Candida albicans has been detected in root carious lesions. The current study aimed to explore the action of this fungal species on the microbial ecology and the pathogenesis of root caries. Here, by analyzing C. albicans in supragingival dental plaque collected from root carious lesions and sound root surfaces of root-caries subjects as well as caries-free individuals, we observed significantly increased colonization of C. albicans in root carious lesions. Further in vitro and animal studies showed that C. albicans colonization increased the cariogenicity of oral biofilm by altering its microbial ecology, leading to a polymicrobial biofilm with enhanced acidogenicity, and consequently exacerbated tooth demineralization and carious lesion severity. More importantly, we demonstrated that the cariogenicity-promoting activity of C. albicans was dependent on PHR2. Deletion of PHR2 restored microbial equilibrium and led to a less cariogenic biofilm as demonstrated by in vitro artificial caries model or in vivo root-caries rat model. Our data indicate the critical role of C. albicans infection in the occurrence of root caries. PHR2 is the major factor that determines the ecological impact and caries-promoting activity of C. albicans in a mixed microbial consortium.

白色念珠菌已在根龋病变中检测到。目前的研究旨在探索这种真菌对微生物生态学的作用和根龋的发病机制。在这里，通过分析从根龋病灶和根龋受试者以及无龋个体的健全根面收集的龈上牙菌斑中的白色念珠菌，我们观察到白色念珠菌在根龋病灶中的定植显着增加。进一步的体外和动物研究表明，白色念珠菌定植通过改变其微生物生态学增加了口腔生物膜的致龋性，导致具有增强的产酸性的多微生物生物膜，从而加剧了牙齿脱矿质和龋齿病变的严重程度。更重要的是，我们证明了白色念珠菌的促龋活性依赖于PHR2。PHR2的删除恢复了微生物平衡并导致较少的生龋生物膜，如体外人工龋齿模型或体内根龋大鼠模型所证明的那样。我们的数据表明白色念珠菌感染在根龋发生中的关键作用。PHR2是决定生态影响和促龋活性的主要因素混合微生物群中的白色念珠菌。