【作者】 孔建明；

【导师】 项春生； 张传溪；

【作者基本信息】 浙江大学 ， 生物化学与分子生物学， 2010， 硕士

【摘要】 口腔微生物在维持口腔内环境稳定上起非常重要的作用。龋病是非常常见的一种牙齿疾病,特别是在幼儿期。然而对于患有龋病的儿童口腔内微生物整个菌群结构和动力学研究至今仍未被清晰的阐明。在本实验中,利用PCR-DGGE与454高通量焦磷酸测序技术相结合,对患有龋病儿童(CAC,下同)和无龋病儿童(CFC,下同)口腔内的微生物菌群进行多样性的比较分析。收集这些儿童的唾液和牙菌斑,提取DNA。设计通用引物测序扩增16S rDNA基因V3变异区进行测序和DGGE分析。测序总计得到186787条序列和41905个单一序列,经鉴定细菌来源10个门的200多个属。研究结果显示来自CFC和CAC的细菌可以聚成两个簇和若干个种型,在龈上菌斑中Streptococcus(连锁状球菌属),Veillonella(韦荣球菌属),Actinomyces(放线菌属),Granulicatella(颗粒链菌属),Leptotrichia(纤毛菌属)和Thiomonas(硫单胞菌属)与龋病有关,这些细菌相互作用,逐渐破坏生态平衡,最终导致龋病的发生。我们无法找到一个单一的致病菌但是发现了对龋病发生有着显著相关的致病菌群,而且这些致病菌群有可能成为干预龋病发生的目标。更多还原

【Abstract】 Oral microbiota plays a vital role in maintaining the homeostasis of oral cavity. Dental caries are among the most common diseases in children.Pathogenic bacteria contribute to the development of the disease.However,the overall structure and dynamics of bacterial communities in oral cavity from children with dental caries have not been explored deeply heretofore.In this study,we examined the bacterial diversity of oral microbiota from children with caries in comparison to those from caries-free children using PCR-DGGE and high-throughput barcoded pyrosequencing. Saliva and supragingival plaque samples were collected from 60 children.DNA was isolated from these samples and the hyper-variable V3 region of 16S rDNA genes was amplified using universal primers.A total of 186 787 sequences were obtained and 41 905 unique sequences represented all domains in our study.More than 200 genera belonging to 10 phyla were identified.Our data showed that the oral microbiota in saliva and supragingival plaques could be divided into two clusters and several phylotypes that were significantly different between the two patient groups.The genera of Streptococcus,Veillonella, Actinomyces,Granulicatella,Leptotrichia and Thiomonas in supragingival plaques were associated with dental caries.These genera interacted with each other intimately and changes the composition of the bacterial population destroyed the eubiosis of the microcosm gradually and contributed to the development of dental caries.There was no one specific pathogen but pathogenic communities that correlated with dental caries significantly.And theses pathogenic communities might provide additional targets for dental caries intervention.更多还原