유전자 특이성 기반 치주 질환 원인균 동정 및 분류

Abstract

Periodontal disease is a destructive, inflammatory disease of the supportive structures of the teeth and oral bacteria and their products are the causes of tissue destruction. So far about 600 species of oral microorganisms have been identified and other 200 species of microorganisms were detected in the oral cavity of the patients who were affected with periodontal disease. Among them, only about 10 species were identified as causative agents of periodontal diseases and these are mainly anaerobic, gram-negative bacteria. Periodontal pathogen should possess virulence factors relevant to the inflammation on periodontal tissue. The virulence factors of periodontal pathogens are composed of destructive factors to periodontal tissue and immuno-supressive factors of host. Because of the limits of the morphological classification of bacteria, the importance of the classification of oral microbial using genome sequences is gradually increased. Thus, the recent developments of molecular biology result in many researches about classification of oral microbial using genetic markers. But the database that integrates information from genetic sequences of periodontal pathogens is not sufficient. Therefore, this research included the construction of database system which integrates the genetic information of oral microbial. As a result, it compares the degree of genetic similarity with the species belonging to the database using the destructive virulence factors as genetic marker. The search system with the database, named as PPVF is accessible on the internet through the web site http://lcbb.snu.ac.kr/ppvf/. Among the results it should be noted that 13 species of oral microorganisms have been found as potential pathogens of periodontal disease. These are consisted of estimated periodontal pathogen in other studies and normal oral microflora of health population. Their own pathogenecity is very low but they are opportunistic pathogens. When the balance of the normal flora is broken in the mouth and abnormal host immune system occurs, their pathogenecity will become very strong. The results of this study revealed some potential periodontal pathogens among species, whose relevance with periodontal disease was previously remained uncertain. And this will provide basic information for accurate diagnosis and identification of causal relationships about periodontal disease. It is hoped that this research will be further developed for the practical use.