Novel small molecule biosynthetic gene clusters in Streptococcus mutans and virulence of dental caries

项目摘要 龋齿是一种全球性的传染病，影响着80%人口的生活。 严重的幼儿龋齿（SECC）是特别值得关注的，其特征是广泛的牙齿 蛀牙会严重影响六岁以下儿童的牙齿健康。这 构成重大的经济负担，可能对儿童的福祉产生巨大影响， 可能有助于以后的整体健康。变形链球菌是最常见的细菌 与SECC和早期儿童龋齿（ECC）的发生有关。生物合成基因簇 细菌中的BGC通常编码小分子和其他抗菌肽的基因。这 研究计划提出研究一种新的BGC（丁内酯-梯形混合物，BL-BGC）， S.从高龋风险人群中的变形链球菌，以确定其对S。变形菌毒力和存活率 性状初步数据表明，BL-BGC在龋齿中显著上调， 在最普遍的S.高龋齿风险研究人群中的变异人。的 假设是临床S.带有BL-BGC的变异株的毒力特性会增加 和致龋性。目的1研究临床沙门氏菌的表型特征。含有BL- 利用基因突变研究BGC与龋病关键毒力和生存性状的关系 和体内生物膜分析。目的2：确定BL-BGC对毒力表达的影响 基因和代谢产物。使用RNA测序和代谢组学分析的变形杆菌生物膜。目的 3将决定BL-BGC如何影响S。使用动物模型的变形菌定殖和毒力 龋齿。本研究将阐明BL-BGC在S.变形菌毒力和 在K99阶段的健身。代谢产物S.具有BL-BGC影响键的变异株 毒力性状将在R 00阶段进行纯化和表征， S.变形菌在龋齿发病中的作用。这种和其他BGC的表征可以 从而产生新的治疗靶点，旨在减少、逆转甚至预防SECC。K99阶段 该奖项将为额外的研究培训提供时间和支持， 合作，加强专业发展和提交出版物，导致 在R 00阶段成功过渡到独立的学术研究任命。本研究 在使用来自临床S的BGC方面是独特的。从高危龋齿人群中分离出的变异株 允许结果的临床转化和使用代谢组学鉴定BL-BGC 相关化合物/代谢物。这项研究将通过建立一个独立的职业道路， 利用分子生物学方法验证流行病学的多学科计划 协会，弥合这些领域和推进S的知识。变异菌在龋齿中的毒力。

Project Summary Dental caries is a global infectious disease impacting the lives of 80% of the human population. Severe early childhood caries (SECC) is of particular concern and characterized by extensive tooth decay that can dramatically affect the dental health of children under six years of age. This constitutes a significant economic burden, can have dramatic impact on the child’s well being and may contribute to overall health later in life. Streptococcus mutans is the bacterium most commonly associated with initiation of SECC and early childhood caries (ECC). Biosynthetic gene clusters (BGCs) in bacteria often encode genes for small molecules and other antimicrobial peptides. This research plan proposes to investigate a novel BGC (butyrolactone-ladderane hybrid, BL-BGC) of S. mutans from a high caries risk population to identify its impact on S. mutans virulence and survival traits. Preliminary data suggests the BL-BGC is significantly up regulated in dental caries and occurs in the most prevalent strain type of S. mutans within a high-caries risk study population. The hypothesis is that clinical S. mutans strains with the BL-BGC will have increased virulence properties and cariogenicity. Aim 1 will characterize phenotypes of clinical S. mutans strains containing the BL- BGC and their association with dental caries key virulence and survival traits using gene mutagenesis and in-vivo biofilm analysis. Aim 2 will determine the impact of BL-BGC on expression of virulence genes and metabolites in S. mutans biofilms using RNA-sequencing and metabolomics analysis. Aim 3 will determine the how BL-BGC impacts S. mutans colonization and virulence using animal models of dental caries. The proposed study will elucidate the role of BL-BGC in S. mutans virulence and fitness during the K99 phase. Metabolites produced by S. mutans with BL-BGC impacting key virulence traits will be purified and characterized in the R00 phase, providing new insights into S. mutans’ role in the pathogenesis of dental caries. Characterization of this and other BGCs may lead to new therapeutic targets designed to reduce, reverse, or even prevent SECC. The K99 phase of this award will provide the time and support for additional research training, building effective collaborations, enhancing professional development and submission of publications leading to a successful transition to an independent academic research appointment in the R00 phase. This study is unique in the use of BGCs from clinical S. mutans isolates from a high-risk caries population allowing for clinical translation of results and the use of metabolomics for identification of BL-BGC related compounds/metabolites. This study will enable an independent career path by establishing a multidisciplinary program utilizing molecular biology approaches to validate epidemiological associations, bridging these fields and advancing the knowledge of S. mutans virulence in caries.