined all of the peptides for t-helper (th)-cell recognition and antibody induction in three strains of mice: c57bl/6, balb/c, and c3h. lymphoproliferative and interleukin-2 assays were performed on splenic t cells from mice inoculated with peptides in f ... | 1991 | 1832722 |
| persistent infection of vero cells by the flavivirus murray valley encephalitis virus. | murray valley encephalitis (mve) virus strain or2 was serially passaged on vero cells to establish a persistent infection which was maintained for over 300 days. supernatants from infected cells protected vero cells from c.p.e. and caused up to a 95% reduction of wild-type virus yield. these protective and interfering effects suggest that defective interfering (di) particles are responsible for the establishment and maintenance of the mve virus persistent infection. the persistently infected cel ... | 1991 | 1848592 |
| anti-mosquito antibodies reduce the susceptibility of aedes aegypti to arbovirus infection. | aedes aegypti (l.) mosquitoes showed a significant reduction in susceptibility to infection with ross river virus and murray valley encephalitis virus when they were fed on a blood-virus mixture containing rabbit antibodies to mosquito midgut components. presence of the antibodies did not demonstrably affect virus titres in infected mosquitoes, nor the transmission of virus from infected mosquitoes to vertebrates. | 1990 | 1966777 |
| the 5'-terminal non-coding region of murray valley encephalitis virus rna is highly conserved. | the 5' non-coding region of the genomes of 11 isolates of murray valley encephalitis virus from australia and papua new guinea were examined by primer extension sequencing. although the 5' non-coding region of all isolates was found to be highly conserved, three isolates were significantly different in that they contained extra uridine residues. two of these isolates from papua new guinea contained an extra uridine residue, nominally positioned after nucleotide 54, which was absent from all but ... | 1990 | 2154536 |
| entry of neurotropic arboviruses into the central nervous system: an in vitro study using mouse brain endothelium. | arbovirus infection of cerebral microvascular endothelial cells was investigated in an in vitro mouse brain endothelial (mbe) cell model. alphaviruses replicated to a greater extent than did flaviviruses, indicating that viremia may be important in neuroinvasion. also, some viruses (e.g., semliki forest virus) replicated to high titers while others (e.g., murray valley encephalitis virus) did not. viruses that replicated to high titers showed luminal polarity of virus release, indicating that in ... | 1990 | 2156944 |
| host cell selection of murray valley encephalitis virus variants altered at an rgd sequence in the envelope protein and in mouse virulence. | we have passaged the prototype strain of murray valley encephalitis virus in sw13 (human) cells, sequenced the e and m genes, and examined the virulence of the passaged virus for 21-day-old mice following intracranial and intraperitoneal inoculation. six independent passage series were carried out: four in the presence of mouse hyperimmune ascitic fluid and two without antibody. changes were observed in the e protein deduced amino acid sequence for each of the six 10th passage stocks sequenced. ... | 1990 | 2161151 |
| studies on the glycosylation of flavivirus e proteins and the role of carbohydrate in antigenic structure. | the glycosylation pattern of several flavivirus e proteins as well as the role of carbohydrate in biological functions and the antigenic structure of tick-borne encephalitis (tbe) virus were investigated by the use of specific endoglycosidases. endoglycosidase f digestion revealed the presence of a single asparagine-linked oligosaccharide side chain in tbe virus (western and far eastern subtype), louping iii virus, murray valley encephalitis virus, and rocio virus. consistent with published sequ ... | 1987 | 2441520 |
| type-specific monoclonal antibodies produced to proteins of murray valley encephalitis virus. | two monoclonal antibodies have been produced to the flavivirus, murray valley encephalitis (mve). immunofluorescent antibody and elisa tests revealed that one antibody was specific for mve while the other cross-reacted weakly with alfuy and kunjin viruses. these antibodies have neither haemagglutination inhibition nor neutralising activity. one of the monoclonal antibodies reacted with the envelope glycoprotein (e) and a 45,000 mw protein, while the other reacted with a protein of 23,000 daltons ... | 1988 | 2453454 |
| antigenic structure of the murray valley encephalitis virus e glycoprotein. | to complement our battery of st louis encephalitis (sle) virus monoclonal antibodies (mabs), we isolated and characterized mabs reactive with another member of the sle virus serocomplex, murray valley encephalitis (mve) virus. from 40 fusion products, we isolated 10 stable hybridomas. the combination of sle and mve virus mabs defined eight epitopes on the mve envelope (e) glycoprotein. six of these epitopes (e-1a, e-1c, e-1d, e-3, e-4a, e-4b) were identical to those previously demonstrated on sl ... | 1988 | 2453607 |
| synthetic peptides derived from the deduced amino acid sequence of the e-glycoprotein of murray valley encephalitis virus elicit antiviral antibody. | we used computer analysis to study hydrophilicity, homology, surface accessibility, molecular flexibility, and secondary structure of the deduced amino acid sequence of the flavivirus envelope (e)-glycoprotein. using the results, we modified the e-glycoprotein antigenic structure proposed by nowak and wengler (1987, virology, 156, 127-137). our model predicts considerable overlaps in the previously defined domains. we have prepared 11 synthetic peptides from the deduced amino acid sequence of th ... | 1989 | 2472704 |
| isolation of murray valley encephalitis and ross river viruses from aedes normanensis (diptera: culicidae) in western australia. | of eight viruses isolated from 28,909 female (643 pools) aedes normanensis collected from the north of western australia, two were identified as murray valley encephalitis virus and six as ross river virus. the two isolates of murray valley encephalitis virus represent the first confirmed isolations of this virus from an aedes species. the possible implications of these findings with regard to virus survival mechanisms during the dry season are discussed. | 1989 | 2540334 |
| kunjin virus isolates of australia are genetically homogeneous. | the genomes of 22 isolates of kunjin virus (kun) from australia were characterized and compared using rnase t1 oligonucleotide fingerprinting. the results show that all isolates belonged to one topotype, the distribution of which covered the entire australian continent. this finding is similar to that of murray valley encephalitis virus, but in contrast to the results reported for some other flaviviruses such as saint louis encephalitis virus. | 1989 | 2552010 |
| larval diet and the vector competence of culex annulirostris (diptera: culicidae) for murray valley encephalitis virus. | culex annulirostris skuse larvae were reared on two different amounts of powdered dog chow and yeast, low intake (2.8 micrograms/larva) and high intake (8.4 micrograms/larva), to produce adults with mean wing lengths of 3.25 and 3.7 mm, respectively. the resulting adults were fed different dosages of murray valley encephalitis virus and after 10 d extrinsic incubation at 28 degrees c, the infection rate, transmission rate, salivary gland, and body titers were determined. there were no significan ... | 1989 | 2552121 |
| the vector competence of culex annulirostris, aedes sagax and aedes alboannulatus for murray valley encephalitis virus at different temperatures. | culex annulirostris skuse, colonized from brisbane, queensland, and mildura, victoria, australia, were effective vectors of murray valley encephalitis virus at 20, 27 and 32-35 degrees c with full extrinsic incubation periods of 15, 10 and 4 days respectively. at 20 degrees c, 7-11 days post-infection, transmission by the mildura colony (0-20%) was less efficient than the brisbane colony (30-70%) but both were capable of 75-100% transmission after longer extrinsic incubation periods. discriminan ... | 1989 | 2562418 |
| rearing temperature influences flavivirus vector competence of mosquitoes. | culex annulirostris skuse mosquitoes (brisbane strain) were reared at 20 degrees c or 27 degrees c and the adult females were experimentally infected by feeding murray valley encephalitis virus (mve). they were then maintained (a) in the insectary at 20 degrees c, after rearing at either 20 degrees c or 27 degrees c; (b) at ambient outdoor temperatures, range 12.2-28.9 degrees c, mean 19.6 degrees c; or (c) at 27 degrees c after rearing at 27 degrees c. there was no significant difference in rat ... | 1989 | 2562419 |
| nucleotide and complete amino acid sequences of kunjin virus: definitive gene order and characteristics of the virus-specified proteins. | a kunjin (kun) virus cdna sequence of 10664 nucleotides was obtained and it encoded a single open reading frame for 3433 amino acids. partial n-terminal amino acid analyses of kun virus-specified proteins identified the polyprotein cleavage sites and the definitive gene order. the gene order relative to that proposed for yellow fever (yf) virus is as follows: kun 5'-c.gp20.e.gp44.p19.p10.p71.(?).p21.p98-3' yf 5'-c.prm.e.ns1.ns2a.ns2b.ns3.ns4a.ns4b. ns5-3'. the order of putative signal sequences ... | 1988 | 2826659 |
| conserved elements in the 3' untranslated region of flavivirus rnas and potential cyclization sequences. | we have isolated a cdna clone after reverse transcription of the genomic rna of asibi yellow fever virus whose structure suggests it was formed by self-priming from a 3'-terminal hairpin of 87 nucleotides in the genomic rna. we have also isolated a clone from cdna made to murray valley encephalitis virus rna that also appears to have arisen by self-priming from a 3'-terminal structure very similar or identical to that of yellow fever. in addition, 3'-terminal sequencing of the s1 strain of dengu ... | 1987 | 2828633 |
| sequence and secondary structure analysis of the 5'-terminal region of flavivirus genome rna. | the 5'-terminal noncoding region sequences were determined for the genome rnas of seven strains of st. louis encephalitis virus (slev) and one strain of west nile virus (wnv) using a single synthetic cdna primer complementary to the 5'-terminus of the coding region of a strain of wnv rna. the 5'-terminal sequences obtained for the slev and wnv rnas were compared with published sequences for yellow fever virus (yfv), murray valley encephalitis virus (mvev), and dengue virus. while only short regi ... | 1988 | 2829420 |
| murray valley encephalitis virus field strains from australia and papua new guinea: studies on the sequence of the major envelope protein gene and virulence for mice. | we have compared the nucleotide sequence of the gene encoding the major envelope (e) protein of a number of murray valley encephalitis virus (mve) isolates from australia and papua new guinea (png). the isolates, from widely separated geographic regions, were from four fatal human cases, a heron, and six mosquito pools and covered a period of 25 years. the sequences of the australian strains were notable for their similarity, showing not more than 1.7% nucleotide sequence divergence in pairwise ... | 1988 | 2838962 |
| genetic variation of murray valley encephalitis virus. | the genomes of 21 isolates of murray valley encephalitis virus (mve) from australia and papua new guinea were characterized and compared using rnase t1 oligonucleotide fingerprinting. most australian isolates grouped in clusters that were linked with a similarity coefficient of greater than 75%, indicating substantial homogeneity. two isolates grouped as a cluster that linked with other isolates at a level of 67%. these two isolates, one from the north and one from the south-east of australia we ... | 1988 | 2841405 |
| genetic differentiation of murray valley encephalitis virus in australia and papua new guinea. | the genetic relatedness of ten murray valley encephalitis virus (mve) isolates from australia has been examined by comparing haeiii and taqi restriction digest profiles of cdna to virion rna. the isolates were from the murray valley region of south-eastern australia and from the ord river region of western australia and spanned a period of 23 years (1951-1974). the isolates generated closely similar restriction digest profiles. the extent of similarity suggested that the level of nucleotide sequ ... | 1986 | 2884985 |
| experimental infection with murray valley encephalitis virus. pigs, cattle, sheep, dogs, rabbits, macropods and chickens. | a total of 142 young animals including 10 domestic and 14 feral pigs, 12 hereford calves, 12 crossbred and 24 merino lambs, 11 dogs, 8 domestic and 16 feral rabbits, 14 grey kangaroos, 9 agile wallabies and 12 chickens was exposed to infection with 4 strains of murray valley encephalitis virus (mve), mainly using orally infected culex annulirostris mosquitoes. in terms of their viraemic response, the animals were grouped into high (grey kangaroos, rabbits), moderate (pigs, dogs, chickens) and lo ... | 1985 | 2990398 |
| experimental infection with murray valley encephalitis virus: galahs, sulphur-crested cockatoos, corellas, black ducks and wild mice. | orally infected culex annulirostris or intravenous injections were used to infect 10 galahs, 15 sulphur-crested cockatoos, 12 corellas, 4 black ducks and 10 wild mice with murray valley encephalitis (mve) virus. the birds produced moderate viraemias of titres of log 10(2.0)-10(6.0) suckling mouse intracerebral (smic) ld50/ml for durations of 1-9 d. however, the wild mice developed low grade viraemia for 1-4 d. recipient cx annulirostris feeding on viraemic birds sustained infection rates of 0-10 ... | 1985 | 3004402 |
| partial nucleotide sequence of the murray valley encephalitis virus genome. comparison of the encoded polypeptides with yellow fever virus structural and non-structural proteins. | the sequence of 5400 bases corresponding to the 5'-terminal half of the murray valley encephalitis virus genome has been determined. the genome contains a 5' non-coding region of about 97 nucleotides, followed by a single continuous open reading frame that encodes the structural proteins followed by the non-structural proteins. amino acid sequence homology between the murray valley encephalitis and yellow fever (rice et al., 1985) polyproteins is 42% over the region sequenced. the start points o ... | 1986 | 3009829 |
| arbovirus infection in a murray valley community. | serum antibodies to ross river virus and murray valley encephalitis virus were measured during 1974-1975 in residents of echuca, an urban murray valley community. a representative group of volunteers was obtained by random selection of households. the prevalence of antibodies to both viruses increased progressively with age. prevalence was equal in both sexes for both viruses in all age groups, indicating that the risk of infection was mainly determined by geography rather than by personal activ ... | 1986 | 3010928 |
| cloning full-length dengue type 4 viral dna sequences: analysis of genes coding for structural proteins. | dna sequences (approximately 11,000 nucleotides) representing the full-length genome of the dengue virus type 4 were cloned. the sequence of the first 2,429 nucleotides at the 5' terminus which includes the coding region for the structural proteins is presented. the virion structural proteins are encoded in one long open reading frame specifying a polyprotein precursor which is apparently proteolytically cleaved by a mechanism resembling that proposed for expression of structural proteins of oth ... | 1986 | 3022479 |
| a mathematical model for the rural amplification of murray valley encephalitis virus in southern australia. | the exacerbation of epidemics of murray valley encephalitis in southern australia during 1951 and 1974 was studied retrospectively to determine when viral introduction may have occurred. data from studies spanning over 30 years were utilized 1) to determine the number of infective culex annulirostris necessary to cause one clinical case, based on known host-feeding patterns and the subclinical infection rate in man, and 2), using mathematical modeling, to calculate the likely duration of the rur ... | 1987 | 3826047 |
| letter: murray valley encephalitis virus in eastern australia, 1971. | | 1973 | 4758166 |
| proteins of the group b arbovirus kunjin. | purified kunjin virus was disrupted with sodium dodecyl sulfate, urea, and mercaptoethanol or acetic acid. electrophoresis on 7.5% polyacrylamide gel separated four proteins of high (120,000), intermediate (65,000) and low (18,000 and 13,000) molecular weights. a "core" particle was obtained by degradation of the virion with deoxycholate at 0 c; it contained the viral ribonucleic acid and the two small structural proteins. the "envelope" material released from around the core was identified with ... | 1969 | 4982830 |
| the immune response to viruses in calves. i. response to murray valley encephalitis virus. | | 1968 | 5245225 |
| immunotyping of different strains of japanese encephalitis virus by antibody-absorption, haemagglutination-inhibition and complement-fixation tests. | the immunological characteristics of 26 strains of japanese encephalitis virus (jev) isolated in japan and malaya between 1935 and 1966 have been investigated mainly by the antibody-absorption variant of the haemagglutination-inhibition test, and to a certain extent also by conventional haemagglutination-inhibition and complement-fixation tests. the antibody-absorption technique shows promise as a routine method for the immunotyping of jev.at present, two immunotypes can be distinguished. one co ... | 1968 | 5302450 |
| allantoic fluid as a source of arbovirus hemagglutinin. | noninfectious hemagglutinins were prepared from the allantoic fluids of embryonated chicken eggs infected with sindbis virus or with murray valley encephalitis virus. | 1970 | 5466134 |
| propagation of sindbis virus, murray valley encephalitis virus and getah virus. | | 1969 | 5779036 |
| [arboviral diseases in south-west pacific islands (author's transl)]. | islands of the south-west pacific area belong to the melanesian group, excepted niue, tonga, wallis and futuna which are polynesian. through new guinea, there is a geographic relation to the eastern part of australia, rich of 42 arbovirus types. dengue and ross river fever are the most important arboviral diseases in the region; both affect islanders after introduction of virus by travellers to localities where efficient vectors are present. dengue types 1, 2 and 4 were isolated from man and fro ... | 1981 | 6116150 |
| isolation of murray valley encephalitis virus and other arboviruses in the ord river valley 1972-1976. | this paper summarizes the isolation of arboviruses from mosquitoes collected in the ord valley between 1972 and 1976. a total of one hundred and ninety five strains of at least fifteen antigenically distinct viruses have been isolated. seven of these isolates appear to be "new' antigenic types, and several are undergoing further testing. these are three new rhabdoviruses (kununurra [or194], a virus provisionally named kimberley [or250] and or189 [provisionally named parry's creek]), three ungrou ... | 1981 | 6117274 |
| effect on mice of infection during pregnancy with three australian arboviruses. | infection of pregnant mice with ross river or getah viruses after the establishment of a functional placenta resulted in fetal infection with these viruses. however, only with ross river virus was there any significant fetal death. there was significant post-partum mortality in mice infected in utero with ross river but not with getah virus. in contrast, significant post-partum mortality occurred in murray valley encephalitis virus-infected mice despite the inability of the virus to cross the pl ... | 1981 | 6259957 |
| transovarial transmission of murray valley encephalitis virus by aedes aegypti (l). | in laboratory studies, murray valley encephalitis virus was transmitted transovarially by orally infected aedes aegypti to approximately 1.5% of both adult male and female progeny. | 1980 | 6263238 |
| envelope protein of the flavivirus kunjin is apparently not glycosylated. | the envelope protein e (formerly designated v3) of the flavivirus kunjin was not labelled with radioactive galactose, mannose or glucosamine during virus growth in vero cells. on electrophoresis through polyacrylamide gels containing sds, the envelope (e) protein migrated more rapidly than related intracellular virus-specified glycoproteins. furthermore, e had a density in cscl solution consistent with that of a protein lacking carbohydrate, and did not bind to concanavalin a-agarose. in contras ... | 1982 | 6279774 |
| molecular epidemiology of tick-borne encephalitis virus: peptide mapping of large non-structural proteins of european isolates and comparison with other flaviviruses. | nine virus-specified proteins were identified by sds-polyacrylamide gel electrophoresis in [35s]methionine-labelled chick embryo cells infected with tick-borne encephalitis (tbe) virus by comparison with mock-infected cells. these proteins were designated p91, p74, p72, p67, gp53(e), p47, p25, p15(c) and p14.5 according to their molecular weights. peptide mapping of p91, p67, gp53(e) and p47 from tbe virus-infected cells, as well as those of the corresponding proteins from west nile virus (wnv)- ... | 1982 | 6292351 |
| variation in arbovirus infection rates in species of birds sampled in a serological survey during an encephalitis epidemic in the murray valley of south-eastern australia, february 1974. | there was extensive and exuberant breeding of waterbirds before and during an epidemic of arboviral encephalitis in the murray valley of south eastern australia in 1974. as estimated by haemagglutination inhibition tests on 432 bird sera collected between 4th and 13th february, 1974, infection with murray valley encephalitis virus, kunjin virus and possibly other flaviviruses was concentrated in species of the order ciconiiformes (55% positive) and pelecaniformes (41%), compared with only 5% in ... | 1982 | 6299259 |
| primary viraemia responses of herons to experimental infection with murray valley encephalitis, kunjin and japanese encephalitis viruses. | rufous night herons, pacific herons, little egrets and intermediate egrets were experimentally infected with murray valley encephalitis, kunjin or japanese encephalitis viruses. viraemias of at least one day's duration were detected in all birds except two intermediate egrets inoculated with a very low dose of kunjin virus and one rufous night heron inoculated with japanese encephalitis virus. there was usually a viraemia of 3 to 5 days' duration commencing on the first or second day and continu ... | 1983 | 6326724 |
| role of antibodies and host cells in plaque enhancement of murray valley encephalitis virus. | chicken antisera to murray valley encephalitis (mve) virus, when incubated with virus and assayed for plaques on chicken embryo (ce) monolayers, neutralized mve virus at high concentrations of antibody, but caused increases in plaque counts at low concentrations of antibody. plaque enhancement did not occur when the same virus-antibody mixtures were assayed on a continuous line of rhesus monkey kidney cells (llc-mk2), nor when the anti-mve antibody was of mammalian origin and the assay system wa ... | 1983 | 6842678 |
| t-helper cell epitopes on the e-glycoprotein of dengue 2 jamaica virus. | to identify t-helper (th)-cell epitopes, we analyzed 25 synthetic peptides, which included most of the 495-amino-acid sequence of the envelope (e)-glycoprotein of dengue 2 virus. the peptides were analyzed in three mouse strains, balb/c (h-2d), c57bl/6 (h-2b), and outbred nih-swiss, for their ability to elicit antibody or prime the th-cell compartment following two inoculations in freund's incomplete adjuvant. sixteen peptides were able to elicit an antipeptide antibody response in one or more m ... | 1994 | 7505071 |
| the flavivirus nonstructural protein ns3 is a dominant source of cytotoxic t cell peptide determinants. | vaccinia virus recombinants encoding regions of the murray valley encephalitis virus (mve) genome, which together cover the entire viral coding region, were employed to identify the mve protein which is the dominant source of cd8+, cytotoxic, t cell antigenic determinant(s) presented by the mouse h-2kk major histocompatibility antigen. mve and west nile virus-immune, h-2k-restricted, effector cells recognized peptides derived from the mve nonstructural polyprotein segment, and in this region the ... | 1994 | 7516597 |
| two possible mechanisms for survival and initiation of murray valley encephalitis virus activity in the kimberley region of western australia. | two possible mechanisms are described for the initiation of murray valley encephalitis (mve) virus activity in arid, epizootic regions of tropical australia. virus isolations were made from mosquitoes trapped shortly after the first heavy wet season rains and flooding in the east kimberley, which followed approximately nine months of drought. a number of isolates of mve virus were obtained, including isolates from pools of blood-engorged culex annulirostris mosquitoes and from a single pool of m ... | 1995 | 7625542 |
| murray valley encephalitis virus envelope protein antigenic variants with altered hemagglutination properties and reduced neuroinvasiveness in mice. | neutralization escape variants of murray valley encephalitis virus were selected using a type-specific, neutralizing, and passively protective anti-envelope protein (e) monoclonal antibody (4b6c-2) which defines epitope e-1c. nucleotide sequence analysis revealed single nucleotide changes in the e genes of 15 variants resulting in nonconservative amino acid substitutions in all cases. one variant had a three-nucleotide deletion in the e gene which resulted in loss of serine at residue 277. chang ... | 1995 | 7645203 |
| a novel complex formed between the flavivirus e and ns1 proteins: analysis of its structure and function. | we examined the structural features and functional significance of a novel complex which forms between the envelope (e) protein and nonstructural protein ns1 of murray valley encephalitis (mve) virus. western blot analysis of virus-infected c6/36 cell lysates revealed that the undenatured form of this e-ns1 complex was a heat-sensitive e-(ns1 dimer) complex. furthermore, the e-ns1 complex was observed in cells infected with kunjin, japanese encephalitis, west-nile and kokobera viruses which indi ... | 1995 | 7646339 |
| immunodominant epitopes on the ns1 protein of mve and kun viruses serve as targets for a blocking elisa to detect virus-specific antibodies in sentinel animal serum. | two mosquito-borne flaviviruses, murray valley encephalitis (mve) and kunjin (kun), are the aetiological agents of australian encephalitis. mve causes a severe and potentially fatal form of the disease while kun is responsible for only a few relatively mild cases. therefore it is important that serological tests used in flavivirus surveillance differentiate between infections with these two viruses. however, this has been hampered in the past by the close antigenic relationships between flavivir ... | 1995 | 7738140 |
| el niño-southern oscillation and vector-borne disease. | | 1993 | 7901589 |
| generation of long flavivirus expression cassettes by in vivo recombination and transient dominant selection. | assembly of expression cassettes coding for large segments of viral polyproteins is often complicated or impossible due to the instability of the resulting recombinant (re-) plasmids during propagation in escherichia coli. using the transient dominant selection approach described for the construction of vaccinia virus recombinants (re-vv), we have constructed several intermediate vectors and developed a procedure which enables direct assembly of long expression cassettes in the vv genome by in v ... | 1994 | 7958993 |
| genetic studies of flavivirus resistance in inbred strains derived from wild mice: evidence for a new resistance allele at the flavivirus resistance locus (flv). | studies of genetic resistance to flavivirus infection in laboratory mice have led to the development of a single model in which resistance is conferred by an autosomal dominant gene designated flvr. because of evidence suggesting that wild mice carry virus resistance genes which are not present in laboratory mice, we compared flavivirus resistance in the inbred strains casa/rk, cast/ei, and mold/rk, which are derived directly from wild mice, and the congenic strains c3h/rv (flvr/flvr) and c3h/he ... | 1993 | 8380081 |
| flavivirus premembrane protein cleavage and spike heterodimer secretion require the function of the viral proteinase ns3. | flavivirus protein biosynthesis involves the proteolytic processing of a single polyprotein precursor by host- and virus-encoded proteinases. in this study, the requirement for the proteolytic function of the viral proteinase ns3 for correct processing of a polyprotein segment encompassing the murray valley encephalitis virus structural proteins is shown. the ns3-mediated cleavage in the structural polyprotein region presumably releases the capsid protein from its membrane anchor and triggers th ... | 1993 | 8392191 |
| australian x disease, murray valley encephalitis and the french connection. | epidemics of a severe encephalitis occurred in eastern australia between 1917 and 1925, in which over 280 cases were reported with a fatality rate of 68%. the disease had not been described previously and was called australian x disease. the next epidemic occurred in south-east australia in the summer of 1950-51. the disease was given its name of murray valley encephalitis as this was the area from which most cases were reported. a virus was isolated by eric french in victoria, and about the sam ... | 1995 | 8545982 |
| a comparison of the spread of murray valley encephalitis viruses of high or low neuroinvasiveness in the tissues of swiss mice after peripheral inoculation. | a murray valley encephalitis virus (mve) field isolate of high neuroinvasiveness (bh3479) and a neutralization escape variant of low neuroinvasiveness (bhv1) selected from bh3479 (which differ by a single amino acid at residue 277 in the envelope glycoprotein) were examined for their distribution in the tissues of weanling swiss mice at various times after footpad inoculation. bh3479 was first detected in lymph nodes draining the inoculated limb at 24 hr postinoculation (pi) and was found in ser ... | 1996 | 8661392 |
| protective immune responses to the e and ns1 proteins of murray valley encephalitis virus in hybrids of flavivirus-resistant mice. | the lack of an effective animal model has been a major obstacle in attempts to define the role of humoral and cellular immune responses in protection against flavivirus infection. we have used f1 hybrid mice (balb/c x c3h/rv) that are heterozygous for the flavivirus resistance allele f1vr and show reduced virus replication in the brain after intracerebral inoculation. f1 hybrid mice challenged by intracerebral inoculation with murray valley encephalitis (mve) virus developed encephalitis 2-3 day ... | 1996 | 8683218 |
| a mouse-attenuated envelope protein variant of murray valley encephalitis virus with altered fusion activity. | a neutralization escape variant of murray valley encephalitis virus (mve), of low neuroinvasiveness in mice and with low haemagglutination activity, had a reduced rate of replication in cultured cells during the early phase of infection compared to wild-type mve. the variant was internalized by vero cells at a similar rate to wild-type mve at ph 7.4, but had reduced ph-dependent membrane fusion activity. in fusion-from-within experiments in infected mosquito (c6/36) cells, the variant had a lowe ... | 1996 | 8811007 |
| molecular characterization of virus-specific rna produced in the brains of flavivirus-susceptible and -resistant mice after challenge with murray valley encephalitis virus. | natural resistance to flaviviruses in mice is controlled by a single genetic locus, fiv, on chromosome 5. although the mechanism of this resistance is not fully understood, it is believed to operate at the level of virus replication rather than the immune response. it has been hypothesized that enhanced production of viral defective interfering (di) particles is responsible for a substantial reduction in the titres of infectious virus in resistant mice. however, this has never been established a ... | 1997 | 9010281 |
| neurovirulence and neuroinvasiveness of murray valley encephalitis virus mutants selected by passage in a monkey kidney cell line. | variants of the prototype murray valley encephalitis virus (mve-1-51) were selected by serial plaque purification and amplification in monkey kidney (vero) cells. four clones (c1-c4) at passage levels two and nine (p2 and p9) were examined in 21-day-old swiss outbred mice for neuroinvasiveness (assessed from ld50 values after intraperitoneal inoculation) and neurovirulence (ld50 values after intracranial inoculation). the growth characteristics of the clones were determined in intracranially ino ... | 1995 | 9049332 |
| immune response to a murray valley encephalitis virus epitope expressed in the flagellin of an attenuated strain of salmonella. | recent developments in vaccine construction include the use of attenuated, avirulent strains of salmonella as carriers of foreign antigens. these recombinant strains can elicit a heterologous immune response when injected into animals, demonstrating potential for their use in the construction of many vaccines. in the present study, a b-cell epitope of murray valley encephalitis virus (mve) was identified and expressed in a salmonella strain to evaluate its potential to induce a specific immune r ... | 1997 | 9060872 |
| communicable diseases surveillance. | | 1997 | 9140103 |
| the immune response to a b-cell epitope delivered by salmonella is enhanced by prior immunological experience. | attenuated, heterologous strains of salmonella have shown potential as live, recombinant vaccines against foreign pathogens. studies in animal models have demonstrated that immunization with these heterologous vaccines is an effective way to induce both cellular and humoral immune responses against salmonella and the foreign antigen. we studied the consequence of priming mice with salmonella dublin 3-6 months before intraperitoneal administration with the same strain carrying a model b-cell epit ... | 1997 | 9364676 |
| mutagenesis of the ns3 protease of dengue virus type 2. | the flavivirus protease is composed of two viral proteins, ns2b and ns3. the amino-terminal portion of ns3 contains sequence and structural motifs characteristic of bacterial and cellular trypsin-like proteases. we have undertaken a mutational analysis of the region of ns3 which contains the catalytic serine, five putative substrate binding residues, and several residues that are highly conserved among flavivirus proteases and among all serine proteases. in all, 46 single-amino-acid substitution ... | 1998 | 9420267 |
| apoptosis in the mouse central nervous system in response to infection with mouse-neurovirulent dengue viruses. | apoptosis has been suggested as a mechanism by which dengue (den) virus infection may cause neuronal cell death (p. desprès, m. flamand, p.-e. ceccaldi, and v. deubel, j. virol. 70:4090-4096, 1996). in this study, we investigated whether apoptotic cell death occurred in the central nervous system (cns) of neonatal mice inoculated intracerebrally with den virus. we showed that serial passage of a wild-type human isolate of den virus in mouse brains selected highly neurovirulent variants which rep ... | 1998 | 9420294 |
| signal peptidase cleavage at the flavivirus c-prm junction: dependence on the viral ns2b-3 protease for efficient processing requires determinants in c, the signal peptide, and prm. | signal peptidase cleavage at the c-prm junction in the flavivirus structural polyprotein is inefficient in the absence of the cytoplasmic viral protease, which catalyzes cleavage at the cooh terminus of the c protein. the signal peptidase cleavage occurs efficiently in circumstances where the c protein is deleted or if the viral protease complex is present. in this study, we used cdna of murray valley encephalitis virus (mve) to examine features of the structural polyprotein which allow this reg ... | 1998 | 9499070 |
| characterization of defective viral rna produced during persistent infection of vero cells with murray valley encephalitis virus. | defective interfering viral particles are readily produced in cell culture after a high multiplicity of infection with many animal rna viruses. due to defects that they carry in their genomes, their life cycle needs to be complemented by the helper functions provided by a parental virus which makes them both dependent on and competitive with the parental virus. in many instances, this may cause the abrogation of a lytic cycle of the parental virus, leading to a persistent infection. in this pape ... | 1998 | 9499109 |
| genetically determined resistance to flavivirus infection in wild mus musculus domesticus and other taxonomic groups in the genus mus. | inherited resistance to flaviviruses in laboratory mice is a rare trait conferred by an autosomal dominant gene (flvr). to provide information on genetic resistance to flaviviruses in wild mice, we analysed (i) wild m. m. domesticus trapped in australia, and (ii) mice representing other species and subspecies in the genus mus. mice were screened for resistance relative to c3h/hej mice by intracerebral challenge with murray valley encephalitis virus or yellow fever virus, and breeding studies wer ... | 1998 | 9638142 |
| a presumptive case of fatal murray valley encephalitis acquired in alice springs. | a presumptive case of murray valley encephalitis (mve) acquired in alice springs in march 1997 is reported. the patient subsequently died in mackay. the diagnosis of murray valley encephalitis was supported by the detection of flavivirus igm in cerebrospinal fluid. low titres of igm specific to murray valley encephalitis and alfuy were detected in a single serum sample. the patient's travel movements indicate that his infection was acquired in the alice springs vicinity. this conclusion was furt ... | 1998 | 9648367 |
| dna-based and alphavirus-vectored immunisation with prm and e proteins elicits long-lived and protective immunity against the flavivirus, murray valley encephalitis virus. | the immunogenicity and protective efficacy of dna-based vaccination with plasmids encoding the membrane proteins prm and e of the flavivirus murray valley encephalitis virus (mve) were investigated. gene gun-mediated intradermal delivery of dna encoding the prm and e proteins elicited long-lived, virus-neutralising antibody responses in three inbred strains of mice and provided protection from challenge with a high titer inoculum of mve. intramuscular dna vaccination by needle injection also ind ... | 1998 | 9770429 |
| antiapoptotic but not antiviral function of human bcl-2 assists establishment of japanese encephalitis virus persistence in cultured cells. | upon infection of japanese encephalitis virus (jev), baby hamster kidney (bhk-21) and chinese hamster ovary (cho) cells were killed by a mechanism involved in apoptosis. while readily established in a variety of cell lines, jev persistence has never been successfully instituted in bhk-21 and cho cells. since stable expression of human bcl-2 in bhk-21 cells has been shown to delay jev-induced apoptosis, in this study we investigated whether jev persistence could be established in such cells. when ... | 1998 | 9811720 |
| analysis of murine cd8(+) t-cell clones specific for the dengue virus ns3 protein: flavivirus cross-reactivity and influence of infecting serotype. | serotype-cross-reactive dengue virus-specific cytotoxic t lymphocytes (ctl) induced during a primary dengue virus infection are thought to play a role in the immunopathogenesis of dengue hemorrhagic fever (dhf) during a secondary dengue virus infection. although there is no animal model of dhf, we previously reported that murine dengue virus-specific ctl responses are qualitatively similar to human dengue virus-specific ctl responses. we used balb/c mice to study the specificity of the ctl respo ... | 1999 | 9847344 |
| rapid clearance of simian immunodeficiency virus particles from plasma of rhesus macaques. | perturbation of the equilibrium between human immunodeficiency virus type 1 (hiv-1) and the infected host by administering antiretroviral agents has revealed the rapid turnover of both viral particles and productively infected cells. in this study, we used the infusion of simian immunodeficiency virus (siv) particles into rhesus macaques to obtain a more accurate estimate of viral clearance in vivo. consistently, exogenously infused virions were cleared from plasma with an extremely short half-l ... | 1999 | 9847402 |
| australian encephalitis in the northern territory: clinical and epidemiological features, 1987-1996. | the last epidemic of australian encephalitis occurred in 1974. since then, cases have been reported from the kimberley of western australia (wa). | 1998 | 9847946 |
| prm- and cell-binding domains of the dengue virus e protein. | the e-prm proteins of flaviviruses are unusual complexes which play important roles in virus assembly and fusion modulation and in potential immunity-inducing vaccines. despite their importance, little is known about the biogenesis and structural organization of e-prm complexes. pulse-chase radiolabeling of dengue virus-infected vero cells demonstrated a rapid interassociation of e and prm proteins, and sucrose gradient sedimentation analysis suggested that e-prm complexes progressed from simple ... | 1999 | 9971841 |
| identification and analysis of truncated and elongated species of the flavivirus ns1 protein. | the flavivirus non-structural glycoprotein ns1 is often detected in western blots as a heterogeneous cluster of bands due to glycosylation variations, precursor-product relationships and/or alternative cleavage sites in the viral polyprotein. in this study, we determined the basis of structural heterogeneity of the ns1 protein of murray valley encephalitis virus (mve) by glycosylation analysis, pulse-chase experiments and terminal amino acid sequencing. inhibition of n-linked glycosylation by tu ... | 1999 | 10225275 |
| genetic interaction of flavivirus nonstructural proteins ns1 and ns4a as a determinant of replicase function. | nonstructural protein 1 (ns1) of yellow fever virus (yf) is a glycoprotein localized to extracytoplasmic compartments within infected cells. we have previously shown that ns1 can be supplied in trans and is required for viral rna replication, a process thought to occur in membrane-bound cytoplasmic complexes. here we report that the ns1 gene from a related virus, dengue virus (den), is unable to function in the process of yf rna replication. this virus-specific incompatibility leads to a lack of ... | 1999 | 10233920 |
| dengue virus structural differences that correlate with pathogenesis. | the understanding of dengue virus pathogenesis has been hampered by the lack of in vitro and in vivo models of disease. the study of viral factors involved in the production of severe dengue, dengue hemorrhagic fever (dhf), versus the more common dengue fever (df), have been limited to indirect clinical and epidemiologic associations. in an effort to identify viral determinants of dhf, we have developed a method for comparing dengue type 2 genomes (reverse transcriptase pcr in six fragments) dir ... | 1999 | 10233934 |
| mapping of functional elements in the stem-anchor region of tick-borne encephalitis virus envelope protein e. | envelope protein e of the flavivirus tick-borne encephalitis virus mediates membrane fusion, and the structure of the n-terminal 80% of this 496-amino-acid-long protein has been shown to differ significantly from that of other viral fusion proteins. the structure of the carboxy-terminal 20%, the stem-anchor region, is not known. it contains sequences that are important for membrane anchoring, interactions with prm (the precursor of membrane protein m) during virion assembly, and low-ph-induced s ... | 1999 | 10364309 |
| characterization of hepatitis c virus e2 glycoprotein interaction with a putative cellular receptor, cd81. | a truncated soluble form of the hepatitis c virus e2 glycoprotein, e2661, binds specifically to the surface of cells expressing human cd81 (hcd81) but not other members of the tetraspanin family (cd9, cd63, and cd151). no differences were noted between the level of e2661 binding to hcd81 expressed on the surface of rat rbl or km3 cells compared to daudi and molt-4 cells, suggesting that additional human-cell-specific factors are not required for the primary interaction of e2 with the cell surfac ... | 1999 | 10400713 |
| functional analysis of cell surface-expressed hepatitis c virus e2 glycoprotein. | hepatitis c virus (hcv) glycoproteins e1 and e2, when expressed in eukaryotic cells, are retained in the endoplasmic reticulum (er). c-terminal truncation of e2 at residue 661 or 715 (position on the polyprotein) leads to secretion, consistent with deletion of a proposed hydrophobic transmembrane anchor sequence. we demonstrate cell surface expression of a chimeric glycoprotein consisting of e2 residues 384 to 661 fused to the transmembrane and cytoplasmic domains of influenza a virus hemaggluti ... | 1999 | 10400776 |
| mutagenesis of the ns2b-ns3-mediated cleavage site in the flavivirus capsid protein demonstrates a requirement for coordinated processing. | analysis of flavivirus polyprotein processing has revealed the presence of a substrate for the virus-encoded ns2b-ns3 protease at the carboxy-terminal end of the c (capsid or core) protein. cleavage at this site has been implicated in the efficient generation of the amino terminus of prm via signal peptidase cleavage. yellow fever virus has four basic residues (arg-lys-arg-arg) in the p1 through p4 positions of this cleavage site. multiple alanine substitutions were made for these residues in or ... | 1999 | 10482557 |
| the severity of murray valley encephalitis in mice is linked to neutrophil infiltration and inducible nitric oxide synthase activity in the central nervous system. | a study of immunopathology in the central nervous system (cns) during infection with a virulent strain of murray valley encephalitis virus (mve) in weanling swiss mice following peripheral inoculation is presented. it has previously been shown that virus enters the murine cns 4 days after peripheral inoculation, spreads to the anterior olfactory nucleus, the pyriform cortex, and the hippocampal formation at 5 days postinfection (p.i.), and then spreads throughout the cerebral cortex, caudate put ... | 1999 | 10482632 |
| characterization of infectious murray valley encephalitis virus derived from a stably cloned genome-length cdna. | an infectious cdna clone of murray valley encephalitis virus prototype strain 1-51 (mve-1-51) was constructed by stably inserting genome-length cdna into the low-copy-number plasmid vector pmc18. designated pmve-1-51, the clone consisted of genome-length cdna of mve-1-51 under the control of a t7 rna polymerase promoter. the clone was constructed by using existing components of a cdna library, in addition to cdna of the 3' terminus derived by rt-pcr of poly(a)-tailed viral rna. upon comparison w ... | 1999 | 10567642 |
| mutagenesis of the signal sequence of yellow fever virus prm protein: enhancement of signalase cleavage in vitro is lethal for virus production. | proteolytic processing at the c-prm junction in the flavivirus polyprotein involves coordinated cleavages at the cytoplasmic and luminal sides of an internal signal sequence. we have introduced at the cooh terminus of the yellow fever virus (yfv) prm signal sequence amino acid substitutions (vpqaqa mutation) which uncoupled efficient signal peptidase cleavage of the prm protein from its dependence on prior cleavage in the cytoplasm of the c protein mediated by the viral ns2b-3 protease. infectiv ... | 2000 | 10590087 |
| perspectives for the treatment of infections with flaviviridae. | the family flaviviridae contains three genera: hepacivirus, flavivirus, and pestivirus. worldwide, more than 170 million people are chronically infected with hepatitis c virus and are at risk of developing cirrhosis and/or liver cancer. in addition, infections with arthropod-borne flaviviruses (such as dengue fever, japanese encephalitis, tick-borne encephalitis, st. louis encephalitis, murray valley encephalitis, west nile, and yellow fever viruses) are emerging throughout the world. the pestiv ... | 2000 | 10627492 |
| attenuation markers of a candidate dengue type 2 vaccine virus, strain 16681 (pdk-53), are defined by mutations in the 5' noncoding region and nonstructural proteins 1 and 3. | the genome of a candidate dengue type 2 (den-2) vaccine virus, strain pdk-53, differs from its den-2 16681 parent by nine nucleotides. using infectious cdna clones, we constructed 18 recombinant 16681/pdk-53 viruses to analyze four 16681-to-pdk-53 mutations, including 5' noncoding region (5'nc)-57 c-to-t, premembrane (prm)-29 asp-to-val (the only mutation that occurs in the structural proteins), nonstructural protein 1 (ns1)-53 gly-to-asp, and ns3-250 glu-to-val. the viruses were studied for pla ... | 2000 | 10708415 |