CAREER: Role of Surface Properties in Motility of Bacteria to Control Biofilms

ID: MPS/DMR/BMAT(7623) 1151133 PI: Conrad， Jacinta ORG: University of houston标题：职业：表面特性在细菌运动控制生物膜中的作用知识价值：这个项目的目标是量化表面特性如何影响细菌的运动，具有高空间和时间分辨率。运动性是形成表面相关细菌生物膜的关键因素。生物膜一旦形成，就很难去除，这给石油和水管道、生物医学植入物和食品造成了数十亿美元的损失。降低这些成本需要新的策略来防止细菌形成生物膜。在生物膜形成的初始阶段，细菌改变它们的运动机制，使其能够不可逆地附着在附近的表面。为了验证细菌与表面之间的相互作用影响细菌附着和分离的运动特性和速率的假设，具体目的是：(1)通过测量表面运动的速度和持久性来阐明表面化学和弹性对扩散的影响。单细菌跟踪算法将用于跟踪在表面上移动的数千个细菌，这些细菌的表面电荷和弹性模量是通过逐层沉积来控制的，从而产生优化的表面特性，以最大限度地减少扩散。(2)量化对地表模式响应的定向持久性。细菌在特征尺寸为1-100微米的梯度表面上的均方位移、平均速度、持续时间和运动角度将使用趋化性模型进行分析，从而获得表面模式如何指导细菌运动的基本数据。(3)开发通过测量单个细菌的附着和脱离率来评估防污表面的检测方法。这些速率将与两种具有防污功效的表面上所产生的生物膜的结构相关，两亲性聚合物膜和分层皱褶表面。通过对表面特性对运动性、粘附性和生物膜形成的影响产生新的基本理解，该项目旨在实现合理设计抑制细菌定植从而阻碍生物膜形成的涂层。更广泛的影响：优化的防污涂层将有助于减少每年数十亿美元的水和资源管道的生物腐蚀损害，以及与医院获得性感染相关的成本。更广泛地说，对近表面运动的详细微观研究将对细菌与它们运动的表面之间的相互作用产生新的见解，从而对感染和病理以及防污表面特性进行定性的新研究。这项工作产生的信息丰富的数据将改进现有的定向运动和细菌粘附模型。最后，这些技术可以应用于将细菌附着和污染与广泛物种和表面的表面特性联系起来。拟议的研究将与教育和外联努力相结合，旨在增加服务不足的人口参与休斯顿的工程。首先，将与当地两所少数族裔高中（KIPP-Houston和DeBakey）合作，利用PI与NSF-RET和UH GRADE营地项目正在进行的工作，向大学前女性介绍工程学，开展生物污垢的培训和学习活动，激励学生学习工程学。第二，PI将继续通过UH和NSF-REU指导本科生进行研究。最后，两名研究生将在防污表面的研究方面受到指导，并将由PI发起跨学科的生物工程研讨会。拟议的教学和推广工作将扩大休斯顿多样化人口对工程的参与，反映在kipp -休斯顿和德贝基的非裔美国人和拉丁裔学生的高比例（分别为95%和56%）和低收入学生（80%和49%）。同样，PI将在休斯顿大学（13%的非裔美国人和21%的拉丁裔美国人）开展这些活动，休斯顿大学是美国第二多元化的研究型大学。这项研究的结果将由PI和她的学生在科学文献和石油和生物医学行业广泛传播，利用PI作为工业资助的博士后研究员的经验和她在德克萨斯医学中心的持续合作。

ID: MPS/DMR/BMAT(7623) 1151133 PI: Conrad, Jacinta ORG: University of HoustonTitle: CAREER: Role of Surface Properties in Motility of Bacteria to Control BiofilmsINTELLECTUAL MERIT: The objective of this project is to quantify how surface properties influence the motility of bacteria, with high spatial and temporal resolution. Motility is a critical factor in the formation of surface-associated bacterial biofilms. Once biofilms form, they are notoriously difficult to remove, resulting in billions of dollars of damage to oil and water pipelines, biomedical implants, and food. Reducing these costs requires new strategies to prevent bacteria from forming biofilms. In the initial stage of biofilm formation, bacteria modify their motility mechanisms to enable irreversible attachment to nearby surfaces. To test the hypothesis that motility characteristics and rates of bacterial attachment and detachment are affected by the interactions between bacteria and surfaces, the specific aims are: (1) To elucidate the effects of surface chemistry and elasticity on dispersal by measuring velocity and persistence of motion on surfaces. Single-bacterium tracking algorithms will be used to track thousands of bacteria moving on surfaces with controlled surface charge and elastic modulus engineered using layer-by-layer deposition, yielding optimized surface properties to minimize dispersal. (2) To quantify directional persistence in response to surface patterns. The mean-square displacement, mean speed, persistence time, and angle of motion of bacteria on gradient surfaces with feature sizes of 1-100 microns will be analyzed using models for chemotaxis, yielding fundamental data on how surface patterns direct motion in bacteria. (3) To develop assays to evaluate antifouling surfaces by measuring attachment and detachment rates of individual bacteria. These rates will be correlated to the structure of the resultant biofilms on two types of surfaces with demonstrated antifouling efficacy, amphiphilic polymer films and hierarchically wrinkled surfaces. By generating new fundamental understanding of the effects of surface properties on motility, adhesion, and biofilm formation, this project aims to enable the rational design of coatings that inhibit colonization by bacteria and thereby impede biofilm formation.BROADER IMPACTS: Optimized antifouling coatings will help to reduce the billions of dollars in biocorrosion damage in water and resource pipelines each year and in costs related to hospital-acquired infections. More broadly, detailed microscopic investigations of near-surface motility will yield new insights on the interactions between bacteria and the surfaces on which they move, enabling qualitatively new studies of infection and pathology as well as antifouling surface properties. The information-rich data generated by this work will improve existing models for directed motility and for bacterial adhesion. Finally, these techniques can be applied to correlate bacterial attachment and fouling to surface properties across a wide range of species and surfaces. The proposed research will be integrated with educational and outreach efforts aimed at increasing the participation of underserved populations in engineering in Houston. First, training and learning activities on biofouling that inspire students to study engineering will be developed in collaboration with two minority-serving local high schools (KIPP-Houston and DeBakey), leveraging the PI's ongoing work with NSF-RET and the UH GRADE Camp program for introducing precollege women to engineering. Second, the PI will continue to mentor undergraduate students in research through UH and NSF-REU. Finally, two graduate students will be mentored in research on antifouling surfaces, and interdisciplinary workshops on engineering for biology will be initiated by the PI. The proposed teaching and outreach efforts will broaden participation in engineering throughout the diverse population of Houston, reflected by the high proportions of African American and Latino (95% and 56%) and low income (80% and 49%) students at KIPP-Houston and DeBakey, respectively. Likewise, the PI will pursue these activities at the University of Houston (13% African American and 21% Latino), the second most diverse research university in the US. The results from this study will be widely disseminated by the PI and her students in both the scientific literature and to the petroleum and biomedical industries, leveraging the PI's experience as an industrially sponsored postdoctoral researcher and her ongoing collaborations at the Texas Medical Center.