Role of coaggregation among periodontopathic bacteria in formation of periodontopathic biofilm

牙周病细菌共聚集在牙周病生物膜形成中的作用

基本信息

批准号：
16591837
负责人：
ISHIHARA Kazuyuki
金额：
$ 1.79万
依托单位：
Tokyo Dental College
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2006
项目状态：
已结题

项目摘要

Objects : Periodontitis is caused by Gram-negative rods and spirochetes. Porphyromonas gingivalis is a major pathogen of chronic periodontal disease, This microorganism has a number of virulence factors, including fimbriae, lipopolysaccharides and proteases, and is often co-isolated with Tannerella forsythensis and Treponema denticola. The combination of these three microorganisms is known as the "red complex", and is thought to play an important role in the progression of chronic periodontitis. In this project, we investigated coaggregation and synergistic effects among these periodontopathic bacteria to clarify the underlying mechanisms of periodontopathic biofilm formation.Materials and Methods : Coaggregation between P.gingivalis ATCC 33277 and T.denticola ATCC 35405 was evaluated by absorbance at 660 nm in coaggregation buffer. To clarify which P.gingivalis ligands were involved in coaggregation, knockout mutants lacking gingipains and fimbriae were constructed. Synergistic effect … More s on biofilm formation were evaluated by using a two-compartment co-culture system incorporating a 0.4 m filter unit.Results and Discussion : Coaggregation reaction between P.gingivalis and T.denticola was decreased in the Mfa1 deficient mutant, kgp, RgpA and RgpB deficient mutant and Kgp, RgpA and HagA deficient mutant. These results indicated that gingipains and Mfa1 were involved in the coaggregation reaction. In particular, activity decreased significantly in the Kgp, RgpA and RgpB deficient strain and Kgp, RgpA and HagA deficient strain. In addition, coaggregation activity was observed in the Mfa1 FimA mutant. This suggests that the hemagglutinin/ahesion domains of gingipains and HagA play a key role in the coaggregation reaction. Using our two-compartment system, Fusobacterium nucleatum showed an approximately four-fold increase in biofilm formation in co-culture with P.gingivalis compared with that obtained with single culture alone. Taken together, these results suggest that the coaggregation reaction of P.gingivalis with other periodontopathogens is involved not only in the colonization of gingival crevicular biofilms, but also in the formation of periodontopathic biofilms. Less

对象：牙周炎是由革兰氏阴性杆菌和牙龈卟啉单胞菌引起的，它是慢性牙周病的主要病原体，这种微生物具有多种毒力因子，包括菌毛、脂多糖和蛋白酶，并且经常与福赛坦纳氏菌（Tannerella forsythensis）共同分离。这三种微生物的组合被称为“红色密螺旋体”。复合体”，并被认为在慢性牙周炎的进展中发挥重要作用。在本项目中，我们研究了这些牙周病细菌之间的共聚集和协同效应，以阐明牙周病生物膜形成的潜在机制。材料和方法：P.通过 660 nm 处的吸光度评估牙龈炎 ATCC 33277 和齿龈炎 T.denticola ATCC 35405为了阐明哪些 P.gingivalis 配体参与了共聚集，构建了缺乏牙龈蛋白酶和菌毛的敲除突变体，通过使用包含 0.4 m 过滤单元的两室共培养系统来评估对生物膜形成的协同效应。结果与讨论：Mfa1 缺陷突变体中 P.gingivalis 和 T.denticola 之间的共聚集反应减少， kgp、RgpA 和 RgpB 缺陷突变体以及 Kgp、RgpA 和 HagA 缺陷突变体这些结果表明，gingipains 和 Mfa1 参与了共聚集反应，特别是在 Kgp、RgpA 和 RgpB 缺陷菌株以及 Kgp、RgpA 和 Hagp 缺陷菌株中，活性显着降低。 HagA 缺陷菌株此外，在 Mfa1 FimA 突变体中观察到共聚集活性。这表明牙龈蛋白酶和 HagA 的血凝素/粘附结构域在共聚集反应中发挥着关键作用，使用我们的两室系统，与牙龈卟啉单胞菌共培养相比，具核梭杆菌的生物膜形成增加了约四倍。综合起来，这些结果表明牙龈卟啉单胞菌与其他牙周病原菌的共聚集反应不参与其中。仅在龈沟生物膜的定植中，而且在牙周病生物膜的形成中也较少。