Research Of Virome In Dental Plaque Of Chronic Periodontitis Patients Based On Viral Metagenomics And Primary Study Of One Strain Of Bacteriophage

Periodontal diseases,which could wreck the periodontal tissue and contribute to many systemic diseases,possesses a widespread incidence in China.Traditional etiology research has identified bacteria as the main risk factor for periodontal diseases,while the bacterial infection theory can not explain all the clinical characteristics of periodontal diseases.Recently,the research of virus as periodontal pathogenic factor has attracted much attention.Once confirmed,the relevant evidence may completely subvert the current strategies on periodontal diseases' diagnosis,treatment and prevention.However,since the the virus communities in periodontal environment is so complex,traditional virus identification technology can no longer meet the needs.Viral metagenomics technology,which can excavate the virome and novel viruses information without the known sequences,is a new technology developed in recent years.Based on this,using viral metagenomic,high troughput sequencing technology,bioinformatics et al,in this programme we made a deep analysis of the virome in 30 pooled dental plaque samples from 150 patients with chronic periodontitis.Most of the sequences were aligned to double stranded DNA virus familiy: Human Herpes Virus,Taterpox virus,Glypta fumuferanae ichnovirus,Monkeypox virus.Also some sequences were aligned to double stranded RNA family: Human coxsackievirus B3,Midway virus,Nyamanini virus and bacteriophage family: Rhodococcus phage,Mycobacteriophage,Gordonia phage.We screened out a potential pathogenic bacteriophage,and cloned part of the genome by inverse polymerase chain reaction and genome walking methods.Sequence alignment identified the found sequence as Rhodococcus phage.We then discovered the detection rate differences of the found sequence between chronic periodontitis patients and periodontal healthy volunteers by epidemiological survey and analysis.To have a deep look into the structure and function of the found bacteriophage,we have attempted to isolate and culture the bacteriophage in vitro.This work did not succeed for the deficiency of host bacteria strains.Results of this programme revealed the virome information in periodontal environment,found Rhodococcus phage in human oral cavity for the first time,and established foundation for the diagnosing,treatment and prevention of periodontal diseases.