Binding Affinity of Actinobacillus actinomycetemcomitans for extracellular matrix proteins

伴放线放线杆菌对细胞外基质蛋白的结合亲和力

基本信息

批准号：
17592190
负责人：
KAWATO Takayuki
金额：
$ 1.28万
依托单位：
Nihon University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

项目摘要

Actinobacillus actinomycetemcomitans is an aetiologic agent in the development of periodontal and some systemic diseases in humans. In this study, the binding affinity of A. actinomycetemcomitans to 4 kinds of extracellular matrix protein (collagen type I, collagen type IV, fibronectin, and laminin) was investigated. A. actinomycetemcomitansY4 and IDH781 bound to immobilized fibronectin and collagen type IV more than collagen type I and laminin. The binding of the cells to immobilized fibronectin and type IV collagen was inhibited by both of soluble fibronectin and collagen type N. The soluble fibronectin, but not the soluble collagen type IV bound to the 40-kDa proteins that were extracted from Y4 and IDH781 cells. These results suggest that Actinobacillus actinomycetemcomitansY4 and IDH781 have high binding affinity for fibronectin and this binding may be regulated with the 40-kDa bacterial cell proteins. Y4 and IDH781 also showed high affinity for collagen type IV and the non-protein component of bacterial cells may be involved in binding to collagen type IV.The cell surface protein antigen (PAg) and glucosyltransferases (GTFs) produced by Streptococcus sobrinus are major colonization factors of the organism, and the inhibition of these two factors should provide protection against dental caries. In this study, we constructed a fusion protein (PAgA-GB) composed of the alanine-rich region of PAg and the glucan-binding domain of GTF, and the antibodies against the fusion protein were prepared in rabbits. The antibody against PAgA-GB significantly inhibited the sucrose-dependent adhesion, but not sucrose-independent adhesion. These results show that the antibody against GTF-I may be useful for effective inhibition of the sucrose-dependent adhesion of S. sobrinus. However, PAg of S sobrinus may not function primarily as a receptor for acquired pellicles, and other cell surface proteins may be involved in the sucrose-independent adhesion of S sobrinus.

伴放线放线杆菌是人类牙周病和一些全身性疾病发展的病原体。在本研究中，研究了 A. actinomycetemcomitans 与 4 种细胞外基质蛋白（I 型胶原、IV 型胶原、纤连蛋白和层粘连蛋白）的结合亲和力。 A. actinomycetemcomitansY4 和 IDH781 与固定纤连蛋白和 IV 型胶原蛋白的结合多于与 I 型胶原蛋白和层粘连蛋白的结合。细胞与固定化纤连蛋白和 IV 型胶原的结合受到可溶性纤连蛋白和 N 型胶原的抑制。可溶性纤连蛋白（而非可溶性 IV 型胶原）与从 Y4 和 IDH781 细胞中提取的 40 kDa 蛋白质结合。。这些结果表明，Actinobacillus actinomycetemcomitansY4 和 IDH781 对纤连蛋白具有高结合亲和力，并且这种结合可能受到 40-kDa 细菌细胞蛋白的调节。 Y4和IDH781也表现出对IV型胶原蛋白的高亲和力，细菌细胞的非蛋白质成分可能参与与IV型胶原蛋白的结合。远缘链球菌产生的细胞表面蛋白抗原（PAg）和葡萄糖基转移酶（GTF）是主要定植生物体的因素，抑制这两个因素应该可以预防龋齿。在本研究中，我们构建了由PAg富含丙氨酸的区域和GTF的葡聚糖结合域组成的融合蛋白（PAgA-GB），并在兔体内制备了针对该融合蛋白的抗体。针对PAgA-GB的抗体显着抑制蔗糖依赖性粘附，但不抑制蔗糖非依赖性粘附。这些结果表明，针对GTF-I的抗体可用于有效抑制S. sobrinus的蔗糖依赖性粘附。然而，S sobrinus 的 PAg 可能主要不是作为获得性膜的受体，并且其他细胞表面蛋白可能参与 S sobrinus 的蔗糖独立粘附。