Bacterial Proteinases in Periodontal Disease

描述(申请人提供)：我们最近发现了一种新的蛋白质分泌途径(建议为IX型分泌系统；T9SS)，用于牙周病原体，包括牙龈卟啉单胞菌、中间普雷沃特氏菌和连翘坦纳氏菌分泌多种毒力因子。我们目前的父母R01赠款的进展表明，存在3到5个新的必需成分，参与牙龈假单胞菌利用的牙龈疼痛分泌途径。有趣的是，大量新发现的基因和那些已经报道的基因显然编码假定的完整外膜(OM)β桶蛋白。T9SS对几种β-桶OM蛋白的分泌需求是独一无二的，这使该OM转位装置有别于革兰氏阴性细菌中其他八种已知的分泌系统。在本申请中，响应NOT-OD-09-058(通知标题：NIH宣布恢复法案资金可用于竞争性修订应用)，我们将：(I)验证整合型OMβ-Barrel蛋白的跨膜拓扑；(Ii)调查牙痛分泌所必需的其他蛋白质的亚细胞位置；(Iii)确定依赖于T9SS的牙龈假单胞菌、中间假单胞菌和连翘的分泌组；(Iv)对具有独特结构域结构的连翘蛋白酶进行初步鉴定，这些蛋白很可能是通过T9SS分泌的。 公共卫生相关性：这些拟议的研究结果将提供有关连翘独特的蛋白酶的重要信息，这些酶可能作为毒力因子发挥作用，并为牙龈假单胞菌、连翘和中间连翘的蛋白质分泌提供一条新的途径。这一见解可能会使抗体或化合物的设计能够阻止主要牙周病原体的多种毒力因子的输出，从长远来看，这可能会彻底改变牙周病的治疗和预防。

DESCRIPTION (provided by applicant): We have recently identified a novel protein secretion pathway (proposed to be a Type IX Secretion System; T9SS) employed by periodontopathogens, including Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia to secrete a number of virulence factors. Progress on our current parent R01 grant has revealed the presence of 3 to 5 new essential components participating in the gingipains secretion pathway utilized by P. gingivalis. Interestingly, a large number of the newly identified genes along with those already reported apparently encode for putative integral outer membrane (OM) beta-barrel proteins. The requirement of several beta-barrel OM proteins for secretion is unique for T9SS and sets this OM translocation apparatus apart from eight other known secretion system in Gram-negative bacteria. In this application, responding to NOT-OD-09-058 (Notice Title: NIH Announces the Availability of Recovery Act Funds for Competitive Revision Applications) we will: (i) verify transmembrane topology of integral OM beta-barrel proteins; (ii) investigate the subcellular location of other proteins essential for gingipains secretion; (iii) determine the secretome of P. gingivalis, P. intermedia and T. forsythia which is dependent on T9SS, (iv) perform an initial characterization on proteases of T. forsythia bearing unique domain structure, which are most likely secreted via T9SS. PUBLIC HEALTH RELEVANCE: The results of these proposed studies should yield important information on unique proteases of T. forsythia which may function as virulence factors and shade light on a novel pathway for the protein secretion by P. gingivalis, T. forsythia and P. intermedia. This insight may enable the design of antibodies or chemical compounds to block the export of multiple virulence factors from major periodontopathogens, which in the long term, may revolutionize treatment and prophylaxis of periodontal disease.