Bordetella cell surface modification and pathogenesis

革兰氏阴性菌百日咳杆菌是一种人类限制性病原体， 呼吸道感染和百日咳或百日咳。尽管高水平和广泛的 接种疫苗后，世界范围内的B。百日咳感染和百日咳。这种复苏是 这归因于目前的无细胞百日咳疫苗在控制细菌数量方面的无效性。 鼻咽，细菌传播和产生短期免疫。怎么样B。百日咳存活 有效地在呼吸道和社区循环的了解甚少。为了控制 因此，发现新的策略和鉴定新的发病相关基因座至关重要 和因素。 在我们的实验室中鉴定的draABCD基因座在体外促进（i）对抗微生物药物杀灭的抗性， 肽和蛋白质（AMP）;（ii）多形核白细胞和（iii）生物膜的形成。我们 假设DRA对于B存活是关键的。小鼠呼吸道中的百日咳。具体目标1： 利用已建立的鼻内感染小鼠模型来检查其在定植和生物膜中的作用 在呼吸道器官中形成。我们还将测试DRA是否促进对呼吸道疾病的依从性， 上皮细胞系和呼吸道外植体。 Dra蛋白催化D-丙氨酸在外膜相关的蛋白酶敏感的 成分这种表面改性的机理与多糖改性不同 其他已知的细菌位点。Dra改性表面因子（DMF）未知。在具体目标2中，使用 分馏技术和质谱，我们将确定DMF。 这项工作将揭示新的毒力策略，为百日咳死灰复燃的原因提供信息。 对dra基因座的研究和发现DMF的身份将为生物化学和生物学研究提供重要的参考。 深入了解B中的表面变化。百日咳。本研究的结果 将导致靶向dra基因座和DMF，用于开发更好的疫苗和替代疗法。

The Gram-negative bacterium Bordetella pertussis is a human-restricted pathogen that causes severe respiratory infections and the disease whooping cough or pertussis. Despite high levels and widespread vaccination, there has been a world-wide rise in B. pertussis infections and pertussis. This resurgence is attributed to the ineffectiveness of the current acellular pertussis vaccines to control bacterial numbers in the nasopharynx, bacterial transmission and generation of shorter-lived immunity. How B. pertussis survives effectively in the respiratory tract and circulates in the community is poorly understood. In order to control the resurgence of pertussis, it is critical to discover new strategies and identify new pathogenesis-associated loci and factors. The draABCD locus identified in our laboratory promotes in vitro (i) the resistance to killing by anti-microbial peptides and proteins (AMPs); (ii) polymorphonuclear leukocytes and (iii) the formation of biofilms. We hypothesize that dra is critical for survival of B. pertussis in the mouse respiratory tract. In Specific aim 1, we will utilize well-established mouse models of intranasal infection to examine its role in colonization and biofilm formation in the respiratory tract organs. We will also test whether dra promotes adherence to respiratory epithelium by using epithelial cells lines and respiratory explants. The Dra proteins catalyze the addition of D-alanine in an outer membrane-associated protease-susceptible component. This mechanism of surface modification is distinct from the polysaccharide modification carried out by other known bacterial loci. The Dra-modified surface factor (DMF) is unknown. In Specific Aim 2, using fractionation techniques and mass spectrometry, we will identify the DMF. This work will uncover new virulence strategies that will inform on the reasons of the resurgence of pertussis. Studies of the dra locus and discovering the identity of the DMF will provide important biochemical and biological insights resulting in advanced understanding of surface alterations in B. pertussis. Outcomes from this research will result in targeting of the dra locus and DMF for developing better vaccines and alternative therapeutics.