split decomposition: a technique to analyze viral evolution.a clustering technique allowing a restricted amount of overlapping and based on an abstract theory of coherent decompositions of finite metrics is used to analyze the evolution of foot-and-mouth disease viruses. the emerging picture is compatible with the existence of viral populations with a quasispecies structure and illustrates various forms of evolution of this virus family. in addition, it allows the correlation of these forms with geographic occurrence.19938234292
transient inhibition of foot-and-mouth disease virus infection of bhk-21 cells by antisense oligonucleotides directed against the second functional initiator aug.the antiviral activity of antisense oligonucleotides corresponding to different regions of foot-and-mouth disease virus (fmdv) genome has been assessed in bhk-21 cells. the locations of the oligonucleotides used were: (i) two regions within the internal ribosome entry site (ires), involved in the regulation of the translation initiation of the viral polyprotein; (ii) each of the two functional initiator augs; (iii) an internal sequence of p2a gene; and (iv) a region at the 3' end non-coding regi ...19938250540
co-replication of several isotypes of foot-and-mouth disease virus.genome segments of the foot-and-mouth disease virus isolates o1lombardy and o3 venezuela that encode, among other products, capsid protein vp1 were amplified using pcr, and the products were cloned and sequenced. the alignment of up to 11 o3-specific sequences revealed six silent nucleotide changes a well as six changes that cause amino acid substitutions in capsid protein vp1 at positions 45, 83, 141, 145, 170 and 178. the heterogeneity of three o1-specific sequences consisted of seven silent e ...19938277282
viral antibodies in bovine fetuses in order to establish the prevalence of viral infections of the bovine fetus in argentina, a serological survey for antibodies against viral agents currently affecting cattle in this country was conducted. antibodies against foot-and-mouth disease virus (fmdv), bovine herpesvirus-1 (bhv-1), bovine leukaemia virus (blv), bovine rotavirus (brv), bovine coronavirus (bcv), bovine viral diarrhoea virus (bvdv) and parainfluenza-3 (pi-3) were investigated in a total of 315 fetal serum samples. conventi ...19938284507
effects of different continium dielectric models in a molecular dynamics and energy minimization study of the antigenic loop of foot-and-mouth disease virus.this study presents the influence of the dielectric constant on the final structure of the major antigenic loop of the fmdv serotype c. minimizations have been performed on the nine-residue peptide ac-tasargdla-nhme, using two expressions for the dielectric constant: a distance-independent (epsilon = kappa), and a distance-dependent (epsilon = kappa *r) forms, and for kappa values from 1 to 10. in addition, kappa = 40 and 80 has also been considered for the constant expression of the dielectrics ...19938286066
trans complementation by rna of defective foot-and-mouth disease virus internal ribosome entry site elements.a region of about 435 bases from the 5' noncoding region of foot-and-mouth disease virus rna directs internal initiation of protein synthesis. this region, termed the internal ribosome entry site (ires), is predicted to contain extensive secondary structure. precise deletion of five predicted secondary structure features has been performed. the mutant ires elements have been constructed into vectors which express bicistronic mrnas and assayed within cells. each of the modified ires elements was ...19948289373
foot-and-mouth disease virus particles contain replicase protein antibody against the escherichia coli-expressed rna polymerase of foot-and-mouth disease virus (fmdv) reacts with the virus in elisa and radioimmunoprecipitation experiments and with a protein of the disrupted virus particle in an immunoblot analysis. treatment of the virus with trypsin, which cleaves capsid protein vp1 and a 56-kda polypeptide present in trace amount in the particles, reduces the level of the reaction in elisa and radioimmunoprecipitation and eliminates the immunoblot reacti ...19948290591
avridine and lps from brucella ovis: effect on the memory induced by foot-and-mouth disease virus vaccination in mice.foot-and-mouth disease is one of the more economically important diseases among meat-producing biungulate species. in contrast to natural infection, current foot-and-mouth disease virus (fmdv) vaccines, prepared with inactivated virus and adjuvants, elicit short-lived protection. the immunomodulating effect on fmdv vaccines of avridine and lipopolysaccharide of brucella ovis (lps) was tested in a murine model. the duration of immunity, protection, stimulation of immunocompetent cells producing a ...19938296482
[a rapid solid-phase immunoenzyme method in the diagnosis of viral infections].an accelerated solid-phase enzyme-immunoassay has been developed which permits identification of antigens and antibodies to them within 30-40 min, even directly at the site of specimen collection. the method was tested on the models of foot-and-mouth disease virus, vesicular disease of swine, vesicular exanthema of swine, aujeszky's disease, leukemia, and coronavirus infection of cattle.19938303893
comparison of surface properties of picornaviruses: strategies for hiding the receptor site from immune surveillance.the surface topology and sequence conservation of different picornaviruses have been compared using molecular graphics and statistical analyses. the comparisons suggest that the canyons, surface depressions encircling the fivefold axes, are the sites of receptor attachment of enteroviruses as well as human rhinovirus (hrv). in hrv14, the receptor binding footprint extends beyond the canyon (olson et al. (1993), proc. natl. acad. sci. usa 90, 507-511), but these more exposed regions are not conse ...19938337843
antibody-complexed foot-and-mouth disease virus, but not poliovirus, can infect normally insusceptible cells via the fc receptor.poliovirus and foot-and-mouth disease virus (fmdv) initiate infection by binding to specific cell surface receptors, which is followed by a poorly understood disassembly process. to probe these early steps of infection, the ability of poliovirus and fmdv to infect cells following binding through an alternative receptor was examined. for these studies, a chinese hamster ovary (cho) cell line expressing the b2 isoform of the murine fc receptor (fcr) was used. both viruses were able to bind to this ...19938380665
methods used in the structure determination of foot-and-mouth disease virus.the structure of foot-and-mouth disease virus (fmdv) strain o1 bfs 1860 has been determined to 2.9 a resolution using the molecular-replacement method [acharya, fry, stuart, fox, rowlands & brown (1989). nature (london), 337, 709-716]. crystals of the virus with average dimensions 0.12 x 0.06 x 0.12 mm belong to space group i23, a = 345 a with 1/12 of the icosahedral particle per asymmetric unit giving fivefold noncrystallographic redundancy. oscillation diffraction photographs were collected at ...19938382928
phenotypic and functional characterization of mouse attenuated and virulent variants of foot-and-mouth disease virus type o1 campos.a series of genetically related variants arising from a parental wild-type isolate of o1 campos and its tissue culture adapted variant were differentiated by various cell culture markers (temperature sensitivity, plaque size, viral yield) and lethality in mice. these isolates were additionally characterized functionally and biochemically by examining poly(c) length, rna synthesis, protein synthesis, and cell receptor binding. in primary bovine kidney cells, the virulent isolates had greater leve ...19938384748
structure of a major immunogenic site on foot-and-mouth disease virus.attachment of foot-and-mouth disease virus (fmdv) to its cellular receptor involves a long and highly antigenic loop containing the conserved sequence, arg-gly-asp, a motif known to be a recognition element in many integrin-dependent cell adhesion processes. in our original crystal structure of fmdv the arg-gly-asp-containing loop ('the loop'), located between beta-strands g and h of capsid protein vp1, was disordered and hence essentially invisible. we previously surmised that its disorder is e ...19938385272
foot-and-mouth disease virus proteinase 3c inhibits translation in recombinant escherichia coli.escherichia coli cultures do not survive the expression of recombinant foot-and-mouth disease virus proteinase 3c. this effect is ascribed to degradation of bacterial protein(s), as concluded from the observation of gradual cessation of gene expression upon induction of 3c expression. most likely, translation inhibition is the cause of bacterial death, as (i) cell-free translation of the 3c gene was restored by additional bacterial ribosomes, (ii) ribosomes from proteinase 3c-producing cells dif ...19938386123
the two species of the foot-and-mouth disease virus leader protein, expressed individually, exhibit the same activities.initiation of protein synthesis on the foot-and-mouth disease virus rna occurs at two sites, thus, two forms of the leader protein, termed lab and lb, are produced. plasmids have been constructed which encode these proteins either together or individually. plasmids encoding the lab protein alone express a modified form of this protein in which the second methionine residue, which corresponds to the first amino acid of lb, is changed to an alternative residue. four different mutant forms of the l ...19938386879
design of primers for pcr amplification of highly variable genomes.a program to aid in the search of primers for specific polymerase chain reaction (pcr) amplification of highly variable genomes is presented. it involves the derivation of variability profiles to identify optimal regions for pcr amplification, taking into account stability of dna-primer hybrids. an application of the program to foot-and-mouth disease virus diagnosis is presented.19938386978
an indirect sandwich elisa for the identification of bovine indirect sandwich elisa is described for the detection of bovine enteroviruses. the assay was developed as an alternative to the complement fixation test and proved to be more sensitive and convenient. ten bovine enterovirus prototype strains were easily discriminated. no cross-reactions were observed with other picornaviruses including foot-and-mouth disease viruses, swine vesicular disease virus, porcine enteroviruses and bovine rhinovirus.19938388399
conserved tertiary structural elements in the 5' nontranslated region of cardiovirus, aphthovirus and hepatitis a virus rnas.statistical analyses of rna folding in 5' nontranslated regions (5'ntr) of encephalomyocarditis virus, theiler's murine encephalomyelitis virus, foot-and-mouth disease virus, and hepatitis a virus indicate that two highly significant folding regions occur in the 5' and 3' portions of the 5'ntr. the conserved tertiary structural elements are predicted in the unusual folding regions (ufr) for these viral rnas. the theoretical, common structural elements predicted in the 3' parts of the 5'ntr occur ...19938389442
a single nucleotide substitution in the internal ribosome entry site of foot-and-mouth disease virus leads to enhanced cap-independent translation in vivo.mutants of foot-and-mouth disease virus (fmdv) with altered biological properties can be selected during the course of persistent infection of bhk-21 cells with fmdv c-s8c1 (j. c. de la torre, e. martínez-salas, j. díez, a. villaverde, f. gebauer, e. rocha, m. dávila, and e. domingo, j. virol. 62:2050-2058, 1988). two nucleotide substitutions, u to c at position -376 and a to g at position -15, (counting as +1 the a of the first functional aug), were fixed within the internal ribosome entry site ...19938389904
detection of foot-and-mouth disease virus rna in clinical samples and cell culture isolates by amplification of the capsid coding region.foot-and-mouth disease is one of the most economically important virus diseases of livestock. two important requirements for the control of this disease are rapid laboratory diagnosis and epidemiological investigation. the use of the polymerase chain reaction method (pcr) to amplify specific nucleic acid regions offers the unique possibility of combining swift viral detection with the production of genetic material suitable for sequencing and other methods of molecular epidemiological analysis. ...19938391540
rhipicephalus zambeziensis unlikely to transmit foot-and-mouth disease virus.the potential of the ixodid tick, rhipicephalus zambeziensis, was investigated as a vector in the transstadial transmission of the foot-and-mouth disease virus by feeding nymphae on viraemic (log 1.0-4.0 tcid50/ml) cattle. suspensions were prepared, at various intervals after detachment, from pools of engorged nymphae--some of which were allowed to moult first. suspensions were inoculated into sucking mice, cell cultures and, in some cases, cattle to detect the fmd virus. newly moulted adult tic ...19938392681
the carrier state in foot and mouth disease--an immunological review.the carrier state in foot and mouth disease (fmd) is characterized by the asymptomatic low-level excretion of foot and mouth disease virus (fmdv) from the oropharynx of ruminants for periods that are species and virus strain-dependent. persistent infection with fmdv readily occurs following the failure of virus elimination at the acute stage of infection, a process thought to be mediated through the phagocytosis of antibody/virus immune complexes. recent evidence supports the view that carrier c ...19938392891
large-scale use of liquid-phase blocking sandwich elisa for the evaluation of protective immunity against aphthovirus in cattle vaccinated with oil-adjuvanted vaccines in argentina.specific serum activity levels against four reference strains of foot-and-mouth disease virus (fmdv) were evaluated from 1634 animals vaccinated with commercial quadrivalent oil vaccines and from 746 unvaccinated, naive animals, using the liquid-phase blocking sandwich elisa (lpelisa) test. cows from the fmdv-free area of argentina were tested for the absence of specific fmdv antibodies (sp fmdv abs) and those showing lpelisa titres < 1.0 were grouped in lots of 16 animals. they were vaccinated ...19938393607
a comparative study of the immune responses of sheep against foot-and-mouth disease virus types asia-1 and o peg-concentrated aluminium hydroxide gel and oil-adjuvanted vaccines.foot-and-mouth disease (fmd) vaccines prepared against types asia-1 and o peg-concentrated and adjuvanted with aluminium hydroxide gel were compared with oil-adjuvanted types asia-1 and o vaccines in sheep. the study was conducted by inoculating 0.5 ml of monovalent vaccine under laboratory conditions and 1 ml dose of bivalent vaccine in field conditions. the antibody responses were monitored by serum neutralization and elisa tests. the results indicate that peg-concentrated gel vaccine was of c ...19938393608
identification of a fifth neutralizable site on type o foot-and-mouth disease virus following characterization of single and quintuple monoclonal antibody escape mutants.a monoclonal antibody (c3) produced against foot-and-mouth disease virus type o1caseros was found to neutralize quadrivalent monoclonal antibody escape mutant (g67) of foot-and-mouth disease virus type o1kaufbeuren. this mutant had been characterized at the sequence level as having distinct changes affecting four non-overlapping neutralizable sites. the c3 monoclonal antibody was used to prepare a quintuple escape mutant from the g67 and a single escape mutant from the parental o1kaufbeuren viru ...19938393912
genetically engineered foot-and-mouth disease viruses with poly(c) tracts of two nucleotides are virulent in determine the role of the poly(c) tract found at the 5' end of the genome of foot-and-mouth disease virus, synthetic rnas (in vitro transcripts) with poly(c) tracts of different lengths have been produced and evaluated. rnas with poly(c) tracts of 35, 25, 16, 6, or 2 residues displayed similar specific infectivities in baby hamster kidney (bhk) cells. viruses recovered from cells transfected with in vitro transcripts containing 6 to 35 cs had properties similar to those of the wild-type virus ...19938394441
protection of swine against foot-and-mouth disease with viral capsid proteins expressed in heterologous systems.three groups of swine were each inoculated with a different antigen preparation of foot-and-mouth disease virus (fmdv) capsid proteins and challenged by contact exposure to animals infected with fmdv. one group of four animals was inoculated with an extract from cells infected with a recombinant baculovirus containing the fmdv p1-2a structural protein precursor gene and a portion of the p2 gene. two out of four animals were protected from clinical disease, but not from virus replication. a secon ...19938395128
the detection of foot-and-mouth disease virus in oesophageal-pharyngeal samples by a polymerase chain reaction technique.a polymerase chain reaction (pcr) technique was used to detect the presence of foot-and-mouth disease virus (fmdv) in oesophageal-pharyngeal(op) samples from experimentally infected steers. ten-fold dilutions of op samples were also diluted, inoculated onto lamb kidney cell cultures, and incubated overnight. the cultures that did not show overt cytopathogenic effects (cpe) of fmdv infection were frozen and thawed; both the fluid and the cell pellet were tested by the pcr technique. the pcr detec ...19938395537
network models for sequence evolution.we introduce a general class of models for sequence evolution that includes network phylogenies. networks, a generalization of strictly tree-like phylogenies, are proposed to model situations where multiple lineages contribute to the observed sequences. an algorithm to compute the probability distribution of binary character-state configurations is presented and statistical inference for this model is developed in a likelihood framework. a stepwise procedure based on likelihood ratios is used to ...19938395605
distinctive features of foot-and-mouth disease virus, a member of the picornavirus family; aspects of virus protein synthesis, protein processing and structure. 19938396787
cross-reactive idiotopes among anti-foot and mouth disease virus neutralizing antibodies.foot and mouth disease virus (fmdv) viral protein 1 is the only one of the four viral proteins (vp) that induces neutralizing antibodies as an isolated protein. a 32 amino acid (aa) residue (32dimer) of fmdv subtype a12 lp ab vp1 (aa 137-168) was immunogenic against the a12 subtype. three antibody populations each recognizing different epitopes on 32dimer were isolated by affinity chromatography (afc) from the serum of a steer which had been immunized with the 32dimer. the 32dimer contains an aa ...19938406565
recent advances in bovine vaccine technology.a description of new commercial and experimental vaccines for viral and bacterial diseases of cattle can be broadly divided into those used for both beef and dairy cows and those used predominantly in dairy cattle. for both types of cattle, newer and experimental vaccines are directed against several of the important viral (e.g., bovine herpesvirus 1, bovine viral diarrhea virus, bovine respiratory syncytial virus, parainfluenza type 3, and foot-and-mouth disease virus) and bacterial pathogens ( ...19938408872
molecular epidemiology of foot-and-mouth disease virus type o.a phylogenetic tree based on the vpi sequences of type o foot-and-mouth disease virus (fmdv) has been derived. direct sequencing of pcr products has been used to obtain the vp1 gene sequences of new isolates. the tree exhibits four main lineages that largely correlate with the geographical origin of isolates. the analysis supports a close relationship between european o1 field isolates and vaccine strains, with the exception of o thalheim aus/81 and o wuppertal ger/82 which were probably of non- ...19938409952
dilute passage promotes expression of genetic and phenotypic variants of human immunodeficiency virus type 1 in cell culture.we have studied the extent of genetic and phenotypic diversification of human immunodeficiency virus type 1 (hiv-1) upon 15 serial passages of clonal viral populations in mt-4 cell cultures. several genetic and phenotypic modifications previously noted during evolution of hiv-1 in infected humans were also observed upon passages of the virus in cell culture. notably, the transition from non-syncytium-inducing to syncytium-inducing phenotype (previously observed during disease progression) and fi ...19938474182
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
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
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
induced pocket to accommodate the cell attachment arg-gly-asp motif in a neutralizing antibody against foot-and-mouth-disease virus.the three-dimensional structure of the fab fragment of a neutralizing monoclonal antibody (sd6) elicited against foot-and-mouth disease virus (fmdv) has been determined at 2.5 a resolution and refined to a crystallography agreement r-factor of 0.186. the structure has been compared with that of the same fab molecule complexes with a 15 amino acid peptide (a15) representing a major antigenic site of fmdv, and determined at 2.8 a resolution. the fab quaternary structure, defined both by the elbow ...19968594203
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
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
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
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
amitraz effects on foot-and-mouth disease virus in mammalian cells in vitro.the toxicity of the acaricide amitraz and its effect on foot-and-mouth disease virus multiplication were evaluated in ib-rs-2 cells in vitro. a reduction of cell growth rate that was dependent on the dose and the length of treatment was observed in cells exposed to amitraz concentrations ranging from 20 to 50 micrograms/ml. foot-and-mouth disease virus infectivity remained essentially unchanged in cells exposed to amitraz (20 micrograms/ml) 24 hr prior to virus infection or after the adsorption ...19968723754
liquid-phase blocking sandwich enzyme-linked immunosorbent assay for detection of antibodies against foot-and-mouth disease virus in water buffalo develop and apply the liquid-phase blocking sandwich elisa (blocking-elisa) for the quantification of antibodies against foot-and-mouth disease virus (fmdv) strains o1 campos, a24 cruzeiro, and c3 indaial. design--antibody quantification.19968725810
absence of protein 2c from clarified foot-and-mouth disease virus vaccines provides the basis for distinguishing convalescent from vaccinated animals.we have recently reported that cattle and pigs which have been vaccinated against foot-and-mouth disease can be distinguished from convalescent animals by the absence of antibodies to viral non-structural protein 2c (lubroth and brown, res. vet. sci., 1995, 59, 70-78(1)). in this study, we show that the absence of 2c antibodies from the sera of vaccinated animals can be explained by the association of this viral protein with cellular debris which is separated from the virus harvest prior to inac ...19968735554
detection of antibodies against foot-and-mouth disease virus using a liquid-phase blocking sandwich elisa (lpbe) with a bioengineered 3d protein.a liquid-phase blocking sandwich enzyme-linked immunosorbent assay (elisa-3d) was developed to detect specific antibodies to the 3d protein in sera from foot-and-mouth disease (fmd) virus (fmdv)-infected animals. the assay uses a nonstructural 3d recombinant protein and two polyclonal antisera, one for capture (bovine) and the other for detector (guinea pig). the specificity of the assay was demonstrated by negative results with 101 sera of cattle from the fmd-free zone in argentina and with bov ...19968744733
persistent infection of african buffalo (syncerus caffer) with sat-type foot-and-mouth disease viruses: rate of fixation of mutations, antigenic change and interspecies transmission.transmission of a plaque-purified sat-2 foot-and-mouth disease virus (fmdv) occurred erratically from artificially infected african buffaloes in captivity to susceptible buffaloes and cattle in the same enclosure; in some instances transmission occurred only after contact between persistently infected carriers and susceptible animals lasting a number of months. because the rate at which fmdv mutations accumulated in persistently infected buffaloes was approximately linear (1.64 percent nucleotid ...19968757987
high-titer bicistronic retroviral vectors employing foot-and-mouth disease virus internal ribosome entry site.bicistronic retroviral vectors were constructed containing the foot-and-mouth disease virus (fmdv) internal ribosome entry site (ires) followed by the coding region of beta-galactosidase (beta-gal) or therapeutic genes, with the selectable neomycin phosphotransferase gene under the control of the viral long terminal repeat (ltr) promoter. lnfx, a vector with a multiple cloning site 3' to foot-and-mouth disease virus ires, was used to construct vectors encoding rat erythropoietin (ep), rat granul ...19968758998
equine rhinovirus serotypes 1 and 2: relationship to each other and to aphthoviruses and cardioviruses.equine rhinoviruses (ervs) are picornaviruses which cause a mild respiratory infection in horses. the illness resembles the common cold brought about by rhinoviruses in humans; however, the presence of a viraemia during erv-1 infection, the occurrence of persistent infections and the physical properties are all more reminiscent of foot-and-mouth disease virus (fmdv). cdna cloning and sequencing of the genomes of erv-1 and erv-2 between the poly(c) and poly(a) tracts showed that the serotypes are ...19968760418
efficient infection of cells in culture by type o foot-and-mouth disease virus requires binding to cell surface heparan sulfate.foot-and-mouth disease virus (fmdv) enters cells by attaching to cellular receptor molecules of the integrin family, one of which has been identified as the rgd-binding integrin alpha(v)beta3. here we report that, in addition to an integrin binding site, type o strains of fmdv share with natural ligands of alpha(v)beta3 (i.e., vitronectin and fibronectin) a specific affinity for heparin and that binding to the cellular form of this sulfated glycan, heparan sulfate, is required for efficient infe ...19968764038
pathogenesis of wild-type and leaderless foot-and-mouth disease virus in cattle.four calves were experimentally infected via aerosol with foot-and-mouth disease virus. two were infected with a wild-type virus derived from a full-length infectious clone (a12-ic), and two were infected with a clone-derived virus lacking the leader gene (a12-llv2), with euthanasia and tissue collection at 24 and 72 h postexposure (hpe). clinical disease was apparent only in the animal given a12-ic and euthanized at 72 hpe. in situ hybridization revealed that the animal infected with a12-ic and ...19968764079
[nucleotide sequence of the rna polymerase gene attenuated by a variant of foot-and-mouth disease virus and its comparison with the virulence of related variants of subtype a22].the nucleotide sequence of rna-polymerase gene and 3'-terminal untranslated genome region of attenuated foot-and-mouth disease virus (fmdv) strain a(22)645 has been determined. rna-polymerase gene and predicted amino acid sequences of attenuated fmdv strain a(22)645 were compared with those of the original virulent fmdv strain a(22)550. the examined genome region of strain a(22)645 differed from that of strain a(22)550 by 22 nucleotides and 3 amino acids. three mutations occurred within nucleoti ...19968786750
evolution of a persistent aphthovirus in cytolytic infections: partial reversion of phenotypic traits accompanied by genetic diversification.foot-and-mouth disease virus (fmdv) shows a dual potential to be cytolytic or to establish persistent infections in cell culture. fmdv r100, a virus rescued after 100 passages of carrier bhk-21 cells persistently infected with fmdv clone c-s8c1, showed multiple genetic and phenotypic alterations relative to the parental clone c-s8c1. several fmdv r100 populations have been subjected to 100 serial cytolytic infections in bhk-21 cells, and the reversion of phenotypic and genetic alterations has be ...19968794296
perturbations in the surface structure of a22 iraq foot-and-mouth disease virus accompanying coupled changes in host cell specificity and antigenicity.foot-and-mouth disease virus (fmdv) is an extremely infectious and antigenically diverse picornavirus of cloven-hoofed animals. strains of the a22 subtype have been reported to change antigenically when adapted to different growth conditions. to investigate the structural basis of this phenomenon we have determined the structures of two variants of an a22 virus.19968805520
long-term, large-population passage of aphthovirus can generate and amplify defective noninterfering particles deleted in the leader protease gene.during serial undiluted passage of a clonal population of foot-and-mouth disease virus (fmdv c-s8c1) in bhk-21 cells, two species of defective rna were generated and selected. sequence analysis revealed that they included deletions within the l-coding region, and retained the correct reading frame for viral protein synthesis. these deleted rnas directed the synthesis of capsid protein vp1, were packaged in particles sedimenting with standard virus, required homologous infectious helper virus in ...19968806535
identification of foot-and-mouth disease virus-free regions by use of a standardized enzyme-linked immunoelectrotransfer blot assess the potential of a highly sensitive enzyme-linked immunoelectrotransfer blot (eitb) assay to monitor persistent foot-and-mouth disease (fmd) viral activity in a livestock population.19968807005
a porcine cd8+ t cell clone with heterotypic specificity for foot-and-mouth disease virus.foot-and-mouth disease virus (fmdv)-specific t cell lines and clones have been obtained from a swine lymphocyte antigen (sla) inbred miniature pig vaccinated with chemically inactivated virus. one of the clones obtained, ce3, showed a specific and heterotypic proliferation against infectious but not inactivated fmdv in the presence of syngeneic peripheral blood mononuclear cells (pbmc). adherent cells from pbmc were sufficient to support specific activation of the clone and the proliferation was ...19968811008
preparation of virus-infection-associated (via) antigen of foot-and-mouth disease (fmd) virus from inactivated vaccine.virus-infection-associated (via) antigen of foot-and-mouth disease (fmd) virus was prepared from an inactivated fmd vaccine. the via antigen coupled with an adjuvant of aluminium hydroxide gel supplemented vaccine was efficiently eluted by suspending and stirring in high concentration of phosphate buffer solution (0.3m, ph 7.6). the final elute purified by deae-sephadex a50 from the vaccine was concentrated in 1/500-1/1,000 of the original volume. via antigens prepared from two kinds of vaccine ...19968811637
[mechanisms involved in the prolonged humoral immune response: behavior of aphthous fever virus].foot and mouth disease (fmd) is a widespread infectious disease affecting cloven-hoofed animals with severe economic consequences. animals infected with fmd virus (fmdv) develop an immunological status of immunity characterized by high titers of virus serotype-specific neutralizing antibodies (nab) which persist for at least 18 months. in contrast, currently inactivated virus vaccines elicit lower antibody response for shorter periods. protection against fmdv infection has been commonly related ...19968815460
propagation of an attenuated virus by design: engineering a novel receptor for a noninfectious foot-and-mouth disease gain entry into cells, viruses utilize a variety of different cell-surface molecules. foot-and-mouth disease virus (fmdv) binds to cell-surface integrin molecules via an arginine-glycine-aspartic acid (rgd) sequence in capsid protein vp1. binding to this particular cell-surface molecule influences fmdv tropism, and virus/receptor interactions appear to be responsible, in part, for selection of antigenic variants. to study early events of virus-cell interaction, we engineered an alternative an ...19968816817
prevalence of foot-and-mouth disease antibodies in dairy herds in the netherlands four years after vaccination.a total of 298 serum samples were collected from dutch cattle born in 1988 or before, and examined in the virus neutralisation test for antibodies against foot-and-mouth disease virus types a10 holland. o bfs, and c1detmold. all the cattle had been vaccinated at least twice during the annual vaccination programme, which stopped in 1991. antibody titres equal to or higher than the titre at which 95 per cent of the cattle would be expected to be protected against challenge, were found in 57 to 73 ...19968819202
serological and molecular analysis of serotype o foot-and-mouth disease virus isolated from disease outbreaks in india during 1987-91.foot-and-mouth disease virus (fmdv) type o outbreaks have been reported frequently in vaccinated cattle in india. twenty-five field isolates, recovered from outbreaks in vaccinated and unvaccinated cattle between 1987 and 1991, were analyzed in relation to the vaccine strain (r2/75) by complement fixation, serum neutralization and partial nucleotide sequencing of the vp1 gene. these sequences were compared with the viral sequences in genembl database. although the indian type o viruses were clos ...19968822633
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
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
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