This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Caimano, M. J.
Right arrow Articles by Radolf, J. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Caimano, M. J.
Right arrow Articles by Radolf, J. D.
Right arrowPubmed/NCBI databases
*Substance via MeSH

 Previous Article  |  Next Article 

Infection and Immunity, August 1999, p. 4072-4083, Vol. 67, No. 8
0019-9567/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

The Treponema denticola Major Sheath Protein Is Predominantly Periplasmic and Has Only Limited Surface Exposure

Melissa J. Caimano,1,dagger Kenneth W. Bourell,1,dagger Teresa D. Bannister,2 David L. Cox,3 and Justin D. Radolf1,4,*

Departments of Internal Medicine,1 Biochemistry,2 and Microbiology,4 University of Texas Southwestern Medical Center, Dallas, Texas 75235, and the Division of STD Laboratory Research, Centers for Disease Control and Prevention, Atlanta, Georgia 303333

Received 12 February 1999/Returned for modification 5 May 1999/Accepted 17 May 1999

The recent discovery that the Treponema pallidum genome encodes 12 orthologs of the Treponema denticola major sheath protein (Msp) prompted us to reexamine the cellular location and topology of the T. denticola polypeptide. Experiments initially were conducted to ascertain whether Msp forms an array on or within the T. denticola outer membrane. Transmission electron microscopy (EM) of negatively stained and ultrathin-sectioned organisms failed to identify a typical surface layer, whereas freeze-fracture EM revealed that the T. denticola outer membrane contains heterogeneous transmembrane proteins but no array. In contrast, a lattice-like structure was observed in vesicles released from mildly sonicated treponemes; combined EM and biochemical analyses demonstrated that this structure was the peptidoglycan sacculus. Immunoelectron microscopy (IEM) subsequently was performed to localize Msp in T. denticola. Examination of negatively stained whole mounts identified substantial amounts of Msp in sonicated organisms. IEM of ultrathin-sectioned, intact treponemes also demonstrated that the preponderance of antigen was unassociated with the outer membrane. Lastly, immunofluorescence analysis of treponemes embedded in agarose gel microdroplets revealed that only minor portions of Msp are surface exposed. Taken as a whole, our findings challenge the widely held belief that Msp forms an array within the T. denticola outer membrane and demonstrate, instead, that it is predominantly periplasmic with only limited surface exposure. These findings also have implications for our evolving understanding of the contribution(s) of Msp/Tpr orthologs to treponemal physiology and disease pathogenesis.

* Corresponding author. Present address: University of Connecticut Health Center, Center for Microbial Pathogenesis, 263 Farmington Ave., Farmington, CT 06030-3710. Phone: (860) 679-8129. Fax: (860) 679-8130. E-mail: Jradolf{at}up.uchc.edu.

dagger Present address: University of Connecticut Health Center, Center for Microbial Pathogenesis, Farmington, CT 06030-3710.

Infection and Immunity, August 1999, p. 4072-4083, Vol. 67, No. 8
0019-9567/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:

  • Nussbaum, G., Ben-Adi, S., Genzler, T., Sela, M., Rosen, G. (2009). Involvement of Toll-Like Receptors 2 and 4 in the Innate Immune Response to Treponema denticola and Its Outer Sheath Components. Infect. Immun. 77: 3939-3947 [Abstract] [Full Text]  
  • Lee, S.-H., Kim, J. S., Jun, H.-K., Lee, H.-R., Lee, D., Choi, B.-K. (2009). The Major Outer Membrane Protein of a Periodontopathogen Induces IFN-{beta} and IFN-Stimulated Genes in Monocytes via Lipid Raft and TANK-Binding Kinase 1/IFN Regulatory Factor-3. J. Immunol. 182: 5823-5835 [Abstract] [Full Text]  
  • Edwards, A. M., Jenkinson, H. F., Woodward, M. J., Dymock, D. (2005). Binding Properties and Adhesion-Mediating Regions of the Major Sheath Protein of Treponema denticola ATCC 35405. Infect. Immun. 73: 2891-2898 [Abstract] [Full Text]  
  • Hazlett, K. R.O., Sellati, T. J., Nguyen, T. T., Cox, D. L., Clawson, M. L., Caimano, M. J., Radolf, J. D. (2001). The Tprk Protein of Treponema pallidum Is Periplasmic and Is Not a Target of Opsonic Antibody or Protective Immunity. JEM 193: 1015-1026 [Abstract] [Full Text]  
  • Cox, D. L., Radolf, J. D. (2001). Insertion of fluorescent fatty acid probes into the outer membranes of the pathogenic spirochaetes Treponema pallidum and Borrelia burgdorferi. Microbiology 147: 1161-1169 [Abstract] [Full Text]  
  • Sela, M. N. (2001). Role of Treponema Denticola in Periodontal Diseases. CROBM 12: 399-413 [Abstract] [Full Text]  
  • Fenno, J. C., Tamura, M., Hannam, P. M., Wong, G. W. K., Chan, R. A., McBride, B. C. (2000). Identification of a Treponema denticola OppA Homologue That Binds Host Proteins Present in the Subgingival Environment. Infect. Immun. 68: 1884-1892 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»