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PubMed2000

Whole genome analyses of transporters in spirochetes: Borrelia burgdorferi and Treponema pallidum.

The completely sequenced genomes of two spirochetes, Borrelia burgdorferi(Bbu) and Treponema pallidum (Tpa) were analyzed for the distribution of transporter types. Both organisms exhibited fewer proteins with >7 alpha-helical transmembrane spanners (TMSs), and fewer identified transport systems per megabase pair of DNA than most other prokaryotes analyzed. Each organism exhibits one recognizable ion channel protein of the MscS family. Tpa has twice as many primary carriers as Bbu but lacks PTS permeases that are plentiful in Bbu. Tpa is the only prokaryote so far sequenced which has two F-type ATPases. Large families of secondary nutrient uptake carriers (MFS and APC) that are prevalent in other organisms are essentially lacking in Spirochetes. The largest Spirochete secondary carrier families consist of efflux systems. While both Bbu and Tpa exhibit an unusual degree of transporter diversity, major differences in specificity exist between these two organisms.

Borrelia burgdorferi Group↗
PubMed2000

Insertional inactivation of the prtP gene of Treponema denticola confirms dentilisin's disruption of epithelial junctions.

The purified chymotrypsin-like protease of Treponema denticola, designated dentilisin or PrtP (DDBJ accession no. D83264), can disrupt cell-cell junctions and impair the barrier function of epithelial monolayers in vitro. Serine protease inhibitors block these effects. Yet, the protease is apparently less significant in perturbing intracellular signaling pathways and cytoskeletal rearrangement in fibroblasts. The purpose of this study was to use a PrtP-deficient mutant of T. denticola to confirm that the cytopathic effects of whole bacteria and its outer membrane on epithelial cell junctions were primarily accounted for by the activity of this protease. The prtP gene of ATCC 35405 was inactivated by insertion of an erythromycin-resistance cassette, yielding mutant K1. In contrast to wildtype ATCC 35405, mutant K1 grew in tight cell aggregates; the cells had a disrupted outer sheath, as determined by electron microscopy. When compared by silver stained SDS-PAGE of sonicated extracts of whole cells, the extract of mutant K1 was missing a band at approximately 90 kDa that was present in the wildtype ATCC 35405 strain. Whole cells and Triton X-100 outer membrane (OM) extracts of K1 and the wildtype strains were compared 1) for SAAPNA degrading activity by a colorimetric assay, 2) for stress fiber disruption in human gingival fibroblasts (HGF) by fluorescence microscopy of TRITC-phalloidin stained cells, and 3) the OM extracts only for perturbation of HEp-2 epithelial monolayers by electrical cell-substrate impedance sensing (ECIS). Mutant K-1 cells and OM had no SAPPNA degrading activity that is characteristic of dentilisin. K1 cells had HGF stress fiber disrupting activity (86 +/- 4.5% of HGFs affected) equivalent to both 35405 wildtype strains (84 +/- 3.9% and 71 +/- 14.1% of HGF, respectively). Yet, mutant K1 OM had diminished stress fiber disrupting activity (12.9 +/- 4.6% of HGF) compared with its parent 35405's OM (94.6 +/- 2.9%). The major cytopathogenic difference between the K1 mutant and wildtype strains was in their OM's effect on epithelial cell junctions. ATCC 35405 OM completely disrupted epithelial resistance in a concentration - dependent manner; mutant K1 OM had negligible effects. These data confirm that inactivation of the prtP gene completely reverses T. denticola's disruption of epithelial junctions, but there are pleiotropic effects of the mutation that may account for its apparently diminished effects on the cytoskeleton of HGF when the cells were challenged with OM extracts.

Bacterial Adhesion↗
PubMed1975

Swine dysentery: pathogenicity of Treponema hyodysenteriae.

When pure cultures of Treponema hyodysenteriae were orally inoculated into pigs, severe disease characteristic of swine dysentery developed. Less severe lesions were produced by oral inoculation of infective minced colon. Noninoculated pigs were used as controls. Inoculations of surgically isolated porcine colonic loops with either pure cultures or infective minced colon produced lesions only in the injected loop; the adjacent noninjected colon remained normal. Pigs and other experimental animals, including rabbits, guinea pigs, and mice, inoculated with washed cultures by various parenteral routes remained normal.

Administration, Oral↗
PubMed2002

[Laboratory-based evaluation of a newly developed immunochromatographic test method by using synthesized oligonucleotide-bound protein probes for simultaneous detection of hepatitis B surface antigen (HBsAg) and specific antibodies to Treponema pallidum].

An immunochromatographic test method using synthesized oligonucleotide-bound protein probes was newly developed and evaluated for simultaneous detection of hepatitis B surface antigen (HBsAg) and specific antibodies to Treponema pallidum (TP). The test principle includes, first, antigen-antibody reaction, and secondly, DNA (oligonucleotide)-DNA interaction. The test device is composed of colloidal gold-labeled HBs antibody and TP antigen, and oligonucleotide-labeled HBs antibody and TP antigen. When the test sample contains HBsAg and/or TP specific antibody, the colloidal gold-labeled probes and oligonucleotide-labeled probes will make a sandwich complex with the target. Then, the formed complex migrates and is immobilized by the respective complementary oligonucleotide fixed on the different lines of the membrane. The color development of colloidal gold was visually read after 20 min and/or 60 min incubation, and easily interpretable, positive or negative. When the performance panels of Boston Biomedica Inc. (BBI) for HBsAg and TP-specific antibody, the results indicated; first, the most positive serum and plasma specimens with 1.2 IU/ml of HBsAg were correctly determined as positive, and secondly, all the test results for TP-specific antibody were comparable to the results of fluorescent treponemal antibody test (FTA-ABS). However, when the seroconversion panel of BBI for hepatitis B virus (HBV) infection, the seroconversion was delayed 20 to 30 days when compared to HBV DNA detection. Also, when the clinical serum and plasma samples were tested, sensitivity and specificity were estimated to be 87.0% and 100% for HBsAg, and both 100% for TP-specific antibody, respectively. With these results, we can conclude that this newly developed immunochromato-graphic test method will be applicable to simultaneous detection of multiple antigen and/or specific antibody in a single device, and will be expected to be widely applied in a clinical setting.

Antibodies, Bacterial↗
PubMed1992

Treponema pallidum membrane protein A ELISA: a new test for screening and diagnosis of syphilis.

A new ELISA test system for screening antibodies directed against Treponema pallidum is presented. The ELISA is based on a recombinant DNA-derived T. pallidum membrane protein A (TmpA). It makes the production of the kit easier as it abandons the necessity to culture T. pallidum in living animals. The specificity and sensitivity of the ELISA are comparable with those of the TPHA and FTA-ABS. The test gives only a positive result when there are antibodies against the TmpA antigen and, therefore, it gives in screening (e.g. blood donors) no false-positive reaction in persons who, due to an old well-treated infection, have a so-called serological scar. As these donors are noninfective, they should be concerned as negative in syphilis screening.

Antigens, Surface↗
PubMed1992

Purification and substrate specificity of an endopeptidase from the human oral spirochete Treponema denticola ATCC 35405, active on furylacryloyl-Leu-Gly-Pro-Ala and bradykinin.

An endopeptidase was purified to homogeneity from the cell extracts of Treponema denticola ATCC 35405 (a human oral spirochete) by a procedure that comprised dialysis, anion exchange fast protein liquid chromatography (FPLC), hydroxylapatite FPLC, immobilized metal affinity FPLC, FPLC chromatofocusing, and two consecutive gel permeation FPLC steps. The enzyme is a 62-kDa protein with an isoelectric point of 6.5-7.0. Experiments with enzyme inhibitors suggest that this enzyme is a metallopeptidase and that its activity is not dependent on sulfhydryl or serine residues. The enzyme is active on furylacryloyl-Leu-Gly-Pro-Ala (FALGPA; pH optimum near 6.25), bradykinin (Bk), and several Bk-related peptides. In FALGPA, the cleavage site is the Leu-Gly bond. An imino acid is absolutely necessary in position P'2. The shortest hydrolyzed peptide was FALGPA, the hydrolysis of which is strongly and competitively inhibited by Bk (Ki = 5.0 microM). The pyrophosphate ion and phosphoramidon also inhibited the hydrolysis of FALGPA. The enzyme does not hydrolyze all typical synthetic collagenase substrates, Azocoll, Azocasein, or Type I and Type IV collagens, or any other proteins tested. In Bk-related peptides, the hydrolyzed bond was Phe5-Ser6. Since a Bk antagonist and a Bk-potentiating pentapeptide also were good substrates, it is possible that the enzyme hydrolyzes Bks and related peptides only because of the coincidental, specific amino acid sequence of those substrates. A proposal is made that since a substantial portion of the amino acid sequence of FALGPA is present in collagen (and additionally acknowledging that the furylacryloyl residue structurally resembles that of proline), the natural substrates of this enzyme may be small, soluble collagen fragments produced by other enzymes from periodontal connective tissue, and that such peptides are important for the nutrition and pathogenicity of T. denticola.

Acrylates↗
PubMed1956

Treponema pallidum agglutination tests.

One approach to obviating some of the difficulties and complexities of the Treponema pallidum immobilization (TPI) test is to be found in the use of T. pallidum as an antigen in agglutination tests. The four main representative techniques of such tests are compared with respect to: strain of organism used, treatment of rabbits, time of harvesting, extracting medium, method of inactivation, preservative, and reagent. The results obtained with the different techniques are then reviewed and the various difficulties met in each are discussed.The authors consider that the T. pallidum agglutination tests do not yet have a diagnostic value equal to that of the TPI test; the technical difficulties have not yet been overcome, and the immunological interpretation of results is by no means clear. Much still has to be done, and indeed it is possible that entirely different methods may even supersede techniques using whole, virulent T. pallidum as antigen.

Agglutination Tests↗
PubMed1992

Production of rheumatoid factor in adoptively immune guinea-pigs after challenge with Treponema pallidum.

Guinea-pigs of inbred strains 2 and C4D were infused with various concentrations (1 x 10(8) to 4 x 10(8) of syngeneic nylon wool-purified Treponema pallidum-immune T lymphocytes (TPI-T) and challenged 24 hr later with virulent T. pallidum (10(8) organisms). The degree of protection depended on the number of infused T cells and was associated with an accelerated production of IgM rheumatoid factor (RF). Fully protected animals (4 x 10(8) TPI-T) did not produce treponemal antibodies or circulating immune complexes (CIC) but produced IgM RF detectable 10 days after infection. Partially protected animals (< or = 2 x 10(8) TPI-T) produced, 30 days post-infection, relatively low levels of treponemal antibodies but high levels of CIC and RF. Control animals infused with 2 x 10(8) TPI-T lymphocytes but not infected with T. pallidum, when monitored for a period of 6 weeks, did not produce treponemal antibodies, CIC, or RF, excluding the possibility that IgM RF could be generated by the donor's B cells contaminating (circa 3%) the TPI-T lymphocytes. Moreover, unprotected syngeneic control animals infused, prior to infection, with T. phagedenis biotype Reiter-immune T cells or with T. pallidum-free testicular inflammatory fluid-immune T cells responded with increasing levels of treponemal antibodies; only a few animals produced RF and CIC 5 months after infection similarly to control guinea-pigs infected only. The production of RF in partially protected animals responding to infection with treponemal antibodies and CIC was apparently associated with the presence of the CIC; but the mechanism of RF production in fully protected animals in which no antibodies or CIC were detected is currently unknown.

Animals↗
PubMed1978

Parenteral immunization of pigs against infection with Treponema hyodysenteriae.

Six intravenous injections of formalin-inactivated Treponema hyodysenteriae were given to 8 specific-pathogen-free pigs at 6-day intervals. The 8 vaccinated and 8 control pigs were challenged intragastrically with pure cultures of T hyodysenteriae 7 and 8 days after the last intravenous injection. Clinical signs of swine dysentery were observed in all 8 control pigs, but was observed in only 1 of the immunized pigs. Three control pigs died. These findings suggest that parenteral immunization with T hyodysenteriae provided a marked degree of protection against subsequent intragastric challenge exposure with the homologous isolate of T hyodysenteriae.

Animals↗
PubMed2004

Neisseria gonorrhoea, Chlamydia trachomatis, and Treponema pallidum infection in antenatal and gynecological patients at Korle-Bu Teaching Hospital, Ghana.

Five hundred and seventeen women attending the gynecology and obstetrics clinics of the Korle-Bu Teaching Hospital were examined for sexually transmitted infections (STIs). Vaginal swabs were examined for Trichomonas vaginalis, Candida albicans, and Gardnerella vaginalis infection. Endocervical swabs were examined for Neisseria gonorrhoea and Chlamydia trachomatis using a recently developed RNA detection kit. Strain typing was performed to identify serovars of C. trachomatis. Sera were analyzed for Treponema pallidum with a passive-particle agglutination assay kit. The prevalence of infection with N. gonorrhoea was 0.6%, C. trachomatis 3.0%, and T. pallidum 5.6%. Eight samples were PCR-positive for C. trachomatis. Five of these were serovar G, and the rest were serovar E. All cases of mixed infections occurred in pregnant women. In conclusion, a high transmissible risk of T. pallidum infection was observed among our study population and in particular among our pregnant women. The absence of association between the presenting symptoms, clinical findings, and specific pathogens has implications for the syndromic approach to STI case management. The low prevalence of C. trachomatis and N. gonorrhoea may be due to self medication and requires further research in primary health institutions in rural areas to compare rates.

Adolescent↗
PubMed2004

[Cloning and expression of Treponema pallidum antigen TpN17 and an epitope of TpN44.5 and clinical application].

OBJECTIVE: To investigate the cloning and expression of Treponema pallidum (TP) specific antigen TpN17 and an epitope of TpN44.5 and the clinical application of this fusion antigen. METHODS: TpN17 gene was amplified from the genome of TP and an epitope of TpN44.5 was spliced to the 5' end of TpN17 gene. This modified TpN17 gene was cloned into the expression vector pGEX4T-2. The recombinant fusion antigen was purified by affinity chromatography and then an enzyme-linked immunosorbent assay (ELISA) kit was prepared. With this kit, the sera of 10 normal persons and 10 TP patients were tested. RESULTS: The molecular weight of the purified fusion antigen was 45,000. Tested with ELISA, 10 serum samples of the TP patients were positive and another 10 of the normal persons were negative. ELISA equipped with the GST-epi-TpN17 antigen showed higher sensitivity and specificity as compared with routine methods. CONCLUSION: The recombinant fusion TP specific antigen GST-epi-TpN17 was suitable for the preparation of ELISA kit in clinical examinations.

Antigens, Bacterial↗
PubMed2005

Association between coinfection of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Treponema denticola and periodontal tissue destruction in chronic periodontitis.

BACKGROUND: The association between the infection of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans and Treponema denticola in chronic periodontitis (CP) and the severity of periodontal disease remains to be elucidated. The aim of this study was to investigate the subgingival infection frequencies of three periodontopathic bacteria in Chinese CP patients and to evaluate the correlations between infection by these bacteria and periodontal destruction. METHODS: A multiple PCR assay using primers derived from 16SrDNA genes of P. gingivalis, A. actinomycetemcomitans and T. denticola was established to measure simultaneously the presence of the three microbes in 162 subgingival samples from 81 Chinese CP patients. RESULTS: The positive rates of P. gingivalis, A. actinomycetemcomitans and T. denticola in the subgingival samples were 84.6%, 83.3% and 88.3%, respectively. Of the subgingival samples, 68% revealed the coinfection of all the three microbes. The infection rates with P. gingivalis, A. actinomycetemcomitans or T. denticola alone was 5.9% (1/17), 17.6% (3/17) and 76.5% (13/17), respectively. A close association was present between the A. actinomycetemcomitans infection and gingival index (GI) (P < 0.01), but not between P. gingivalis or T. denticola infection and GI (P > 0.05). P. gingivalis and A. actinomycetemcomitans were more frequently detectable in middle and deep pockets than in shallow ones (P < 0.01), while T. denticola was found remarkably often in deep pockets (P < 0.05). The coinfection rate of the three microbes was significantly higher in sites with severe periodontitis than in those with mild periodontitis (P < 0.01). CONCLUSIONS: The multiple PCR established in this study can be used as a sensitive and specific method to simultaneously detect all three microbes in subgingival samples. A. actinomycetemcomitans infection may be associated with CP and play an important role in the periodontal tissue destruction. The coinfection of P. gingivalis, A. actinomycetemcomitans and T. denticola can cause more serious periodontal destruction than infection of any one or two of the three microbes.

Adult↗
PubMed2005

[Cloning and expression of outer membrane protein gene Gpd from Treponema pallidum and preliminary studies on its immunogenicity in rabbits].

To construct the recombinant plasmid of Eukaryotic expression containing Gpd gene from Treponema Pallidum and study its immunogenicity in New Zealand White rabbits. Gpd gene was amplified from the genomic DNA of T. pallidum and cloned into appropriate site of pcDNA3. 1 ( + ) vector. After verified that the Gpd antigen gene could be expressed in HeLa cells by Western blot and immunocytochemistry, recombinant plasmids pcDNA3.1 ( + )-Gpd, control plasmid pcDNA3. 1 ( + ) or PBS buffer were administered in three groups of New Zeal and White rabbits. Booster immunizations were employed at 2-week interval for three times. ELISA was used for the quantitative detection of the specific antibody in the sera of rabbits. The proliferation response of spleen cells was detected by MTT assay. The results of the Western blot and immunocytochemistry showed that Gpd gene constructed in pcDNA3.1 ( + ) vector could express a fusion protein with a calculated molecular mass of 41kD in HeLa cells and react with positive blood serum from syphilis patients. The significant specific antibody IgG titers were observed and the highest titer was 1:1024 in rabbits after three times with pcDNA3.1 ( + )-Gpd. The proliferation response of spleen cells were significantly higher than that of rabbits injected with pcDNA3.1 ( + ) (p < 0.05). All above results establish a solid basis for future studying the biological activities of Gpd and benefit the development of the Syphilis DNA vaccine.

Animals↗
PubMed2005

[Research and development of a piezoelectric immunosensor for detecting Treponema pallidum].

We utilized polyethylenimine (PEI) and Glu solution to immobilize the antibody of Treponema Pallidum on the silver electrode of piezoelectric quartz crystal and detect the standard antigen solution at different concentration. The antibody keeps the intrinsic Y type molecular structure revealed by AFM. The resonant range of the sensor is between 5 x 10(-5) - 1.25 x 10(-4) g/mL and the correlation coefficient is 0.9976, the optimal resonance pH is 7.5. We found the sensor having good selectivity in comparison with the method using BSA. At last, a discussion on the reproducibility of the sensor is presented.

Antibodies, Bacterial↗
PubMed2006

[Molecular detection and subtyping of Treponema pallidum subsp. pallidum in clinical specimens].

An in-house two-step nested PCR amplification targeting the tmpC gene (TP0319, encoding putative membrane lipoprotein) was used for detection of chromosomal DNA of Treponema pallidum subsp. pallidum in clinical specimens. We tested 138 blood serum samples from 111 adult patients with suspected, primary, secondary, early or late latent syphilis. T. p. pallidum DNA was not detected in any of the analyzed specimens. Out of 11 mucocutaneous swabs (7 genital and 4 pharyngeal), 6 collected from 3 patients with primary or secondary syphilis tested positive. One skin swab from a patient with early congenital syphilis was also positive as were his serum and cerebrospinal fluid samples. DNA sequencing of the genes TP0136 and TP0548 from the positive samples revealed two strains with DNA sequences identical to that of T. p. pallidum strain SS14 and two unique previously undescribed T. p. pallidum strains. The advances in molecular typing of T. p. pallidum in clinical specimens will be of relevance to the epidemiology of syphilis and will allow for clinical discrimination between reinfection and syphilitic reactivation.

Adult↗
PubMed1991

Lipoproteins of Borrelia burgdorferi and Treponema pallidum activate cachectin/tumor necrosis factor synthesis. Analysis using a CAT reporter construct.

Lipoproteins from two pathogenic spirochetes (Borrelia burgdorferi and Treponema pallidum) induced the biosynthesis of TNF in murine macrophages and in permanently transformed macrophages of the cell line RAW 264.7. Induction was studied by measuring the secretion of biologically active TNF and by measuring the activity of the reporter enzyme chloramphenicol acetyltransferase (CAT) produced within macrophages transfected with an endotoxin-responsive CAT construct. Several lines of evidence indicated that the induction of TNF and CAT was attributable to the spirochete lipoproteins rather than to contaminating or endogenous LPS: 1) the dose response curves observed for the lipoproteins were markedly different from those obtained with LPS; 2) lipoprotein-mediated activation was unaffected by amounts of polymyxin B that completely neutralized the induction of TNF and CAT by LPS, 3) low concentrations of the lipoproteins induced TNF in macrophages from endotoxin-unresponsive C3H/HeJ mice as effectively as in macrophages from normal C3H/HeN mice, and 4) isolated spirochete lipoproteins, but not a non-lipoprotein immunogen, were potent inducers of CAT in the transformed macrophages. Moreover, LPS was not detected in the B. burgdorferi lipoprotein mixtures by Limulus amebocyte lysate assay. Proteolytic digestion of the intact bacterial protein preparations only modestly diminished their ability to activate the cells, suggesting that small lipopeptides comprise the biologically active portions of the molecules, as is the case with the murein lipoprotein of Escherichia coli. Through their ability to induce TNF production by macrophages, spirochete lipoproteins may play important roles in the development of the local inflammatory changes and the systemic manifestations that characterize syphilis and Lyme disease.

Animals↗
PubMed1991

Identification of Treponema pallidum in amniotic fluid and fetal blood from pregnancies complicated by congenital syphilis.

Two pregnant women with secondary syphilis underwent amniocentesis and evaluation for fetal syphilis. In both cases, motile spirochetes, typical of Treponema pallidum, were observed during dark-field microscopic examination of the amniotic fluid. The presence of T pallidum was confirmed by antitreponemal monoclonal antibody immunofluorescence assays and by rabbit infectivity tests using the amniotic fluid. In the first case, an infant at 35 weeks' gestation delivered within 24 hours of amniocentesis had hepatosplenomegaly, osteochondritis, and neurosyphilis. In the second case, a fetus at 24 weeks' gestation was hydropic and a fetal blood sample showed anemia, thrombocytopenia, and elevated liver enzymes. Fetal syphilis was confirmed by rabbit infectivity testing using fetal blood obtained by funipuncture. This is the first report of the diagnosis of fetal syphilis by funipuncture and confirmation of the presence of virulent T pallidum in the blood of a human fetus. The mother was treated for secondary syphilis, but the infant had residual signs of congenital infection at birth 14 weeks later. Neonatal serum from the first case and fetal serum from the second case showed specific immunoglobulin M reactivity with the 47-kd antigen of T pallidum by Western blot assays. A new wild-type strain of T pallidum, designated DAL-1, was isolated from the amniotic fluid of the first case and is available for future studies. We conclude that the presence of T pallidum in amniotic fluid or fetal blood indicates fetal-placental infection. Further investigation is necessary to determine the pathogenesis of amniotic fluid infection and its role in the prenatal diagnosis of congenital syphilis.

Adult↗
PubMed1991

Identification of T. pallidum polypeptides: a comparative study between the protein profiles of in vitro cultivated and in vivo propagated Treponema pallidum subsp. pallidum by two-dimensional polyacrylamide gel electrophoresis.

Protein profiles of in vivo propagated and in vitro cultivated Treponema pallidum subsp. pallidum (Nichols strain) were analyzed using two-dimensional gel electrophoresis (2D-PAGE). A comparative study between the two protein profiles (as detected by silver stain, Western blotting, and autoradiography) demonstrated two in vitro synthesized polypeptides with approximate molecular masses of 29- and 35 kDa (both with pI 5.62) which were absent in the protein profile of the in vivo propagated T. pallidum. It also was demonstrated that the in vitro cultivated organisms lacked an antigenic polypeptide (as judged by Western blots) of approximate molecular weight 35 kDa (pI 5.34) which was present in the in vivo propagated organisms. To determine the cellular location of these polypeptides, the outer membrane proteins of T. pallidum was extracted with Triton X-114. The extracted proteins were subjected to phase partitioning and the 2D-PAGE protein profiles of the detergent and aqueous phases were compared. The results indicated that in vitro cultivation caused some changes in the cytoplasmic protein profiles of T. pallidum, but no changes were detected in the profiles of the membrane proteins.

Antigens, Bacterial↗