Exploring the Ecological Roles of Mutanic Acid and Mutanicyclin; Two Novel Small Molecules Produced by Streptococcus mutans

探索突变酸和突变环素的生态作用；

• 批准号: 9889108
• 负责人: Karen E. Nelson
• 金额: $ 29.25万
• 依托单位: J. CRAIG VENTER INSTITUTE, INC.
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9889108
• 关键词: Acids; Affect; Agar; Anti-Bacterial Agents; Antimicrobial Effect; Biological Assay; Biological Models; Child; Chronic Disease; Communities; Dental Care; Dental Enamel; Dental Plaque; Dental caries; Development; Disease; Ecology; Economic Burden; Ecosystem; Environment; Etiology; Future; Gene Cluster; Gene Expression; Genes; Genetic Transcription; Goals; Growth; Image; In Vitro; Interdisciplinary Study; Knowledge; Laboratory Research; Lactobacillus reuteri; Lead; Maps; Mass Spectrum Analysis; Medical; Metabolism; Microbial Biofilms; Minimum Inhibitory Concentration measurement; Modeling; Molecular; Monitor; Natural Products; Operon; Oral; Organism; Pathogenesis; Pathway interactions; Peptides; Phenotype; Population; Positioning Attribute; Preventive measure; Production; Regulation; Research; Role; Streptococcus; Streptococcus mitis; Streptococcus mutans; Streptococcus oralis; Streptococcus pyogenes; Streptococcus sanguis; Structure; Taxonomy; Techniques; Technology; Thick; Time; Transcriptional Regulation; Virulence; Virulence Factors; Virulent; Work; amidase; antimicrobial; deletion analysis; dental agent; early childhood; insight; interest; liquid chromatography mass spectrometry; microbial; microbiome; mutant; novel; novel therapeutics; oral bacteria; oral biofilm; oral microbiome; oral streptococci; organic acid; reutericyclin; small molecule; social; success; sugar; tooth surface; transcriptome sequencing

Project Summary Dental caries is the most common chronic disease, globally, is associated with a tremendous economic burden, and disproportionally affects populations least able to access dental care and afford treatment. Streptococcus mutans (Smu) is a common constituent of dental plaque, and the primary etiologic agent of dental caries. Smu causes disease by forming robust biofilms on the tooth surface and producing organic acids which dissolve the underlying tooth enamel. To persist in the dental plaque community and cause disease, Smu must be able to directly outcompete commensal organisms. Our research group recently identified the small molecules mutanic acid (MTA), mutanicyclins (MTC) A-C and their biosynthetic gene cluster (mta BGC) in several globally distributed Smu strains, including B04Sm5, which was isolated from a child with severe early childhood caries. B04Sm5, and MTC A specifically, had significant antimicrobial effects on other oral bacteria. In addition, B04Sm5 produced a more acidic local environment than the Smu paradigm strain, UA159, and this phenotype was dependent on a functional mta BGC. The overarching goal of this proposal is to determine the role of MTA and MTCs in Smu ecology and virulence. We propose an interdisciplinary research approach with two specific aims: Aim 1: Functional insights of the mta BGC and its products MTA and MTCs. MTA and MTC(s) production and regulation will be characterized by liquid chromatography mass spectrometry and RNA-seq analysis of deletion mutants of mta BGC genes. Next, the spectrum of activity of MTA and MTCs will be explored utilizing imaging mass spectrometry (IMS) of competition assays pitting B04Sm5, or the ΔmtaD mutant strain, which does not produce MTA or MTCs, against other oral bacteria. IMS will also be used to identify additional small molecules pertinent to the interspecies competitions. Aim 2: Determine the impacts of MTA, MTC A-C, and mta encoding Smu on oral biofilm virulence and community function. The effects of purified MTA, MTCs, as well as MTA/MTC producing strains of Smu, on oral microbial ecology and biofilm virulence will be explored using our established in vitro oral biofilm model, featuring over 100 taxa, and downstream meta-OMICS analyses. Changes in community virulence via acid production and biofilm formation will also be monitored. The proposed study provides a unique opportunity to expand our knowledge of the role of BGCs in the oral microbiome, which is severely lacking, and specifically elucidate a novel virulence pathway in Smu. This research will significantly increase our understanding of the pathogenesis of caries, which represents a tremendous global medical burden, and is likely to guide development of new therapeutics and preventative measures.

项目概要 龋齿是全球最常见的慢性疾病，带来巨大的经济负担， 并且对最无力获得牙科护理和负担得起链球菌治疗的人群造成不成比例的影响。 变形链球菌 (Smu) 是牙菌斑的常见成分，也是龋齿的主要病因。 通过在牙齿表面形成坚固的生物膜并产生溶解牙齿的有机酸来引起疾病 为了在牙菌斑群中持续存在并引起疾病，Smu 必须能够 我们的研究小组最近发现了小分子突变体。 酸 (MTA)、变环素 (MTC) A-C 及其生物合成基因簇 (mta BGC) 在全球多个地区 分发的 Smu 菌株包括 B04Sm5，它是从患有严重儿童早期龋齿的儿童中分离出来的。 B04Sm5，特别是MTC A，对其他口腔细菌具有显着的抗菌作用。 产生了比 Smu 范式菌株 UA159 更酸性的局部环境，并且这种表型是 依赖于功能性 mta BGC 该提案的总体目标是确定 MTA 和 BGC 的角色。 Smu 生态学和毒力中的 MTC 我们提出了一种跨学科研究方法，有两个具体目标： 目标 1：mta BGC 及其产品 MTA 和 MTC 生产的功能见解。 和调控将通过液相色谱质谱法和 RNA-seq 分析来表征 接下来，将利用 mta BGC 基因的缺失突变体来探索 MTA 和 MTC 的活性谱。 竞争分析的成像质谱 (IMS) 分析 B04Sm5 或 ΔmtaD 突变株， 不产生MTA或MTCs，IMS也将用于识别其他口腔细菌。 目标 2：确定 MTA、MTC A-C 和的影响。 编码 Smu 的 mta 对口腔生物膜毒力和群落功能的影响。 以及产生 MTA/MTC 的 Smu 菌株对口腔微生物生态学和生物膜毒力的影响将被探讨 使用我们建立的体外口腔生物膜模型，具有 100 多个分类群和下游元组学 还将监测酸产生和生物膜形成引起的群落毒力变化。 拟议的研究提供了一个独特的机会来扩展我们对 BGC 在口腔中的作用的了解。 这项研究严重缺乏微生物组，并专门阐明了 Smu 中的一种新的毒力途径。 将显着增加我们对龋齿发病机制的了解，这代表着全球巨大的 医疗负担，并可能指导新疗法和预防措施的开发。