Mallozzi Michael, Bozue Joel, Giorno Rebecca, Moody Krishna-Sulayman, Slack Alex, Cote Christopher, Qiu Dengli, Wang Rong, McKenney Peter, Lai Erh-Min, Maddock Janine R, Friedlander Arthur, Welkos Susan, Eichenberger Patrick, Driks Adam
Department of Microbiology and Immunology, Loyola University Medical Center, Maywood, IL, USA.
FEMS Microbiol Lett. 2008 Dec;289(1):110-7. doi: 10.1111/j.1574-6968.2008.01380.x.
Bacterial spores are encased in a multilayered proteinaceous shell, called the coat. In many Bacillus spp., the coat protects against environmental assault and facilitates germination. In Bacillus anthracis, the spore is the etiological agent of anthrax, and the functions of the coat likely contribute to virulence. Here, we characterize a B. anthracis spore protein, called Cotbeta, which is encoded only in the genomes of the Bacillus cereus group. We found that Cotbeta is synthesized specifically during sporulation and is assembled onto the spore coat surface. Our analysis of a cotbeta null mutant in the Sterne strain reveals that Cotbeta has a role in determining coat-surface morphology but does not detectably affect germination. In the fully virulent Ames strain, a cotbeta null mutation has no effect on virulence in a murine model of B. anthracis infection.
细菌芽孢被包裹在一层多层蛋白质外壳中，称为芽孢衣。在许多芽孢杆菌属物种中，芽孢衣可抵御环境侵害并促进芽孢萌发。在炭疽芽孢杆菌中，芽孢是炭疽病的病原体，芽孢衣的功能可能有助于其致病性。在此，我们对一种炭疽芽孢杆菌芽孢蛋白Cotbeta进行了表征，该蛋白仅在蜡样芽孢杆菌群的基因组中编码。我们发现Cotbeta在芽孢形成过程中特异性合成，并组装到芽孢衣表面。我们对斯特恩菌株中的cotbeta缺失突变体进行分析发现，Cotbeta在决定芽孢衣表面形态方面发挥作用，但对芽孢萌发没有明显影响。在完全有毒力的埃姆斯菌株中，cotbeta缺失突变对炭疽芽孢杆菌感染小鼠模型的毒力没有影响。
