P. gingivalis genes essential for tobacco smoke survival

项目摘要/摘要 牙周炎是一种高度流行的疾病，与几种使人衰弱的全身疾病有关， 包括血管和肺部疾病、糖尿病和早产。最新的流行病学 有证据表明，吸烟是#年破坏性牙周病病例的主要原因。 发达国家。吸烟增加了感染率，并增加了牙周一种关键病原体的数量， 牙龈卟啉单胞菌。然而，这种现象背后的机制还需要阐明。在……里面 在两年的NIGMS资助机制的推动下，第一次迭代奖励，我们产生了8万个殖民地 牙龈假单胞菌ATCC 33277菌株的转座子测序文库，并利用该资源： (I)成功地确定了256个假定对烟草诱导的应激生存至关重要的基因； (2)描绘烟草生存、上皮定植所普遍需要的“核心应激基因组” 和皮下脓肿的形成；以及 (Iii)确认几个基因对牙龈假单胞菌对香烟烟雾的生存是条件必需的- 通过产生单基因缺失突变体在体外诱导应激，这些突变体表现出 在烟熏培养基中与牙龈假单胞菌亲株进行绝对适合度分析； (Iv)我们还建立了一种新的烟草加重的牙周炎小鼠模型。 我们现在计划通过以下三个具体目标在这些成功的基础上再接再厉： 目的1：通过单基因突变进一步阐明牙龈假单胞菌CSE相关的生存策略 既是CSE必需的(TnSeq数据)；也是烟草管制的(RNAseq和qPCR)；但在 它们定植口腔上皮细胞的能力(TIGK模型)或免疫抵抗力(小鼠脓肿模型)。 目的2：通过小鼠烟雾暴露确定可能的CSE必需基因在体内的相关性 慢性Baker牙周炎模型中的小室模型。 目标3：通过确认生物功能，建立目标1和目标2中收集的数据的广泛适用性 CSE必需基因在多株牙龈假单胞菌中的分布。 长期的进展可能包括：(A)更好地了解牙龈假单胞菌是如何在 富含烟草毒素的环境；(B)控制牙龈假单胞菌的必需基因的未来治疗靶点 吸烟者中的感染(CSE--重要性数据)和一般情况(与多种疾病相关的情况、核心压力 基因组数据)；(C)根据对吸烟引起的机理的洞察，为吸烟者提供替代治疗方案 和/或加重牙周病；和(D)建立烟草基本基因数据库- 增强的病原体，将有助于识别烟草存活的常见细菌策略 因此，烟雾暴露扩大了这项研究的意义，超越了口腔。

PROJECT SUMMARY/ABSTRACT Periodontitis is a highly prevalent disease associated with several debilitating systemic conditions, including vascular and lung diseases, diabetes mellitus, and pre-term birth. The most recent epidemiological evidence suggests that tobacco smoking accounts for the majority of destructive periodontal disease cases in developed nations. Smoking enhances infection rates and enriches numbers of a key periodontal pathogen, Porphyromonas gingivalis. However, the mechanisms underlying this phenomenon are in need of elucidation. In the first iteration of award, facilitated by a two year NIGMS-funding mechanism, we generated an 80,000 colony transposon sequencing library for P. gingivalis strains ATCC 33277 and exploited this resource to: (i) Successfully identify 256 genes that are putatively essential for surviving tobacco-induced stress; (ii) Delineate a “core stress genome” commonly required for tobacco-survival, epithelial colonization and subcutaneous abscess formation; and (iii) Validated several genes as conditionally essential for P. gingivalis to survival of cigarette smoke- induced stress in vitro by generating single gene deletion mutants that exhibit either reduced absolute fitness in competition assays with the parental P. gingivalis strain in smoked medium; (iv) We have also generated a novel murine model of tobacco-exacerbated periodontitis. We now plan to build on these successes via three specific aims, as follow: Aim 1: Further elucidate P. gingival CSE-related survival strategies by generating mutants in single genes that are both CSE-essential (TnSeq data) ;and tobacco-regulated (RNAseq and qPCR); yet not compromised in their ability to colonize oral epithelial cells (TIGK model) or immune resistance (murine abscess model). Aim 2: Determine in vivo relevance of putatively CSE-essential genes using a murine smoke-exposure chamber model in a chronic Baker model of P. gingivalis-induced periodontitis. Aim 3: Establish the broad applicability of data gathered in Aims 1 and 2 by confirming biological function and distribution of CSE essential genes in multiple P. gingivalis strains. Long term advances are likely to include (a) A better understanding of how P. gingivalis thrives in a tobacco-toxin rich environment; (b) Future therapeutic targeting of essential genes to control P. gingivalis infection in smokers (CSE-essentiality data) and in general (multiple disease-relevant conditions, core stress genome data); (c) Alternate treatment regimens for smokers based on mechanistic insight into smoke-induced and/or exacerbated periodontal diseases;and (d) The establishment of an essential gene database for tobacco- enhanced pathogens that will facilitate the identification of common bacterial strategies for surviving tobacco smoke exposure, thus, broadening the significance of the research beyond the oral cavity.