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 Co53, B. burgdorferi sensu stricto strain CA4, and the relapsing-fever spirochete B. parkeri (undesignated). The 16S rRNA region of CA434 and CA435 differed from that of B. coriaceae type strain Co53 by the presence of 1 base (C) at position 367 (GenBank accession no. U42286). The linear plasmid profile of CA434 was similar to that of Co53, and the ApaI, BamHI, and HindIII restriction fingerprints of the total cellular DNA of CA434 and Co53 were similar. In contrast, CA435 differed somewhat from CA434 and Co53, which demonstrates that B. coriaceae is genetically diverse. Southern hybridization showed that the DNAs of CA434 and CA435 hybridized strongly with the digoxigenin-labeled DNA of Co53. Low homology was found between the DNA of Co53 and that of B. parkeri. The 16S rRNA sequence of B. parkeri was identical to previously published results for B. parkeri strain M3001 (GenBank accession number U42296). CA434 and CA435 represent only the second and third isolates of B. coriaceae obtained from any source since its initial isolation from an O. coriaceus tick in 1985. All three B. coriaceae isolates were derived from adult ticks collected from the same locality in northwestern California. Difficulties encountered in detecting B. coriaceae in, and isolating this spirochete from, the tissues of O. coriaceus are discussed. The lack of concordance between different detection or isolation methods suggests that reliance upon a single technique may grossly underestimate the true prevalence of spirochetal infection in wild-caught O. coriaceus ticks.     

Use of polymerase chain reaction and specific monoclonal antibodies as rapid method to recognize Borrelia burgdorferi sensu stricto,B. garinii and B. afzelii among Italian isolates of B. burgdorferi

We previously classified locally isolated strains of Borrelia burgdorferi by a restriction fragment length polymorphism analysis of total DNA, by DNA/DNA Southern Blot hybridization and by a hybridization with rRNA 16 + 23 S from Escherichia coli [Cinco et al. (1993) Microbiologica 16:323–332] into three genetic groups which, according to the reference strains used, should correspond to the three species so far described as B. burgdorferi sensu stricto, B. garinii and B. afzelii. To find a simpler method for strain identification, in this study we analyzed the Italian strains and some strains identification, in this study we analyzed the Italian strains and some strains originating from other European countries, employing the species-specific 16S rRNA primers in the polymerase chain reaction technique (PCR) and some phenotypic markers like the B. afzelii-specific monoclonal antibodies and the battery of OspA-specific monoclonal antibodies which were reported to give a reactivity pattern correlated to the species [Wilske et al. (1993) J Clin Microbiol 31:340–350]. The PCR results confirmed those obtained previously by identifying the three groups as B. burgdorferi sensu stricto, B. garinii and B. afzelii; the reactivity patterns obtained with the monoclonal antibodies (mAb) also corresponded to those described as typical of the three species. We standardized the PCR technique to amplify a sample of crude template DNA obtained from a culture of 10⁵ spirochetes.     

Identification of three clinically relevant Borrelia burgdorferi sensu lato genospecies by PCR-restriction fragment length polymorphism analysis of 16S-23S ribosomal DNA spacer amplicons

We report the results of a study of the prevalences of three clinically relevant Borrelia burgdorferi sensu lato genospecies (Borrelia burgdorferi sensu stricto, Borrelia afzelii, and Borrelia garinii) in 1,040 questing Ixodes ticks from all regions of Latvia, where Lyme borreliosis is endemic. The prevalences of Borrelia in Ixodes ricinus and Ixodes persulcatus were 22.6 and 27.9%, respectively. Molecular typing of B. burgdorferi from infected ticks was performed by restriction fragment length polymorphism (RFLP) analysis of PCR-amplified fragments of the 16S-23S (rrs-rrlA) rRNA intergenic spacer by using species-specific primers and subsequent sequencing. The dominant Borrelia species in both Ixodes species was B. afzelii. In addition, different restriction patterns of B. garinii and B. afzelii were also identified. This study demonstrates that the 16S-23S rRNA PCR-RFLP typing method is simple, sensitive, and fast and that it allows one to differentiate among B. burgdorferi species and subspecies with various degrees of pathogenic potential directly in ticks. These features are important in monitoring Lyme disease.     

Determination of novel Borrelia genospecies in Swedish Ixodes ricinus ticks

A total of 301 adult questing Ixodes ricinus ticks were collected at 15 different locations along the south and east coasts of Sweden to determine the Borrelia genospecies diversity. Thirty-two ticks (11%) were found to be positive by nested PCR with Borrelia burgdorferi sensu lato-specific primers. Species determination was based on partial sequencing of the 16S rRNA gene and the flagellin gene. Five different Borrelia species were found. The nucleotide sequence of the Borrelia DNA found in two ticks differed extensively from the nucleotide sequences of the Borrelia DNA found in the other ticks, and analysis revealed that they were closely related to the relapsing fever borrelia species Borrelia miyamotoi. This is the first report of a B. miyamotoi-like borrelia in I. ricinus and in Europe. Moreover, the Borrelia DNA of two ticks (6%) clustered within the B. valaisiana complex. B. valaisiana has not previously been reported in Sweden. B. afzelii DNA was found in 14 ticks (44%), and B. garinii DNA was found in 10 ticks (31%). B. burgdorferi sensu stricto DNA was found in four ticks (13%). We conclude that all of the known human-pathogenic species (B. garinii, B. afzelii, and B. burgdorferi sensu stricto) and B. valaisiana found elsewhere in Europe are also present in the Swedish host-seeking tick population and that a B. miyamotoi-like Borrelia species seems to be present in I. ricinus ticks in Europe.     

Characterization of Borrelia burgdorferi isolates by restriction endonuclease analysis and DNA hybridization.

Genomes of several Borrelia burgdorferi isolates from North America and Europe were characterized by restriction endonuclease analysis and DNA hybridization using labeled B. burgdorferi whole-cell DNA (strain ATCC 35210). Several different restriction and homology patterns were observed among these isolates, indicating genotypic heterogeneity within this genus and species. It was concluded from this study that restriction endonuclease analysis of B. burgdorferi whole-cell DNA may be a reliable and accurate method for identifying strains or genotypes of the Lyme disease agent.     

Physical mapping of the Borrelia miyamotoi HT31 chromosome in comparison with that of Borrelia turicatae, an etiological agent of tick-borne relapsing fever.

We report the construction of physical maps of chromosomes for Borrelia miyamotoi HT31 (a new species of Borrelia) and Borrelia turicatae (relapsing fever agent) by pulsed-field gel electrophoresis of DNA fragments generated by digestion of chromosomal DNA with rare-cutting restriction endonucleases and reciprocal hybridization. The size of the B. miyamotoi HT31 chromosome was calculated to be approximately 925 kilobase pairs, and the chromosome for B. turicatae was estimated to be 951 kilobase pairs. The chromosomes of B. miyamotoi HT31 and B. turicatae consisted of single linear molecules. The locations of several genes have been assigned to the chromosome maps by Southern hybridization by using specific gene probes. Comparison of the genetic maps of the two species of Borrelia provided evidence that the gene order on the chromosomes is quite similar to that of Borrelia burgdorferi sensu lato strains and is highly conserved in the genus Borrelia.     

Genotypic and phenotypic analysis of Borrelia burgdorferi isolates from The Netherlands.

Sixty-three Borrelia burgdorferi isolates recovered from Ixodes ricinus ticks collected in 17 locations in The Netherlands and three Dutch human skin isolates were characterized by rRNA gene restriction fragment length polymorphism, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and Western blotting (immunoblotting). All three human isolates belonged to B. burgdorferi group VS461. Of the tick isolates, 29 (46%) were B. burgdorferi sensu stricto, 2 (3%) were group VS461, 19 (30%) were Borrelia garinii, and 13 (21%) were different from any previously described genomic species. On the basis of the criteria described, 12 isolates formed a distinct genomic group, designated M19. rRNA gene restriction patterns of the group M19 isolates resembled but were not identical to the B. garinii patterns. Hybridization of digested DNA with a flagellin probe confirmed the separation of group M19 from the B. garinii isolates. One isolate, M63, was different from all the others. In conclusion, the occurrence of B. burgdorferi sensu stricto, B. garinii, and B. burgdorferi group VS461 in ticks from The Netherlands corresponds with the occurrence of these genomic species among tick isolates from other European countries. However, our findings suggest that B. burgdorferi sensu lato probably contains more than three genomic species.     

Detection of Borrelia afzelii, Borrelia burgdorferi sensu stricto, Borrelia garinii and group VS116 by PCR in skin biopsies of patients with erythema migrans and acrodermatitis chronica atrophicans

Objective: To evaluate the diagnostic performance of two polymerase chain reaction (PCR) procedures using skin biopsies of 20 erythema migrans (EM) and 24 acrodermatitis chronica atrophicans (ACA) patients.
Method: One assay amplified a fragment of the outer surface protein (Osp) A gene. The second method amplified the spacer region between the 5S and 23S rRNA genes; hybridization of this fragment allowed identification of Borrelia burgdorferi sensu lato species.
Results: Among EM patients, both assays detected Borrelia DNA in 15 samples. Among ACA patients, the ospA PCR detected 15 positives and 10 samples were positive by 5S–23S PCR. In 19 samples one species was detected, 15 skin biopsies contained Borrelia afzelii , and Borrelia garinii was found in two patients. Group VS116 was detected in two EM patients, and therefore this group has pathogenic potential. Mixed infections of B. afzelii and B. garinii , group VS116 or B. burgdorferi sensu stricto were found in three EM and three ACA patients.
Conclusions: Diagnosis of EM and ACA by PCR is useful and knowledge of the presence of species may be used to predict the course of disease or the need for further antibiotics.     

Phenotypic and Genetic Characterization of a Novel Borrelia burgdorferi Sensu Lato Isolate from a Patient with Lyme Borreliosis

Borrelia burgdorferi sensu lato A14S was cultured from a skin biopsy specimen of a patient with erythema migrans in The Netherlands. This isolate had a unique DNA fingerprint pattern compared to 135 other B. burgdorferi sensu lato isolates. In this study, the isolate A14S was further characterized by protein analysis with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and reactivity with various monoclonal antibodies. In addition, the 16S rRNA, ospA, and ospC genes, as well as the 5S-23S rRNA intergenic spacer DNA, were amplified by PCR, cloned, and sequenced. SDS-PAGE protein profiles and phylogenetic analysis based on all of the analyzed genes confirmed that B. burgdorferi sensu lato A14S was phenotypically and genetically different from the three human pathogenic species B. burgdorferi sensu stricto, Borrelia garinii, and Borrelia afzelii, as well as from other B. burgdorferi sensu lato species. Our findings indicate that Borrelia genomic groups or isolates other than the three well-known human pathogenic species may also cause human Lyme borreliosis.     

Detection and Identification of Ehrlichia, Borrelia burgdorferi Sensu Lato, and Bartonella Species in Dutch Ixodes ricinus Ticks

A sensitive and specific PCR hybridization assay was developed for the simultaneous detection and identification of Ehrlichia and Borrelia burgdorferi sensu lato. In separate assays the 16S rRNA gene of Ehrlichia species and the 23S-5S rRNA spacer region of B. burgdorferi sensu lato were amplified and labeled by PCR. These PCR products were used in a reverse line blot hybridization assay in which oligonucleotide probes are covalently linked to a membrane in parallel lines. Hybridization of the samples with the oligonucleotide probes on this membrane enabled the simultaneous detection and identification of Ehrlichia, B. burgdorferi, and Bartonella species in 40 different samples. The application of the assay to DNA extracts from 121 Ixodes ricinus ticks collected from roe deer demonstrated that 45% of these ticks carried Ehrlichia DNA. More than half of these positive ticks carried species with 16S rRNA gene sequences closely related to those of E. phagocytophila and the human granulocytic ehrlichiosis agent. The majority of the other positive ticks were infected with a newly identified Ehrlichia-like species. In addition, 13% of the ticks were infected with one or more B. burgdorferi genospecies. In more than 70% of the ticks 16S rRNA gene sequences for Bartonella species or other species closely related to Bartonella were found. In five of the ticks both Ehrlichia and B. burgdorferi species were detected.     

Detection and identification of pathogens and host DNA in unfed host-seeking Ixodes ricinus L. (Acari: Ixodidae)

In this study, we have developed molecular methods for the identification of reservoir hosts of sylvatic tick-borne zoonoses. The methods are based on the analysis of the blood meal remnant in the tick gut and include detection of pathogens and identification of the host origin of the blood meal. For host identification, a universal primer pair was used to amplify part of the vertebrate 18S rRNA gene followed by reverse line blot hybridization using subgroup-specific probes. Analyses of DNA from whole blood of vertebrates identified the correct subgroup of a broad range of vertebrate species (e.g., Ruminantia, Leporidea, Canidae, Murinae, Arvicolinae, Insectivora, Galliformes, Passeriformes) using probes based on the 18S rDNA sequences. Host DNA in the remnants of larval blood meals was detected in the gut of Ixodes ricinus nymphs maintained under natural conditions up to 9 mo after molting. For pathogen identification, a multiplex polymerase chain reaction was used that targeted parts of the 18S rRNA gene of piroplasm protozoa, the 16S rRNA gene of bacteria, and the intergenic spacer of the Borrelia burgdorferi genospecies complex. The utility of both methods was demonstrated under laboratory conditions by detecting Babesia microti (Franca) and gerbil DNA in 3-mo-old I. ricinus nymphs that had fed on B. microti-infected gerbils as larvae, and under field conditions by analyzing unfed ticks that were collected in a forest. The field study showed that the majority of ticks had fed on ruminants or birds and few on rodents, which is in accord with our knowledge of the fauna in this forest. Few pathogens were detected but the discovery of Borrelia valaisiana and B. burgdorferi s.s. in ticks that had fed on deer and Borrelia afzelii in a tick that had fed on a bird raises questions about the mode of transmission of these spirochetes and possibly about their host specificity.     

Molecular Typing of Borrelia burgdorferi Sensu Lato: Taxonomic, Epidemiological, and Clinical Implications

Borrelia burgdorferi sensu lato, the spirochete that causes human Lyme borreliosis (LB), is a genetically and phenotypically divergent species. In the past several years, various molecular approaches have been developed and used to determine the phenotypic and genetic heterogeneity within the LB-related spirochetes and their potential association with distinct clinical syndromes. These methods include serotyping, multilocus enzyme electrophoresis, DNA-DNA reassociation analysis, rRNA gene restriction analysis (ribotyping), pulsed-field gel electrophoresis, plasmid fingerprinting, randomly amplified polymorphic DNA fingerprinting analysis, species-specific PCR and PCR-based restriction fragment length polymorphism (RFLP) analysis, and sequence analysis of 16S rRNA and other conserved genes. On the basis of DNA-DNA reassociation analysis, 10 different Borrelia species have been described within the B. burgdorferi sensu lato complex: B. burgdorferi sensu stricto, Borrelia garinii, Borrelia afzelii, Borrelia japonica, Borrelia andersonii, Borrelia valaisiana, Borrelia lusitaniae, Borrelia tanukii, Borrelia turdi, and Borrelia bissettii sp. nov. To date, only B. burgdorferi sensu stricto, B. garinii, and B. afzelii are well known to be responsible for causing human disease. Different Borrelia species have been associated with distinct clinical manifestations of LB. In addition, Borrelia species are differentially distributed worldwide and may be maintained through different transmission cycles in nature. In this paper, the molecular methods used for typing of B. burgdorferi sensu lato are reviewed. The current taxonomic status of B. burgdorferi sensu lato and its epidemiological and clinical implications, especiallly correlation between the variable clinical presentations and the infecting Borrelia species, are discussed in detail.     

Characterization of Lyme borreliosis isolates from patients with erythema migrans and neuroborreliosis in southern Sweden

Southern Sweden is an area of Lyme borreliosis (LB) endemicity, with an incidence of 69 cases per 100,000 inhabitants. The most frequent clinical manifestations are erythema migrans (77%) and neuroborreliosis (16%). There was no record of human Borrelia strains being isolated from patients in this region before the prospective study reported here. Borrelia spirochetes were isolated from skin and cerebrospinal fluid (CSF) from LB patients living in the region. A total of 39 strains were characterized by OspA serotype analysis, species-specific PCR, and signature nucleotide analysis of the 16S rRNA gene. Of 33 skin isolates, 31 (93.9%) were Borrelia afzelii strains and 2 (6.1%) were Borrelia garinii strains. Of six CSF isolates, five (83.3%) were B. garinii and one (16.7%) was B. afzelii. Neither Borrelia burgdorferi sensu stricto strains nor multiple infections were observed. The B. afzelii isolates were of OspA serotype 2. Three B. garinii strains were of OspA serotype 5, and the remaining four strains were of OspA serotype 6. All of the B. garinii strains belonged to the same 16S ribosomal DNA ribotype class. Our findings agree with earlier findings from other geographic regions in Europe where B. afzelii and B. garinii have been recovered predominantly from skin and CSF cultures, respectively. To further study the possible presence in Sweden of the genotype B. burgdorferi sensu stricto, which is known to be present in Europe and to occur predominantly in patients with Lyme arthritis, molecular detection of Borrelia-specific DNA in synovial samples from Lyme arthritis patients should be performed.     

Analysis and comparison of plasmid profiles of Borrelia burgdorferi sensu lato strains.

The relationship between plasmid profiles and genospecies of the Lyme disease borreliae was investigated by using 40 strains from diverse biological and geographical sources. The genospecies of the strains were determined by examination of rRNA gene restriction patterns with cDNA probes complementary to the 16S and 23S rRNAs of Escherichia coli. Plasmid profiles were obtained by pulsed-field gel electrophoresis. The number of plasmids per strain and the size of these plasmids ranged from 4 to 10 and from 13.3 to 57.7 kb, respectively. The strains all contained a single large plasmid of 50 to 57.7 kb, with the exception of two Borrelia garinii strains that contained two or three of the large plasmids. The large plasmids of Borrelia burgdorferi sensu stricto strains ranged in size from 51.4 to 52.7 kb and were consistently smaller than the 54.0- to 57.7-kb plasmids present in B. garinii and Borrelia afzelii. The exceptions of this observation were the two B. garinii strains with multiple large plasmids; in this case the large plasmids were 50.6 to 53 kb. Although a large degree of heterogeneity in the sizes and frequencies of occurrence of smaller plasmids was observed, there were some differences among the three genospecies. The differences in plasmids were further studied by using two BamHI DNA fragments from a 28.7-kb plasmid of B. burgdorferi sensu stricto 297 as probes. Both probes hybridized with the 27- to 29-kb plasmids of B. burgdorferi sensu stricto strains. In contrast, two patterns of hybridization were observed with B. garinii and B. afzelii.(ABSTRACT TRUNCATED AT 250 WORDS)     

中国4株伯氏疏螺旋体基因型鉴定

目的：对广西和贵州4株伯氏疏螺旋体分离株基因进行鉴定。方法：应用聚合酶链反应从3株广西及1株贵州伯氏疏螺旋体分离株的全基因DNA中将5s-23s rRNA间隔区基调出，并克隆至质粒pGEM-T Easy中，构建重组质粒，测序后与国外其分离株进行同源性比较，结果。4株伯氏疏螺旋体均扩增出约242bp的5s-23s rRNA间隔区基因，同源性99％以上，与B.valaisiana基因型的同源性均比其它基因型高，结论：4株莱姆病螺旋体均属于B.valaisiana基因型。     

Genetic and antigenic characterization of Borrelia coriaceae, putative agent of epizootic bovine abortion.

Borrelia coriaceae was characterized genetically and antigenically by utilizing the following techniques: restriction endonuclease analysis, Southern blotting and genomic hybridization, pulsed-field electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and immunoblotting. The B. coriaceae genome revealed unique and characteristic banding patterns both by agarose gel electrophoresis and by hybridization when compared with several Borrelia burgdorferi isolates. Pulsed-field gel electrophoresis demonstrated several linear plasmids ranging from 65 to 30 kilobase pairs. Cross-reaction with B. burgdorferi antigens ranging from 21 to 26 kilodaltons were demonstrated by immunoblotting with rabbit anti-B. coriaceae antiserum. However, most B. coriaceae antigens were quite distinct when compared with B. burgdorferi and Leptospira interrogans antigens.     

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 purified B. burgdorferi DNA, the detection limit of the assay was approximately 0.002 pg of DNA, corresponding to one copy of the B. burgdorferi genome. By using in vitro-cultivated B. burgdorferi without prior DNA purification as the template DNA, 2 to 20 organisms could be detected. A 791-bp DNA fragment was amplified from all of 18 different B. burgdorferi strains tested, as well as from Borrelia hermsii and Borrelia anserina but not from Treponema pallidum. The efficacy of the PCR assay was evaluated on spleen, renal, and urinary bladder tissue specimens from eight experimentally infected gerbils. Specimens from the same organs were cultured in BSK medium in parallel. Of 24 organs, 21 (88%) were PCR positive and 17 (71%) were culture positive. All culture-positive specimens were also PCR positive. Compared with B. burgdorferi cultivation, PCR had at least a comparable diagnostic sensitivity, it was less laborious, and results were available within 1 to 2 days.     

Detection of Borrelia burgdorferi using the polymerase chain reaction.

Segments of the ospA gene of Borrelia burgdorferi were amplified by the polymerase chain reaction (PCR). Oligonucleotide primers used in the reaction flank a 309-base-pair segment within the ospA gene. After 35 cycles of amplification, the product could be detected by agarose gel electrophoresis or dot hybridization with a 32P-labeled probe. This segment was amplified in all strains of B. burgdorferi tested, but it was not detected in other bacterial species. An additional primer pair which has a broad specificity for conserved 16S rRNA sequences that are present in eubacteria amplified a 215-base-pair fragment in all organisms tested. The sensitivity of PCR for the detection of B. burgdorferi in clinical samples was evaluated by seeding blood and urine specimens with B. burgdorferi and subjecting them to amplification. We were able to detect 10 organisms per ml of blood or urine, using PCR with dot hybridization detection. DNA extraction is not required for sample preparation. Blood and urine specimens were obtained from canines with clinical and serologic evidence of Lyme disease and subjected to PCR analysis. Of 17 clinical specimens from 15 animals, one blood specimen showed reactivity in the PCR.     

Restriction fragment length polymorphisms in the ribosomal genes for species identification and subtyping of aerotolerant Campylobacter species.

Whole-cell chromosomal digests of 84 strains of aerotolerant Campylobacter (AC) were examined by using PvuII restriction fragment length polymorphisms of rRNA genes followed by hybridization with Escherichia coli 16S and 23S rRNA (ribotyping). The AC strains belonged to Campylobacter cryaerophila (n = 13) and a newly defined species, "C. butzleri" (n = 64). Strains of C. cryaerophila belonged to two hybridization groups: DNA group 1A (including the type strain of C. cryaerophila) and DNA group 1B (J. A. Kiehlbauch, D. J. Brenner, M. A. Nicholson, C. N. Baker, C. M. Patton, A. G. Steigerwalt, and I. K. Wachsmuth, J. Clin. Microbiol. 29:376-385, 1991). Six AC strains not classified as C. cryaerophila or "C. butzleri" were also included. All 35 sporadic human and animal isolates of "C. butzleri" sent to the Centers for Disease Control for identification showed different ribotype patterns. However, most "C. butzleri" strains contained common bands at approximately 3.0, 6.2, 12.0, and 15.0 kb; the 3.0-kb band was present in all but four strains. An additional 23 strains of "C. butzleri," isolated as part of special studies, contained the 3.0-kb band. Thus, on the basis of visual identification of the 3.0-kb band, 94% of available strains were correctly identified as "C. butzleri." Ribotyping demonstrated that C. cryaerophila strains (DNA groups 1A and 1B) were different from C. butzleri strains. All C. cryaerophila strains demonstrated a common ribosomal DNA restriction fragment of 3.2 kb; DNA group 1B strains contained an additional common band at 2.6 kb. Ribotyping patterns of AC species were easily distinguished from patterns of other Campylobacter, Helicobacter, and Wolinella species.(ABSTRACT TRUNCATED AT 250 WORDS)     

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 FCB was clearly separated with the group identified as B. turicatae, confirming this bacterium as a relapsing fever spirochete. Therefore, the potential for tick-borne relapsing fever in humans and other animals exists in Florida and future efforts are needed to determine the enzootic hosts and distribution of this spirochete in the southeastern United States. Analysis of plasmids demonstrated both linear and circular forms in B. turicatae but only linear plasmids in B. parkeri, which should be of interest to investigators concerned with plasmid diversity and evolution within this group of spirochetes.