Characterization of the Exosporium Basal Layer Protein BxpB of Bacillus anthracis
| Autor: | Christopher T. Steichen, Charles L. Turnbough, John F. Kearney |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Microbiology
Microbial Cell Biology Bacterial Proteins Cloning Molecular Molecular Biology Spores Bacterial chemistry.chemical_classification Membrane Glycoproteins Bacillaceae biology fungi Exosporium Gene Expression Regulation Bacterial Immunogold labelling Flow Cytometry biology.organism_classification Bacillales Recombinant Proteins Spore Bacillus anthracis Cell biology Nap Kinetics Biochemistry chemistry Glycoprotein Cell Division |
| Zdroj: | Journal of Bacteriology. 187:5868-5876 |
| ISSN: | 1098-5530 0021-9193 |
| DOI: | 10.1128/jb.187.17.5868-5876.2005 |
| Popis: | Bacillus anthracis spores, the cause of anthrax, are enclosed by a prominent loose-fitting structure called the exosporium. The exosporium is composed of a basal layer and an external hair-like nap. The filaments of the hair-like nap are apparently formed by a single collagen-like glycoprotein called BclA, whereas several different proteins form or are tightly associated with the basal layer. In this study, we used immunogold electron microscopy to demonstrate that BxpB (also called ExsF) is a component of the exosporium basal layer. Binding to the basal layer by an anti-BxpB monoclonal antibody was greatly increased by the loss of BclA. We found that BxpB and BclA are part of a stable complex that appears to include the putative basal layer protein ExsY and possibly other proteins. Previous results suggested that BxpB was glycosylated; however, our results indicate that it is not a glycoprotein. We showed that ΔbxpB spores, which lack BxpB, contain an exosporium devoid of hair-like nap even though the ΔbxpB strain produces normal levels of BclA. These results indicated that BxpB is required for the attachment of BclA to the exosporium. Finally, we found that the efficiency of production of ΔbxpB spores and their resistance properties were similar to those of wild-type spores. However, ΔbxpB spores germinate faster than wild-type spores, indicating that BxpB suppresses germination. This effect did not appear to be related to the absence from ΔbxpB spores of a hair-like nap or of enzymes that degrade germinants. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|