Collaborative Research: H-NOX homologues in biofilm formation: A combined molecular and systems level approach.

生物膜是附着在各种表面上的固定细菌群落。生物膜的栖息通常使细菌对清除策略产生抗性，而清除策略对它们的自由生物（浮游生物）对手是有效的。因此，了解促进在固定和不受束缚的生活方式之间转换的分子线索，可以指导我们在有益和有害的环境下对生物膜形成的反应。该项目旨在在系统水平上描述伴随生物膜形成的细胞变化，以及在分子水平上特定传感器蛋白家族在生物膜形成/溶解中的作用。培养学生是这项工作的重点。学生将由具有不同技术专长的科学家团队共同指导，并将有机会在国家实验室进行变革性研究。此外，还将为研究生开设蛋白质组学研习班，培养下一代科学家。科学目标是使用先进的结构和蛋白质组学方法定义与多种物种生物膜形成相关的细菌信号传导的保守和新机制。在分子水平上，这将包括确定血红素一氧化氮/氧结合蛋白（H-NOX）感知氧化剂和/或一氧化氮（NO）的机制，从而导致生物膜的形成或溶解。将利用x射线晶体学和核磁共振（NMR）以及x射线吸收精细结构（EXAFS）来确定结构。先进的蛋白质组学和磷酸化蛋白质组学将利用H-NOX缺失突变体在生物体水平上详细描述参与这一过程的信号网络。这种方法的结合将产生一个重要的信号传导过程的详细机制理解，以及它是如何进化以满足不同细菌物种的需要的。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Biofilms are stationary communities of bacteria that adhere to various surfaces. Inhabitation of a biofilm often makes bacteria resistant to clearance strategies that are effective against their free-living (planktonic) counterparts. As such, understanding the molecular cues that promote switching between the stationary and untethered lifestyles can guide our responses to biofilm formation in both beneficial and detrimental contexts. This project seeks to characterize cellular changes accompanying biofilm formation at the systems level, as well as the role of a particular family of sensor proteins in biofilm formation/dissolution at the molecular level. Student training is a major emphasis of this work. Students will be co-mentored by a team of scientists with expertise in diverse techniques and will have the opportunity to conduct transformative research at national laboratories. A proteomics workshop for graduate students will also be developed to train the next generation of scientists in this cutting-edge technology. The scientific objective is to define conserved and novel mechanisms of bacterial signaling relevant to biofilm formation across multiple species using advanced structural and proteomics methods. At the molecular level, this will include determining the mechanisms by which the heme nitric oxide/oxygen binding proteins (H-NOX) sense oxidants and/or nitric oxide (NO), resulting in biofilm formation or dissolution. Structure determination using X-ray crystallography and nuclear magnetic resonance (NMR) will be utilized as well as X-ray absorption fine-structure (EXAFS). Advanced proteomics and phosphoproteomics will detail the signaling networks involved in this process at the organismal level using H-NOX deletion mutants. This combination of approaches will yield detailed mechanistic understanding of an important signaling process and how it has evolved to meet the needs of diverse bacterial species.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.