| Project/Area Number |
17390485
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Morphological basic dentistry
|
|---|
| Research Institution | Nihon University |
|---|
Principal Investigator |
HAMADA Shigeyuki Nihon University Advanced Research Institute for the Sciences and Humanities, Professor, 大学院総合科学研究科, 教授 (60028777)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
KAWABATA Shigetada Osaka University Graduate School of Dentistry, Professor, 大学院歯学研究科, 教授 (50273694)
NAKAGAWA Ichiro Tokyo University Institute of Medical Sciences, Associate Professor, 医科学研究所, 助教授 (70294113)
|
|---|
| Project Period (FY) |
2005 – 2006
|
| Project Status |
Completed (Fiscal Year 2006)
|
| Budget Amount *help |
¥15,300,000 (Direct Cost: ¥15,300,000)
Fiscal Year 2006: ¥5,300,000 (Direct Cost: ¥5,300,000)
Fiscal Year 2005: ¥10,000,000 (Direct Cost: ¥10,000,000)
|
|---|
| Keywords | Porpyromonas gingival is / fimbriae / vesicle / Streptococcus mutans / glucose side chain / genome / Multilocus sequencing typing |
|---|
| Research Abstract |
Dental plaque has the properties of a biofilm, similar to other biofilms found in the body and the environment. Modern molecular biological techniques have identified about 1000 different bacterial species in the dental biofilm, twice as many as can be cultured. Oral biofilms are very heterogeneous in structure. However, the relationship between the genomic information and the development of oral and periodontal diseases are still ambiguous. In this study, we focused on two theme, (1) Analysis of genomic variation of oral streptococci (2) Pathogenic mechanism of Porphyromonas gingivalis against oral epithelial cells.
(1) Analysis of genomic variation of oral streptococci
S. mutans strains have been classified into four serotypes (c, e, f, and k). However, little is known about the S. mutans population, including the clonal relationships among strains of S. mutans. We have developed a multilocus sequence typing (MLST) scheme for S. mutans. Eight housekeeping gene fragments were sequenced
… More
from each of 102 S. mutans isolates. We identified 92 sequence types in these 102 isolates, indicating that S. mutans contains a diverse population. No geographic specificity was identified. However, the distribution of the collagen-binding protein gene (cnm) and direct evidence of mother-to-child transmission were clearly evident. We also performed the whole genome sequencing of the S. mutans NN2025 strain, and its genome had an extensive genomic arrangement across the replicore.
(2) Pathogenic mechanism of Porphyromonas gingivalis against oral epithelial cells.
Porphyromonas gingivalis is a periodontal pathogen whose fimbriae are classified into six genotypes based on the diversity of the fimA genes encoding each fimbria subunit. It was suggested that P. gingivalis strains with type II fimbriae were more virulent than type I strains. The substitution of type I fimA with type II enhanced bacterial adhesion/invasion to epithelial cells, whereas substitution with type I fimA resulted in diminished efficiency. These results suggest that type II fimbriae are a critical determinant of P. gingivalis virulence. Less
|
