Staphylococcal Biofilm and Disease

描述（由申请人提供）：本项目的主要目的是提供对生物膜内eDNA生成（通过自溶）和加工（通过葡萄球菌核酸酶）的控制的更深入的了解。这些研究将集中在葡萄球菌生物膜内存在的各种微生态位，并定义影响生物膜发育过程中参与这些过程的基因表达的代谢和化学计量因素。这些研究将扩展我们的初步结果，验证S。金黄色葡萄球菌生物膜响应于对基因表达的环境和随机效应而产生不同的功能亚群。在测试这一假设，我们将建立和阐明不同的功能亚群在一个成熟的生物膜的功能作用。为了实现这些目标，我们将实现三个具体目标。第一个目标将利用各种转录和代谢探针，结合BioFlux微流体技术，研究生物膜发育过程中产生的代谢异质性及其对死亡和裂解的影响。第二个目标将研究生物膜发育过程中核酸酶表达的调控，重点关注Sae调控系统的作用，以及SaeP是eDNA传感器的新假设。第三个目标是在生物膜内建立劳动分工，并确定生物膜内不同亚群的功能作用，包括扩散、诱变和抗生素耐受性。总体而言，这些具体目标中描述的实验将依赖于高度协作的努力，以更深入地了解决定不同生物膜生态位代谢的环境和随机调控机制。除了提供对葡萄球菌生物膜固有的代谢过程的更完整的理解外，该项目还将促进细菌生物膜作为高度复杂的分化细胞群体的新兴观点，类似于多细胞生物体。

DESCRIPTION (as provided by applicant): The primary objectives of this project are to provide greater insight into the control of eDNA generation (through autolysis) and processing (via staphylococcal nuclease) within a biofilm. These studies will focus on the varied micro-niches that exist within a staphylococcal biofilm, and define the metabolic and stoichiometric factors that influence the expression of genes involved in these processes during biofilm development. The proposed studies will extend our preliminary results testing the hypothesis that S. aureus biofilm produces distinct functional subpopulations in response to environmental and stochastic effects on gene expression. In testing this hypothesis we will establish and elucidate the functional roles of different functional subpopulations within a mature biofilm. To achieve these goals, we will perform three specific aims. The first aim will utilize a variety of transcriptional and metabolic probes, in combination with BioFlux microfluidics technology, to investigate the metabolic heterogeneity that arises during biofilm development and its impact on death and lysis. The second aim will study the regulation of nuclease expression during biofilm development, focusing heavily on the role of the Sae regulatory system, and the novel hypothesis that SaeP is a sensor of eDNA. The third aim will establish a division of labor within a biofilm and define the functional roles of the different subpopulations within a biofilm, includig dispersal, mutagenesis, and antibiotic tolerance. Overall, the experiments described in these specific aims will rely on a highly collaborative effort to yield greater insight into the environmental and stochastic regulatory mechanisms that dictate the metabolism of different biofilm niches. In addition to providing a more complete understanding of the metabolic processes inherent to staphylococcal biofilm, this project will foster a burgeoning perspective of bacterial biofilm as a highly complex population of differentiated cells, akin to multicellular organisms.