Discovering the regulatory mechanisms involved in bacterial cellulose biosynthesis

发现细菌纤维素生物合成中涉及的调控机制

• 批准号: RGPIN-2018-05975
• 负责人: Strap, Janice
• 金额: $ 2.62万
• 依托单位: University of Ontario Institute of Technology
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=713975
• 关键词: Discovering; regulatory; mechanisms; involved; bacterial

Extracellular cellulose, an unbranched polymer of --1,4-linked glucopyranose residues, is a crucial component of the biofilm structure of many plant and human pathogens facilitating their attachment to surfaces and providing protection against environmental stressors. Despite the obvious importance of cellulose as a microbial survival strategy, the mechanisms by which environmental signals regulate the synthesis of this important biopolymer are unknown. Acetic acid bacteria (AAB) are ubiquitous in acidic, sugary and alcohol-rich environments. These gram-negative bacteria are important for many biotechnological applications including the synthesis of bacterial cellulose (BC). BC synthesized by AAB consists of an ultrafine network of nanofibres that contribute to its highly crystalline structure and tensile strength making it important for many industrial applications such as paper, pharmaceuticals, wound dressings and tissue scaffolds. AAB can be isolated from fruits and flowers, however, the role cellulose plays in this plant-microbe interaction is not known. The long-range goal of this research program is to elucidate the multiple levels of regulatory control that affect not only the synthesis but also the physicochemical properties of cellulose. This knowledge is key to understanding the role bacterial cellulose plays in microbe-plant interactions and how the cellulose properties affect bacterial survival in the environment. The knowledge gained from this research program will be fundamental in engineering cellulosic materials with unique properties for diverse industrial applications and will be an important step towards finding regulatory targets for the control of cellulosic biofilms. To build on our recent work in this area and to further elucidate the regulatory circuits that control cellulose-mediated plant-microbe interactions, the specific objectives for this granting period will be to 1) characterize the functional role of FixK, a Crp/Fnr transcriptional regulator, in BC biosynthesis; 2) characterize the role phytohomones play in BC regulation; and 3) identify key phytohormone-responsive regulators of BC biosynthesis. This research program will provide interdisciplinary training to highly qualified personnel in the areas of microbiology, molecular biology, genetics, proteomics, transcriptomics, bioinformatics, biochemistry and material science.

细胞外纤维素是β-1，4-连接的吡喃葡萄糖残基的无支链聚合物，是许多植物和人类病原体生物膜结构的重要组成部分，有助于它们附着于表面并提供对环境应激源的保护。尽管纤维素作为微生物生存策略的明显重要性，但环境信号调节这种重要生物聚合物合成的机制尚不清楚。醋酸菌（AAB）普遍存在于酸性、含糖和富含酒精的环境中。这些革兰氏阴性细菌对于许多生物技术应用是重要的，包括细菌纤维素（BC）的合成。由AAB合成的BC由纳米纤维的超细网络组成，有助于其高度结晶结构和拉伸强度，使其在许多工业应用中非常重要，如纸张，药品，伤口敷料和组织支架。AAB可以从水果和花中分离出来，然而，纤维素在这种植物-微生物相互作用中的作用尚不清楚。该研究计划的长期目标是阐明不仅影响纤维素合成而且影响纤维素物理化学性质的多层次调控。这些知识是理解细菌纤维素在微生物-植物相互作用中的作用以及纤维素特性如何影响细菌在环境中生存的关键。从这项研究计划中获得的知识将是工程纤维素材料的基础，具有独特的性能，可用于各种工业应用，并将是寻找控制纤维素生物膜的监管目标的重要一步。为了进一步阐明纤维素介导的植物-微生物相互作用的调控机制，本研究计划的具体目标是：1）确定一种Crp/Fnr转录调节因子FixK在BC生物合成中的功能作用; 2）确定植物激素在BC调控中的作用;和3）鉴定BC生物合成的关键植物激素响应调节剂。该研究计划将为微生物学，分子生物学，遗传学，蛋白质组学，转录组学，生物信息学，生物化学和材料科学领域的高素质人才提供跨学科培训。