PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “TREPONEMA PALLIDUM”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

Antigenic relatedness and N-terminal sequence homology define two classes of periplasmic flagellar proteins of Treponema pallidum subsp. pallidum and Treponema phagedenis.

The periplasmic flagella of many spirochetes contain multiple proteins. In this study, two-dimensional electrophoresis, Western blotting (immunoblotting), immunoperoxidase staining, and N-terminal amino acid sequence analysis were used to characterize the individual periplasmic flagellar proteins of Treponema pallidum subsp. pallidum (Nichols strain) and T. phagedenis Kazan 5. Purified T. pallidum periplasmic flagella contained six proteins (Mrs = 37,000, 34,500, 33,000, 30,000, 29,000, and 27,000), whereas T. phagedenis periplasmic flagella contained a major 39,000-Mr protein and a group of two major and two minor 33,000- to 34,000-Mr polypeptide species; 37,000- and 30,000-Mr proteins were also present in some T. phagedenis preparations. Immunoblotting with monospecific antisera and monoclonal antibodies and N-terminal sequence analysis indicated that the major periplasmic flagellar proteins were divided into two distinct classes, designated class A and class B. Class A proteins consisted of the 37-kilodalton (kDa) protein of T. pallidum and the 39-kDa polypeptide of T. phagedenis; class B included the T. pallidum 34.5-, 33-, and 30-kDa proteins and the four 33- and 34-kDa polypeptide species of T. phagedenis. The proteins within each class were immunologically cross-reactive and possessed similar N-terminal sequences (67 to 95% homology); no cross-reactivity or sequence homology was evident between the two classes. Anti-class A or anti-class B antibodies did not react with the 29- or 27-kDa polypeptides of T. pallidum or the 37- and 30-kDa T. phagedenis proteins, indicating that these proteins are antigenically unrelated to the class A and class B proteins. The lack of complete N-terminal sequence homology among the major periplasmic flagellar proteins of each organism indicates that they are most likely encoded by separate structural genes. Furthermore, the N-terminal sequences of T. phagedenis and T. pallidum periplasmic flagellar proteins are highly conserved, despite the genetic dissimilarity of these two species.

Amino Acid Sequence↗

Activation of the classical and alternative pathways of complement by Treponema pallidum subsp. pallidum and Treponema vincentii.

Both in vivo and in vitro studies have indicated that complement plays an important role in the syphilitic immune responses. Few quantitative data are available concerning activation of the classical pathway by Treponema pallidum subsp. pallidum, and no information is available on treponemal activation of the alternative pathway. Activation of both pathways was compared by using T. pallidum subsp. pallidum and the nonpathogen T. vincentii. With rabbit and human sources of complement, both organisms rapidly activated the classical pathway, as shown by hemolysis of sensitized sheep erythrocytes and by the generation of soluble C4a. With human sources of complement, both organisms also activated the alternative pathway, as shown by hemolysis of rabbit erythrocytes and by the generation of soluble C3a in the presence of magnesium ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA). During incubation, organisms remained actively mobile and did not lyse, indicating that activation was a function of complement reactivity with the intact outer treponemal surface. In addition, freshly harvested T. pallidum subsp. pallidum immediately activated both pathways of complement; preincubation of organisms did not enhance complement reactivity. T. vincentii was a more potent activator of this pathway. T. pallidum subsp. pallidum contained almost four times as much surface sialic acid as T. vincentii did. When sialic acid was enzymatically removed from T. pallidum subsp. pallidum, enhanced activation of the alternative pathway was detected. It is proposed that T. pallidum subsp. pallidum retards complement-mediated damage by the alternative pathway through surface-associated sialic acid. This may be an important virulence determinant that enables these organisms to readily disseminate through the bloodstream to infect other tissues.

Animals↗

Multiple alleles of Treponema pallidum repeat gene D in Treponema pallidum isolates.

Two new tprD alleles have been identified in Treponema pallidum: tprD2 is found in 7 of 12 T. pallidum subsp. pallidum isolates and 7 of 8 non-pallidum isolates, and tprD3 is found in one T. pallidum subsp. pertenue isolate. Antibodies against TprD2 are found in persons with syphilis, demonstrating that tprD2 is expressed during infection.

Alleles↗

Ultrastructural studies of treponemes: location of axial filaments and some dimensions of Treponema pallidum (Nichols strain), Treponema denticola, and Treponema reiteri.

Ultrathin sections of Treponema pallidum (Nichols strain), T. denticola (microdentium), and T. reiteri have been studied in the electron microscope to determine the location of the axial filaments and some of the dimensions of these organisms. The axial filaments of T. pallidum (Nichols strain) have been seen to be tubular in cross section with an overall diameter of 21.0 +/- 0.73 nm, and an electron-lucent core of 8.0 nm. The filaments were found to lie on the outside of the organism which had only one membranous structure surrounding the protoplasmic core. These findings were in contrast to those obtained for T. denticola and T. reiteri where the axial filaments did not exhibit a hollow core and were located between an outer membrane and an inner membrane surrounding the protoplasmic core. The outside diameter of T. denticola was determined to be 224.9 +/- 2.83 nm, and that of T. reiteri as 331.0 +/- 4.15 nm, contrasting with T. pallidum (Nichols strain) which had a diameter of 163.0 +/- 1.9 nm.

Animals↗

[Evaluation of gelatin particle agglutination method for detection of Treponema pallidum antibody].

Treponema pallidum hemagglutination (HA) is one of the most frequently used methods for the detection of Treponema pallidum (T. pallidum) antibodies. Recently, an innovative agglutination method using artificial carriers was newly developed, and is now available as a routine method. In order to compare the newly developed particle agglutination (PA) method (FUJIREBIO INC.) with the conventional HA method, T. pallidum antibody titers of numerous sera were measured by respective methods. In the stability study, reconstituted reagent was stable for at least three weeks. Sample inactivation (56 degrees C/30 min) demonstrated no effect on the test results. Among 800 sera, 132 (16.6%) positives (+), 633 (79.1%) negatives (-) and (4.3%) indeterminates (+) were obtained by HA method. Meanwhile, 144 (18.0%) positives (+), 627 (78.4%) negatives (-) and 29 (3.6%) indeterminates (+) were obtained by PA method. The correlation between PA and HA method was 97.8%, and the antibody titers obtained by PA method showed good correlation with HA method. Those samples which showed discrepancy between PA and HA method in the above study were further examined with fluorescent treponemal antibody-absorption (FTA-ABS) method. The results obtained from FTA-ABS method were almost consistent with those obtained from PA method. For respective syphilis patients in stage I and II, antibody titer was monitored by HA, PA and RPR method. The results indicated that changes in antibody titer obtained from PA method was approximately the same as the titer changes obtained from RPR method. Namely, PA method detected the presence of IgM earlier than HA method.(ABSTRACT TRUNCATED AT 250 WORDS)

Agglutination Tests↗

Polypeptides of Treponema pallidum: progress toward understanding their structural, functional, and immunologic roles. Treponema Pallidum Polypeptide Research Group.

Treponema pallidum subsp. pallidum, the spirochete that causes syphilis, is unusual in a number of respects, including its small genome size, inability to grow under standard in vitro culture conditions, microaerophilism, apparent paucity of outer membrane proteins, structurally complex periplasmic flagella, and ability to evade the host immune responses and cause disease over a period of years to decades. Many of these attributes are related ultimately to its protein content. Our knowledge of the activities, structure, and immunogenicity of its proteins has been expanded by the application of recombinant DNA, hybridoma, and structural fractionation techniques. The purpose of this monograph is to summarize and correlate this new information by using two-dimensional gel electrophoresis, monoclonal antibody reactivity, sequence data, and other properties as the bases of polypeptide identification. The protein profiles of the T. pallidum subspecies causing syphilis, yaws, and endemic syphilis are virtually indistinguishable but differ considerably from those of other treponemal species. Among the most abundant polypeptides are a group of lipoproteins of unknown function that appear to be important in the immune response during syphilitic infection. The periplasmic flagella of T. pallidum and other spirochetes are unique with regard to their protein content and ultrastructure, as well as their periplasmic location. They are composed of three core proteins (homologous to the other members of the eubacterial flagellin family) and a single, unrelated sheath protein; the functional significance of this arrangement is not understood at present. Although the bacterium contains the chaperonins GroEL and DnaK, these proteins are not under the control of the heat shock regulon as they are in most organisms. Studies of the immunogenicity of T. pallidum proteins indicate that many may be useful for immunodiagnosis and immunoprotection. Future goals in T. pallidum polypeptide research include continued elucidation of their structural locations and functional activities, identification and characterization of the low-abundance outer membrane proteins, further study of the immunoprotective and immunodiagnostic potential of T. pallidum proteins, and clarification of the roles of treponemal proteins in pathogenesis.

Amino Acid Sequence↗