| lipid metabolism of borrelia hermsi. | the synthesis of complex lipids by borrelia hermsi while growing in kelly medium was investigated by labeling cultures with d-[14c]glucose or [14c]palmitic acid. labeled glucose was incorporated into phosphatidyl choline, phosphatidyl glycerol, monogalactosyl diglyceride, cholesterol glucoside, and acylated cholesteryl glucoside. the fatty acid composition reflected that of the medium suggesting that this spirochete directly incorporates acyl chains unaltered from its external milieu. furthermor ... | 1978 | 669794 |
| reinfection of vervet monkeys (cercopithecus aethiops) with borrelia hermsii. | two of 4 untreated vervet monkeys infected with borrelia hermsii survived and were resistant to reinfection for at least 1 year. seven of 9 vervets receiving tetracycline could be reinfected after 12 to 36 weeks. immobilizine could be demonstrated for a shorter time in treated than in untreated vervets. | 1975 | 807959 |
| polymerase chain reaction for detection of leptospira spp. in clinical samples. | a sensitive assay for leptospira spp., the causative agent of leptospirosis, was developed on the basis of the polymerase chain reaction (pcr). a 331-bp sequence from the leptospira interrogans serovar canicola rrs (16s) gene was amplified, and the pcr products were analyzed by dna-dna hybridization by using a 289-bp fragment internal to the amplified dna. specific pcr products also were obtained with dna from the closely related nonpathogenic leptospira biflexa but not with dna from other spiro ... | 1992 | 1400983 |
| seroprevalence survey of borreliosis in children with chronic arthritis in british columbia, canada. | a seroprevalence survey using an indirect immunofluorescence assay (ifa) for igg antibodies to borrelia hermsii and borrelia burgdorferi was conducted for varied pediatric chronic arthritis patients and a nonrheumatic control group in the province of british columbia, canada. overall, a higher rate of sera with ifa titers > or = 1/256 was found for b. hermsii (36.6%) compared to b. burgdorferi (12.5%). there were no significant differences among the arthritis subgroups and controls for the distr ... | 1992 | 1464879 |
| identification of the tick-borne relapsing fever spirochete borrelia hermsii by using a species-specific monoclonal antibody. | borrelia hermsii causes a relapsing fever in humans and is one of several species of tick-borne spirochetes known to occur in the western united states. spirochetes observed in the peripheral blood of patients acutely ill have been presumptively identified in the past by the geographic location of exposure and the probable species of tick vector. we describe a monoclonal antibody (h9826) that bound to the flagellar protein of b. hermsii but not to those of any of the other species tested, which ... | 1992 | 1572965 |
| cross-reactive proteins of borrelia burgdorferi. | the specificity of serological tests for lyme borreliosis is impaired by cross-reacting antibodies. in order to select antigens for more specific tests, specific and cross-reactive proteins of borrelia burgdorferi must be identified. therefore, to analyze cross reactions of borrelia burgdorferi with other bacteria, rabbit immune sera against heterologous bacteria (borrelia hermsii, treponema pallidum, treponema phagedenis, leptospira interrogans (serogroup grippotyphosa), neisseria meningitidis, ... | 1992 | 1597198 |
| borrelia burgdorferi and other related spirochetes bind to galactocerebroside. | spirochetes are agents of neurologic disease that may utilize specific neural cell surface molecules for adhesion. borrelia burgdorferi, the etiologic agent of lyme disease, bound to galactocerebroside (galcer) in numbers that were two- to threefold greater than to ceramide and glucocerebroside, and four- to fivefold greater than to sphingosine, psychosine, sulfatide, cholesterol, and three membrane phospholipids. the adherence was greater to galcer and ceramide with a higher content of alpha-hy ... | 1992 | 1620344 |
| detection of borrelia burgdorferi dna in urine samples and cerebrospinal fluid samples from patients with early and late lyme neuroborreliosis by polymerase chain reaction. | a polymerase chain reaction (pcr) was developed for use in the identification of a 248-bp fragment of the borrelia burgdorferi flagellin gene in urine and cerebrospinal fluid (csf) from patients with lyme neuroborreliosis. the specificities of the pcr products were confirmed by dna-dna hybridization with an internal probe. the assay had a detection limit of 10 in vitro-cultivated b. burgdorferi. the pcr assay seemed to be species wide as well as species specific, since dna from all 21 b. burgdor ... | 1992 | 1629318 |
| selection of an escape variant of borrelia burgdorferi by use of bactericidal monoclonal antibodies to ospb. | two immunoglobulin g (igg) monoclonal antibodies (mabs) to outer surface protein b (cb2 and cb6), affinity purified from mouse ascitic fluid, exhibited concentration-dependent inhibitory and bactericidal properties against borrelia burgdorferi after a 24-h incubation period in spirochete medium. fab fragments derived from these mabs showed the same effects, indicating that they were not caused by agglutination of the organisms by the intact mabs. the inhibition of spirochete growth in cultures c ... | 1992 | 1639477 |
| comparative ability of various detergents to extract proteins of borrelia burgdorferi and borrelia hermsii. | borrelia burgdorferi and borrelia hermsii were treated with the following detergents: sodium dodecyl sulphate (sds), n-lauryl sarcosine (sarkosyl) and triton x-100, and the soluble and insoluble fractions obtained after each detergent treatment were examined by sodium dodecyl sulphate polyacrylamide gel electrophoresis. sarkosyl as well as sds solubilized all borrelia proteins, whereas triton x-100 treatment selectively solubilized the majority of other borrelial proteins, leaving two proteins o ... | 1991 | 1723136 |
| polymerase chain reaction primers and probes derived from flagellin gene sequences for specific detection of the agents of lyme disease and north american relapsing fever. | by cloning and sequencing the flagellin gene of borrelia hermsii and comparing this sequence with that of the corresponding gene from b. burgdorferi, i identified a central region within the two genes which showed a reduced level of sequence similarity. oligonucleotide sequences selected from this region produced species-specific amplimers when used in polymerase chain reaction experiments. thus, primers derived from the b. burgdorferi sequence amplified a 276-bp fragment from 22 strains of b. b ... | 1992 | 1734073 |
| characterization of borrelia coriaceae antigens with monoclonal antibodies. | three monoclonal antibodies (f6f3, f6b11, and f6b3) were developed against borrelia coriaceae antigens. all three antibodies appeared to be specific for this species and did not cross-react with borrelia burgdorferi (strains b31 and irs), borrelia hermsii, borrelia anserina, leptospira interrogans serovar hardjo, or treponema hyodysenteriae, as determined by indirect fluorescent antibody staining, enzyme-linked immunosorbent assay, and western immunoblot analysis. only one of these antibodies, f ... | 1991 | 1855995 |
| analysis of outer membrane ultrastructure of pathogenic treponema and borrelia species by freeze-fracture electron microscopy. | we analyzed the outer membrane (om) ultrastructure of four pathogenic members of the family spirochaetaceae by freeze fracture. the om of treponema pallidum subsp. pertenue contained a low intramembranous particle concentration, indicating that it contains few om transmembrane proteins. the concave om fracture faces of treponema hyodysenteriae and borrelia burgdorferi contained dense populations of particles, typical of gram-negative organisms. a relatively low concentration of particles which w ... | 1991 | 1885536 |
| phylogenetic analysis of the spirochetes. | the 16s rrna sequences were determined for species of spirochaeta, treponema, borrelia, leptospira, leptonema, and serpula, using a modified sanger method of direct rna sequencing. analysis of aligned 16s rrna sequences indicated that the spirochetes form a coherent taxon composed of six major clusters or groups. the first group, termed the treponemes, was divided into two subgroups. the first treponeme subgroup consisted of treponema pallidum, treponema phagedenis, treponema denticola, a thermo ... | 1991 | 1917844 |
| antigenic variation in borrelia. | antigenic variation was demonstrated for the agent of relapsing fever, borrelia hermsii. the phenomenon is correlated with changes in major surface proteins called vmp. the genes encoding these antigens are located on linear plasmids. expression occurs by transposition of genes encoding vmp to a telomeric expression site located on another linear plasmid. activation of a vmp gene occurs by placing it downstream from a promoter. resemblance to the antigenic variation of trypanosomes is discussed. | 1991 | 1961981 |
| tandem insertion sequence-like elements define the expression site for variable antigen genes of borrelia hermsii. | the spirochete borrelia hermsii avoids the immune response of its mammalian host through multiphasic antigenic variation. serotype specificity is determined by variable antigens, vmp proteins, in the outer membrane. through nonreciprocal recombination between linear plasmids, a formerly silent vmp gene replaces another vmp gene downstream from a common expression site. to further characterize this activating site, we determined the nucleotide sequence of 6.9 kb of the common upstream expression ... | 1991 | 1987053 |
| characterization of an immunoreactive 93-kda core protein of borrelia burgdorferi with a human igg monoclonal antibody. | lyme borreliosis is an infectious disease caused by the tick-borne spirochete borrelia burgdorferi, which carries the potential for chronic infection. ag on the etiologic borrelia are currently being defined structurally and their ability to elicit immune responses delineated. ebv can be used to immortalize human b. burgdorferi-specific b cells from infected donors and generate antibodies against antigenic epitopes encountered in natural infection. a human mab secreting ebv-transformed b cell li ... | 1991 | 2016542 |
| polymerase chain reaction analyses identify two distinct classes of borrelia burgdorferi. | we sequenced homologous chromosomal loci from several north american and european isolates of the lyme disease spirochete borrelia burgdorferi, as well as from the relapsing fever spirochete borrelia hermsii. inter- and intraspecies sequence comparisons permitted the design of b. burgdorferi-specific polymerase chain reaction primers that detected all strains tested (n = 31) from diverse geographical and biological origins. polymerase chain reaction "typing" with other unique sets of primers sub ... | 1991 | 2037670 |
| comparative in vitro and in vivo susceptibilities of the lyme disease spirochete borrelia burgdorferi to cefuroxime and other antimicrobial agents. | the in vitro and in vivo susceptibilities of the lyme disease pathogen borrelia burgdorferi to cefuroxime were compared with those of several other antibiotics commonly used to treat this disease. cefuroxime demonstrated a higher mbc in vitro (1.0 microgram/ml) than ceftriaxone (0.08 microgram/ml) or erythromycin (0.32 microgram/ml), but the mbc was similar to that of amoxicillin (0.8 microgram/ml) and doxycycline (1.6 micrograms/ml). b. burgdorferi was considerably less susceptible to tetracycl ... | 1990 | 2073103 |
| in-vitro susceptibility of borrelia burgdorferi and borrelia hermsii to ten antimicrobial agents. | the in-vitro activity of ten antimicrobial agents against four strains of borrelia burgdorferi originating both in the united states and europe and against one isolate of b. hermsii was investigated. ceftriaxone, erythromycin and roxithromycin were the most active drugs against both borrelia species studied, with minimum bactericidal concentrations ranging from 0.015 micrograms/ml to 0.125 micrograms/ml. | 1990 | 2093104 |
| interlaboratory and intralaboratory comparisons of indirect immunofluorescence assays for serodiagnosis of lyme disease. | a conventional indirect immunofluorescence assay (ifa) and an anticomplement indirect immunofluorescence assay (acif) for detecting serum antibodies to borrelia burgdorferi in humans were evaluated during a prevalence survey in northern california. sera obtained from 119 current or former residents of an area in which lyme disease is endemic were split and tested by the ifa in two laboratories and the acif in a third. the seropositivity rate ranged from 15 to 20% with 88 to 93% agreement among l ... | 1990 | 2203813 |
| borrelia burgdorferi contains repeated dna sequences that are species specific and plasmid associated. | borrelia burgdorferi, the causative agent of lyme borreliosis, contains linear and supercoiled circular (sc) plasmids. because sc plasmids are present in multiple copies, these plasmids were examined for species-specific sequences that could serve as high-copy-number target dnas for a diagnostic probe. three ecori fragments (4.3, 4.2, and 3.5 kilobase pairs [kb]) that hybridized with multiple dna fragments from b. burgdorferi were identified and cloned from a sc plasmid-enriched fraction. the 4. ... | 1990 | 2318533 |
| shared flagellar epitopes of borrelia burgdorferi and borrelia anserina. | antigenic cross-reactivity between borrelia burgdorferi and borrelia anserina was studied using mouse immune sera and monoclonal antibodies. with immune sera, significant cross-reactivity between b. burgdorferi and b. anserina was demonstrated by indirect immunofluorescent assay. in immunoblots, most of the cross-reactivity was shown to be associated with the periplasmic flagella. using monoclonal antibodies in immunoblots, it was shown that b. burgdorferi and b. anserina shared at least two fla ... | 1989 | 2473569 |
| antigenic variation is associated with dna rearrangements in a relapsing fever borrelia. | borrelia hermsii, an agent of relapsing fever, undergoes antigenic variation in its host. surface-exposed proteins with differing primary structures determine the serotype of each organism. using amino acid sequence data from two of these variable proteins, we synthesized two mixed-sequence oligonucleotides and then used the oligonucleotides to probe mrna and dna of three isogenic serotypes of b. hermsii. in northern blots the probes were specific for the mrna of the homologous serotype. souther ... | 1985 | 2580643 |
| development of transplantable ascites tumours which continuously produce polyclonal antibodies in pristane primed balb/c mice immunized with bacterial antigens and complete freund's adjuvant. | bacterial immunogens (whole cells of borrelia burgdorferi, elementary bodies of chlamydia trachomatis and purified proteins of 22 and 24 kda of borrelia hermsii) were emulsified with an excess of complete freund's adjuvant and injected (i.p.) on days 0, 7, 14 and 21, into balb/c mice treated with pristane on day 6. this procedure induced the development of antibody-producing ascites tumours which could be serially transplanted in pristane-conditioned mice. ascites tumours continued to yield a co ... | 1991 | 2061607 |
| comparison of in vitro culture and polymerase chain reaction for detection of borrelia burgdorferi in tissue from experimentally infected animals. | a polymerase chain reaction (pcr) was developed for identification of borrelia burgdorferi in biological specimens. the diagnostic efficiency was compared with that of in vitro culture. a primer set specifying a 791-bp dna fragment of the b. burgdorferi b31 flagellin gene was used. amplified dna sequences were analyzed by agarose gel electrophoresis, and the identity of amplified dna was confirmed by restriction enzyme cleavage and southern blot hybridization with a 32p-labeled probe. by using p ... | 1991 | 1890174 |
| relapsing fever/lyme disease. multiple sclerosis. | lyme disease and relapsing fever caused by borrelia burdorferi and borrelia hermsii, respectively, have been generally considered curable if diagnosed early. however, it is becoming apparent that when these diseases are left undiagnosed and untreated they may cause severe problems for some people. they, in fact, may be one of the major causes of multiple sclerosis. these two borrelia infections, when left untreated, are now known to be capable of causing neurological problems, cardiac problems, ... | 1986 | 3642202 |
| isolation of the outer envelope, chemical components, and ultrastructure of borrelia hermsi grown in vitro. | | 1979 | 41419 |
| experimental relapsing fever initiated by borrelia hermsi. ii. sequential appearance of major serotypes in the rat. | | 1967 | 5338694 |
| antigenic variation of surface proteins of borrelia species. | during relapsing fever, the etiologic spirochetes employ antigenic variation to avoid early immune clearance. in borrelia hermsii, an agent of tick-borne relapsing fever, a switch in serotype is associated with a change in the predominant protein on the surface of the cells. the variable major proteins differ from one another in primary structure along their lengths. genes encoding the different variable major proteins can be found in both "silent" and "active" environments. at the active site t ... | 1988 | 3055207 |
| antigenic cross-reactivity between treponema pallidum and other pathogenic members of the family spirochaetaceae. | the antigenic cross-reactivity between treponema pallidum and several pathogenic members of the family spirochaetaceae was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blotting techniques. blots of t. pallidum antigens were incubated with antiserum from rabbits infected or immunized with t. pallidum, treponema paraluiscuniculi, treponema hyodysenteriae (strains b204 and t22), borrelia hermsii serotype 7, or leptopsira interrogans serogroup canicola. t. pallid ... | 1984 | 6384040 |
| the antibody response in lyme disease. | we determined the antibody response against the ixodes dammini spirochete in lyme disease patients by indirect immunofluorescence and an enzyme-linked immunosorbent assay (elisa). the specific igm response became maximal three to six weeks after disease onset, and then declined, although titers sometimes remained elevated during later disease. specific igm levels correlated directly with total serum igm. the specific igg response, often delayed initially, was nearly always present during neuriti ... | 1984 | 6393607 |
| dna characterization of the spirochete that causes lyme disease. | lyme disease, a tick-borne disease long recognized in europe but only recently recognized in the united states, was shown in 1982-1983 to be caused by a spirochete, the lyme disease spirochete. whether one or more species of the spirochete exists is unknown, as is its taxonomic status. to answer these questions, we determined (i) the dna base (guanidine-plus-cytosine) content for five strains; (ii) the dna relatedness of 10 strains from europe or the united states (isolated from ticks, humans, a ... | 1984 | 6490812 |
| a borrelia-specific monoclonal antibody binds to a flagellar epitope. | in immunofluorescence assays monoclonal antibody h9724 recognized eight species of the spirochetal genus borrelia but not representatives of the genera treponema, leptospira, and spirochaeta. we examined the reactivity of h9724 against subcellular components of borrelia hermsii, an agent of relapsing fever, and b. burgdorferi, the cause of lyme disease. h9724 bound to isolated periplasmic flagella of the two borreliae. in western blots the antibody reacted with the predominant protein in flagell ... | 1986 | 3516878 |
| distribution of superoxide dismutase, catalase, and peroxidase activities among treponema pallidum and other spirochetes. | representative members of spirochaetales were surveyed for their content of superoxide dismutase (sod), catalase, and peroxidase activities. only leptospira exhibited peroxidase activity. obligately anaerobic cultivable treponema and spirochaeta possessed no sod or peroxidative capabilities. upon polyacrylamide gel electrophoresis, spirochaeta aurantia, borrelia hermsi, and five leptospira biflexa serovars showed sod activity associated with one electrophoretic band which was inhibited by h2o2, ... | 1981 | 7024127 |
| antigenic variation of borrelia hermsii. | at least 24 different serotypes were detected in populations of borrelia hermsii that originated from a single organism. these serotypes were identified by staining with specific fluoresceinated antisera prepared against cloned populations of living organisms of each type. in the order of decreasing frequency, the 10 types more often encountered were 7, which was clearly dominant, and 2, 17, 24, 13, 2, 1, 21, 11, and 12. each of the 24 types were shown to change to 7 or more other serotypes. spi ... | 1982 | 7130900 |
| functional activities of antibodies directed against surface lipoproteins of borrelia hermsii. | enriched preparations for mouse polyclonal immunoglobulin g (igg) antibodies reactive with surface-exposed epitopes (ab-see) of the 22-kda and 24-kda membrane lipoproteins of living borrelia hermsii (hs 1 strain) cells were obtained by an antibody absorption technique using living spirochetes. in vitro, the antibody preparations both inhibited spirochetal growth and were borreliacidal in the presence of complement. the monovalent fab antibody fragments, prepared from antibody-enriched preparatio ... | 1995 | 7494503 |
| biology of borrelia hermsii in kelly medium. | more than 800 borellia hermsii in mouse plasma were required for establishment of growth in an artificial medium (kelly), but only a single organism of a fully adapted strain (25th subculture) was required for a successful subculture. as judged by generation time, maximal concentration in culture, and length and motility of the organism, the process of adaptation extended through at least 11 subcultures. because the organisms regularly died shortly after the logarithmic growth phase, transfers a ... | 1974 | 4472988 |
| mechanisms of antigenic variation in borrelia hermsii and african trypanosomes. | | 1995 | 7713867 |
| borrelia burgdorferi binds plasminogen, resulting in enhanced penetration of endothelial monolayers. | several strains of borrelia burgdorferi and borrelia hermsii can bind human lys-plasminogen specifically. affinity blots using 125i-labeled plasminogen showed that numerous polypeptides of all the strains and species tested could bind via lysine residues to the plasminogen molecule since binding could be completely inhibited by the lysine analog epsilon-aminocaproic acid. binding analysis using 125i-labeled plasminogen on live intact organisms showed that the organisms possess two binding sites ... | 1995 | 7790059 |
| phenotypic analysis of outer surface protein c (ospc) of borrelia burgdorferi sensu lato by monoclonal antibodies: relationship to genospecies and ospa serotype. | molecular analyses of the genes encoding ospc, a major immunodominant protein of borrelia burgdorferi sensu lato, revealed a considerable degree of heterogeneity. in the present study, we investigated whether a similar heterogeneity of the ospc phenotype can be shown by analysis with monoclonal antibodies (mabs). thirteen ospc-specific mabs (l22 mabs) were produced by immunizing mice with either different combinations of whole-cell antigens or recombinantly expressed ospcs cloned from strains be ... | 1995 | 7699024 |
| activation of a vmp pseudogene in borrelia hermsii: an alternate mechanism of antigenic variation during relapsing fever. | the relapsing fever agent, borrelia hermsii, undergoes multiphasic antigenic variation to evade its host's immune response. a frequently observed switch is serotype 7 to 26. unlike silent vmp genes previously characterized, the transcriptionally silent vmp26 sequence was a pseudogene in lacking a start codon. in serotype 7 the location of the silent vmp26 sequence just downstream of vmp7 on the expression plasmid, as well as on the silent plasmid, was also unique. the demonstration of a predicte ... | 1994 | 7984108 |
| structural analysis of the variable major proteins of borrelia hermsii. | borrelia hermsii undergoes spontaneous antigenic variation in vivo and in vitro. serotype specificity is associated with expression of one of a family of molecular weight-variable proteins, the pi proteins. we studied the structure of the pi proteins as well as the molecular weight-invariable pii proteins of three serotypes of b. hermsii hs1: c, 7, and 21. the techniques used were one-dimensional (1-d) mapping of staphylococcus aureus v8 protease-generated peptides and two-dimensional (2-d) mapp ... | 1983 | 6644241 |
| 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 ... | 1995 | 7547303 |
| variable major proteins of borrellia hermsii. | borrelia hermsii, a relapsing fever agent, manifests antigenic variation in vivo and in vitro. we studied three mouse-passaged serotypes of strain hs1 (7, 14, and 21) and a hs1 derivative obtained after multiple in vitro passages (c serotype). all four serotypes had two major proteins in whole cell lysates fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. one major protein species (pii) had the same apparent subunit molecular weight (or approximately 3.9 x 10(4) in all t ... | 1982 | 7130901 |
| action of penicillin on borrelia hermsii. | borrelia hermsii, a spirochete and an etiological agent of relapsing fever, was cultivated in modified kelly medium. studies of the action of penicillin on b. hermsii strain hs1 revealed the following: (i) the in vitro minimum inhibitory concentration and minimum bactericidal concentration of benzylpenicillin for this strain were 0.4 and 3.1 nmol/ml (0.15 and 1.1 micrograms/ml), respectively; (ii) the primary morphological responses at the minimum bactericidal concentration of benzylpenicillin w ... | 1982 | 7103461 |
| interaction of borrelia spirochetes with human mononuclear leukocytes causes production of leukocytic pyrogen and thromboplastin. | relapsing fever caused by borrelia spirochetes is characterized by episodes of spirochetemia, fever, and dic. we examined the ability of borrelia hermsii to induce production of leukocytic pyrogen and thromboplastin from human blood leukocytes in vitro. organisms were found devoid of endotoxin by the limulus assay. human peripheral blood leukocytes were separated into mnc and pmn fractions and were incubated with two to five spirochetes per cell in 10% human serum. supernatant fluids from mnc-sp ... | 1982 | 7069269 |
| in vitro inhibition of borrelia burgdorferi growth by antibodies. | function-oriented immunoassays, such as complement fixation and neutralization, are not commonly used in the study of the lyme disease agent, borrelia burgdorferi. to determine whether such assays provide information additional to matrix-based methods, such as elisa, polyclonal antisera and monoclonal antibodies were examined for their abilities to agglutinate viable borreliae and inhibit their in vitro growth in microtiter plates. different strains of b. burgdorferi in both high and low passage ... | 1993 | 8418163 |
| opsonization of treponema pallidum is mediated by immunoglobulin g antibodies induced only by pathogenic treponemes. | rabbit antisera to leptospira interrogans, borrelia hermsii, and treponema phagedenis biotype reiter, reactive to shared spirochetal antigens, failed to enhance phagocytosis of treponema pallidum by macrophages, while immunoglobulin g to treponema pallidum subsp. pertenue and treponema paraluiscuniculi promoted phagocytosis. opsonic antibodies are directed to pathogen-restricted, not shared spirochetal, antigens. | 1993 | 8423106 |
| comparative study of the enzyme activities of borrelia burgdorferi and other non-intestinal and intestinal spirochaetes. | comparative analysis of the enzymatic profiles of 58 spirochaetal isolates clearly differentiated borrelias from leptospires, serpulinas and a treponeme. strains of both borrelia burgdorferi and borrelia hermsii characteristically produced significant amounts of leucine arylamidase. this enzyme activity was not unique to borrelias but was also detected amongst pathogenic and non-pathogenic leptospira serovars. this fact, however, did not hamper a correct differentiation of borrelias from these s ... | 1995 | 7760753 |
| antibody response in lyme disease: evaluation of diagnostic tests. | the antibody response to the ixodes dammini spirochete was determined in 41 serial serum samples from 12 patients with lyme disease. by enzyme-linked immunosorbent assay (elisa), 11 of the 12 patients had higher titers of specific igm antibody (greater than 1:200) during early disease than did 40 control subjects. specific igm antibody titers, which correlated with total amounts of igm antibody (p less than .001), sometimes remained elevated throughout the illness. during neuritis, nine of 10 pa ... | 1984 | 6373966 |
| standardization of medium for culturing lyme disease spirochetes. | to standardize the procedure for isolating and culturing lyme disease spirochetes, we modified the composition of the medium generally used for this purpose (bsk-ii) and developed a system for its distribution. this medium contains no gelatin or agarose, and various components are used in proportions that differ from those in bsk-ii. each of the major proteinacious components was screened by substitution in samples of the complete product. the final medium was evaluated for the capacity to grow ... | 1993 | 8501226 |
| experimental infection of the mouse brain by a relapsing fever borrelia species: a molecular analysis. | the spirochetal disease relapsing fever is notable not only for multiphasic antigenic variation but also for central neurologic manifestations. to further characterize involvement of the brain in this disorder, immunocompetent and -deficient mice were infected with borrelia hermsii. immunodeficient mice were treated while spirochetemic with neutralizing igm monoclonal antibodies to the infecting serotype. blood, cerebrospinal fluid, and brain tissue were examined by culture and polymerase chain ... | 1993 | 8515101 |
| in vitro activity of vancomycin against the spirochete borrelia burgdorferi. | borrelia burgdorferi, a spirochete and the causative agent of lyme disease, has been reported to be susceptible to a variety of antimicrobial agents. in this investigation, the action of vancomycin, a glycopeptide antibiotic not previously known to have activity against spirochetes, against borrelias was examined. the in vitro activity of vancomycin against a variety of strains of b. burgdorferi and one strain of borrelia hermsii was determined by use of a microdilution mic method (l.l. dever, j ... | 1993 | 8517700 |
| transposition of structural genes to an expression sequence on a linear plasmid causes antigenic variation in the bacterium borrelia hermsii. | in borrelia hermsii, a spirochaete that causes relapsing fever, the switch between expression of two frequent variable major protein (vmp) types (7 and 21) is associated with a dna rearrangement. both cell types 7 and 21 contain untranscribed 7 and 21 vmp genes on linear plasmids. the serotype 7 cells contain an additional copy of the 7 vmp gene fused to an expression sequence on another linear plasmid. switching to the 21 serotype involves removal of the transcribed 7 vmp gene and fusion of a c ... | 1985 | 4069202 |
| involvement of birds in the epidemiology of the lyme disease agent borrelia burgdorferi. | borrelia burgdorferi, the causative agent of lyme disease, was isolated from the liver of a passerine bird, catharus fuscescens (veery), and from larval ixodes dammini (tick) feeding on pheucticus ludovicianus (rose-breasted grosbeak) and geothlypis trichas (common yellowthroat). in indirect immunofluorescence antibody tests, isolates reacted with polyclonal and monoclonal (h5332) antibodies. studies on the dna composition of the veery liver isolate and the strain cultured from an i. dammini lar ... | 1986 | 3943893 |
| tick-borne relapsing fever due to borrelia hermsii in british columbia. | | 1986 | 3940604 |
| homology of variable major protein genes between borrelia hermsii and borrelia miyamotoi. | antigenic variation has been studied in detail for the etiological agent of relapsing fever, borrelia hermsii. the variable major proteins (vmps) are found at its cell surface, enabling it to avoid the host's immune response. we have cloned and sequenced the vmp-gene (vmp)-like sequences from the borrelia miyamotoi strains ht31 and fr64b and the deduced amino acid sequences were compared with the published vmp proteins vmp3, vmp24, and vmp33 of b. hermsii. the sequences were aligned and revealed ... | 1996 | 8764474 |
| genetic analysis of borrelia. | dna homology studies were performed on borrelia hermsii, b. duttoni, b. crocidurae and the o. coriaceus spirochete. these organisms had a genus level relationship with each other. b. hermsii was 17 to 53% homologous with b. duttoni, b. crocidurae, and the o. coriaceus spirochetes; b. crocidurae was 17-32% related to b. hermsii, b. anserina and the o. coriaceus spirochete, and the o. coriaceus spirochete was 28-50% related to b. hermsii, b. crocidurae and b. anserina. the o. coriaceus spirochete ... | 1986 | 3577474 |
| antigenic variation among borrelia spp. in relapsing fever. | seven antigens of borrelia hermsii, b. parkeri, and b. turicatae with isoelectric points in the range of 4.4 to 5.0 and molecular masses of 40 to 43 kilodaltons played a role in the relapse phenomenon of relapsing fever. based upon location of the antigens in the outer envelope, the molecular weight, and western blot analysis, the antigens from each phase of spirochetemia appeared to be a mixture of the serotype-specific antigens of cloned b. hermsii. | 1986 | 3536750 |
| cultivation of borrelia hermsi. | a medium has been developed which permits the isolation and growth of borrelia hermsi, an organism that causes relapsing fever. | 1971 | 5557322 |
| variable major proteins of borrelia hermsii. epitope mapping and partial sequence analysis of cnbr peptides. | the variable major proteins (vmp) of serotypes 7 and 21 of the relapsing fever agent borrelia hermsii were isolated by detergent extraction and high performance liquid chromatography. cyanogen bromide (cnbr) digestion of the isolated vmp yielded two peptides of apparent molecular weights 20,000 (20 k) and 16 k from vmp7, and three peptides of 14.5, 14, and 7 k mol wt from vmp21. serotype-specific monoclonal antibodies bound in western blots to one of each of the two or three cnbr fragments from ... | 1985 | 2409197 |
| juxtaposition of expressed variable antigen genes with a conserved telomere in the bacterium borrelia hermsii. | borrelia hermsii, an agent of relapsing fever, survives in mammals through antigenic variation. change in serotype-specific variable outer membrane proteins (vmps) occurs when a vmp gene at an expression site is replaced with a previously silent gene for another vmp. silent and active genes are on separate linear plasmids. the upstream site for a nonreciprocal recombination between two linear plasmids is near the 5' ends of the expressed and silent genes. in the present study we sought the downs ... | 1990 | 2385585 |
| the bacterial nucleoid visualized by fluorescence microscopy of cells lysed within agarose: comparison of escherichia coli and spirochetes of the genus borrelia. | the nucleoids of escherichia coli and the spirochetes borrelia burgdorferi and borrelia hermsii, agents of lyme disease and relapsing fever, were examined by epifluorescence microscopy of bacterial cells embedded in agarose and lysed in situ with detergent and protease. the typical e. coli nucleoid was a rosette in which 20 to 50 long loops of dna emanated from a dense node of dna. the percentages of cells in a population having nucleoids with zero, one, two, and three nodes varied with growth r ... | 1997 | 9079908 |
| sequence analysis and characterization of a 40-kilodalton borrelia hermsii glycerophosphodiester phosphodiesterase homolog. | we report the purification, molecular cloning, and characterization of a 40-kda glycerophosphodiester phosphodiesterase homolog from borrelia hermsii. the 40-kda protein was solubilized from whole organisms with 0.1% triton x-100, phase partitioned into the triton x-114 detergent phase, and purified by fast-performance liquid chromatography (fplc). the gene encoding the 40-kda protein was cloned from a b. hermsii chromosomal dna lambda exlox expression library and identified by using affinity an ... | 1997 | 9079909 |
| variable antigen genes of the relapsing fever agent borrelia hermsii are activated by promoter addition. | borrelia hermsii, an agent of relapsing fever, avoids the host's immune response by means of multiphasic antigenic variation. serotype specificity is determined by variable antigens called the vmp lipoproteins. through recombination between linear plasmids a formerly silent vmp gene replaces another vmp gene at a telomeric expression locus. we examined strain hs1 borreliae before and after a switch from serotype 7 to serotype 21. the nucleotide sequences of 5' regions of silent and expressed vmp ... | 1991 | 2041480 |
| borrelia burgdorferi dna and borrelia hermsii dna are not associated with morphea or lichen sclerosus et atrophicus in the southwestern united states. | | 1997 | 9301604 |
| identification of the treponema pallidum subsp. pallidum glycerophosphodiester phosphodiesterase homologue. | to identify potential opsonic targets of treponema pallidum subsp. pallidum, a treponemal genomic expression library was constructed and differentially screened with opsonic and non-opsonic t. pallidum antisera. this method identified an immunoreactive clone containing an open reading frame encoding a 356 residue protein. nucleotide sequence analysis demonstrated the translated protein to be a homologue of glycerophosphodiester phosphodiesterase, a glycerol metabolizing enzyme previously identif ... | 1997 | 9311129 |
| 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 ... | 1997 | 9336893 |
| the variable antigens vmp7 and vmp21 of the relapsing fever bacterium borrelia hermsii are structurally analogous to the vsg proteins of the african trypanosome. | the relapsing fever agent borrelia hermsii avoids the host's immune response by the strategy of multiphasic antigenic variation. a given borrelia cell can express one of a number of alleles for polymorphic outer-membrane proteins, known as vmp proteins. the genes for the variant-specific vmp proteins of serotypes 7 and 21 of b. hermsii strain hs1 were sequenced. the genes, which were designated vmp7 and vmp21, were obtained from populations of borreliae before and after a switch in serotypes fro ... | 1990 | 1706456 |
| immunodominant major outer membrane proteins of ehrlichia chaffeensis are encoded by a polymorphic multigene family. | several immunodominant major proteins ranging from 23 to 30 kda were identified in the outer membrane fractions of ehrlichia chaffeensis and ehrlichia canis. the n-terminal amino acid sequence of a 28-kda protein of e. chaffeensis (one of the major proteins) was determined. the gene (p28), almost full length, encoding the 28-kda protein was cloned by pcr with primers designed based on the n-terminal sequence of the e. chaffeensis 28-kda protein and the consensus sequence between the c termini of ... | 1998 | 9423849 |
| subtelomeric expression regions of borrelia hermsii linear plasmids are highly polymorphic. | borrelia hermsii, a relapsing fever agent, undergoes multiphasic antigenic variation to evade its host's immune response. serotype specificity is determined by variable membrane lipoproteins, vmps, which are expressed from genes located near the end of a linear plasmid. using the polymerase chain reaction and primers representing the promoter of the active vmp and a conserved telomeric sequence, we characterized the subtelomeric expression regions of the 25 known serotypes of strain hs1. the dis ... | 1992 | 1484486 |
| population structure of the relapsing fever spirochete borrelia hermsii as indicated by polymorphism of two multigene families that encode immunogenic outer surface lipoproteins. | the tick-borne relapsing fever spirochete borrelia hermsii evades the mammalian immune system by periodically switching expression among members of two multigene families that encode immunogenic, antigenically distinct outer surface proteins. the type strain, b. hermsii hs1, has at least 40 complete genes and pseudogenes that participate in this multiphasic antigenic variation. originally termed vmp (for variable major protein) genes, they have been reclassified as vsp (for variable small protei ... | 1998 | 9453591 |
| the spirochete borrelia crocidurae causes erythrocyte rosetting during relapsing fever. | several species of the genus borrelia exhibit antigenic variation of variable major proteins on their surface during relapsing fever. we have investigated the african relapsing fever species borrelia crocidurae during infections in mice and compared it with the thoroughly studied north american species borrelia hermsii. a major difference between the two species is that b. crocidurae can bind and become completely covered with erythrocytes. in addition, b. crocidurae causes a prolonged spirochet ... | 1998 | 9453646 |
| 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 ... | 1998 | 9488399 |
| analysis of the organization of multicopy linear- and circular-plasmid-carried open reading frames in borrelia burgdorferi sensu lato isolates. | plasmid cp8.3 of borrelia afzelii ip21 carries several open reading frames (orfs) and a 184-bp inverted repeat (ir) element. it has been speculated that this plasmid may encode factors involved in virulence or infectivity. in this report, we have characterized the distribution, molecular variability, and organization of orfs 1, 2, and 4 and the ir elements among isolates of the borrelia burgdorferi sensu lato complex. orfs 1 and 2 are contained within a segment of cp8.3 that is bordered by the i ... | 1998 | 9488408 |
| 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 ... | 1998 | 9537355 |
| structure and expression of the flaa periplasmic flagellar protein of borrelia burgdorferi. | the spirochete which causes lyme disease, borrelia burgdorferi, has many features common to other spirochete species. outermost is a membrane sheath, and within this sheath are the cell cylinder and periplasmic flagella (pfs). the pfs are subterminally attached to the cell cylinder and overlap in the center of the cell. most descriptions of the b. burgdorferi flagellar filaments indicate that these organelles consist of only one flagellin protein (flab). in contrast, the pfs from other spirochet ... | 1998 | 9573194 |
| molecular characterization of mycoplasma arthritidis variable surface protein maa2. | earlier studies implied a role for mycoplasma arthritidis surface protein maa2 in cytadherence and virulence and showed that it exhibited both size and phase variability. here we report the further analysis of maa2 and the cloning and sequencing of the maa2 gene from two m. arthritidis strains, 158p10p9 and h606, expressing two size variants of maa2. triton x-114 partitioning and metabolic labeling with [3h]palmitic acid suggested lipid modification of maa2. surface exposure of the c terminus wa ... | 1998 | 9596719 |
| incorporation of cysteine by borrelia burgdorferi and borrelia hermsii. | the growth rate of borrelia burgdorferi and borrelia hermsii in bsk ii medium prepared with cysteine-free or cysteine-containing (0.185-5.92 mm) cmrl 1066 medium was studied. in media with cysteine-free cmrl 1066, growth of borreliae was detectable, although it was reduced by approximately 80%. bacterial growth was maximal when the concentration of cysteine in cmrl 1066 reached 1.48 mm, which represents the standard cysteine concentrations of the medium; higher concentrations inhibited the growt ... | 1992 | 1477785 |
| the relapsing fever agent borrelia hermsii has multiple copies of its chromosome and linear plasmids. | borrelia hermsii, a spirochete which causes relapsing fever in humans and other mammals, eludes the immune response by antigenic variation of the "vmp" proteins. this occurs by replacement of an expressed vmp gene with a copy of a silent vmp gene. silent and expressed vmp genes are located on separate linear plasmids. to further characterize vmp recombination, copy numbers were determined for two linear plasmids and for the 1-megabase chromosome by comparing hybridization of probes to native dna ... | 1992 | 1427031 |
| characterization of serologically nontypeable actinobacillus actinomycetemcomitans isolates. | our previous studies have shown that actinobacillus actinomycetemcomitans isolates of a given arbitrarily primed pcr (ap-pcr) genotype belong to the same serotype (of serotypes a through e). in the present study we investigated whether the ap-pcr genotypes of nonserotypeable a. actinomycetemcomitans isolates match those of the serotypeable isolates. the isolates were additionally characterized by restriction analysis of the apah pcr amplification products. the material included 75 nonserotypeabl ... | 1998 | 9650954 |
| in vitro antimicrobial susceptibility testing of borrelia burgdorferi: a microdilution mic method and time-kill studies. | the susceptibility of borrelia burgdorferi, the causative agent of lyme borreliosis, to various antimicrobial agents varies widely among published studies. these differences are probably due in part to variations in susceptibility testing techniques and growth endpoint determinations. we developed a microdilution method for determining the mics of antibiotics against b. burgdorferi. the method incorporated bsk ii medium, a final inoculum of 10(6) cells per ml, and a 72-h incubation period and wa ... | 1992 | 1400969 |
| relapsing fever and its serological discrimination from lyme borreliosis. | patients with borrelia-caused relapsing fever produce cross-reacting antibodies to borrelia burgdorferi, the anti-genetically related causative agent of lyme borreliosis. the antibody response of the serum of a patient (acute and convalescent) with relapsing fever was analysed by the immunoblot technique using borrelia hermsii and b. burgdorferi as antigens. the diagnosis was established by microscopic detection of spirochetes in the patient's blood. the patient's serum showed significantly elev ... | 1992 | 1385332 |
| evolution of the borrelia burgdorferi outer surface protein ospc. | the genes coding for outer surface protein ospc from 22 borrelia burgdorferi strains isolated from patients with lyme borreliosis were cloned and sequenced. for reference purposes, the 16s rrna genes from 17 of these strains were sequenced after being cloned. the deduced ospc amino acid sequences were aligned with 12 published ospc sequences and revealed the presence of 48 conserved amino acids. on the basis of the alignment, ospc could be divided into an amino-terminal relatively conserved regi ... | 1995 | 7768799 |
| plasmid location of borrelia purine biosynthesis gene homologs. | the lyme disease spirochete borrelia burgdorferi must survive in both its tick vector and its mammalian host to be maintained in nature. we have identified the b. burgdorferi guaa gene encoding gmp synthetase, an enzyme involved in de novo purine biosynthesis that is important for the survival of bacteria in mammalian blood. this gene encodes a functional product that will complement an escherichia coli gmp synthetase mutant. the gene is located on a 26-kb circular plasmid, adjacent to and diver ... | 1994 | 7961392 |
| a family of surface-exposed proteins of 20 kilodaltons in the genus borrelia. | relapsing fever and lyme disease spirochetes of the genus borrelia display at their surfaces abundant lipoproteins: vmp proteins in borrelia hermsii and osp proteins in borrelia burgdorferi. vmp and osp proteins largely determine serotype specificity, and neutralizing antibodies of infected or immunized animals are directed at them. for the present study, we examined b. hermsii serotype 33, which is unique among strain hs1 serotypes in the low frequency of switches to other serotypes during infe ... | 1994 | 8005669 |
| differential association of borrelia species with cultured neural cells. | studies of the interactions of relapsing fever borrelia species with cultured neural cells have not been reported. in the present work, the interaction of the relapsing fever agents borrelia hermsii and borrelia turicatae with cultured neural and endothelial cells was studied and compared with borrelia burgdorferi, the agent of lyme disease. all borrelia species bound each cell type tested. host cell association was time-dependent and saturable. with the exception of human neuron cells, b. herms ... | 1994 | 8106781 |
| homology between borrelia burgdorferi ospc and members of the family of borrelia hermsii variable major proteins. | synthesis of the borrelia burgdorferi outer surface protein c (ospc) is quite variable. we have cloned and sequenced the ospc gene from b. burgdorferi isolate ca-11.2a, a clone in which ospc expression varies. the 5' flanking region of the gene contains at least two consensus promoter regions, as well as two large overlapping inverted repeats. sequence comparison to other ospc proteins indicated that the ca-11.2a ospc is as closely related to ospc from two different genospecies of lyme disease s ... | 1994 | 8200524 |
| function and protective capacity of treponema pallidum subsp. pallidum glycerophosphodiester phosphodiesterase. | infectious syphilis, caused by the spirochete bacterium treponema pallidum subsp. pallidum, remains a public health concern worldwide. the immune-response evasion mechanisms employed by t. pallidum are poorly understood, and prior attempts to identify immunoprotective antigens for subsequent vaccine design have been unsuccessful. previous investigations conducted in our laboratory identified the t. pallidum glycerophosphodiester phosphodiesterase as a potential immunoprotective antigen by using ... | 1998 | 9826352 |
| treponema pallidum major sheath protein homologue tpr k is a target of opsonic antibody and the protective immune response. | we have identified a family of genes that code for targets for opsonic antibody and protective immunity in t. pallidum subspecies pallidum using two different approaches, subtraction hybridization and differential immunologic screening of a t. pallidum genomic library. both approaches led to the identification of a polymorphic multicopy gene family with predicted amino acid homology to the major sheath protein of treponema denticola. one of the members of this gene family, tpr k, codes for a pro ... | 1999 | 9989979 |
| 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. | 1993 | 8285697 |
| isolation and characterization of borrelia burgdorferi from blood of a bird captured in the saint croix river valley. | field investigations were conducted to further evaluate the role of birds in the maintenance and dissemination of borrelia burgdorferi. blood specimens were taken from 39 passerine birds of 17 species captured during june 1991 at the saint croix national riverway in wisconsin, and one isolate, wi91-23, was cultured from an adult song sparrow (melospiza melodia). this isolate was shown to be infectious for peromyscus leucopus and mesocricetus auratus (golden hamster). isolate wi91-23 was confirme ... | 1993 | 8370728 |
| opsonic requirements for phagocytosis of borrelia hermsii by human polymorphonuclear leukocytes. | opsonic requirements for phagocytosis by human polymorphonuclear leukocytes (pmnls) of a laboratory strain of borrelia hermsii were examined. intracellular localization of spirochetes was confirmed by electron microscopy and cinephotomicroscopy. phagocytosis of 3h-labeled spirochetes was increased with higher concentrations of pooled human serum or greater ratios of spirochetes to pmnls and was unaffected by diminished classical complement pathway activity. immune rabbit serum markedly increased ... | 1982 | 7061882 |
| segmented arrangement of borrelia duttonii dna and location of variant surface antigen genes. | the dna of an isolate of borrelia duttonii, an agent of relapsing fever is present as seven major species ranging in size from 10 kb to greater than 150 kb. additionally, this isolate contains low copy number species, both smaller and larger than these seven major elements. no one of these individual dna species obviously corresponds to the bacterial chromosome, unlike the situation in borrelia hermsii, another relapsing fever borrelia. thus it appears that b. duttonii has a unique segmented arr ... | 1988 | 3246585 |
| intragenic recombination and a chimeric outer membrane protein in the relapsing fever agent borrelia hermsii. | the spirochete borrelia hermsii, a relapsing fever agent, evades the host's immune response through multiphasic antigenic variation. antigen switching results from sequential expression of genes for serotype-specific outer membrane proteins known as variable major proteins (vmp's); of the 25 serotypes that have been identified for the hs1 strain, serotypes 7 and 21 have been studied in greatest detail. in the present study, an atypical variant was predominant in the relapse from a serotype 21 in ... | 1993 | 7683020 |
| restriction of major surface protein 2 (msp2) variants during tick transmission of the ehrlichia anaplasma marginale. | anaplasma marginale is an ehrlichial pathogen of cattle that establishes lifelong persistent infection. persistence is characterized by rickettsemic cycles in which new a. marginale variant types, defined by the sequence of the expressed msp2 transcripts, emerge. the polymorphic msp2 transcripts encode structurally distinct msp2 proteins and result in an antigenically diverse and continually changing a. marginale population within the blood. in this manuscript, we used sequence analysis of msp2 ... | 1999 | 10077656 |
| 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 ... | 1993 | 8432812 |
| adherence of borrelia burgdorferi and borrelia hermsii to mammalian cells in vitro. | this study investigated the ability of borrelia burgdorferi and borrelia hermsii to attach the surface of several types of in vitro-cultured mammalian cells. borreliae showed different adhesion efficiencies depending on cell type and temperature. temperatures both lower and higher than 33 degrees and 37 degrees c respectively, decreased the adhesion of borreliae which preferentially adhere to human fibroblast-like cells. the adhesion process, mediated by structures exposed onto the surface of th ... | 1993 | 8469170 |
| membrane topology and cellular location of the treponema pallidum glycerophosphodiester phosphodiesterase (glpq) ortholog. | recent reports that isolated treponema pallidum outer membranes contain an ortholog for glycerophosphodiester phosphodiesterase (glpq) (d. v. shevchenko, d. r. akins, e. j. robinson, m. li, o. v. shevchenko, and j. d. radolf, infect. immun. 65:4179-4189, 1997) and that this protein is a potential opsonic target for t. pallidum (c. e. stebeck, j. m. shaffer, t. w. arroll, s. a. lukehart, and w. c. van voorhis, fems microbiol. lett. 154:303-310, 1997) prompted a more detailed investigation of its ... | 1999 | 10225883 |