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studies in borreliae. i. a variant of borrelia parkeri davis 1942 isolated in california and its tick vector. 19654955802
genetic and phenotypic analysis of borrelia miyamotoi sp. nov., isolated from the ixodid tick ixodes persulcatus, the vector for lyme disease in japan.the ixodid tick ixodes persulcatus is the most important vector of lyme disease in japan. most spirochete isolates obtained from i. persulcatus ticks have been classified as borrelia burgdorferi sensu lato because of their genetic, biological, and immunological characteristics. however, we found that a small number of isolates obtained from i. persulcatus contained a smaller 38-kda endoflagellar protein and single 23s-5s rrna gene unit. representative isolate ht31t (t = type strain) had the same ...19957547303
comparison of borrelia isolated from uk foci of lyme disease.restriction endonuclease digestion of linear borrelial chromosomal dna showed that three isolates of uk lyme disease spirochaetes differed markedly from each other and from published data for other isolates from north america and continental europe. analysis of linear plasmid bands revealed that uk isolates differed from each other in the number and sizes of the plasmids in isolates from different foci of uk lyme disease. fatty acid analysis (of fatty acid methyl ester (fame) profiles) showed th ...19957649436
prevalence of antibodies to borrelia burgdorferi, borrelia parkeri and borrelia turicatae in human settlements of the cordillera province, bolivia.a seroepidemiological study to determine the prevalence of human lyme borreliosis and tick-borne relapsing fever was carried out in three communities (camiri, boyuibe and gutierrez) of the cordillera province, santa cruz department, south-eastern bolivia. anti-b. burgdorferi, anti-b. turicatae and anti-b. parkeri antibodies, tested by the indirect immunofluorescent assay (ifa), were detected in 10.8, 16.1 and 8.2% of the serum samples tested, and confirmed by ifa-abs in 1.3, 1.3 and 1.0%, respec ...19948107167
acylated proteins in borrelia hermsii, borrelia parkeri, borrelia anserina, and borrelia coriaceae.borrelia hermsii, borrelia parkeri, borrelia anserina, and borrelia coriaceae produced several lipoproteins identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography of bacteria grown in [3h]palmitate. five major acylated proteins were demonstrated by sequential alkaline and acid hydrolysis. high-pressure liquid chromatography of isolated proteins confirmed that covalently bound radioactivity was represented by fatty acids.19938285697
an ospa antigen-capture enzyme-linked immunosorbent assay for detecting north american isolates of borrelia burgdorferi in larval and nymphal ixodes dammini.an antigen-capture enzyme-linked immunosorbent assay (elisa) was developed for detecting north american isolates of borrelia burgdorferi in larval, nymphal, and adult ticks. the assay uses an anti-ospa monoclonal antibody (h5332) for antigen capture and biotin-labelled polyclonal sera with streptavidinhorseradish peroxidase for signal generation. the assay recognized 15 of 15 north american b. burgdorferi isolates and did not cross-react with spirochete antigens of borrelia hermsii, borrelia tur ...19938432812
uptake and killing of lyme disease and relapsing fever borreliae in the perfused rat liver and by isolated kupffer cells.in situ-perfused rat livers were infused with a single dose of 1.5 x 10(7) radiolabeled borreliae. significant (p < 0.00005) differences in the liver uptake of the agents of lyme borreliosis, borrelia burgdorferi irs, borrelia afzelii vs461, and borrelia garinii pbi, and that of the agents of relapsing fever, borrelia hermsii, borrelia parkeri, and borrelia turicatae, were observed. the liver uptakes ranged between 65.9% for b. burgdorferi irs and 40.5% for b. turicatae. neither relapsing fever ...19968613404
binding of human urokinase type plasminogen activator and plasminogen to borrelia species.borrelia burgdorferi binds human urokinase plasminogen activator (upa), which cleaves plasminogen (pgn) to plasmin. the ability of other borrelia species to bind upa, pgn, or both was investigated. borrelia coriacae, borrelia garinii, borrelia parkeri, borrelia anserina, and borrelia turicatae were compared with infectious and noninfectious b. burgdorferi isolates. all borrelia species lacked endogenous proteases capable of digesting casein, but all species bound human upa and pgn, generating pg ...19968656020
phylogenesis of relapsing fever borrelia spp.the phylogenetic relationships of 20 relapsing fever (rf) borrelia spp. were estimated on the basis of the sequences of rrs genes. complete sequences were aligned and compared with previously published sequences, and the similarity values were found to be 97.7 to 99.9%. phylogenetic trees were constructed by using the three neighbor-joining, maximum-parsimony, and maximum-likelihood methods. the results of the comparative phylogenetic analysis divided the rf borrelia spp. into three major cluste ...19968863409
phylogenetic analysis of borrelia species based on flagellin gene sequences and its application for molecular typing of lyme disease borreliae.we determined almost complete flagellin gene sequences of various borrelia species and aligned them with previously published sequences. a neighbor-joining phylogenetic analysis showed that the genus borrelia was divided into the following three major clusters: new world relapsing fever borreliae (borrelia turicatae, borrelia parkeri, and borrelia hermsii), old world relapsing fever borreliae (borrelia crocidurae, borrelia duttonii, and borrelia hispanica), and lyme disease borreliae (borrelia b ...19968863416
a phylogenetic analysis of borrelia burgdorferi sensu lato based on sequence information from the hbb gene, coding for a histone-like protein.we describe a phylogenetic investigation of borrelia burgdorferi sensu lato, the causative agent of lyme disease, based on a dna sequence analysis of the hbb gene, which encodes protein hbb, a member of the family of histone-like proteins. because of their intimate contact with the dna molecule, these proteins are believed to be fairly conserved through evolution. in this study we proved that the hbb gene is suitable for phylogenetic inference in the genus borrelia. the hbb gene, which is 327 bp ...19978995795
borrelia recurrentis characterization and comparison with relapsing-fever, lyme-associated, and other borrelia spp.borrelia recurrentis, the cause of louse-borne relapsing fever, has until recently been considered noncultivable, which has prevented characterization of this spirochete. we successfully cultivated 18 strains from patients with louse-borne relapsing fever and present the initial characterization of these isolates. electron microscopy revealed spirochetal cells with pointed ends, an average wavelength of 1.8 microns, an amplitude of 0.8 micron, and 8 to 10 periplasmic flagella. the g+c ratio was ...19979336893
isolation and characterization of the outer membrane of borrelia hermsii.the outer membrane of borrelia hermsii has been shown by freeze-fracture analysis to contain a low density of membrane-spanning outer membrane proteins which have not yet been isolated or identified. in this study, we report the purification of outer membrane vesicles (omv) from b. hermsii hs-1 and the subsequent identification of their constituent outer membrane proteins. the b. hermsii outer membranes were released by vigorous vortexing of whole organisms in low-ph, hypotonic citrate buffer an ...19989488399
a surface-exposed region of a novel outer membrane protein (p66) of borrelia spp. is variable in size and sequence.a model of the 66-kda outer membrane protein (p66) of lyme disease borrelia spp. predicts a surface-exposed loop near the c terminus. this region contains an antigen commonly recognized by sera from lyme disease patients. in the present study, this region of p66 and homologous proteins of other borrelia spp. were further investigated by using monoclonal antibodies, epitope mapping of p66 of borrelia burgdorferi, and dna sequencing. a monoclonal antibody specific for b. burgdorferi bound to the p ...19989537355
cloning and molecular characterization of a multicopy, linear plasmid-carried, repeat motif-containing gene from borrelia turicatae, a causative agent of relapsing fever.borrelia turicatae is one of several spirochete species that can cause relapsing fever. here, we describe the identification and characterization of a gene from b. turicatae and other relapsing-fever spirochetes that exhibits homology with the rep+ and orf-e gene families of the lyme disease spirochetes. this gene, which we have designated repa, encodes a putative protein of 30.2 kda with an isoelectric point of 4.69. the central region of repa harbors a series of amino acid repeat motifs which ...19989733706
tick-borne relapsing fever in british columbia, canada: first isolation of borrelia hermsii.the spirochete that causes tick-borne relapsing fever, borrelia hermsii, was isolated in pure culture during 1995 and 1996 from three acutely ill human patients infected in southern british columbia, canada. the geographic area of exposure is a known focus of this disease dating back to 1930 when the first case was recognized in a human. analyses of plasmid dna, protein profiles, and reactivity with a species-specific monoclonal antibody identified the new isolates of spirochetes as b. hermsii, ...19989817862
specific antibodies reactive with the 22-kilodalton major outer surface protein of borrelia anserina ni-nl protect chicks from infection.an outer surface lipoprotein of 22 kda was identified in the avian pathogen borrelia anserina ni-nl by using antibody preparations reactive with bacterial surface-exposed proteins. amino acid sequence analysis of the 22-kda protein demonstrated 90% identity with vmpa of b. turicatae, suggesting that the protein belongs to the family of 20-kda outer surface proteins of the genus borrelia. all of the 60 chicks intramuscularly treated with antibodies specifically reacting with the 22-kda protein an ...199910225933
molecular evidence for a new bacteriophage of borrelia burgdorferi.we have recovered a dnase-protected, chloroform-resistant molecule of dna from the cell-free supernatant of a borrelia burgdorferi culture. the dna is a 32-kb double-stranded linear molecule that is derived from the 32-kb circular plasmids (cp32s) of the b. burgdorferi genome. electron microscopy of samples from which the 32-kb dna molecule was purified revealed bacteriophage particles. the bacteriophage has a polyhedral head with a diameter of 55 nm and appears to have a simple 100-nm-long tail ...199910572135
genetic characteristics of borrelia coriaceae isolates from the soft tick ornithodoros coriaceus (acari: argasidae).two borrelia isolates (ca434 and ca435) cultured from the soft tick ornithodoros coriaceus were analyzed by contour-clamped homogeneous electric field gel electrophoresis of unrestricted and apai-restricted dna, standard electrophoresis of bamhi- and hindiii-restricted dna, southern hybridization, restriction fragment length polymorphism and sequencing of the 16s rrna gene, and amplification of the 5s-23s intergenic spacer region. these isolates were compared with borrelia coriaceae type strain ...200010878063
uptake and killing of leptospira interrogans and borrelia burgdorferi, spirochetes pathogenic to humans, by reticuloendothelial cells in perfused rat liver.in situ-perfused rat livers were infused with a single dose of 1.5 x 10(7) radiolabeled cells of leptospira interrogans serovar icterohaemorrhagiae, the agent of leptospirosis, or with borrelia burgdorferi irs, the agent of lyme disease. significant (p<0.0001) differences in the liver uptake of l. interrogans and of b. burgdorferi were observed, the uptakes being 37.4%+/-2.3% for l. interrogans and 60.5%+/-3.1% for b. burgdorferi. leptospires, in contrast to borreliae, were recovered from the li ...200010948172
serodiagnosis of louse-borne relapsing fever with glycerophosphodiester phosphodiesterase (glpq) from borrelia recurrentis.human louse-borne relapsing fever occurs in sporadic outbreaks in central and eastern africa that are characterized by significant morbidity and mortality. isolates of the causative agent, borrelia recurrentis, were obtained from the blood of four patients during a recent epidemic of the disease in southern sudan. the glpq gene, encoding glycerophosphodiester phosphodiesterase, from these isolates was sequenced and compared with the glpq sequences obtained from other relapsing-fever spirochetes. ...200011015364
isolation and characterization of borrelia parkeri in ornithodoros parkeri (ixodida: argasidae) collected in colorado.this study describes the identification of borrelia parkeri spirochetes in colorado. two isolates of b. parkeri (6230 and 6232) were recovered from ornithodoros parkeri cooley ticks collected at an inactive prairie dog town in moffat county. both isolates were partially characterized by sequencing and subsequent parsimony and neighbor-joining analyses of appropriate regions of the 16s ribosomal rna, flagellin and p66 genes. analyses of the 16s gene sequences from the colorado isolates indicated ...200111580039
equine abortion associated with the borrelia parkeri-b. turicatae tick-borne relapsing fever spirochete group.direct amplification and sequencing of the 16s rrna gene and a variable region of the flagellin gene from fetal liver-associated spirochetes belonging to the borrelia parkeri-b. turicatae tick-borne relapsing fever spirochete group with a late-term abortion in a mare are described.200211923397
evidence that the variable regions of the central domain of vlse are antigenic during infection with lyme disease spirochetes.it has been postulated that the vls system of the lyme disease spirochetes contributes to immune evasion through antigenic variation. while it is clear that vlse undergoes sequence change within its variable regions at a high frequency during the early stages of infection, a definitive role in immune evasion has not been demonstrated. in this report we assessed the murine and human humoral immune response to recombinant (r)-vlse variants that originally arose during infection in mice. immunoblot ...200212117928
analysis of the ability of spirochete species associated with relapsing fever, avian borreliosis, and epizootic bovine abortion to bind factor h and cleave c3b.some borrelia species associated with lyme disease bind the complement-regulatory protein factor h (fh), a process that may aid in immune evasion. in this report we demonstrate that some borrelia species associated with relapsing fever bind fh, but not those associated with avian borreliosis and epizootic bovine abortion. cell-bound fh was also found to mediate cleavage of exogenously supplied human c3b, demonstrating the biological relevance of fh binding and its possible importance in the path ...200312904415
a novel, fast-growing borrelia sp. isolated from the hard tick hyalomma aegyptium in turkey.a novel, fast-growing spirochaete was isolated from the hard tick hyalomma aegyptium (family ixodidae, subfamily metastriata) using barbour-stoenner-kelly (bsk) ii medium. tick samples were taken during the summer of 2000 from the istanbul area in northwestern turkey. sixty-seven of 153 adults (44%) and 72 of 185 nymphs (39%) were infected with the novel spirochaete, whereas none of the 20 larvae examined were infected. the optimal growth temperature of the spirochaete in bsk ii medium was 34-37 ...200312949178
relapsing fever spirochetes: an aberrant strain of borrelia parkeri from oregon. 195514365775
tick-borne relapsing fever caused by borrelia hermsii, montana.five persons contracted tick-borne relapsing fever after staying in a cabin in western montana. borrelia hermsii was isolated from the blood of two patients, and ornithodoros hermsi ticks were collected from the cabin, the first demonstration of this bacterium and tick in montana. relapsing fever should be considered when patients who reside or have vacationed in western montana exhibit a recurring febrile illness.200314519254
isolation and characterization of borrelia hermsii associated with two foci of tick-borne relapsing fever in california.relapsing fever, caused by the spirochete borrelia hermsii and transmitted by the soft tick ornithodoros hermsi, is endemic in many rural mountainous areas of california. between 1996 and 1998, 12 cases of relapsing fever associated with two exposure sites in northern california were investigated. follow-up at exposure sites included collection of soft ticks and serum specimens from sylvatic rodents. attempts to cultivate spirochetes were made through inoculation of patient blood into mice and b ...200415004063
identification and characterization of a linear-plasmid-encoded factor h-binding protein (fhba) of the relapsing fever spirochete borrelia hermsii.in north america, tick-borne relapsing fever (tbrf) is caused by the spirochete species borrelia hermsii, borrelia parkeri, and borrelia turicatae. we previously demonstrated that some isolates of b. hermsii and b. parkeri are capable of binding factor h and that cell-bound factor h can participate in the factor i-mediated cleavage of c3b. isolates that bound factor h expressed a factor h-binding protein (fhbp) that we estimated to be approximately 19 to 20 kda in size and thus, pending further ...200415090501
glycerophosphodiester phosphodiesterase gene (glpq) of borrelia lonestari identified as a target for differentiating borrelia species associated with hard ticks (acari:ixodidae).a glpq ortholog was identified in dna from borrelia lonestari-positive amblyomma americanum, providing further evidence that b. lonestari is more closely related to the relapsing fever group spirochetes than to borreliae that cause lyme disease. this finding provides a basis for developing diagnostic assays to differentiate species of borrelia transmitted by hard ticks.200415131225
multiplex real-time pcr for detection of anaplasma phagocytophilum and borrelia burgdorferi.a multiplex real-time pcr assay was developed for the simultaneous detection of anaplasma phagocytophilum and borrelia burgdorferi. the assay was tested on various anaplasma, borrelia, erhlichia, and rickettsia species, as well as on bartonella henselae and escherichia coli, and the assay was found to be highly specific for a. phagocytophilum and the borrelia species tested (b. burgdorferi, b. parkeri, b. andersonii, and b. bissettii). the analytical sensitivity of the assay is comparable to tha ...200415243077
identification of a new borrelia species among small mammals in areas of northern spain where lyme disease is endemic.the role of small mammals as reservoir hosts for borrelia burgdorferi was investigated in several areas where lyme disease is endemic in northern spain. a low rate of infestation by ixodes ricinus nymphs was found in the small mammal populations studied that correlated with the near-absence of b. burgdorferi sensu lato in 184 animals tested and with the lack of transmission of b. burgdorferi sensu lato to i. ricinus larvae that fed on them. in contrast, questing ticks collected at the same time ...200515746336
'candidatus borrelia texasensis', from the american dog tick dermacentor variabilis.txw-1, a borrelia strain isolated in march 1998 from an adult male dermacentor variabilis tick feeding on a coyote from webb county, texas, usa, was characterized by using randomly amplified polymorphic dna (rapd) analysis, rflp and sequence analysis of flab and rrs (16s rrna gene), dna-dna hybridization analysis, sds-page and western blotting with mabs. it shows different banding patterns in rflp analysis of flab and forms distinct branches in phylogenetic analysis derived from flab and rrs gen ...200515774644
phylogenetic analysis of the spirochetes borrelia parkeri and borrelia turicatae and the potential for tick-borne relapsing fever in florida.isolates of borrelia turicatae, borrelia parkeri, and the florida canine borrelia (fcb) were examined to further phylogenetically characterize the identities of these spirochetes in the united states. dna sequences of four chromosomal loci (the 16s rrna gene, flab, gyrb, and glpq) were determined for eight isolates of b. turicatae and six isolates of b. parkeri, which grouped the spirochetes into two distinct but closely related taxa (>98% sequence identity) separate from borrelia hermsii. the f ...200516081922
variable tick protein in two genomic groups of the relapsing fever spirochete borrelia hermsii in western north america.borrelia hermsii is the primary cause of tick-borne relapsing fever in north america. when its tick vector, ornithodoros hermsi, acquires these spirochetes from the blood of an infected mammal, the bacteria switch their outer surface from one of many bloodstream variable major proteins (vmps) to a unique protein, vtp (vsp33). vtp may be critical for successful tick transmission of b. hermsii; however, the gene encoding this protein has been described previously in only one isolate. here we ident ...200516177341
demonstration of factor h-like protein 1 binding to treponema denticola, a pathogen associated with periodontal disease in humans.treponema denticola is an important contributor to periodontal disease. in this study we investigated the ability of t. denticola to bind the complement regulatory proteins factor h and factor h-like protein 1 (fhl-1). the binding of these proteins has been demonstrated to facilitate evasion of the alternative complement cascade and/or to play a role in adherence and invasion. here we demonstrate that t. denticola specifically binds fhl-1 via a 14-kda, surface-exposed protein that we designated ...200516239506
molecular analyses of the interaction of borrelia hermsii fhba with the complement regulatory proteins factor h and factor h-like protein 1.borrelia hermsii, the primary etiological agent of tick-borne relapsing fever in north america, binds the complement regulatory protein factor h (fh) as a means of evading opsonophagocytosis and the alternative complement pathway. the ability of fh-binding protein a (fhba) to bind fh-like protein 1 (fhl-1) has not been assessed previously. in this study, using a whole-cell absorption assay, we demonstrated that b. hermsii absorbs both fh and fhl-1 from human serum. consistent with this, affinity ...200616552029
immunological and molecular analyses of the borrelia hermsii factor h and factor h-like protein 1 binding protein, fhba: demonstration of its utility as a diagnostic marker and epidemiological tool for tick-borne relapsing fever.it has been demonstrated that borrelia hermsii, a causative agent of relapsing fever, produces a factor h (fh) and fh-like protein 1 (fhl-1) binding protein. the binding protein has been designated fhba. to determine if fh/fhl-1 binding is widespread among b. hermsii isolates, a diverse panel of strains was tested for the fh/fhl-1 binding phenotype and fhba production. most isolates (23/24) produced fhba and bound fh/fhl-1. potential variation in fhba among isolates was analyzed by dna sequence ...200616861638
identification of pathogenic leptospira species by conventional or real-time pcr and sequencing of the dna gyrase subunit b encoding gene.leptospira is the causative genus of the disease, leptospirosis. species identification of pathogenic leptospira in the past was generally performed by either dna-dna hybridisation or 16s rrna gene sequencing. both methods have inherent disadvantages such as the need for radio-labelled isotopes or significant homology between species. a conventional and real-time pcr amplification and sequencing method was developed for an alternate gene target: dna gyrase subunit b (gyrb). phylogenetic comparis ...200617067399
purine salvage pathways among borrelia species.genome sequencing projects on two relapsing fever spirochetes, borrelia hermsii and borrelia turicatae, revealed differences in genes involved in purine metabolism and salvage compared to those in the lyme disease spirochete borrelia burgdorferi. the relapsing fever spirochetes contained six open reading frames that are absent from the b. burgdorferi genome. these genes included those for hypoxanthine-guanine phosphoribosyltransferase (hpt), adenylosuccinate synthase (pura), adenylosuccinate lya ...200717502392
an insight into the sialome of the soft tick, ornithodorus parkeri.while hard ticks (ixodidae) take several days to feed on their hosts, soft ticks (argasidae) feed faster, usually taking less than 1h per meal. saliva assists in the feeding process by providing a cocktail of anti-hemostatic, anti-inflammatory and immunomodullatory compounds. saliva of hard ticks has been shown to contain several families of genes each having multiple members, while those of soft ticks are relatively unexplored. analysis of the salivary transcriptome of the soft tick ornithodoru ...200818070662
novel relapsing fever spirochete in bat tick. 200818325285
relapsing fever spirochetes retain infectivity after prolonged in vitro cultivation.borrelia hermsii and borrelia burgdorferi, two closely related spirochetes, are the etiological agents of tick-borne relapsing fever and lyme disease, respectively. previous studies have shown the loss of infectivity of b. burgdorferi is associated with in vitro cultivation. this diminished infectivity of b. burgdorferi has occurred as early as three in vitro passages, and the loss of plasmids have been observed with these less virulent to noninfective cultures. the effects of long-term in vitro ...200818637723
tick-borne relapsing fever.each year, many residents of and visitors to endemic regions of the western united states are exposed to the tick vectors of tick-borne relapsing fever (tbrf), ornithodoros hermsi, ornithodoros turicata, or ornithodoros parkeri. this disease is remarkable because the human host is unaware of the tick bite, usually becomes very ill, may experience an exacerbation of symptoms rather than improvement shortly after beginning appropriate treatment, and, despite often high numbers of the etiologic org ...200818755384
characterization of a novel relapsing fever spirochete in the midgut, coxal fluid, and salivary glands of the bat tick carios kelleyi.bat ticks, carios kelleyi, from iowa were examined for the presence of relapsing fever group borreliae. a novel spirochete was characterized by dna sequence analysis of polymerase chain reaction amplicons for the 16s rrna, flab, and glpq genes in either triturated tick pools or single ticks. all loci and the concatenated dna sequence of 3,289 bases identified the carios bacterium as a relapsing fever spirochete most closely related to, but distinct from, borrelia turicatae. spirochetes reactive ...200919281412
identification of the determinant conferring permissive substrate usage in the telomere resolvase, rest.linear genome stability requires specialized telomere replication and protection mechanisms. a common solution to this problem in non-eukaryotes is the formation of hairpin telomeres by telomere resolvases (also known as protelomerases). these enzymes perform a two-step transesterification on replication intermediates to generate hairpin telomeres using an active site similar to that of tyrosine recombinases and type ib topoisomerases. unlike phage telomere resolvases, the telomere resolvase fro ...200919561077
a novel surface antigen of relapsing fever spirochetes can discriminate between relapsing fever and lyme borreliosis.in a previous immunoproteome analysis of borrelia hermsii, candidate antigens that bound igm antibodies from mice and patients infected with relapsing fever spirochetes were identified. one candidate that was identified is a hypothetical protein with a molecular mass of 57 kda that we have designated borrelia immunogenic protein a (bipa). this protein was further investigated as a potential diagnostic antigen for b. hermsii given that it is absent from the borrelia burgdorferi genome. the bipa l ...201020147497
molecular characterization of the interaction of borrelia parkeri and borrelia turicatae with human complement regulators.in north america, tick-borne relapsing fever is caused by the species borrelia hermsii, b. parkeri, and b. turicatae, which are transmitted to humans through the bite of the respective infected tick vectors. here we describe the identification and functional characterization of a surface lipoprotein of b. parkeri, designated bpca, that binds the human complement regulators factor h and factor h-related protein 1 and, simultaneously, the host protease plasminogen. in contrast, the homologous b. t ...201020231403
endemic foci of the tick-borne relapsing fever spirochete borrelia crocidurae in mali, west africa, and the potential for human infection.tick-borne relapsing fever spirochetes are maintained in endemic foci that involve a diversity of small mammals and argasid ticks in the genus ornithodoros. most epidemiological studies of tick-borne relapsing fever in west africa caused by borrelia crocidurae have been conducted in senegal. the risk for humans to acquire relapsing fever in mali is uncertain, as only a few human cases have been identified. given the high incidence of malaria in mali, and the potential to confuse the clinical dia ...201223209863
first isolation of the relapsing fever spirochete, borrelia hermsii, from a domestic dog.in north america, tick-borne relapsing fever of humans is most frequently caused by infection with the spirochete borrelia hermsii. prior to our investigation, this spirochete was not known to infect dogs although another species, borrelia turicatae, has been isolated from domestic canids in florida and texas. a clinically ill dog in washington, usa, was spirochetemic upon examination. spirochetes were isolated from the dog's serum and examined by pcr and multi-locus sequence typing. dna sequenc ...201324252262
first isolation of the relapsing fever spirochete, borrelia hermsii, from a domestic dog.in north america, tick-borne relapsing fever of humans is most frequently caused by infection with the spirochete borrelia hermsii. prior to our investigation, this spirochete was not known to infect dogs although another species, borrelia turicatae, has been isolated from domestic canids in florida and texas. a clinically ill dog in washington, usa, was spirochetemic upon examination. spirochetes were isolated from the dog's serum and examined by pcr and multi-locus sequence typing. dna sequenc ...201324252262
a guide to utilization of the microbiology laboratory for diagnosis of infectious diseases: 2013 recommendations by the infectious diseases society of america (idsa) and the american society for microbiology (asm)(a).the critical role of the microbiology laboratory in infectious disease diagnosis calls for a close, positive working relationship between the physician and the microbiologists who provide enormous value to the health care team. this document, developed by both laboratory and clinical experts, provides information on which tests are valuable and in which contexts, and on tests that add little or no value for diagnostic decisions. sections are divided into anatomic systems, including bloodstream i ...201323845951
multiplex real-time pcr diagnostic of relapsing fevers in africa.in africa, relapsing fever borreliae are neglected arthropod-borne pathogens causing mild to deadly septicemia and miscarriage. the closely related borrelia crocidurae, borrelia duttonii, borrelia recurrentis and borrelia hispanica are rarely diagnosed at the species level, hampering refined epidemiological and clinical knowledge of the relapsing fevers. it would be hugely beneficial to have simultaneous detection and identification of borrelia to species level directly from clinical samples.201323390560
case report: a retrospective serological analysis indicating human exposure to tick-borne relapsing fever spirochetes in texas. 201525856342
host associations and genomic diversity of borrelia hermsii in an endemic focus of tick-borne relapsing fever in western north america.an unrecognized focus of tick-borne relapsing fever caused by borrelia hermsii was identified in 2002 when five people became infected on wild horse island in flathead lake, montana. the terrestrial small mammal community on the island is composed primarily of pine squirrels (tamiasciurus hudsonicus) and deer mice (peromyscus maniculatus), neither of which was known as a natural host for the spirochete. thus a 3-year study was performed to identify small mammals as hosts for b. hermsii.201627832805
consensus computational network analysis for identifying candidate outer membrane proteins from borrelia spirochetes.similar to gram-negative organisms, borrelia spirochetes are dual-membrane organisms with both an inner and outer membrane. although the outer membrane contains integral membrane proteins, few of the borrelial outer membrane proteins (omps) have been identified and characterized to date. therefore, we utilized a consensus computational network analysis to identify novel borrelial omps.201627400788
novel borrelia species detected in echidna ticks, bothriocroton concolor, in australia.to date, little has been documented about microorganisms harboured within australian native ticks or their pathogenic potential. recently, a borrelia sp. related to the relapsing fever (rf) group was identified in a single tick removed from a wild echidna (tachyglossus aculeatus). the present study investigated the presence of borrelia in 97 bothriocroton concolor ticks parasitizing echidnas in queensland, new south wales, and victoria, australia, using nested pcr with borrelia-specific primers ...201627301754
transcriptional profiling the 150 kb linear megaplasmid of borrelia turicatae suggests a role in vector colonization and initiating mammalian infection.adaptation is key for survival as vector-borne pathogens transmit between the arthropod and vertebrate, and temperature change is an environmental signal inducing alterations in gene expression of tick-borne spirochetes. while plasmids are often associated with adaptation, complex genomes of relapsing fever spirochetes have hindered progress in understanding the mechanisms of vector colonization and transmission. we utilized recent advances in genome sequencing to generate the most complete vers ...201626845332
sequence analysis and serological responses against borrelia turicatae bipa, a putative species-specific antigen.relapsing fever spirochetes are global yet neglected pathogens causing recurrent febrile episodes, chills, nausea, vomiting, and pregnancy complications. given these nonspecific clinical manifestations, improving diagnostic assays for relapsing fever spirochetes will allow for identification of endemic foci and expedite proper treatment. previously, an antigen designated the borrelia immunogenic protein a (bipa) was identified in the north american species borrelia hermsii. thus far, bipa appear ...201324069498
genome sequence of borrelia parkeri, an agent of enzootic relapsing fever in western north america.borrelia parkeri is a relapsing fever agent that rarely causes human infection, unlike other north american species. b. parkeri strain hr1 was isolated from ornithodoros parkeri ticks. the sequences of its linear chromosome and large plasmid were determined by next-generation sequencing. these confirmed its closer relatedness to borrelia turicatae than to borrelia hermsii.201424526628
chromosome and linear plasmid sequences of a 2015 human isolate of the tick-borne relapsing fever spirochete, borrelia turicatae.the sequences of the complete linear chromosome and 7 linear plasmids of the relapsing fever spirochete borrelia turicatae are presented in this report. the 925,547 bp of chromosome and 380,211 bp of plasmid sequence were predicted to contain a total of 1,131 open reading frames, with an average g+c content of 29.7%.201627417836
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