Regulation of Surface Protein Presentation on Streptococcus gordonii

戈登链球菌表面蛋白呈递的调节

• 批准号: 9749996
• 负责人: MARK C HERZBERG
• 金额: $ 35.76万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9749996
• 关键词: Adhesions; Adhesives; Bacteria; Bacterial Adhesins; Binding; Biological; Cell Wall; Cell membrane; Cell surface; Cells; Complement; Cues; Data; Dependence; Down-Regulation; Environment; Eukaryotic Cell; Gene Expression; Genes; Genetic Transcription; Gram-Positive Bacteria; Hydroxyapatites; Integrins; Knowledge; MUC5B gene; Mammalian Cell; Measures; Mediating; Membrane Proteins; Microbial Biofilms; Modeling; Molecular Weight; Mucins; Organism; Output; Pathway interactions; Phosphorylation; Proteins; Receptor Signaling; Regulation; Reporting; Saliva; Salivary; Sentinel; Signal Transduction; Specific qualifier value; Specificity; Streptococcus gordonii; Structure; Surface; System; Testing; Work; commensal bacteria; comparative; experimental study; lipoteichoic acid; macromolecule; molecular mass; novel; prevent; protein expression; receptor; response; salivary mucins; sensor; transcriptome; virtual

Bacteria alter gene expression while adapting to their environments. In some cases, gene expression changes in response to contact with abiotic surfaces. We show that Streptococcus gordonii, a model Gram-positive commensal bacterium, appears to regulate surface protein presentation in response to specifically engaging MUC5B. During biofilm formation on MUC5B, presentation of SGO_0707 on the cell wall and down-regulation of SGO_0890 and SGO_1487 depend on an intramembrane two-component system (TCS) sensor (SGO_1180). We also report (preliminary data) that the well-studied paired adhesins, SspA and SspB (SspAB), is also required to signal for presentation of SGO_0707 and loss of SGO_0890 and SGO_1487. Somewhat promiscuous in specificity, SspAB binds MUC5B. Hence, SspAB may serve as a receptor to induce an outside-in signal. Since SspAB covalently attaches to the cell wall, the signal to the cell membrane is probably transduced by another associated macromolecule. S. gordonii lipoteichoic acid (LTA) binds high molecular weight mucins, interacts with cell wall proteins, and traverses the cell wall to intercalate with the outer leaflet of the cell membrane. Preventing D-alanylation of S. gordonii LTA causes altered presentation of surface proteins. These data suggest that LTA and SspAB are co-receptors for MUC5B, with LTA serving to transduce a signal to a TCS (SGO_1180 and SGO_1181) to change the surface proteins presented on S. gordonii. We hypothesize, therefore, that S. gordonii SspAB cooperates with LTA to serve as a model signal transducing receptor for MUC5B during biofilm formation. To test our hypothesis and satisfy criteria for an outside-in signaling receptor, we will (1) determine whether both SspA and SspB are required; (2) show whether LTA functions as a co-receptor; (3) characterize response regulator SGO_1181 for signaling and regulation; (4) determine whether the change in surface protein presentation involves transcriptional and post-translational mechanisms; and (5) determine whether SspAB and SGO_1180 signal through intersecting or parallel pathways by performing comparative transcriptome analysis. To characterize the output of receptor signaling (Aims 1-4), we will measure transcription of sentinel genes (i.e., SspA, SspB, SGO_0707, SGO_0890, SGO_1487 and SGO_1180), presentation of sentinel surface proteins (i.e., 0707, 0890, 1487), and 1180 phosphorylation dependence. These experiments will define outside-in signaling in S. gordonii in response to specific surface environmental cues, which had been previously been viewed as a feature of higher organisms. This knowledge could suggest how certain bacteria adapt to changing environments when they must adhere or die.

细菌在适应其环境时会改变基因表达。在某些情况下，基因 表达因与非生物表面接触而发生的变化。我们证明了链球菌 Gordonii是一种模型革兰氏阳性的共生细菌，似乎调节表面蛋白 响应特殊参与MUC5B的介绍。在MUC5B上的生物膜形成期间 SGO_0707在细胞壁上的介绍以及SGO_0890和SGO_1487的下调 取决于膜内两组分系统（TCS）传感器（SGO_1180）。我们也报告 （初步数据）还需要研究良好的配对粘合剂SSPA和SSPB（SSPAB） 呈现SGO_0707的信号以及SGO_0890和SGO_1487的损失。有些 SPAB在特异性上的混杂性结合了MUC5B。因此，SSPAB可以用作诱导的受体 外部信号。由于SSPAB共价附着在细胞壁上，因此信号到细胞壁上 膜可能被另一个相关的大分子转导。 S. Gordonii Lipoteichoic 酸（LTA）结合高分子量粘蛋白，与细胞壁蛋白相互作用，并遍历 细胞壁与细胞膜的外部小叶插入。防止S.的D-丙二醇化 Gordonii LTA导致表面蛋白的表现改变。这些数据表明LTA和 SSPAB是MUC5B的共受体，LTA用来将信号转换为TCS（SGO_1180 和SGO_1181）更改S. gordonii上呈现的表面蛋白。我们假设， 因此，S。GordoniiSspab与LTA合作作为模型信号传递 生物膜形成过程中MUC5B的受体。测试我们的假设和满足的标准 外部信号受体，我们将（1）确定是否需要SSPA和SSPB； （2） 显示LTA是否充当共受体； （3）表征响应调节器SGO_1181 信号传导和调节； （4）确定表面蛋白的变化是否涉及 转录和翻译后机制； （5）确定sspab和 SGO_1180通过相交或并行途径信号通过进行比较 转录组分析。为了表征受体信号的输出（目标1-4），我们将测量 前哨基因的转录（即SSPA，SSPB，SGO_0707，SGO_0890，SGO_1487和 SGO_1180），前哨表面蛋白的呈现（即0707，0890，1487）和1180 磷酸化依赖性。这些实验将在S. gordonii中定义外部信号传导 对特定表面环境线索的响应，以前已被视为 更高生物的特征。这些知识可以表明某些细菌如何适应变化 环境必须遵守或死亡。