Ser/Thr protein kinase PknB as target to decrease Streptococcus mutans ecological

描述（由申请人提供）：蛀牙或龋齿是最常见的传染病之一，影响全世界十分之九的人，在贫困群体中发病率更高。口腔生物膜成员变形链球菌在龋齿病因学中的作用已经得到了很好的证实。因此，控制口腔生物膜中的变形链球菌水平将有利于口腔健康和预防龋齿的发展。本项目主要研究真核样丝氨酸/苏氨酸蛋白激酶PknB作为一种抗s。它们的目标。PknB是包膜相关胁迫的重要传感器，可触发相应的细胞反应，增强变形链球菌的抗逆性。最近，我们能够证明PknB缺陷菌株对生态胁迫的敏感性增加。本研究的目的是确定一种干扰PknB依赖的应激适应的最佳方法。在Aim 1中，我们建议确定pknB在生物膜生长背景下的表达水平和pknB的定位。通过这种方法，我们将获得关于变形链球菌生物膜特异性基因表达的重要信息，并确定PknB中可接近的结构靶点。在Aim 2中，我们还将鉴定下游PknB激酶底物，并确定磷酸化级联，以鉴定变形链球菌特异性PknB干扰的潜在额外细胞内靶点。这项研究将扩大对PknB依赖性调控的认识，并有助于开发可能的新治疗策略来预防龋齿。

DESCRIPTION (provided by applicant): Tooth decay or dental caries is one of the most common infectious diseases affecting nine out of ten individuals worldwide with higher rates among underprivileged groups. The role of oral biofilm member Streptococcus mutans in the etiology of dental caries has been well established. Management of S. mutans levels in the oral biofilm would therefore be beneficial for oral health and prevent caries development. This project focuses on the eukaryotic-like Ser/Thr protein kinase PknB as an anti-S. mutans target. PknB is an important sensor of envelope related stress and triggers a respective cellular response to increase S. mutans stress resistance. Recently, we were able to demonstrate the increased susceptibility of a PknB deficient strain towards ecological stress. The goal of the present study is to identify an optimal approach to interfere with PknB dependent stress adaptation. In Aim 1 we propose to determine the levels of pknB expression and localization of PknB in the context of biofilm growth. With this approach we will obtain important information about S. mutans biofilm specific gene expression and identify accessible structural targets in PknB. In Aim 2 we will also identify downstream PknB kinase substrates and determine the phosphorylation cascade to identify potential additional intracellular targets for S. mutans specific PknB interference. This study will expand the knowledge of PknB dependent regulation and help to develop possible novel therapeutic strategies to prevent caries. PUBLIC HEALTH RELEVANCE: Dental caries is a common infectious disease causing considerable discomfort in affected individuals. The etiological role of Streptococcus mutans in caries development has been well documented. This project investigates a specific component of S. mutans stress response with the goal of determining the optimal approach to interfere with the stress adaptation process. A detailed understanding of this process will provide important new information for S. mutans specific interventions to prevent dental caries.