Strain typing of Borrelia burgdorferi, Borrelia afzelii, and Borrelia garinii by using multiple-locus variable-number tandem repeat analysis.
(25/122)
Human Lyme borreliosis (LB) is the most prevalent arthropod-borne infection in temperate climate zones around the world and is caused by Borrelia spirochetes. We have identified 10 variable-number tandem repeat (VNTR) loci present within the genome of Borrelia burgdorferi and subsequently developed a multiple-locus VNTR analysis (MLVA) typing system for this disease agent. We report here the successful application of MLVA for strain discrimination among a group of 41 globally diverse Borrelia isolates including B. burgdorferi, B. afzelii, and B. garinii. PCR assays displayed diversity at these loci, with total allele numbers ranging from two to nine and Nei's diversity (D) values ranging from 0.10 to 0.87. The average D value was 0.53 across all VNTR loci. A clear correlation exists between the repeat copy number and the D value (r = 0.62) or the number of alleles (r = 0.93) observed across diverse strains. Cluster analysis by the unweighted pair-group method with arithmetic means resolved the 30 observed unique Borrelia genotypes into five distinct groups. B. burgdorferi, B. afzelii, and B. garinii clustered into distinct affiliations, consistent with current 16S rRNA phylogeny studies. Genetic similarity and diversity suggest that B. afzelii and B. garinii are close relatives and were perhaps recently derived from B. burgdorferi. MLVA provides both phylogenetic relationships and additional resolution to discriminate among strains of Borrelia species. This new level of strain identification and discrimination will allow more detailed epidemiological and phylogenetic analysis in future studies. (+info)
Detection of Borrelia lonestari, putative agent of southern tick-associated rash illness, in white-tailed deer (Odocoileus virginianus) from the southeastern United States.
(26/122)
To determine if white-tailed deer may serve as a reservoir host for Borrelia lonestari, we used a nested PCR for the Borrelia flagellin gene to evaluate blood samples collected from deer from eight southeastern states. Seven of 80 deer (8.7%) from 5 of 17 sites (29.4%) had sequence-confirmed evidence of a B. lonestari flagellin gene by PCR, indicating that deer are infected with B. lonestari or another closely related Borrelia species. Our findings expand the known geographic range of B. lonestari and provide the first evidence of this organism in a vertebrate other than humans. (+info)
Glycerol-3-phosphate acquisition in spirochetes: distribution and biological activity of glycerophosphodiester phosphodiesterase (GlpQ) among Borrelia species.
(27/122)
Relapsing-fever spirochetes achieve high cell densities (>10(8)/ml) in their host's blood, while Lyme disease spirochetes do not (<10(5)/ml). This striking contrast in pathogenicity of these two groups of bacteria suggests a fundamental difference in their ability to either exploit or survive in blood. Borrelia hermsii, a tick-borne relapsing-fever spirochete, contains orthologs to glpQ and glpT, genes that encode glycerophosphodiester phosphodiesterase (GlpQ) and glycerol-3-phosphate transporter (GlpT), respectively. In other bacteria, GlpQ hydrolyzes deacylated phospholipids to glycerol-3-phosphate (G3P) while GlpT transports G3P into the cytoplasm. Enzyme assays on 17 isolates of borreliae demonstrated GlpQ activity in relapsing-fever spirochetes but not in Lyme disease spirochetes. Southern blots demonstrated glpQ and glpT in all relapsing-fever spirochetes but not in the Lyme disease group. A Lyme disease spirochete, Borrelia burgdorferi, that was transformed with a shuttle vector containing glpTQ from B. hermsii produced active enzyme, which demonstrated the association of glpQ with the hydrolysis of phospholipids. Sequence analysis of B. hermsii identified glpF, glpK, and glpA, which encode the glycerol facilitator, glycerol kinase, and glycerol-3-phosphate dehydrogenase, respectively, all of which are present in B. burgdorferi. All spirochetes examined had gpsA, which encodes the enzyme that reduces dihydroxyacetone phosphate (DHAP) to G3P. Consequently, three pathways for the acquisition of G3P exist among borreliae: (i) hydrolysis of deacylated phospholipids, (ii) reduction of DHAP, and (iii) uptake and phosphorylation of glycerol. The unique ability of relapsing-fever spirochetes to hydrolyze phospholipids may contribute to their higher cell densities in blood than those of Lyme disease spirochetes. (+info)
Spirochete-platelet attachment and thrombocytopenia in murine relapsing fever borreliosis.
(28/122)
Thrombocytopenia is common in persons infected with relapsing fever Borreliae. We previously showed that the relapsing fever spirochete Borrelia hermsii binds to and activates human platelets in vitro and that, after platelet activation, high-level spirochete-platelet attachment is mediated by integrin alpha IIb beta 3, a receptor that requires platelet activation for full function. Here we established that B hermsii infection of the mouse results in severe thrombocytopenia and a functional defect in hemostasis caused by accelerated platelet loss. Disseminated intravascular coagulation, immune thrombocytopenic purpura, or splenic sequestration did not play a discernible role in this model. Instead, spirochete-platelet complexes were detected in the blood of infected mice, suggesting that platelet attachment by bacteria might result in platelet clearance. Consistent with this, splenomegaly and thrombocytopenia temporally correlated with spirochetemia, and the severity of thrombocytopenia directly correlated with the degree of spirochetemia. Activation of platelets and integrin alpha IIb beta 3 were apparently not required for bacterium-platelet binding or platelet clearance because the bacterium-bound platelets in the circulation were not activated, and platelet binding and thrombocytopenia during infection of beta 3-deficient and wild-type mice were indistinguishable. These findings suggest that thrombocytopenia of relapsing fever is the result of platelet clearance after beta 3-independent bacterial attachment to circulating platelets. (+info)
Analysis of the ability of spirochete species associated with relapsing fever, avian borreliosis, and epizootic bovine abortion to bind factor H and cleave c3b.
(29/122)
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 pathogenesis of the relapsing-fever spirochetes. (+info)
ISOLATION OF BORRELIA REFRINGENS IN PURE CULTURE FROM PATIENTS WITH CONDYLOMATA ACUMINATA.
(30/122)
Hanson, Albert W. (Communicable Disease Center, Atlanta, Ga.), and George R. Cannefax. Isolation of Borrelia refringens in pure culture from patients with condylomata acuminata. J. Bacteriol. 88:111-113. 1964.-Borrelia refringens was isolated from five of ten clinical specimens by use of a modification of the Noguchi technique. An enriched anaerobic medium is described for the cultivation of B. refringens with retention of morphological characteristics. (+info)
Dropped head syndrome in mitochondriopathy.
(31/122)
In a 63-year-old, 165-cm-tall woman with a history of repeated tick bites, dilative cardiomyopathy, osteoporosis, progressive head ptosis with neck stiffness and cervical pain developed. The family history was positive for thyroid dysfunction and neuromuscular disorders. Neurological examination revealed prominent forward head drop, weak anteflexion and retroflexion, nuchal rigidity, weakness of the shoulder girdle, cogwheel rigidity, and tetraspasticity. The lactate stress test was abnormal. Electromyograms of various muscles were myogenic. Muscle biopsy showed non-specific myogenic abnormalities and generally weak staining for cytochrome oxydase. Mitochondriopathy with multi-organ involvement was suspected. The response to anti-Parkinson medication was poor. In conclusion, dropped head syndrome (DHS) may be due to multi-organ mitochondriopathy, manifesting as Parkinsonism, tetraspasticity, dilative cardiomyopathy, osteoporosis, short stature, and myopathy. Anti-Parkinson medication is of limited effect. (+info)
First culture isolation of Borrelia lonestari, putative agent of southern tick-associated rash illness.
(32/122)
Southern tick-associated rash illness (STARI) is a Lyme disease-like infection described in patients in the southeastern and south-central United States, where classic Lyme disease is relatively rare. STARI develops following the bite of a lone star tick (Amblyomma americanum) and is thought to be caused by infection with an "uncultivable" spirochete tentatively named Borrelia lonestari. In this study, wild lone star ticks collected from an area where B. lonestari is endemic were cocultured in an established embryonic tick cell line (ISE6). The cultures were examined by dark-field microscopy for evidence of infection, and spirochete identity and morphology were evaluated by flagellin B and 16S rRNA gene sequence, by reaction to Borrelia-wide and B. burgdorferi-specific monoclonal antibodies, and by electron microscopy. Live spirochetes were first visualized in primary culture of A. americanum ticks by dark-field microscopy 14 days after the cell culture was inoculated. The sequences of the flagellin B and 16S rRNA genes of cultured spirochetes were consistent with previously reported sequences of B. lonestari. The cultured spirochetes reacted with a Borrelia-wide flagellin antibody, but did not react with an OspA antibody specific to B. burgdorferi, by indirect fluorescent antibody testing. Electron microscopy demonstrated organisms that were free and associated with ISE6 cells, with characteristic Borrelia sp. morphology. This study describes the first successful isolation of B. lonestari in culture, providing a much needed source of organisms for the development of diagnostic assays and forming a basis for future studies investigating the role of the organism as a human disease agent. (+info)