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 Shipman, J. A.
Right arrow Articles by Salyers, A. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Shipman, J. A.
Right arrow Articles by Salyers, A. A.

 Previous Article  |  Next Article 

Journal of Bacteriology, December 1999, p. 7206-7211, Vol. 181, No. 23
0021-9193/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

Physiological Characterization of SusG, an Outer Membrane Protein Essential for Starch Utilization by Bacteroides thetaiotaomicron

Joseph A. Shipman,* Kyu Hong Cho, Hilary A. Siegel, and Abigail A. Salyers

Department of Microbiology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801

Received 10 May 1999/Accepted 14 September 1999

Results from previous studies had suggested that Bacteroides thetaiotaomicron utilizes starch by binding the polysaccharide to the bacterial surface and subsequently degrading the polymer by using cell-associated enzymes. Most of the starch-degrading activity was localized to the periplasm, but a portion appeared to be membrane associated. This raised the possibility that some breakdown might occur in the outer membrane prior to exposure of the polysaccharide to the periplasmic polysaccharide-degrading enzymes. In this study, we show that SusG, an outer membrane protein which has been shown genetically to be essential for starch utilization, has enzymatic activity. Results of protease accessibility experiments support the hypothesis that SusG is exposed on the cell surface. Results of [14C]starch binding assays, however, show that SusG plays a negligible role in binding of starch to the cell surface. Consistent with this, SusG has a relatively high Km for starch and by itself is not sufficient to allow cells to grow on starch or to bind starch. Hence, the main role of SusG is to hydrolyze starch, but the binding of starch to the cell surface is evidently mediated by other proteins presumably interacting with SusG.

* Corresponding author. Mailing address: Department of Microbiology, University of Illinois at Urbana-Champaign, 601 South Goodwin Ave., Urbana, IL 61801. Phone: (217) 244-2938. Fax: (217) 244-6697. E-mail: jshipman{at}uiuc.edu.

Journal of Bacteriology, December 1999, p. 7206-7211, Vol. 181, No. 23
0021-9193/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:

  • Wexler, H. M. (2007). Bacteroides: the Good, the Bad, and the Nitty-Gritty. Clin. Microbiol. Rev. 20: 593-621 [Abstract] [Full Text]  
  • Xie, G., Bruce, D. C., Challacombe, J. F., Chertkov, O., Detter, J. C., Gilna, P., Han, C. S., Lucas, S., Misra, M., Myers, G. L., Richardson, P., Tapia, R., Thayer, N., Thompson, L. S., Brettin, T. S., Henrissat, B., Wilson, D. B., McBride, M. J. (2007). Genome Sequence of the Cellulolytic Gliding Bacterium Cytophaga hutchinsonii. Appl. Environ. Microbiol. 73: 3536-3546 [Abstract] [Full Text]  
  • Ramsay, A. G., Scott, K. P., Martin, J. C., Rincon, M. T., Flint, H. J. (2006). Cell-associated {alpha}-amylases of butyrate-producing Firmicute bacteria from the human colon.. Microbiology 152: 3281-3290 [Abstract] [Full Text]  
  • Nikaido, H. (2003). Molecular Basis of Bacterial Outer Membrane Permeability Revisited. Microbiol. Mol. Biol. Rev. 67: 593-656 [Abstract] [Full Text]  
  • Cho, K. H., Cho, D., Wang, G.-R., Salyers, A. A. (2001). New Regulatory Gene That Contributes to Control of Bacteroides thetaiotaomicron Starch Utilization Genes. J. Bacteriol. 183: 7198-7205 [Abstract] [Full Text]  
  • Cho, K. H., Salyers, A. A. (2001). Biochemical Analysis of Interactions between Outer Membrane Proteins That Contribute to Starch Utilization by Bacteroides thetaiotaomicron. J. Bacteriol. 183: 7224-7230 [Abstract] [Full Text]  
  • Wang, J., Wang, G.-R., Shoemaker, N. B., Salyers, A. A. (2001). Production of Two Proteins Encoded by the Bacteroides Mobilizable Transposon NBU1 Correlates with Time-Dependent Accumulation of the Excised NBU1 Circular Form. J. Bacteriol. 183: 6335-6343 [Abstract] [Full Text]  
  • Shipman, J. A., Berleman, J. E., Salyers, A. A. (2000). Characterization of Four Outer Membrane Proteins Involved in Binding Starch to the Cell Surface of Bacteroides thetaiotaomicron. J. Bacteriol. 182: 5365-5372 [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»