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的固定细菌群落。生物膜的栖息往往使细菌对清除策略产生抵抗力，这些策略对自由生活(浮游)的细菌有效。因此，理解促进静止和自由生活方式之间切换的分子线索可以指导我们在有利和不利的环境中对生物膜形成的反应。该项目试图在系统水平上表征伴随生物膜形成的细胞变化，以及在分子水平上特定的传感器蛋白家族在生物膜形成/溶解中的作用。学生培养是这项工作的一大重点。学生将由一个在不同技术方面拥有专业知识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。还将为研究生开发一个蛋白质组学研讨会，以培训这一尖端技术的下一代科学家。科学目标是利用先进的结构和蛋白质组学方法确定与跨多个物种的生物膜形成相关的细菌信号的保守和新的机制。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)导致生物膜形成或溶解的机制。将利用X射线结晶学和核磁共振(核磁共振)以及X射线吸收精细结构(EXAFS)来确定结构。高级蛋白质组学和磷酸蛋白质组学将使用H-NOX缺失突变体在生物水平上详细说明参与这一过程的信号网络。这种方法的结合将产生对重要信号过程的详细机械理解，以及它是如何进化来满足不同细菌物种的需求的。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.