This Article Full Text Full Text (PDF) Other Versions of this Article: JB.00921-06v1 189/3/691    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Giorno, R. Articles by Driks, A. Search for Related Content PubMed PubMed Citation Articles by Giorno, R. Articles by Driks, A.

 Previous Article  |  Next Article 

Journal of Bacteriology, February 2007, p. 691-705, Vol. 189, No. 3
0021-9193/07/$08.00+0     doi:10.1128/JB.00921-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Morphogenesis of the Bacillus anthracis Spore

Department of Microbiology and Immunology, Loyola University Medical Center, Maywood, Illinois 60153,¹ Bacteriology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland 21702-5011,² Department of Biological, Chemical, and Physical Sciences, Illinois Institute of Technology, Chicago, Illinois 60616,³ Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109,⁴ Headquarters, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland 21702-5011⁵

Received 26 June 2006/ Accepted 1 November 2006

Bacillus spp. and Clostridium spp. form a specialized cell type, called a spore, during a multistep differentiation process that is initiated in response to starvation. Spores are protected by a morphologically complex protein coat. The Bacillus anthracis coat is of particular interest because the spore is the infective particle of anthrax. We determined the roles of several B. anthracis orthologues of Bacillus subtilis coat protein genes in spore assembly and virulence. One of these, cotE, has a striking function in B. anthracis: it guides the assembly of the exosporium, an outer structure encasing B. anthracis but not B. subtilis spores. However, CotE has only a modest role in coat protein assembly, in contrast to the B. subtilis orthologue. cotE mutant spores are fully virulent in animal models, indicating that the exosporium is dispensable for infection, at least in the context of a cotE mutation. This has implications for both the pathophysiology of the disease and next-generation therapeutics. CotH, which directs the assembly of an important subset of coat proteins in B. subtilis, also directs coat protein deposition in B. anthracis. Additionally, however, in B. anthracis, CotH effects germination; in its absence, more spores germinate than in the wild type. We also found that SpoIVA has a critical role in directing the assembly of the coat and exosporium to an area around the forespore. This function is very similar to that of the B. subtilis orthologue, which directs the assembly of the coat to the forespore. These results show that while B. anthracis and B. subtilis rely on a core of conserved morphogenetic proteins to guide coat formation, these proteins may also be important for species-specific differences in coat morphology. We further hypothesize that variations in conserved morphogenetic coat proteins may play roles in taxonomic variation among species.

Published ahead of print on 17 November 2006.

This article has been cited by other articles:

• Dowd, M. M., Orsburn, B., Popham, D. L. (2008). Cortex Peptidoglycan Lytic Activity in Germinating Bacillus anthracis Spores. J. Bacteriol. 190: 4541-4548 [Abstract] [Full Text]  
• Oliva, C. R., Swiecki, M. K., Griguer, C. E., Lisanby, M. W., Bullard, D. C., Turnbough, C. L. Jr., Kearney, J. F. (2008). The integrin Mac-1 (CR3) mediates internalization and directs Bacillus anthracis spores into professional phagocytes. Proc. Natl. Acad. Sci. USA 105: 1261-1266 [Abstract] [Full Text]  
• McKevitt, M. T., Bryant, K. M., Shakir, S. M., Larabee, J. L., Blanke, S. R., Lovchik, J., Lyons, C. R., Ballard, J. D. (2007). Effects of Endogenous D-Alanine Synthesis and Autoinhibition of Bacillus anthracis Germination on In Vitro and In Vivo Infections. Infect. Immun. 75: 5726-5734 [Abstract] [Full Text]  
• Thompson, B. M., Waller, L. N., Fox, K. F., Fox, A., Stewart, G. C. (2007). The BclB Glycoprotein of Bacillus anthracis Is Involved in Exosporium Integrity. J. Bacteriol. 189: 6704-6713 [Abstract] [Full Text]  
• Bozue, J., Moody, K. L., Cote, C. K., Stiles, B. G., Friedlander, A. M., Welkos, S. L., Hale, M. L. (2007). Bacillus anthracis Spores of the bclA Mutant Exhibit Increased Adherence to Epithelial Cells, Fibroblasts, and Endothelial Cells but Not to Macrophages. Infect. Immun. 75: 4498-4505 [Abstract] [Full Text]  
• Weaver, J., Kang, T. J., Raines, K. W., Cao, G.-L., Hibbs, S., Tsai, P., Baillie, L., Rosen, G. M., Cross, A. S. (2007). Protective Role of Bacillus anthracis Exosporium in Macrophage-Mediated Killing by Nitric Oxide. Infect. Immun. 75: 3894-3901 [Abstract] [Full Text]