Interspecies Streptococcal Antagonisms in Oral Biofilms

描述（由申请人提供）：候选人的背景是细菌遗传学、生物膜形成和细菌毒力。近期目标是为独立科学家的职业生涯做准备，并开发牙齿生物膜中细菌相互作用的模型。职业目标是成为一名研究口腔微生物生态学的独立科学家，作为排名学术教师。指导阶段将包括开发额外的技术技能，专题，教学和教学法，参与T32 MinnCREST计划，并在研讨会和会议上发表演讲。指导阶段将包括与UMN研究人员建立跨学科合作，这将在独立阶段扩展，主要重点是实现拟议的研究。环境：拟议的研究将在UMN牙科学院的M.C.博士实验室进行。Herzberg博士是链球菌生物学领域的著名专家，特别是在表面粘附蛋白、生物膜形成和链球菌的病理生理学方面。心内膜炎的血研究：S的作用。变形菌在龋齿病因学中的作用已经得到了很好的研究。S.变形菌存在于牙菌斑中，有超过70种细菌。事实上，在S.突变相关的微生物组可能决定牙菌斑的致龋潜力。这些相互作用包括基因表达的调节、种间共聚集和生长抑制。我们推测，口腔链球菌竞争的一部分，通过影响直接物理相互作用和/或代谢信号的拮抗或挑战物种的毒力基因表达。我们将模拟S的相互作用。变异链球菌和S. sanguinis，因为它们在牙菌斑中的相互排斥是众所周知的。为了验证我们的假设，即种间相互作用影响的结果之间的竞争S。mutans和S. sanguinis，我们将：（B）寻找与S.变异链球菌和S.（d）确定S. sanguinis相互影响的表达谱。变异链球菌和S.（c）进一步研究血吸虫毒力基因间的直接物理相互作用。mutans和S.用原子力显微镜观察血吸虫相关性：毒力因子将被表征为指定口腔生物膜中的种间竞争，有助于更好地理解和控制致龋S的过度生长。变异人

DESCRIPTION (provided by applicant): The Candidates background is in bacterial genetics, biofilm formation and bacterial virulence. The immediate goal is to prepare for a career as an independent scientist and to develop a model for bacterial interactions in the dental biofilm. The career objective is to become an independent scientist studying oral microbial ecology as ranked academic faculty. The mentored-phase will include the development of additional technical skills, topical, teaching and pedagogy, participation in the T32 MinnCResT program, and presenting in seminars and at conferences. The mentored phase will include establishment of interdisciplinary collaborations with researchers at UMN, which will be extended during the independent phase, when the main focus is the achievement of the proposed research. Environment: The proposed research will be performed at the School of Dentistry, UMN in the lab of Dr. M.C. Herzberg, a renowned expert in streptococcal biology especially in surface-adhesion proteins, biofilm development and the patho-physiology of S. sanguinis in endocarditis. Research: The role of S. mutans in the etiology of dental caries has been well investigated. S. mutans resides in the dental plaque with over 70 bacterial species. Indeed, interaction in the S. mutans-associated microbiome may determine the cariogenic potential of dental plaque. These interactions include modulation of gene expression, interspecies co-aggregation and growth inhibition. We hypothesize that oral streptococci compete in part by influencing virulence gene expression in the antagonized or challenged species by direct physical interactions and/or metabolic signaling. We will model interactions of S. mutans and S. sanguinis because their mutual exclusion in dental plaque is well-known. To test our hypothesis that interspecies interactions influence the outcome of the competition between S. mutans and S. sanguinis, we will: (a) Develop a dual-species biofilm model based on saliva coated hydroxyapatite; (b) Search for new genes involved in the interspecies interaction between S. mutans and S. sanguinis; (d) Determine the mutual influenced expression profile of S. mutans and S. sanguinis virulence genes; (c) Further characterize the direct physical interactions between S. mutans and S. sanguinis by atomic force microscopy. Relevance: Virulence factors will be characterized that specify inter-species competition in the oral biofilm, contributing to better understanding and control of the overgrowth of cariogenic S. mutans.