TitleAbstractYear(sorted ascending)
pathogenesis of foot-and-mouth disease in swine, studied by in-situ hybridization.eight 7-month-old pigs were inoculated intradermally with 10(3) plaque-forming units of foot-and-mouth disease virus, type o, and killed 24, 48, 72, or 96 h later. numerous tissues from each animal were collected and examined histopathologically and by in-situ hybridization to determine the presence of virus and its correlation with lesion development. the probe for in-situ hybridization was a biotinylated 500-base negative-sense transcription product corresponding to a portion of the gene encod ...19957490337
identification of the active-site residues of the 3c proteinase of foot-and-mouth disease identify the active-site residues of the 3c proteinase of foot-and-mouth disease virus (fmdv), we introduced mutations into the 3c coding region and examined the activity of mutant enzymes on various substrates. based on alignment of fmdv 3c with other picornavirus 3c proteinases and with the trypsin family of serine proteinases, mutations were introduced at residues presumed to be part of the catalytic triad, involved in substrate binding, or present in nonconserved regions. wild-type and mu ...19957491782
quantification of whole virus particles (146s) of foot-and-mouth disease virus in the presence of virus subunits (12s), using monoclonal antibodies in a sandwich elisa.this paper describes a method for the specific quantification of whole virions of foot-and-mouth disease (146s) in the presence of virus subunits (12s). the method involves the use of virus neutralising monoclonal antibodies directed against a linear epitope of the vp1 loop region of a type o virus. the monoclonal antibodies were used as both capture and detecting reagents (labelled with horse radish peroxidase) in a sandwich elisa. such monoclonal antibodies also have the advantage that they do ...19957491813
inducible expression of the p, v, and np genes of the paramyxovirus simian virus 5 in cell lines and an examination of np-p and np-v interactions.the p, v, and np genes of the paramyxovirus simian virus 5 (sv5) were cloned such that their expression was regulated by the tetracycline-controlled transactivator (m. gossen and h. bujard, proc. natl. acad. sci. usa 89:5547-5551, 1992), and mammalian cell lines that inducibly expressed individually the p, v, or np protein or coexpressed the p plus np or v plus np proteins were isolated. a plasmid that expresses the tetracycline-controlled transactivator linked, via the foot-and-mouth disease vi ...19957494313
protective effect of lidocaine in the experimental foot-and-mouth disease pancreatitis.experimental infection of mice with foot-and-mouth disease virus (fmdv) induces a necrotizing pancreatitis of the exocrinar portion of the organ. the lesions are characterized by vascular congestion, edema and interstitial polymorphonuclear leukocyte (pmn) infiltrates. when infected mice were treated with different amounts of lidocaine (a local anesthetic, chemically defined as a tertiary amide compound), reduction in intensity of the pancreatic necrosis and in the number of pmn were observed. e ...19957498445
molecular epidemiology of foot-and-mouth disease (fmd) in israel in 1994 and in other middle-eastern countries in the years 1992-1994.the reverse transcriptase-polymerase chain reaction (rt-pcr) and direct sequencing were employed in the diagnosis and typing of foot-and-mouth disease virus (fmdv) in samples taken during the 1994 disease outbreak in israel. using pcr, virus isolation and serological methods it was shown that the 1994 disease outbreak in israel and other middle-eastern countries was caused by o1 type virus. direct pcr sequencing of vp1 genes and homology analysis of the virus isolates revealed that there were tw ...19957503679
rapid detection and characterization of foot-and-mouth disease virus by restriction enzyme and nucleotide sequence analysis of pcr products.reverse transcription coupled with pcr was used for the detection of foot-and-mouth disease virus serotypes a, c, and o in organ extracts from experimentally infected cattle. primers were selected from conserved sequences flanking the genome region coding for the major antigenic site of the capsid located in the c-terminal part of viral protein 1 (vp1). because this region of the capsid is highly variable its coding sequence is considered to be the most appropriate for the characterization of vi ...19957714205
comparative between-laboratory trials of the liquid-phase blocking sandwich elisa for the detection of antibodies to foot-and-mouth disease virus.fifty bovine serum samples were tested for the presence or amounts of antibodies to foot-and-mouth disease (fmd) virus serotypes a, o and c by the liquid-phase blocking sandwich elisa (lpb-elisa) using reagents prepared by the world reference laboratory for foot-and-mouth disease (wrl) in pirbright, u.k. twenty of the sera had been collected before extensive vaccination with a commercial inactivated trivalent fmd vaccine was ceased and the remaining thirty originated from animals which had not b ...19957716862
optimization of an in situ hybridization technique for the detection of foot-and-mouth disease virus in bovine tissues using the digoxigenin in situ hybridization technique has been optimised for use on paraffin-embedded sections of tissues collected from cattle infected experimentally with foot-and-mouth disease virus type o1bfs. tissue was collected 5 days after infection by direct contact. in situ hybridization was carried out using an rna probe corresponding to a region of the 3d gene which codes for the rna polymerase, and labelled with digoxigenin. consistent, reproducible signal was detected within the epithelial layers of ...19957730440
cleavage of transcripts of foot and mouth disease virus (fmdv), asia1 serotype, by ribozymes targeted to the vp3 and vp4 genes.two ribozyme genes were designed to cut within the vp4 and vp3 sequences of foot and mouth disease virus (fmdv) asia1 serotype genome. the two genes were synthesized and cloned into pbluescript under the control of the t3 promoter. the ribozyme designed to cut the vp4 gene contained two catalytic sequences targeted to two guc triplets that are 16 bases apart. the second ribozyme, intended to cut vp3, contained one catalytic sequence. ribozymes obtained from run-off transcription from both plasmi ...19957732660
foot-and-mouth disease virus lb proteinase can stimulate rhinovirus and enterovirus ires-driven translation and cleave several proteins of cellular and viral origin.rhinovirus and enterovirus 2a proteinases stimulate translation initiation driven from the cognate internal ribosome entry segment (ires) (s. j. hambidge and p. sarnow, proc. natl. acad. sci. usa 89:10272-10276, 1992; h.-d. liebig, e. ziegler, r. yan, k. hartmuth, h. klump, h. kowalski, d. blaas, w. sommergruber, l. frasel, b. lamphear, r. rhoads, e. kuechler, and t. skern, biochemistry 32:7581-7588, 1993). given the functional similarities between the foot-and-mouth disease virus (fmdv) l prote ...19957745693
large deletions in the 5'-untranslated region of foot-and-mouth disease virus of serotype c.nucleotide sequences of the 5'-untranslated region (5'-utr), at the 3'-side of the poly c tract, have been compared for 21 isolates of foot-and-mouth disease virus (fmdv) of serotype c from europe, south america and the philippines. a deletion of 43 nucleotides is present in the european isolates as compared with most american isolates. a larger deletion of 86 nucleotides is present in some viruses from south america and the philippines. these deletions include the loss of one or two pseudoknot ...19957762289
detection of foot-and-mouth disease virus-infected cattle by assessment of antibody response in oropharyngeal fluids.the detection of foot-and-mouth disease virus (fmdv)-persistent carriers among convalescent ruminants is of paramount importance in the aftermath of a field outbreak. to this purpose, fmdv-specific antibody should be investigated first, since virus isolation procedures from such carriers are seriously constrained. the complexity of the overall picture may be compounded by possible emergency vaccinations in the affected areas at the beginning of the outbreak. in this case, it is suggested that mu ...19957699071
interaction of eukaryotic initiation factor eif-4b with a picornavirus internal translation initiation site.we studied the interaction of cellular proteins with the internal ribosome entry site (ires) of foot-and-mouth disease virus by uv cross-linking and observed specific binding of a 80-kda protein contained in cytosolic hela cell extract and in rabbit reticulocyte lysate. binding of the protein was dependent on the presence of atp. immunoprecipitation with eif-4b antiserum revealed that the protein is identical to the initiation factor eif-4b. deletions in the 3' part, but not in the 5' part, of t ...19957707504
a review of the possible mechanisms for the persistence of foot-and-mouth disease virus. 19957867727
genome variation in the sat types of foot-and-mouth disease viruses prevalent in buffalo (syncerus caffer) in the kruger national park and other regions of southern africa, 1986-93.dideoxy nucleotide sequencing of a portion of the 1d gene of sat-type foot-and-mouth disease viruses (fmdv) was used to derive phylogenetic relationships between viruses recovered from the oesophageo-pharyngeal secretions of buffalo in the kruger national park as well as several other wildlife areas in southern africa. the three serotypes differed from one another by more than 40% while intratypic variation did not exceed 29%. within each type, isolates from particular countries were more closel ...19957867739
proteolytic cleavage of initiation factor eif-4 gamma in the reticulocyte lysate inhibits translation of capped mrnas but enhances that of uncapped mrnas.infection of cells with the foot-and-mouth-disease virus, a member of the picornavirus family, results in the shut-off of host protein synthesis. a major contributory mechanism is the proteolytic destruction of the gamma subunit of the complex eif-4, which functions in translation to promote the binding of the 43s ribosomal preinitiation complex to the 5' end of the cellular mrna molecules bearing a 5' terminal cap structure. picornavirus rna molecules, which are uncapped, use a distinct mechani ...19957885827
foot-and-mouth disease virus undergoes restricted replication in macrophage cell cultures following fc receptor-mediated adsorption.we have previously reported that foot-and-mouth disease virus (fmdv) can enter an fc receptor (fcr)-expressing cell line by antibody-dependent enhancement. since fmdv can establish a persistent infection in animals in the presence of high levels of neutralizing antibodies (carrier state), we examined macrophages for their ability to be infected by the virus in the presence of antibody. the murine macrophage cell line p388d1 or porcine macrophage-monocytes isolated from peripheral blood were incu ...19957886954
direct evaluation of the immunodominance of a major antigenic site of foot-and-mouth disease virus in a natural host.the immunodominance of a major antigenic site of foot-to-mouth disease virus (fmdv) (serotype c; clone c-s8c1) in a natural host has been evaluated by serum immunoglobulin fractionation. nineteen sera from either convalescent or vaccinated swine were fractionated by affinity chromatography using a synthetic peptide representing antigenic site a (the g-h loop of capsid protein vp1) coupled to a sepharose matrix. antigen-binding and neutralizing activities of serum fractions were quantitated. on a ...19957831785
characterization of an acid-resistant mutant of foot-and-mouth disease virus.a foot-and-mouth disease virus mutant which is stable at ph 6.4 has been isolated from a virus of serotype a. in contrast to the parent (p) virus, which gave a mixture of large and small plaques in bhk21 cells and in a bovine kidney cell line, the acid-resistant (ar) virus gave small plaques which did not increase markedly in size after 24 hr. the infectivity titer of the acid-resistant virus was about 100-fold lower in suckling mice than in bhk21 cells, whether the inoculation was made intraper ...19957831827
sequences derived from the highly antigenic vp1 region 140 to 160 of foot-and-mouth disease virus do not prime for a bovine t-cell response against intact virus.although vp1 region 140 to 160 of foot-and-mouth disease virus (fmdv) is able to elicit neutralizing antibody in cattle, the protection against virus challenge that is conferred by peptide immunization is often poor. here, we show that bovine t cells primed with peptides derived from this region generally show no reactivity to intact fmdv. in contrast, t-cell epitope vp4[20-34] is able to prime for a virus-specific response.19957769713
neutralizing activity in bovine secretions against foot-and-mouth disease virus. 19957779950
african swine fever interference with foot-and-mouth disease infection and seroconversion in pigs.initial oral infection of pigs with either highly virulent (l-60) or moderately virulent (dr-2) african swine fever virus (asfv), followed in 3 days with exposure to foot-and-mouth disease virus (fmdv) (tongue inoculation and contact), failed to cause fmdv infection or seroconversion in 18 of 22 l-60-infected pigs and 13 of 34 dr-2-infected pigs. of the 13 dr-2-infected pigs remaining free of foot-and-mouth disease (fmd), 2 pigs survived to 24 days without antibody to fmdv, despite constant cont ...19957779962
african swine fever virus infection of skin-derived dendritic cells in vitro causes interference with subsequent foot-and-mouth disease virus infection.highly purified skin-derived dendritic cells (sddcs) isolated from swine skin by a simple novel method were cultured for 24 hours before independent or sequential inoculation with african swine fever virus (asfv) and foot-and-mouth disease virus (fmdv). by avidin-biotin immunohistochemical staining, asfv antigen was detected in 50% of sddcs as early as 1.5 hours postinfection (hpi) and in 80% by 3 hpi when cytopathic effect was noted. cell lysis was detected with fmdv infection as early as 8 hpi ...19957779963
detection and subtyping of foot-and-mouth disease virus in infected cattle by polymerase chain reaction and amplified vp1 and accurate detection of foot-and-mouth disease (fmd) outbreaks is needed to limit spread of the disease by proper vaccination. the use of the polymerase chain reaction (pcr) has revolutionized the way in which viral diseases are diagnosed. sequence analysis of the amplified vp1 sequence can enable the classification of fmd virus detected in the morbid animal. pcr assays were carried out to identify the virus and its serotype in suspect animals from 2 outbreaks of fmd type o virus. sequenc ...19957779964
expression in escherichia coli and purification of biologically active l proteinase of foot-and-mouth disease virus.the foot-and-mouth disease virus (fmdv) lb gene was cloned into bacterial expression vectors under the control of a t7 rna polymerase promoter. the lb protein was expressed in both an in vitro transcription-translation system and in escherichia coli. in vitro expression of a construct containing the lb gene fused to a portion of the vp4 and 3d genes demonstrated cis cleavage activity that could be blocked by the thiol protease inhibitor e-64. lb expressed in e. coli was purified from the soluble ...19957785315
antibodies raised in a natural host and monoclonal antibodies recognize similar antigenic features of foot-and-mouth disease virus.swine polyclonal antibodies directed against a major antigenic site (site a) of foot-and-mouth disease virus (fmdv) of serotype c, and monoclonal antibodies (mabs) which recognize different epitopes within this site, have been compared with regard to reactivity with a panel of synthetic peptides. the peptides used represent different segments or variant sequences of site a, and their reactivities reflect differences in antigenic specificity. the results indicate a remarkable immunochemical simil ...19957793064
serial passage in tissue culture of mixed foot-and-mouth disease virus serotypes.the foot-and-mouth disease (fmd) virus field specimen sau/8/88 was previously shown to consist of a mixture of o and asia 1 serotypes [15]. in this study, plaques representing the o and asia 1 components isolated from the original epithelial virus suspension were used to construct mixtures of known ratios, and these were serially passaged in tissue culture. after each passage, the ratio of o to asia 1 virus was calculated. the two virus populations were shown to be cycling through time. this cyc ...19957794118
ompa fusion proteins for presentation of foreign antigens on the bacterial outer membrane.the ompa genes of escherichia coli and shigella dysenteriae have been used to construct a group of enterobacterial surface expression vectors for foreign genes. linker oligonucleotides were inserted into the sequence corresponding to the third or fourth outer domain to allow in-frame sandwich fusion of foreign genes or epitopes into ompa. influenza haemagglutinin was inserted without its leader peptide and anchor sequences and shown to be transferred as an ompa fusion protein to the bacterial su ...19957796962
viral rna modulates the acid sensitivity of foot-and-mouth disease virus capsids.foot-and-mouth disease virus (fmdv) manifests an extreme sensitivity to acid, which is thought to be important for entry of the rna genome into the cell. we have compared the low-ph-induced disassembly in vitro of virions and natural empty capsids of three subtypes of serotype a fmdv by enzyme-linked immunosorbent assay and sucrose gradient sedimentation analysis. for all three subtypes (a22 iraq 24/64, a10(61), and a24 cruzeiro), the empty capsid was more stable by 0.5 ph unit on average than t ...19957983739
functional analysis of the two alternative translation initiation sites of foot-and-mouth disease virus.the effect of deletion of each of the two authentic polyprotein translation initiation sites of foot-and-mouth disease virus on viral protein synthesis and replication was analyzed. deletion of either the first or the second initiation site led to the expression of only one form of the leader protein, l or l', respectively, but in vitro processing of the viral polyprotein and cleavage of eif-4 gamma were not affected by either deletion. whereas rna in which the first translation initiation site ...19957983755
cyclic peptides as conformationally restricted models of viral antigens: application to foot-and-mouth disease virus.conformationally restricted cyclic peptide mimics of the antigenic site a of foot-and-mouth disease virus serotype c-s8c1 have been designed, first by comparison to the three-dimensional structure of the o1bfs serotype, later more accurately on the basis of x-ray diffraction data from a complex between a linear peptide reproducing site a and an fmdv-derived monoclonal antibody fab fragment. a variety of cyclization strategies have been attempted, both in solution and in the solid phase, involvin ...19959346844
improved mimicry of a foot-and-mouth disease virus antigenic site by a viral peptide displayed on beta-galactosidase surface.a major antigenic site (site a) of foot-and-mouth disease virus includes multiple overlapping epitopes located within the flexible g-h loop of capsid protein vp1. we have studied the antigenicity of several recombinant e. coli beta-galactosidases displaying the site a from a serotype c virus in different surface regions of the bacterial enzyme. in each one of the explored insertion sites, the recombinant peptide shows different specificity with a set of anti-virus monoclonal antibodies directed ...19959634810
structure and immunogenicity of experimental foot-and-mouth disease and poliomyelitis vaccines.the physico-chemical properties and immunogenicity of experimental vaccines against foot-and-mouth disease (fmd) and poliomyelitis, prepared by treatment of the viruses with n-acetylethyleneimine (aei), formaldehyde or neutral red, have been studied. none of these reagents affects the rate of sedimentation of the particles or their reaction with antibody against the major immunogenic sites. fmd vaccines prepared by inactivation with aei or neutral red, behaved like the untreated virus, in that t ...19958578849
the persistence of foot-and-mouth disease virus on wool.five suffolk sheep, held in a high-security isolation room, were exposed for 2 hours to the aerosol of 3 mature pigs that had been infected with foot-and-mouth disease virus (fmdv), strain o1-bfs. the fleeces of 3 of the sheep were contaminated with fmdv at 2 days post exposure (dpe), while at 5 dpe the fleeces of all 5 sheep were more extensively, and more heavily, contaminated. the persistence of fmdv on contaminated wool was examined in vitro using multiple 0.5 g samples of merino wool that w ...19958579558
[diagnosis of contagious diseases in animals using pcr].the pcr is used for diagnostic purposes as it allows to detect infections agents within a much shorter time than by cultural isolation. in addition, it can detect non-infectious viruses and bacteria in clinical samples. these advantages are important factors in the diagnosis of highly contagious animal diseases (mainly caused by viruses) since a rapid laboratory diagnosis will allow to take immediate disease control actions. pcr is routinely used at the institute of african and classical swine f ...19958584867
assessment of foot and mouth disease vaccine potency by liquid-phase blocking elisa: a proposal for an alternative to the challenge procedure in argentina.the lowest expected protection (lep) at a 95% confidence of 245 foot and mouth disease (fmd) commercial vaccines was calculated from the titres of liquid-phase blocking sandwich elisa (lpelisa) of cattle sera obtained from 3920 animals at 60 days post-vaccination (d.p.v.) and challenged with live virus at 90 d.p.v. it was found that lep evaluation is highly specific (i.e. it is able to predict the failure in 100% of the cases) although its ability to predict the challenge (pg test) approval (i.e ...19958585292
structural comparison of two strains of foot-and-mouth disease virus subtype o1 and a laboratory antigenic variant, g67.foot-and-mouth disease viruses (fmdvs) are members of the picornavirus family and cause an economically important disease of cloven-hoofed animals. to understand the structural basis of antigenic variation in fmdv, we have determined the structures of two viruses closely related to strain o1bfs whose structure is known.19958590018
selection of vaccine strains of foot and mouth disease virus for use in southern the countries of southern africa, types sat 1, sat 2 and sat 3 (sat: southern african territories) of foot and mouth disease (fmd) virus are the most widely represented, especially the sat 2 virus. since 1982, examinations have been conducted on 139 isolates of these virus types. other viruses, types o and a, have been detected in the north of this area. the typing and sub-typing of viruses with the complement fixation (cf) test can be improved by using panels of monoclonal antibodies (mabs), ...19958593387
serological comparison of type asia 1 foot and mouth disease virus isolates from thailand.antigenic variation of type asia 1 foot and mouth disease (fmd) virus in thailand was examined using a total of 50 field viruses isolated between 1986 and 1992. a two-dimensional serum neutralisation test was used to calculate r values for comparison of these isolates with a reference vaccine strain, asia 1 bangkok 1960 (bkk/60). viruses were also compared to two field isolates, asia 1 36-2/88 and asia 1 45/88, and some were compared to another vaccine strain, asia 1 nakhon pathom 1984 (npt/84). ...19958593388
serological comparison of type a foot and mouth disease virus isolates from thailand.antigenic variation of type a foot and mouth disease (fmd) virus in thailand was examined using a total of 82 field viruses isolated between 1986 and 1989. a two-dimensional serum microneutralisation test was used to compare these isolates to a reference strain, a15 bangkok 1960 (a bkk/60). viruses regarded as unrelated to a bkk/60 were compared to another reference strain, a22 nakhon pathom 1986 (a npt/86). this approach divided the viruses into two groups. most of the viruses shared a close an ...19958593389
hepatitis b virus core particles as epitope carriers.hbv core (hbc) particle is one of the most intensively studied particulate carriers for the insertion of foreign peptide sequences. recombinant hbc protein expressed from the cloned gene undergoes the correct folding in a large variety of bacterial, yeast, insect and mammalian cells. unique assembly properties and shape of 30/34-nm hbc particles allow substantial insertions into their primary structure without loss of their capsid-forming ability. n- and c-terminal regions, as well as the immuno ...19958666525
identification of native foot-and-mouth disease virus non-structural protein 2c as a serological indicator to differentiate infected from vaccinated livestock.cattle and pigs which have been vaccinated against foot-and-mouth disease can be distinguished from convalescent animals by radio-immunoprecipitation and sodium dodecyl sulphate polyacrylamide gel electrophoresis of the virus-induced proteins reacting with the respective sera. baby hamster kidney cells infected with foot-and-mouth disease virus (fmdv) (serotype a24) were labelled with 35s-methionine and the virus-induced proteins were precipitated with sera from vaccinated and subsequently chall ...19958525090
localization of foot and mouth disease virus rna in tissue culture infected cells via in situ polymerase chain reaction.foot and mouth disease virus rna was visualized in infected primary tissue culture cells by in situ pcr incorporating digoxigenin-labeled dutp. the viral rna polymerase gene was used as a target for amplification. infected cells revealed cytoplasmic staining, predominantly perinuclear. the intensity of staining was in proportion to the degree of cytopathology observed and similar to the results obtained using immunoperoxidase staining. the in situ pcr technique for fmdv detection could be applie ...19958530568
sequence identification of antigenic variants in plaque isolates of foot-and-mouth disease virus.foot-and-mouth disease virus isolates frequently contain mixtures of antigenic variants. using synthetic mixtures of two 'pure' viruses which differed at one amino acid of the major epitope, it was found that a minor component present as 10% or less of the mixture would be undetected by nucleic acid sequencing.19958537465
a highly divergent antigenic site of foot-and-mouth disease virus retains its immunodominance.the ability of a highly divergent antigenic site of foot-and-mouth disease virus (fmdv) of serotype c to elicit neutralizing antibodies has been evaluated in mice and rabbits. the viruses compared, fmdv c-s8c1 and hr, differ in a single amino acid replacement in their capsid proteins, but represent two extreme antigenic specificities of the major antigenic site a of fmdv type c. both, studies of cross-neutralization of homologous and heterologous virus, and fractionation of site a-specific antib ...19958546800
serological study of type a indian foot-and-mouth disease virus isolates.the antigenic relationship of sixty type a foot-and-mouth disease (fmd) viruses isolated between 1968 and 1993 has been determined with reference to a post-vaccinal bovine serum produced against type a ind 17/82. a micro-neutralization test and elisa were used to compare isolates. analysis of the results indicated that there was a positive correlation between the data from the two methods. the study indicated that type a ind 17/82 had a broad immunogenic spectrum and could be considered as a can ...19958825299
assembly of foot-and-mouth disease virus empty capsids synthesized by a vaccinia virus expression system.cdna cassettes encoding the foot-and-mouth disease virus (fmdv) structural protein precursor (p1-2a) together with the 3c protease, which cleave this molecule to 1ab, 1c and 1d, were constructed. these cassettes were introduced into vaccinia virus (vv) transfer vectors. attempts to isolate recombinant vvs constitutively expressing these cassettes were unsuccessful. however, when the p1-2a-3c cassette was placed under the control of the bacteriophage t7 promoter, stable vv/fmdv recombinants were ...19958847514
susceptibility of llamas (lama glama) to infection with foot-and-mouth-disease experimental trial was conducted to evaluate the ability of foot-and-mouth-disease (fmd) virus (serotypes a79, c3, o1) to infect susceptible llamas exposed either directly to affected livestock, or indirectly to llamas that had been directly exposed to affected livestock. in addition, susceptible livestock species (cattle, pigs, goats, and sheep) were exposed to those llamas that had been both directly and indirectly exposed to the fmd virus to further look at potential transmission possibili ...19958594845
deconvolution of fully overlapped reflections from crystals of foot-and-mouth disease virus o1 g67.foot-and-mouth disease virus o(1) g67 forms crystals that appear similar to those of the closely related viruses o(1)k and o(1)bfs, both of which belong to space group i23. statistical disorder in the o(1) g67 crystals means, however, that the measured diffraction data possess higher symmetry consistent with point group 432. it is shown that this is due to intimate twinning, with mosaic blocks randomly distributed between the two orientations. this results in a twofold loss of information due to ...199515299317
strong buffering capacity of insect cells. implications for the baculovirus expression system.insect cells are widely used for expression of a variety of different proteins by using the baculovirus expression system. the applicability of this system depends on production of proteins which have biological properties similar to their native counterparts. one application has been the expression of viral capsid proteins and their assembly into empty capsid structures to provide new viral immunogens which retain complex antigenic sites. an important parameter for efficient folding and assembl ...199522359206
synthetic peptides.efforts to produce more stable and defined vaccines have concentrated on studying, in detail, the immune response to many infectious diseases in order to identify the antigenic sites on the pathogens that are involved in stimulating protective immumty. armed with this knowledge, it is possible to mimic such sites by producing short chains of amino acids (peptides) and to use these as the basis for novel vaccines. the earliest documented work on peptide immunization is actually for a plant virus, ...199621359696
genetic variation of the poliovirus genome with two vpg coding units.amongst the picornaviruses, poliovirus encodes a single copy of the genome-linked protein, vpg wheras foot-and-mouth disease virus uniquely encodes three copies of vpg. we have previously shown that a genetically engineered poliovirus genome containing two tandemly arranged vpgs is quasi-infectious (qi) that, upon genome replication, inadvertently deleted one complete vpg sequence. using two genetically marked viral genomes with two vpg sequences, we now provide evidence that this deletion occur ...19968598203
a protective anti-peptide antibody against the immunodominant site of the a24 cruzeiro strain of foot-and-mouth disease virus and its reactivity with other subtype viruses containing the same minimum binding sequence.a synthetic peptide vaccine of the general sequence cys-cys-(200-213)-pro-pro-ser-(l41-158)-pro-cys-gly(peptide a40), where the numbered residues refer to the vp1 sequence of foot-and-mouth disease virus (fmdv) strain a24 cruzeiro, has previously been shown to elicit neutralizing and protective antibodies in guinea-pigs and cattle. to examine this immunogenic tract in more detail monoclonal antibodies (mabs) were raised to this peptide. one such mab c1.1, which recognized the homologous peptide, ...19968609466
antibody and host cell recognition of foot-and-mouth disease virus (serotype c) cleaved at the arg-gly-asp (rgd) motif: a structural interpretation.foot-and-mouth disease virus (fmdv) of serotype c (isolate c-s8c1) was cleaved in situ by trypsin at the arg-gly-asp (rgd) motif, which is involved both in attachment of fmdv to cells and in recognition of a major antigenic site (site a) by antibodies. though 99.4% of the rgd moieties were cleaved, the virus remained infectious. a synthetic peptide which represented the sequence of the vp1 g-h loop of c-s8c1, including the rgd motif, greatly inhibited fmdv attachment to cells. the same peptide i ...19968627229
recognition of the initiation codon for protein synthesis in foot-and-mouth disease virus rna.foot-and-mouth disease virus (fmdv) rna utilizes two in-frame initiation codons to produce two precursor proteins with identical carboxy termini. the 5' untranslated region (5'utr) directs the ribosome to internal sequences without the need for a cap structure as used in host mrnas. the fmdv 5'utr was cloned upstream of the reporter gene chloramphenicol acetyltransferase (cat) in order to study the selection of initiation site and to facilitate quantification of the translation products. after i ...19968627230
recognition of foot-and-mouth disease virus and its capsid protein vp1 by bovine peripheral t lymphocytes.the role of t cells in immunity to foot-and-mouth disease virus is still poorly defined compared to that of the humoral response. in this paper we describe a systematic, longitudinal study on the cellular recognition of fmdv and its subunit protein vp1 by bovine peripheral blood t lymphocytes. multiple vaccination with a single virus serotype induced a serotype cross-reactive proliferative t cell repertoire that varied in magnitude between individual animals and with the serotype of the vaccine ...19968627261
detection of foot-and-mouth disease viral sequences in various fluids and tissues during persistence of the virus in assess whether foot-and-mouth disease virus (fmdv)-specific sequences could be identified in tissues from persistently virus-infected animals.19968633795
rapid and sensitive polymerase chain reaction based detection and typing of foot-and-mouth disease virus in clinical samples and cell culture isolates, combined with a simultaneous differentiation with other genomically and/or symptomatically related viruses.reverse transcription followed by the polymerase chain reaction method (pcr) allowed the detection of foot-and-mouth disease virus (fmdv), regardless of the serotype. a primer set corresponding to highly conserved regions of the 2b sequence was selected. by combining in a single reaction tube specific primer pairs for fmdv, swine vesicular disease virus, (svdv), encephalomyocarditis virus (emcv) and bovine viral diarrhea virus (bvdv), all four viruses could be identified and differentiated in on ...19968634024
the c-terminal domain of eukaryotic protein synthesis initiation factor (eif) 4g is sufficient to support cap-independent translation in the absence of eif4e.the foot and mouth disease virus, a picornavirus, encodes two forms of a cysteine proteinase (leader or l protease) that bisects the eif4g polypeptide of the initiation factor complex eif4f into n-terminal (nt) and c-terminal (ct) domains. previously we showed that, although in vitro cleavage of the translation initiation factor, eif4g, with l protease decreases cap-dependent translation, the cleavage products themselves may directly promote cap-dependent protein synthesis. we now demonstrate th ...19968635470
a 'mixed' self-assembled monolayer for an impedimetric immunosensor.a synthetic peptide with the amino acid sequence 135-154 of the capsid protein vp1 of the foot-and-mouth-disease virus was modified with omega-hydroxyundecanethiol and applied together with non-derivatised omega-hydroxyundecanethiol for consecutive adsorption onto gold electrodes according to self-assembling procedures. the binding of a specific antibody to prepared recognition layers could be monitored by measurement of impedance or capacitance. in order to avoid non-specific effects, all measu ...19968639283
chimeric hepatitis b virus core particles as probes for studying peptide-integrin rgd-containing epitope from the foot-and-mouth disease virus (fmdv) vp1 protein was inserted into the e1 loop of the hepatitis b virus core (hbc) protein. this chimeric protein was expressed at high levels in escherichia coli and spontaneously assembled into virus-like particles which could be readily purified. these fusion particles elicited high levels of both enzyme-linked immunosorbent assay- and fmdv-neutralizing antibodies in guinea pigs. the chimeric particles bound specifically to cul ...19968648742
porcine polypyrimidine tract-binding protein stimulates translation initiation at the internal ribosome entry site of foot-and-mouth-disease virus.the cdna for porcine polypyrimidine tract-binding protein (sptb) was cloned. the sptb amino acid sequence is highly homologous to the human ptb sequence (97% identity), and the sptb sequence corresponds to that of the longest human ptb, ptb4. the specificity of binding in the uv-crosslink of sptb to the internal ribosome entry site (ires) of foot-and-mouth-disease virus (fmdv) is similar to that of human ptb. purified recombinant sptb efficiently stimulates internal translation initiation direct ...19968654585
systematic replacement of amino acid residues within an arg-gly-asp-containing loop of foot-and-mouth disease virus and effect on cell recognition.the conserved arg-gly-asp (rgd) motif found in a hypervariable, mobile antigenic loop of foot-and-mouth disease virus (fmdv) is critically involved in virus attachment to cells by binding to an integrin, probably related to alphavbeta3. here we describe (i) the synthesis of 241 15-mer peptides, which represent this loop of fmdv (isolate c-s8c1) and single variants in which each amino acid residue was replaced by 16 others and (ii) the inhibitory activity of these peptides on the ability of fmdv ...19968662712
comparison of a radioactive and non-radioactive method for sequencing foot and mouth disease virus isolates.the authors compare the radioactive method of detecting foot and mouth disease virus sequence products with a non-radioactive, silver stain sequencing method. the latter was found to compare favourably to the radioactive technique for detecting such products. the silver stain sequencing method was simple and did not require expensive specialised equipment. this new approach will be particularly useful in developing countries, since the method does not depend on the availability of fresh radioact ...19969025139
the performance of southern african territories serotypes of foot and mouth disease antigen in oil-adjuvanted vaccines.the performance of selected oil adjuvants containing southern african territories (sat) serotypes of foot and mouth disease virus was assayed by testing antibody levels elicited in cattle, sheep and goats, and by testing protection of cattle on challenge. various oil adjuvant formulations were tested initially in cattle and guinea pigs, and compared with a standard alhydrogel and saponin-based (as) vaccine. a commercial double oil emulsion vaccine elicited higher antibody titres and a more prolo ...19969025141
evaluation of the presence and risk of foot and mouth disease virus by commodity in international trade.potential sources of foot and mouth disease (fmd) virus include semen from bulls, rams, goats and boars; embryos and ova from ruminants and pigs; meat and meat products and milk and milk products. the author discusses precautions to prevent the transmission of fmd via these commodities.19969025152
antiviral activity of crude extracts of guarea guidona.crude extracts of leaves and fruits of guarea guidona were tested for antiviral activity against pseudorabies virus and foot-and-mouth disease virus in the ib-rs-2 pig cell line and against bovine herpesvirus-1 (bhv-1) in the gbk bovine cell line. the highest nontoxic doses of extracts from fruits and leaves were 125 micrograms/ml and 500 micrograms/ml. respectively. crude extracts presented antiviral activity against pseudorabies virus with a decrease in virus titer of 3.0 log units at 500 micr ...19969033817
emerging foot-and-mouth disease virus variants with antigenically critical amino acid substitutions predicted by model studies using reference of the major obstacles to the design of effective antiviral vaccines is the frequent generation of antigenic viral variants in the field. the types of variants that will become dominant during disease outbreaks is often unpredictable. however, here we report the genetic and antigenic characterization of emerging foot-and-mouth disease virus (fmdv) variants with antigenically critical amino acid substitutions predicted by model studies using reference viruses and monoclonal antibodies. the ne ...19968852403
mimicry of viral epitopes with retro-inverso peptides of increased stability.two major limitations to the use of peptides as synthetic vaccines are their poor immunogenicity and low antigenic cross-reactivity with the epitopes of virus particles. recently it has been shown that retro-inverso peptides corresponding to an immunodominant epitope of foot-and-mouth disease virus (fmdv) are able to mimic the structure and antigenic activity of natural l-peptides [1]. a series of l- and retro-inverso peptides of the loop 141-159 of the vp1 protein of fmdv has been synthesized. ...19968854029
antigenic analysis of type o foot-and-mouth disease virus in the persistently infected bovine.the antigenic profiles of serotype o strains of fmdv collected from the oropharynx of persistently infected cattle were defined with a panel of monoclonal antibodies (mab's) in an indirect antigen-trapping elisa. the mab profiling showed no significant loss of reactivity in two neutralising antigenic sites of persistent fmdv isolates collected over a period of eight months. early and late serum taken from a carrier animal showed similar neutralising activity against early and late carrier isolat ...19968856023
the position of the heterologous domain can influence the solubility and proteolysis of beta-galactosidase fusion proteins in e. coli.the vp1 protein (23 kda) of the foot-and-mouth disease virus has been produced in mc1061 and bl21 e. coli strains as beta-galactosidase fusion proteins, joined to either the amino and/or the carboxy termini of the bacterial enzyme. in bl21, devoid of la protease, all the recombinant fusion proteins are produced at higher yields than in mc1061, and occur mainly as inclusion bodies. the fusion of vp1 at the carboxy terminus yields a protease-sensitive protein whose degradation releases a stable, e ...19968861998
isotype-specific antibody responses to foot-and-mouth disease virus in sera and secretions of "carrier' and "non-carrier' cattle.isotype-specific antibody responses to foot-and-mouth disease virus (fmdv) were measured in the sera and upper respiratory tract secretions of vaccinated and susceptible cattle challenged with fmdv by direct contact or by intranasal inoculation. a comparison was made between cattle that eliminated fmdv and those that developed and maintained a persistent infection. serological and mucosal antibody responses were detected in all animals after challenge. iga and igm were detected before the develo ...19968870633
cloning and expression of a single-chain antibody fragment specific for foot-and-mouth disease virus.the gene for a single-chain antibody (vhk) to a conformational epitope on the type a12 foot-and-mouth disease virus (fmdv) particle was assembled and expressed in escherichia coli. the vhk, purified from periplasmic extracts immunoprecipitated virus as efficiently as its parental monoclonal antibody (mab) and exhibited the same binding specificity when tested against panel of natural and genetically engineered virus particles. the vhk neutralized type a12 virus in the presence of goat anti-mouse ...19968874516
intracellular membrane proliferation in e. coli induced by foot-and-mouth disease virus 3a gene products.during picornavirus infection replication of genomic rna occurs in membrane-associated ribonucleoprotein complexes. these replication complexes contain different nonstructural viral proteins with mostly unknown function. to examine the function of nonstructural picornaviral proteins in more detail, cdna of foot-and-mouth-disease virus (fmdv) strain o1 lausanne was cloned into lambda zap ii, and different parts of the p3-coding sequence were expressed in e. coli by the t7 polymerase system. expre ...19968879115
crystallization and preliminary x-ray diffraction studies of the lb proteinase from foot-and-mouth disease virus.different crystal forms of the c23a mutant from the leader proteinase of foot-and-mouth disease virus were obtained by the hanging drop vapor diffusion technique, using mgcl2 and peg 6000 as precipitants. well-developed crystals, with cubic morphology growing to approximately 1.0 mm3 in size, presented a large unit cell parameter of 274.5 a and diffracted to, at most, 5 a resolution. a second type of crystal had a tetragonal appearance and these were obtained in droplets soaked in a silica gel m ...19968880919
stability of foot-and-mouth disease virus, its genome and proteins at 37 degrees c.infectivity titers of foot-and-mouth disease virus (fmdv) types asia 1 and 0 were reduced by 4 and 2 log units, respectively, after incubation at 37 degrees c for 12 hrs. the stability of the fmdv rna genome at 37 degrees c was studied using 32p-labelled virus. the rna of fmdv type 0 was found to be more stable than that of type asia 1. oligo(dt)-cellulose chromatography showed that 21% and 31% of the labelled rna were bound to the column in the case of types asia 1 and 0, respectively. possible ...19968886092
foot-and-mouth disease virus 2a protease mediates cleavage in attenuated sabin 3 poliovirus vectors engineered for delivery of foreign antigens.poliovirus vectors are being studied as potential vaccine delivery systems, with foreign genetic sequences incorporated as part of the viral genome. the foreign sequences are expressed as part of the viral polyprotein. addition of proteolytic cleavage sites at the junction of the foreign polypeptide and the viral proteins results in cleavage during polyprotein processing. the ability of foot-and-mouth disease virus (fmdv) 2a to mediate proteolytic cleavage in the context of poliovirus vectors wa ...19968892938
increase of murine splenic natural antibody-secreting cells after cyclophosphamide treatment.administration of a low sub-immunosuppressive dose of cyclophosphamide (cy) to naive mice induced a marked increase in the number of splenic cells forming natural antibodies against unrelated antigens such as foot-and-mouth disease virus, keyhole limpet hemocyanin, horseradish peroxidase, or bovine serum albumin, as determined by an enzyme-linked immunosorbent assay spot technique. these results suggest that in mice there exists a repertoire of b cells forming natural antibodies which is restrai ...19968906754
peptide display on functional tailspike protein of bacteriophage p22.the tailspike protein (tsp) of salmonella typhimurium p22 bacteriophage is a multifunctional homotrimer, 6 copies of which are non-covalently attached to the capsid to form the virion tail in the last reaction of phage assembly. an antigenic peptide of foot-and-mouth disease virus (fmdv), aa 134-156 of protein vp1, has been joined to the carboxy terminus of tsp, and produced as a fusion protein in escherichia coli directed by the trp promoter. the resulting fusion protein is soluble, stable, non ...19968918257
antigenically profound amino acid substitutions occur during large population passages of foot-and-mouth disease virus.foot-and-mouth disease virus (fmdv) with amino acid substitutions next to the highly conserved r-g-d motif were isolated following large population passages of the virus (n. sevilla and e. domingo, 1996, j. virol., in press). reactivity with a panel of monoclonal antibodies which recognize different epitopes within site a was abolished or highly diminished in the mutants. this provides direct evidence of a drastic antigenic change occurring in the absence of selection by antibodies. molecular mo ...19968918927
antigenicity of a viral peptide displayed on beta-galactosidase fusion proteins is influenced by the presence of the homologous partner protein.several beta-galactosidase fusion proteins have been constructed containing the entire vp1 protein from foot-and-mouth disease virus (fmdv) [corchero et al. (1996) j. biotechnol. in press]. the antigenicity of the major immunodominant site a (13 amino acids in length) within the vp1 protein has been studied in competitive elisa using a panel of seven monoclonal antibodies elicited against the whole virus and recognizing b-cell epitopes within this site. none of the fusion proteins is able to rep ...19968931330
construction of a chimeric theiler's murine encephalomyelitis virus containing the leader gene of foot-and-mouth disease virus.the foot-and-mouth disease virus (fmdv) leader coding region (lb) was cloned into a full-length cdna of the da strain of theiler's murine encephalomyelitis virus (tmev) replacing the complete l coding region of tmev. this construct, pdafssc1-lb, was engineered to contain cleavage sites, at the 3' end of the lb coding region, for both the fmdv lb and the tmev 3c proteases. transcripts derived from this construct were translated in a cell-free system. analysis of the translation products showed ef ...19968941332
genetic lesions associated with muller's ratchet in an rna virus.the molecular basis of muller's ratchet has been investigated using the important animal pathogen foot-and-mouth disease virus (fmdv). clones from two fmdv populations were subjected to serial plaque transfers (repeated bottleneck events) on host bhk-21 cells. relative fitness losses were documented in 11 out of 19 clones tested. small fitness gains were observed in three clones. one viral clone attained an extremely low plating efficiency, suggesting that accumulation of deleterious mutations h ...19968951375
converging antigenic structure of a recombinant viral peptide displayed on different frameworks of carrier proteins.a peptide reproducing the g-h loop amino acid sequence of foot-and-mouth disease virus vp1 protein was fused to the solvent-exposed c-terminus of the bacteriophage p22 tailspike protein [carbonell and villaverde (1996) gene, in press], a homotrimeric polypeptide with a strong beta-helical structure. this fusion does not interfere with the biological activities of the phage tail. the antigenic profile of the complex antigenic site a within the g-h loop has been determined by competitive elisa wit ...19968955340
[mechanism of retaining stability of foot-and-mouth disease virus during manufacturing dried concentrated preparations].removal of moisture from concentrated virus suspensions in a sequential manner using ultrafiltration, active ventilation and vacuum dehydration of concentrated powders enables us to obtain preparations with a residual content of moisture less than 1%, while the structure and properties of fmd virus are retained. mechanism of inactivation of fmd virus in drying is attributed to electrophysical processes associated with development of electric potentials in evaporated objects due to directional mo ...19968967068
immunogenicity of an aphthovirus chimera of the glycoprotein of vesicular stomatitis oligodeoxynucleotide coding for amino acids 139 through 149 of antigenic site a (asa) of the vp1 capsid protein of the foot-and-mouth disease virus c3 serotype (fmdv c3) was inserted into three different in-frame sites of the vesicular stomatitis virus new jersey serotype (vsv-nj) glycoprotein (g) gene cdna present in plasmid pkg97 under control of the bacteriophage t7 polymerase promoter. transfection of these plasmids into cv1 cells coinfected with the t7 polymerase-expressing vaccinia viru ...19968970972
structural analysis of the interaction of the pyrimidine tract-binding protein with the internal ribosomal entry site of encephalomyocarditis virus and foot-and-mouth disease virus rnas.initiation of translation of a subset of eukaryotic mrnas results from internal ribosomal entry. this process is exemplified by encephalomyocarditis virus (emcv), which contains an internal ribosomal entry site (ires) within its 5' nontranslated region that is approximately 450-nt long and consists of a series of stem-loops designated h-l. we have previously identified a cellular 58-kda polypeptide that binds specifically to this ires and that is implicated in its function as the pyrimidine trac ...19968972770
a recombinant, arginine-glycine-aspartic acid (rgd) motif from foot-and-mouth disease virus binds mammalian cells through vitronectin and, to a lower extent, fibronectin receptors.the cell-binding abilities of a recombinant, rgd-containing peptide from foot-and-mouth disease virus (fmdv) have been characterized in hela and bhk cells. this peptide represents the aa sequence of the solvent-exposed g-h loop of protein vp1 which is involved in cell recognition and infection. the efficiency of the viral motif in promoting cell attachment and spreading is comparable to that shown by fibronectin or vitronectin. cell binding is inhibited by a monoclonal antibody directed against ...19968973352
foot and mouth disease virus concentration and purification by affinity chromatography.foot and mouth disease virus, (fmdv) from a crude cell lysate was purified in a single step by affinity chromatography with heparin as a ligand. the virus eluted from an heparin-ultrogel a4r column at 1m sodium chloride in 10 mm sodium phosphate buffer, ph 7.0, while most cell protein and albumin did so at lower concentrations of sodium chloride in the same buffer. purity of the eluted fraction containing the virus was assessed by sds-page, hplc, ultracentrifugation, and uv absorption spectrum. ...19969100360
functional expression of a cattle mhc class ii dr-like antigen on mouse l cells.cattle dra and drb genes, cloned by reverse-transcription polymerase chain reaction, were transfected into mouse l cells. the cattle dr-expressing l-cell transfectant generated was analyzed serologically, biochemically, and functionally. sequence analysis of the transfected drb gene clearly showed showed that it was drb3 allele drb3(*)0101 , which corresponds to the 1d-ief-determined allele drbf3. 1d-ief analysis of the transfectant confirmed that the expressed dr product was drbf3. functional i ...19969110933
the solution structure of the immunodominant and cell receptor binding regions of foot-and-mouth disease virus serotype a, variant a.abstract: the solution structure of a 20 amino acid long peptide corresponding to the region 141-160 of the envelope protein vp1 from foot-and-mouth disease virus (fmdv) serotype a, variant a, has been determined by a combination of nmr experiments and computer calculations. the peptide contains both the immunodominant epitope as well as the sequence (rgd) used by the virus to bind the cell receptor in the initial stages of infection. these two sites have been shown to partially overlap. one hun ...19969225248
the solution conformational features of two highly homologous antigenic peptides of foot-and-mouth disease virus serotype a, variant a and usa, correlate with their serological properties.the solution structure of a peptide corresponding to the vp1 region 141-160 of foot-and-mouth disease virus (fmdv) serotype a variant usa has been studied by nmr and computer calculations and compared with the results from a study on a highly homologous peptide deriving from serotype a, variant a. the two peptides differ in their serological behavior and contain the immunodominant epitope of the virus which partly overlaps with its receptor binding region. distance constraints, derived both from ...19969225249
equine rhinovirus 1 is more closely related to foot-and-mouth disease virus than to other picornaviruses.equine rhinovirus 1 (erhv1) is a respiratory pathogen of horses which has an uncertain taxonomic status. we have determined the nucleotide sequence of the erhv1 genome except for a small region at the 5' end. the predicted polyprotein was encoded by 6741 nucleotides and possessed a typical picornavirus proteolytic cleavage pattern, including a leader polypeptide. the genomic structure and predicted amino acid sequence of erhv1 were more similar to those of foot-and-mouth disease viruses (fmdvs), ...19968577774
the use of cyclophosphamide as an enhancer of the vaccine against foot-and-mouth disease.the immunization of biungulate animals with killed foot-and-mouth disease virus (fmdv) requires periodic vaccinations due to a low vaccine immunogenicity. therefore, fmdv antigens need to be combined with adjuvants such as aluminium hydroxide, saponin or oil emulsions. animal handling for periodic inoculations, and the repeated doses of vaccines that have to be administered increase the commercialization costs. moreover, the use of adjuvants may induce adverse effects. in the present work we sho ...19968698098
assessment of variation in trypsin-sensitive neutralizable antigenic site of type o foot-and-mouth disease virus (fmdv) isolates using a mab-binding inhibition assay. 19968699017
alteration of the trypsin-sensitive antigenic site of foot-and-mouth disease virus following direct binding to an elisa plate. 19968699018
beta-galactosidase enzymatic activity as a molecular probe to detect specific antibodies.the main antigenic region of foot-and-mouth disease virus serotype c1, also called site a, has been inserted in zones of the beta-galactosidase important for the stabilization of the active site, causing important changes in the km and the specific activity of the resulting enzymes. the peptide is displayed at the surface of the recombinant proteins and, in all the cases, presents a good antigenicity. among the recombinant proteins constructed, in proteins m278vp1 and m275svp1 the peptide is ins ...19968702899
virulence as a positive trait in viral persistence.a population replacement experiment has been devised to test the ability of a challenge virus to replace the resident virus in a persistently infected cell culture. bhk-21 cells persistently infected with foot-and-mouth disease virus of serotype c (clone c-s8c1) were challenged with a large excess of either the parental foot-and-mouth disease virus c-s8c1, genetically marked variants differing in their degree of virulence, or a mutant rescued after prolonged persistence in bhk-21 cells. after ch ...19968709272
strategy for producing new foot-and-mouth disease vaccines that display complex epitopes.widely used inactivated vaccines for foot-and-mouth disease (fmd) induce protective immunity, but vaccine production plants and residual virus in the vaccine itself have been implicated in disease outbreaks. the structure of the fmd virion has been determined, and although much of the surface of the viral particle is produced by complex folding of the three surface-exposed capsid proteins (vp1-3), some surface regions representing important linear epitopes can be mimicked by recombinant proteins ...19968717390
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