Probing the role of sensory cues in the regulation of bacterial biofilm development

项目总结 细菌具有非凡的能力，能够感知不同的刺激，并做出调节决定，以获得适当的 回应。我们研究计划的目标是了解这种细胞的分子基础。 在开发三维(3D)结构化社区期间的决策过程，称为 生物膜。生物膜代表着一种主要的细菌生活方式，对于抗菌素耐受性、毒力、 以及环境对多种病原体的持久性，包括多重耐药的铜绿假单胞菌。 铜绿假单胞菌是我们生物被膜基础研究的理想的临床相关模型系统，因为它 在各种各样的环境中适应并形成生物膜，其中的生物膜基质成分 有机体都有很好的特征。这项拟议的研究的首要目标是确定细菌如何解码 并在生物膜的发育过程中整合感官线索--物理、化学和生物 周而复始。我的工作表明，通过细菌光敏色素BphP光感受器检测到的光(物理线索) 通过RhlR介导的群体感应检测介导的光感应和种群密度(生物线索) 抑制生物膜。此外，我们还发现，营养物质的有效性(化学线索)与 群体感应(生物线索)以控制生物膜基质成分和结构。在接下来的五年， 我们将在我们最新发现的基础上，使用结合细菌遗传学的多学科方法， 分子生物学、生物化学、荧光显微镜、数学建模、结构生物学和 基因组规模的研究，以定义在不断增长的生物膜背景下的感觉信号。首先，我们将调查 光在异质生物膜中的局部和全局感知以及BphP光敏的特征 了解铜绿假单胞菌光感应调控的信号系统(项目1)。第二，我们将 解剖CbrA-CRC营养传感途径，了解营养供应如何控制生物膜的发育 (项目2)。第三，我们将描述RhlR介导的群体感应抑制生物膜的不同方式 编组(项目3)。最后，我们将定义来自两个或更多不同感觉信号通路的信息是如何 结合在集体行为的控制中(项目4)。我们的研究将建立一个广泛相关的 用于理解在不同感觉输入中编码的信息是如何被提取和集成到 推动集体行为-对于设计成功的综合战略以增强或 抑制生物被膜和开发新的治疗干预措施。

PROJECT SUMMARY Bacteria have a remarkable ability to sense diverse stimuli and make regulatory decisions to elicit an appropriate response. The objective of our research program is to understand the molecular underpinnings of this cellular decision-making process during the development of three dimensional (3D) structured communities called biofilms. Biofilms represent a predominant bacterial lifestyle and are crucial for antimicrobial tolerance, virulence, and environmental persistence in diverse pathogens including multi-drug resistant Pseudomonas aeruginosa. P. aeruginosa serves as an ideal clinically relevant model system for our basic research in biofilms because it adapts to and forms biofilms in a wide variety of environments, and the biofilm matrix components in this organism are well characterized. The overarching goal of the proposed research is to define how bacteria decode and integrate sensory cues – physical, chemical and biological – over the course of the biofilm development cycle. My work has shown that light (physical cue) detected via bacteriophytochrome BphP photoreceptor mediated photo sensing and population density (biological cue) detected via RhlR mediated quorum sensing represses biofilms. Furthermore, we have discovered that nutrient availability (chemical cue) converges with quorum sensing (biological cue) to control biofilm matrix components and architecture. Over the next five years, we will build on our recent discoveries and use a multidisciplinary approach combining bacterial genetics, molecular biology, biochemistry, fluorescence microscopy, mathematical modeling, structural biology and genome-scale studies to define sensory signaling in the context of a growing biofilm. First, we will investigate how light is perceived locally and globally in heterogenous biofilms and characterize the BphP photo-sensing signaling system to understand the regulation of photo sensing in P. aeruginosa (Project 1). Second, we will dissect the CbrA-Crc nutrient-sensing pathway to learn how nutrient availability controls biofilm development (Project 2). Third, we will delineate the different ways by which RhlR mediated quorum sensing represses biofilm formation (Project 3). Finally, we will define how information from two or more distinct sensory signaling pathways are combined in the control of collective behaviors (Project 4). Our research will establish a broadly relevant framework for understanding how information encoded in diverse sensory inputs is extracted and integrated to drive collective behaviors – knowledge that is crucial for designing successful synthetic strategies to enhance or to inhibit biofilms and for developing novel therapeutic interventions.