Amylase binding and gene expression in S. gordonii

S. gordonii 中的淀粉酶结合和基因表达

• 批准号: 8711690
• 负责人: FRANK ANDREW SCANNAPIECO
• 金额: $ 21.94万
• 依托单位: STATE UNIVERSITY OF NEW YORK AT BUFFALO
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-04 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8711690
• 关键词: Address; Affect; Affinity; Amylases; Bacteria; Bacterial Adhesion; Bacterial Genes; Binding; Binding Proteins; Cells; Dental Plaque; Dental caries; Development; Disease; Ductal; Enzymes; Far-Western Blotting; Gene Expression; Gene Expression Regulation; Genes; Genetic; Genomics; Goals; Homologous Gene; Human; In Vitro; Knowledge; Lead; Light; Metabolism; Microbe; Microbial Biofilms; Mouth Diseases; Mucins; Oral; Oral cavity; Organism; Play; Precipitation; Proteins; Proteomics; Rattus; Role; Saliva; Salivary; Salivary Proteins; Signal Pathway; Streptococcus; Streptococcus gordonii; Streptococcus mitis; Systemic disease; Tissue-Specific Gene Expression; Tooth structure; Yeasts; analog; base; clinical application; comparative; disorder control; disorder prevention; in vivo; inhibitor/antagonist; microbial colonization; microbial community; mutant; novel; oral streptococci; prevent; promoter; protein function; response; saliva mediated; three dimensional structure; yeast two hybrid system

DESCRIPTION (provided by applicant): It is well known that salivary components can interact with microbes to influence their colonization of the oral cavity. One such interaction involves the abundant salivary enzyme, amylase, which binds specifically and with high affinity to commensal oral streptococci that are early colonizers of the saliva-coated tooth and numerous in supragingival dental plaque. Amylase-binding streptococci (ABS) colonize only hosts with detectable salivary amylase activity suggesting that amylase interactions modulate oral colonization by ABS and have an evolutionary basis. The ABS S. gordonii produces two amylase-binding proteins (ABPs) [AbpA (20-kDa) and AbpB (82-kDa) of Streptococcus gordonii. The binding of amylase to this species is dependent only on AbpA in S. gordonii (and likely its homologs in other species), and not on AbpB. In vitro studies found ABPs to play a role in bacterial adhesion and biofilm formation. Interestingly, AbpA defective S. gordonii mutants were able to colonize rat mouths as well as the parental strains, suggesting that additional bacterial factors are involved in colonization and survival in vivo. In light of these findings, we have considered potentially novel functions for these proteins. Preliminary studies suggest that amylase-binding to S. gordonii elicits differential gene expression in the bacterial cell. Thus, th Specific Aims of this proposal are to: 1: identify streptococcal components that interact with AbpA that may participate in a novel signaling pathway. 2: determine the three-dimensional structure of AbpA, identify amylase binding motifs and to address the evolutionary basis for the divergence of ABP gene sequence. 3: compare the global gene expression response of S. gordonii following binding of amylase to the response induced by the binding of whole- and ductal-saliva and other purified salivary components (such as mucins, sIgA, etc). Knowledge of saliva-mediated bacterial signaling pathways could have clinical application, for example by devising analog agents that serve as inhibitors or promoters of microbial colonization. Such agents may enable selective manipulation of bacterial colonization, and by extension, impact disease prevention or control. This knowledge could well extend beyond biofilm development in the oral cavity, with application to other microbial communities affecting systemic disease.

描述（由申请人提供）：众所周知，唾液成分可与微生物相互作用，影响其在口腔中的定植。一个这样的交互涉及 丰富的唾液酶，淀粉酶，其特异性结合并与口腔链球菌具有高亲和力，口腔链球菌是唾液覆盖的牙齿的早期定居者，并且在龈上牙菌斑中大量存在。淀粉酶结合链球菌（ABS）定植只有主机可检测唾液淀粉酶活性表明淀粉酶的相互作用调节口腔定植ABS和进化的基础。ABS S。格氏链球菌（Streptococcus gordonii）产生两种淀粉酶结合蛋白（ABPs）[AbpA（20-kDa）和AbpB（82-kDa）]。淀粉酶与该种的结合仅依赖于S. gordonii（以及可能在其他物种中的同源物），而不是AbpB。体外研究发现ABPs在细菌粘附和生物膜形成中发挥作用。有趣的是，AbpA缺陷型S.戈登氏菌突变体能够在大鼠口腔中定植，与亲本菌株一样，这表明在体内定植和存活中涉及另外的细菌因素。鉴于这些发现，我们已经考虑了这些蛋白质的潜在新功能。初步研究表明，淀粉酶与S。gordonii elevis在细菌细胞中的差异基因表达。因此，本提案的具体目的是：1：鉴定与AbpA相互作用的链球菌组分，其可能参与新的信号通路。第二章：确定AbpA的三维结构，确定淀粉酶结合基序，并解决ABP基因序列分歧的进化基础。3：比较S. gordonii，随后淀粉酶与由全唾液和导管唾液以及其他纯化的唾液组分（如粘蛋白、sIgA等）的结合诱导的应答结合。唾液介导的细菌信号传导途径的知识可能具有临床应用，例如通过设计用作微生物定殖的抑制剂或促进剂的类似物试剂。这样的试剂可以使得能够选择性地操纵细菌定殖，并且通过扩展，影响疾病预防或控制。这一知识可以很好地扩展到口腔中生物膜的发展之外，并应用于影响全身性疾病的其他微生物群落。