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Publications (4)13 Total impact

  • Article: Short Communication: Identification and Sequences of the Treponema pallidum flhA, flhF, and orf 304 Genes
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    ABSTRACT: The recently identified flu operon of Treponema pallidum contains several genes that encode motilityrelated proteins. We have determined the nucleotide sequences of three genes, designated flhA, flhF, and or/304, that are located immediately downstream of the flhB gene in the fla operon. The flhA gene encodes a 707-amino acid protein that contains five putative membrane spanning domains. FlhA has strong homology with members of a family of proteins that are involved in flagellar biogenesis and regulation/secretion of virulence-related proteins. The flhF gene encodes a 437-amino acid protein that contains three consensus elements that are characteristic of a GTP-binding domain. The or/304 gene encodes a 304-amino acid protein that contains a consensus ATP-binding motif. The order of the flhA, flhF, and or/304 genes is identical to that of corresponding genes in the Bacillus subtilis che/fla operon. Due to the location of the flhA, flhF and or/304 genes in the T. pallidum fla operon, we hypothesize that the FlhA, FlhF, and Orf304 proteins are involved in the biogenesis/assembly of treponemal periplasmic flagella.
    07/2009; 7(2):107-116.
  • Article: Identification and sequence analysis of Treponema pallidum tprJ, a member of a polymorphic multigene family
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    ABSTRACT: TnphoA mutagenesis was used to identify genes encoding exported proteins in a genomic DNA library of Treponema pallidum, the syphilis agent. The nucleotide sequence of an open reading frame (tprJ) that encodes a 755-amino acid protein with a predicted molecular mass of 81.1 kDa was determined. The deduced amino acid sequence of TprJ has homology to the major surface protein of Treponema denticola, a periodontal pathogen. Southern hybridization and genomic DNA sequence analysis indicate that tprJ is a member of a polymorphic multigene family. RT-PCR data showed that tprJ is expressed in treponemes during syphilitic infection. A putative tprJ gene was sequenced from T. pertenue, the closely related yaws agent. The deduced amino acid sequence of T. pertenue TprJ is 87.3% identical to that of T. pallidum TprJ. This is the first report of significant sequence differences within homologous genes of T. pallidum and T. pertenue.
    FEMS Microbiology Letters 11/1998; 169(1):155 - 163. · 2.04 Impact Factor
  • Article: The genome of Treponema pallidum: new light on the agent of syphilis
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    ABSTRACT: Treponema pallidum subsp. pallidum, the causative agent of the sexually transmitted disease syphilis, is a fastidious, microaerophilic obligate parasite of humans. This bacterium is one of the few prominent infectious agents that has not been cultured continuously in vitro and consequently relatively little is known about its virulence mechanisms at the molecular level. T. pallidum therefore represented an attractive candidate for genomic sequencing. The complete genome sequence of T. pallidum has now been completed and comprises 1 138 006 base pairs containing 1041 predicted protein coding sequences. An important goal of this project is to identify possible virulence factors. Analysis of the genome indicates a number of potential virulence factors including a family of 12 proteins related to the Msp protein of Treponema denticola, a number of putative hemolysins, as well as several other classes of proteins of interest. The results of this analysis are reviewed in this article and indicate the value of whole genome sequences for rapidly advancing knowledge of infectious agents.
    FEMS microbiology reviews 09/1998; 22(4):323 - 332. · 10.96 Impact Factor
  • Article: Identification and sequences of the Treponema pallidum fliM', fli Y, fliP, fliQ, fliR and flhB' genes
    John M. Hardham, Jonathan G. Frye, Lola V. Stamm
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    ABSTRACT: Information regarding the biology and virulence attributes of Treponema pallidum (Tp) is limited due to the lack of genetic exchange mechanisms and the inability to continuously cultivate this spirochete. We have utilized TnphoA mutagenesis of a Tp genomic DNA library in Escherichia coli (Ec) to identify genes encoding exported proteins, a subset of which are likely to be important in treponemal pathogenesis. We report here the identification and nucleotide (nt) sequence of a 5-kb treponemal DNA insert that contains seven open reading frames (ORFs). The proteins encoded by six of these ORFs have homology with members of a newly described protein family involved in the biogenesis/assembly of flagella and the control of flagellar rotation in Ec, Salmonella typhimurium (St) and Bacillus subtilis (Bs). Certain members of this family are also involved in the export of virulence factors in Yersinia (Yr) spp., St and Shigella flexneri (Sf). We have named these six ORFs fliM',fliY, fliP, fliQ, fliR and flhB'. The operon containing these ORFs has been designated as the fla operon. We hypothesize that the protein products of these genes are involved in the biogenesis/ assembly of flagella and the control of flagellar rotation in Tp.
    Gene.