Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| isolation of the bacteriophage dinohi from dichelobacter nodosus and its interactions with other integrated genetic elements. | the gram-negative anaerobic pathogen dichelobacter nodosus carries several genetic elements that integrate into the chromosome. these include the inta, intb, intc and intd elements, which integrate adjacent to csra and pnpa, two putative global regulators of virulence and the virulence-related locus, vrl, which integrates into ssra. treatment of d. nodosus strains with ultraviolet light resulted in the isolation of dinohi, a member of the siphoviridae and the first bacteriophage to be identified ... | 2008 | 19088904 |
| variation in fusobacterium necrophorum strains present on the hooves of footrot infected sheep, goats and cattle. | footrot is a disease of sheep, goats and cattle that causes losses in production and raises welfare issues world-wide. the disease is characterised by destruction of the hard keratin of the hoof leading to lameness, and both dichelobacter nodosus (d. nodosus) and fusobacterium necrophorum (f. necrophorum) are thought to be involved in the etiology of this disease. while a lot is known about the genetic diversity of d. nodosus, very little is known about variation in f. necrophorum, especially as ... | 2009 | 19019570 |
| proteomic profiling of ovine serum by seldi-tof ms: optimisation, reproducibility and feasibility of biomarker discovery using routinely collected samples. | the diagnosis of infectious diseases in animals may be enhanced by study of the serum proteome in which myriad components are influenced by physiological and pathological processes. surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry (seldi-tof ms) has the capacity to detect known and unknown immunologically relevant molecules in the serum proteome. optimum combinations of proteinchip array surfaces, energy absorbing molecules, sample dilutions and instrument settings w ... | 2010 | 18775566 |
| pilot trials in australia on eradication of footrot by flock specific vaccination. | footrot is a contagious disease of ruminants requiring strains of dichelobacter nodosus that possess virulence factors including proteases and fimbriae. sheep can be immunised against footrot using vaccine-containing fimbriae, either native or recombinant. the fimbriae are responsible for the serological k-agglutination reaction, which has been used to classify field isolates into nine major serogroups. the range of protection conferred by vaccination is largely restricted to the serogroup invol ... | 2008 | 18621488 |
| breeding for resistance to footrot--the use of hoof lesion scoring to quantify footrot in sheep. | so that genetic studies can be undertaken on footrot in sheep, it is necessary that a reliable and repeatable method to categorise the phenotype is available. this paper summarises the methods used and results obtained from 1600 hoof lesion scores of 100 mixed-age ewes independently scored twice by two trained operators. using a 5-pont scale describing the severity of foot lesions, residual correlations were used to assess agreement between scorers and scoring occasions. data were analysed using ... | 2008 | 18478350 |
| the complete sequence and functional analysis of panl, the large plasmid of the unicellular freshwater cyanobacterium synechococcus elongatus pcc 7942. | two endogenous plasmids are present in synechococcus elongatus pcc 7942, a model organism for studying photosynthesis and circadian rhythms in cyanobacteria. the large plasmid, panl, was shown previously to be involved in adaptation of s. elongatus cells to sulfur starvation, which provided the first evidence of cellular function of a cyanobacterial plasmid. here, we report the complete sequence of panl, which is 46,366 bp in length with 53% gc content and encodes 58 putative orfs. the panl plas ... | 2008 | 18353436 |
| twitching motility is essential for virulence in dichelobacter nodosus. | type iv fimbriae are essential virulence factors of dichelobacter nodosus, the principal causative agent of ovine foot rot. the fima fimbrial subunit gene is required for virulence, but fima mutants exhibit several phenotypic changes and it is not certain if the effects on virulence result from the loss of type iv fimbria-mediated twitching motility, cell adherence, or reduced protease secretion. we showed that mutation of either the pilt or pilu gene eliminated the ability to carry out twitchin ... | 2008 | 18310333 |
| analyses of the vrl gene cluster in desulfococcus multivorans: homologous to the virulence-associated locus of the ovine footrot pathogen dichelobacter nodosus strain a198. | major parts of the virulence-associated vrl locus known from the gammaproteobacterium dichelobacter nodosus, the causative agent of ovine footrot, were analyzed in the genome of the sulfate-reducing deltaproteobacterium desulfococcus multivorans. in the genome of d. multivorans 13 of the 19 vrl genes described for d. nodosus are present and highly conserved with respect to gene sequence and order. the vrl locus and its flanking regions suggest a bacteriophage-mediated transfer into the genome of ... | 2007 | 17693723 |
| glycosylation of type-iv fimbriae of dichelobacter nodosus. | dichelobacter nodosus is the causative agent of ovine footrot and the type-iv fimbriae on this bacterium are essential for maintaining its virulence. in this study, we reveal that these fimbriae are glycosylated. this was demonstrated in several ways: by the detection of carbohydrate on fimbrial protein using periodic acid schiff reagent (pas) staining of sds-page gels and by demonstrating enzymatic deglycosylation and by analysis of the amino acid sequences derived from the fima gene, whereby t ... | 2008 | 17681435 |
| type iv fimbrial biogenesis is required for protease secretion and natural transformation in dichelobacter nodosus. | the objective of this study was to develop an understanding of the molecular mechanisms by which type iv fimbrial biogenesis, natural transformation, and protease secretion are linked in the ovine foot rot pathogen, dichelobacter nodosus. we have shown that like the d. nodosus fimbrial subunit fima, the pilin-like protein pile and the fimn, fimo, and fimp proteins, which are homologs of pilb, pilc, and pild from pseudomonas aeruginosa, are essential for fimbrial biogenesis and natural transforma ... | 2007 | 17513472 |
| genome sequence and identification of candidate vaccine antigens from the animal pathogen dichelobacter nodosus. | dichelobacter nodosus causes ovine footrot, a disease that leads to severe economic losses in the wool and meat industries. we sequenced its 1.4-mb genome, the smallest known genome of an anaerobe. it differs markedly from small genomes of intracellular bacteria, retaining greater biosynthetic capabilities and lacking any evidence of extensive ongoing genome reduction. comparative genomic microarray studies and bioinformatic analysis suggested that, despite its small size, almost 20% of the geno ... | 2007 | 17468768 |
| assessment of current knowledge of footrot in sheep with particular reference to dichelobacter nodosus and implications for elimination or control strategies for sheep in great britain. | a brief summary of the currently accepted aetiology and pathogenesis of footrot and interdigital dermatitis in sheep in great britain is presented together with a description of the transmission dynamics of dichelobacter nodosus. approaches that may be successful for control or elimination of the disease are proposed and areas of uncertainty in current knowledge highlighted. research and practice in great britain is compared with that from other countries and the proposal made that the environme ... | 2008 | 17418598 |
| in vitro antimicrobial susceptibility of anaerobic bacteria isolated from caprine footrot. | the in vitro antimicrobial susceptibility of gram-negative anaerobic bacilli commonly isolated from footrot in goats was studied. a total of 97 isolates belonging to the genera dichelobacter, fusobacterium, prevotella, porphyromonas and bacteroides, obtained from clinical cases of footrot in south-western spain between march 2000 and may 2001, were tested against 25 antimicrobial agents comprising beta-lactams, aminoglycosides, macrolides, chloramphenicol, quinolones, lincosamides, sulphonamides ... | 2007 | 17385552 |
| detection of dichelobacter nodosus in wild ungulates (capra ibex ibex and ovis aries musimon) and domestic sheep suffering from foot rot using a two-step polymerase chain reaction. | severe keratinous hoof afflictions have been recorded in ibex (capra ibex ibex) since 1995 and more recently in mouflon (ovis aries musimon) in switzerland. based on clinical observations and comparison with diseases known to affect domestic ungulates, it was hypothesized these wild ungulates were affected by foot rot associated with infection with dichelobacter nodosus. dichelobacter nodosus has been shown to be the essential pathogen for initiation and establishment of foot rot, a highly conta ... | 2007 | 17347396 |
| isolation and characterization of dichelobacter nodosus from ovine and caprine footrot in kashmir, india. | footrot is a highly contagious and economically important disease of sheep and goats, caused by dichelobacter nodosus, a slow growing anaerobic gram-negative rod. the current australian antigenic classification system, based on variation in the fimbriae, classifies d. nodosus into at least 10 serogroups (a-i and m) and 18 serotypes. this investigation was intended to determine the serological diversity of d. nodosus in this region of kashmir, india. exudates of footrot lesions were collected fro ... | 2007 | 17250860 |
| aetiology of caprine footrot in extremadura region, spain. | the present study reports on the location of major foci of footrot in goats in the extremadura region of spain by the determination of locally occurring strictly anaerobic microorganisms involved in the pathogenesis and development of this disease. the most commonly isolated microorganisms belonged to the genera dichelobacter, fusobacterium, porphyromonas and prevotella; these were found in conjunction with other species of minor importance. the species most frequently isolated were fusobacteriu ... | 2006 | 17020135 |
| activity and cellular localization of amylases of rabbit cecal bacteria. | five 11-week-old rabbits, fed a commercial granulated feed, were slaughtered and cecal starch-degrading bacteria enumerated; total concentration of cultivable bacteria utilizing starch averaged 5.5 x 10(10) cfu/g. the activity and cellular localization of amylases was determined in 9 bacteria identified as actinomyces israeli (strains aa2 and ad4), bacteroides spp. (strain aa3), dichelobacter nodosus (strain aa4), mitsuokella multiacidus (strain aa6), eubacterium spp. (strains aa7 and ab2), clos ... | 2006 | 17007433 |
| regulation of type iv fimbrial biogenesis in dichelobacter nodosus. | type iv fimbriae are expressed by several bacterial pathogens and are essential for virulence in dichelobacter nodosus, which causes ovine footrot. we have identified a two-component signal transduction system (pilr/s) and an alternative sigma factor (sigma 54) that were shown by insertional inactivation to be required for the regulation of fimbrial biogenesis in d. nodosus. western blots showed that in both pilr and rpon mutants, fimbrial subunit production was significantly reduced by a proces ... | 2006 | 16788189 |
| improved diagnosis of virulent ovine footrot using the inta gene. | footrot is a mixed bacterial infection of the hooves of sheep. the gram-negative anaerobic bacterium dichelobacter nodosus is the principal causative agent, with different strains causing diseases of different severity, ranging from benign to virulent. in australia, in the state of new south wales (nsw), only virulent footrot is subject to regulatory action, including quarantine. however, it is often difficult to distinguish benign footrot from virulent footrot in the initial stages of infection ... | 2006 | 16716540 |
| current understanding of the aetiology and laboratory diagnosis of footrot. | footrot is a highly contagious disease of the feet of ruminants caused by the synergistic action of certain bacterial species of which dichelobacter nodosus (d. nodosus) is the main transmitting agent. the infection is specific to sheep and goats, although it has also been reported in cattle, horses, pigs, deer and mouflon. the antigenic diversity of d. nodosus is due to variations in the dna sequence of its fimbrial subunit gene (fima) and provides the basis for classification of the organism i ... | 2006 | 16624707 |
| distribution and prevalence of footrot in bhutan. | the first cases of footrot in bhutan were reported in sheep in 1990 at the national sheep breeding centre (nsbc), which supplies breeding animals to village sheep flocks throughout bhutan. despite the presence of footrot at the centre the distribution of apparently disease-free sheep continued. cases of footrot were reported in village flocks soon after the disease was diagnosed at nsbc. a national survey was designed to establish the distribution and prevalence of footrot in bhutan. this detect ... | 2006 | 16490719 |
| recent footrot outbreak in debrezeit swine farm, central ethiopia. | an outbreak of footrot has occurred in debrezeit swine farm that is located 44 km south east of the capital. among 24 pigs, 75% showed lameness, hot, painful and swollen feet, hemorrhagic bruising of the coronary band, heel erosion, sole ulcers and separation of skin from hoof on hind limbs. bacteriological examination of the specimen from the affected limbs has shown the involvement of staphylococcus, streptococcus and dichelobacter nodosus. the overt clinical lameness and inability to stand or ... | 2005 | 16294005 |
| the occurrence of treponemes in contagious ovine digital dermatitis and the characterisation of associated dichelobacter nodosus. | contagious ovine digital dermatitis (codd) is a recently recorded, apparently new infection of the ovine hoof, which differs clinically from footrot caused by dichelobacter nodosus and which fails to respond well to accepted treatment practices for footrot. despite the welfare implications of such an infection, very little research has been performed on codd to date and the aetiology remains confused. suggestions have been made that there is a potential role for treponemes in the pathogenesis of ... | 2005 | 16280206 |
| update on ovine footrot in new zealand: isolation, identification, and characterization of dichelobacter nodosus strains [corrected]. | dichelobacter nodosus, a gram-negative strict anaerobe, is the essential causative agent of ovine footrot. despite its worldwide presence, the disease has significant economic impact in those sheep-farming countries with a temperate climate and moderate to high rainfall, such as new zealand (nz) and australia. in this study, we aimed to isolate, identify, and characterize as many d. nodosus strains as possible from nz farms by using polymerase chain reaction (pcr)-based technology. understanding ... | 2005 | 16280202 |
| the use of melatonin as a vaccine agent. | molecules with immunomodulatory properties determine the magnitude and quality of immune responses specific for the coadministered antigen. melatonin is considered a biological-response modifier of the immune system with broad application in veterinary medicine. in seasonally-breeding animals, the indolamine is able to improve reproductive performance. with the purpose of expanding new advantageous roles for melatonin, we investigated the effect of subcutaneous slow-release melatonin implants in ... | 2005 | 16055232 |
| the use of an autogenous dichelobacter nodosus vaccine to eliminate clinical signs of virulent footrot in a sheep flock in bhutan. | an outbreak of virulent footrot was investigated in a flock of 605 merino cross-bred sheep in bhutan. conventional control methods in the preceding eight years had reduced its prevalence from 36-79% in different components of the flock to about 15% overall. only one serogroup (b) of dichelobacter nodosus was identified among 40 isolates cultured from affected sheep. a vaccine prepared from this strain was used in a pilot trial to compare the response of 14 treated and 14 untreated sheep. all aff ... | 2006 | 16019243 |
| the detection and characterisation of dichelobacter nodosus from cases of ovine footrot in england and wales. | footrot, caused by the strictly anaerobic bacterium dichelobacter nodosus, is the most common cause of lameness in sheep in great britain but problems exist in association with its diagnosis and control. the fastidious nature of d. nodosus means that complex media and several weeks are required for characterisation. an alternative method to simplify and enhance the detection of d. nodosus in clinical samples is therefore highly desirable. in terms of control, anecdotal evidence from the farming ... | 2005 | 15917134 |
| plasmid-borne florfenicol resistance in pasteurella multocida. | a florfenicol-resistant pasteurella multocida isolate from a calf was investigated for the genetic basis of florfenicol resistance and the location of the resistance gene. | 2005 | 15814600 |
| current approaches to the management of ovine footrot. | ovine footrot remains the most important cause of lameness in sheep flocks in the uk, despite the existence of proven methods for the control of the disease. recent research suggests that sheep farmers may be unaware of these methods and may allocate greater resources to treatment of footrot rather than to its prevention. foot paring, topical treatments, vaccination and parenteral antibiotic therapy all have a role in treating sheep with advanced footrot infections, but prevention of severe infe ... | 2005 | 15683762 |
| comparative study of three surgical treatments for two forms of the clinical presentation of bovine pododermatitis. | in this study, 1013 animals showing signs of clinical pododermatitis were examined and divided into five unevenly numbered groups. affected animals in groups i and ii showed only signs of vegetative interdigital pododermatitis. the lesions were surgically removed and either protected with bandages (in group i) or cauterized with incandescent iron (group ii). the animals in groups iii, iv, and v, showed signs of necrotic pododermatitis. these were treated with different protocols after the necrot ... | 2004 | 15604479 |
| identification of a dichelobacter nodosus ferric uptake regulator and determination of its regulatory targets. | the expression of iron regulated genes in bacteria is typically controlled by the ferric uptake regulator (fur) protein, a global transcriptional repressor that regulates functions as diverse as iron acquisition, oxidative stress, and virulence. we have identified a fur homologue in dichelobacter nodosus, the causative agent of ovine footrot, and shown that it complements an escherichia coli fur mutant. homology modeling of the d. nodosus fur protein with the recently solved crystal structure of ... | 2005 | 15601721 |
| effectiveness of different adjuvants in stimulating dichelobacter nodosus antibody in sheep vaccinated against ovine footrot. | this research consists of an evaluation of the effectiveness of different substances administered as adjuvants in the stimulation of humoral immune response induced by the vaccine composed of strains a1, a2 and c of dichelobacter nodosus. to do this, a total of 120 merino sheep were vaccinated and revaccinated. these sheep were selected from a farm located in the region of extremadura (spain), and they were divided into 12 groups of 10 animals each. an additional group with 10 sheep was used as ... | 2004 | 15379443 |
| comparative study of biochemical methods for the identification of dichelobacter nodosus. | the aim of this study was to compare four identification procedures to detect dichelobacter nodosus and develop a rapid, simple and effective method to identify d. nodosus strains isolated from cases of ovine footrot. the four methods used were: (a) the classic guidelines set down by holdeman et al. (1977) and summanen et al. (1993) which are based on gas liquid chromatography (glc) and different biochemical tests, this method was considered as landmark; (b) baron and citron's flowchart for the ... | 2004 | 15379442 |
| minimum inhibitory concentrations for 25 selected antimicrobial agents against dichelobacter nodosus and fusobacterium strains isolated from footrot in sheep of portugal and spain. | the agar dilution method was used to determine the inhibitory activity of 25 antimicrobial agents against 69 strains of dichelobacter nodosus and 108 strains of the genus fusobacterium, all of which were isolated from 90 clinical cases of ovine footrot between october 1998 and november 2000. in the case of the micro-organisms belonging to the genus fusobacterium, the six beta-lactams studied (benzyl penicillin, ampicillin, cloxacillin, cefadroxil, cefuroxime and cephalexine) proved to be, in gen ... | 2004 | 15330985 |
| molecular detection and characterization of dichelobacter nodosus in ovine footrot in india. | dichelobacter nodosus was detected in three clinical cases of ovine footrot in kashmir, india. the detection was done by pcr in three clinical specimens directly, without isolating the organism, using species-specific 16s rdna primers. positive results were indicated by amplification of a 783 bp product. all the three samples were subjected to serogrouping by multiplex pcr using group (a-i) specific primers. all the three samples revealed the presence of serogroup b of d. nodosus by yielding a s ... | 2004 | 15294315 |
| eradication of footrot of lesser clinical severity (intermediate footrot). | to determine if intermediate footrot (ifr) can be eradicated from a flock of sheep by inspection and culling of cases during a non-transmission period and if prior antibiotic treatment or vaccination increases the likelihood of eradication. | 2003 | 15086111 |
| failure to eradicate ovine footrot associated with dichelobacter nodosus strain a198 by repeated daily footbathing in zinc sulphate with surfactant. | to investigate the effect of repeated daily footbathing in zinc sulphate on virulent ovine footrot associated with s1, u1 and u5 zymogram types of dichelobacter nodosus, including the highly virulent s1 strain a198. | 2003 | 15084013 |
| genome sequences of two closely related vibrio parahaemolyticus phages, vp16t and vp16c. | two bacteriophages of an environmental isolate of vibrio parahaemolyticus were isolated and sequenced. the vp16t and vp16c phages were separated from a mixed lysate based on plaque morphology and exhibit 73 to 88% sequence identity over about 80% of their genomes. only about 25% of their predicted open reading frames are similar to genes with known functions in the genbank database. both phages have cos sites and open reading frames encoding proteins closely related to coliphage lambda's termina ... | 2003 | 14563879 |
| contagious ovine digital dermatitis. | 2003 | 12790246 | |
| clinical and radiographic findings in six cattle with cervical diskospondylitis. | 2003 | 12790169 | |
| ovine periodontitis as a potential model for periodontal studies. cross-sectional analysis of clinical, microbiological, and serum immunological parameters. | : to investigate infection and host immunity patterns in sheep with naturally occurring "broken-mouth" periodontitis. | 2003 | 12702113 |
| aetiology of ovine footrot in the portuguese region of alto alentejo. | in this work, we found it appropriate to carry out a study directed towards isolating and identifying the entailed microorganisms which trigger off footrot in sheep, placing special emphasis on the serotipification of the different dichelobacter nodosus species. with this goal in mind four flocks from the portuguese region of 'alto alentejo' were selected, all of them had one common feature: their main health problem was ovine footrot. we also set out to determine the elastolitic capacity of iso ... | 2003 | 12667188 |
| transformation-mediated serogroup conversion of dichelobacter nodosus. | dichelobacter nodosus is the essential causative agent of footrot in sheep. the type iv fimbriae of d. nodosus are required for virulence, are highly immunogenic and immunoprotective, and can be divided into 10 major serogroups. fimbrial variation has been postulated to have arisen because of genetic recombination within the fimbrial gene region perhaps as a means of evading the immune response invoked by infection. to show that antigenic variation in these fimbriae could occur after natural tra ... | 2003 | 12488080 |
| serogroup specific single and multiplex pcr with pre-enrichment culture and immuno-magnetic bead capture for identifying strains of d. nodosus in sheep with footrot prior to vaccination. | the identification of dichelobacter nodosus present in a flock is a prerequisite to specific (autogenous) vaccination. current methods of identification of the serogroup present in a population requires that the organisms be isolated, identified visually in mixed culture on streak plates, subcultured to purify and subjected to antigenic analysis. this process takes at least 3 to 4 weeks. this study describes the development of a simple and rapid serogroup specific pcr test for d. nodosus. a comm ... | 2002 | 12270270 |
| eradication of virulent footrot from sheep and goats in an endemic area of nepal and an evaluation of specific vaccination. | programmes based on the identification and treatment of cases and the culling of animals refractory to treatment had failed to eradicate virulent footrot from two districts in the western region of nepal. from 1993 to 1996 vaccination against two endemic virulent strains of dichelobacter nodosus was tested for its potential to contribute to the eradication of footrot from the region. only sheep and goats which had been free of signs of footrot at three inspections at monthly intervals before the ... | 2002 | 12243270 |
| diagnosis of footrot in goats: application of elisa tests for response to antigens of dichelobacter nodosus. | goats are an important natural host for footrot and are infected with dichelobacter nodosus that have virulence characteristics similar to those of sheep strains. however, the humoral response of goats to d. nodosus antigens and the possibility of a serological diagnosis of footrot in goats have not been studied. with the aim of evaluating a diagnostic elisa test, we investigated the primary immune response of goats to experimental and natural infection, the memory response in recovered animals, ... | 2002 | 12052334 |
| characterization and expression of a novel porphyromonas gingivalis outer membrane protein, omp28. | we report the characterization of a porphyromonas gingivalis gene, designated omp28, encoding a protein that we have previously purified and characterized as a 28-kda outer membrane protein. the deduced amino acid sequence of the omp28 open reading frame displayed an outer membrane leader sequence and lipoprotein attachment site but did not exhibit any significant overall sequence identity with protein sequences in the databases. a small stretch of amino acids (19 residues) exhibits 50% sequence ... | 2002 | 12030966 |
| genomic islands of dichelobacter nodosus. | 2002 | 12012869 | |
| evaluation of equine immunoglobulin specific for rhodococcus equi virulence-associated proteins a and c for use in protecting foals against rhodococcus equi-induced pneumonia. | to determine whether purified equine immunoglobulin specific for rhodococcus equi virulence-associated proteins a and c (vapa and vapc) can confer passive protection against r. equi-induced pneumonia in foals. | 2001 | 11497456 |
| eradication of ovine footrot by repeated daily footbathing in a solution of zinc sulphate with surfactant. | to investigate the effect on ovine footrot of repeated daily footbathing in a solution of zinc sulphate with surfactant. | 2001 | 11491224 |
| the type iv fimbrial subunit gene (fima) of dichelobacter nodosus is essential for virulence, protease secretion, and natural competence. | dichelobacter nodosus is the essential causative agent of footrot in sheep. the major d. nodosus-encoded virulence factors that have been implicated in the disease are type iv fimbriae and extracellular proteases. to examine the role of the fimbriae in virulence, allelic exchange was used to insertionally inactivate the fima gene, which encodes the fimbrial subunit protein, from the virulent type g d. nodosus strain vcs1703a. detailed analysis of two independently derived fima mutants revealed t ... | 2001 | 11443078 |
| comparison of erythromycin and oxytetracycline for the treatment of ovine footrot. | a microbiological study of 25 cases of ovine footrot was performed. cultures belonging to dichelobacter nodosus were isolated in 48% of the sampled animals. the sensitivity of the 99 strict anaerobic bacterial isolates to 5 antibiotics (penicillin g, amoxycillin, spiramycin, erythromycin and oxytetracycline) was studied. the percentage of resistant cultures was in all cases higher than 30%. the efficacy of erythromycin and oxytetracycline in the treatment of ovine footrot was studied. to conduct ... | 2001 | 11402641 |
| rapid and accurate typing of dichelobacter nodosus using pcr amplification and reverse dot-blot hybridisation. | here we describe an approach to genotyping d. nodosus, based on variation in the fimbrial subunit gene (fima), which uses polymerase chain reaction (pcr) amplification and hybridisation to immobilised oligonucleotides (pcr/oligotyping). the variable region of d. nodosus fima, amplified and labelled with digoxigenin (dig) in a single multiplex pcr amplification, was hybridised to a panel of group- and type-specific poly-dt tailed oligonucleotides that were immobilised on a nylon membrane strip. a ... | 2001 | 11295335 |
| dichelobacter nodosus serotype m fimbrial subunit gene: implications for serological classification. | dichelobacter nodosus fimbrial subunit gene (fima) from a serotype m strain (m-spahl) was investigated in this study. a primer set targeting the relatively conserved fima regions and based on the published sequence from nepalese serogroup m isolates (nepalese m), failed to amplify the fima of m-spahl. however, when the downstream primer was substituted with a primer that is specific for other serogroups of d. nodosus, the fima was successfully amplified. cloning followed by dna sequencing, revea ... | 2001 | 11267795 |
| pseudomonas stutzeri has two closely related pila genes (type iv pilus structural protein) with opposite influences on natural genetic transformation. | pseudomonas stutzeri has type iv pili for which the pila gene (here termed pilai) provides the structural protein and which are required for dna uptake and natural genetic transformation. downstream of pilai we identified a gene, termed pilaii, coding for a deduced protein with a size similar to that of pilai with 55% amino acid sequence identity and with a typical leader peptide including a leader peptidase cleavage site. fusions to lacz revealed that pilaii is expressed only about 10% compared ... | 2001 | 11244078 |
| pilus elisa and an anamnestic test for the diagnosis of virulent ovine footrot and its application in a disease control program in nepal. | the immunological memory (anamnestic) responses in sheep recovered from virulent footrot (vfr) can be aroused by subcutaneous injection of outer membrane protein (omp) antigens of dichelobacter nodosus. the magnitude of this response is directly correlated to the highest antibody response attained during infection and memory lasts at least a year after recovery from vfr. however, some older animals show non-specific responses to omp antigens. in this study an evaluation of d. nodosus pilus antig ... | 2001 | 11230927 |
| vaccination against ovine footrot using a live bacterial vector to deliver basic protease antigen. | a strain of corynebacterium pseudotuberculosis, designated toxminus, that has been rationally attenuated by deletion of the phospholipase d gene, is being developed as a live vaccine vector for the delivery of veterinary vaccine antigens. in the present study a recombinant form of the basic protease gene of the ovine footrot causative bacterium, dichelobacter nodosus, was introduced into the vector strain using the high copy number plasmid pep2. this strain secreted the basic protease protein. v ... | 2001 | 11164307 |
| 3'overhangs influence pcr-sscp patterns. | 2000 | 11084854 | |
| novel fimbrial subunit genes of dichelobacter nodosus: recombination in vivo or in vitro? | polymerase chain reaction (pcr) was used to amplify the variable region of the fimbrial subunit encoding gene (fima) of dichelobacter nodosus from sheep and goats infected with footrot. two amplimers (designated x and y) generated single-strand conformation polymorphism (sscp) patterns different to those of previously identified serogroups and serotypes. dna sequencing revealed that these two fragments were novel. the upstream of x (nt 1-183) was identical to serotype m1 while its downstream (nt ... | 2000 | 10946146 |
| occurrence of different strains of dichelobacter nodosus in new clinical lesions in sheep exposed to footrot associated with multi-strain infections. | to investigate the occurrence of s1, u1 and t strains of dichelobacter nodosus in new clinical lesions in sheep exposed to footrot associated with multi-strain infections. | 2000 | 10840576 |
| identification and characterization of a native dichelobacter nodosus plasmid, pdn1. | the gram-negative anaerobe dichelobacter nodosus is the primary causative agent of ovine footrot, a mixed bacterial infection of the hoof. we report here the characterization of a novel native plasmid, pdn1, from d. nodosus. sequence analysis has revealed that pdn1 has a high degree of similarity to broad-host-range plasmids belonging, or related, to escherichia coli incompatibility group q. however, in contrast to these plasmids, pdn1 encodes no antibiotic resistance determinants, lacks genes e ... | 2000 | 10783302 |
| type iv pilus genes pila and pilc of pseudomonas stutzeri are required for natural genetic transformation, and pila can be replaced by corresponding genes from nontransformable species. | pseudomonas stutzeri lives in terrestrial and aquatic habitats and is capable of natural genetic transformation. after transposon mutagenesis, transformation-deficient mutants were isolated from a p. stutzeri jm300 strain. in one of them a gene which coded for a protein with 75% amino acid sequence identity to pilc of pseudomonas aeruginosa, an accessory protein for type iv pilus biogenesis, was inactivated. the presence of type iv pili was demonstrated by susceptibility to the type iv pilus-dep ... | 2000 | 10735861 |
| extensive diversity in new zealand dichelobacter nodosus strains from infected sheep and goats. | footrot is a contagious bacterial disease of ruminants spread by the gram-negative, anaerobic organism, dichelobacter nodosus. it is endemic in new zealand and throughout sheep and goat farming regions of the world. using the polymerase chain reaction (pcr) to amplify fragments of the fimbrial gene (fima), d. nodosus was detected in 14 hoof scrapings, sampled from six farming regions within new zealand. dna sequencing revealed 15 strains covering eight serogroups on the new zealand farms. the pr ... | 2000 | 10665539 |
| severe ovine foot disease. | 1999 | 10619613 | |
| genetic characterisation of protective vaccine responses in sheep using multi-valent dichelobacter nodosus vaccines. | protective vaccine responses to nine distinct serogroups of dichelobacter nodosus (serogroups a-i) can be readily measured by serogroup-specific k-agglutinating antibody titres. on the basis of a large quantitative genetic experiment (1200 progeny from 129 sire groups), it was shown that variation in antibody responses following vaccination with a multi-valent pilus antigen d. nodosus vaccine (serogroups a-i) is, in part, under genetic control and thus heritable. based on the genetic relationshi ... | 1999 | 10614512 |
| the site-specific integration of genetic elements may modulate thermostable protease production, a virulence factor in dichelobacter nodosus, the causative agent of ovine footrot. | the gram-negative anaerobe dichelobacter nodosus is the causative agent of footrot in sheep. the authors have previously characterized two genetic elements, the inta (vap) and intb elements, which integrate into the genome of d. nodosus. in the virulent strain a198 there are two copies of the inta element. one copy is integrated into the 3' end of the trna-sergcu gene, close to the aspartokinase (aska) gene, and the second copy is integrated into the 3' end of the trna-sergga gene, next to the p ... | 1999 | 10537206 |
| identification of a virulence-associated protein homolog gene and isra1 in a plasmid of riemerella anatipestifer. | riemerella anatipestifer is the causative agent of polyserositis of ducks and geese. we have previously reported that a 3.9-kb plasmid, pcfc1, carries protein genes (vapd1 and vapd2) that are similar to virulence-associated genes of other bacteria. in the present study, we report the complete sequence of a second plasmid of 5.6 kb, pcfc2. pcfc2 has a 28% g-c content and three large open reading frames (orfs). one of the orfs (designated asvapd1) encodes a polypeptide that shares 53.9, 53.9, 48.3 ... | 1999 | 10481080 |
| pcr-rflp of outer membrane proteins gene of dichelobacter nodosus: a new tool in the epidemiology of footrot. | currently only phenotypic epidemiological markers, serogrouping and virulence testing of dichelobacter nodosus, are available for investigating footrot outbreaks in small ruminants. these methods have limitations in tracing the source of infection. in this study, a genotypic marker, pcr-rflp of outer membrane protein gene, was used to characterize d. nodosus. the technique was evaluated in a controlled experiment involving two strains of bacteria. pcr-rflp was found to be highly specific in diff ... | 1999 | 10459657 |
| transmission of virulent footrot between sheep and goats. | to determine the infectivity of ovine and caprine strains of dichelobacter nodosus for both sheep and goats. | 1999 | 10451731 |
| eikenella corrodens phase variation involves a posttranslational event in pilus formation. | the human pathogen eikenella corrodens synthesizes type iv pili and exhibits a phase variation involving the irreversible transition from piliated to nonpiliated variants. on solid medium, piliated variants form small (s-phase), corroding colonies whereas nonpiliated variants form large (l-phase), noncorroding colonies. we are studying the molecular basis of this phase variation in the clinical isolate e. corrodens va1. a genomic fragment encoding the major type iv pilin was cloned from the s-ph ... | 1999 | 10400570 |
| effectiveness of small workshops for improving farmers' knowledge about ovine footrot. | to determine sheep farmers' attitudes to and beliefs about ovine footrot, and to improve their knowledge about the diagnosis, control and eradication of this disease. | 1999 | 10376104 |
| a bacteriophage encoding a pathogenicity island, a type-iv pilus and a phage receptor in cholera bacteria. | the virulence properties of many pathogenic bacteria are due to proteins encoded by large gene clusters called pathogenicity islands, which are found in a variety of human pathogens including escherichia coli, salmonella, shigella, yersinia, helicobacter pylori, vibrio cholerae, and animal and plant pathogens such as dichelobacter nodosus and pseudomonas syringae. although the presence of pathogenicity islands is a prerequisite for many bacterial diseases, little is known about their origins or ... | 1999 | 10360577 |
| update on footrot in south-west germany. | 82 dichelobacter nodosus strains isolated from 9 footrot affected sheep flocks in south west germany were serotyped and tested for virulence. serovar b was present in all flocks, representing 64.4% of all isolated d. nodosus field strains. other serovares found were type a, c, e, g and h. virulent strains were identified in 5 flocks, while intermediate strains were isolated from all 9 flocks. all serological untypeable strains proved to be avirulent. based on these epidemiological findings the u ... | 1999 | 10085580 |
| complete nucleotide sequence of the 27-kilobase virulence related locus (vrl) of dichelobacter nodosus: evidence for extrachromosomal origin. | the vrl locus is preferentially associated with virulent isolates of the ovine footrot pathogen, dichelobacter nodosus. the complete nucleotide sequence of this 27.1-kb region has now been determined. the data reveal that the locus has a g+c content much higher than the rest of the d. nodosus chromosome and contains 22 open reading frames (orfs) encoding products including a putative adenine-specific methylase, two potential deah atp-dependent helicases, and two products with sequence similarity ... | 1999 | 10024571 |
| identification and grouping of dichelobacter nodosus, using pcr and sequence analysis. | dichelobacter nodosus is the causative agent of ovine foot rot, a disease that is a constant economic burden for many western sheep ranches. vaccination is one method of treating foot rot. a higher and more specific immune response is observed when monovalent vaccines are used to treat foot rot, as compared to multivalent vaccines, which incorporate all 10 major new zealand d. nodosus serogroups. there is no single assay for specifically identifying and grouping d. nodosus for the purpose of inc ... | 1999 | 10024434 |
| isolation of spirochaetes from an incident of severe virulent ovine footrot. | 1998 | 9921625 | |
| electroporation-mediated transformation of the ovine footrot pathogen dichelobacter nodosus. | studies on the potential virulence genes of the ovine footrot pathogen dichelobacter nodosus have been hindered by the lack of a genetic system for this organism. in an attempt to accomplish the transformation of d. nodosus cells, we constructed a plasmid that contained part of a native d. nodosus plasmid and carried a tetracycline resistance gene that was located between the d. nodosus rrna promoter and terminator. this plasmid was used to transform several d. nodosus strains to tetracycline re ... | 1998 | 9868785 |
| molecular analysis of dichelobacter nodosus isolated from footrot in sheep in malaysia. | pulsed field gel electrophoresis analysis of genomic dna was used to investigate genetic diversity among dichelobacter nodosus from footrot in sheep in malaysia. twelve dichelobacter nodosus strains isolated from lesion materials from infected sheep were confirmed as dichelobacter nodosus by polymerase chain reaction technique using the species-specific dichelobacter nodosus 16s rna sequence ac and c as primers. pulsed field gel electrophoresis banding profiles using restriction enzymes apai (5' ... | 1998 | 9791871 |
| identification and characterisation of serogroup m among nepalese isolates of dichelobacter nodosus, the transmitting agent of footrot in small ruminants. | one thousand and sixty three isolates of dichelobacter nodosus cultured between 1992 and 1996 from cases of footrot in sheep and goats of migratory flocks of nepal were characterised by agglutination test using prototype antisera of the australian classification system. of those, sixty six isolates could not be classified into any of the nine serogroups (a-i). this study was therefore undertaken to characterise these isolates. it was established that they were agglutinated by antiserum against s ... | 1998 | 9791869 |
| the gene for toxic shock toxin is carried by a family of mobile pathogenicity islands in staphylococcus aureus. | tst, the gene for toxic shock syndrome toxin-1 (tsst-1), is part of a 15.2 kb genetic element in staphylococcus aureus that is absent in tsst-1-negative strains. the prototype, in rn4282, is flanked by a 17 nucleotide direct repeat and contains genes for a second possible superantigen toxin, a dichelobacter nodosus vape homologue and a putative integrase. it is readily transferred to a reca recipient, and it always inserts into a unique chromosomal copy of the 17 nucleotide sequence in the same ... | 1998 | 9720870 |
| biodegradable implants for the delivery of veterinary vaccines: design, manufacture and antibody responses in sheep. | biodegradable implants made from cholesterol and lecithin (c:l) were used to deliver a recombinant antigen (recombinant dichelobacter nodosus pili) and adjuvant (quil a) to sheep. implants (5.5- x 1.8-mm) were placed subcutaneously and compared to a conventional vaccination regime (2 injections, 4 weeks apart) for antibody responses and tissue compatibility. release profiles of antigen and adjuvant were also studied in vitro and in vivo. the presence of quil a in vaccine implants had a marked ef ... | 1998 | 9685925 |
| purification and characterization of a putative fimbrial protein/receptor of porphyromonas gingivalis. | porphyromonas gingivalis has been implicated as a major aetiological agent in certain forms of periodontal disease, p. gingivalis is a gram-negative, asaccharolytic bacterium that obtains energy from the fermentation of amino acids derived from the hydrolysis of host protein. virulence factors of this bacterium include the capsule, fimbrial adhesins, cytotoxins and extracellular hydrolytic enzymes. a 43 kda fimbrillin from p. gingivalis has been isolated and characterized. however, there is evid ... | 1998 | 9612983 |
| severity and persistence of footrot in merino sheep experimentally infected with a protease thermostable strain of dichelobacter nodosus at five sites. | to test the hypothesis that ovine footrot associated with a thermostable protease strain of dichelobacter nodosus undergoes self cure or is sustained as an annually recurring disease, depending on the environment. | 1998 | 9578765 |
| aetiology of ovine footrot in spain. | four hundred and sixty strains of obligate anaerobes were isolated from 216 cases of ovine foot rot distributed throughout spain. the predominant species was dichelobacter nodosus, which was isolated in 168 cases (77.8 per cent). a higher proportion of the strains of d nodosus than of the other strains had elastolytic activity, 118 of the 168 strains degrading elastin. species belonging to the genus prevotella were isolated from 96 cases (44.4 per cent). serotyping of the d nodosus strains showe ... | 1998 | 9481841 |
| serological classification and virulence determination of dichelobacter nodosus isolated from alberta and british columbia sheep. | ovine footrot is a contagious disease of sheep that occurs in temperature climates. it is caused by the strict anaerobe, dichelobacter nodosus. benign and virulent organisms are differentiated according to serotype and protease production. this study was conducted to identify the presence of virulent serotypes of d. nodosus in sheep flocks in alberta and british columbia. dichelobacter nodosus was detected in lame sheep from 11 of 15 (73%) flocks in alberta and in 4 of 5 (80%) british columbia f ... | 1998 | 9442937 |
| complementation analysis of the dichelobacter nodosus fimn, fimo, and fimp genes in pseudomonas aeruginosa and transcriptional analysis of the fimnop gene region. | the causative agent of ovine footrot, the gram-negative anaerobe dichelobacter nodosus, produces polar type iv fimbriae, which are the major protective antigens. the d. nodosus genes fimn, fimo, and fimp are homologs of the pseudomonas aeruginosa fimbrial assembly genes, pilb, pilc, and pild, respectively. both the pild and fimp genes encode prepilin peptidases that are responsible for cleavage of the leader sequence from the immature fimbrial subunit. to investigate the functional similarity of ... | 1998 | 9423871 |
| post-translational modifications of meningococcal pili. identification of common substituents: glycans and alpha-glycerophosphate--a review. | neisseria meningitidis elaborate filamentous adhesins, pili or fimbriae, which belong to the type-4 structural group of pili also found on other bacterial pathogens such as neisseria gonorrhoeae, pseudomonas aeruginosa, moraxella bovis and dichelobacter nodosus. meningococcal pili readily undergo structural variations which arise as a result of inter- and intra-genomic recombinational events. structural variations often result in variations in bacterial adhesion mediated by pili. studies on stru ... | 1997 | 9224884 |
| ulcerative pododermatitis in free-ranging african elephant (loxodonta africana) in the kruger national park. | the occurrence of severe lameness in adult african elephant bulls in a shrub mopane (colophospermum mopane) ecosystem was investigated. large ulcers in the soles of at least one front foot were seen in each of the recorded cases. microscopically, the lesion can be described as a severe, chronic-active, ulcerative, bacterial pododermatitis (complicated by hypersensitivity/septic vasculitis). a variety of bacteria were isolated from these lesions as well as from regional lymph nodes. streptococcus ... | 1997 | 9204500 |
| plasmid maintenance functions of the large virulence plasmid of shigella flexneri. | the large virulence plasmid pmysh6000 of shigella flexneri contains a replicon and a plasmid maintenance stability determinant (stb) on adjacent sali fragments. the presence of a repfiia replicon on the sali c fragment was confirmed, and the complete sequence of the adjacent sali o fragment was determined. it shows homology to part of the transfer (tra) operon of the f plasmid. stb stabilizes a partition-defective p1 miniplasmid in escherichia coli. a 1.1-kb region containing a homolog of the f ... | 1997 | 9171415 |
| high-level genetic diversity in the vapd chromosomal region of helicobacter pylori. | helicobacter pylori isolates from different patients are characterized by diversity in the nucleotide sequences of individual genes, variation in genome size, and variation in gene order. genetic diversity is particularly striking in vacuolating cytotoxin (vaca) alleles. in this study, five open reading frames (orfs) were identified within a 4.2-kb region downstream from vaca in h. pylori 60190. one of these orfs was closely related to the virulence-associated protein d (vapd) gene of dichelobac ... | 1997 | 9139899 |
| a retrospective study of clinical and laboratory characteristics of ovine footrot. | the infection of the feet of sheep by the anaerobic bacterium dichelobacter nodosus results in a spectrum of diseases ranging from virulent through intermediate to benign footrot. by examining the clinical characteristics of various forms of footrot from 22 properties in victoria, australia in association with the results of several laboratory tests including the gene probe-based dot blot hybridisation, it was shown that virulent footrot could not be differentiated from intermediate footrot usin ... | 1994 | 9133062 |
| improved laboratory diagnosis of ovine footrot: an update. | ovine footrot is a complex clinical disease syndrome primarily resulting from infection by the anaerobic bacterium dichelobacter nodosus. in order to aid clinical diagnosis, various laboratory tests based on the detection and measurements of phenotypic properties of d. nodosus have been developed for genus-specific detection as well as virulence determination. however, these tests are generally time-consuming, and tend to be variable with external factors that affect the growth and metabolism of ... | 1997 | 9125362 |
| antigens for serological diagnosis of ovine footrot. | an antigen extracted from dichelobacter nodosus with potassium thiocyanate (kscn) is currently used in enzyme-linked immunosorbent assay (elisa) for serological diagnosis of ovine footrot, but the test lacks specificity in mature sheep. other antigens were therefore evaluated for use in this test. structural components of the cell envelope of d. nodosus including outer membrane, cytoplasmic membrane, lipopolysaccharide and pilus and extracellular proteases were purified from cultured d. nodosus ... | 1997 | 9100327 |
| analysis of sequences flanking the vap regions of dichelobacter nodosus: evidence for multiple integration events, a killer system, and a new genetic element. | dichelobacter nodosus is the causative agent of ovine footrot. the vap regions of the d. nodosus genome may have arisen by the integration of a genetic element and may have a role in virulence. the virulent d. nodosus strain a198 has multiple copies of the vap regions. in the present study, sequences to the left and right of vap regions 1, 2 and 3 of strain a198 were analysed by southern blotting and dna sequencing. the results suggest that vap regions 1 and 2 rose by independent integration eve ... | 1997 | 9043132 |
| physical and genetic map of the chromosome of dichelobacter nodosus strain a198. | a physical map of the chromosome of dichelobacter nodosus strain a198 was constructed using the restriction endonucleases eagi and stui. mapping data indicated the presence of a single, circular chromosome of 1.54 mb. the three rrna operons and the virulence related locus (vrl) were precisely positioned at the junctions of eagi and stui fragments, and their transcriptional orientations were also determined. other d. nodosus genes were assigned to specific eagi and stui fragments. analysis of the ... | 1997 | 9031642 |
| effect of adjuvants on antibody responses of sheep immunised with recombinant pili from dichelobacter nodosus. | to compare the effects of two oil emulsion adjuvants (incomplete freunds adjuvant and a proprietary oil adjuvant), deae-dextran, l-tyrosine particles and quil a on the humoral immune responses of sheep immunised with recombinant pili of dichelobacter nodosus (strain a). | 1996 | 9006863 |
| identification, purification, and characterization of the type 4 fimbriae of pasteurella multocida. | the presence of fimbriae on pasteurella multocida has been reported, but there have been no prior studies aimed at conclusively characterizing these structures. we now report on the identification and characterization of type 4 fimbriae on serogroup a, b, and d strains of p. multocida. under microaerophilic conditions p. multocida showed an increased expression of the fimbriae, which were observed to form bundles. fimbriae purified by high-performance reverse-phase liquid chromatography constitu ... | 1997 | 8975936 |
| virulence regions and virulence factors of the ovine footrot pathogen, dichelobacter nodosus. | ovine footrot is a debilitating and highly infectious disease that is primarily caused by the gram-negative, anaerobic bacterium dichelobacter nodosus. the major antigens implicated in virulence are the type iv fimbriae and extracellular proteases. the fimbriae show sequence and structural similarity to other type iv fimbriae, this similarity extends to genes that are involved in fimbrial biogenesis. several acidic and basic extracellular serine proteases are produced by both virulent and benign ... | 1996 | 8961550 |
| the molecular genetics of type-4 fimbriae in pseudomonas aeruginosa--a review. | type-4 fimbriae (or pili) are filaments found at the poles of a wide range of bacterial pathogens, including neisseria gonorrhoeae, moraxella bovis, dichelobacter nodosus and pseudomonas aeruginosa. they are composed of a small subunit which is highly conserved among different species and appear to mediate adhesion and translocation across epithelial surfaces via a phenomenon termed "twitching motility'. these fimbriae are key host colonisation factors and important protective antigens. we have ... | 1996 | 8955641 |
| organization of ribosomal rna genes from the footrot pathogen dichelobacter nodosus. | southern hybridization analysis revealed that there were three rrn loci within the genome of dichelobacter nodosus, the causative organism of ovine footrot. these loci (rrna, rrnb and rrnc) were isolated on recombinant lambda clones, and comprised 16s, 23s and 5s rrna genes closely linked in that order. sequence and primer extension analysis revealed the presence of putative genes encoding trna(ile) and trna(ala) within the 16s-23s spacer region, as well as a number of potential regulatory featu ... | 1996 | 8936315 |