Bacterial Proteinases in Periodontal Disease

描述（由申请人提供）：我们最近发现了一种新的蛋白质分泌途径（被提议为IX型分泌系统；T9SS），牙周病病原体，包括牙龈卟啉单胞菌，中普雷沃氏菌和连铸Tannerella forsythia分泌许多毒力因子。我们当前亲本R01的研究进展表明，存在3到5个新的必需成分参与牙龈卟啉卟啉分泌途径。有趣的是，大量新发现的基因以及已经报道的基因显然编码推定的整体外膜(OM) β -桶蛋白。T9SS分泌时需要几种β -桶状OM蛋白，这是T9SS独有的，并将这种OM易位装置与革兰氏阴性菌中其他八种已知的分泌系统区分开来。在本申请中，响应NOT-OD-09-058（通知标题：NIH宣布为竞争性修订申请提供恢复法案资金），我们将：(i)验证整体OM β桶蛋白的跨膜拓扑结构；（ii）研究牙龈蛋白酶分泌所必需的其他蛋白质的亚细胞位置；（iii）确定了牙龈假单胞菌、中间假单胞菌和连翘菌株依赖于T9SS的分泌组；（iv）初步表征了连翘菌株中具有独特结构域结构的蛋白酶，这些蛋白酶很可能是通过T9SS分泌的。

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.