Identification of cyclic di-GMP signaling components in P. gingivalis

 说明书(申请人提供)：鉴定牙龈假单胞菌环状二聚体GMP(c-di-GMP)中的环二聚体GMP信号成分被认为是最常见的细菌第二信使之一。越来越多的证据表明，c-di-GMP调节细菌的细胞周期、分化、生物膜的形成和扩散以及毒力。C-di-GMP的重要特征之一是它是一种独特的第二信使，仅存在于细菌和低等真核生物中。从实用的角度来看，c-di-GMP信号通路的调控可能为控制细菌感染提供新的靶点。尽管c-di-GMP信号在细菌生物膜形成和分散中的作用引起了人们的极大兴趣，但对c-di-GMP信号在口腔细菌中的研究非常有限。最近，我们开始了牙龈卟啉单胞菌c-di-GMP信号转导的研究，这可能是因为没有一个基因被注释为编码二鸟苷环化酶。利用生物信息学工具，我们发现了一个含有GGDEF结构域的蛋白质，pGN_1932(以前被注释为保守的假设蛋白质)。我们这项应用的目的是确定环二GMP在牙龈假单胞菌细胞功能调节中的作用。我们推测c-di-GMP信号通过调节c-di-GMP水平及其代谢酶和受体，在控制牙龈假单胞菌生物被膜的形成和毒力方面发挥重要作用。为了验证这一假设，我们将首先确认一个可能的DGC蛋白(PGN_1932)的二鸟苷环化酶活性，并检验c-di-GMP浓度与表型产量的相关性，重点是牙龈假单胞菌的生物膜形成。我们将寻求验证c-di-GMP目标。我们实验室致力于了解牙龈假单胞菌中的c-di-GMP信号，因为它在细菌毒力，特别是在生物膜的形成和上皮细胞的侵袭中具有重要作用。对环状双GMP的研究将有助于更深入地理解牙龈假单胞菌是如何利用这种信号分子来响应环境刺激物以及与宿主细胞进行交流的。阐明c-di-GMP在牙龈假单胞菌致病中的作用，可能为开发防治生物被膜性牙周炎的新策略提供依据。

 DESCRIPTION (provided by applicant): Identification of cyclic di-GMP signaling components in P. gingivalis Cyclic dimeric GMP (c-di-GMP) has been considered as one of the most common bacterial second messengers. A growing body of evidence shows that c-di-GMP regulates bacterial cell cycle, differentiation, biofilm formation and dispersion, and virulence. One of important features of c-di-GMP is that it is a unique second messenger only found in bacteria and lower eukaryotes. From a practical standpoint, modulation of c- di-GMP signal pathways may provide a new target of controlling bacterial infection. Although there is a huge interest in c-di-GMP sweeping through microbiology, especially in the role of c-di-GMP signaling in bacterial biofilm formation and dispersion, the study of c-di-GMP signaling in oral bacteria is very limited. Recently, we have initiated investigation of c-di-GMP signaling in Porphyromonas gingivalis, likely due to none of genes is annotated encoding a diguanylate cyclase. Using bioinformatics tools, we found a protein containing a GGDEF domain with high certainty, PGN_1932 (previously annotated as a conserved hypothetical protein). Our objective of this application is to determine the role of cyclic di-GMP in regulation of cellular functions of P. gingivalis. We hypothesize that c-di-GMP signaling plays an important role in controlling biofilm formation and the virulence of P. gingivalis through regulation of c-di-GMP level, its metabolic enzymes and receptors. To test this hypothesis, we will first confirm the diguanylate cyclase activity of a putative DGC protein (PGN_1932) and examine correlation of the c-di-GMP concentration with phenotypic output, emphasizing on biofilm formation of P. gingivalis. We will seek to validate c-di-GMP targets. Our laboratory is committed to understanding c-di-GMP signaling in P. gingivalis because of its importance in the bacterial virulence, especially in bioflm formation and invasion of epithelial cells. The proposed studies on cyclic di-GMP will lead to a deeper understanding of how P. gingivalis use this signaling molecule to response to environmental stimulators and to communicate with host cells. Deciphering of the role of c-di-GMP in P. gingivalis pathogenicity may provide bases for developing new strategies of preventing and treating biofilm induced periodontitis.